Original Article
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.
Original Article
Abstract
The present study evaluated the performance of a novel solar heating system. A linear Fresnel lens was used to concentrate the heat in this system. Pre-experimentation tested the performance of the system at 5 alignment angles and 5 slope angles. The data was used to evaluate the performance of the system ...
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The present study evaluated the performance of a novel solar heating system. A linear Fresnel lens was used to concentrate the heat in this system. Pre-experimentation tested the performance of the system at 5 alignment angles and 5 slope angles. The data was used to evaluate the performance of the system in December 2014 at 6 flow rates (100, 200, 300, 400, 600, and 800 ml.min-1). In these experiments, solar radiation, wind velocity, temperature of fluid in collector, ambient temperature, and ambient relative humidity were recorded. The results demonstrated that the best performance of the system was at a 300 ml.min-1 flow rate, due south orientation, and with monthly adjustment of the slope of the lens. The correlation between the parameters indicated that at different flow rates, the effect of solar radiation on the temperature of the ambient air, heat-absorber pipe, output fluid, and input fluid were 0.91, 0.895, 0.86 and 0.84, respectively.
Original Article
Abstract
This study was conducted to achieve effective and low-cost technology for non-destructive grading of unshelled almonds in real time. A laboratory prototype of an intelligent online impact-acoustic system composed of a feeding unit, acoustical recognition unit, and pneumatic separator with an electronic ...
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This study was conducted to achieve effective and low-cost technology for non-destructive grading of unshelled almonds in real time. A laboratory prototype of an intelligent online impact-acoustic system composed of a feeding unit, acoustical recognition unit, and pneumatic separator with an electronic controller unit was constructed and tested. To evaluate system operation according to almond variety and class (hard, semi-soft, and soft), the effect of an acoustic signal generated by dropping the nuts onto a steel plate was captured by microphone and the amplitude, phase, and power spectral density were extracted from analysis of the sound signal in the time and frequency domains by means of fast Fourier transform. A multilayer perceptron neural network with a LM training function were used in all experiments. The classification accuracy using validation data was about 96.2% in the offline mode, but accuracy decreased to 88% in the online mode. This decrease in accuracy was probably the result of a difference in size and mass of the almond samples in the hard and semi-soft classes.
Original Article
Abstract
The current study developed and tested machine vision and automatic control systems to improve performance and reduce rice loss during paddy husking. This system was optimally adjusted for paddy type, moisture content of paddy, roller spacing and rotational speed of the motor. The percentage of breakage ...
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The current study developed and tested machine vision and automatic control systems to improve performance and reduce rice loss during paddy husking. This system was optimally adjusted for paddy type, moisture content of paddy, roller spacing and rotational speed of the motor. The percentage of breakage of rice kernels was determined using a machine vision system and a singulation device. If rice breakage was greater than a set point, the husker device was adjusted as necessary. The variables of paddy moisture content, roller spacing, and motor rotational speed were used to determine the working conditions of the husker for two paddy varieties. The dependent variables were husking index and rice kernel breakage percentage. An image processing algorithm was coded and evaluated in MATLAB software to determine the percentage of rice kernel breakage. The results showed that selection of proper treatment for the medium-sized kernel paddy, the average husking index was 82.65% and the average rice breakage was 3.88%. For the long kernel paddy, the average husking index and rice breakage were 51.4% and 27.46%, respectively. Without use of the system and with improper selection of motor rotational speed and roller spacing in the medium-sized kernel paddy produced a husking index of 61.58% and rice breakage of 7.51%. For the long kernel paddy, the husking index was 19.14% and rice breakage was 35.03%. Results from the algorithm showed that its accuracy was 91.81%. Evaluation of the singulation device showed that a suction of -45 to -50 mmHg yielded an appropriate 81.3% separation efficiency. The best combination of the machine parameter levels were programmed into the system, which operated to make the proper adjustments automatically. This resulted in the most appropriate working conditions for husking in accordance with paddy variety, paddy moisture content, roller spacing, and motor rotational speed.
Original Article
Mohamad Mazhari
Abstract
Iranian saffron is produced mainly in the provinces of Khorasan-e Razavi and Khorasan-e Jonoobi and is a strategic product of the agricultural sector. The high demand in the global market for saffron provides employment opportunities. Increasing production by improving mechanization methods at the various ...
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Iranian saffron is produced mainly in the provinces of Khorasan-e Razavi and Khorasan-e Jonoobi and is a strategic product of the agricultural sector. The high demand in the global market for saffron provides employment opportunities. Increasing production by improving mechanization methods at the various stages of production is the major challenge. The research format of this study was applied-development and the method was a cross-sectional survey. The SWOT model of strategic planning was the most important model for determining the strengths, weaknesses, opportunities, and threats of mechanization in saffron production. These were identified and evaluated and the best strategy for the development of mechanization was determined. The results showed that the sum of the final scores of the internal matrix factors (strengths and weaknesses) was 2.73. This indicates that the strengths were greater than the weaknesses. The matrix of external factors (opportunities and threats) had a total score of 2.67, which indicates that the current situation can be strengthened in the face of threats and opportunities with an appropriate strategic response. An aggressive strategy is best for improvement and development of farm mechanization in the Khorasan provinces. The superior strategies were determined using the quantitative strategic planning matrix (QSPM).
Original Article
davood mohammadzamani
Abstract
The present study designed, constructed, and evaluated a fully-automatic tomato transplanter. In this device, a step mechanism gradually guides the tray to the left, right, and down under the arm so that the pin lifter can be position to penetrate the soil in the cell to grasp a seedling. The arm then ...
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The present study designed, constructed, and evaluated a fully-automatic tomato transplanter. In this device, a step mechanism gradually guides the tray to the left, right, and down under the arm so that the pin lifter can be position to penetrate the soil in the cell to grasp a seedling. The arm then positions itself over the tube and releases the seedling in its soil pot. The seedling falls into the previously plowed furrow. To evaluate operation of the machine, field testing was conducted. Mechanical damage to seedlings, seedling establishment angle according to the vertical line, and seedling spacing on the row was investigated. Tests used a factorial randomized complete block design with three replications. The treatments consisted of traveling speed (1, 1.5, and 2 kmh-1) and depth (5 and 10 cm). In each experimental unit of the block, the machine traveled the 22 m length to plant one row. Results showed that traveling speed, depth, and the interaction of distance between planted seedlings, seedling establishment angle, and mechanical damage to seedling was significant. Results indicated that the most appropriate traveling speed was 1 kmh-1 and depth of planting was 5 cm. With a traveling speed of 1 kmh-1, a theoretical capacity of 0.06 hah-1 was determined for the single-row machine.
Original Article
Abstract
One way to recycle crop residue and animal manure is the production of biogas by anaerobic digestion. The present study evaluated and compared the extraction of biogas from residual canola straw,cattle manure and rumen contents. Reactors, mixers, and a hot water bath were designed and manufactured to ...
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One way to recycle crop residue and animal manure is the production of biogas by anaerobic digestion. The present study evaluated and compared the extraction of biogas from residual canola straw,cattle manure and rumen contents. Reactors, mixers, and a hot water bath were designed and manufactured to compare the extraction of biogas from these resources. Substrates were cast into the reactors after mechanical and thermal pretreatment to determine the percentage of carbon to nitrogen and the total and volatile solids. The treatments included: (1) residue of canola straw + manure + rumen contents, (2) manure, and (3) rumen contents. The treatments were compared in a completely randomized design with three replications in one-liter reactors. The results showed that the experimental treatment factors of biogas production, percentage of methane, accumulated methane, and decrease in total solids showed significant differences. Treatment (1) fell into group A with 504.1 l/kg VS of biogas produced and accumulated methane of 277.9 l/kg VS. Treatment (2) fell into group B with 178.6 l/kg VS of biogas produced and accumulated methane of 116.5 l/kg VS. Treatment 3 fell into group C with 14.8 l/kg VS of biogas produced and accumulated methane of 4 l/kg VS. The percentage of methane in groups A and B was 55% and 60%, respectively. The percentage of decrease in total solids in treatments (1) and (2) was 59% and 46%, respectively. There were no significant differences between groups B and C for ratio of carbon to nitrogen. The results indicate that fresh cattle manure + rumen contents in combination with canola residue produced the highest accumulated methane and use of this combination is recommended.
Original Article
Abstract
The current research investigated the draft force, soil disturbance area, specific draft, tractor fuel consumption, slippage of drive wheels, drawbar power, traction efficiency, and overall energy efficiency of subsoiling. The effects of forward speed (1.8, 2.3, 2.9 and 3.5 km/h) and depth (40 ...
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The current research investigated the draft force, soil disturbance area, specific draft, tractor fuel consumption, slippage of drive wheels, drawbar power, traction efficiency, and overall energy efficiency of subsoiling. The effects of forward speed (1.8, 2.3, 2.9 and 3.5 km/h) and depth (40 and 50 cm) on these parameters were evaluated using a randomized complete block design. An increase in forward speed increased draft force by 7%, specific draft by 15.4%, fuel consumption by 10%, wheel slippage by 2.9%, drawbar power by 108.3%, and overall energy efficiency by 6% and decreased soil disturbance area by 7.2% and traction efficiency 10%. Increasing the subsoiling depth increased the draft force by 21.3%, soil disturbance area by 25.6%, fuel consumption by 39.6%, wheel slippage by 2.8%, and drawbar power by 21.4% and decreased specific draft by 3.4%, traction efficiency by 6.7%, and overall energy efficiency by 1.4%. The most efficient operating settings were a working depth of 40 cm with a forward speed of 2.9 km/h.
