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Showing 5 results for Dea

R. Taherkhani, M. Shivazad, M. Zaghari, A. Zare Shahne,
Volume 10, Issue 1 (4-2006)
Abstract

A chick bioassay with chemically defined amino acid (AA) diets was conducted to compare four different AA profiles: the NRC 1994, Feedstuff 2002, Rhone Poulenc Animal Nutrition 1993(RPAN) and Illinois Ideal Chick Protein (IICP) AA profiles. This battery study involved male and female chicks during 7 to 21 days of age. Indispensable AA were rationed to lysine according to requirement ratios presented in the four profiles. Digestible lysine set at 1.07 and 0.98 % of diet for male and female respectively. This experiment was carried out in a completely randomized block design using 2 5 factorial arrangement with for replicate per each diets were kept isonitrogenous (2.6 % N ) by varying levels of L-glutamic acid. All diets were checked to have at least 0.3 % proline and 0.6 % glycine. Diets for all profiles contained 3200 kcal ME/kg and a positive control diet were used according to NRC 1994 recommendations. Chicks fed a common corn-soybean meal diet for 160 h and were raised in the floor pen. Then chicks weighted individually and allocated to battery pens so that most uniformity between pens occurs. Four battery pens of five chicks were fed one of four different profiles or positive control diet in both male & female. Weight gain and feed efficiency measured for each pen at day 21. Results indicate an improved weight gain and feed efficiency in male rather than female (p<0.5). Chicks fed positive control diet weighted more (p<0.5). Between semi purified diets chicks fed diets formulated with NRC AA ideal ratios had significantly (P<0.5) better weight gain and gain: feed in both sexes relative to IICP and RPAN, but not to Feedstuff. RPAN had worst weight gain and feed: gain in females. Results of this experiment indicated that new ideal ratio of theronine (relative to lysine) in IICP for starter period may be under-estimated.
M. Zibaei, M. Jafari Sani,
Volume 12, Issue 43 (4-2008)
Abstract

While technical efficiencies of firms that are estimated with respect to a given frontier are comparable, this is not normally valid the case among firms that operate under different technologies. Such problem arises when comparisons of firms from different regions of country are involved. This study uses the concept of the metafrontier function to investigate regional differences in milk production technologies of Iran. Metafrontier function was estimated using non-parametric data envelopment analysis (DEA) and required data are collected from 726 questionnaires. Results of estimating regional frontier production function indicated that, gap between the best producer and other producers in Yazd is minimum and it is maximum in Esfahan. Also estimation of metafrontier production function and technical gap ratio showed that Tehran and Yazd have higher technical operation in comparison with other studied provinces.
J Torkamani, H Dehghanpor,
Volume 13, Issue 48 (7-2009)
Abstract

The objective of this study was to investigate the demand of food and nonfood commodities among urban and rural households. To this aim, an appropriate functional form and approximation index were established. Then, Deaton and Mulbaer Iterative (DMI) approach as a linear approximation of Almost Ideal Demand System was used. The study horizon was also 1362-1383(1983-2004). The findings revealed that for urban households housing, fuel, power and furniture, household operations and entertainment, education and food, beverages, tobacco are considered necessary. While clothing, footwear and medical care and transport, communication and other goods are consumed as superior commodities. For urban households, a weak complementary and substitution relation among selected commodities was recognized. In the case of rural households clothing, footwear and food, beverages, tobacco were revealed to be necessary, while housing, fuel, power and medical care and entertainment, education were found superior. For the rural households only furniture and house operation was found elastic. The compensated and uncompensated self price elasticizes were similar regarding the sign and magnitude coefficients for rural and urban households.
Mohseni Movahed S. A.,
Volume 20, Issue 76 (8-2016)
Abstract

In the ICSSDOM simulation-optimization model, simulated annealing algorithm is combined with a hydrodynamic simulation model named ICSS. In this model the ability of weighting of indicators is also considered. In this study, using this model the performance of the S-L-R5 canal in the DEZ irrigation network was evaluated in a period of 10 days. With presenting a proposed method for weighting the indicators and its various options, using parametric sensitivity analysis, optimal adjustment of intake and check structures was obtained. It was found if the coefficient of each index is selected as a direct ratio of the ideal improvement potential of the indicator, the percentage of the improvement is more than the other investigated options. In addition, due to the interaction of the indicators in the multi-objective functions, the consistency of the weighting method with the nature of the optimization problem in this study has been shown. Statistically, the adequacy of the 10-day period of study was confirmed. The model validation with mathematical asymptote method shows 6% error which indicates the model is valid. For example, on the first day, based on the option three (The optimal option), the optimal gate opening for 5 intakes and one check control was between 3.9 to 14.7 Cm. In this condition optimal delivery was between 46 to 178 liters per second.


F. Farsadnia, B. Ghahreman, R. Modarres, A. Moghaddam Nia,
Volume 22, Issue 3 (11-2018)
Abstract

In recent years, the joint distribution properties of drought including severity and duration have been widely evaluated using copula. Few studies, however, have worked on drought modeling based on stream flow, especially in semi-arid regions such as the southern regions of Iran. This study followed two purposes. The first purpose was to find the appropriate marginal distribution function for hydrologic drought duration and severity, and the other one was to find appropriate copulas. First, the severity and duration of hydrological droughts in the hydrometery stations in the Karkhe basin were extracted by the run’s theorem, and the absence of trends was tested using the modified Mann-Kendall trend test. Appropriate marginal distribution functions for duration and severity drought were derived by using the linear moment's method. In addition, copula’s parameters for Frank, Clyton and Gumbel families were calculated by both direct and indirect methods. The best copulas were selected by the goodness of fit tests. Finally, the joint and conditional return periods for duration and severity drought were derived for each station. The results showed that drought severity and duration for all hydrometery stations in Karkhe basin followed both the generalized extreme value marginal distribution function and Gumbel copulas family, which could be used for regional copulas modeling.


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