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
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
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-en
Modeling
S. Karimi Avargani; A. Maleki; Sh. Besharati; R. Ebrahimi
Abstract
The main objective of this paper is to develop a seven-link dynamic model for the operator’s body while working with a motorized backpack sprayer. This model, includes the coordinates of the sprayer relative to the body, the rotational inertia of sprayer, the muscle moments acting on the joints ...
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The main objective of this paper is to develop a seven-link dynamic model for the operator’s body while working with a motorized backpack sprayer. This model, includes the coordinates of the sprayer relative to the body, the rotational inertia of sprayer, the muscle moments acting on the joints and a kinematic coupling that keeps the body midway between the two legs. The constraint functions are determined and the non-linear differential equations of motion are derived using the Lagrange’s equations. The results show that, undesirable fluctuations in the ankle force are noticeable at the beginning and end of the swing phase. Therefore, injuries to the ankle joint due to vibrations are more likely. The effects of engine speed and sprayer mass on the hip and ankle joint forces are then investigated. It is found that, the engine speed and sprayer mass have significant effects on the hip and ankle forces and can be used as effective control parameters. The results of the analysis also show that increasing the engine speed increases the frequency of the hip joint force; however, no significant effects on the frequency of the ankle joint force were observed. The results of this study may provide researchers with insight into estimating the allowable working hours with the motorized backpack sprayers, prosthesis design and load calculations of hip implants in the future.
Research Article-en
Bioenergy
J. Rezaeifar; A. Rohani; M. A. Ebrahimi-Nik
Abstract
In the quest for enhanced anaerobic digestion (AD) performance and stability, iron-based additives as micro-nutrients and drinking water treatment sludge (DWTS) emerge as key players. This study investigates the kinetics of methane production during AD of dairy manure, incorporating varying concentrations ...
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In the quest for enhanced anaerobic digestion (AD) performance and stability, iron-based additives as micro-nutrients and drinking water treatment sludge (DWTS) emerge as key players. This study investigates the kinetics of methane production during AD of dairy manure, incorporating varying concentrations of Fe and Fe3O4 (10, 20, and 30 mg/L) and DWTS (6, 12, and 18 mg/L). Leveraging an extensive library of non-linear regression (NLR) models, 26 candidates were scrutinized, with 8 emerging as robust predictors for the entire methane production process. The Michaelis-Menten model stood out as the superior choice, unraveling the kinetics of dairy manure AD with the specified additives. Fascinatingly, the findings revealed that different levels of DWTS showcased the highest methane production, while Fe3O420 and Fe3O430 recorded the lowest levels. Notably, DWTS6 demonstrated approximately 34% and 42% higher methane production compared to Fe20 and Fe3O430, respectively, establishing it as the most effective treatment. Additionally, DWTS12 exhibited the highest maximum methane production rate, reaching an impressive 147.6 cc on the 6th day. Emphasizing the practical implications, this research underscores the applicability of the proposed model for analyzing other parameters and optimizing AD performance. By delving into the potential of iron-based additives and DWTS, this study opens doors to revolutionizing methane production from dairy manure and advancing sustainable waste management practices.
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
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.
Research Article
Nanotechnology (packaging films, biocomposites, solar cells)
N. Tajari; H. Sadrnia; F. Hosseini
Abstract
IntroductionPolylactic acid is a biodegradable polymer that can replace petroleum-based materials in packaging films due to its unique properties. However, sometimes the degradability of polymers can be considered a negative factor, such as when big changes in the mechanical properties of the polymer ...
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IntroductionPolylactic acid is a biodegradable polymer that can replace petroleum-based materials in packaging films due to its unique properties. However, sometimes the degradability of polymers can be considered a negative factor, such as when big changes in the mechanical properties of the polymer occur during use. Another notable issue is the fragility of polylactic acid, which can be modified to some extent by adding some materials. Addition of materials such as nanoparticles and plasticizers can improve the flexibility or mechanical properties of polymer films. Polymer films for use in the packaging industry must have acceptable physical, mechanical, thermal, etc. characteristics. The acceptable level of these properties can be obtained by comparing with the standard values that exist for common polymers in this industry. Low density polyethylene is a common polymer in the packaging industry that can be a good benchmark for comparison. Mechanical properties, light absorption, contact angle and microstructures are some of the factors affecting the quality of the production film that were studied in this research. Investigating the mechanical properties of films produced from PLA is particularly important due to the degradability of this polymer over time. Polylactic acid films with different compounds containing PEG 400 and Tween 80 as plasticizers and ZnO nanoparticles were investigated for 14 months (in the first, second, third, fourth, and fourteenth months) in terms of mechanical properties. Finally, the obtained values were compared with standard values for packaging and their mechanical behavior was analyzed.Materials and MethodsExperiments were performed in post-harvest and central laboratories of Ferdowsi University of Mashhad. The films were prepared using the solvent casting method. First, PLA granules were dried for 24 hours at 60 ° C and then 1 g of PLA in 50 ml of dichloromethane was dissolved at room temperature by magnetic stirring for 12 hours. ZnO nanoparticles, PEG 400 and Tween 80 were incorporated into PLA and DCM solution, 1 wt% PLA, 20 wt% PLA and 0.25 wt% solution respectively. To prepare films containing nanoparticles, nanoparticles and dichloromethane were sonicated with an ultrasonic probe for 10 minutes and then added to the base solution and stirred for one hour. Mechanical properties of the samples were determined within 14 months based on the ASTM D882-02 standard method. A texture analyzer (H5 KS, Manchester, U.K.) was used for this test. Light absorption was studied using a spectrophotometer (CAMSPECM550, UK). Contact angle of the samples was measured with a goniometer (model 200-00, Ramé-Hart Instrument Co, Succasunna, USA) and according to the ASTM D5946-04 standard. The surface morphology of the samples was visualized by scanning electron microscope (LMU TESCAN BRNO-Mira3, Czech Republic. The results were analyzed using Minitab software version 18 (Minitab Inc, USA). The graphs were drawn in Microsoft Excel 2013.Results and DiscussionThe neat PLA film has a smooth surface, and with the addition of nanoparticles or plasticizers, the surfaces become uneven. The addition of nanoparticles and plasticizers caused more opacity of the film and better protection against ultraviolet rays. The presence of plasticizers, especially Tween 80, increased the hydrophilicity of the films. Packaging films should have ductile behavior, adding plasticizers caused ductile behavior, although Tween 80 was not able to create stable ductile behavior. The values of tensile strength, elastic modulus and elongation at break for low density polyethylene were reported as 11.7 MPa, 260.4 MPa and 225%, respectively. The lowest value of tensile strength (18.56 MPa) and elastic modulus (1114.68 MPa) were related to P400/T80. This difference shows the acceptability of polylactic acid in the packaging industry. The elongation value is much lower than the standard, which shows the need to modify this parameter.ConclusionThe results of this research showed the significant effect of film type on mechanical properties and the significant effect of storage time on tensile strength and elongation at break. The effect of various factors such as changes in the texture of the film due to the presence of plasticizers or non-uniform distribution of nanoparticles makes it impossible to determine a constant trend for the effect of time on the films. The elongation at break for the produced films was much lower than the standard, which still needs to be modified due to the importance and sensitivity of this parameter in packaging. Polylactic acid has high tensile strength and high elastic modulus, so it can be combined with different plasticizers with a higher percentage, other polymers or nanoparticles to improve flexibility. The stress-strain diagram confirms the presence of ductile behavior in most of the samples during 14 months, except for the neat PLA film and the film containing Tween 80 and nanoparticles. The presence of plasticizers and nanoparticles in the film substrate increased opacity and protection against ultraviolet rays. The produced films were more hydrophilic compared to low density polyethylene.
Research Article
Agricultural waste management
F. Mortazavi; R. Khodabakhshian; M. Moeenfard
Abstract
A group of phenolic compounds called tannins can be identified in terms of biological activity and chemical reactivity, which are used in leather, glue, dye, pharmaceutical and other industries. The extraction methods of these compounds are very diverse and extraction with acetone, ethanol, methanol ...
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A group of phenolic compounds called tannins can be identified in terms of biological activity and chemical reactivity, which are used in leather, glue, dye, pharmaceutical and other industries. The extraction methods of these compounds are very diverse and extraction with acetone, ethanol, methanol and water solvents have been the most tested. Ultrasonic extraction is an effective method for extracting chemical compounds that is performed in a shorter period of time compared to other methods and can be used for heat-sensitive compounds, including phenolic compounds. Potato is an annual vegetable and a very important agricultural product that has nutritional and industrial applications. The amount of phenolic compounds in potatoes is estimated to be between 5 and 30 percent of dry weight. In this research, the extraction of phenolic compounds, tannin and condensed tannin by ultrasonic method from potato peel was investigated and the effect of extraction time and type of solvent on the extraction rate of these compounds was investigated. To determine the amount of phenolic compounds, Folin Ciocalteo's reagent was used, polyvinyl polypyrrolidone was used to determine the amount of tannin, and acetone was used to determine the dense tannin. With the increase of extraction time, the amount of extracted phenolic compounds and total tannin increases, but the amount of extracted dense tannin does not depend on the extraction time. The lowest extraction related to ethanol solvent (13.6±22.6 mg per hundred grams of skin) during 10 minutes and the highest extraction was obtained from water solvent (8±9.50 mg per hundred grams of skin) /142) took 15 minutes in the extraction time.
Research Article
Agricultural systems engineering (greenhouse, fish farming, mushroom production)
M. Zangeneh; N. Banaeian
Abstract
IntroductionAgricultural mechanization is a crucial factor in driving agricultural development and is considered one of the most capital-intensive inputs in the agricultural sector. Effective management of the supply chain for agricultural mechanization is a crucial prerequisite for enhancing the quality ...
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IntroductionAgricultural mechanization is a crucial factor in driving agricultural development and is considered one of the most capital-intensive inputs in the agricultural sector. Effective management of the supply chain for agricultural mechanization is a crucial prerequisite for enhancing the quality of agricultural machinery and reducing operational expenses. This is imperative for the advancement of agricultural mechanization. The current research aimed to identify the primary structures of the supply chain for rice agricultural machinery in the Guilan and Mazandaran provinces. The study also examined the critical functional aspects of the chain members, which included manufacturers, importers, and retailers, as well as farmers who were the ultimate consumers of the chain's products. Additionally, the research investigated the processes that governed the supply chain.Material and MethodsThe measurement of supply chain performance involved the utilization of five distinct dimensions, namely cost, responsiveness, flexibility, asset, and reliability. The data collected in this study were analyzed utilizing the SPSS software. Furthermore, latent variables were generated at each level of the hierarchy by utilizing the variables from the aforementioned model. The normality of the variables was assessed using the Kolmogorov-Smirnov test. The evaluation of normal variables was conducted through a one-sample t-test, while the evaluation of abnormal variables was performed using a one-sample Wilcoxon test.Results and discussionThe Wilcoxon test results and the variables of commitment, cost management, and communication in the average test value. The variables of normal distribution, namely human resource management, quality management, strategic organization, flexibility, responsiveness, performance, and reliability in stores have a significant deviation from the mean value in stores. A descriptive analysis of manufacturers' and importers' expectations and limitations regarding rice machines was conducted.ConclusionsThe continuous demand for rice agricultural machinery in Iran has resulted in the bullwhip effect phenomenon being perceived as a less significant challenge in the supply chain. The majority of store managers and agricultural rice machinery dealers lack formal education in the field of agricultural machinery. The inclusion of individuals with educational backgrounds in agricultural machinery at various stages of the supply chain is likely to enhance the dissemination of information throughout the chain. Employing dependable techniques for transmitting accurate information regarding consumers' quality requirements can assist suppliers in manufacturing or importing superior-quality machinery. This approach not only minimizes uncertainty in the supply chain and streamlines inventory management but also reduces the lead time for meeting consumers' demands. At present, manufacturing enterprises possess comparatively limited knowledge regarding the market and technical requirements of rice farmers in comparison to their imported counterparts. It is advisable for manufacturing companies to broaden their comprehension of consumer requirements by diversifying their market evaluation techniques.
Research Article
Modeling
A. Taheri hajivand; K. Shirini; S. Samadi Gharehveran
Abstract
Scheduling projects in agriculture include operations and activities that are carried out in a certain order and within a certain period of time. If these operations and activities are not carried out on time, due to the quantitative and qualitative drop of the product, they will cause an increase in ...
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Scheduling projects in agriculture include operations and activities that are carried out in a certain order and within a certain period of time. If these operations and activities are not carried out on time, due to the quantitative and qualitative drop of the product, they will cause an increase in the costs of the agricultural unit, and as a result, they will cause untimely costs. Timely execution of agricultural mechanization operations and projects is one of the most important issues that have been considered in recent years. These costs will increase more if there are limited resources. In order to reduce the mentioned costs, these projects can be planned, scheduled and managed like industrial projects. To solve the project scheduling problem with limited resources, various methods have been presented, each of which tries to find the optimal solution. Considering that these problems are of NP-hard type, in this research, the colonial competition algorithm was used in order to schedule agricultural mechanization projects of two dominant products of Moghan agriculture and industry. The main goal of this schedule is to minimize the project completion time and reduce costs in such a way that there is no disruption in the timely implementation of agricultural operations. The information related to the activities, the resources required for each activity and the prerequisites for the activities of each product, and the parameters of the proposed algorithm have been implemented in MATLAB software and the results of the algorithm implementation show the success of the algorithm in Scheduling and optimal allocation of resources to each of the activities.
Research Article
Post-harvest technologies
E. Barzanouni; H. Sadrnia; F. Sohbatzadeh; S. Khodavaisy
Abstract
Penicillium digitatum is the main problem in citrus fruits during storage. In this study, the effect of cold atmospheric pressure plasma generated by a DC-driven self-pulsing transient spark discharge in a closed reactor was investigated on a suspension of Penicillium digitatum spores with different ...
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Penicillium digitatum is the main problem in citrus fruits during storage. In this study, the effect of cold atmospheric pressure plasma generated by a DC-driven self-pulsing transient spark discharge in a closed reactor was investigated on a suspension of Penicillium digitatum spores with different initial concentrations of H2O2 solutions (0, 0.05, 0.1, and 0.5 %) and in different plasma exposure times (2.5, 5, 10 and 15 min). Results showed that by increasing exposure time as well as the concentration of H2O2, the effect of inactivation increased. For 0.1 and 0.5% H2O2 solutions a complete inactivation of PD spores in 15 min was observed. The atmospheric pressure plasma assisted to more oxidation of H2O2 solution that resulting in more cell deaths of the PD. In addition, the use of plasma allows to avoid using of high concentration solutions of H2O2 when washing fruits and vegetables to maintain their post-harvest properties in industrial scale.
Research Article
Modeling
M. Sadeghi-Delooee; R. Alimardani; H. Mousazadeh
Abstract
IntroductionThere are two types of hydropower harvesting methods, conventional and unconventional. In the conventional form of hydropower, the potential energy of water is harvested using a dam or barrage. However, in the unconventional form, the kinetic energy of flowing water is extracted using hydrokinetic ...
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IntroductionThere are two types of hydropower harvesting methods, conventional and unconventional. In the conventional form of hydropower, the potential energy of water is harvested using a dam or barrage. However, in the unconventional form, the kinetic energy of flowing water is extracted using hydrokinetic turbines. Resource assessment is a pivotal step in developing hydrokinetic energy sites. Power density (power per unit area) is used to estimate the theoretical hydrokinetic power of a site. Flow velocity and cross section area are the two variables that constitute the power density. Researchers conduct resource assessments via various methods such as numerical simulation, direct measurement of velocity or indirect velocity calculation using the discharge data. In the latter method, the Manning’s equation is used to convert the discharge data into velocity values. Although this method is straightforward for canals (with a fixed and known geometry), it is cumbersome to compute the hydraulic radius in rivers. To overcome this difficulty various researchers suggested using hydraulic geometry (HG) to estimate the width and depth of a river reach and compute the hydraulic radius based on these estimated values. The main objective of this study is to present and implement a fast method for hydrokinetic theoretical power assessment using HG and Manning’s equation.Materials and MethodsIn the present study two hydrometry stations (Gachsar and Siera-Karaj) were selected in the Karaj dam watershed to implement the resource assessment based on HG. A computer code including 4 steps was developed in Python using the Google COLAB environment.1. (Data Preparation): The monthly-averaged discharge, Manning’s roughness coefficient and slope were collected and imported to the code. The roughness coefficient could be determined directly or indirectly. In the present study it was considered to be 0.045 for the Karaj River according to the literature review. ArcGIS software and Digital Elevation Model (DEM) was used to extract the local slope of each hydrometry station. For this purpose, at first, the streams network of Alborz province was extracted, then the longitudinal elevation profile was measured using the 3D Analyst tools. 2. (Discharge Data Processing): Flow duration curve (FDC) is one of the computational tools used by engineers to describe the hydrological regime of watersheds. FDC is a graphical representation of cumulative distribution of flows. In the present study, all-time-of-record FDC for each station was constructed and 5 different probability distribution functions (PDF) were fitted on them. The results of PDF fittings were evaluated by different goodness-of-fit indices and the best PDF was selected.3. (Calculations of HG and Manning’s Equation): The reconstructed FDC from the previous step is used here to calculate the width and depth of flow using the HG formulas. These values along with the roughness coefficient and slope are used to calculate flow velocity using the Manning’s equation. Afterwards, having flow velocity values, power density is easily computed.4. (Generating Outputs): In the final step, 2 categories of outputs are generated: (1) duration curves (width, depth, flow velocity, and power density), (2) energy diagrams (theoretical and turbine extracted).Results and DiscussionThe goodness-of-fit indices of PDF fitting showed that the Lognormal PDF is the most suitable distribution to describe the FDC with a 0.99 coefficient of determination. The average discharge (Q50) for Gachsar and Siera stations were calculated to be 2.34 and 7.68 m3s-1 which is in agreement with previous studies. Results of the Manning’s equation calculations revealed that the flow velocity is not significantly different in these stations (8 % higher in Siera). Literature review suggests that axial flow (propeller) turbines are not suitable for installation in rivers since the have to be fully immersed and require at least 1 m depth. However, the base flow depth in Gachsar and Siera stations are less than this limit. Therefor the use of wide and short turbines such as Savonius turbines is suggested in the Karaj River. The energy analysis results show that the maximum monthly theoretical energy at Gachsar and Siera equal to 38500 and 125500 kWh respectively. However, considering a turbine with 1 m2 swept area and a power coefficient of 0.2, the maximum monthly extracted energy will reduce to 940 and 1142 kWh at these two stations.ConclusionIn this study a fast method for hydrokinetic theoretical power assessment was presented and implemented on two hydrometry stations in the Karaj dam watershed. The results of HG calculations revealed that the base velocity (V90) of 1.34 and 1.49 ms-1 is present at Gachsar and Siera stations respectively. According to the available depths at these stations it is suggested to use wide and short turbines such as Savonius turbines. It is estimated that the maximum monthly energy extracted by each single Savonius turbine with unit swept area at Gachsar and Siera reach 940 and 1142 kWh respectively.
Research Article
Agricultural systems engineering (greenhouse, fish farming, mushroom production)
L. Behrooznia; M. Khojastehpour; H. Hosseinzadeh-Bandbafha
Abstract
IntroductionPomegranate has gained global popularity due to its high vitamin content and antioxidant properties, attracting fans worldwide. The processing of pomegranate into various products, including pomegranate juice, has become a thriving industry. However, this processing requires significant energy ...
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IntroductionPomegranate has gained global popularity due to its high vitamin content and antioxidant properties, attracting fans worldwide. The processing of pomegranate into various products, including pomegranate juice, has become a thriving industry. However, this processing requires significant energy and chemicals, most of which are derived from fossil fuels. The combustion of these fuels releases harmful gases, contributing to global warming, environmental damage, and health risks. Unfortunately, the costs associated with these environmental burdens are often overlooked, neglecting the principles of environmental sustainability. Therefore, it is crucial to evaluate the monetary value of the environmental impacts throughout the life cycle of pomegranate juice production. This research aims to investigate the costs imposed on society, including the social costs of carbon emissions, the damage costs of air pollution, and the environmental prevention costs associated with processing pomegranate juice.Materials and MethodsThis study focuses on assessing the environmental impact costs generated during the processing of pomegranate juice in Mashhad city, Iran, from 2022 to 2023. The case study considered in this research is the Saman Bazar Razavi Co. To conduct an environmental impact cost assessment, the study first evaluates the environmental impacts released during the pomegranate juice production process using the life cycle assessment approach. The costs associated with these impacts are then estimated by multiplying the impact amounts with predetermined monetary coefficients. The study adopts a system boundary from fruit entry into the factory to the exit of packaged juice, with a functional unit defined as a 160g pack of pomegranate juice. SimaPro software, version 9, is utilized for analyzing the environmental impacts. The evaluation of environmental impact costs encompasses three categories: social costs of carbon emissions, damage costs of air pollution, and environmental prevention costs. Carbon dioxide emissions are considered to assess social costs, while five gases—nitrogen oxides, particulate matter, sulfur dioxide, volatile organic compounds, and ammonia vapor—are considered for investigating air pollution damage costs. Additionally, seven impact categories—global warming, photochemical oxidation, respiratory inorganics, human toxicity, ecotoxicity, eutrophication, and acidification—are taken into account to calculate environmental prevention costs.Results and DiscussionThe investigation reveals that the production of pomegranate juice emits approximately 0.12 kg CO2 eq of carbon, with a social cost of $0.0062 per functional unit. The primary contributors to carbon emissions are natural gas and electricity. Furthermore, the evaluation of air-polluting gases indicates a total cost of $0.021 for air pollution damage. Among the five considered gases, ammonia vapor, sulfur dioxide, and nitrogen oxides incur the highest damage costs. The assessment of environmental prevention costs demonstrates a total calculated cost of $0.026, with global warming and acidification impact categories having the largest contributions of 59% and 28% respectively. This finding suggests that the majority of prevention costs associated with pomegranate juice production should be directed towards mitigating damage caused by global warming. Notably, the consumption of natural gas and electricity during the pomegranate juice production process is the main source of carbon dioxide emissions and global warming. Additionally, in terms of acidification, the contributions of pomegranate, electricity, apple, natural gas, and sugar are noteworthy.In line with these findings, it is evident that the resources derived from fossil fuels, which are consumed in pomegranate juice processing, have the most significant impact on environmental damage. Therefore, one practical method to prevent the creation of these pollutants is the utilization of alternative bio-products produced from biomass. Considering the substantial amount of pomegranate waste generated after juice processing, which is often not utilized, these wastes can be effectively employed to produce bioenergy, such as biogas. This approach not only prevents waste disposal but also offers economic and environmental benefits.ConclusionThis article provides an overview of the environmental impacts and associated costs of pomegranate juice production in Mashhad. Using the life cycle assessment approach, the study calculates the environmental impacts per functional unit (a 160g juice pack) and estimates the corresponding costs. The results indicate that the social costs of carbon emissions, total damage costs of air pollution, and total environmental prevention costs per functional unit are $0.0062, $0.021, and $0.026, respectively. These costs should be allocated to mitigating the environmental damage caused by pomegranate juice production in the region.
Research Article-en
Gh. Bahrami; M. H. Aghkhani; M. R. Golzarian; B. Deiminiat
Abstract
The present study investigated the use of the cyclic voltammetric electrochemical method and the electronic tongue (e-tongue) method for detecting of adulteration in lime juice. Since the measurement of the citric acid content in lime juice is an accepted indicator of the adulteration of lime juice in ...
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The present study investigated the use of the cyclic voltammetric electrochemical method and the electronic tongue (e-tongue) method for detecting of adulteration in lime juice. Since the measurement of the citric acid content in lime juice is an accepted indicator of the adulteration of lime juice in laboratories, it was first tried to determine its concentration using a potentiostat device and the cyclic voltammetry method for which various electrodes including glassy carbon, graphite, gold, and carbon nanotube and gold nanoparticle-modified glassy carbon electrodes, were used. Different conditions were considered by testing citric acid at multiple concentrations in buffers with different pHs. The results showed that the electrochemical behavior of citric acid was weak, so conventional electrochemical methods could not be used to check its behavior. The second part, evaluated a portable electronic tongue system (e-tongue). Eight samples of adulteration levels (from 5% up to 95%) were created in lemon juice (0, 5, 10, 20, 40, 70, 95, and 100% impurity). Unsupervised models including Principal Component Analysis (PCA) and Hierarchical Clustering Analysis (HCA) and supervised models, including Multilayer Perceptron (MLP) neural networks and Support Vector Machine (SVM) were used. Based on the results, the PCA fingerprint showed good discrimination between adulteration levels. HCA further confirmed this. The results of the analysis of supervised methods showed that the MLP model outperformed the SVM model in predicting fraud levels with a success rate of 99.33% and high correlation coefficients (R2=0.9973 and the RMSE= 0.09). These results show that the proposed system can separate different levels of adulteration in lemon juice and can be used as a taste quality control system.
Research Article-en
Image Processing
O. Doosti Irani; M. H. Aghkhani; M. R. Golzarian
Abstract
Robotic harvesting of agricultural products is an important and effective process for producing healthy fruit, reducing harvesting costs, and increasing productivity. Machine vision is evolving to use three-dimensional information instead of two-dimensional information. However, harvesting sweet peppers, ...
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Robotic harvesting of agricultural products is an important and effective process for producing healthy fruit, reducing harvesting costs, and increasing productivity. Machine vision is evolving to use three-dimensional information instead of two-dimensional information. However, harvesting sweet peppers, one of the greenhouse products, faces challenges due to the low precision of two-dimensional sensors. This study aims to develop an unsupervised machine vision algorithm to recognize colored sweet peppers using a combination of geometric features (fast point feature histogram - FPFH) and color features (HSV). Depth images were obtained using the Kinect-v2 sensor, and the 3D model was reconstructed. After extracting geometric and color features, the data was preprocessed by balancing it using the undersampling method and filtering outliers employing the Z-score criterion. Principal component analysis (PCA) was used to reduce the feature dimensions, and the k-means clustering model was applied to cluster the data using six geometric features and three color features. The silhouette coefficient was used to evaluate the clustering quality, and human evaluation showed that the algorithm achieved a 95.10% detection accuracy for sweet peppers.