Papers by Yousef Abbaspour-Gilandeh
Applied Mechanics …, Jan 1, 2012
In many parts of the world, row crops are treated with herbicides. Because of environmental conce... more In many parts of the world, row crops are treated with herbicides. Because of environmental concerns, crop cultivation is suggested as an excellent method of weed control. The object of this study was to design and construct a high speed inter-row cultivator. The speed of plowing has a significant effect not only on the depth of plowing but on factors which affect the quality of soil preparation such as loosening of the upper soil layer, cutting roots of the previous crops, covering and plowing in of weeds, leveling the finished surface of the field, displacement of the son layer and so on. In this study, the designed and constructed cultivator has a toolbar, unit frame, disk coulter and a flat sweep. The unit frame is attached to a tractor mounted tool bar by a suspension linkage. The suspension linkage allows the unit frame to move up and down relative to a tool bar that the cultivator unit is attached to. The numerical analysis was performed with COSMOS/M 1.71 FEM software (Structural Research and Analysis Corporation, CA).
Measurement, Jan 1, 2012
Soil compaction is the basis of determining the tillage depth in the precision tillage system. Th... more Soil compaction is the basis of determining the tillage depth in the precision tillage system. The objective of this study was to compare the performance of two prototypes of measuring systems for horizontally on-the-go soil mechanical resistance measurement including: a vertical single blade equipped with four miniature load cells and a multiple blades system with four independent sensing blades equipped with precision measuring implements and octagonal ring transducers. Results showed that the multiple probes sensor represented closer data to cone penetrometer with correlation coefficient of 0.63, 0.84, 0.83 and 0.80 for the depth of 0-10, 10-20, 20-30 and 30-40 cm, respectively. While these values were 0.23, 0.16, 0.51 and 0.69 for single blade sensor. Some other advantages of multiple blade probes were lower disturbance in the soil, representation of the same failure mode to cone penetrometer at deeper depths, and lower fluctuations in measured data.
Measurement, Jan 1, 2011
Predicting tractor fuel consumption can lead to selection of the best conservation practices for ... more Predicting tractor fuel consumption can lead to selection of the best conservation practices for farm equipments. In present study for estimating tractor fuel consumption was used from the Nebraska Tractor Test Lab (NTTL) data. Fuel consumption was assumed to be a function of engine speed, throttle and load conditions, chassis type, total tested weight, drawbar and PTO power. Back propagation Artificial Neural Network (ANN) models with six training algorithms were adopted for predicting fuel consumption. The highest performance was obtained for the network with two hidden layers each having 10 neurons which employed Levenberg-Marquardt training algorithm. Results indicated that the ANN and stepwise regression models represented similar determination coefficient (R 2 = 0.986 and R 2 = 0.973, respectively) while the ANN provided relatively better prediction accuracy (R 2 = 0.938) compared to stepwise regression (R 2 = 0.910). One of the advantages of ANN model was integration of load and throttle condition in the form of one model.
Instruments and …, Jan 1, 2011
Abstract The extended octagonal ring transducers are popular devices for force and moment measure... more Abstract The extended octagonal ring transducers are popular devices for force and moment measurements in agricultural engineering research due to its capability in measuring forces independently in two dimensions and resultant moment in one dimension. In this study ...
… -Eurasian Journal of …, Jan 1, 2007
Soil compaction management in the southeastern Coastal Plain soils relies heavily on the use of c... more Soil compaction management in the southeastern Coastal Plain soils relies heavily on the use of costly annual deep tillage operations. Variable-depth or site-specific tillage which modifies the physical properties of soil only where the tillage is needed for crop growth, has potential to reduce costs, labor, fuel and energy requirements. Although technology for site-specific tillage is available, there is very limited information on the fuel and energy requirements of site-specific tillage in southeastern coastal plain soils. Tests were carried out on three different coastal plain soils to compare energy requirement of site-specific tillage with uniformdepth tillage operations. Also, the effects of tractor speed, soil texture, moisture contents and electrical conductivity on energy requirement and fuel consumption were determined. The energy saving of 50% and fuel saving of 30% were achieved by site-specific tillage as compared to uniform-depth tillage in a loamy sand soil type. Although draft force increased with an increase in travel speed in all soil types but the tillage depth had bigger effect on the draft and drawbar power than the tractor speed. The effect of soil moisture content on draft force and fuel consumption was not significant in loamy sand and sandy loam soil types. Soil EC was highly correlated to soil texture (R =0.916) and draft force across the field. 2 Key words: Tillage energy % precision agriculture % site-specific tillage % tractor speed % soil moisture % electrical conductivity
International journal of …, Jan 1, 2009
Development and application of Artificial Neural Network (ANN) in modeling of the physical and dy... more Development and application of Artificial Neural Network (ANN) in modeling of the physical and dynamical soil properties and study of the possible relation of this technique with finite element method now a day is increasing. It is expected the success of ANN application particularly in simulating the operation of tillage practices and dynamic behavior of agricultural soil. One of the reasons in which leads us to use this method is its powerful estimation and the other one is that there is no specific material relation between the dependent and independent variables. In this research, parameters such as travel speed, tillage depth and other soil parameters such as cone index, moisture content, electrical conductivity and percentage of clay and sand are used to develop a prediction model. Experiments were conducted on three different types of coastal plain soils in the south eastern of United States for collection of required data. The model designed in this study was a multilayer network back propagation. Three algorithms of gradient descent with momentum, Lavenberg-Marquardt and scaled conjugated gradient algorithm were used to train the network. The best algorithm, used to train the network was chosen based on the high accuracy of prediction (95.8%) and more accurate simulation (97.6%), was the Lavenberg-Marquardt algorithm which recognized as the best algorithm (with two mean layers which include 12 neurons in the second layer) in comparison with other algorithms. The obtained scatter charts showed a correlation coefficient (R 2 ) of 0.996 in network training and correlation coefficient of 0.987 in network testing between actual data and obtained data from ANN. Also these ANN models were compared with regression models based on data presented by ASAE and Garner's model to evaluate the model. The comparison of the results of model and regression models to predict the draft force needed in subsoiling showed that ANN data are more close to actual data than the regression models.
International journal of food, agriculture and …, Jan 1, 2009
Soil compaction limits root penetration below the plowing depth, reduces yields and makes plants ... more Soil compaction limits root penetration below the plowing depth, reduces yields and makes plants more susceptible to drought stress. Applying uniform-depth tillage over the entire field to manage the soil compaction may be either too shallow or too deep and it can be costly. Variable-depth or site-specific tillage technology optimizes soil physical properties only where the tillage is needed by applying tillage at the required depth. Therefore, there is a need for a technology to determine the tillage depth based on soil mechanical strength at different depths of soil. Since soil cone penetrometers require a stop-and-go operation that can be time-consuming and costly, on-the-go measurement methods of soil mechanical strength have been investigated by some researchers. A measuring system with multiple instrumented shanks was designed and built to measure mechanical impedance of soil at different depths over the entire top 40 cm of the soil profile while moving through the soil. This system allows shanks for the simultaneous measurement of soil mechanical resistance at four depths, while moving through the field. The design allowed 10 cm of measurement depth per instrumented shank. Each instrumented shank consisted of an extended octagonal load cells. Each shank was calibrated in the lab by applying known forces and measuring output voltages. DT800 data logger (data Taker Co., UK) was used for data collection. Soil strength data was collected at 150 Hz. The instrumented measurement system was calibrated against cone penetrometer readings at same depth intervals by collecting intensive geo-referenced penetrometer data from a predetermined path and then running instrumented system with multiple shanks in the same path. The penetrometer data was averaged over 10 cm intervals and compared to the average force measurements from each instrumented shank of measurement system. There was a correlation with R 2 = 0.77 (the least correlation coefficient) at 0-10 cm depth and R 2 = 0.83 (the most correlation coefficient) at 30-40 cm depth between soil cone penetrometer data and instrumented measurement system values.
American Journal of …, Jan 1, 2009
American Journal of …, Jan 1, 2009
Problem statement: Soil fragmentation is a primary aim in tillage in order to create a favorable ... more Problem statement: Soil fragmentation is a primary aim in tillage in order to create a favorable soil environment for crop growth. Soil fragmentation is defined as the process of breakdown and crumbling of soil aggregates. Currently, there is no published research data on optimum tillage operations for seedbed preparation in loamy-clay soils of western Caspian Sea region of Iran. Approach: Tests were conducted on a loamy-clay soil near the city of Ardabil, Iran, to investigate the effects of different tillage operations on soil crumbling. Four tillage treatments: Moldboard plow (M) (conventional method), Moldboard plow and Disk-Harrow (MH), Decompactor and Moldboard plow (DM) and De-Compactor and Disk-Harrow (DH) were used in this study with four replications. The tillage depth for all treatments was about 30 cm. Following tillage operations, intensive soil samples were taken from the top 25 cm of soil at 5 cm depth increments and were analyzed for aggregate size and distribution using 9 standard sieves (0.25-19 mm mesh). Analysis of variance was carried out regarding soil crumbling percentage and mean diameter of soil aggregates in each treatment. The experiment was arranged in a split-plot design with five levels of soil sampling depths and two main factors (tillage method and tillage depth) which were arranged in Latin Square design. Results: Results showed that the tillage treatments had a significant effect on soil crumbling. Also, soil crumbling varied with soil depth and the optimum particle sizes were developed at the 5-20 cm soil depth. There was a non-linear correlation between soil crumbling percentage and tillage depth. Conclusion/Recommendations: Tillage methods and soil sampling depth had interaction effect on soil crumbling percentage. The MH treatment had the greatest amount of soil crumbling and the best seed-bed condition.
Int. J. Agric. …, Jan 1, 2006
Most sandy soils of the Southeastern Coastal Plain of U.S.A. have a compact layer that requires a... more Most sandy soils of the Southeastern Coastal Plain of U.S.A. have a compact layer that requires alleviation by costly annual deep tillage operations. Site-specific variable-depth tillage, which modifies soil physical properties to the specific depth of compacted layer has potential to reduce costs, labor, fuel and energy requirements. Although technology for site-specific tillage is available, there is very limited information on the fuel and energy of site-specific tillage in southeastern coastal plain soils. Tests were conducted on three different coastal plain soils to compare energy requirement of site-specific tillage compared to conventional uniform-depth tillage operations. Also, the effects of tractor speed, soil texture, moisture contents, and electrical conductivity on energy requirement and fuel consumption were determined. The energy and fuel saving to 50% and 30%, respectively were achieved by site-specific variable-depth tillage as compared to conventional uniform-depth tillage in a loamy sand soil type. The draft force increased as the travel speed increased in all soil types. However, the tillage depth had the greatest effect on the draft and drawbar power than the tractor speed. The effect of soil moisture content on draft force and fuel consumption was no significant in loamy sand and sandy loam soil types. However, draft force and fuel consumption had a negative correlation with the soil moisture contents. Soil EC was highly correlated to soil texture (R 2 = 0.916) and draft force across the field.
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Papers by Yousef Abbaspour-Gilandeh