Research Article
S. I. Shariati; M. H. Aghkhani; M. R. Golzarian; A. A. Akbari
Abstract
IntroductionRobots used for material handling several ages and their usage promote with intelligent technologies. Many researchers proposed different robots in this field but it is very important to design customized configurations for farms. Researched experiences are limited to some agricultural mobile ...
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IntroductionRobots used for material handling several ages and their usage promote with intelligent technologies. Many researchers proposed different robots in this field but it is very important to design customized configurations for farms. Researched experiences are limited to some agricultural mobile robots in our country. Main topic in this paper is designing and modeling of workspace and kinematics analysis of manipulator in agricultural farm. Materials and Methods This article investigates workspace and kinematics of robot manipulator in order to design and manufacturing a 4 DOF Manipulator for farming. This manipulator will be capable of doing a variety of different tasks, but what this project is looking for is loading and unloading of materials and products on the farm as an auxiliary force for the farmer.In order to design and analyze a manipulator, the first step must be to determine the type of task that the arm is going to perform. For example, a trailer containing forage packages should be unloaded or loaded at a suitable location. An intelligent robotic arm that attached to a tractor can perform this operation in the shortest possible time without the intervention of the workforce. This stage requires a large amount of labor. In fact, workers need to move boxes of 10kg at a distance of 3 to 4 meters at a height of 1 to 2 meters and this will require a great deal of torque.Design of arm kinematics model, direct kinematic equations, velocity kinematics, and Jacobian matrix solving were performed at this stage. The calculations were performed by two methods manually and using kinematic modeling in MATLAB software for three arm configurations in two simulation tests and the results were compared. Workspace analysis of the selected manipulator configurations and use of arm kinematic performance evaluation indices are illustrated in graphs. Results and Discussion The issue of moving forage packages on the farm is described below. If the farmer is to move 48 packages of fodder weighing about 10 kg manually (human worker) in the work space modeled in Figure 10, the time to move each pack in the reciprocating mode on the unobstructed path will be 30 seconds on average. Packages will be available in 24 minutes. However, the result of the linear speed of the final operator of the robot arm in the first test is 1 meter per second, which is 3.7 times the working state, and the total movement of the packages will be done in about 6.5 minutes.Examining the final performer's velocity diagram in both tests shows that we will not have much difference due to the change of configurations on the speed and acceleration of the final performer's arm. Comparison of robot workspace evaluation indicators was normalized with two methods of workspace index and structural length index was calculated for all three configurations and the results showed that the configuration of type 1 was appropriate. The manipulability index of the robot arm, according to the diagrams obtained for all three configurations in the two tests, shows that the first type has a better score than the other two types, and as a result, the final performer will be able to perform better. This configuration is one of the best situations, as Yoshigawa suggested for the first three joints of the Puma robot. Conclusions One of the main points in using robots in agriculture is the appropriate kinematic design of joints and links for work operations. Using this example of robots in the operation of moving products on the ground as a help to the user (driver) will take less than a quarter of time, and in terms of energy consumption and cost in a certain period has economic justification. Based on the studies conducted, type 1 configuration has passed the kinematic path in both tests with a higher manipulability index, and its workspace index is more appropriate based on both calculated criteria.
Research Article
Precision Farming
B. Besharati; A. Jafari; H. Mousazadeh; H. Navid
Abstract
IntroductionVarious methods have been performed to control weeds in the world which the use of herbicides is one of them, but public concerns about human health have changed interests in alternative methods. Thermal methods based on flame-weeder, hot air, steam, and hot water have the potential to control ...
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IntroductionVarious methods have been performed to control weeds in the world which the use of herbicides is one of them, but public concerns about human health have changed interests in alternative methods. Thermal methods based on flame-weeder, hot air, steam, and hot water have the potential to control weeds, but due to the high cost are not economical. Electromagnetic waves transfer energy into weeds and finally destroy them. The effect of radiation on plant mutation, high consumption of energy and human health are problems for this approach. Unlike other methods, electrical energy is an ideal and non-chemical method to weeds. This method applies high voltage to weeds, their roots, and soil so that electric currents pass through them, and the vaporization of the liquid weeds contain kills the weeds. To increase the severity of damage on weeds, the development of a feedback mechanism is required. The ultrasonic sensor measuring physical parameters like plant height is a simple method. Some complex sensing systems include optical sensors such as infrared, machine vision that require high-speed processors and expensive equipment. In this project, as a simple method, the monitoring of the electrical current passing through weeds was used for developing the feedback mechanism and increasing electric damage on weeds. Materials and MethodsIn this study, the system consists of a high voltage device to make a 15 kV AC voltage to kill weeds and a feedback mechanism included a sensor to measure the electric current on the input of the weed killer and identify the existence of a weed and its annihilation. All parts installed on a robotic platform and an application on a laptop was connected to it via an access point for navigation and receiving data. The system was tested in a greenhouse lab with some weeds. At first, to investigate the effect of high voltage on the weeds and find the relationships between the electric currents passing through weeds and the presence of them (before and after the annihilation), a test was performed so that the system was guided on a path and applied high voltage to kill the weeds. Finally, the feedback mechanism was calibrated after relations for the electric current data were extracted. By calibrating the feedback mechanism, the system was able to identify weeds and the annihilation of them so that after the annihilation of a weed, the system was allowed to move to kill another weed. After the calibration test, to compare the weed killer efficiency of the two methods of use and non-use of the feedback mechanism, a test was performed, and the results were analyzed by using the t-test at p ≤ 0.01.Results and DiscussionThe observations indicated that input electric current on the weed killer depended on the electric current passing through weeds. When the high-voltage electrode touched a weed, the electric current passed through weeds increased, and simultaneously the high electrical energy destroyed weeds. After destruction and removal of them, the electric current rapidly decreased. The average energy consumption per weed plant was estimated at 250 joules can be compared with other methods. The final test to compare the use and non-use of the feedback mechanism revealed that there are significant results (P < 0.01) for using this mechanism and as a result, increases the efficiency of weed annihilation. The sensing system of the developed feedback mechanism is a simple method affected by the electrical resistivity of weeds so that, unlike an ultrasonic mechanism did not cause another object to be detected as a weed. According to this result, the monitoring of the electrical current passing through weeds was suitable for developing a feedback mechanism for the weed killer to identify the existence of a weed and its annihilation.ConclusionsHigh voltage should be used as a non-chemical and alternative way to kill weeds. The results indicated that the measurement of the electric current on the input of the weed killer was an appropriate and simple method for the development of a feedback mechanism to identify the existence and annihilation of weeds that also increased the electric damage on weeds. It is suggested that for future research, the weed killer attach with an automatic guidance mechanism to increase capacity and forward speed.
Research Article
Design and Construction
S. Naderi Parizi; R. Alimardani; M. Soleimani; H. Mousazadeh
Abstract
IntroductionActivated carbon has a wide range of applications as a porous material in liquid phase or gas phase adsorption processes. The physical process of activated carbon production is divided into two stages of thermal decomposition and activation. In this study, only activation stage has been studied, ...
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IntroductionActivated carbon has a wide range of applications as a porous material in liquid phase or gas phase adsorption processes. The physical process of activated carbon production is divided into two stages of thermal decomposition and activation. In this study, only activation stage has been studied, because it is very important in the properties of the activated carbon being produced.The production of activated carbon from horticultural waste not only leads to cheap production and supply of many industrial and environmental necessities, but also reduces amount of the produced solid waste. Iran produces about 94,000 tons of pistachio husk annually, which is a good raw material for the production of activated carbon. The profitability index of activated carbon production in Iran is equal to 3.63, which in case of export, this index will be tripled.Researches were depicted that the three factors of temperature, period and activation gas flow had the greatest impact on burn off and iodine number. Also steam was introduced as the fastest and the most valuable effective activator. The minimum iodine number required for economic efficiency of activated carbon is 600 mg g-1 while the highest specific surface area is 1062.2 m2 gr-1 for pistachio crop according to the BET test.Materials and MethodsA 10 mm thick steel Mannesmann tube was used to build the rotating reactor. In order to reduce heat loss, the kiln body was surrounded by a ceramic blanket with a temperature tolerance of about 1400 °C. The kiln length and diameter were 190 cm and 48 cm and the actual operating temperature was considered to be 600 °C. To achieve this temperature, about 25 kWh of energy is consumed in the heating unit. The CATIA V5 R21 software was used to design the device and the ANSYS R20 software was used for thermal and mechanical analysis. The most important component was the rotary reactor because a lot of thermal and mechanical stresses occur in this part. To provide a solution to control these stresses, it was necessary to determine the stresses and change the lengths due to heat. For this purpose, the thermal and fluid analysis of the kiln was performed and then the results of the analysis were coupled with a mechanical analysis. After that, the experimental test was performed on the real model and the results were compared together with statistical analysis. T-student test was used in IBM SPSS software.Initially, central heating unit and its circumstance was modeled with ANSYS CFX. Fluid velocity, radiant properties and heat transfer of the kiln and the range around that were obtained at assumed temperature (650 °C) of the heating unit. In the space between the kiln and the heating unit, velocity of steam flow was uniform. In order to provide longitudinal movement of the device due to heat stress and define the degree of freedom in the longitudinal direction of the device, a pair of taller rollers was used and lateral movement was not restrained on that roller. This allows the reactor length to increase at different temperatures. On the other hand, the end of the reactor is designed by grooves and pressure plates in such a way that while properly sealing the device using abrasion and compression plates designed with refractory fibers, the parts move telescopically inside each other and neutralize the effects of expansion.Results and DiscussionOperating temperature was increased in the system, gradually in order to reduce the thermal stresses in the reactor shell. The maximum increment in longitudinal increase in the kiln was obtains as 11.75 mm. The results of 5 experimental tests and 5 software analyzes showed that there was no significant difference between the experimental and analytical results at the level of 5%. Using the results of thermal contour analysis, the thickness of the insulation layer was calculated equaled 5 cm. To control the operating temperature of the device, two methods contained changing the flame length of the burner and different exhaust outlets were applied, which enabled to reduce thermal stress.ConclusionThermal and mechanical analysis were the efficient methods for calculating heat distribution and thermal stresses as well as dimensional changes in the activated carbon reactor. Using the mechanism of abrasive plates and friction washers, changes in the length and diameter of the reactor was compensated. By controlling the inlet exothermic of the burner and controlling the flow of exhaust gases, thermal stresses were decreased.
Research Article
Agricultural systems engineering (greenhouse, fish farming, mushroom production)
S. Noroozi; A. Maleki; Sh. Besharati
Abstract
Introduction Solar energy is one of the most important sources of renewable energy and it use to resolving the problems of energy needs include, increase fossil fuels, increase energy conduits prices, higher energy demand worldwide and greenhouse gas emissions. Solar collectors using, the sun's thermal ...
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Introduction Solar energy is one of the most important sources of renewable energy and it use to resolving the problems of energy needs include, increase fossil fuels, increase energy conduits prices, higher energy demand worldwide and greenhouse gas emissions. Solar collectors using, the sun's thermal energy and it converts into useful and usable energy. Solar collectors are divided into parabolic types (PTC), linear Fresnel reflectors (LFR), solar plates and central towers. Among them, the most common heat generation systems are linear adsorption technologies. We examine the LFR system for greenhouse heating in shahrekords winter.Materials and Methods Studies (Huang et al., 2014) can be used for optical analysis, Daneshyar model can be used to calculate the amount of light energy of the sun For a specific location, The mathematical formula is used to calculate the instantaneous energy equilibria. A heat transfer resistance model is presented and the heat loss of different parts of the collector can be calculated. For modeling, the total amount of exergy must first be obtained, which can be used using the petlla formula given in (Bellos et al., 2019).Results and Discussion The studies performed include the following results: -The proposed mathematical modeling for calculating solar energy is accurate in terms of daily and instantaneous performance. This model is valid for both clear and cloudy days, so it can be applied in a variety of weather conditions.- The maximum useful heat production of the current system for the February is about 2.5 kW, while the increased liquid temperature in the heat tank is 16 degrees Celsius.- The maximum thermal efficiency of Fresnel collector during the day is 65%. The average daily efficiency is 56.4%.-The most important parameters that affect the production of useful energy are the position of the sun during the day and the amount of cloudy day.- The system has the ability to heat the stored water in the source up to a temperature of 98 degrees per day. This amount is available up to 14 hours.-The system under consideration can be used for heating up to 1260 watts without heating the tank for 15 hours. , heat generation can be use as, food industry steam production and industrial desalination water.-The decrease in exergy efficiency is due to the decrease in the thermal efficiency of the system as well as the increase in the thermal difference between the collector and ambient temperatures. Higher values can be achieved by reducing the heat losses. Which is itself a reason to reduce the exergy efficiency of the system.Conclusions In this paper, daily performance of a linear Fresnel collector with 18 square meter mirror field, a parabolic collector and an insulated storage tank with a volume of 250 liters is investigated, which includes experimental analysis, theoretical formulation of thermal phenomena and The weather conditions in Shahrekord have been. The mathematical model developed is based on the energy balance in the collector and storage tank. Has an efficient greenhouse heating system and average thermal efficiency of 56%. Which is a reasonable amount and competitive with other similar technologies, the cost of construction and maintenance is much lower than competitors.
Research Article
Post-harvest technologies
Z. ZanganehVandi; H. Javadikia; N. AghiliNategh; L. Naderloo
Abstract
Detection of different percentages of palm in corn oil with the help of an electric noseIntroduction The reason for using corn oil in the diet is its positive effects on the cardiovascular system and the immune system. Corn oil contains 99% triacylglycerol. It itself contains 59% unsaturated fatty acid, ...
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Detection of different percentages of palm in corn oil with the help of an electric noseIntroduction The reason for using corn oil in the diet is its positive effects on the cardiovascular system and the immune system. Corn oil contains 99% triacylglycerol. It itself contains 59% unsaturated fatty acid, 24% unsaturated fatty acid contains a double bond and also contains 13% saturated fatty acid. For this reason, corn oil has a high amount of unsaturated fatty acids and can be a good alternative to saturated fatty acids. Because it reduces blood cholesterol and therefore is more important than other oils consumed. In this study, an electrical nasal system was used to detect the amount of palm in corn oil. The properties extracted from the signals obtained from the device were processed by principal component analysis, artificial neural network, infusion and response surface and the results were compared with each other to find the best method to detect the palm level in Specify the oil.Materials and Methods the required palm oil was obtained from Nazgol Oil Agro-industrial Plant and corn oil was obtained from natural lubrication centers. To prepare samples with different percentages of palm, for each sample, 75 grams of palm oil and corn oil with the specified percentages were prepared and stored in special containers. Ten metal oxide semiconductor sensors (MOS) were used in the electrical nose system. Output data of sensors on which pre-processing operations were performed by RSM, ANFIS, PCA, ANN methods to estimate the percentage of palm in corn oil, using Unscrambler V. 9. Software, Design expert 8.07 1. And MATLAB R2013a were analyzed. Results and Discussion According to the Score diagram, the principal components of PC-1 and PC-2 were 53% and 25%, respectively, which describes the amount of variance between the samples for a total of 78 total data. According to the obtained results, it can be seen that sensors 7 and 8 had little effect on the detection process and can be removed from the sensor array. When the cost of making the sensor array of the olfactory system needs to be reduced, sensor 6 has a greater role than other sensors in detecting corn oil with palm composition. According to the loading diagram of palm percentage in corn oil, MQ6 sensor had the least effect in classifying different percentages of palm in corn oil and pattern identification. According to the methods analyzed in this study, the ANFIS method is a more appropriate method for determining the percentage of palm in corn oil and also according to the amount of all functional parameters (accuracy, sensitivity and specificity) Regarding the separation of corn oil and palm oil by ANFIS, RSM and ANN, according to Table 3-1, we came to the conclusion that it is better to use RSM method in classifying corn and palm oil.Conclusions In this study, to analyze the different aromatic compounds of different oil and palm samples, to detect the palm, an electronic nasal multi-sensor system based on metal oxide sensors was used. The created system provided comparable information for classifying different samples of different palm oils. Using PCA, ANN, ANFIS and RSM methods, we discussed the system performance to differentiate and classify different oil and palm samples. 1. The results obtained from loading diagrams for the detection of corn oil palm showed that in corn oil, the MQ6 sensor had the least effect on the detection process. The sensor that has the least role for corn oil can be removed from the sensor array. 2. It is better to use RSM method to detect different percentages of palm in corn oil. Keywords: Fatty acid, fraud, Sensory evaluation
Research Article
Image Processing
Sh. Falahat; A. Karami
Abstract
Recently deep learning-based approaches have gained particular attention in precision agriculture to detect and count pests or plant diseases, intelligent spraying, estimating the area under cultivation, and monitoring the growth stages of the plants to deal with growth reducing factors or obstacles ...
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Recently deep learning-based approaches have gained particular attention in precision agriculture to detect and count pests or plant diseases, intelligent spraying, estimating the area under cultivation, and monitoring the growth stages of the plants to deal with growth reducing factors or obstacles and to increase the productivity of agricultural products. In this article, high-resolution RGB images acquired by unmanned aerial vehicles (UAVs) of two different growing season dates from large-scale maize fields are used. A fast and accurate single-stage object detection technique based on deep convolutional neural networks, YOLOv5s, is modified to improve its performance for maize tassel counting and is called MYOLOv5s. Main modifications are applied to the architecture and activation functions of the original YOLOv5s detector to increase the number of suitable features, decrease overfitting, and improve tassel detection accuracy. The proposed technique can detect and count the maize tassels with an average accuracy (AP) of 95.30% and a coefficient of determination (R2) of 99.28%. The performance of MYOLOv5s is compared with three state-of-the-art algorithms Tasselnetv2+, Faster R-CNN, and RetinaNet. The obtained R2 values for these algorithms are 77.86%, 86.83%, and 95.53%, respectively. In addition, Faster R-CNN and RetinaNet algorithms achieved 76.99% and 77.66% AP values, respectively. These results show the high efficiency of the proposed method in detecting maize tassels. It is worth mentioning that MYOLOv5s with an inference speed of 84 frames per second is the fastest technique in detecting maize tassels.
Research Article
Image Processing
M. Fallah; E. Ghanbari Parmehr
Abstract
The population increase in the world highlights the need for agricultural products more than before. Rice is one of the most important food sources in the Middle East countries. In addition, rice is a strategic product and has been one of the most important imported products in the last two decades. ...
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The population increase in the world highlights the need for agricultural products more than before. Rice is one of the most important food sources in the Middle East countries. In addition, rice is a strategic product and has been one of the most important imported products in the last two decades. Effective coping with pest on rice fields is one of the most important challenges in agriculture. Crambus suppressalis is a key pest of rice in north of Iran. The damage of this pest can reduce production such as buds and if it occurs at the end of the culture period, plants have white head. The raise of farmers' knowledge about the pest type and proper method of pest control can increase the productivity. Currently, the identification of rice pest type relies on the framers experience which is not error free method. To minimize the losses of crops, diagnosis is required in early stages for preventive action. The development of artificial intelligence and machine learning algorithms created a new horizon for all industry fields including agriculture. The use of machine learning can prevent many errors in the pest identification. On the other hand, in recent years , the use of smart phones and the emerge of third and fourth generation of mobile phone networks and the development of voluntary information have enabled automatic monitoring of farms to reduce human resources and errors. The first goal of this research is feasibility study of training model based on smart phone images for detection of pest type using deep neural network technique. In this paper, the convolutional neural network and the increasing artificial data technique with the aim of preventing more fitting and creating all imaging modes with potential noise have been used. The results show that the training model has provided a good performance in the diagnosis of the pest by using smart phone images with precision and kappa value. The second goal is to design and develop a mobile application for the farmer in order to control the pest timely and accurately. This application will be able to solve the pest type identification problem using volunteered geographic data and machine learning technique.
Research Article
Agricultural systems engineering (greenhouse, fish farming, mushroom production)
P. Shamsi Roodbarsar; S. R. Mousavi Seyedi; D. Kalantari; K. Ghasemi
Abstract
introductionIt is predicted that the world population will grow to 9.3 billion up to 2050 and urban population will grow 73% It means that it will grow from 3.6 billion to 6.3 billion. This huge population need huge amount of food production. Plant factory with artificial light (PEAL) is called to a ...
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introductionIt is predicted that the world population will grow to 9.3 billion up to 2050 and urban population will grow 73% It means that it will grow from 3.6 billion to 6.3 billion. This huge population need huge amount of food production. Plant factory with artificial light (PEAL) is called to a factory with stock structure which is isolator to heat and is Impenetrable of air. The plant grow in shelves under electrical light which are laid horizontal and the goal is to produce and sell the plants, but min PFALS has not Commercial goals and are producing agricultural products in domestic and small sizes.Usually calories resource for human and animal or plants that need large farm to grow are not suitable for the plant factory. The main purpose in the research is to study the proper light quality for growing plants. The effect of mixed lights (red, green, blue) are studied for quantity of photosynthesis and growing plants. The result showed that the effect of red and blue light are very good in growing radish.The stem length in blue and red light was increased and in mixed light was decreased also the red and fluorescent light grow bigger radishes.Materials and methodsRadish is studied in this investigation. The place of growth is built vertically in 4 floor. Each floor has been divided into two sections. There should be a controller in each section, to control the parameters like light time light off and light on, temperature moisture. In this method the controller is designed by the fritzing software and the parts and sensors of DHT 11, Arduino UNO, based on ATMEGA328P, Relay module Arduino, data logging shield, driver module RC are used.For writing down the codes to control the other needed parameters, the programming platform like Arduino is used in this study 7 different light cares are used plus sunlight as testifier.This light cares are developed throw changing the number of 3 lights (red, green, blue), after designing and controlling m-PFAL, LEDs are installed. According to previous studies which are done in this matter all LED lights are installed off the shelves, so that the plants can use the proper amount of light in vertical state and some lights are installed beside the plants so that the lower leaves can get the proper light. In this study LED light with 7 different spectrum and sunlight as a testifier are used. The plants vs accidentally in 8 cares and 3 repetitions and all the data analysis are done through SAS soft there the average comparison or done in duncan method and probability of 1% and 5%.Results and discussionAccording to results, light regime (R2,G0,B1) has the highest amount of chlorophyll “a”, that has meaningful difference with the witness and the other treatments. The lowest amount of chlorophyll “a” was related to (R1, G0, B0) treatment, that didn't have meaningful differences with (R1,G1,B1) witness. The highest amount of chlorophyll “b” was related to (R2,G0,B1) treatment, that had meaningful difference with the witness, but in comparison with (R2, G1, B0) and (R1, G0, B2) treatments didn't have meaningful differences. The mixed light treatment of blue and red, specially when the red light is more, the amount of photosynthesis is higher. The highest wet weight was seen in (R2, G0, B1) treatment, which didn’t have meaningful difference with natural light. The lowest wet weight was seen in just red light treatment, that was very low in comparison with the other treatments. According to results, dry weight of radish is 4-6 percent of its wet weight. In dry weight just like the wet weight, the highest amount was for (R2, G0, B1) treatment that didn’t have meaningful difference with (R0, G1, B2) and (R1, G0, B0). The highest amount of sugar was seen in (R2, G0, B1) treatment that was very high in comparison with other optical regimes and natural light. Because the production of carbohydrates and sugar has direct relation with Photosynthesis, so we can conclude that in (R2, G0, B1) treatment the state of photosynthesis is more proper. Conclusion in case of limitations of natural light in greenhouse and multi-floor planting and plant factories, LED lights in optimized quality can be a good alternative.Also it has been indicated that the best light mixture is red and blue light, when the red light is more than the blue light.And the worst light regime is the only red color which had negative effect on all parameters.
Research Article
Design and Construction
A. Mohammadi; K. Kheiralipour; B. Ghamari; A. Jahanbakhshi; R. Shahidi
Abstract
IntroductionOperator permissible exposure time to vibration is one of the key factors in maintaining the operator health on one hand and optimizing machinery and equipment in another hand. The tractor is manufactured in Iran. The purpose of the present study was to calculate the operator permissible ...
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IntroductionOperator permissible exposure time to vibration is one of the key factors in maintaining the operator health on one hand and optimizing machinery and equipment in another hand. The tractor is manufactured in Iran. The purpose of the present study was to calculate the operator permissible time to the vibration of the tractor so that the driver can use the tractor with maintaining body health.Materials and MethodsIn this study, the experiments were conducted using a 3-axis vibration meter based on ISO 2631 standard. The obtained data were analyzed using a factorial experiment based on the measurements with 18 treatments and 3 replications. The studied factors were engine rotation speed (at three levels of 1000, 1500, and 2000 rpm), road (dirt and asphalt), and gear position (at three levels of 1, 2, and 3).Results and DiscussionThe various total vibration models for the tractor were obtained and the determination coefficient of them varied from 90.11 % for gear No. 3 and asphalt road to 100 % for gear No. 1 and asphalt road and gear No. 2 and dirt road. The maximum whole-body vibration and consequently the minimum of permissible exposure have belonged to gear No. 3, engine rotation speed of 2000 rpm and dirt road as 1.49 and 1.16 h, respectively.ConclusionThe maximum of whole-body vibration of the tractor for 8 h driving was obtained as 0.85 m s-2. The permissible exposure time decreases with the increase of vibration until it reaches 1.16 h. Adhering to these permissible exposure times in various driving conditions by the drivers, some measures should be taken to reduce the vibration of the tractor as well as to reduce the transmission of vibration to the driver to reduce the whole-body vibration of the tractor and increase the driver permissible exposure time.
Research Article
The relationship between machine and soil
J. Taghinazhad; S. Rahmani
Abstract
IntroductionHarvesting stage is the most important stage of peanut production. In other words, one of the critical stages of production of this product is the harvest stage. This stage, while having its own difficulties, is associated with significant losses, which are considered by experts due to its ...
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IntroductionHarvesting stage is the most important stage of peanut production. In other words, one of the critical stages of production of this product is the harvest stage. This stage, while having its own difficulties, is associated with significant losses, which are considered by experts due to its high economic value. In recent years, this product has also been considered by farmers in the Moghan Plain due to the special conditions of the Iranian economy. In this study, three methods of peanut harvesting were investigated in two stages including manual, tractor-mounted thresher (semi-mechanized) and Harvesting with pull type combine in 2020. The first stage involves the complete removal of the plants from the soil and the second stage is the drying and separation of the peanut pod from the plant in Moghan. Methods and Materials: The experiment was performed based on a split plot design in the form of randomized complete blocks with four replications. Main plot includes soil moisture at harvest time in three levels: a1-21%, a2-18% and a3-15% and sub-plot includes separation of peanut pod from plant at three levels were: b1- combine harvesting b2 - harvesting with a tractor-mounted thresher, b3 - manual harvesting. Therefore, in this study, while evaluating important harvest indicators such as quantitative loss )first and second stage losses ( , actual field capacity, harvest time, number of labor required and final the best harvesting system was introducedResults and Discussion:The results showed that the most suitable soil moisture content for the first stage harvest was 18%. The difference between most parameters between treatments was significant at 1%. The maximum and minimum farm capacities for pull type combine and manual harvesting method were 0.46 and 0.006 ha ha-1, respectively. The lowest and highest total losses with 5.95 and 10.58%, respectively, were related to harvesting with manual and pull type combine method. Also, the manual harvesting method required more labors than other methods. Conclusion:According to the obtained results, it was determined for the early harvesting of peanuts a pull type combine and suitable quality of the obtained product peanut with manual method is recommended for Moghan region.
Research Article
Image Processing
S. Abdanan
Abstract
Introduction Transplanting technology has the characteristics of improving disaster resistance and stress resistance of crop growth, ensuring stable yield and improving product quality. Currently, the cultivation in seed trays relies on huge labour power and further mechanization is needed in order to ...
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Introduction Transplanting technology has the characteristics of improving disaster resistance and stress resistance of crop growth, ensuring stable yield and improving product quality. Currently, the cultivation in seed trays relies on huge labour power and further mechanization is needed in order to increase production. However, there are some problems in this operation, such as the difficulty of improving the speed of single machine, seedling deficiency detection, automatic planting, controlling the quality, which need to be solved urgently. To solve these problems, there are already some meaningful attempts. Si et al. (2012) applied photoelectric sensor to vegetable transplanter, which can measure the distance between seedlings and the movement speed of seedlings in seedling guide tube, in order to prevent omission transplantation. Yang et al. (2018) designed a seedling separation device with reciprocating movement of the seedling cup for rice transplanting. Tests show that the structure of the mechanical parts of seedling separation device meets the requirements of seed movement. The optimization of the control system can improve the positioning accuracy according to requirements and achieve the purpose of automatic seedling division. Chen et al. (2020) designed and tested of soft-pot-tray automatic embedding system for light-economical pot seedling nursery machine. The experimental results showed that the embedded-hard-tray automatic lowering mechanism was reliable and stable as the tray placement success rate was greater than 99%. The successful tray embedding rate was 100% and the seed exposure rate was less than 1% with a linear velocity of the conveyor belt of 0.92 m/s. The experiment findings agreed well with the analytical results.Despite the sharp decline in Iran's water resources and growing population, the need to produce food and agricultural products is greater than ever. In the past, most seeds were planted directly into the soil, and many water resources, especially groundwater, were used for direct seed sowing and plant germination. One way to reduce the consumption of water, fertilizers and pesticides is to plant seedlings instead of direct seed sowing. Therefore, the purpose of this study was dynamic modeling and fabrication of seed planting system in seedling tray. Material and MethodsIn this experiment, Flores sugar beet seeds (Maribo company, Denmark) were used. The seedling trays had dimensions of 29.5*60 cm with the openings and holes of 5.5 and 4 cm, respectively. In order to planting seeds in seedling trays, first a planter arm was modeled and its position was obtained at any time. Then, based on dynamic modeling, the arm was constructed and a capacitive proximity sensor (CR30-15AC, China) and IR infrared proximity sensor (E18-D80NK, China) were used to find the location of seedling trays on the input conveyer and position of discharging arm, respectively. To achieve a stable and effective control system, a micro-controller-based circuit was developed to signal planting system. The seed planting operation was performed in the seedling tray according to the coordinates which were provided through image processing method. The planting system was evaluated at two levels of forward speed (5 and 10 cm/s). Moreover, a smartphone program was implemented to monitor the operation of planting system. Results and Discussion The planting system was assessed for sugar beet seeds with two levels of forward speed (5 and 10 cm/s) and the nominal capacity of this planter was obtained between 3579 to 4613 cells per hour. In addition, miss and multiple implantation indices in 3000 cells were 0.03% and 8.17%, respectively. Due to the planting accuracy, speed of the planter and also low energy consumption (25.56 watts. hour), this system has the ability to replace manual seeding in the seedling tray.ConclusionIn the present study, a seed sowing system for planting the seedling tray was designed, constructed and evaluated based on dynamic modeling. In the developed system, contrary to previous research, planting location detection was conducted by image processing. Besides, a smartphone program was established to monitor the operation of planting system without interfering the performance of the plantation. This study demonstrates that the image processing could, successfully, detect planting location and could effectively utilize over time for the major producers.
Research Article
Design and Construction
P. Ghiasi; M. Salatin; R. Soon; S. M. Mir Esmaeili; K. Pirvandi; Gh. Najafi
Abstract
Introduction: The world today is facing the issue of population growth, which will result in food shortages. One of the ways to supply food to this growing population is to produce more agricultural products and facilitate its production to cover the increase in demand. One of the important products ...
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Introduction: The world today is facing the issue of population growth, which will result in food shortages. One of the ways to supply food to this growing population is to produce more agricultural products and facilitate its production to cover the increase in demand. One of the important products of the agricultural sector is medicinal plant. In Iran, medicinal plants are harvested manually. Manual harvesting reduces the agricultural productivity of these crops, and manpower constraints are another problem with this type of harvesting. Cost and time consumption of manual harvesting are other features of this type of harvesting. Given the importance of the development of medicinal plants, the design and construction of a mechanized machine for harvesting medicinal plants is essential.Material and methods: In designing the machine for harvesting medicinal plants in cultivation rows, different scenarios regarding the position of the machine relative to the tractor were examined. The advantages and disadvantages of each were listed separately and finally the placement of tractors, harvesters and trailers was defined continuously. One of the goals of designing a machine for harvesting medicinal plants is to perform harvesting operations for two row spacing of 80 and 160 cm. Therefore, the mechanisms to change the position of the harvesting head were added to the machine. In addition to the ability to change the transverse distance, the machine must also be able to change the cutting height. According to the sensitivity of the product to avoid contact with the soil, the plants should be transferred to the trailer immediately after cutting. The transfer mechanism was designed and built to move the cut products to the trailer. Independent variables including: forward speed in two levels, type of reel in two types and cutting blade in two types were considered. Dependent variables also included: harvesting efficiency, percentage of damaged plants and harvesting capacity.Result and Discussion: The results of variance analysis for different treatment showed that the effect of forward speed, type of reel and cutting blade type has an effect on harvest efficiency and the difference in harvest efficiency is significant at the level of 1% probability. A star cutting blade provides more efficiency than a 40-teeth blade cutting blade. The rubber reel prevents the plants from falling to the ground due to the closed space it creates in front of the blade. But the inner parts of the rods reel are empty and the plant can fall down on the ground. The plant is also wrapped around rods this cause to decrease the harvesting efficiency. Another important parameter in identifying and evaluating a harvesting machine is crop damage. Some plants are crushed and torn due to impact on metal components. This situation reduces the quality of the harvested product and causes the price of the final product to fall. The star-cutting blade causes more rupture to the leaves. The teeth in the 40-teeth blade are continuously, and the possibility of the leaf being between the two teeth is very low, but in the star blade, the distance between the two blades is large and the plant can be placed in between and re-cut.Conclusions: According to the tests performed for 8 different positions of the harvester, G test showed better performance than other tests. 85.88% for harvesting efficiency, 344.8 kg/h of capacity and 1.34% of mint leaf damage. Accordingly, for harvesting similar products of mint, a combination of star blade, rubber carousel and a forward speed of 1.2 meters per second is recommended. New tests should be performed on other products such as lavender and other products with strong stems.
Research Article
Agricultural systems engineering (greenhouse, fish farming, mushroom production)
M. Jalali; A. Banakar; B. Farzaneh; M. Montazeri
Abstract
IntroductionIn the poultry industry, reducing energy consumption is in line with reducing costs. The energy required in the poultry industry includes heating, cooling, lighting and power line energy. Identifying the factors that increase energy is essential and providing appropriate solutions to reduce ...
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IntroductionIn the poultry industry, reducing energy consumption is in line with reducing costs. The energy required in the poultry industry includes heating, cooling, lighting and power line energy. Identifying the factors that increase energy is essential and providing appropriate solutions to reduce costs and energy is inevitable. One of the most important and costly factors in the poultry industry is the use of fossil fuels and the pollution caused by them. Energy costs have a direct impact on the cost of production and increase the per capita cost of production in the meat and egg sectors. In Iran, poultry farms, as one of the subsets of the agricultural sector, are among the most widely used energy sectors, the main part of which is related to the heating of breeding halls.Materials and MethodsThe studied problem is thermal simulation of a meat poultry farm in Ardestan city of Isfahan province. Ardestan city is located in the north of Isfahan province in a desert region with north latitude of 33 degrees and 23 minutes and 52 degrees and 22 minutes east longitude. The dimensions of the poultry hall floor are 5 meters by 8 meters and with a poultry capacity of 300 pieces. Inlet air vents (windows) are 2 with dimensions of 1.90 by 1.6 meters. The average height of the roof is 2.5 meters and the roof is sloping and a combination of plastic carton, fiberglass and sheet metal. In this study, a solar heating system is designed to reduce energy consumption in a poultry farm located in Ardestan city (a function of Isfahan province). The studied poultry farm located in Ardestan city is one of the functions of Isfahan province and has dimensions of 8 m in length and 5 m in width. The simulation is performed using TRNSYS software.Results and DiscussionThe results show that to achieve the technically optimal point (the point where there is maximum production from the sun and there is no energy dissipation from the sun), a collector surface equivalent to 26 m2 is required. In addition, these results show that a balance of 16 m2 is needed to balance the solar system with the auxiliary system.ConclusionBy installing 2 square meters of solar collector, 5.2% of the total energy can be supplied by the sun. To supply 100% of energy with the help of solar energy, 30 square meters of solar collector is needed. As the solar fraction increases, the system's ability to extract solar energy increases. Maximum production of solar energy (without energy wastage) is possible with a collector with an area of 26 square meters. To establish a balance between the use of solar energy and the use of the auxiliary system, a collector level of 16 square meters is needed.
Research Article
Agricultural waste management
M. Safari; M. A. Rostami
Abstract
In this study, the number of combine harvesters for harvesting of the wheat crop was 15 and included John deer combine harvesters equipped with straw threshers (Shiraz, Buchan and Hamedan) and Hamedan Barzegar specific chaff collectorr combineResults showed average yield, natural loss and combine loss, ...
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In this study, the number of combine harvesters for harvesting of the wheat crop was 15 and included John deer combine harvesters equipped with straw threshers (Shiraz, Buchan and Hamedan) and Hamedan Barzegar specific chaff collectorr combineResults showed average yield, natural loss and combine loss, were 1698.14 kg.ha-1, 2.39% and 4.92% respectively. In terms of losses rates in different parts of the combine, 43.49% was related to the chaff storage of the combine and 56.50% of it was related to the combine head. The natural loss rates was 2.39% in this province, the total combine loss was 5.18% that 40.44% of that was related to chaff storage and rest was related to combine head. The results showed that there was significant difference between the treatments in terms of field capacity and Chaff storage loss and purity percentage in 5% level. The total loss of Hamedan barzegar combine was 6.67% that was more than other combines. The chaff storage loss of Shiraz, Bookan, Hamedan and Hamedan barzegar combines were 0.87%, 2.64%, 0.78% and 4.28% respectively that showed significant difference in 5%level. There was significant difference between treatment in terms of total loss .With these results, using of Hamedan, Bookan,Shiraz and Hamedan barzegar combines with total losses 4.33%,4.33%,4.52% and 6.56% recommended respectively.
Research Article
Sh. Nourozieh
Abstract
IntroductionCotton as one of the most widely used products in various industries has always been considered by improving countries in agriculture. The applications of this plant range from food industry to military industry as well as textile and animal nutrition industry. It is predicted ...
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IntroductionCotton as one of the most widely used products in various industries has always been considered by improving countries in agriculture. The applications of this plant range from food industry to military industry as well as textile and animal nutrition industry. It is predicted that by 2025, the area under cotton cultivation in the world will reach more than 33 million hectares (FAO, 2016). Base on the growing population, it's clearly necessary to use machines in industries and other sectors to accelerate production and increase efficiency. Cotton also is no exception to this rule. The use of a machine can play and effective role in reducing harvest costs, and on the other hand, with timely harvesting, the losses from frost and early fall rainfall are also reduced.Material and methodsArmaghan cultivar is an early maturity cotton cultivar with high yield potential and good compatibility, which is introduced for conventional and secondary crops in Golestan, North Khorasan, Ardabil and central regions of Iran. The early maturity of this cultivar, providing the possibility of cotton cultivation after wheat harvest in different regions of Iran, reduces pests and diseases through the escape mechanism and completes the growth period in delayed planting. In this research, two types of picker machines were compared. One of the harvesting machines used in this study is a two-row self-propelled spindle picker machine and a second-hand picking machine is a two-row tractor semi-mounted toothbrush.Before harvesting by machine, it is necessary to use defoliator. This allows the seedcotton harvest with less trash and more clean. About ten to fifteen days after spraying the defoliator, the leafless plants are ready for machine harvesting. In this study, the leaves were counted before spraying and before harvest and the percentage of defoliation in each treatment was calculated and evaluated.The harvesting efficiency of machines, the losses of machines and fiber qualities for each harvester was measured. Results and discussionsThe results showed that the type of machine has a significant effect on the residues on the plant and the performance of the machine. But the loss on the ground is not affected by the type of machine and is almost the same in both machines. The mean comparisons show that the residues on the plant of the spindle harvesting machine are more than twice that of a toothbrush harvesting. In terms of fiber quality, no significant difference was observed in any of the qualitative properties, and both machines are on the same level. According to this study, for harvesting Armaghan cotton cultivator, the toothbrush harvesting is more suitable than the spindle picker machine.
Research Article
Agricultural waste management
V. Ebrahim Khanloo Sisi; N. Monjezi; M. Soleymani
Abstract
The purpose of this study was to identify and measure sugarcane losses in the sugarcane Agro-industry of Dehkhoda in 2021. The experiment was performed as a factorial Split Plot design based on randomized complete blocks (RCBD) with three replication. The first factor includes cultivars at 4 levels (IRC-12, ...
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The purpose of this study was to identify and measure sugarcane losses in the sugarcane Agro-industry of Dehkhoda in 2021. The experiment was performed as a factorial Split Plot design based on randomized complete blocks (RCBD) with three replication. The first factor includes cultivars at 4 levels (IRC-12, CP48-103, CP 73-21 and CP69-1062), the second factor includes harvest age at three levels (plant, Ratoon 1, Ratoon 2) and the third factor includes speed at three levels (3, 5, 7 km/h). The results showed that the highest yield in CP69-1062 variety was observed in the plant farm with average machine speed (144.33 tons per hectare). Also, the highest amount of sugarcane losses in cultivar CP48-103 in Raton II and with 7 km/h machine speed (3.32 tons per hectare), the highest amount of chopped sugarcane losses in cultivar CP48-103 in plant farm and with average speed (1.78 tons per hectare) was observed. According to the results under the interaction of cultivar and device speed, the highest amount of sugarcane losses in CP69-1062 cultivar and high speed (0.314 tons per hectare) as well as IRC-12 cultivar and high speed (0.308 tons in Hectares), and under the interaction of farm age and speed of the harvester, the highest amount of sugarcane losses was observed in Ratoon farm and the high speed of the harvester (0.300 tons per hectare).
Research Article
Post-harvest technologies
J. Abdi; A. Golmohammadi; Gh. Shahgholi; A. Rezvanivand fanaei
Abstract
IntroductionPeanut (Arachis hypogaea L.) is an annual plant of the legume genus, that is cultivated in 109 countries due to its high-quality oil and seed protein. The area under cultivation of this crop in Iran is 3000 hectares, and its average yield is 4 tons per hectare. Seed loss and physical damage, ...
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IntroductionPeanut (Arachis hypogaea L.) is an annual plant of the legume genus, that is cultivated in 109 countries due to its high-quality oil and seed protein. The area under cultivation of this crop in Iran is 3000 hectares, and its average yield is 4 tons per hectare. Seed loss and physical damage, including cracking and crushing of the seed during harvest, are significantly affected by threshing performance; Hence, during the last century, a lot of research has been carried out on different types of threshing methods and the design and development of different threshing machines. According to research on seed crops such as cereals and seeds, the factors of the rotational speed of thresher, threshing-concave distance, feeding rate, and shape of threshing teeth are the most important factors in the threshing efficiency and quality of threshed seeds. Since research on peanut threshing is limited and there is practically no combine-machine for this product available in global markets, this study aimed to investigate several working parameters of an experimental peanut thresher including the effect of sieve angle, sieve range of movement, and suction speed on the separation unit.Materials and MethodsRelevant experiments were conducted in Ardabil province, Parsabad Moghan region; Latitude and longitude 39.65 North and 47.91 East. To perform experiments and separate the seeds from the pods, a peanut threshing machine cultivar Nc2, which is cultivated in Ardabil and Gilan Agricultural Research Centers under agricultural conditions, was used. According to the aims of the research, several effective parameters in the performance of the machine including sieve angle, sieve movement range, and fan suction speed were investigated to obtain the best adjustment for maximum threshing performance and separation efficiency. It should be noted that the average seed weight per kg of peanut plant was between 300-400 gr and the moisture content of the seeds in the tested cultivar was 45%. For using the machine, the plants must first be dug up by workers and placed on the ground in a coupe, and then a worker must enter the plants through the feeder.Results and DiscussionIt was found that the effect of sieve angle, sieve movement range, and suction speed on separation efficiency and the peanut loss rate is significant at the level of one percent.According to the fact that with increasing the sieving angle, the speed of material movement on the sieve increases; the necessary opportunity to separate the straw from the seed is not provided. As the sieve movement range increases, the cleaning efficiency decreases rapidly. For better straw-seed separation, it is necessary to apply impact shocks to the products located on the sieve in a short period. As the range of movement increases, the time interval between impact shocks increases, and as a result, straw separation from seed is disrupted.The rate of peanut loss has increased with increasing sieve range and suction speed. The reason for this matter can be attributed to the fact that by increasing the suction speed and sieve movement range, the product spends less time on the sieve, and as a result, there is not enough time for proper separation of the product. Also, the higher speed may exceed the speed limit of the peanut seed and therefore cause the peanut to move out of the machine with the straw. Increasing the sieve movement range leads to a uniform movement of straw and seed on the sieve, while better separation of straw from the sieve requires dynamic shocks and sudden acceleration to the product which decreases with increasing the sieve movement range. The maximum farm capacity and material capacity belonged to the 5 degrees slope with 0.55 he.hr-1 and 509 kg.he-1 was achieved in the range of 3.5 cm and fan suction speed of 8 m.s-1, respectively. ConclusionsIt was concluded that the sieve movement range has the greatest effect, and the sieve angle has the least effect on the cleaning efficiency. Also, the sieve movement range has the greatest effect, and the angle of the sieve has the least effect on the rate of peanut loss.
Research Article
Agricultural systems engineering (greenhouse, fish farming, mushroom production)
R. Fathi; M. Ghasemi-Nejad Raeini; R. Hesampour
Abstract
Introduction: Environmental crises and resource depletion have adversely affected environmental resources and food security in the world. Therefore, given the forecast for global population growth in the coming years and the need to produce more food, attention to the issue of environment, energy consumption ...
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Introduction: Environmental crises and resource depletion have adversely affected environmental resources and food security in the world. Therefore, given the forecast for global population growth in the coming years and the need to produce more food, attention to the issue of environment, energy consumption and sustainable production is of great importance. The purpose of this study was to evaluate the pattern of energy consumption, environmental impacts and optimization of the studied Energy indicators in dairy cattle breeding industrial units in Khuzestan province. Materials and Methods: This research was conducted in Khuzestan province located in the southwest of Iran. Energy indicators including energy ratio, energy efficiency, specific energy and net energy were used to determine and analyze the relationships between output and input energy. In addition, the life cycle assessment methodology also was used to assess the environmental impact. Life cycle assessment includes goal statement, identification of inputs and outputs, and a system for assessing and interpreting environmental impacts, and can be a good yardstick for assessing environmental issues related to product production. The life cycle assessment method used in this study was CML-IA baseline V3.05, which includes four steps of selecting and classifying impact categories, characterizing effects, normalizing, and weighting. Data envelopment analysis method with Anderson-Peterson model was used for optimization. This method identifies the most efficient production unit and makes it possible to rank all farms in the region. In this study, each production unit (each farm) was considered as a decision unit (DMU) and the efficiency of production units was determined based on CCR and BCC models for each farm.Results and discussion: The results showed that the input and output energies per cow per day were 173.34 and 166 mj, respectively. Livestock feed and electricity with 65.47% and 65.47%, respectively, and the oil used for tiller-scraper lubrication of fertilizer collection with 0.01% had the lowest input energy. Energy efficiency, energy efficiency, specific energy and net energy were calculated as 0.95, 0.13 kg/mJ, 7.51 mJ/kg and -7.20 MJ per cow, respectively. The results showed that in all groups of the effect, except for the non-living discharge potential related to fossil fuels, animal feed had the highest environmental emissions. In the impact group of abiotic discharge potential, animal feed, machinery and livestock equipment had the highest environmental impact. In the group of non-living discharge potentials related to fossil fuels, electricity had the highest effect. The number of efficient units was determined using CRS model, 7 units and the average production units in terms of efficiency was 0.78. In the BCC model, there were calculated with 20 production units with high efficiency and the average efficiency of the scale was computed equal to 0.78. In most of the effect groups, animal feed and in the effect group, non-living discharge potential, animal feed, machinery and livestock equipment had the highest environmental effects. According to the results, animal feed had the highest environmental emissions in all impact groups except non-living discharge potential related to fossil fuels.Conclusion: In dairy farms in Khuzestan province, animal feed and electricity had the highest energy consumption. In most of the effect groups, animal feed and in the effect group, inanimate discharge potential, animal feed, livestock machinery and equipment had the highest environmental effects. Due to the length of the heat period and the intensity of the solar flux, the use of solar panels on the roof of the farm to supply the required electricity can reduce the consumption of non-renewable energy and reduce the intensity of radiation under the roof of the Livestock.
Research Article
Bioenergy
M. Nowroozipour; R. Tabatabaei koloor; A. Motevali
Abstract
IntroductionThe growing population of the world has led to an inevitable increase in energy demand, and this, in addition to the depletion of non-renewable energy sources, can lead to many environmental problems. Given the importance of environmental impacts and the development of renewable energy, the ...
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IntroductionThe growing population of the world has led to an inevitable increase in energy demand, and this, in addition to the depletion of non-renewable energy sources, can lead to many environmental problems. Given the importance of environmental impacts and the development of renewable energy, the use of wind can be a very reliable source for generating electricity.Materials and MethodsThe present study investigates the environmental effects of electricity generation during the life cycle of wind farms (Kahak and Aqkand) during the construction to operation of these power plants and the cumulative exergy demand index. In the present study, a functional unit of one kilowatt of electricity was selected and the data were analyzed in SIMAPRO software by IMPACT2002 + method in the form of 15 Midpoint indicators and four final indicators.Results and DiscussionThe results showed that the stage of raw materials and production has the highest impact on the creation of intermediate indicators, which is due to the extraction, manufacture and production of parts such as steel casting from non-renewable energy and activities such as high temperature welding. Also, the total environmental index of Aqkand and Kahak wind power plants for 1 kWh of generated electricity was 5.84 and 4.45 (μPt), respectively, of which 3.02 and 2.31 (μPt) belong to the category, respectively Damage to human health. Also, the study of cumulative exergy demand index showed that non-renewable-fossil resources had the largest share in exergy demand (0.15 MJ) to produce one kilowatt of electricity generated from power plants.ConclusionIn the present study, the results showed that the stage of raw materials and production in two power plants was about 70% effective in creating various respiratory effects, 60% in creating human health potential, 25% in creating acidification groups and global warming. Also, the installation phase of 17% in Aqkand power plant and 16% in Kahak power plant was effective in creating climate change and between 14% and 26% in creating other environmental groups.
Research Article
Modeling
H. Soltanali; M. Khojastehpour
Abstract
Introduction: With the advent of new automation and mechanized technologies in the production and processing of agricultural products in Iran to accelerate the process of food supply, benefit from appropriate management models in the field of maintenance is unavoidable to maintain and improve the operational ...
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Introduction: With the advent of new automation and mechanized technologies in the production and processing of agricultural products in Iran to accelerate the process of food supply, benefit from appropriate management models in the field of maintenance is unavoidable to maintain and improve the operational reliability of agricultural machinery, tools, and equipment. Furthermore, proper management of the operation and maintenance of various physical assets in the agricultural industry is one of the most important requirements due to the importance of their readiness / high availability in the seasons of planting, holding, and harvesting of agricultural products compared to other continuous production processes.Materials and Methods: To achieve an efficient model in the field of maintenance, the following steps have been contemplated: a) Review and identify the most important criteria and sub-criteria driving the maintenance management, based on the previous literature and the experts’ opinion, b) Evaluate and prioritize the main criteria and interactions between their sub-criteria using the Best-Worst Method (BWM) and finally, c) Provide the improvement solutions in maintenance management for Iranian agro-industries. We decided to employ BWM because in, compared to similar methods, it (i) provides more reliable pairwise comparisons, (ii) reduces possible anchoring bias that may occur during the weighting process by respondents, (iii) is the most data-efficient method, and (vi) provides multiple optimal solutions, which increases the flexibility when it comes to accessing the best point of weight. The process of weighting by BWM is summarized in five steps, as follows: 1) Determine a set of evaluation criteria by the experts/decision-makers, 2) Identify the most important (Best) and the least important (Worst) criteria by the experts/decision-makers, each of whom might have their own Best and Worst, 3) Determine the preference of the Best over all the other criteria with a number from 1 to 9 (where 1 represents equally important and 9 represents extremely more important), 4) Determine the preference of all the decision criteria over the Worst, and 5) Compute the optimal weightsResults and Discussion: According to preliminary surveys, the most important criteria in the excellence maintenance model were “organizational management”, “human-related factors”, and “organizational aspects”, respectively. The results of the BWM revealed that the sub-criteria such as "top management support," "fund allocation and inventory resource management," and "appropriate maintenance strategies" have the greatest impact on maintenance management in agro-industries with the global weights of 0.108, 0.075, and 0.067, respectively. Furthermore, the findings of this study were compared to previous research in the field of agricultural and production system maintenance models.Conclusions: The study's findings could assist managers in revising and developing their maintenance management models in the agro-industries. To increase the accuracy of weighing criteria, future studies could calculate the interaction among criteria that were omitted in this study for the sake of simplifying the evaluation process, by the combination of DEMATEL and structural equations modeling.
Research Article
Image Processing
M. Nadafzadeh; A. Banakar; S. Abdanan; M. R. Zare bavany; S. Minaei
Abstract
IntroductionToday, machine vision systems are increasingly used in agriculture. The use of this technology in this field can help preserve agricultural resources while reducing manual labor and production costs. In the field of agricultural automation, the accurate detection of crop rows is recognized ...
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IntroductionToday, machine vision systems are increasingly used in agriculture. The use of this technology in this field can help preserve agricultural resources while reducing manual labor and production costs. In the field of agricultural automation, the accurate detection of crop rows is recognized as an important and challenging issue in terms of weed identification and automatic guidance of machines, and it is necessary to examine practical solutions in order to optimize it. Therefore, the purpose of this study is to accurately identify the basil cultivation rows in order to automatically route a robot in the cultivation field.Materials and MethodsIn one stage of this research, by taking six images in each growth period (third week, fourth week, and fifth week), weeds were removed between the crop rows; For this purpose, three different methods (area opening, dimensional removal and masking) were used. In another step, six images of crop rows without weeds were examined. Then, by performing image processing operations and implementing several routing algorithms (algorithms based on Hough transform, wavelet transform, Gabor filter, linear regression and the proposed algorithm of this study) on the images, the output of each of these algorithms compared to the specified ideal path by user was investigated. For this purpose, after capturing the image, all green areas were extracted from the image by performing the segmentation process. The weeds between crop rows were removed using three different methods during the growth period. In the next step, by applying each of the routing algorithms on the image, plant cultivation lines were identified and their equations were determined. Finally, the performance of the designed robot was evaluated using the most appropriate routing algorithm.Results and DiscussionAfter examining the performance of three different methods of weed removal in three periods of plant growth (third week, fourth week and fifth week), it was shown that in all periods of plant growth, the masking method had output with the lowest error rate compared to the ideal path, the shortest operation time (1.64 seconds on average) followed by the dimensional removal and the area opening methods. In the following work, by carefully comparing the routes detected by different routing algorithms compared to the ideal routes and according to the results of t-test at 5% probability level, the superiority of the studied routing methods was determined as follows: Proposed method, Gabor filter method, linear regression method, Hough transform method and wavelet transform method. Finally, the proposed algorithm with the highest rate of adaptation to the ideal path (with an average error of 3.65 pixels) and the shortest operation time (4.79 seconds) was selected as the most appropriate routing algorithm, and the performance of designed robot was evaluated using it.ConclusionAfter measuring and comparing the execution speed and error rate of each of the studied routing algorithms, according to the results, it was determined that the proposed method, Gabor filter method, linear regression method, Hough transform method and wavelet transform method are preferable to each other in the field of routing, respectively. Finally, it was shown that the designed robot using the proposed algorithm (with an average error of 3.65 pixels) has desired performance.AcknowledgmentThe authors express appreciation for the financial support provided by Tarbiat Modares University.
Research Article
Modeling
M. A. Hormozi; H. Zaki Dizaji; H. Bahrami; N. Monjezi
Abstract
Introduction The development of mechanization and machine technology has positive and negative consequences on the economic, social, and environmental conditions of each region. Conflicts in these dimensions complicate the selection and allocation of sustainable mechanization systems. Therefore, one ...
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Introduction The development of mechanization and machine technology has positive and negative consequences on the economic, social, and environmental conditions of each region. Conflicts in these dimensions complicate the selection and allocation of sustainable mechanization systems. Therefore, one of the basic questions in the selection of sustainable agricultural mechanization is how and with what methodology it is possible to propose the closest mechanization model to sustainability goals and to overcome the simultaneous contradictions of the three pillars of sustainability, considering the natural and technical limitations in agricultural production. What is the appropriate approach to consider its economic, environmental, and social dimensions? The current research aims to provide a framework in which the optimal mechanization model can be achieved in order to achieve the goals of agricultural sustainability so that it can be implemented and applied in a practical way, and it is possible to provide a model that addresses all the conflicting economic, social and environmental aspects. Quantitatively optimize the leveling of mechanization systems.Materials and Methods In this study, a framework is applied whereby contradictory goals of agricultural sustainability can be achieved. After selecting the indices and data collection, by combining Shannon entropy and TOPSIS, the similarity index was obtained for dimensions with two or more indices. The similarity indices and the values of the Benefit-Cost Ratio calculated for each system were considered as coefficients of three objective functions (economic, social and environmental) in multi-objective optimization. A multi-objective optimization model was applied to achieve sustainable agricultural mechanization patterns and solved using the NSGA-II algorithm. In order to validate the framework, mechanization systems in paddy production in the Ramhormoz region located in southwestern Iran were analyzed with constraints namely land, water, and machine. The five mechanization systems of paddy production included Puddled Transplanted, Un-puddled Transplanted, Water Seeded, Dry Seeded, and No-Till. Results and DiscussionPareto-optimal solutions of different scenarios with water and machine constraints showed that by using the framework, not only can sustainable goals be met to identify the optimal allocation of mechanization systems, but also the possibility of examining the effect of different scenarios under different constraints. The contradictions of the sustainability goals in the system of no-tillage and planting with paddling are highly visible. The no-tillage system with the highest score in the environmental dimension has the lowest score in the social and economic dimension. This modern system, developed in Ramhormoz for three years, has faced technical, economic, and social challenges. The cultivated area of this system in 2019 was 43 hectares. This system, despite the speed and ease of planting and its direct environmental benefits, due to the presence of wheat residues from previous cultivation and the warm and humid environment of cultivation, the possibility of mushroom development has increased, and due to periodic irrigation, weed outbreaks have greatly affected the satisfaction and profitability of this system. This point has also weakened the environmental indicators so that the highest consumption of poisons has been recorded in this system. The results of multi-objective optimization of sustainable rice mechanization systems in Ramhormoz city showed that the total surface area of optimal point systems is in the range of 2700 to 3200, which is close to the area under rice cultivation in Ramhormoz, which is 3310 hectares, and it indicates that the output of the model according to the restrictions applied is close to reality. The limitation of machines and water has made the two planting systems without paddling and dry farming have higher levels than other systems. Now, if the machine restriction is removed, despite the water restriction, the area under rice cultivation can be increased by about 700 hectares. This means that the requirement for the development of sustainable rice cultivation in Ramhormoz is to strengthen and support modern mechanized systems of no-tillage, drying, and planting with paddling, and they need to focus on systems with less water consumption, which are systems with a higher level of mechanization and the use of mechanized methods. If there is no water limitation and the model is subject to the current machine limitations, the optimal mechanization points with more levels rely on non-peddling plating and transplanting systems.Conclusions One of the most fundamental challenges in the development of mechanization is to identify the systems that establish the best balance between economic, social, and environmental dimensions and bring the most minor ecological damage while achieving the most economic and social benefits. Using the framework of sustainable mechanization can not only provide sustainable goals in identifying the best leveling of mechanization systems but also allows the researchers and implementers of the agricultural sector to examine the effect of different scenarios under different constraints. This framework can be used to find the optimal model of mechanization of all stages of tillage, planting, harvesting, and post-harvest in different geographical areas.
Research Article
Post-harvest technologies
H. Rezaei; M. Sadeghi
Abstract
IntroductionDue to the disadvantages of using chemical materials as pretreatment before grape drying, application of non-chemical methods that not only take the environmental issues into account but also increase the drying rate and increase the quality of the produced raisins is vitally important. The ...
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IntroductionDue to the disadvantages of using chemical materials as pretreatment before grape drying, application of non-chemical methods that not only take the environmental issues into account but also increase the drying rate and increase the quality of the produced raisins is vitally important. The high-humidity hot air impingement blanching (HHAIB) is one of the non-chemical methods that can be used as a suitable alternative for chemical pretreatment in grape drying. In this research, design, construction, and evaluation of a high-humidity hot air impingement blanching system is discussed in terms of drying kinetics of white seedless grape. The results are compared against control and chemical pretreatment.Materials and MethodsHigh-humidity hot air impingement blanching (HHAIB) systemThe HAIB system composed of the steam generator, steam transfer pipes, side channel pump, closing and opening valves, air recycling channel, electric air heater, hot-humid air transfer channel, pretreatment chamber, hot-humid air distribution chamber and nozzles, temperature and humidity sensors and controllers. The performance of the system depends on the humid air temperature, the output fluid velocity from the nozzle, the distance of the nozzles from the product surface, as well as the diameter and arrangement of the nozzles. For the optimal design of the nozzles’ array, the relationships of the heat transfer coefficient, air mass flow, and blowing power were considered. Application of the HHAIB pretreatment and evaluation of its effect on the grape drying process Experiments were conducted to investigate the effect of temperature and duration of high-humidity hot air impingement blanching pretreatment on kinetics of grape drying. Two-factor completely randomized factorial design with three replications was used to analyze the data.According to the studies, the air at temperatures of 90, 100, and 110°C, velocity of 10 m s-1, and relative humidity in the range of 40%-45% was applied to the product. Pretreatment durations were also considered to be 30, 60, 90, 120, and 150 s. Experiments were conducted at three replicates and control treatment and acid pretreatment were also used to compare the drying process. Due to the high quality of shade-dried raisins, the process was studied using this method.The effect of the pretreatment duration on drying kinetics of white seedless grapes was assessed by variations in moisture ratio and drying rate with respect to time and determination of the effective diffusivity of water.For color evaluation of produced raisins, after measuring L*, a*, and b* values, chroma (C), hue angle H°, and total color difference (ΔE) parameters were calculated.Results and DiscussionThe comparison of the drying process among control, chemical, and HHAIB showed the positive efficacy of the HHAIB on the drying rate of grapes. Compared to the fresh grapes, the increase in drying rate under the influence of the HHAIB varied from 8% for the duration of 30 s at 90 °C to 68% for the duration of 150 s at 110 °C. The values of diffusion coefficient of grapes for the HHAIB pretreatment at temperatures of 90, 100, and 110 °C and durations of 30, 60, 90, 120, and 150 s, as well as for the control and chemical pretreatments were determined. The values of the coefficient changed from 2.28×10-10 m2 s-1 for 30 s of applying pretreatment at 90 °C to 3.53×10-10 m2 s-1 for 150 s of the application of the pretreatment at 110 °C. The highest value of this coefficient (7.46×10-10 m2 s-1) was related to the chemical pretreatment. The value of the diffusion coefficient increased with increasing the temperature and duration of the HHAIB pretreatment. In general, this increase in the drying rate and the diffusion coefficient can be attributed to the effect of the HHAIB pretreatment on the texture and destruction of the cell wall, as well as the microcracks created on the skin of the grapes. Moreover, the findings revealed that in comparison with the hot air temperature the duration of the HHAIB pretreatment was more effective in enhancing the drying rate. Moreover, based on the color analysis, temperature of 110 °C and duration range of 90-150 s were achieved as suitable conditions for applying pretreatment.ConclusionThe HHAIB pretreatment by combining the benefits of the hot air blanching with jet technology affects the texture and skin of grapes and accelerates the drying process and increases the quality of the produced raisins. However, the correct application of this pretreatment is depended on the proper design of the system and appropriate conditions including duration, temperature, and relative humidity. The results of drying kinetics showed that the drying rate increased with increasing the temperature and duration of the pretreatment. The findings indicate that the HHAIB pretreatment could improve the color indices of the raisins. The resulted increase in the drying rate and acceptable quality of the final product provides a basis for use of the HHAIB in larger and industrial scales.
Research Article
Precision Farming
M. Saadikhani; M. Maharlooei; M. A. Rostami; M. Edalat
Abstract
Remote sensing is the science of data acquisition about an object, a complication, or phenomena related to a geographic location without physical contact with them. The use of remote sensing data is rapidly expanding. Researchers have always been interested in classifying land coverage phenomena accurately ...
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Remote sensing is the science of data acquisition about an object, a complication, or phenomena related to a geographic location without physical contact with them. The use of remote sensing data is rapidly expanding. Researchers have always been interested in classifying land coverage phenomena accurately using multispectral images. One of the factors that reduces the accuracy of the classification map is the existence of uneven surfaces and high-altitude areas. The presence of high-altitude points makes some difficulties for the sensors to obtain accurate reflection information from the surface of the phenomena. Radar imagery with the use of digital elevation model (DEM) is effective in identifying and determining altitude phenomena. Using specifications of two completely different sensors in order to take the advantageous of each sensor capabilities is called image fusion technique. In this study, the feasibility of employing the fusion technique to improve the overall accuracy of classifying land coverage phenomena using time series NDVI images of Sentinel 2 satellite imagery and PALSAR radar imagery of ALOS satellite was investigated. Also, the results of predicted vs. measured area of fields under cultivation of wheat, barley and canola were studied.Materials and MethodsThirteen Sentinel-2 multispectral satellite images with 10-meter spatial resolution from the Bajgah region in Fars province dated from Nov 2018 to June 2019 were downloaded at the L1C processing level to classify the cultivated lands and other phenomena. Ground truth data were collected through several field visits using handheld GPS to pinpoint different phenomena in the region of study. Seven classes of land coverage and phenomena include 1) Wheat 2) Barley 3) Canola 4) Tree 5) Residential regions 6) Soil and 7) others were distinguished in the region. After preprocessing operations such as radiometric and atmospheric corrections using predefined built-in algorithms recommended by other researchers in ENVI 5.3 and cropping the region of study (ROI) from the original image, the Normalized Difference Vegetation Index (NDVI) was calculated for each individual image. The DEM was obtained from the PALSAR sensor radar image with the 12.5-meter spatial resolution of the ALOS satellite. After preprocessing and cropping the ROI, a binary mask of radar images was created using threshold values of altitudes between 1764 and 1799 meters above the sea level in ENVI 5.3. The NDVI time series were then composed of all 13 images and integrated with radar image by pixel-level integration method. The purpose of this process was to remove the high-altitude points in the study area that would reduce the accuracy of the classification map. The image fusion process was performed using ENVI 5.3 as well. The support Vector Machine (SVM) classification method was employed to train the classifier for both fused and unfused images as promoted by literatures.To evaluate the effectiveness of deploying image fusion, the Overall accuracy, Commission and Omission errors were calculated using a Confusion matrix. To study the accuracy of the estimated area under cultivation of main crops in the region vs. actual measured values of the area, regression equation and percentage of difference were calculated.Results and DiscussionVisual inspection of classified output maps shows the differences in classifying similar classes such as buildings and structures versus regions covered with bare soil and, lands under cultivation versus natural vegetation in high altitude points in the fused images when comparing them to the unfused images. These visual evaluations were verified by statistical metrics as well. The SVM algorithm in fusion mode provided 7.5% higher accuracy versus the non-fused image with 98.06% accuracy and 0.97 kappa coefficient. As stated earlier, considering the similarities between the soil class (stones and rocks in mountains) and manmade buildings and infrastructures increase the omission error and miss classification in unfused image classification. The same problem was arisen, for crop lands additionally, due to shallow vegetation at high altitude points. These results were consistence with previous pieces of literature that reported the same miss classification in analogous classes. Considering the predicted vs. measured area under cultivation of wheat and barley show that predicted values were overestimated by 3 and 1.5 percent respectively but for canola, the area was underestimated by 3.5 percent with respect to annotations.ConclusionThe main focus of this study was employing the image fusion technique to improve the classification accuracy of satellite imagery. Integration of PALSAR sensor data from ALOS radar satellite with multi-spectral imagery of Sentinel 2 satellite, was acceptably enhanced the classification quality of output maps by eliminating the high-altitude points and biases due to rocks and natural vegetation at hills and mountains. Statistical metrics such as overall accuracy, Kappa coefficient, commission and omission errors also confirmed by the visual findings in fused vs. unfused classification maps.
Research Article
Post-harvest technologies
S. Sharifi; M. H. Aghkhani; A. Rohani
Abstract
The loss problem on-fields and paddy milling factory dryers have always been challenging issues in the rice industry. Different losses forms may occur in brown rice depend on the field and factory conditions. To reduce the losses, proper management during pre-harvest, harvesting, and post-harvest operations ...
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The loss problem on-fields and paddy milling factory dryers have always been challenging issues in the rice industry. Different losses forms may occur in brown rice depend on the field and factory conditions. To reduce the losses, proper management during pre-harvest, harvesting, and post-harvest operations are essential. In this study, different on-field and factory drying methods were investigated to detect different forms of brown rice losses.Obviously, the importance of food security has always been matter in developing countries. An Identifying losses source on the fields and factories is one way to achieve food security. Consequently, drying on the fields for 5h and, subsequently, stacking and plastic covering are not recommended in terms of effect on increasing the percent of brown rice losses. Also, in the factory dryers, it is recommended using the 3-stage with 10h tempering at 40 °C and 0.5 m s-1 air speed due to the importance of scheduling in the management of the dryer unit.
Research Article
Precision Farming
R. Azadnia; A. Rajabipour; B. Jamshidi; M. Omid
Abstract
Introduction
One of the most frequently consumed fruit in all over the world is apple. An apple fruit includes large source of minerals, fiber and several biologically compounds such as vitamin C, special phenolic compounds (natural antioxidant). The amount of nutrients plays a significant role in the ...
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Introduction
One of the most frequently consumed fruit in all over the world is apple. An apple fruit includes large source of minerals, fiber and several biologically compounds such as vitamin C, special phenolic compounds (natural antioxidant). The amount of nutrients plays a significant role in the growth, reproduction and performance of agricultural products and plants. By predicting these elements, chemical inputs can be accurately managed. Thus, timely and accurate monitoring and management of crop nutrition status are crucial for recommended fertilization, yield increase, and quality improvement, whilst by reducing the amount of chemical fertilizers applied, the risk of environmental degradation can be reduced. In crop plants, leaf samples are typically analyzed to diagnose nutrient deficiencies and imbalances, as well as to evaluate the effectiveness of current nutrient management programs. Thus, the main aim of this study was to non-destructively estimate the level of Nitrogen (N), Phosphorus (P) and Potassium (K) elements of apple tree leaves using Visible/Near-infrared (Vis/NIR) spectroscopy at wavelength range of 500 to 1000 nm coupled with chemometrics analysis.
Materials and Methods
This research investigated the potential of the Vis/NIR spectroscopy system with chemometrics analysis for predicting NPK nutrients of apple trees. To do so, 80 leaf samples of apple trees were randomly picked and transferred to the laboratory for spectral measurement. The Green-Wave spectrometer (StellarNet Inc, Florida, USA) utilized to collect the spectral data. In the next step, the spectral data were transferred to the laptop using the Spectra Wiz software (StellarNet Inc, Florida, USA). For this purpose, spectroscopy of apple tree leaf samples was done in intractance mode. Furthermore, ten reflectance spectra were captured randomly on each apple tree leaf at different points. The averaged spectrum was used to determine the reflectance (R). The data was then transformed into absorbance (log 1/R) for chemometrics analysis. The NPK contents were measured using reference methods following spectroscopy measurements. Then Partial Least Square (PLS) multivariate calibration models were developed based on reference measurements and spectral information with different pre-processing techniques. In order to remove the unwanted effects, various pre-processing methods were used to obtain an accurate calibration model. To evaluate the proposed models, Root Mean Square Error of calibration and prediction sets (RMSEC and RMSEP), as well as correlation coefficient of calibration and prediction sets (rc and rp), and Residual Predictive Deviation (RPD) were calculated.
Results and Discussion
The statistical metrics were calculated for evaluation of PLSR model. The results indicated that the PLSR model could efficiently predicted the NPK contents with a satisfactory accuracy. The best developed model based on the standard normal variation pre-processing method in combination with the second derivative (SNV+D2) with the values of rc= 0.9859, RMSEC=0.028%, rp=0.978, RMSEP=0.034% and RPD of 7.47 was related to nitrogen prediction. The best model for prediction of P content resulted in rc= 0.967, RMSEC=0.0051%, rp=0.958, RMSEP=0.0057% and RPD of 5.96. Also the PLSR model based on MSC+D2 preprocessing method resulted in the in rc= 0.984, RMSEC=0.017%, rp=0.976, RMSEP=0.021% and RPD of 7.10, indicating the high potential of PLSR model in prediction of K content. Moreover, the weakest model was related to estimation of P content based on data without pre-processing with rc = 0.774, RMSEC = 0.013%, rp = 0.675, RMSEP = 0.018% and RPD value of 1.87. Based on the obtained results, the proposed PLSR model coupled with preprocessing methods was able to predict the nutrients content with high precision.
Conclusion
Field spectroscopy has recently gained popularity due to its portability, ease of use, and low cost. Consequently, the use of a portable system for estimating nutrient levels in the fields can significantly reduce time wastage and laboratory expenses. Therefore, according to the ability of the Vis/NIR spectroscopy technique and according to the obtained results, this method can be used to implement a field portable system based on Vis/NIR spectroscopy in order to estimate the Nutrient elements needed by apple trees in the orchards and increased the productivity of the orchards.
Research Article
Precision Farming
J. Nasrollahi Azar; R. Farrokhi Teimourlou; V. Rostampour
Abstract
IntroductionPrecision agriculture is an approach to farm to ensure that the crops and soil receive exactly what they need for optimum health and productivity. Precision agriculture offers the potential to automate and simplify the collection and analysis of information. It allows management decisions ...
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IntroductionPrecision agriculture is an approach to farm to ensure that the crops and soil receive exactly what they need for optimum health and productivity. Precision agriculture offers the potential to automate and simplify the collection and analysis of information. It allows management decisions to be made and quickly implemented on small areas within larger fields. One of the advanced and inexpensive methods that provides a lot of information about the soil with the shortest time and lowest cost is measuring acoustic signals with cone penetrometer. The texture of the soil determines the percentage of the constituents of the mineral part of the soil such as sand, silt and clay.An acoustic penetrometer was developed to provide an accurate method for determining the soil texture. This system uses a microphone to record the sound produced through the cone-soil communication and correlates this data with the soil texture.Materials and MethodsAn acoustic cone penetrometer (ACPT) was designed to determine if there is a relationship between the sound produced at the cone-soil interface and soil particle size. Three types of cones with angles of 30, 45 and 60 degrees and diameter of 20.27 mm and rod length of 300 mm according to ASAE standard S313.3 FEB1999ED (R2013) were used to determine the relationship between sound and soil texture and to choose the best angle. A microphone (20-20,000 Hz) was used to record the audio signals produced from the soil, suitable for fast dynamic responses. Audio signals were stored online through the oscilloscope section of Matlab software. To create the controlled vertical movement of the cones, a mechanical mechanism with electronic controllers was designed. This mechanism can be connected on the rails of the soilbin located in Urmia University. In this system, a 5 hp electric motor with a gearbox, an inverter to control the rotational speed of the electric motor and a digital ruler to record vertical movement were used. Soil samples were tested in 5 gallon bins.Acoustic signals received from microphone were processed in the time-frequency domain using wavelet transform. In this research, Daubechi function type 3 is used to analyze acoustic signals. It is not possible to use processed acoustic signals directly in statistical analysis. For this reason, appropriate features should be extracted from them. From the 30 features of time domain signals, the most effective and main features include; SUM, Max, RMS, average, Var, kurtosis and Moment4. They were ranked using the feature selection section of WEKA 3.9.2 software in order to avoid increasing the volume of calculations and increasing processing speed and reducing errors. In order to analyze the signals related to several different tissues and finally distinguish the difference between these three types of tissues, the characteristic vector of the sub-signals should be analyzed.Results and DiscussionTo select the best type of cone using WEKA software, the number of features in d1 sub-signals was higher for the 45 degree cone, and it can be concluded that this cone has more ability to recognize the data.The average values of characteristics in clay, loam, and sand had an increasing trend respectievely with a significant probability of 1% and 5%.Acoustic signals for clay soil, which has a heavy texture and small particles, have a minimum amplitude, and for loamy and sandy soil, they were observed as medium and maximum, respectively. This will cause the values of the selected features of clay soil to be low, and as a result, the average values, variance, and standard deviation. They would be higher for loamy and sandy soil which have larger particles. In this way, as the size of the soil particles increases, hitting the cone wall would become heavier and would affect the frequency and amplitude of the signal, which will increase the values of the signal amplitude and, as a result, increase sum, max and mean.ConclusionAmong the sub-signals, the maximum effect of soil texture type changes was related to d1 sub-signals for the 45̊ cone, and these signals had more potential to identify the soil texture type. Among the features, sum, average, VAR and RMS were significant at 1% probability levels. Therefore, these features in the mentioned sub-signal have more potential to detect the type of soil texture. Also, the effect of soil texture change on Moment and Kurtosis characteristics was significant at 5% probability levels.
Research Article
Precision Farming
N. Bagheri; A. Sheikhi Garjan; M. Safari
Abstract
IntroductionAbout 30% of the annual losses of agricultural products are caused by pests, diseases and weeds. Spraying is still the most common method of their control. At present, all kinds of manual and tractor-mounted sprayers are used for spraying. The use of manual spraying is associated with high ...
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IntroductionAbout 30% of the annual losses of agricultural products are caused by pests, diseases and weeds. Spraying is still the most common method of their control. At present, all kinds of manual and tractor-mounted sprayers are used for spraying. The use of manual spraying is associated with high consumption of poison, damage of farmer and product and very low work efficiency. Tractor-mounted sprayers are more efficient than manual sprayers and require less labor, but their use involves problems such as compacting the soil and crushing the product. In recent years, UAV sprayers have been used to spray farms and orchards. UAV spraying can increase the spraying efficiency by more than 60% and reducing 20-30% of poison volume. According to the capabilities of the UAV sprayer and problems of the current spraying methods, the purpose of this research is to evaluate the performance of the UAV sprayer to control the canola aphid and compare its results with turbo liner sprayer.Materials and MethodsIn the present research, the UAV sprayer as a new method of spraying to fight canola aphids was technically and economically evaluated and its results were compared with the turbo liner sprayer (conventional method of spraying in the region). The design was replicated in triplicate as a completely randomized design. Field tests were conducted on the canola crop at the stemming stage when at least 20% of the plants were infected. The measured parameters included drift, spraying quality, field capacity, field efficiency, energy consumption and spraying efficiency.Results and DiscussionBased on the results, the amount of consumption volume distributed by UAV sprayer and turbo liner sprayer was equal to 11.1 and 187.6 liters per hectare, respectively. The particle drift in spraying with UAV sprayer and turbo liner sprayer were, 53.3 and 80%, respectively. The quality coefficient of UAV sprayer and turbo liner sprayer were 1.15 and 1.21, respectively. So, the farm efficiency of the UAV sprayer and turbo liner sprayer was equal to 51.4% and 32.3%, respectively. Based on the results of the analysis of variance the average density of aphids before spraying, there was no statistically significant difference in different treatments. However, in three, seven and 14 days after spraying, there was a significant difference between the control treatment and the spraying treatments; So the density of aphids in the plots sprayed with UAV sprayer and turbo liner sprayer after spraying was less than 100 aphids per stem, but in the control treatment, the density varied between 250-700 aphids per stem. A comparison of the average efficiency of the UAV sprayer and turbo liner sprayer with the t-test showed that both sprayers had acceptable results in controlling the canola aphid population and in the 14 days after spraying, the efficiency of the UAV sprayer was higher than that of the turbo liner sprayer.Conclusion- The volume consumption used by the turbo liner sprayer was 17 times more than that of the UAV sprayer. - The drops drift in spraying with the turbo liner sprayer was about 34% more than the drift of the UAV sprayer.- The field efficiency of the UAV sprayer was 59.1% more than the field yield of the turbo liner sprayer.- The energy consumption of the turbo liner sprayer per hectare was 7 times the energy consumption of the UAV sprayer. - The efficiency percentage of UAV sprayer 14 days after spraying obtained 92.7 %. Due to the lower drift, volume consumed, the energy consumed, and the higher efficiency and spraying quality, this method is recommended to control canola aphid. - It is recommended that, the Tee-jet nozzles are suitable for controlling the aphid population. To improve the performance of the UAV sprayer for controlling aphid, a flight height of 1-1.5 meters from the top of the crop, a flight speed of less than 7 m/s, and spraying speed of less than 4 m/s are recommended. Also, with field spraying in the earlier stage, it is possible to prevent the spread of the pest in the stemming stage and further spread of the pest.
Research Article
Design and Construction
M. Rezaei; J. Khodaei; B. Astinchap
Abstract
Introduction
Due to the increasing need for agricultural products, protection of products against pathogens and preventing them from being wasted is important. Study on droplets charging systems are important because of its influence on the reduction of chemicals and the increase of droplet deposition ...
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Introduction
Due to the increasing need for agricultural products, protection of products against pathogens and preventing them from being wasted is important. Study on droplets charging systems are important because of its influence on the reduction of chemicals and the increase of droplet deposition on the target. Conventional sprayers in Iran have many disadvantages such as drift, environmental pollution, lack of complete and homogeneous coverage on spraying surface, phytotoxicity and crop losses. Therefore, evaluation of new spraying methods and using a variety of electrical sprayers as alternatives to conventional spraying is essential. The aim of this study is design, construction and optimization of performance of electrodynamic head of atomizer motorized knapsack sprayer, and study of the effects of the parameters of angle of the target position, spraying distance and wind speed on the performance of the electrodynamic head in the atomizer.
Materials and Methods
Experiments were performed in agricultural machinery workshop at The Department of Biosystems Engineering of University of Kurdistan, Iran, with atomizer motorized knapsack sprayer equipped with electrodynamic head. The effect of some factors, including wind speed, angle of the target position and spraying distance to the target were investigated on deposition and coverage percentage, uniformity of spraying. These effects were investigated to determine the uniformity coefficient of total spraying. Design Expert 8.0.6 Trial software was used to design the experiments and to analyze data based on central composite design. The investigated factors and levels were: distance of nozzles from the target (at three levels of 2, 4, and 6 m), angle of the target position (at three levels of 0, 45, and 90 degree), and wind speed (at three levels of 2.5, 3, and 3.5 m/s). Water sensitive paper cards were used to evaluate the quality of spraying spread. The cards were scanned and magnified with an Olympus SZX12 Stereo Microscope equipped with objective lens of X1 and total magnification of 7X. The characteristics of droplets size were determined using MountainsMap Trial and Deposit Scan softwares.
Results and Discussion
The maximum value of the total spraying uniformity coefficient is equal to 1.95 for the spraying angle of 0 degrees, the distance of 6 meters and the speed of 3.5 meters per second. Meanwhile, the lowest value of the spray uniformity coefficient of 1.18 was obtained in the test conditions of 90 degrees, the distance of 2 meters and speed of 2.5 meters per second respectively. Based on analysis of variance for the interaction model of two factors (F value less than 0.0001, explanation coefficient 0.9435, absolute explanation coefficient 0.9174, standard deviation 0.0564 and coefficient of variation 3.609%). It can be stated this model is highly accurate in predicting the uniformity of the total spraying, and the linear components of spraying angle and spraying distance, as well as the interaction of spraying angle × spraying distance and spraying distance × wind speed had a significant effect on the uniformity of the total spraying (p<0.05). Nevertheless, the linear component of wind speed and the interaction between wind speed and spray angle had no significant effect on the changes in the uniformity coefficient of the total spray. According to the variance analysis table (F-value values), the effect of spraying distance on the spraying uniformity coefficient is far greater than the effect of spraying angle. It has been observed that by increasing the spraying distance and decreasing the spraying angle, the spraying uniformity coefficient will increase. It can also be stated that the linear components of spraying angle and spraying distance, the interaction component of spraying angle × spraying distance and the square power of the components of spraying distance and air speed have a significant effect on the coverage of the spraying surface. The values of R2, Adj-R2, CV and Press for the model adapted to the test data of leaf surface coverage percentage were obtained as 0.9929, 0.9865, 4.87% and 188.61%, respectively. Also, the amount of misfit for the mentioned mathematical model is significant (p<0.05). This indicates the appropriate accuracy of the model in predicting the amount of water sensitive paper cover. Among the three input variables, the spraying distance has the greatest effect on the amount of water sensitive paper cover.
Among the three input variables, the spraying distance has the greatest effect on the amount of water sensitive paper cover. At high levels of the spraying angle, especially at the spraying angle of 90 degrees, the spraying amount has decreased with the increase of the distance. At the spray angle (angle of the target position) of 90 degrees, by increasing the distance from 2 to 4 meters, the spray uniformity coefficient has increased from 1.18 at a wind speed of 2.5 ms-1 to 1.84 at a wind speed of 3.5 ms-1. Increasing the distance between the sprayer and the target decreased the amount of surface coverage on the target. The uniformity of particle settlement on the bottom surface of the target was relatively the same in electrodynamic spraying. This is despite the fact that at low levels of the spraying angle (for example zero-degree angle) the spraying amount increases at first with the increase of the spraying distance from 2 to 3 meters and then decreases with a sharp slope. According to the contours of spray surface changes, all wind speed levels in the spray distance range of 4 to 6 m with the increase of the spray angle, show no change in the spray surface value (p< 0.05). Meanwhile, in the spray distance range of 2 to 4 m, with the increase of the spraying angle, the amount of spraying surface has increased significantly (p<0.05).
Conclusion
In order to improve the performance of atomizer motorized knapsack sprayer, an electrodynamic spraying head was designed and built, and its performance was optimized using the central composite design of the response surface method(RSM). During the research process, the influence of the independent parameters such as the distance of the nozzle in relation to the target, the angle of the target position and the wind speed on the variables, including spraying uniformity, the percentage of the spraying surface and the percentage of changes in the total spraying coefficient were discussed and investigated. The results of the research led to the determination of the 3.5 ms-1 wind speed, 2.5 m sprayer distance and 90º spraying angle with 0.792 desirability, which were considered as the optimal performance conditions of the electrodynamic spraying head. The results of laboratory validation for optimal conditions show that the amount of uniformity of total spraying and the percentage of spraying surface are equal to 28.27% and 1.65%, respectively.
Research Article
Post-harvest technologies
V. Kahrizi; E. Ahmadi; A. R. Shoshtari
Abstract
Introduction
Today, the increasing demand of consumers for high-quality products has led to the development of new technologies for the quality assessment of agricultural products. Iran is ranked the 9th in the world in terms of orange production. Annually, large quantities of agricultural products ...
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Introduction
Today, the increasing demand of consumers for high-quality products has led to the development of new technologies for the quality assessment of agricultural products. Iran is ranked the 9th in the world in terms of orange production. Annually, large quantities of agricultural products are degraded due to mechanical and physical damage during various operations such as harvesting, packaging, transportation, sorting, processing, and storage. This study is performed to identify natural frequencies and vibration modes of the Thomson orange fruit in small and large groups using finite element modal analysis by ANSYS software. In addition, physical properties including mass, volume, density and main dimensions were measured and mechanical properties were determined using Instron Texture Profile Analysis. Dynamic behavior of the orange fruit was simulated using the pendulum impact test. Next, the obtained impact was applied to the orange fruit by force gauge and three-axis accelerometer sensors in both polar and equatorial directions. The three-dimensional geometric model of the orange fruit was drawn in the ANSYS software. After meshing and applying the boundary conditions, the first 20 modes and corresponding natural frequencies were obtained. Since the objective of this study was to identify the natural frequencies of the orange fruit, it was considered free to move and rotate in space. The results showed that the natural frequencies of orange fruit are in the range of 0 to 248.41 Hz. Knowledge of the texture characteristics and dynamic behavior of horticultural products is essential for the design and development of agricultural machinery. Also, the design and development of agricultural machinery are directly related to the biological properties of agricultural products.
Materials and Methods
In the present study, Thomson orange variety is used. For experiments, a certain number of oranges were harvested from the Citrus and Subtropical Fruits Research Institute, Ramsar (50° 40′ E and 36° 52′ N). Performing finite element analysis needs knowing the physical and mechanical properties of the flesh and skin of the orange fruit. The physical and mechanical properties of the tested samples include geometric dimensions, modulus of elasticity, Poisson’s ratio, and density. In the present study, the dynamic behavior of orange fruit under dynamic loads was investigated by performing an impact test using a pendulum. The orange fruit was hung from the ceiling using a thin thread to perform experimental tests and extract the modal parameters. Impact on orange samples was applied at three angles of 7° (below the yield point), 10° (dynamic yield point), and 20° (above the dynamic yield point).
Results and Discussion
To validate the experimental (laboratory) natural frequencies and simulation, the comparison between these frequencies showed that in large-group oranges, the first, second, and third modes have experimental natural frequencies of 125.4, 146.9, and 180.4 Hz, respectively. Also, the simulation frequencies (modal frequencies) are 133.80, 146.16, and 196.66 Hz. The lowest and the highest differences were observed in the second (0.5%) and third mode (9.01%), respectively. in small-group oranges, the first, second, and third modes have experimental natural frequencies of 152.2, 188.8, and 242.2 Hz, respectively, and simulation frequencies are 167.79, 187.50, and 248.30 Hz. the lowest and highest differences between experimental and simulation natural frequencies were observed in the second and first modes (i.e., 0.68% and 10.24%, respectively).
Conclusion
Although there are some limitations, it can be agreed that Computer Aided Engineering (CAE) applications are very useful in predicting natural frequencies and modes of vibration of round fruits such as oranges. Using the obtained frequencies, especially the resonance frequency and the vibrational mode shape, In the actual transportation of orange, it is possible to avoid the resonance frequency by using appropriate packaging and transportation methods, so as to reduce the decay of fruit quality and predict the shelf life.
Research Article
Agricultural systems engineering (greenhouse, fish farming, mushroom production)
Zh. Seifi laleh; H. Samimi Akhijahani; P. Salami
Abstract
Introduction
With increasing the world's population, the need to supply water resources is increasing, as well. However, fresh water resources are out of reach due to climate changes, and production of drinkable water from seas and oceans has always been the focus of researchers. Iran with considerable ...
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Introduction
With increasing the world's population, the need to supply water resources is increasing, as well. However, fresh water resources are out of reach due to climate changes, and production of drinkable water from seas and oceans has always been the focus of researchers. Iran with considerable levels of solar radiation and the access to open water from the north and south is a suitable country to produce fresh water. Using solar water desalination systems is a proper and economical solution to produce drinking water from salt water sources. The purpose of this research is to increase the performance of the solar water desalination system by using the latent heat storage system and the solar tracking system. Water as working fluid and parabolic collector as a source of thermal energy were used experimentally to produce fresh water.
Materials and Methods
The solar water desalination system was designed and built on a laboratory scale in the University of Kurdistan and the desired experiments were performed on it. The flowing fluid (water) inside the spiral tube in the tank is entered into the absorber tube of the parabolic collector by means of a pump. As mentioned, inside the receiver tube, there is a spiral copper tube with a pitch of 7 cm, which contains paraffin. The parabolic mirror, reflects the sunlight on the receiver tube and causes the water (as working fluid) to heat up. The cooling process is done using a specific source placed in the upper part of the distillation tank. In this case, the steam droplets in the tank hit the bottom surface of this cooling tank (which is in the form of an inverted funnel) and condensation takes place. This research was carried out during four separate tests on 4 consecutive days of 24th, 25th, 26th, and 27th of August, 2022 for three volume flow rates of fluid 1.9, 3.1 and 4.2 l/min and without phase change materials in Renewable Energy Laboratory, university of Kurdistan, Sanandaj. The experiments were conducted under similar conditions and started at 10:00 and ended at 14:00. It should be noted that in the case without phase changing materials, the volume flow rate of the fluid was considered to be 4.2 l/min. In this case, the pump was transferring the fluid at its maximum flow rate. Variations of outlet temperature, thermal efficiency, desalination efficiency and produced water was investigated at different conditions.
Results and Discussion
The results showed that by reducing the pitch of the spiral tube, the amount of heat obtained increases due to the increase in the Nusselt number. At the beginning of data collection, a significant part of the energy entered into the receiver tube is used to heat the phase change material and the spiral tube inside the receiver and this reduces the initial air temperature. The highest salt water temperature occurs for the fluid flow rate with a flow rate of 4.2 l.min-1 and the lowest temperature occurs for a flow rate of 1.9 l.min-1. With a flow rate of 4.2 l.min-1, the heat absorbed by the absorbent tube is quickly transferred to the salt water chamber by the fluid. The input energy to the tank changes from 1.53 to 2.83, 1.14 to 2.18, and 0.73 to 1.48 MJ for fluid flow rates of 4.2, 3.1, and 1.9 l.min-1. For the system without phase change materials with a flow rate of 4.2 l.min-1, the thermal efficiency is lower than the cases with phase change materials (5.02 and 3.51 %). Moreover, using solar tracking mechanism, the thermal efficiency of the collector increased about 9.86% related to the system with photocell sensor. According to the values for water quality it can be stated that obtained sample water can be used for drinking by reducing the dissolved solids.
Conclusion
In this research, the process of thermal changes in the solar water desalination system using PCM has been investigated. The obtained results illustrated that using PCM improved the thermal efficiency of the collector. Moreover, the quality of obtained water from the present system was in acceptable range to drink. Using a solar panel tracking system improve the efficiency of the solar collector.
Research Article
Modeling
A. Shahraki; M. Khojastehpour; M. R. Golzarian; E. Azarpazhooh
Abstract
IntroductionDrying is one of the oldest methods of food preservation. In order to increase the efficiency of heat and mass transfer and maintain the quality of the product, the drying process must be scientifically and accurately investigated. It is possible to carry out experimental tests and trial ...
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IntroductionDrying is one of the oldest methods of food preservation. In order to increase the efficiency of heat and mass transfer and maintain the quality of the product, the drying process must be scientifically and accurately investigated. It is possible to carry out experimental tests and trial and error in the drying process by spending time, cost and consuming energy resources. If it is possible to use the available software with technological progress and by designing a general model for drying food in different initial conditions, it will be possible to optimize the drying process.Materials and MethodsThis study was conducted with the aim of simulating heat transfer and mass transfer during refractance window drying for aloe vera gel. With the use of Comsol Multiphysics version 5.6, a three-dimensional model was created to solve the heat transfer and mass transfer equations. For this purpose, the differential equations of heat and mass transfer were solved simultaneously and interdependently. The above model is considered with initial conditions, water temperature of 60, 70, 80 and 90 ◦C and aloe vera gel thickness of 5 and 10 mm. The initial humidity and temperature of aloe vera is uniform and its initial temperature is 4 ◦C, the initial humidity of fresh aloe vera samples is 110 gwater/gdry matter. Heat is supplied only by hot water from the bottom surface of the product.Results and DiscussionThe results showed that the drying time needed to reduce the moisture content of aloe vera gel from 110 to 0.1 gwater/gdry matter during refractance window drying at water temperature of 60, 70, 80 and 90 ◦C for 5 mm thick aloe vera gel was 120, 100, 70 and 50 minutes respectively and for 10 mm thick aloe vera gel was 240, 190, 150 and 120 minutes respectively. Also, the drying speed in hot water at 60, 70, 80 and 90 ◦C for 5 mm thick aloe vera gel was 0.915, 1.099, 1.57 and 2.198 gwater/min respectively. And for 10 mm thick aloe vera gel was 0.457, 0.578, 0.732 and 0.915 gwater/min respectively.ConclusionAccording to the simulation results, the best model is with a water temperature of 90 ◦C and a thickness of aloe vera gel of 5 mm. As a result, the modeling results are consistent with the results of experimental data.
Research Article
Bioenergy
M. Zarei; M. R. Bayati; M. A. Ebrahimi-Nik; B. Hejazi; A. Rohani
Abstract
IntroductionAnaerobic bacteria break down organic materials like animal manure, household trash, plant wastes, and sewage sludge during the anaerobic digestion process of biological materials to produce biogas. One of the main issues in using biogas is hydrogen sulfide (H2S), which, in concentrations ...
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IntroductionAnaerobic bacteria break down organic materials like animal manure, household trash, plant wastes, and sewage sludge during the anaerobic digestion process of biological materials to produce biogas. One of the main issues in using biogas is hydrogen sulfide (H2S), which, in concentrations between 50 and 10,000 ppm, can corrode pipelines and engines. One method for removing H2S from biogas that has minimal operating costs and investment requirements is biofiltration. Whether organic or inorganic, the biofilter's bed filling materials must adhere to certain standards, including having a high contact surface, high permeability, and high absorption. In this study, biochar and compost were used as the biofilter bed particles to study the removal of H2S from the biogas flow in the lab initially. Next, kinetic modeling was used to provide a numerical description of the removal process.
Material and Methods
To remove H2S from the biogas in this study, a biofilter was constructed on a lab size. As materials of the biofilter bed, biochar and compost were employed seperately. Due to its high absorption capacity and porosity, biochar becomes a good choice for substrate and packed bed in biofilters. The biochar was broken into 10 mm long, 5 mm wide, cylindrical pieces that were then used. Compost was also used as substrate particles in addition to biochar because it contains nutrients for microorganisms. Compost granules with average dimensions of 3 mm in diameter and 7.5 mm in length were used. As a biofilter reactor, these substrates were put inside a cylinder with a diameter of 6 cm and a height of 60 cm. The biofilter's bottom is where biogas enters, and its top is where it exits. Biogas was flowing at a rate of 72 liters per hour. Mathematical modeling was also used to conduct kinetic studies of the process in order to better comprehend and generalize the results. This method involves feeding the biofilter column with biogas that contains H2S while the biofilm is present on the surface of the biofilter bed particles. The bacteria in the biofilm change the gaseous H2S into the harmless substance sulfur and store it in their cells. These assumptions form the foundation of mathematical models. The H2S concentration is uniform throughout the gas flow, the gas flow is constant, and the column's temperature is the same at a specific height.
Results and Discussion
In the beginning, biochar was used as a substrate in the biofilter to test its effectiveness, and good results were obtained in removing H2S from the biogas. H2S concentration in biogas has been significantly reduced using biochar beds. It has dropped from 300 ppm and 200 ppm to 50 ppm in the state of greatest H2S concentration reduction. Methane levels in the biogas were not significantly impacted by the biofilter. This issue is regarded as a good and significant outcome when taking into account the goal of producing biogas, which has a high concentration of methane. The elimination effectiveness was 94% in the biochar bed at 185 ppm input H2S concentration. The removal efficiency also reached 76% in the compost bed and at an input concentration of 70 ppm. Using mathematical models, the simulation was carried out by modifying the model's parameters until the predicted results closely matched the actual experimental data. It may be concluded that the suggested mathematical model is sufficient for the quantitative description of H2S removal from biogas utilizing biofilm in light of how closely the calculation results matched the experimental data. The only model parameter that was changed to make the model results nearly identical to the experimental data was the value of the parameter μmax. Besides, μmax has the greatest influence on the model results. The value of μmax for the biochar bed was calculated as 0.0000650 s-1 and for the compost bed at 70 ppm and 35 ppm concentrations as 0.0000071 s-1 and 0.0000035 s-1, respectively.ConclusionThe primary objective of this study is to examine the removal of H2S from biogas using readily available and natural substrates. According to the findings, at a height of 60 cm, H2S concentration in biochar and compost beds decreased from 185 ppm to 11 ppm (removal efficiency: 94%) and from 70 ppm to 17 ppm (removal efficiency: 76%). The mathematical models that were created may quantify the H2S elimination process, and the μmax values in biochar and compost were calculated as 0.0000650 s-1 and 0.0000052 s-1, respectively.AcknowledgementThe authors would also like to thank UNESCO for providing some of the instruments used in this study under the grant number No. 18-419 RG, which was funded by the World Academy of Sciences (twas).
Research Article
Precision Farming
M. Naderi-Boldaji; M. Tohidi; M. Ghasemi-Varnamkhasti
Abstract
Evaluation of dielectric spectroscopy in fusion with Vis-SWNIR spectroscopy for measurement of sugar concentration on sugarcane stalk samplesIntroductionDevelopment of rapid instruments for measuring the quality attributes of sugarcane such as sugar concentration and water content is one of the important ...
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Evaluation of dielectric spectroscopy in fusion with Vis-SWNIR spectroscopy for measurement of sugar concentration on sugarcane stalk samplesIntroductionDevelopment of rapid instruments for measuring the quality attributes of sugarcane such as sugar concentration and water content is one of the important needs in agricultural and industrial technology of sugarcane production and processing. Near infrared (NIR) spectroscopy has been one of the techniques widely applied for quality evaluation of sugarcane. However, NIR spectrophotometers in the full NIR wavelength range (up to 2500 nm) are expensive devices which are not readily available for portable applications. Short-wave NIR devices in the range of 1100 nm are available with lower costs but need to be evaluated for any specific application. On the other hand, dielectric spectroscopy has attracted the attention of researchers for quality evaluation of agricultural and food products. In a previous study, a parallel-plate capacitance sensor was developed and evaluated for non-destructive measurement of sugarcane Brix (total soluble solids) and Pol (sucrose concentration) as well as water content in the frequency range of 0-10 MHz. The results showed excellent prediction models with root mean square errors smaller than 0.3 for Brix and Pol. This study was aimed at development and evaluation of a dielectric sensor to be extendable for portable measurements on standing sugarcane stalk in comparison with short-wave NIR (SWNIR) spectroscopy to address how the fusion of the two methods may improve the accuracy of models for prediction of sugarcane Brix. Materials and MethodsA dielectric senor in the form of a gadget was developed with metallic electrodes to encompass the sugarcane stalk samples. The dielectric sensor was excited with sinusoidal voltage within 0-150 MHz frequency by a function generator and the conductive power through the electrodes was measured with a spectrum analyzer. 105 sugarcane stalk samples were prepared from seven sugarcane varieties and scanned by the dielectric sensor. The samples were also subjected to Vis-SWNIR radiation in the wavelength range of 400-1100 nm and the reflectance spectra were captured. Reference Brix and water content of the samples were determined using a portable refractometer and oven-drying method, respectively. Regression analyses and artificial neural networks were performed on independent and combined data of dielectric and Vis-SWNIR spectroscopy to develop prediction models for Brix and water content. Results and discussionPartial least square regression on independent data sets of each instrument resulted in RMSEP= 1.14 and RMSEP= 1.88 for Brix using Vis-SWNIR and dielectric spectroscopy, respectively. Moreover, data fusion of dielectric and Vis-SWNIR spectroscopy in low level for prediction of Brix significantly improved the prediction accuracy to R2P= 0.94 and RMSEP= 0.74. The medium level data fusion resulted in R2P= 0.89 and RMSEP= 0.93 for prediction of water content.ConclusionIn this study, Vis-SWNIR spectroscopy and dielectric spectroscopy methods were evaluated for measurement of sugarcane Brix and water content on stalk samples. To develop prediction models for Brix and water content, partial least squares (PLS) regression and artificial neural network (ANN) were compared. First, the prediction models were developed based on independent measurement of Vis-SWNIR and dielectric spectroscopy and then the fusion of the two techniques to improve the prediction accuracy was investigated. With fusion of the two methods at an intermediate level, the RMSE of Brix was obtained to be 0.74 which is a noticeable improvement as compared with the other studies. Based on the results achieved, development of a fusion probe of SWNIR and dielectric spectroscopy and measuring system could be the aim of future studies for in-situ evaluation of standing sugarcane quality parameters. Regarding the importance of measuring the quality properties of sugarcane during growth and maturity, the results of this study can have a significant role in development of a combined portable measurement system of NIR and dielectric spectroscopy methods for fast and non-destructive indication of sugarcane quality parameters. AcknowledgementThis article was extracted from a research project financially supported by the research deputy of Shahrekord University. The Grant number was 0GRD34M1614. The authors would like to appreciate the support of the Amir-Kabir Sugarcane Agro-Industry Co., Khuzestan, Iran for providing the sugarcane stalk samples. Keywords: Dielectric spectroscopy, Visible-Near infrared spectroscopy, Data fusion, Brix, Sugarcane
Research Article
Modeling
S. Sharifi; N. Hafezi; M. H. Aghkhani
Abstract
IntroductionEfficient use of energy in paddy production prevents the destruction of agricultural ecosystems by reducing greenhouse gas emissions and causes the development and promotion of sustainable agriculture. Meanwhile, intelligence agriculture has come to the aid of farmers and policy-makers by ...
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IntroductionEfficient use of energy in paddy production prevents the destruction of agricultural ecosystems by reducing greenhouse gas emissions and causes the development and promotion of sustainable agriculture. Meanwhile, intelligence agriculture has come to the aid of farmers and policy-makers by using up-to-date knowledge, to lead to sustainable welfare and comfort of human society in the present and the future. Therefore, the purpose of this study was to investigate energy consumption and production, modeling and optimization of two paddy cultivars yield by Artificial Bee Colony (ABC) and genetic algorithm.Materials and MethodsResearch data were collected from studying documentary and library information and using face-to-face questionnaires with 120 (including 80 high-grading and 40 high-yielding) paddy farmers and farm owners in Rezvanshahr city in Guilan province during the production year 2019-2020. The independent variables were, machinery, diesel and Gasoline fuels, electricity, seed, compost and straw, biocides, fertilizers and labor, and the dependent variable was paddy yield per hectare of the farm area. In the first step, calculations of energy consumption and production were obtained by multiplying the amount of the variables by the relevant and equivalent coefficients.In the second step, all of the variables in order to maximize paddy yield are entered into MATLAB software. Therefore, the artificial bee colony algorithm with a novel and simple elitism structure was used for the fitness function in the genetic algorithm. The Sphere function, the Repmat function and the Unfrnd function were used as the objective function, defining position of the bee arrays and quantifying the position of the bee arrays, respectively. The number of new responses per each of the generations and algorithm iterations was 900 members and 200 iterations, respectively. Also, in the genetic algorithm, the population type and size were considered double vector and 100.Results and DiscussionThe results showed that total average energy consumption and production in the Hashemi (high-grading) paddy cultivar were obtained 55.973 and 30.742 GJ.ha-1, respectively, and in the Jamshidi (high-yielding) paddy cultivar were 54.796 and 62.522 GJ.ha-1, respectively. In both cultivars, the highest and lowest distributions of energy consumption were related to agricultural machinery and straw, respectively. The average energy consumption of tractor in the Hashemi and the Jamshidi cultivars were 25.111 and 25.865 GJ.ha-1, respectively, which were obtained 44.862 % and 47.202 % of total average energy consumption, respectively. Undoubtedly, it shows that inescapable effect of this input and refers to the operators' skill and experimental knowledge. The results of evaluation indexes such as R2, RMSE, MAPE and EF, and statistical comparison such as mean, STD and distribution indicated that the artificial bee colony algorithm had the essential condition for the fitness function. The optimization results of the bee-genetic algorithm demonstrated that most of the consumed resources are not a little difference from the optimum conditions but can be adopted the proper management in the farm, the Hashemi and the Jamshidi cultivars optimization of energy consumptionwill achieve 53.96 % and 39.41 %, respectively.ConclusionAccording to the results of the desirable performance of the ABC-GA algorithm and identifying the potential of saving energy consumption, policy-makers of the energy resource management and rice industry managers can define new strategies to reduce energy consumption.
Research Article
Modeling
M. Almaei; S. M. Nassiri; M. A. Nematollahi; D. Zare; M. Khorram
Abstract
Introduction
Drying shrimp is one of the storage methods that, while increasing the shelf life, leads to the production of a diverse product with different uses, from consumption as snacks to use as one of the main components of foods. Drying is preferred over other preservation methods due to advantages ...
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Introduction
Drying shrimp is one of the storage methods that, while increasing the shelf life, leads to the production of a diverse product with different uses, from consumption as snacks to use as one of the main components of foods. Drying is preferred over other preservation methods due to advantages such as long shelf life, microbial stability, easy consumption, reduced transportation costs, high added value, and product diversity.
In order to simulate all these processes and thus obtain information such as their shelf life as well as the energy required for the processes, it is necessary to determine the initial and final temperature of the product, its geometry and dimensions, as well as their thermo-physical characteristics. Simulation of different drying processes requires accurate estimation of effective moisture diffusion coefficient. This parameter is highly dependent on temperature and humidity, which level of dependence is usually shown by an equation with an Arrhenius structure as an empirical function of humidity and temperature, or by considering the activation energy.
It is necessary to have sufficient knowledge about heat and mass transfer characteristics, such as diffusion or penetration coefficient and heat transfer coefficient to estimate the final temperature and drying time. In this study, the drying process of peeled farmed shrimp (Litopenaeus vannamei) in a convective hot air dryer, and variations in related parameters such as shrinkage and effective moisture diffusion coefficient were studied.
Materials and Methods
A drying device was built to conduct experimental experiments on drying shrimp samples. Experiments were performed on samples of shrimp meat slices at temperatures of 40, 50 and 60 degrees Celsius and constant air velocity of 1.5 m/s. The basis of experimental drying models was on diffusion theory. In these models, it was assumed that the resistance to the diffusion of moisture occurs from the outer layer of food. In most cases, Fick's second law is used to describe the phenomenon of moisture penetration.
In the present study, the standard method of measuring volume changes by immersion method (in toluene) was used to determine the sample volume changes. During drying time, the volume of the samples were measured at intervals of 45 minutes, and their volume changes were calculated. To measure the moisture content of the samples, at the beginning of each test, the weight of the samples were recorded with a digital scale with an accuracy of ±0.001 g. Then, during drying time of the samples, simultaneously with the volume measurement, the samples were weighed.
The most common way to model shrinkage during the drying process is to obtain an empirical relationship between shrinkage and moisture, for which linear and non-linear models were used. In most cases, effective permeability is defined as a function of humidity and temperature. For this purpose, by using curve fitting methods on the data obtained from experimental tests and including the Arrhenius equation (for most food items), the appropriate function was extracted.
Results and discussion
With considering the results of statistical indices, the linear model was the best model for expressing shrinkage changes versus moisture ratio changes among the experimental models considered for shrinkage and drying kinetics, and Weibull distribution was the best model for expressing moisture ratio-time variations. A moisture dependent experimental model was used to express the changes in the apparent density of shrimp, by which the range of 1017-1117 kg/m3 was computed. Moreover, to express the effect of moisture content and temperature on the effective diffusion coefficient of shrimp, an Arrhenius equation was derived. According to the results, the variations in the effective diffusion coefficient of shrimp ranged between 0.08 ×10-9 m2/s to 7.39×10-9 m2/s. While deriving the effective diffusion coefficient, the influence of the number Fick's second law terms on moisture ratio variation was studied, and it was found that number of terms more than 100 could not change the model outputs, considerably.
Conclusion
Among the evaluated shrinkage models, a linear model with the highest coefficient of determination (R2) and the lowest root mean square error and sum of square error (SSE) was the best model for interpreting shrinkage at the tested temperature levels. The experimental model of Weibull distribution in the evaluated temperature range, was the most suitable model to express the changes in the moisture ratio of shrimp meat slices against time. Arrhenius model for predicting the effective diffusion coefficient of shrimp slices predicted the changes in the diffusion coefficient of shrimp meat slices with respect to temperature and moisture content in the evaluated temperature range.
Research Article
Design and Construction
M. Teimorzadeh; J. Baradaran Motie; A. Rohani; Y. Selahvarzi
Abstract
Introduction
The lack of giving attention to the water needs of trees can lead to water wastage or water stresses in trees. Accurate irrigation of trees requires the availability of information on the amount and manner of water consumed in trees. However, for the precise implementation of irrigation, ...
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Introduction
The lack of giving attention to the water needs of trees can lead to water wastage or water stresses in trees. Accurate irrigation of trees requires the availability of information on the amount and manner of water consumed in trees. However, for the precise implementation of irrigation, a reliable method of measuring the plant's water requirements is needed to avoid water stress. Existing methods of measuring the water requirement of trees can often be used for a part of the tree (such as stem or leaf) and require the presence of the user and spend time and money, so these methods are often used in research applications.
Materials and Methods
A sap-flow meter device was also developed to make a heat pulse in a tree trunk every 15 minutes. The device consists of measuring probes, a processor unit, and a data logger. In order to evaluate, the device the probes were installed on the trunk of the Ficus Benjamina tree in a controlled environment, at two different heights, and the results of the sap flow through the vascular tissue were compared with the data obtained by the lysimetric method. The Ficus Benjamina tree with a trunk diameter of 3.5 cm and height of 196 cm was prepared in the summer of 2022. By measuring the speed of destruction of the heat pulse and using the theorem of heat transfer, and assuming that heat transfer is done only through the sap flow from vascular tissue, the amount of sap flow was estimated by the Heat ratio method (HRM).
The trunk was triple drilled 1.5 mm in diameter and 25mm in depth. After drilling, the probes were placed in the holes. In order to avoid heat transfer from the probes to the outside, the trunk was covered by Glass wool insulation (Figure 3). To measure the reliability of the device, the lysimetric method was used to measure the tree transpiration. For this purpose, the soil surface of the pot was covered with cellophane so that the evaporation and weight reduction of the pot were done only from the leaves of the tree. Every hour, the weight of the pot was measured by a digital scale. Changes in the weight of the pot indicate the amount of water evaporated. In other words, this water has been transferred through the vascular tissue of the tree trunk.
Results and Discussion
The results showed that the sap-flow meter device measures the amount of water consumption of the tree with a little overestimation compared to the value obtained by the lysimetric method. Sap flow and transpiration follow a similar trend so that it increases during the day and reaches their peak value in the middle of the afternoon. This value reached 17.98 ml.h-1 for sap flow and 16 ml.h-1 for transpiration (by lysimetric method), followed by a rapid decrease in the late afternoon as the air was cooled. In addition, the results of device measurements showed spraying irrigation on the leaves lowers the speed and amount of sap flow. Water spraying on the leaves affects the speed of sap flow, so that when the canopy gets wet, water evaporation from the leaf surface made them colder, and the speed of sap flow decreases significantly.
The v1/v2 ratio is not constant with time, and selecting the appropriate measurement starting time is essential for the working cycle of the device for the data acquisition. It is essential to measure (by the device) the difference between temperature probes 40 seconds after heat pulse generation. The sap flow and transpiration followed a similar trend during the experiments, the sap flow and transpiration increased during the daytime and reached their peak value in the middle of the afternoon, which is 17.98 ( ) for the first day and 19.75 ( ) sap flow in the second day. The related lysimetric method transpirations reached 16 ( ), followed by a rapid decrease in the late afternoon.
Conclusion
According to the obtained results, the following are deduced from the developed device:
Sap flow and transpiration follows a similar trend during the test period, and the estimated value of the sap flow is 30 percent higher than that of the lysimetric method.
The device was able to show the effect of surface irrigation well, irrigation by spray affects the speed of sap flow so that when the canopy gets wet, the speed of sap flow decreases noticeably. Sap flow and transpiration are directly proportional to air temperature, and canopy temperature, and inversely proportional to relative humidity.
The results showed that the heat pulse method after calibration can reliably estimate the amount of sap flow in the vascular tissue of trees.
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