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Arayesh B.,Islamic Azad University at Ilam
American Journal of Agricultural and Biological Science | Year: 2011

Problem statement: 40-year history of agricultural production cooperatives in the country shows that this type of exploitation system has faced many ups and downs during this period. First, despite the help and support by the government, the cooperative sector has not been able to play a major role in the development of the country and its share has not exceeded 3% of development program. The main aim of this study is identifying the factors affecting the participation of Shirvan-Chardavol township’s agricultural cooperatives’ members.Approach: This casual comparative applied research which uses survey method for data accumulation, is of Quasi-experimental research type because of impossibility of controlling the research variables. A researcher-made questionnair was used as the main tool for gathering data. The face and content validity of the questionnaire were confirmed by a group of university professors and cooperative experts; also the reliability of the questionnaire was confirmed through calculating the Kronbach alfa coefficient (a = 0.80).Results: The statistical society of the research included 751 active members of Shirvan-Chardavol township’s agricultural cooperatives, among which 260 people were selected for the study using classified proportional random sampling method and with the aid of Morgan sample-volume table. Data processing was performed using SPSS estatistial software, as well as descriptive estatistics (central and inferential indexes) and analytical estatistics (correlation coefficients and stepwise multiple regression analysis).Conclusion: The correlation coefficient results show that there is significant relationship between the variables like age, background history of membership in cooperatives, the members’ agricultural land areas, annual income of the members, socio-cultural features, economical features, educational-extensional features, managerial factors, psychological features, political factors and communicational-informational factors from the one hand and the dependent variable of agricultural cooperatives’ members’ level of participation from the other. The multiple regression analysis results showed that variables like political, economic, managerial and social factors have positive effect on the dependent variable of agricultural cooperatives’ members’ participation, describing 65% of the changes of the mentioned dependent variable. © 2011 Science Publications. Source

Nosrati M.,Islamic Azad University at Ilam | Mirzaee M.,Islamic Azad University at Kermanshah
IEEE Microwave and Wireless Components Letters | Year: 2010

In this letter, a new model for further reducing the size and increasing the bandwidth (BW) of a class of bandpass filter (BPF) utilizing multi-mode resonator is presented. A new technique based on spiral transmission line loading to achieve higher BW and further size reduction is analyzed for this class of BPF. A compact ultra wideband microstrip BPF is proposed by using this technique. The capability of tuning the transmission zeroes in the proposed model is also studied. Estimates for the frequencies of these transmission zeroes are directly presented. The overall BW of the proposed BPF is shown to be increased more than 12.6% and its size to be reduced more than 70% compared with the conventional ones. The proposed BPF provides a relatively wide 3 dB fractional bandwidth of 72.6% frequency response with two transmission zeros at the lower and upper stop-bands to provide a very sharp cutoff and low passband insertion-loss and good return-loss characteristics. © 2010 IEEE. Source

Abbasi Z.,Islamic Azad University at Ilam
Journal of the Taiwan Institute of Chemical Engineers | Year: 2012

The aims of the study were to investigate the effect of polyvinyl alcohol (PVA) and nano-SiO 2 within the thermoplastic starch (TPS) blends on the rate and extent of starch enzymatic hydrolysis using enzymes α-amylase and amyloglucosidase. The results of this study have revealed that blends with a nano-SiO 2 content at 5wt.% exhibited a significantly reduced rate and extent of starch hydrolysis. The results suggest that this may have been attributed to interactions between starch and nano-SiO 2 that further prevented enzymatic attack on the remaining starch phases within the blend. The total solids that remained after 6000min were 54wt.% (TPS:PVA); 61wt.% (TPS:PVA:1% nano-SiO 2); 64wt.% (TPS:PVA:3% nano-SiO 2); 68wt.% (TPS:PVA:5% nano-SiO 2). The rate of glucose production from each nanocomposite substrates was most rapid for the substrate without nano-SiO 2 and decreased with the addition of nano-SiO 2, for TPS:PVA blend (226μg/mlh), 166μg/mlh (TPS:PVA:1% nano-SiO 2), 122μg/mlh (TPS:PVA:3% nano-SiO 2) and 94μg/mlh for (TPS:PVA:5% nano-SiO 2). Enzymatic degradation behaviour of TPS:PVA:nano-SiO 2 was based on the determinations of water resistance, weight loss and the reducing sugars. It has been established that the nanoparticles hinder degradation, while the susceptibility to enzymatic degradation varies in the order: TPS:PVA>TPS:PVA:nano-SiO 2. © 2011 Taiwan Institute of Chemical Engineers. Source

Bisadi H.,Iran University of Science and Technology | Tavakoli A.,Islamic Azad University at Tehran | Tour Sangsaraki M.,Iran University of Science and Technology | Tour Sangsaraki K.,Islamic Azad University at Ilam
Materials and Design | Year: 2013

In last years, friction stir welding (FSW) method has represented better microstructure and mechanical properties than conventional methods in welding aluminum alloys. Many studies have been performed on joining aluminum alloys in cases of similar and dissimilar FSW lap joints. In this study FSW was used to join sheets of AA5083 aluminum alloy and commercially pure copper and the effects of process parameters including rotational and welding speeds on the microstructures and mechanical properties of the joints were investigated and different joint defects were analyzed. The experiments were performed with rotational speeds of 600, 825, 1115 and 1550. rpm each of them with welding speeds of 15 and 32. mm/min. It was observed that very low or high welding temperatures lead to many joint defects. Also intermetallic compounds and their effects on the mechanical properties of the joints were investigated. The best joint tensile shear properties were achieved at the rotational speed of 825. rpm and welding speed of 32. mm/min. © 2012 Elsevier Ltd. Source

Aziz A.,Gonzaga University | Khani F.,Islamic Azad University at Ilam
Journal of the Franklin Institute | Year: 2011

The homotopy analysis method (HAM) is applied to generate an analytic solution for heat transfer in a moving fin of variable thermal conductivity which is losing heat by simultaneous convection and radiation to its surroundings. The accuracy of the analytic solution is validated by comparing it with the direct numerical solution of the problem. The analytic solution is found to be accurate to at least three places of decimal for a wide range of values of the parameters that are commonly encountered in thermal processing application. Graphs displaying the results are interpreted in physical terms. © 2011 The Franklin Institute © 2011 Published by Elsevier Ltd. on behalf of The Franklin Institute. Source

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