Development of a suitable method for color sorting of agricultural products such as: tomato, apple and orange, based on surface reflection and image formation was the goal of this research. A suitable scheme of color differentiation using an optic head and electrical processing circuitry for separating ...
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Development of a suitable method for color sorting of agricultural products such as: tomato, apple and orange, based on surface reflection and image formation was the goal of this research. A suitable scheme of color differentiation using an optic head and electrical processing circuitry for separating red from green and other colors is presented. A photo-conductive transducer, electrical resistance of which varied with different colors, was selected as the sensor element of the optic head. Tests indicated that sensor resistance for blue and green was greater than that for yellow and red and furthermore, it increased with increasing distance of the object from the sensor. The system can easily be adjusted for other colors using potentiometer resistance change. Thus, the designed system can be used for separating red tomatoes from green ones, green oranges from orange ones, red apples from yellow and green ones, etc. Tests were conducted to check the system performance and to study the effect of some parameters such as type of fruit and ambient light intensity and so product shape and size on color detection accuracy of the system. Results indicated that main and interaction effects of these parameters on detection accuracy were not significant and the system is capable of color differentiation under varying working conditions.
Evaporation from the soil surface has an important role in the water balance model in nature, so that the major part of rain fall and irrigation water in arid and semi-arid regions is lost via evaporation from the soil surface. In such areas, there are some regions with high water table and because of ...
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Evaporation from the soil surface has an important role in the water balance model in nature, so that the major part of rain fall and irrigation water in arid and semi-arid regions is lost via evaporation from the soil surface. In such areas, there are some regions with high water table and because of evaporation from the soil surface, salts accumulation also occur in the soil surface. So evaporation from the soil surface not only losses water, but also it is responsible for soil salinization. The main difficulty in accurate estimation of nonsteady evaporation in field conditions is the lack of simple functions with minimum input data for calculating water losses in Water Balance model. The main goal of this study is to introduce a simple method for calculating evaporating from the surface of the bear soil in arid and semi-arid regions with a deep water table. Soil water characteristic curves, water content versus depth curve, nonsteady and one dimensional water movement were used in this method, and the rate of anticipation accuracy was determined by the real conditions of the region. Since it is difficult to make the lower boundary conditions similarity, Applying the physical model in regions with a deep water table is impossible. Applied parameters of this model were determined by using Water Balance model in different regions and with respect to the existing position and trend of changes. By using these parameters, the final amount of evaporations were calculated for Karaj, Torbat Heidarieh and Mashhad 174, 116, and 297 mm respectively during 20, 44, and 62 days periods in June 2003, August and September 2002, July and August 2002. In this study, Zero Flux Plane (ZFP) was applied with the initial and boundary conditions dominant in the evaporation process which unlimited depth forms its lower boundary conditions. Water content – depth curve was drawn by using the results obtained from field. The physical parameters were obtained from laboratory tests using undisturbed soil samples. First the water characteristic curve was drawn, Then the hydraulic potential-depth curve was obtained from those results. The depth of evaporation and final evaporation were obtained based on the above mentioned curves and ZFP. The amount of evaporation in above regions are 182, 117, and 297 mm respectively for the above mentioned periods. The differences between the results obtained from ZFP and Water Balance model were less than 5% which is not so important in field experiments, and there is a good crossespondance between them.
It is the aim of every master baker to produce a bread of high quality that is well aerated, tasty and has an appealing appearance. The decisive factors in the production of such a bread are flour quality dough mixing, dough temperature, fermentation, manipulation, molding proving and baking. In this ...
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It is the aim of every master baker to produce a bread of high quality that is well aerated, tasty and has an appealing appearance. The decisive factors in the production of such a bread are flour quality dough mixing, dough temperature, fermentation, manipulation, molding proving and baking. In this study the effect of three important factors: extraction rate of flour, method of mixing and additives were investigated. Sampels of wheat (M.V.17) was milled experimentally to produce flour extraction rates of 89, 86, 84, and 81%, and the effect of extraction rate with and without additives (glycerol mono stearate and sodium stearoyl -2- Lactylate) in rheological properties of flour were determined. Lower extraction rate made better characteristics and addition of above additives caused better farinography indexes. In second stage samples of flour and additives were mixed in spiral mixer with three methods, then dough samples prepared and finally bread samples baked. Results of panel test showed that increasing in extraction rate made darker color crust and crumb, and lower quality in bread. In the other hand mixing method involved low speed and high speed caused good development and quality in flour, dough and bread. Addition of glycerol mono stearate (0.5%) could delay staling in all samples.
Subsoil compaction, may occur naturally or a consequence of machinery traffic, causes reduction in crop yield. The aim of this work was to characterize the effects of subsoiling and irrigation on yield of corn. This study was conducted on the silty loam soils of Miyandoab agricultural research station ...
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Subsoil compaction, may occur naturally or a consequence of machinery traffic, causes reduction in crop yield. The aim of this work was to characterize the effects of subsoiling and irrigation on yield of corn. This study was conducted on the silty loam soils of Miyandoab agricultural research station on the base of split plots design with 12 treatments and 4 replicates during the 1999 and 2000 years. Irrigation treatments were applied in main plots and consisted of 11, 14, 17, and 21 days irrigation interval, and subsoiling treatments were applied in the sub plots and consisted of 45 and 55 cm depth subsoiling and no subsoiling. The corn yield in 11, 14, 17, and 21 days irrigation interval were 13, 12.09, 11 and 9.45 t/ha and subsoiling treatments and no-subsoiling were 11.4, 11.3 and 10.6 t/ha respectively. The irrigation and subsoiling had significant effect on corn yield. The highest yield (13 t/ha) among the irrigation treatment was 11-day irrigation interval, and in subsoiling treatments, yield of 11.3 and 11.4 t/ha was determined respectively.
Because of water shortage in arid and semi-arid regions, reuse of wastewater and treated effluents for agricultural irrigation has become an essential matter now. While these kinds of water contain a lot of nutrients such as nitrogen, by using them we could be able to increase the soil fertility and ...
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Because of water shortage in arid and semi-arid regions, reuse of wastewater and treated effluents for agricultural irrigation has become an essential matter now. While these kinds of water contain a lot of nutrients such as nitrogen, by using them we could be able to increase the soil fertility and decrease both the chemical nutrient consumption and the costs of agricultural production. However, due to high potential of pollutant and transferability of nitrate components (NO3) through soil, careless application could cause ground and surface water contamination. With this regard, in order to investigate the transformation of nitrogen below the root zone as a result of irrigation with wastewater, a series of lysimeter studies were carried out in Tehran area. A statistical “factorial experiments in the form of randomized complete design” (3x3x3) was used. Raw and treated domestic wastewater of Ekbatan housing complex and well water (control) have been applied for irrigation of raw edible vegetables such as parsley, carrot and tomato for two years. The results showed that nitrogen leaching through soil to drain depth, were between 12.93% to 33.75% of entranced amount for irrigation with raw wastewater and 23.30% to 38.17% for treated wastewater. Also, mass balance analyses indexed by nitrogen showed a mean efficient reduction of 96.6% to 98.9%. Maximum NO3 concentration during two years was about 12 mg/lit, which happened in drainage water of lysimeters that irrigated with raw wastewater. This amount of NO3 was very lower than the permissible NO3 amounting of Iranian standards(50 mg/lit) for discharge the effluents to surface water resources.
Nowadays, potato is one of the most important foods in the people¢s diet. Daily consumption of potato is increasing in Iran significantly; therefore the study and research on this product is essential. In order to the components of potato, three varieties of potato (Diamant, Aola and Draga) were ...
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Nowadays, potato is one of the most important foods in the people¢s diet. Daily consumption of potato is increasing in Iran significantly; therefore the study and research on this product is essential. In order to the components of potato, three varieties of potato (Diamant, Aola and Draga) were chosen from thirty six fields in north of Khorasan province. Each variety was harvested from 12 fields and transported to the laboratory in agricultural research center of Khorasan. Measurement of protein, dry matter, starch, reducing sugars and density were done after harvest and after 6 months storage. The results were analyzed by SPSS, V9 software. The results showed that Aola had the highest dry matter and starch so it is recommended for processing in industries. It can be used for producing chips, french fries and starch.
Pure rockfill dams have been found specific attention in watershed management and flood control, recently. In addition to hydraulic specific features, one of the important advantages of these structures is their consistency with nature and environment. Normally, floods are accompanied with high sediment ...
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Pure rockfill dams have been found specific attention in watershed management and flood control, recently. In addition to hydraulic specific features, one of the important advantages of these structures is their consistency with nature and environment. Normally, floods are accompanied with high sediment loads which may enter the body of dam. When flow through dam body governed by hydraulic gradient higher than the critical one, sediment will pass through and be transported downstream the dam. If sediment load transported through rockfill dam is more than sediment transport capacity of downstream channel, then erosion may occur downstream and if less, excess sediment load will be settled down. Therefore, it is important to determine sediment transport capacity of flow through rockfill dams before building them. For this purpose a 1-D model for flow through rockfill dam accompanied with sediment transport relationship in coarse porous media (rockfill) has been developed. The rockfill dam used in the experiments was consisted of a rectangular block of 600 mm long, 300 mm wide and 300 mm high. The experiments were conducted for two rockfill (14.5 and 21mm) three sediment sizes (0.256, 0.362 and 0.512 mm) , and five flow rates (5 to 13 l/sec). The refered relationship includes some coefficients related to the rockfill media and its flow turbulence which need to be identified. In this regard, experiments have been conducted. The results of the model compared to the observed experimental data have been shown to be reliable.
