Journal of Agricultural Machinery

Abstract Introduction
Peanut (Arachis hypogaea L.) is an annual plant of the legume genus that is cultivated in 109 countries due to its high-quality oil and seed protein. In Iran, this crop is cultivated on an area of 3000 hectares, with an average yield of 4 tons per hectare. Threshing performance significantly affects seed loss and physical damage, including cracking and crushing of seeds during harvest. Therefore, over the last century, extensive research has been conducted on different types of threshing methods, as well as the design and development of various threshing machines.
Research on seed crops such as cereals and seeds suggest that factors such as the rotational speed of the thresher, threshing-concave distance, feeding rate, and shape of threshing teeth play a crucial role in determining the threshing efficiency and quality of the threshed seeds. Although limited research has been conducted on peanut threshing, there are currently no combine-machines available for this crop on global markets. Therefore, this study aims to investigate several working parameters of an experimental peanut thresher, including the effect of sieve angle, sieve range of movement, and suction speed on the separation unit.
Materials and Methods
The relevant experiments were conducted in the Parsabad Moghan region of Ardabil province (latitude 39.65 North, longitude 47.91 East). To conduct the experiments and separate the seeds from the pods, we used a peanut threshing machine cultivar Nc2, which is commonly cultivated under agricultural conditions in Ardabil and Gilan Agricultural Research Centers.
To achieve the aims of this research, we investigated several effective parameters in the performance of the machine, including sieve angle, sieve movement range, and fan suction speed, to obtain the best settings for maximum threshing performance and separation efficiency. It is worth noting that the average seed weight per kilogram of peanut plant was between 300-400 grams, and the moisture content of the seeds in the tested cultivar was 45%. Before using the machine, workers must first dig up the plants and place them on the ground in a coupe, after which another worker must feed the plants into the machine through the feeder.
Results and Discussion
The study found that changes in sieve angle, sieve movement range, and suction speed significantly affect the separation efficiency and peanut loss rate at a 1% significance level. Increasing the sieving angle leads to a higher speed of material movement on the sieve, which results in insufficient time for separating straw from the seed. Similarly, increasing the sieve movement range causes a rapid decrease in cleaning efficiency. To achieve better straw-seed separation, it is necessary to apply impact shocks to the products located on the sieve within a short period. However, as the range of movement increases, the time interval between impact shocks also increases, which disrupts the straw's separation from the seed.
The study found that increasing the sieve range and suction speed leads to a higher rate of peanut loss. This is due to the fact that when the suction speed and sieve movement range are increased, the product spends less time on the sieve, which results in insufficient time for proper separation. Additionally, high speed may exceed the limit of peanut seed and cause it to move out of the machine with the straw. Increasing the sieve movement range leads to a more uniform movement of straw and seed on the sieve; however, achieving better separation of straw from the sieve requires dynamic shocks and sudden acceleration, which decreases as the sieve movement range increases. The optimal farm capacity and material capacity were achieved with a 5-degree slope at 0.55 hectares per hour and 509 kilograms per hectare, respectively, using a sieve range of 3.5 centimeters and a fan suction speed of 8 meters per second.
Conclusion
The study concluded that the sieve movement range has the most significant impact on cleaning efficiency, while the sieve angle has the least effect. Similarly, the sieve movement range has the most significant influence on the rate of peanut loss, while the sieve angle has the least effect.

Abstract Introduction
Various methods have been performed to control weeds in the world and the use of herbicides is one of them, but public concerns about human health have changed interest in alternative methods. Thermal methods based on flame-weeder, hot air, steam, and hot water have the potential to control weeds, but due to the high cost are not economical. Electromagnetic waves transfer energy into weeds and finally destroy them. The effect of radiation on plant mutation, high consumption of energy, and human health are problems for this approach. Unlike other methods, electrical energy is an ideal and non-chemical method for weeds. This method applies high voltage to weeds, their roots, and soil so that electric currents pass through them, and the vaporization of the liquid content of weeds kills the weeds. To increase the severity of damage to weeds, the development of a feedback mechanism is required. The ultrasonic sensor measuring physical parameters like plant height is a simple method. Some complex sensing systems include optical sensors such as infrared, and machine vision that require high-speed processors and expensive equipment. In this project, as a simple method, the monitoring of the electrical current passing through weeds was used for developing the feedback mechanism and increasing electric damage to weeds.
Materials and Methods
In this study, the system consisted of a high-voltage device that generated a 15 kV AC voltage to kill weeds, as well as a feedback mechanism that included a sensor to measure the electric current on the input of the weed killer and identify the presence of weeds and their annihilation. All parts were installed on a robotic platform, and an application on a laptop was connected to it via an access point for navigation and data reception. The system was tested in a greenhouse lab with various weeds. Initially, a test was performed to investigate the effect of high voltage on the weeds and establish relationships between the electric currents passing through weeds and their presence (before and after annihilation). During the test, the system was guided along a path and applied high voltage to kill the weeds. The feedback mechanism was then calibrated based on the extracted data on electric current relations. This allowed the system to detect weeds and their annihilation, enabling it to move to the next target once a weed had been eliminated. After calibration, a comparative test was conducted to evaluate the weed-killing efficiency of the two methods (with and without the feedback mechanism), and the results were analyzed using a t-test with p ≤ 0.01.
Results and Discussion
The observations indicated that the input electric current on the weed killer was dependent on the electric current passing through weeds. When the high-voltage electrode touched a weed, the electric current passed through it increased, and simultaneously, the high electrical energy destroyed the weed. After the removal of the weed, the electric current rapidly decreased. The average energy consumption per weed plant was estimated to be 250 joules, which can be compared with other methods. The final test comparing the use and non-use of the feedback mechanism revealed significant differences (P < 0.01) between the results obtained with and without the mechanism, demonstrating that the feedback mechanism increased the efficiency of weed annihilation. The sensing system used in the developed feedback mechanism is a simple method that is affected by the electrical resistivity of weeds. As such, it did not mistakenly detect other objects as weeds, unlike an ultrasonic mechanism. Based on these results, monitoring the electrical current passing through weeds proved to be a suitable method for developing a feedback mechanism for the weed killer to identify the presence of weeds and their annihilation.
Conclusion
The use of high voltage as a non-chemical and alternative method for weed control has shown promising results. The study revealed that measuring the electric current applied to the weed killer was an effective and straightforward approach to developing a feedback mechanism. This mechanism aids in identifying the presence of weeds and ensuring their elimination by intensifying the damage inflicted on them through the application of high electrical energy. To further enhance the efficiency and speed of weed control, future research should consider integrating an automatic guidance mechanism with the weed killer.

Abstract Introduction
The harvesting stage is the most crucial phase in peanut production. In other words, one of the critical stages in producing this product is the harvest stage. Although it has its difficulties, this stage is associated with significant losses, which experts attribute to the high economic value of peanuts. In recent years, farmers in the Moghan Plain have also started considering this product due to the special conditions of the Iranian economy. In 2020, this study investigated three methods of peanut harvesting in two stages: manual, tractor-mounted thresher (semi-mechanized), and harvesting with a pull-type combine. The first stage involves the complete removal of the plants from the soil, while the second stage involves drying and separating the peanut pod from the plant in Moghan.
Methods and Materials
The experiment followed a split-plot design in the form of randomized complete blocks with four replications. The main plot consisted of soil moisture levels at harvest time, which were tested at three different levels: a1- 21%, a2- 18%, and a3- 15%. The sub-plot involved testing the separation of peanut pods from the plant using three different methods: b1- combine harvesting, b2- harvesting with a tractor-mounted thresher, and b3- manual harvesting. The study evaluated important harvest indicators such as quantitative loss (first and second-stage losses), actual field capacity, harvest time, and the number of required laborers. The results led to the identification of the best harvesting system.
Results and Discussion
The study revealed that the optimal soil moisture content for the initial stage of harvest was 18%. For most parameters, there was a significant difference observed among treatments at the 1% level. The pull-type combine method had the highest farm capacity with a maximum of 0.46 ha per hour, while the manual harvesting method had the lowest capacity with a minimum of 0.006 ha per hour. The total losses ranged between 5.95% and 10.58%, with the manual harvesting method exhibiting the lowest loss and the pull-type combine method showing the highest loss. Furthermore, the manual harvesting method required more labor compared to the other methods.
Conclusion
Based on the obtained results, it is recommended to use a pull-type combine for the early harvesting of peanuts and a manual method for obtaining high-quality peanuts in the Moghan region.

Abstract In this study a mathematical analysis for estimating the performance rate "RP" of wheel type trenching machine was studied. The mathematical analysis quantifies the analysis and resulted in an equation. This mathematical equation was checked under different operating conditions. The practical study of the performance rate showed that the deviation of the theoretical performance rate from the actual performance rate ranged from 5 to 7% for the 60.4 and 90.5 cm trench depth, respectively. The machine field efficiency also ranged between 43 and 50.1% for 90.5 cm and 60.4 cm trench depth respectively.

Abstract Soil compaction can be naturally occurred or can be machinery-induced. Subsoiling is often applied to loosen soil compaction and decrease soil strength to levels that allow for root development and growth. Variable-depth subsoiling which modifies the physical properties of soil only where the tillage is required for crop growth has the potential to reduce labor, costs and fuel, and energy requirements. Since this study aimed to perform subsoiling operations with variable depth, the variable-depth tillage (VDT) tool was developed. A pneumatic multi-nozzles sensor has been used to simultaneously predict the depth of a soil layer in three depths (15, 30, and 45 cm), and send a signal to control the depth of the VDT tool. Evaluation of the VDT tool system was performed by two methods namely static and dynamic tests. In static evaluation, the system response time was measured to reach 95% of the proposed depths. The dynamic evaluation of the tool was accomplished in two steps in the field. The amount of fuel consumption and the travel distance of the tool tine to reach the desired operation depth were measured and compared with the common subsoiler (when the depth control was OFF). The average fuel consumption by using the variable-depth tillage tool decreased by 17.36% compared to the constant depth. Furthermore, the pneumatic sensor tine penetrated into the soil perfectly and sent the control signal to the control unit of the VDT tool in real-time, and the VDT tool loosened the soil at the exact depths sent by the sensor.

Abstract Introduction
According to FAO, gherkin and cucumber have been cultivated in about 2.23 million hectares of farmlands around the globe, and about 78000 hectares of Iran agricultural fields have been devoted to gherkin and cucumber cultivation. However, large amounts of the cucumber seeds required in Iran have been imported from abroad. Fortunately, some Iranian agricultural companies have been focused on seed production recently. Therefore, there is an opportunity to develop seed production equipment such as seed extracting machines.
There are two types of cucumber seed extractors: bulk seed extractor and single fruit extractor. The bulk seed extractor is suitable for extraction of large amounts of seed on the farm, while the single fruit extractor is suitable where seed production is limited to greenhouse seed-producing facilities which are mostly used for controlled pollination of the crop.
Due to the high price of imported seed extractors, especially after increasing the price of foreign currencies, production of these machines within the country is economically rational; therefore, the aim of this research is to develop and evaluate a single fruit cucumber seed extractor for small and medium-size seed-producing greenhouses.
Materials and Methods
The cucumber seed extractor was designed semi-automatically. The criteria for designing the machine were as follows: 1- usage of the single fruit seed extraction method, 2- the possibility of simultaneous usage of two operators, 3- automatic discharge of the extracted seeds, 4- the possibility of the height variation of the machine, 5- the possibility of the emergency shutdown of the machine, 6- the possibility of the angular velocity variation of the machine helix.
The working element of the machine was the rotating helix that can extract the fruit seeds and leave the fruit's outer skin mostly intact for easy disposal of fruit remains from the greenhouse. A 1 hp, 3 phase electric motor was used to drive the machine via the belt and pulley transmission system. For the smooth start and stop of the machine, and the possibility of angular velocity variation of the machine helixes, an electronic driver was used for the motor.
To design the machine helix, the dimensions of the examined cucumber were measured first (i.e., cucumber length and diameter); then, according to the physical and mechanical properties of the fruit, the prime mover and transmission system of the machine was designed. Finally, the fabricated machine was evaluated using some mechanization criteria.
Results and Discussion
Some of the results are as follows:

The total torque required to drive the machine was 3.394Nm.
The electric motor power should be higher than 0.284hp; furthermore, in order to have a wider angular velocity span for the rotating shaft, a 1hp electric motor was installed on the machine.
The diameter of the rotating shaft was calculated to be 15mm.
The seed extracting machine could be used instead of 15 workers of the manual seed extraction method.
The rate of seed extraction using the machine was 30781 kg ha^-1.
The efficiency of seed extraction using the machine was similar to that of the manual method.
The emergence percentage of seeds obtained by the machine was similar to that of the manual method.
The amount of crop calculated from the concept of economical break-even point was 7 tons.

Conclusion
In this study, an apparatus for mechanized extraction of cucumber seed was designed, fabricated and evaluated. The working element of the machine is the extractor helix that is rotated via the belt and pulley transmission system, which is activated using a 1 hp, 3 phase electric motor. For smooth start and stop of the motor, as well as the possibility of angular velocity variation of the machine helix, the motor was equipped with an electronic driver. Utilizing an emergency shutdown switch, the machine can be protected from unforeseen emergency situations. After using the machine for 6 months, it was recognized that strengthening the extractor helixes was necessary. According to the results of this study, using the machine led to 15 person reduction in the labor needs of the manual cucumber seed extraction method. Moreover, the amount of crop calculated from the economical break-even point was 7.7 tons.

Abstract Introduction
One of the biggest problems in growing legumes like peas is harvesting these types of crops. During the machine harvesting process the harvest loss is very high. Therefore, in most parts of Iran chickpea harvested by hand and this is very tedious. Based on the literature review there are different types of harvesting machines which designed, constructed and optimized by Miller et al., 1990; Golpira, 2015; Shahbazi, 2011; Jalali and Abdi, 2014; Mahamodi, 2016. But using different varieties of chickpea in mountainous areas has limited the use of harvesting mechanisms. The purpose of this study is mechanization of the harvesting process of chickpea with low losses and suitable performance. Moreover the optimization process of lowering the weight of the header was carried out by modeling of software.
Materials and Methods
To reduce the amount of chickpea losses from the reel, a perforated plate with defined holes was installed in the header, where the separated chickpea pods fell behind the plate without returning to the farm. By using the plate in the header of the chickpea harvesting machine and by changing the harvesting height at the three levels of 10, 15 and 20 cm and the distance of the cutter at three levels of 3, 5 and 7 mm, the performance of the machine was evaluated. The experiments were carried out with Caboli variety cultivated in Kurdistan province, which is proper for mountainous areas without regular watering condition in three replications. The plants were placed in a fiber, wooden plate considering farm conditions. In addition, the header was modeled statically and dynamically under the influence of the external forces applied to the header using Ansys and Abaqus software. Based on the actual data, the validity of the applied model was determined and according to the verification results the optimization of the header was performed considering minimal weight (to reduce energy consumption).
Results and Discussion
The evaluation results of the performance of header showed that the effects of using perforated plate and the height of the header for harvesting on the chickpea harvesting and losses are significant at the level of 1% and 5%, respectively, and the interaction between perforated plate and the header height on the chickpea loss is significant at 5%. Using a perforated plate in the harvesting machine increases the amounts of chickpea collected from the farm increases. In this condition the chickpea pods separated from the plant and passed through the plate. With the separation of the stems, due to the proper wear that exists between the plate and the reel, the pods are properly separated and pass through the perforated plate. Moreover, the chickpea loss is higher for the system without perforated plate. The effect of the distance between the reel and header plate is affects the remaining chickpea on the plate. By increasing the distance from 5 mm to 7 mm the amount of harvested had a considerable effect. The best method of harvesting chickpeas is at the kinematic index of 1.5 with perforated plate, the harvesting height of 15 cm and the distance of 5 mm. According to modeling processes of the reel and the results of the static analysis, the minimum and maximum stress values were recorded about 3.31 MPa and 6.50 MPa (based on the von misses criteria), respectively, which is very small compared to the yield stress of the reel constructed with St-37. Also, the results of the dynamic analysis of the reel showed that the maximum von misses stress occurred with increasing the kinematic index. The maximum stress for kinematic index of 1, 1.5 and 2 was observed about 32.2, 40.1 and 52.72 MPa, respectively. The results of 3D model validation showed that the applied model with Abaqus software (R²>0.9264) was able to predict the amount of stress in different parts of the reel.
Conclusion
In this study, the changes were made on the chickpea harvesting machine to get the proper performance and increasing machine efficiency. A perforated plate was used to prevent pea’s losses. The best condition for the harvesting process is obtained with the harvesting height of 15 cm and the distance of 5 mm. By using 3D modeling of the reel weight was reduced about 10%.

Abstract Introduction
Seedbed preparation, seeding, and transplanting are usually based on mechanical soil tillage. Tillage by cutting, mixing, overturning, and loosening the soil can modify the physical, mechanical, and biological properties of soil. These days, because of soil protection, the use of tillage tools is less and less recommended, and some implements such as cultivators are preferred to primary tillage tools such as plows. Experimental study of soil-tool interaction and field measurements of the mechanics of tillage tools are usually time-consuming and costly. On the other hand, the variety of variables and uncontrolled conditions add other dimensions to the complexity of this method. Also, the experimental and analytical methods do not have a comprehensive view of stress distribution and soil deformation in the soil-tool interaction process.
Materials and Methods
The main purpose of this study is to validate the results of numerical simulations in two phases of experimental tests: in soil bin environment and in finite element computer simulations. Experimental tests were performed in the soil bin environment of the Department of Mechanical Engineering of Biosystems, Urmia University, which has a soil bin facility with dimensions of length and width of 24 and 2 m, respectively, and has clay loam soil. Before experimental tests, soil preparation was performed by using some special tillage implements (harrow, leveler, and roller) which were attached to the soil bin (Figure.1). For experimental tests, a mechanism set consisting of two cultivator blades with a width of 15cm, a length of 20cm, and at a spacing of 35cm from each other was prepared and constructed. The relevant mechanism is designed to have the ability to change the tillage depth. Data were collected at three different soil depth levels of 6, 10, and 14cm in the soil bin with three replications. Data recording was performed using a 10-channel data logger with load cell connectivity and data storage ability. Also, in this study, the Drucker-Prager model as a finite element simulation method was used to calculate the stress during the soil-tool relationship. ABAQUS 6.10.1 software was used to simulate the cultivator tine. To solve the problem, the soil parameters were defined as presented in Table 1, and then the interaction between the soil-tool model and the necessary constraints, including boundary conditions, were defined. In the next step, meshing was applied to the constructed model.
Results and Discussion
In the results section, first, the results related to the amount of traction force required for the tillage tine in the simulation were calculated and then compared with the soil bin experimental tests. The traction force of the finite element simulation results for three tillage depths of 6, 10, and 14 cm in three principal directions is shown in Figure 4. A comparison of simulation and experimental results showed that there is a good agreement between them. In comparison, the simulation error range of the three depths of 6, 10, and 14 cm has shown 7.3, 5.6, and 4.16% at a speed of 2.5 kmh^-1, respectively, as the velocity studied in this research. In the next section, the results of stress distribution contours in the soil and finally the overlap of the blade effect were discussed. Figure 6 shows the status of stress contours at three depths. By increasing the depth of the tine at the three depth levels studied, the stress range is shifted from the soil surface to its depth. For this purpose, at the maximum depth studied in this study (14 cm), it shows that the stress propagation to the soil surface is less than at other depths. Also, with decreasing depth, for a depth of 6 cm, the maximum stress was on the top soil surface, in other words, more deformation was seen on the soil surface.
Conclusion
Comparing the simulation results for predicting traction force with the results of experimental tests has led to relatively acceptable results and the maximum traction force prediction error at different depths has been about 7.3%.
The distribution of stress in the soil was observed due to the tine depth. The highest intensity of stress propagation was observed at the soil surface; and the highest soil surface deformation at a depth of 6 cm. With increasing depth, both parameters of stress and soil surface deformation have decreased. According to the results of the studied blades, it is better to use these types of tillage tools only at lower depths. Also, in evaluating the overlap of the soil loosening zone in the side-by-side tines, it proves the superiority of the tine performance at lower depths.

Abstract Introduction
Sugarcane cultivation in Khuzestan province is in the form of planting in-furrow. Due to the fact that in a machine harvesting, the reaper is not able to fully harvest the straw in the furrow, in the planting in-furrow method, it is necessary to transfer the rows of straw to the stack. So one of the measures at the time was hilling up operations or stacking reeds planted in the furrow. Therefore, due to the salinity of irrigation water and high groundwater levels, which have increased the salinity of sugarcane fields in Khuzestan province, planting this product in summer to protect the seedlings against salinity is mandatory in the furrow. On one hand, due to the difficulty of harvesting operations in the furrow during the harvest season, and on the other hand, because of the reduction of waste during harvesting, the plant needs to be located on the ridge. Therefore, in sugarcane fields, when the seedlings are established and grown, the furrow and ridges are replaced, and to perform this operation special machines are required. According to the study, so far there has been no scientific and reasoned report on the study and evaluation of different types of hilling up devices and different speeds in sugarcane cultivation, and the use of machines in sugarcane cultivation and industry is based solely on objective observations. Therefore, in this study, three different types of devices have been evaluated in two soil textures and three different forward speeds as a step towards choosing the best type of machine and optimal speed of hilling up operations in sugarcane cultivation.
Materials and Methods
The purpose of this study was to evaluate three different methods of sugarcane hilling up in two soil textures and three different forward speeds. Research treatments include: soil texture (clay loam and silty clay loam), hilling up methods (6-shanks subsoil + 10-shanks subsoil, 8-shanks subsoil + hilling up device No. 1 and 8-shanks subsoil + hilling up device No. 2), and forward speeds (5, 6, and 7 kilometers per hour). Design of a factorial experiment based on randomized complete block design with three replications in Amirkabir field 208 (ALC 200 field 8) with clay loam texture and cultivar CP69-1062 and farm ARC14-22 with silty clay loam texture and cultivar CP69-1062, 15% moisture, and first-year cultivation was performed. The test plot includes 108 furrows. The area of each plot was two furrows. The length of each furrow was 250 meters (equal to the length of the sugarcane rows). To avoid affecting the interactions of the treatments, a distance was given between the treatments. The farms being tested were newly cultivated farms. The surface of the farm was furrowed and ridged. Care was taken in selecting the farm so that the humidity was similar in its different sections. After setting the right time for the hilling up and before starting the operation, soil sampling is required to determine the soil cone index and soil moisture. The physical properties of this study include Mean Weight Diameter (MWD), bulk density, soil surface uniformity, soil water permeability, and furrow depth (stack height). Analysis of variance and Duncan test were used to compare the treatments using SAS 9.4 software.
Results and Discussion
The results showed that there was a significant difference between soil Mean Weight Diameter, bulk density, soil surface uniformity, and soil water permeability in soil texture treatments, type of hilling up machine, and forward speed. Furrow depth index (stack height) was significantly different in treatments of type of machine and forward speed but not in soil texture treatments. The comparison of means showed that the whole loam texture treatment had 6-shanks + 10-shanks at a speed of 7 km h^-1 with the smallest mean weight diameter (16.06 mm). The use of 6-shanks subsoil + 10-shanks subsoil in hilling up in whole texture and speed of 5 km h^-1 significantly reduced soil bulk density. The lowest coefficient of variation of soil surface uniformity was obtained with 8-shanks subsoil + hilling up device No. 1 in clay loam texture and 7 km h^-1 forward speed. The highest rate of water permeability in the soil was obtained after the hilling up operation with 6-shanks subsoil + 10-shanks subsoil in a total texture of 2.32 cm h^-1. Furrow depth index (stack height) was also within the acceptable range (10-15 cm) in all treatments. But in addition to height, the appearance of the ridges is also important. In the treatment of 6-shanks + 10-shanks in plant stacking and embankment operations, sometimes in fields, there are parts where this operation is not done well and the machine is not capable enough and is in the middle of the created ridges. Harvesting operations do not cause proper reed flooring. Therefore, to solve this problem, it is necessary to perform the hilling up operation at the appropriate speed and humidity so that the soil is well placed on the rows of reeds and the proper appearance of the ridge is maintained.
Conclusion
In this study, three different types of devices have been evaluated in two soil textures and three different forward speeds as a step towards choosing the best type of machine and optimal speed of hilling up operations in sugarcane cultivation. The physical properties of the soil, including the soil Mean Weight Diameter, bulk density, soil surface uniformity, soil water permeability, and the size of the furrow depth (ridge height) were measured, and the best treatments were identified. Considering the importance of hilling up operations in sugarcane cultivation and to complete the results of this experiment, the following items that could not be studied in this study are suggested. The effect of using different methods on hilling up should be investigated on the yield of sugarcane. The effect of using different devices on hilling up in terms of tensile strength, work efficiency, and time required to do the work, fuel consumption, cost of timely work, and maintenance costs in operations on sugarcane hilling up should be investigated.

Abstract Introduction
The nut sunflower is usually cultivated in small farms and is harvested with a low capacity of harvester at high moisture content. For the rigid threshing components, impact and knead force are so large as it leads to crushing of the grain or inner stress. This reduces marketability and the germination rate of seeds. The mechanical damage degree of sunflower grain is influenced by the material of the threshing beaters, the velocity of impact, moisture contents, etc. Traditional manual methods, that separate grain from the sunflower head, take a lot of time, require large manpower, have high grain damage, and low efficiency. The objective of the present work was to develop and optimize a threshing unit for nutty sunflower that would combine safe impact velocities with appropriate adjusting of its variable to maximize threshing efficiency whilst minimizing grain damage resulting from shearing, cracking, or crushing.
Materials and Methods
The nutty Sunflower heads were procured from the Experimental Orchard of University of Tabriz, Iran at the moisture content of harvesting. Axial threshing units using kinematic equation and properties of the grain, designed and constructed that the variables of its components are adjustable. The beater of the thresher is flexible, which the deformation and vibration undergoing the overall rotation and impact process becomes larger with increasing speed and prevents grain damage. The power required for threshing and separation grain from heads was calculated at about 4.5 kW. Diameter and rotational drum speed value estimated using relation (V=  and study of other researches as considering critical impact velocity of sunflower grain. The length of the thresher was 1.2 m that estimated by determining the capacity and the number of beaters. Threshing efficiency (%), separation efficiency (%), and grain damage (%) were parameters of performance for study. The experimental design by the Response Surface Methodology in Design Expert software 11 with central composite experiment design developed and the affecting parameters on accuracy analyzed and optimized. The threshing unit was evaluated against three threshing drum speeds of 380, 280, and 180 (rpm), feed rates 4000, 3000, and 2000 (kg (head)h^-1), moisture content of 60%, 45%, and 30 (%w.b).
Results and Discussion
The results showed that the models and effect of variables were statistically significant at the 95% confidence level. The moisture content on threshing efficiency and grain damage had the greatest effect followed by drum speed and feed rate. While for separation efficiency, the feed rate had the most influence. With reducing feed rate and moisture content the threshing efficiency increased, although the decrease in drum speed reduced it. This might be due to sunflower grains adhering loosely to the head at the low moisture contents. The maximum (99.81) and minimum (96.12) percentage of threshed heads was at the moisture content of 30 and 60, respectively. The separation efficiency increased with reducing of feed rate and moisture content. Though, drum speed had insignificant efficacy statistically. The sunflower heads with high moisture content are fragile and brittle, also at high feed rates, the number of impact forces and collisions of heads rises in the condition of threshing. Therefore, the extra MOG is produced and passed from the separator grille. The feed rate of 2000 kg h^-1 and moisture content of 30% was the maximum point of separation efficiency that obtained 69.82%. The grain damage decreased significantly with reducing drum speed (380 to 180) and moisture content (60 to 30). This result may be due to the reasons that at higher moisture content the husk of grains becomes soft. The goal of optimization is maximizing threshing and separation efficiency and minimizing grain damage that the optimized values of variables were determined 292.134 rpm for drum speed, 2000 kg h^-1 for feed rate, and 30.7406% (w.b) for moisture content.
Conclusion
A threshing unit of sunflower, using properties of grains and kinematic equation, was designed and constructed. The models and effect of the variable were statistically significant on performances. The moisture content had a greater effect than other factors on threshing efficiency (%) and grain damage (%). Also, the feed rate of crops in thresher had the most influence on separation efficiency (%). With decreasing the moisture content, threshing and separation efficiency increased and grain damage reduced. The threshing efficiency (%), separation efficiency (%), and grain damage (%) were reported in the range of 96.12 to 99.81, 57.34 to 68.55, and 0.49 to 1.25, respectively. The optimized points were determined at the drum speed of 292.134 m s^-1, feed rate of 2000 kg h^-1, and moisture content of 30.7406% (w.b).

Abstract The main aim of this study was to optimize the design parameters of the fruit shakers for efficient harvesting of Shengy olive. A single-degree-of-freedom spring-mass model was established to determine the natural frequency and damping coefficient of the limb. A tractor-mounted shaker that transmits vibration to limbs and fruits via a reciprocating mechanism was fabricated for field evaluation of the forced vibration modes. A 3×4 factorial experiment with a completely randomized design was conducted to investigate the effects of shaking amplitudes and frequencies on fruit removal. The shaking mode with a frequency of 10 Hz and amplitude of 80 mm transmitted the average power of 92 W to remove 95% of fruits in the field trial. This oscillation characteristic should be used to redesign the fruit shakers to pass human safety standards and efficient harvesting.

Abstract Introduction
According to reports on trends in the agricultural industry, demand for more precise and affordable machinery is rising and precision farming methods used by farmers are expanding. Damping vibration of the boom sprayer is one of the challenges for researchers when crossing the surface roughness. The lack of uniformity of the nozzle spray pattern and the reduction of the precision and quality is the result of an uncontrolled vibration of the boom sprayer. So far, many efforts have been made to decrease the vibration of the long sprayer boom. Using active and passive methods, researchers have achieved great success in reducing the spray boom vibration. Many of these methods are based on the use of external force as a controlling force. Expensive equipment, the use of tractor hydraulic power, and high energy costs are the main disadvantages of these methods. In the present work, a new system called "variable support" was designed and built. The boom rests on a round bar at its midpoint; as the boom tends to oscillate, a minute amount of rotation of the bar activated by a servomotor in an appropriate direction, alters the position of the resting point of the boom on the supporting bar, bringing the boom back to its initial balanced position as a result.

Materials and Methods
To carry out experiments, the universal tractor U650 and a mounted tractor sprayer model tms500 with 8 m boom and a 500-liter tank, was used in this research by making changes to the design of the simple tractor sprayer a new active sprayer designed and built with intelligent online balancing system that in addition to balancing the boom angle, it reduced the fluctuations that occur during work. Electronic control was used to control the position of the boom. The microcontroller programming codes were developed and uploaded in the microprocessor to execute instantaneous commands to the mounted activator due to the need for boom positional data for analyzing experiments, a data logger was also designed in conjunction with the controller circuit and the algorithm was loaded after coding with C++. To compare the new sprayer with the conventional, a field test was conducted. Tests were carried out according to manufacturer's instructions at three-speed levels of 3 (low), 5 (medium), and 8 km h^-1 (high), with three bumps heights of 10, 15, and 20 cm with three replications. For the acquisition of vertical acceleration as well as axial rotation data in the conventional sprayer, a data logger with an accelerometer and gyroscope was used. The data logging rate and the accuracy of the accelerometer and gyroscope measurement were set to 50 Hz, 0.1 m s^-2 and 0.1°, respectively.

Results and Discussion
To compare the behavior of the active and the conventional spray booms in terms of vibrations, the univariate analysis was used. The results showed that there was a significant difference between the performances of two sprayers at 5% probability level with the sig. number of 0.000.
To compare the behavior of the active and the conventional spray booms in terms of axial rotation, also the Univariate analysis was used. The results showed that there was significant difference between the performances of two sprayers at 5% probability level with the sig. number of 0.000. Also, comparing the marginal mean values of the data obtained from the data logger showed that the active boom compared with the conventional boom had less axial rotation and less vertical acceleration.

Conclusion
Results of experiments showed that the new sprayer with variable support system, relative to the conventional sprayer in terms of controlling boom acceleration and the angular balance of the boom with a significant difference had relative superiority and can be considered as an appropriate alternative to increase the accuracy of spraying, although more research on large scale booms are necessary before coming to final conclusion.

Abstract Introduction
Almonds (Prunus amygdalus) belongs to the family of Rosaceae and the subspecies of Pronoideae. Its kernel contains a lot of energy, amino acids, sugars and mineral elements. Iran is ranked fifth in terms of producing almonds after United States, Australia, Spain, and Morocco, but at the same time, Iran's position is not very suitable in the world export market. The processing of this product involves three stages of shell breaking, kernel separation, and packaging. One of the important methods of separation of the kernel from the wooden crust is the use of pneumatic separation and this method can be used to grade, clean, and separate the seeds of different materials.

Materials and Methods
Almond samples of the Shokofeh variety (A.H.3) were obtained from Maragheh gardens in East Azarbaijan province. The moisture content of the shell, the kernel, and mixture of them was determined using the oven drying method. Also, some physical and mechanical properties were measured. In order to design the almond separator system, it is important to determine aerodynamic properties. The most important aerodynamic properties such as terminal velocity and drag force were determined. The first step in designing and manufacturing a device is to select the cross-sectional shape and dimension. The cross-section of the machine is selected based on parameters such as simplicity and construction costs. With the assumption of a machine with a separation capacity of 2 kg (mixed product) per minute, the length and the width of the machine were obtained to be 18 cm and 15 cm. Using the terminal velocity and dimensional data, the blower distance to the outlet, the tunnel length, the power and flow rate of the blower were calculated and then the design and construction were done. To evaluate the separation and evaluation of the apparatus, parameters such as blower speed, shell size, and moisture content of the mixture were investigated for each parameter at three levels. Airflow rates of the wind tunnel were 3, 5, and 7 m s^-1, moisture content (7%, 13%, and 19%), shell size in three groups: small, medium, and large.

Results and Discussion
The average geometric properties including length, width, thickness, geometric mean diameter, and spherical coefficient for almonds were 20.64, 13.25, 7.4, 12.64 mm, and 0.612, respectively, as well as properties for large shells (25.17, 16.5, 11.15, 16.66 mm, and 0.66), for average size (17.36, 13.5, 6.4, 11.44 mm, and 0.65) and fine size (13, 9.9, 3.5, 7.66 mm, and 0.59), respectively. The mechanical properties of the samples (shell and almond kernel) were measured at three levels of moisture content of 7%, 13%, and 19%. The results showed that by increasing the moisture content, the fracture force for both shell and kernel increases. Almond shell had the highest angle of rotation at all levels of moisture. This was due to its heterogeneous shape, broken edges and rough surface. On the other hand, almonds had the lowest degree of rotation, due to the greater weight of the kernel and the more homogeneous and spherical shape than the shell. The results obtained from measuring the terminal velocity of the samples selected from the kernel and shell in terms of their weight indicated that the velocity limit for the almonds was 10.2-12.2 m s^-1 and for the shell, the range was 1.8-6 m s^-1. The variance analysis of the effect of particle size, velocity, and moisture parameters on the level of separation of shell in almond mixture showed that all major effects and interactions of factors were significant at 1% probability level. Particle size and moisture content did not affect the separation rate at 7 m s^-1. With decreasing velocity, the separation rate in the particle size was reduced, which was due to the higher speed of the separation rate. At low velocity, the best separation was related to the fine particle size, which was due to the harmonization of the fine particle velocity and the separation rate.

Conclusion
Pneumatic separation of almond kernel and shell was affected by air velocity, particle size and moisture content. As the flow rate increases, the amount of shell separation from the kernel increases. Particle size and moisture content did not affect the separation rate at 7 m s^-1. The results at medium moisture content indicated that in addition to the acceptable separation level (relative to other moisture levels) at this level (13%), the harvesting time of this product can be managed and the use of additional energy in the processing of this product is prevented.

Abstract Introduction
Sunflower planting is mostly carried out for two particular purposes; oil production and as nut. Harvesting is one of the biggest problems in both types of sunflower. The difficulty of harvesting and less scientific research have led us to study the mechanized harvesting of this kind of crops. In this research, head losses and grain losses for the inner section of combine were investigated during mechanized harvesting of oily sunflower and a regression model was used based on the experimental tests for head losses and grain losses in the inner section of the combine.
Materials and Methods
After preparing an especial head for harvesting sunflower, the head was set up on the combine for measuring the harvest losses. The cutting, threshing and clearing process for sunflower seeds were done during the tests. The design of the head is the same as the sunflower bushes are firstly bent by the bar and then sequentially the cutting, and transferring processes are done. The tests were implemented in an oily sunflower farm by a combine harvester (1055 john deer) in 3 replications. The farm performance was 2170 kg ha^-1 and was located in Kermanshah province in Iran. A pre-test was done to define the best combine forward speed and finally 2.5 km h^-1 was adjusted for combine forward speed. The bar height (BH) in two levels (20 and 70 cm) and head height (HH) in two levels (60 and 120 cm) were independent parameters to evaluate the head. The dependent parameters were the combine losses and head losses. For the analysis of variance of the variable parameters, a 2×2 factorial plot with 3 replications was used. A regression model was defined based on experimental tests.
Results and Discussion
Having done the experimental tests, data were analyzed and the effect of independent parameters on the head and combine grain losses were investigated. The effect of the bar height on the head grain losses was significant at 1% level and the effect of the head height and interaction between bar height and head height on the head grain losses was also significant at 5% level. Results showed that with increasing in bar height, the head grain losses increased. With a change in the bar height, the location of the cutting point is changed and this led to a change in the head grain losses. The effect of the bar height on the combine grain losses was significant at 5% level but the effect of the head height and interaction between bar height and head height was not significant on the combine grain losses. Increasing in the bar height led to increase in material other grain (MOG) which enters to the combine, and also resulted in increasing in combine grain losses. The coefficient of determination of head grain losses in the regression model was 0.97. The model was able to explain the relationship between the bar and head height with head grain losses due to the relationship between independent and dependent parameters. The amount of R-squared for the combine grain losses in the regression model was 0.53. Because of the effect of other parameters in the inner section of the combine, the output of the model predicted that increasing in the bar height and head height, resulted in increasing in head grain losses, and also increasing in the bar height and decreasing in head height let to increasing in combine grain losses. The output of model showed that regulating the bar height and cutting height could reduce the harvest losses by less than 3%. This R-squared is obviously less than R-squared of head grain losses model. The output of the regression model predicted that the increase in the bar height and head height was associated with increase in the head grain losses, and increasing in the bar height and decreasing in head height, resulted in increasing in combine grain losses. The output of the regression model showed that the harvest losses can be reduced less than 5% by regulating the bar height and cutting height.
Conclusion
One of the most important parameters for mechanized harvesting is the head mechanism which cuts the crops and transfers them to the threshing unit. The cutting height in the sunflower head was defined by the bar height and head height. According to the linear relationship between the head and combine losses with the bar height and head height, and the interaction between them, the regression model was able to predict the result successfully. This model of grain losses in the head and combine model can be used in the intelligent combine to minimize the harvest losses. The optimization of the bar height and head height for minimizing the harvest losses can be the subject of next researches.

Abstract Introduction
Safflower (Carthamus tinctorius L.) is an oil plant with a growth cycle of 120 days. The seeds of this crop are primarily used for oil production, while its flower petals are used for extracting natural pigments and medicinal purposes. The cultivation area for this crop in Iran was about 2300 ha during 2014-2015. Due to the recent droughts, cultivation of this crop has a good income for farmers because of the short growth period, resistance to drought (water stress) and less maintenance requirements. In the meantime, the flower petals of this crop are used for food coloring and medical affairs. The flower petals are harvested with the traditional method in most parts of Iran, which has a lot of hardship for harvesting and increases production costs. On the other hand, this crop is contaminated in terms of sanitary factors due to the contact of the worker hands with flower petals. Therefore, applying a proper mechanization method for petals harvesting is an effective step in the development of this crop cultivation.
Materials and Methods
In this study, three petal harvesting methods including the manual (conventional) method, Knapsack (Indian modified) method and Fossil-fueled wheelbarrow machine method were compared in terms of effective field capacity, downfall loss percentage, purity percentage, energy consumption, and harvesting costs. The Indian knapsack machine was modified. The experimental design format was a Randomized Complete Block Design (RCBD) with three replications‏. In the knapsack method (modified), petals were separated from the receptacle by a cutting blade and sucked into the machine reservoir. In the manual method, petals were separated from the reception by the worker hands and put inside the special bags which hanged on the worker neck. In the fossil-fueled wheelbarrow machine, an 8 kW motor-powered engine was used to set up the 1200 w vacuum system and cutting unit. The vacuum system was installed on the special chassis in wheel barrow machine. Each experimental plot had about 149 safflowers in one square meter area, which was harvested in different methods.
Results and Discussion
The results showed that the harvesting loss (W.W.) of the Knapsack method, Fossil-fueled wheelbarrow machine method, and manual method were 0.63%, 1.11%, and 3.25%, respectively. The percentages of purity were 97.71%, 98.66%, and 95.29%, respectively. There was a significant difference between machine and manual methods in 5% level. The effective field capacity of the methods was 2.45, 2.76, and 1.39 g min^-1 (in dry condition), which was not significantly different between the machinery treatments in 5% level. The energy consumption for the fossil-fueled wheelbarrow machine was significant compared to the other two methods (1356 kW h^-1 in 30 days). In terms of the economic point, benefit-cost ratios were 1.75, 1.55, and 1.16 for the Knapsack method, Fossil-fueled wheelbarrow machine method, and manual method, respectively. If the solar panel was used in the Knapsack method, the benefit-cost ratio would decrease to 1.54.
Conclusion
The field capacity of machines methods was more than manual method for safflower petal harvesting. The Knapsack machine had less loss percentage than other treatments. The wheelbarrow machine had a higher degree of purity, but no significant difference was observed between this treatment and the Knapsack method. The energy consumption of the wheelbarrow machine was higher than other treatments. The economic evaluation showed that the Knapsack machine had a higher benefit-cost ratio than other treatments. If the solar panel was used by this machine, the use of a solar panel system would be economical too. Finally, with regards to the technical and economic parameters, using the Knapsack machine was recommended for safflower petal harvesting.

Abstract Introduction
The annually production of cattle manure is estimated around six million tons in Iran. Manure transportation with high moisture and low density recognized as crucial issue. The densification of dry or wet manure is the profound method for decreasing the manure volume which reduces the cost of handling and storage. Besides, the particle size is one of the important factors in the pellet production. Ball mills, vibratory mills, hammer mills, knife mills, two roll mills, colloid mills, attrition mills, or extruders can be used for size reduction of biomass. Specific energy consumption for size reduction of biomass highly depends on moisture content, bulk and particle densities, feed rate of the material, particle size distribution (initial/final particle size) and machine variables. The present study is conducted for wet cattle manure size reduction machine. Furthermore, the relationship between moisture content (35, 40 and 45 %w.b) and drum of special size reduction machine in rotational speed (150, 200 and 250 rpm) considering geometric mean diameter of particle and size distribution of wet cattle manure were investigated. A factorial experiment under randomized complete design method was employed with three replications.
 
Materials and Methods
The main parts of machine include drum, concave, spring and adjusting screw. The main function of this thresher machine is to combine crushing and cutting in order to conduct the size reduction methods, i.e., to apply compressive and shear forces to the cattle manure particles. The drum is also equipped with several rows of sharp-edged milling segments. The spring constants were determined by evaluating the slope of the force vs. deflection curves. The rotational speed of drum was changed in the range of 100-700 rpm during these experiments. In the test of the machine physical properties of grinds such as geometric mean diameter of grind particles and particle size distribution were determined. One kg of cattle manure was grinded in each test and the particle size distribution of grinded cattle manure was determined according to ASAE standard S319.3. The moisture content of cattle manure was obtained according to ASAE standard S358.3.
 
Results and Discussion
The initial and final particle size of the materials are 20 millimeters and less than 5 millimeters, respectively and the angle of nip is 30 degrees (according to the installation space limitations), the diameter of the drum is 310 millimeters. The spring constant was equal to 24.371 N mm^-1 and on the basis of the experiments a drum speed in the range of 150–250 rpm is considered to be optimal settings for the milling for cattle manure disintegration. The results of Table 4 show that for wet cattle manure with 35% (w.b) moisture content at 250 rpm rotational speed of drum (P > 0.05; Skewness = -0.056; Kurtosis = -2.15), 40% (w.b) moisture content at 250 rpm rotational speed of drum (P > 0.05; Skewness = 0.076; Kurtosis = -1.77), 45% (w.b) moisture content at 200 rpm rotational speed of drum (P > 0.05; Skewness = 0.095; Kurtosis = -1.72), in grinds that would potentially produce better compacts. The geometric mean particle size and standard deviation for each test are shown in Table 2. According to Table 2, the lowest geometric mean of particle size is related to rotational speed of 200 rpm and a moisture content of 45% (w.b), and the highest at rotational speed of 250 rpm and a moisture content of 45% (w.b) can be observed.
 
Conclusion

The use of cattle manure of thresher machine reduces the specific energy consumption of cattle manure by 92% compared to the conventional method (using drying and hammer mill) in the pellet production.
The lowest geometric mean diameter of wet cattle manure was 1.02 millimeter for drum rotational speed of 200 rpm at 45% (w.b) moisture content and the highest was 1.38 at rotational speed of 250 rpm and a moisture content of 45% (w.b%).
The best particle size distribution was observed for milling of wet cattle manure with 35% (w.b) moisture content at 250 rpm rotational speed of drum (P> 0.05; Skewness = -0.056; Kurtosis = -2.15), 40% (w.b) moisture content at 250 rpm rotational speed of drum (P> 0.05; Skewness = 0.076; Kurtosis = -1.77), 45% (w.b) moisture content at 200 rpm rotational speed of drum (P> 0.05; Skewness = 0.095; Kurtosis = -1.72)

Abstract Introduction
Tillage is a very important operation that influences the growth and productivity of agricultural products. It is necessary to introduce some conditions to improve soil physical properties, aeration, permeability and root development in tillage operations. However, in primary tillage, especially when moldboard ploughs are used, this may be time consuming and costly for researchers to use it in their research. Some researchers use physical experiments to perform the work, which the accuracy of the results is dependent on the measuring instruments precision. However, some other researchers use simulation and mathematical modeling to reduce the time and costs and increase the relative accuracy of the research results. Many studies have also shown that modeling the forces involved in tillage is a good way to estimate the performance of different tillage tools and improve their geometry. However, the key to success in numerical simulation of tillage operations is to simulate the exact instrumentation, based on the correct assumptions as well as the proper methods. The prediction of the forces involved in tillage tools has an important role in their design. Collecting data on the forces involved in tillage tool under different farm conditions is a time consuming and costly task. Therefore, the prediction of a tillage tool forces is very important for the designer and the user in order to achieve better performance of the tool.
Materials and Methods
In this study, a cylindrical moldboard made by Alpler Company in Turkey was used to simulate the moldboard. A measuring device was designed and constructed to measure the various points of the desired moldboard. Then, the spatial points obtained by the measuring device were presented to the SolidWorks 2016 software and the desired moldboard was modeled. The finite element method by Abacus 2016 was then used to simulate the interaction between soil and moldboard. Treatments used in simulated tillage operations included tillage depths (5, 10, 15, 20 and 25 cm) and forward speed (1, 1.5, 2, 2.5 and 3 millimeters per second). The independent variables were considered as tensile, vertical and lateral forces (Kilo newton). After simulating the tillage operations, tensile, vertical and lateral forces were obtained. These forces were modeled using response surface and artificial neural networks techniques. Then, the obtained models were compared using R2, RMSE and MRDM statistical indices and the best model was selected.
Results and Discussion
When using the response surface method, the quadratic model was selected by using the maximum value of the statistical indices R2, R2a and R2p, among the linear, two-factor and quadratic models. Then, the significance of model variables was evaluated by using variance analysis. The forces were also modeled by using the neural network method. According to the fitting curves and statistical indices of R2, RMSE and MRDM for the tensile, vertical and lateral forces, it is revealed that both methods could well predict the forces but artificial neural network was more suitable than the response surface method. Moreover, by investigating the interactions of tillage treatments and forward speed on the forces in this research, it was observed that by increasing the depth of tillage and velocity, tensile, vertical and lateral forces were increased nonlinearly by 66.55%, 68.47%, and 64.76%, respectively.
Conclusion
Regarding all the results obtained from this study, it can be concluded that the developed models using the artificial neural network in this research was a good and powerful tool for predicting the forces involved in moldboard ploughs both in the field operations and in related studies. It is also recommended that the developed models in this study can be used to manage the tillage operations, such as selecting the proper tractor. However, it is also suggested that other affecting factors, such as moldboard angles, should be included in future models to increase the ability of the model to predict the forces involved in moldboard plows.

Abstract Introduction
The issue of noise pollution is one of the concerns of most societies and industries because of their relationship to the environmental comfort of life or work of people are paying attention. The Aero-acoustics not only because of government regulations on the noise pollution, but also due to the increasing demand of the people's living standards and create a safe environment for farm animals is considered important. At the same time, products with high aero-acoustic performance will attract a lot of customers, which is in the interest of the global economy. Reducing current noise is often accompanied by a reduction in energy costs, resulting in durability of structures and improved product quality.
Materials and Methods
Sound measurements were carried out at the wind tunnel in Tabriz Tractor Engineers Company. Using the measurements performed by the instrument, the sound levels were measured at different periods of the fan. In many practical applications that include turbulent flow, no noise has any specific tone and the sound energy is continuously distributed over a wide range of frequencies. In cases where broadband noise is present, statistical disturbance values easily calculated from the RANS equations can be used in conjunction with semi-experimental correlations and audio coordination to reveal some broadband noise sources.
Based on the problem, the boundary condition is the type of "input velocity" for the input and "output pressure" for the output. It was also used to move the mesh to apply the rotary motion of the fan. The thermodynamic conditions at these boundaries should be considered.
Results and Discussion
The accuracy of the simulation results data was verified with the measured data. In the laboratory results, the audio level is accompanied by an audio environment and an inverter and a belt that is about 15 db. With this in mind, the simulation results had a good agreement with experimental results.
The velocity is a critical parameter in fan-related discussions. In the upper part of the fan, the speed of the air increases as the fan sucks, and this speed will increase as the fan approaches. In the second part, which includes the fan, for speeding objects, the speed will increase as the radius increases (due to the constant rotational speed), so the maximum speed will be at the tip of the blades. In the lower part of the fan, the speed will decrease as the fan impact decreases on the air molecules as well as the boundary layer behavior near the walls.
As the speed and intensity of the turbulence are higher at the tip of the blades, hence the kinetic energy of these regions must also be higher. The kinetic energy of the turbulence in these areas is the highest. At the bottom of the fan, it is also observed that the kinetic energy of the turbulence has been relatively high, due to the existence of flow vortices that emerge from the fan period and the presence of positive and negative pressure (negative pressure due to suction of the fan center). The high pressure difference on both sides of the fluid particles causes a rotating flow in the particles, which affects the adjacent particles and causes vortex formation.
Conclusion
The results showed that the numerical acoustic evaluation simulates the performance of the broadband band with good results and has good agreement with the effects of the current on the noise. Increasing the recognition of the factors and their effects on the fan noise level can help to reduce the noise effects of turbo-machines. Using numerical simulations in predicting and reducing noise, in addition to time saving, dramatically reduces costs by using direct methods and mechanical design physically. With regard to all aspects and calculations, it can be concluded that acoustic numerical simulation and broadband noise model have a good ability to analyze noise in fans and rotary machines.

Abstract Introduction
Due to problems such as water resources constraints, poor soil and soil organic matter, and the problems related conventional tillage, the attention paid to protective tillage equipment should be taken into consideration by farmers. Today, agricultural machinery designers and manufacturers are looking for ways to resolve the problems due to the lack of water and soil resources and the reduction in fuel resources. One of these solutions is the optimization of agricultural machinery. The blade is one of the most important consumed components of tillage tools, which is very important for how it is adjusted and its effect on soil. According to research conducted on the importance of optimizing tillage implements, this study was carried out with the aim of optimizing the operating conditions for combined tillage with a new narrow blade.
Materials and Methods
The tests were taken place in the 10th section of farms in Agriculture school (Bajgah zone) of Shiraz University. Those tests were arranged as the split-split plot based on a completely randomized design. The treatments included the tillage depth, tilt angle and forward speed. The levels for the tillage depth, tilt angle and forward speed were 15, 20 cm and 0, 10, 15, 20, 25 degree and 3, 4, 5 km h^-1 respectively. The experiments were performed in three replications. The test variables were draft, soil upheaving and disturbance areas, specific draft, fuel consumption and tractor wheel slippage. The CK 45 steel was used to make blades. The blades were made of the same dimensions and the difference between the blades was only at their tilt angle. Before starting the field tests, some properties of soil such as soil moisture content, soil texture and soil bulk density were measured. The RNAM test code was then used for measuring the draft force. The encoder and the fifth wheel were also employed to measure the slippage. For measuring the fuel consumption, two flow meters were used in the round way. The profilometer was applied for measuring the soil upheaving and disturbance areas. The specific draft was also computed. The data analysis was performed by SAS software (9.4 edition). Multiple regression method was used for modeling the desired treatments.
Results and Discussion
The results of multivariate regression method for optimizing forward speed, tillage depth and tilt angle for the blades including winged were 3.3 km h^-1, 20 cm and 25°, respectively, and for the non-winged, 3.5 km h^-1, 20 cm and 24.8°. Providing the tilt angle on the blade surface is considered as an innovation in this research, therefore, it can be seen from the results that with increasing this angle, the draft of the tillage was decreased. This could be due to the increased surface of the blade in the face of the soil on the diagonal surface. This increase was proportional to the cosine tilt angle at the initial surface of the blade. Therefore, the shear strength of the soil was decreased with increasing of this surface and ultimately decreased the amount of draft of the tillage. This variable had a significant difference with the depth of tillage and the forward speed of tractor and fuel consumption for the winged new narrow blade. Although the interactions of the above mentioned variables on the fuel consumption for the new blade condition were not significantly different, the minimum fuel consumption for the non-winged blade condition was also obtained at the same tilt angle as the winged new blade. In general, considering all of factors, the 25 degree inclination angle was proposed for both conditions. The interaction of this factor (tilt angle) on the wheel slip rate was also significant. The effect of the angle of inclination for both blades was significant on the slip of the wheel drive, so that the increase in the tilt angle reduced the amount of wheel slip. However, if the amount of slip of the tractor's wheel for an optimum angle of 25° was considered, according to the graph which representing the relationship between tractive efficiency vs. wheel slip and for Cn = 50, the tractive efficiency will be determined by calculation. It should be noted that the tractor's tractive efficiency was equivalent to 82%. This value reflects the effect of the tilt angle on the amount of tractor output power according to the definition of the tractive efficiency of the tractor.
Conclusion
Considering the increasing growth of using combined tillage tools in dry soil and its low moisture content, and considering the necessity of replacing the custom chisel blades with new blades which resistance to the soil reaction forces upon them, the non- winged blades with the tilt angle about 25° for working depth of 20 cm and forward speed of 3.5 km h^-1 can increase the tractive efficiency of tractors to 82% and also decrease the fuel consumption by 34% compared to conventional tillage blades.

Abstract Introduction
One of the main factors affecting plant growth is soil compaction. More attention should be paid to soil compaction than the past. Soil compaction not only destroys the soil structure, but also leads to a heavier soil structure with natural cavities. The rolling resistance reduces energy and occurs when the tire moves on a soft soil and rolling resistance of the tire is brought about by two processes of soil deformation and wheel change. This force is influenced by the design of the tire, the parameters of the tire, and the characteristics of the soil. The apparent electrical conductivity (ECa) indicates the direct conductivity of direct current in the soil. The electrical conductivity is effective on chemical and physical properties, including the amount of soluble salts in the soil, salinity, cation exchange capacity, soil texture, organic matter content, moisture content and water holding capacity, and compression. The purpose of this study was to investigate the effect of soil compaction and soil moisture on the soil electrical conductivity and rolling resistance of the Messy Ferguson 285 tractor rear tire. This study showed the density and soil moisture were associated with soil electrical conductivity and rolling resistance.
 Materials and Methods
This test had independent and dependent variables. The dependent variables including rolling resistance and electrical conductivity, whose values were measured by a torque meter and a portable EC meter. Independent variable comprised of soil compaction and soil moisture measured by Penetrologger and soil moisture measurement tools including soil harvesting cylinder, scale and oven device. Experiments were carried out in the soil bin Laboratory with a 1.7 m wide, 24 m long and 1 m deep with soil texture of clay loamy in Agricultural Engineering Research Institute (Karaj). The soil was prepared layer by layer and up to a depth of 20 cm by the soil preparation unit. In all experiments, the vertical load was fixed at 4000 N and the tire pressure of 6899 N.m^-2. On each layer, the water was evenly sprayed to reach the desired moisture. To do this research, factorial experiment with soil compaction levels at 3 levels of 2, 4 and 6 roller passes, respectively, with the bulk density of 1.47, 1.54 and 1.69 g.cm^-3 and soil moisture at 3 levels of 10%, 12% and 14% were used in 3 replications. Data were analyzed using SPSS software. The tools used included the tire test rig, the rear tire of a Massy Ferguson 285 tractor, the soil preparation unit, and the measuring instrument, including the torque meter, the penetrologger and the portable EC meter.
 Results and Discussion
In this experiment, it was found that as the amount of moisture increased, the compaction was also increased. The test indicated that the soil rolling resistance was increased by decreasing the soil moisture content. Moreover, increasing in the soil compaction ration led to decreasing the soil rolling resistance. The CI was used at a depth of 20 cm to 0 cm. In these experiments, we concluded that the higher density of compaction resulted in increasing the soil cone index (CI). This index was directly related to the compaction, but it had an adverse relation with the moisture. It means the lower amount of moisture led to the higher amount of CI. The amount of electrical conductivity of soil was measured at a depth of 0-25 cm. In this experiment, we concluded that the higher compaction ratio resulted in the higher electrical conductivity. It means that electrical conductivity had a direct relation with the compaction and the moisture content. The lower moisture content led to the lower electrical conductivity of the soil.
 Conclusion
In general, considering all the tests and comparison between rolling resistance, soil cone index and apparent electrical conductivity before and after roller passing, it can be concluded that as the amount of moisture content increased, the soil cone index (CI) decreased. The soil cone index (CI) had a relationship with the moisture. The lower moisture content led to the lower soil moisture resistance, as well as the higher moisture content resulted in the higher soil resistance. The lower amount of soil compaction showed the greater soil rolling resistance, and the greater amount of soil compaction caused to the less soil moisture resistance. The electrical conductivity before and after the roller pass was different in the case of roller pass, and the higher amount of moisture led to the greater electrical conductivity, because the electrical conductivity was directly related to the moisture and the compaction affects all parameters.

Abstract The aim of this study is to design, fabricate and evaluate a new type of up-cut rotary tiller and to develop correct formulas to estimate its torque and draft force using the laws of classical mechanics. In order to verify the model, a real-sized prototype of the rotary tiller was tested. It was hypothesized that four processes are involved to create the rotary tiller torque, namely soil cutting, soil lifting, soil-metal friction, and soil velocity. Furthermore, it was assumed that the horizontal components of soil cutting and soil-metal friction forces create the required draft of the machine. Based on these hypothesizes, mathematical formulas were developed to calculate torque, and draft requirements of the machine. To facilitate performing necessary calculations, the developed formulas were entered in a worksheet of the MS Excel software. According to the results of this study, the average experimental draft and torque of the machine tilling a silty clay loam soil were 16.8 N and 12.8 Nm, respectively. Furthermore, the average theoretical draft and torque of the machine were 13 N and 11.8 Nm respectively. These promising results can be considered as the accuracy check of the formulas developed herein.

Abstract Harvesting is one of the most important field operations in sunflower production. Seed damage and low separation efficiency are the top concerns of harvesting sunflower. In this study, a threshing cylinder with rubber teeth and a concave for harvesting sunflower were designed and evaluated. The variable parameters were threshing cylinder speed (TCS), threshing space (TS) and moisture content (MC) of sunflower head. Azargol variety was used to evaluate the threshing unit. The tests were performed at three cylinder speed levels (280, 380 and 480 rpm), two threshing spaces (8 and 10 cm) and two moisture content of sunflower head based on the crop condition (20% and 45% wet basis). An ANN model was developed to predict the amount of materials in each part of the concave. Results showed that the sunflower seeds had no damage during the threshing process and the presented model could predict the amount of materials in each part of the concave with a regression coefficient R2=0.95. Based on the ANN model, with a decrease in MC and TS, and an increase in TCS, the separation efficiency was increased. Furthermore, optimal parameters for the threshing unit which were suggested by Design Expert software to maximize the separation efficiency were 18% w.b, 450 rpm and 10.5 cm for MC, TSC, and TS, respectively and in this condition separation efficiency was determined to be 94.92%.

Abstract Introduction
Harvesting is one of the most difficult steps in cabbage production that is usually a costly intensive operation. Cabbage harvesting is often done by human labors in Iran. According to customs administration’s statistics, more than 54000 tons of cabbages have been exported from Iran in 2015. Development of cabbage harvesting industry is necessary, because of the large cultivation area and the short available harvesting time. So far, a few studies have been done on cabbage mechanized harvesting in Iran. The harvesting machines can reduce harvesting time to one-eighth in comparison with manual harvesting. Design and manufacturing of a harvester unit suitable for small cabbage farms in Iran were conducted in the present study. So the paper was aimed to investigate the performance of the harvester at the different forward velocities, attack angles and distances between the plants.
Materials and Methods
The proposed machine consists of two major units; the soil looser and the unit for pulling out, crops from the soil. In this machine, the blades loose the soil around the cabbage root after penetrating into the soil. Next, cabbage is pulled out from the soil by puller belts. The belts move contrary to forward speed direction and take crop to the backward of the machine. Mechanical and physical properties of the cabbages should be measured, because the harvester is directly in touch with the crop. These properties are firstly measured and then selection of the different components and machine manufacturing are done. Two narrow legs (tillage tools) equipped with one-side blade with attack angles of 20 and 25 degrees are used for losing the soil around the cabbage’s root. The force exerted on the blade was 5.47 kN. Finally, the harvesting force is estimated to be 164.8 N by using mechanical and physical properties of the cabbages. Experiments were conducted at the different forward velocity levels (2, 3.5 and 5 km h^-1), attack angle of the blades at three levels (20, 25 and 30 degree) and the distance between the crops in two levels (40 and 60 cm) in a completely randomized design with three replications.
Results and Discussion
The analysis of variance of the effect of different parameters on the harvested crop numbers showed, that the effects of forward velocity and attack angle on the number of harvested crops were significant in 5 percent probability. But distance between crops did not have significant effect on the number of harvested crops. Also the effects of interaction between forward velocity and attack angle, forward velocity and distance between crops, attack angle and distance between crops on the number of harvested crops were significant in 5 percent probability. According to the results, the number of harvested crops and machine performance were decreased by increasing forward velocity. Moreover, designed machine had the best performance (80 percent) at an attack angle of 25 degrees and forward velocity of 2 km h^-1.
Conclusion
The results showed, with increasing the forward speed from 2 to 5 km h^-1 the harvest success decreased by 20 to 25 percent. Also, the harvesting quality did not change at the different distances between the plants. The highest machine capacity was more than 5300 plants per hour, which was observed at the forward velocity of 3.5 km h-1 and the attack angle of 25 degrees. 
 

Abstract Introduction
Nowadays, due to growth and development of the husbandry and its worthiness in providing human basic needs, affecting parameters such as costs, efficiency and fuel consumption is significantly important. So, increasing the efficiency of threshing machine could lead us to huge savings in energy. However using the conventional drums and concaves have some problems such as damaging  seeds due to impact, complicated manufacturing technology and spending a lot of energy in separating process. Therefore in order to overcome above mentioned problems especially energy consumption, a new seed pod husker based on rubbing was designed, fabricated and tested in this research.
Materials and Methods
Practical tests of this device were carried out on soybean which was harvested in a farm of Babolsar city. The experimental design was simple randomized complete design with three replications. The rotational speed of rollers and distance between rollers varied in three levels of 110, 170, and 210 rpm and 7, 8, and 9 mm for soybean.  The measured parameters consisted of efficiency, separation and loss. For designing the seed pod husker, the required electric motor power and the torque for separating seeds from its pods were calculated. After reviewing the physical and mechanical characteristic of some seed pod crops specially, soybean, a seed pod husker was designed in SOLIDWORKS 2013 software. In order to facilitate seeds separation from the pod, it was preferred to use the right-round and left-round Archimedes screw on the rollers. According to the preliminary evaluations, it was considered to use a speed range of 110 to 210 rpm; it was because of that the speed lower than 110 rpm was not able to open pods and the speed higher than 210 rpm caused hyper movements of pods. Analysis of variance (ANOVA) and mean comparisons and interaction between the parameters were performed using the SPSS 22 software.
Results and Discussion
The results indicated that the rollers were acceptable and sticking of pods were not seen. Results indicated that the efficiency of this device was increased with increasing the rotational speed and then was decreased. Increasing the rotational speed was led to increase separation. It is because of this fact that the performance of the husker’s component will be more powerful and crops suffer bigger impacts. The chart of device loss had a relatively upward slope. It could be due to a tougher collision between the seeds and the rollers. Increasing the roller distance, first decreased the efficiency of soybean and then increased that. The results indicated that separation efficiency decreased by increasing the distance. The reason for that was due to unavailable necessary force to separate the seed and pod. As the roller distance increased, the total losses of the device also increased. The reason for this was likely increasing in the movement of the seeds.
Conclusion
The results of practical tests and qualitative observations showed that the device had sufficient resistance against the maximum torque produced by the crop. Influence of rotational speed of rollers and rollers clearance on the efficiency, separation and loss were significant for new fabricated seed pod husker (p < 0.01). The capacity of the machine for soybean was 28.506 (kg hr^-1). To achieve maximum efficiency, maximum separation and minimum loss for soybean, authors suggest using (9mm-170rpm), (7mm-210rpm) and (9mm-110rpm) compounds, respectively. Eventually, it is suggested to evaluate this machine for other seed pod crops and for other parameters such as germination percentage, electric conductivity and ergonomic issues such as noise and machine vibration. Of course, it is recommended to survey the impact of length of husking roller, shaft rotation method and thread types on measurement parameters.        
 

Abstract Introduction
Tillage as a preliminary step for agricultural production consumes large amounts of energy. Regarding the energy crisis and the greenhouse gas emissions caused by the indiscriminate use of fossil fuels, many efforts have been done to reduce energy consumption as much as possible. About half of the energy used in the crop production has been dedicated to tillage operations; hence the optimization of tillage tools performance can lead to decrease the energy loss. Tillage operation in most regions of Iran is carried out by moldboard plow. The ability of this plow in turning the soil has made it impressively different from the other plows. The energy used in tillage operations depends on various factors such as soil type and its conditions (soil moisture and texture), plow depth and forward speed. The aim of this study is to investigate the effect of forward speed, plow depth and soil moisture on fuel consumption and required tensile force during tillage operation with a moldboard plow which uses three plows in clay soil.
Materials and Methods
The current study was carried out to optimize the tillage operation with a moldboard plow in the clay soil. Tillage experiments were performed to evaluate the effect of forward speed, plow depth and soil moisture content on the required tensile force and tractor fuel consumption. A moldboard plow with three single-sided plows was used to conduct experiments. Two tractors (MF285 and U650) and a dynamometer were used to measure the required tensile force. To measure the fuel consumption of the tractor during operation, the fuel level was measured in a separate tank system installed on the tractor's fuel system.
Experiments were carried out using response surface method and central composite design (CCD) by taking three levels of forward speed (4, 5 and 6 kmh^-1), three plow depth (20, 25 and 30 cm) and three levels of soil moisture content (12, 16 and 20%). Design Expert 8.0.6 software was used to analyze the experimental data.
Results and Discussion
The result of the analysis of variance showed that the effects of plow depth, forward speed and soil moisture, as well as the interaction between forward speed and moisture content on the fuel consumption during tillage operations with moldboard plow are significant. The results also indicated that the increase in forward speed decreased the fuel consumption. Also, fuel consumption decreased with increasing in moisture content at first, but then increased. The reason for this was probably because of the increased strength of soil particles due to the reduced moisture content (the stronger coherence force between the particles), which required more energy to shear the soil.
According to the results of analysis of variance, it can be concluded that all three factors of forward speed, plow depth and soil moisture had a significant effect on the required tensile force of moldboard plow at %1 probability level. With increasing the plow depth and forward speed, required tensile force increased significantly. The dependent variables were modeled as second order regression equations and optimal values of independent variables were determined. Optimum performance with maximum desirability was determined at forward speed of 5.08 kmh^-1, plow depth of 20 cm and soil moisture content of 16.41%.
Conclusion
With increasing plow depth, tensile force and fuel consumption increased. Also, tensile force increased with increasing forward speed, but this increase was not severely affected by the plow depth and reduced the fuel consumption. The quadratic regression models can well predict the required tensile force and fuel consumption. Using response surface method, optimum performance was determined at forward speed of 5.08 kmh^-1, plow depth of 20 cm and soil moisture content of 16.41%.