AbdolMajid Moinfar; Gholamhossein Shahgholi; Yousef Abbaspour-Gilandeh; Tarahom Mesri Gundoshmian
Abstract
The four-wheel drive and rear-wheel drive tractors are commonly used in agricultural operations. In order to investigate the effect of a type of driving system a series of tests were performed usin the three driving systems of foour wheel drive, rear wheel drive and front wheel drive in different axle ...
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The four-wheel drive and rear-wheel drive tractors are commonly used in agricultural operations. In order to investigate the effect of a type of driving system a series of tests were performed usin the three driving systems of foour wheel drive, rear wheel drive and front wheel drive in different axle loads of 0, 150 and 300 kg, tire inflation pressures of 170, 200 and 230 kPa and travel speeds of 1.26, 3.96 and 6.78 km/h. Bulk density was measured as an indicator of soil compaction at different depths of 10, 20, 30 and 40 cm. Also, under the different conditions, the drive wheel slip was measured. To carry out the tests, the four-wheel tractor of Goldoni 240 was used which has the ability to work with mentioned driving systems. The experiments were carried out under controlled conditions in a soil channel with the length of 3 m and a width and depth of 1 and 0.6 m, respectively. Test were conducted in completely randomised block design with three repetations and results were analysied using SPSS 22 software. The results showed that by changing the driving system from 4WD to RWD and FWD, there was a significant increase in soil density, with the lowest density associated with 4WD system and the highest density related to FWD. The reason for increasing the density by changing the driving system can be attributed to different slip levels in each of these systems due to the lower slip percentage of the 4WD system than the other two systems. Increasing axial load increased soil boulk density. Of note that with increasing the axial load, the stress was transferred from the surface soil to the subsoil layers. As the axial load on tire increases, the subsoil density was closer to the surface layer. Increased axial load on tire and decreasing tire pressure reduced wheel slip. Stepwise regression model with determination coefficient of 0.92 and according to calculated standard coefficients showed that axial load, soil depth, type of driving system, tractor speed, and finally tire pressure, have the greatest effect on soil bulk density, respectively.
Volume 21, Issue 74 , September 2020, , Pages 1-250
hooshang ardikhani; mohamad ghoamiparshokuhi; davood mohamadzamani; mohammad ghahdarijani
Abstract
Given the vastness of the country's border area and the climatic diversity of the crop and garden various regions, it is an undeniable necessity to achieve a suitable cultivation pattern that can maximize the utilization of factors and institutions of production, especially the water-limiting factor. ...
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Given the vastness of the country's border area and the climatic diversity of the crop and garden various regions, it is an undeniable necessity to achieve a suitable cultivation pattern that can maximize the utilization of factors and institutions of production, especially the water-limiting factor. The main question in this study is that considering the current situation in horticulture in Qazvin province, what parameters emphasize the optimal conditions for determining the cultivation pattern and allocating inputs in different orchards. For this purpose, in this study, first, the relevant technical, environmental, social and economic indices and criteria that have been presented in various research sources were examined. Then, using multi-criteria decision making methods, a composite index of the mentioned indices was presented. In this study, a simple two-step random sampling method was used. In this research, in order to present a suitable pattern for cultivating horticultural products from the ideal planning method using Lingo 17 software was used. According to the results of the model, in the case of phosphate and potash fertilizers, the consumption reduction was observed to be 9.5% (above the ideal level), but in the case of nitrogen fertilizer, the consumption was reduced by 8%. In the case of the three ideals of reducing the consumption of herbicides, insecticides and fungicides, excessive success was observed, i.e. a decrease in consumption of 4.5, 5.7 and 8 percent, respectively. Due to the abundance of water resources in this area, in the case of 12 ideals related to water reduction, too much success was observed, i.e. a one percent decrease in water consumption per month. The results show that the application of ideal planning method in optimizing goals and allocation for each product provides more logical results than single-objective models.
A. H. Ahmadbeyki; Mohammad Ghahderijani; A. M Borghaee; H. Bakhoda
Abstract
The increase in the area under greenhouse cultivation in Tehran Province is important for the increase in production and for its substantial social importance due to the preservation of agricultural land, especially small farms. In addition, the increase in the number of greenhouses producing summer ...
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The increase in the area under greenhouse cultivation in Tehran Province is important for the increase in production and for its substantial social importance due to the preservation of agricultural land, especially small farms. In addition, the increase in the number of greenhouses producing summer crops in this province attracts idle capital to the agriculture sector thereby creating jobs. The present research used stratified cluster sampling for selecting the counties of interest having the largest areas under greenhouse cultivation of summer crops in Tehran Province in order to select the producers in each greenhouse size range (taking into consideration the number of producers in it) via random sampling in which a table of random numbers was employed. Fifty-five greenhouses were selected in the province, 22 greenhouses producing only cucumbers, 15 greenhouses producing cucumbers and tomatoes, and 18 greenhouses producing cucumbers and bell peppers. The results of the cost-benefit analysis (CBA) showed that production of greenhouse summer crops was economically justified for greenhouses larger than 3000 m2 in surface area. However, the trend in the profitability of activities was a rising one for greenhouse surface areas of up to 4500 m2 beyond which a falling trend was observed. Finally, it was suggested that the Jihad Agricultural Organization of Tehran Province refuse to issue an establishment license for the production of greenhouse summer crops in areas lower than 1500 square meters and provide the necessary incentives for the production of greenhouse summer crops in Tehran, in areas between 5000 to 7500 square meters.
Farid Tamhidi; Morteza Almassi; Mohamad Ghahdarijani; Hossein Bakhoda
Abstract
Iran has special potentials in the field of medicinal plants, a field that have received less attention. The purpose of this study was to investigate the status of different stages of production of Rosa damascena and to select appropriate strategies for selecting and developing appropriate technology ...
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Iran has special potentials in the field of medicinal plants, a field that have received less attention. The purpose of this study was to investigate the status of different stages of production of Rosa damascena and to select appropriate strategies for selecting and developing appropriate technology in the country to lower the costs of production. The research method was descriptive-analytical. The method of collecting statistics and information required for the research was using a questionnaire and face-to-face interviews with farmers and experts producing and studying medicinal plants in three provinces: Isfahan, Kerman and Fars. The total number of questionnaires (Cochran method) in this study was 60. In this research, SWOT analysis model was used to investigate the mechanization situation in different stages of medicinal plant production Factors such as strength, weakness, opportunity and threat have been identified and analyzed in the matrix. Based on the research results, in the evaluation matrix of internal factors (weakness and strength), the sum of the final score was 2.75, which showed that the strengths were higher than the weaknesses. Also, the matrix of external factors (threat and opportunity) with a total score of 2.83 showed that in the current situation, it was possible to show an appropriate strategic response to threats by strengthening opportunities. Therefore, aggressive strategy (SO) was found the best strategy to move towards improving and developing mechanization in Rosa damascena farms in those provinces. Top strategies were also identified through quantitative strategic planning matrix or QSPM in offensive strategy.
Volume 16, Issue 65 , March 2016
Volume 17, Issue 66 , June 2016
Volume 17, Issue 67 , March 2017
Volume 18, Issue 68 , September 2017
Volume 18, Issue 69 , March 2018
Volume 19, Issue 70 , September 2018
Volume 19, Issue 71 , January 2019
Volume 20, Issue 72 , July 2019
Volume 20, Issue 73 , March 2020
Volume 21, Issue 75 , December 2020
Volume 21, Issue 76 , January 2021
Volume 22, Issue 77 , June 2021
Abstract
A major problem in olive production is picking the fruit from the trees. The cost of traditional harvesting of olives forms over half the cost of production. Selection of the appropriate method of olive harvesting depends on the planting system, orchard topography, labor, social, and economic factors, ...
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A major problem in olive production is picking the fruit from the trees. The cost of traditional harvesting of olives forms over half the cost of production. Selection of the appropriate method of olive harvesting depends on the planting system, orchard topography, labor, social, and economic factors, as well as the variety and size of trees. The present study compared mechanical harvesting of the Zard variety in Qazvin province and Local variety in Guilan province using four types of harvesting machine. These were the tractor mounted branch shaker, hand-held branch shaker, hand-held pneumatic comb, and electrical rotating comb. Two maturity indices (MI) were tested (3.5 = early time and 4.5 = suitable time). Machine performance parameters were percentage of fruit removed, mechanical and hand harvesting time, worker productivity, and damage to trees by mechanical harvester. The results showed that the effect of MI on the percentage of fruit removed for the Zard variety was significant (probably level = 1%), but not for the Local variety. Machine type had a significant effect (probably level = 1%) on all performance parameters. Worker productivity for harvesting of the Zard variety was 130.72 kg/h for the tractor-mounted branch shaker, 93.36 kg/h for the hand-held branch shaker, 50.73 kg/h for the pneumatic vibrating comb, 40.57 kg/h for the electrical rotating comb, and 22.15 kg/h for the traditional method. The corresponding values for the Local variety were 96.28, 57.97, 22.43, 23.24, 12.5 kg/h, respectively.
Majid Lashgari; Reza Mohammadigol
Abstract
Eggshell crack detection in grading lines is very important. In recent years, various methods have been studied for this purpose. One of the conventional methods used in the eggshell crack detection is acoustic response. With this method, types of cracks which are apparent defects by analyzing the acoustic ...
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Eggshell crack detection in grading lines is very important. In recent years, various methods have been studied for this purpose. One of the conventional methods used in the eggshell crack detection is acoustic response. With this method, types of cracks which are apparent defects by analyzing the acoustic response to mechanical impact will be recognizable. In this research, the effects of factors related to acoustic system such as ball material, impact angle and microphone position on acoustic response in detection of cracks types were investigated. Accordingly, factorial experiments in a completely randomized design with three replications were performed. The results showed that levels of ball material, impact angle and microphone position and cracks types had significant effects (P<0.01) on the first three amplitudes and frequencies. Also, the results of this study showed that the use of plastic balls at the hitting angle of 45 degrees and positioning of microphone at the angle of 180 degrees is more suitable in designing of acoustic system to detect eggshell cracks.
Ardeshir Asadi; Orang Taki
Abstract
Soil aeration by imported machines were reportedly unsatisfactory due to creation of shallow holes, taking off some patches of the turf and time consuming work needed for collecting the excavated cores. Considering these problems, a machine was developed to suit Iran’s lawn spaces. To develop an ...
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Soil aeration by imported machines were reportedly unsatisfactory due to creation of shallow holes, taking off some patches of the turf and time consuming work needed for collecting the excavated cores. Considering these problems, a machine was developed to suit Iran’s lawn spaces. To develop an appropriate aerator, the shape of the plugs was studied at the first step and for this purpose six types of plugs with conical and cylindrical cross section (with and without slot) with tips cut diagonally and perpendicularly were built. The plugs were compared in an experiment based on complete randomized blocks design with 3 replication in an urban lawn space with clay soil in terms of the required static force for cutting the thatch and penetrating to the soil as well as the length of out coming cores. The results showed that the conical plugs with beveled tips had a 28 millimeter longer cores than the cylindrical plugs with similar tip using approximately equal forces for insertion. Having chosen the appropriate shape of plug, a split roller with a relatively large diameter were constructed for installing plugs around it and the whole device attached to a walking tractor. Comparing the developed machine with a commercial self-propelled aerator revealed that the developed aerator improved the length of the cores and depth of the holes. The split roller in the machine which windrowed the cores also caused a 65% decrease in labor requirement for collecting the cores and did not have dug patches of turf.
Abstract
Composting livestock manure and municipal solid waste is an appropriate method for waste management in order to stabilize organic wastes. The low specific mass of compost causes problems in transportion and storage activities and increases the costs. In this study some parameters affecting the pellets ...
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Composting livestock manure and municipal solid waste is an appropriate method for waste management in order to stabilize organic wastes. The low specific mass of compost causes problems in transportion and storage activities and increases the costs. In this study some parameters affecting the pellets production was investigated. Parameters considered were: particle size (1 and 2 millimeter), pellet moisture content (25, 35 and 45 percent) and kneading length (1, 2 and 3 meter). Results showed that the specific density of pellets produced under both levels of particle size, increased with increasing the Length of kneading at all levels. Interaction effect of moisture content and kneading length on the rate of fractured pellets showed that, the maximum amount of force was (556.32N) which belonged to treatment with (moisture content of 35% and length of kneading of 3 m). Also the interaction effect of particle density and length of kneading showed that maximum toughness value was (1.03 MJ/m3) which belonged to particle density of 1mm and kneading length 3 m.
Ali Nejat Lorestani; Mohamad Younesi-Alamouti
Abstract
Researche results indicates that 20 to 55 percent of the available tractor energy is wasted at the traction /soil interface, because of soft agricultural soils, tire tread for traction plays a major role. Using computer simulations to study the interaction between tire and soil, the number of physical ...
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Researche results indicates that 20 to 55 percent of the available tractor energy is wasted at the traction /soil interface, because of soft agricultural soils, tire tread for traction plays a major role. Using computer simulations to study the interaction between tire and soil, the number of physical tests and development costs can be greatly reduced. Finite element simulation of complex systems is a very effective way for investigation as is used in the soil bin tire test. In this investigation experiments were conducted for tires without tire tread, the tire tread at an angle less than the angle of the tread on the tires with full tread design, the tire tread wider than the width of the tread of the tire with full tread design, the tire tread longer (greater height) than the height of the tire tread with full tread design and tread of the tire with greater distance (distance between the step tread) than the distance in tire with complete tread design. The simulation results showed that a in absence of tread on the tire traction and the linear velocity was reduced. Also as the tire tread angle with regards to axle decreased the traction increased. But resulted in variable and oscillation under variable linear velocity condition. Furtur an increase in the width of the tread reduced the amount of traction and an increase in the height of tread increased the traction force, but caused a oscillatory and variable linear velocity. Finally an increase in the distance between two treads caused oscillatory and variable traction force and linear velocity.
Sajad Sabzi; Yousef Abbaspour-Gilande; Hosein Javadikia
Abstract
The weeds must be removed from the field due to their competition with principal crops to use water, nutrients, sunlight, etc. There are different methods to remove the weeds: mechanically, manually or chemically (applying herbicides). For farmers, applying herbicides is a usual way, but brings some ...
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The weeds must be removed from the field due to their competition with principal crops to use water, nutrients, sunlight, etc. There are different methods to remove the weeds: mechanically, manually or chemically (applying herbicides). For farmers, applying herbicides is a usual way, but brings some concerns, from the point of environmental issues, due to equal application of chemicals all over fields, regardless the presence or absence of weed. For this reason, a machine vision system based on video processing was proposed to recognize Secale cereale L. (as a weed) from potato plant (as principal crop) to make herbicide application more accurate. Nine hundred sixty five objects were recognized after taking videos, pre-processing and segmentation. Fourteen features were extracted from each object. Using the hybrid artificial neural network-genetic algorithm, of 14 extracting features, only 6 features were selected as effective ones: average, the third moment, autocorrelation, correlation, dissimilarity, and entropy. Data were classified into two groups: training data (70% of the total data) and testing data (30% of the total data). The classification was performed using hybrid of artificial neural network - Bio-geography Based Optimization (BBO) algorithm. Performance of classification system was evaluated through analysis of confusion matrix and Receiver Operating Characteristic (ROC). Sensitivity, specificity, and accuracy were calculated using confusion matrix. The results showed that the sensitivity, accuracy and specificity of classification system reached to an acceptable level: 99.49 %, 99.65% and 98.91%, respectively. Our conclusion is that it is possible to manufacture the machine vision system with mentioned aims that work as online.
Yousef Abbaspour-Gilandeh; Fereshteh Hasankhani; Gh. Shahgholi
Abstract
Design of agricultural machinery and implements for local needs, requires determination of accurate values of physical and mechanical properties of soil, including soil-metal friction coefficient. In this study, the effects of soil moisture content at five levels and sliding speed (at three levels of ...
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Design of agricultural machinery and implements for local needs, requires determination of accurate values of physical and mechanical properties of soil, including soil-metal friction coefficient. In this study, the effects of soil moisture content at five levels and sliding speed (at three levels of 0.5, 2.5 and 3.5) on four contact materials namely: steel, cast iron, rubber, and Teflon on the soil- metal external coefficient of friction of of loam, sandy loam and loamy sand soil at 5 levels of soil moisture content was investigated In this context a device was designed and evaluated for accurate determination of soil friction coefficient. Data were analyzed based on 5×4×3 factorial experiment in randomized complete block design using MSTATC software. Due to differences in moisture content at different phases of friction, adhesion and fluid in soils with different textures, statistical analysis was performed separately for each soil texture and nested factorial design was used to study the effects of soil texture. Results showed that in all soil types, three sliding speed levels affected soil-metal friction significantly at the probability level of 1%. Also, with increasing sliding speed, soil-metal friction coefficient had incremental trend. Meanwhile, the results also showed that at the experimental sliding speeds of 0.5, 2.5 and 3.5 cm/s, the trend and pattern of the curves of soil friction coefficient versus soil moisture content were similar. Results of this study and the determined values of parameters of soil-metal friction coefficient and adhesion could be used in the design of agricultural machinery and implements, modeling of the relationship between soil & machine, draft calculation and also in tillage implements performance and their wear and tear investigations.
Payam Farhadi; Abdollah Golmohammadi; Ahmad Sharifi-Malvajerdi; Gholamhossein Shahgholi
Abstract
In this study, a single tire tester was used to study the effects of vertical load, inflation pressure and moisture content on tire rolling resistance in a soil bin. A Goodyear 12.4-28, 6 ply tractor drive tire was employed and the soil texture was a clay loam. The experimental design was a completely ...
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In this study, a single tire tester was used to study the effects of vertical load, inflation pressure and moisture content on tire rolling resistance in a soil bin. A Goodyear 12.4-28, 6 ply tractor drive tire was employed and the soil texture was a clay loam. The experimental design was a completely randomized with factorial layout at three replications. A multivariate regression model was obtained with the correlation coefficient of R2=0.85 to predict the tire rolling resistance based on vertical load, inflation pressure, and moisture content. A multilayer feed-forward ANN (artificial neural network) with standard BP (back propagation) algorithm and LM (Levenberg-Marquardt) training function by using of two hidden layer in the network architecture was employed. RMSE (root mean squared error) and R2 was used as modeling performance criteria. Tire inflation pressure was identified as the controller parameter of tire rolling resistance at low moisture content and also moisture content was the most effective parameter on changing of rolling resistance in regression model. Also the obtained R2=0.977 from ANN model showed that ANN data were more close to actual data than the regression model.
