Iranian Journal of Biosystems Engineering
Year:2018 | Volume:49 | Issue:2 |Papers Count:16

With the development of modern drying paddy in addition to speed up the drying process, and in particular the amount of waste can be reduced to the minimum possible energy consumption. In this study was investigate the effect of input air temperature, input air flow rate and variety also their interaction on energy consumption and drying rate in the fluidized bed dryer. The parameters of input air temperature at 4 levels of 45, 50, 55 and 60 ° C, the air flow rate at 3 levels of 0/12, 0/14 and 0/16 m3/s and variety of paddy at 3 levels Tarom, Fajr and Shirudi was considered and tests was done in three replication in form of a 3×3×4 the 3-factor factorial design. The results indicated that In all three varieties tested, by increasing the intake air temperature as well as reduced energy consumption, drying rate also increased significantly. At 45 and 50 ° C, increasing air flow grain drying had no significant effect on the rate But at 55 and 60 ° C by increasing the flow rate of drying significantly increased. The results showed that by increasing air flow, increased energy consumption.

This research has focused on study of changing static and dynamic pressure and velocity values in three levels of different bio filter cross sections. The studied factors included gas flow rate, cross sectional area (trapezoidal, square and circular), vertical position (bed center line, front line and rear end) in four elevation ranges from the bottom of the bio filter bed (the first part 0 to 16. 75 cm, the second part 16. 75 to 29. 25 cm, the third part 29. 25 to 41. 75 cm and the fourth part was 41. 75 to 58. 5 cm) was examined. The results of studying the pressure and velocity in the three cross sections showed the lowest mean of dynamic and static pressure in the square section and the mean speed was higher due to the absence of the corner at the cross section. The variations of pressure in different ranges of bio filter bed showed a decreasing trend, so that the average of dynamic pressure drop and static pressure drop in these ranges were 87. 9 and 44. 4%, respectively. While the maximum dynamic pressure has obtained from circle section. At the locations assumed in this study, the maximum average of dynamic pressure estimated 1. 509×10-5 Pa at center line. For the other locations the average dynamic pressure obtained 2. 502×10-6 Pa at front line and 2. 481×10-6 Pa at back line.

Interaction between soil and machine is essential challenge for researchers, developers, designers and manufacturers of agricultural machineries. Modeling of tillage equipment is an important Engineering work. However, interaction modeling is a complex process due to three-dimensional changes in soil, nonlinear soil behavior phenomenon and soil flow quality in connection area between the soil and tool and the dynamic effects of equipment. Correct simulation of the interaction of soil is the key point for the optimization of tillage tools and can eliminate required field tests with high costs. The purpose of this study is to develop a three-dimensional model of a vibrating subsoiler using discrete element method, simulation frequency and oscillation angle on the performance of vibration subsoiler and determining different parameters affecting the simulation results. The information from model simulation will be useful for the design and optimization of vibrating subsoiler. For modeling soil mass as a granular material, the computer program PFC3D. Blade was moved with angular and transition speed in the positive x-axis direction. For non-vibrating blade only included transition speed and for vibration blade in addition to transition speed, angular velocity was also defined. Working depth was 38 cm and blade speed of 0. 89 meters per second was defined. To evaluate the effect of vibration angle on vibrating subsoiler different vibration of 27, 16, 8, zero,-14. 5,-22. 5 degrees in frequency of 4. 9 Hz and amplitude of ± 69 amplitude was tested by simulation. In all vibration tests in comparison with non-vibrating, with Increasing vibration angle (positive and negative), the amount of vertical displacement of blade increased which caused more soil rupture. Simulation results showed that the rate of boundary work, kinetic energy and friction work at positive angles were more than negative vibration angles. With increasing negative angle boundary work and friction work significantly decreased. Changing the angle from-22. 5 to 27 degrees decreased average bond energy of particles.

Grading based on product ripeness is important for marketing fruits and vegetables. Various methods have been used to determine fruit ripeness some of which are destructive and some nondestructive. In this study for determining the fruit ripeness of apple during storage an apparatus was designed and fabricated to measure the electrical capacitance of the fruit samples as an indication of fruit ripeness. In the next stage a model was proposed to establish a relationship between the capacitance and ripeness (maturity rate) of the apple fruits. The capacitance unit was used to measure the dielectric constant of two apple varieties; Red delicious and Golden Delicious. For each variety three fruit samples of 45 mature apples were harvested on one day. Each sample was divided into three groups of small, medium and large apples. Preliminary tests indicated that the capacitance unit can establish a good relationship between dielectric constant and fruit ripeness at a frequency of 100 kHz. Remaining tests were conducted to measure dielectric constants of all samples under controlled conditions of temperature and humidity at this frequency. Analyses of the results indicated that dielectric constant decreases as the fruit ripens. This frequency level was also used to conduct other tests for measuring the fruit hardness and total soluble solids (TSS) during ripening stage. Results indicated that fruit hardness decreases and TSS increases during ripening.

In order to study the effects of tillage, crop residue, and super absorbent on canola seedling emergence and yield, an experiment was conducted in Izeh region, east of Khuzestan in 2014. A strip spilt plot design was applied in form of randomized complete block using 3 replications. . The main treatments consisted of three tillage methods: conventional tillage (moldboard plow and disk) reduced tillage (combination tillage and disk) and no tillage(direct seeding). Secondary treatments were different amounts of super absorbent (0, 30, 60, and 90 kg/ha), and the third treatment was 2 levels of wheat residue (60% and 0%). Reduced tillage method with 66. 25% showed the maximum seedling emergence compared to no-till treatment (7. 59%). The maximum seedling emergence (68. 94%) was achieved from 90 kg/ha super absorbent. Reduce tillage method with 1674 kg/ha and no-tillage with 1134 kg/ha showed the maximum and the minimum yield respectively. Finaly, the results were shown that superabsorbent and crop residues were affected in increased soil moisture content and grain yield.

Each year, plant diseases cause considerable damages to the agricultural sector which their effect on the economy and food security is very important. Early detection of plant diseases is a useful strategy to reduce these losses. In recent years, researchers have used a variety of techniques such as machine vision for the diagnosis of plant diseases. In this study, a new system, consisting of digital image processing technique and also combination model of artificial neural network to distinguish three apple tree leaf diseases (namely Alternaria, apple black spot, and apple leaf miner pest) were used. In short, the process of digital image processing technique involves preparation, processing, and extraction of features of each of the sample images and the hybrid artificial neural network model was used to classify diseases. In this model, particle swarm optimization algorithm for network training (PSO) and Levenberg-Marquardt (LM) were used. After that, the operation of the proposed system for diagnosis of diseases of apple trees was evaluated. It is concluded that the system has a good performance for diagnosis accuracy was 99% and R2=0. 985, RMSE=0. 099. Finally, in comparison with other methods mentioned by other researchers for diagnosis of apple tree leaves diseases, the proposed system has higher ability.

Regarding the importance of quality of meat and other daily consuming food stuffs in the growth and health of human society, development of quality diagnosing and monitoring systems for food materials are being paid increasing attention by investigators. In this study, 40 beef samples were subjected to macroscopic imaging and dielectric power spectroscopy at 20 frequencies in the range of 5-100 MHz during five days of storage at 5 ° C. It was hypothesized that combination of the two sensing methods would result in more information on physicochemical changes of meat during ageing. For any beef sample, 42 attributes (i. e. 20 dielectric variables including dielectric power at different frequencies and 22 texture and color features of the image) were extracted. Classification analyses for the day of storage were performed with five algorithms of neural networks including multi-layer perceptron (MLP), multinomial logistic regression (MRL), functional trees (FT), logistic model trees (LMT) and Bagging aggregation. The results showed that the dielectric power at different frequencies decreased with the storage day from e. g. 250 µ W at 5 MHz on the first day to 100 µ W at the same frequency on the fifth day. The results showed that image parameters of beef were more effective in classification than dielectric variables but combining the information of the both sensory techniques, after reduction using PCA, resulted in classification accuracies of %78 for functional tree (FT) algorithm and %77 for Bagging classification with MLP as the base classifier.

Iran is the world's largest pistachio producer and exporter. Hence, the sustainability of the production of this strategic product is of particular importance. The high cost of pistachio harvesting has reduced the income of pistachio growers and created a serious challenge to the motivation of producing the pistachios. So, in this research, the contributing factors of mechanical harvesting of pistachio nuts in Kerman Province as the pole of pistachio production in Iran were studied. For this purpose, the Delphi method was used in three stages. Accordingly, 25 experts of pistachio cultivation experts and big growers of Rafsanjan and Kerman cities were considered as the research panel of the study. The final results of the research showed that the factors "Improving water use efficiency by supporting the implementation of new methods for irrigation of pistachio trees" and "allocating suitable credits for the pistachio nuts harvesting" with 96. 00% and 95. 00% agreements of the research panel’ s members were the first and second stimulants for the development of pistachio harvesting in Kerman Province. Also, the factors of "implementation of pattern projects for mechanized pistachio harvesting", and "Providing incentive policies for the development of mechanical harvesting among the pistachio growers" with 91. 00% of the agreement, jointly ranked as the second priorities. Investigating the barriers to the mechanical harvesting of pistachio also showed that the factors of the "smallness of most pistachio gardens" and "not being single-base or single-nesting of pistachio trees in the region" with the 97. 00% and 94. 00% agreements got the first and second ranks, respectively. Therefore, special financial supports for implementation of efficient irrigation systems, modification and renovation of old gardens, and the establishments of pattern projects for mechanized pistachio harvesting are inevitable. Also, consolidation of small pistachio gardens in the form of agricultural cooperatives in order to increase the group's financial strength as a backbone for the modifying the old gardens and the provision of pistachio harvesting equipments are indispensable.

In this study, energy consumption and environmental emissions of cookie production in Guilan Province of Iran was investigated. The required information was collected using questionnaires and interviews from 30 factories of cookie production. Equivalent energies of inputs and outputs were calculated based on the standardized energy coefficients. The results of this study showed that 30. 50 MJ of energy was consumed for production of one kilogram of cookie in which the highest share of energy consumption was allocated to natural gas with 17. 09 MJ kg-1. Based on life cycle assessment (LCA) results, global warming (GW) index was calculated as 3. 73 kg CO2 eq. per kilogram of produced cookie which about 51 percent of that was related to combustion of natural gas consumed in cooking process. Finally, the modeling of amount of yield and environmental impacts was conducted based on two models of artificial neural network (ANN) and adaptive neuro-fuzzy inference system (ANFIS). The results showed that ANFIS was capable of predicting yield with more accuracy and less error.

In this study, removal of the brown skin (seed coat) on the hazelnut kernel was investigated using infrared radiation. Evaluation of the infrared radiation method to achieve the highest percentage of seed coat loosening on the kernel. The effects of infrared emitter power at three levels of 800, 1200 and 1600 W, radiation duration at three levels of 2, 3 and 4 minutes, and the initial moisture content of hazelnuts at four levels of 4, 6, 8, and 10% wet basis (w. b. ) were investigated. Experiments were conducted at factorial in a completely randomized design with three replications. The peel loosening percentage was determined with using image processing method The results showed that by increasing in the IR radiation power and radiation time increased the percentage skin loosening significantly (p < 0. 05), while the increase of moisture content hazelnuts was caused reduced the percentage skin loosening (p < 0. 05). The most appropriate parameters the IR radiation unit were determined to be radiation power at 1600 W, the radiation time 3 min, and the moisture content of hazelnut 4% (w. b. ).

The manure management cycle from collection to application in dairy farming was evaluated from environmental and economic aspects for different scenarios including biogas production. For this purpose, manure characteristic is determined regarding the real feed ration composition. Environmental impacts and economic profitability of each scenario was calculated using standards and COMFAR program, respectively. The results showed although biogas production is costly but it is profitable with initial investment of 125 billion Rials (2, 777, 778 € ) and a payback period of about 3 to 4 years. The internal rate of return was calculated as 24% considering a discount rate of 20%. The internal rate of return shows that although this investment is risky, the amount of income is acceptable. Scenario 4 including digestate processing using a mechanical separator followed by composting has the maximum avoided methane emission (-261 kg CO2eq m-3). Emissions mitigation was calculated to be 36% and 17% in scenario 2 and 4, respectively. Solid/liquid separation and sand separation have less impact on emission reduction withy different economic advantages. Regarding the results of this study, a large amount of greenhouse gases and emissions to water and soil has mitigated thank to biogas production.

One of the ways to use solar energy is to use a solar dryer. But these kind of dryers have low efficiency that optimizes their absorbent plate to increase efficiency and save energy. For this purpose, the air flow inside the compartment of the adsorbent plate of the solar dryer was simulated using the computational fluid dynamics modeling and the heat transfer process, flow distribution and air velocity inside the compartment were analyzed and finally, the plates were compared in vitro. In this research, three different modes of the page with the same input and three different output modes (circular, conventional and perforated) were investigated. In a porous sheet with porosity, the plate was used with a coefficient of 0. 0314. The results showed that between analytical and empirical data, the explanatory factor (R2) was above 97%. There are circular and conventional heat accumulation in the corners, which, by changing the type of output and converting it to the perforated output state, Heat and heat accumulation are prevented.

In this study, a novel solar water desalination system was proposed. The designed system worked based on the humidification – dehumidification (HD) method. It was comprised of a photovoltaic-thermal (PVT) evaporator, a condenser, fresh and saline water tanks, an air blower, and a water pump. The performance evaluation tests were conducted at three velocities of air leaving the exhaust pipe (1, 1. 5 and 2m/s) and three levels of saline water passing over the photovoltaic module (94, 189 and 283kg. h-1 per m2 collector surface). The results showed that the highest evaporator efficiency was about 80% and the maximum daily evaporated water was about 7. 4kg, which were observed at the water flow rate of 189kg. h-1m-2 and the air velocity of 2m/s. Whereas, a maximum condenser effectiveness of 61% and fresh water production of about 4. 8kg per day were found at the water flow rate of 189kg. h-1m-2 and the air velocity of 1m/s. Although operating temperature of the conventional photovoltaic module was considerably higher than the PVT collector at the different working conditions, its electrical efficiency was also higher due to the more absorption of solar energy.

The first step in chicken breeding is the production of chicks, which requires a high-performance incubator. In this research, the performance of two incubators was compared. One of them was instrumented with a hybrid system based on fuzzy controller (HIFC), another one was the commercial incubator (ON/OFF). By comparing the important parameters to make suitable conditions for eggs hatchery, the percentage of eggs hatching, egg weight changes, chick’ s hatch time and energy consumption were compared and evaluated. The result showed that the eggs hatching ratio was 92. 13% for HIFC and 78. 16% for ON/OFF systems. The HIFC system showed a better result in controlling egg environmental conditions than the ON/OFF system, based on eggs weight changes and chick’ s hatch time. The energy consumption of the fuzzy controller was 31. 25% less than the ON/OFF controller. The amount of energy received by the solar hybrid system over a 21 day periods was 27. 20 kWh. For the HIFC system, the amount of energy needed for a hatching period was 24. 24 kWh which shows an excess energy of 12. 21%. For the ON/OFF system, contribution of solar hybrid system for power requirement was 77%.

The extracts of Mentha aquatique by ultrasound assisted and maceration (ethanol: water (80: 20)) extraction method were compared. The total phenolic content of extracts were obtained 45. 16 mg GA/g and 51. 92 mg GA/g Extract in maceration and ultrasound-assisted method respectively. The antioxidant activity of different concentration of extracts (50, 100, 250, 500, 1000 and 1500 ppm) were measured by DPPH radical scavenging method. The results shows that in both extracts by increasing in concentration of extract antioxidant activity were increased. Both extract at 1000 ppm of concentration have no significant statistical difference by TBHQ and they selected to add in sunflower oil. The thermal stability of samples containing separated and mixture extracts (1000 ppm) evaluated at 180 ° C. TBHQ at 100 ppm served as standard besides the control. The results showed that during frying process oil oxidation were increased. Control sample had the least oxidative stability and sample containing mix extract showed the highest oxidative stability. Finally 1000 ppm of the mix extract could act better than 100 ppm TBHQ in inhibition of lipid oxidation in sunflower oil during frying process and it suggest as a natural antioxidant to use in edible oils.