In this paper, a technique has been developed to determine the optimum mix of logistic service providers of a make-to-order (MTO) supply chain. A serial MTO supply chain with different stages/ processes has been considered. For each stage different logistic service providers with different mean processing lead times, but same lead time variances are available. A realistic assumption that for each stage, the logistic service provider who charges more for his service consumes less processing lead time and vice-versa has been made in our study. Thus for each stage, for each service provider, a combination of cost and mean processing lead time is available. Using these combinations, for each stage, a polynomial curve, expressing cost of that stage as a function of mean processing lead time is fit. Cumulating all such expressions of cost for the different stages along with incorporation of suitable constraints arising out of timely delivery, results in the formulation of a constrained nonlinear cost optimization problem. On solving the problem using mathematica, optimum processing lead time for each stage is obtained. Using these optimum processing lead times and by employing a simple technique the optimum logistic service provider mix of the supply chain along with the corresponding total cost of processing is determined. Finally to examine the effect of changes in different parameters on the optimum total processing cost of the supply chain, sensitivity analysis has been carried out graphically.

Kinetic studies were made of the reactions between triphenylphosphine 1 and dialkyl acetylenedicarboxylates 2, in the presence of NH-acids, such as benzotriazole, 5-methylbenzotriazole or 5-chlorobenzotriazole 3 (as a protic/nucleophilic reagent). To determine the kinetic parameters of the reactions, they were monitored by UV spectrophotometry. Useful information was obtained from studies of the effect of solvent, structure of reactants (dialkyl acetylenedicarboxylates and NH-acids) and also concentration of reactants on the reaction rates. First and third steps (k2, k3) of all reactions were recognized as a rate determining and fast steps, respectively. Proposed mechanism was confirmed on the basis of experimental data.

Radio-frequency identification (RFID) is the wireless non-contact implementation of radio-frequency electromagnetic fields to transfer necessary data to identify and to track tags attached to objects, automatically. RFID has been successfully used for supply chain management (SCM) problems in order to reduce errors associated with inventory. This paper uses RFID technique in five different scenarios of labeling, errors in stolen parts, waste, wrong replacement and delivery. The study uses simulation technique based on Enterprise Dynamics to analyze three parts in an auto industry. The study considers different criteria including inventory error estimation, profitability, profitability, customer satisfaction and SCM performance. The preliminary results indicate that the proposed method is capable of optimizing most objectives, significantly.

Composite materials due to high strength and stiffness to their weight ratio are widely used in different structures. Hence, it is necessary to predict their failure behavior under loading. The delamination due to interlaminar stresses at free edges is one of the most important damage modes in laminated composites. In this study, this mode in cross-ply and angle-ply laminates has been investigated using a cohesive zone model. The advantage of this method is the possibility of modeling the delamination initiation and propagation without requirement to the presence of initial crack and remeshing. Hence, at first an interface element based on bilinear cohesive law was implemented in Ansys. Next, laminated plates with different lay-ups under uniaxial tension loading were modeled. Also Hashin’s failure criteria were used to predict ply damage initiation. Numerical results show that in angle-ply laminates with small fiber angle orientation, delamination in the shear mode is the dominant mode in the loss of structural strength. The numerical and experimental results for global load-displacement response show a good agreement. Also numerical results show that in cross-ply laminates even under in-plane loading, the damage behavior extremely depends on the stacking sequence. Studies show that in cross-ply laminates under uniaxial tension, if 90o plies are inserted in top and bottom surface of the laminate, the mode I delamination and matrix cracking will start later.

This paper presents an investigation on the role of packaging design on persuading consumer to buy different products in city of Tehran, Iran. The proposed study designs a questionnaire in Likert scale consists of 26 questions, distributes it among some Iranian experts and analyzes it based on principal component analysis. During the survey, the number of questions is reduced from 26to 23. Cronbach alpha is calculated as 0.88 and Kaiser-Meyer-Olkin Measure of Sampling Adequacy and Approx. Chi-Square are 0.80 and 1880, respectively. Based on the results of our survey, we have derived five factors including requirement attributes, proportionality components, consumer choice, product appearance attractiveness and consumer characteristics.

Efficient synthesis of quinoxaline derivatives from the reaction of ?-diketones and o-phenylenediamines in the presence of Keggin-type heteropolyacids (HPA) such as H3PMo12O40, H4SiW12O40, K7PMo2W9O40, H3PW12O40.SiO2 and H3PW12O40 in high yields and short reaction times, and at room temperature is introduced.

Renewable energy technologies (RET) have faced a number of constraints that have affected their rate of adoption. This can be attributed to the presence of complex dynamic factors associated with the technology adoption process. This paper simulates the dynamic behaviour of the RET adoption process, from a systems dynamics point of view. Complex dynamic interactions between technology adopters, policy makers and policies are captured based on systems thinking concepts. Based on a set of input policy parameters and variables, the behaviour of RET adoption is investigated and analyzed. Sensitivity experiments and further “what-if” experiments are carried out to obtain in-depth understanding of RET adoption process. Useful managerial insights are drawn from the simulation results, relevant to decision makers concerned with renewable energy technology innovations and their adoption.

One of the methods to reach continuous improvement on economy is to boost export and target international market. However, there are some limits on available resources, which present most developing countries for improvement of export activities. One way to overcome such trouble is to use foreign direct investment but this may happen only when we could determine major barriers and overcome the challenges. The present study presents an empirical investigation to detect important barriers on foreign direct investment in Iranian industries. The proposed study uses structural equation modeling to detect major barriers for export development. The results of our survey indicate that there were four factors including economic factors, feasibility study, infrastructure for investment and investment resources influencing on foreign direct investment.

In this paper, harmonic forced vibration of circular functionally graded plate integrated with two uniformly distributed actuator faces made of piezoelectric material is studied. The material properties of the functionally graded substrate layers are assumed to be graded in the thickness direction according to the power-law distribution, also the distribution of electric potential field along the thickness direction of piezoelectric layers is modeled by a quadratic function. The governing equations are solved for simply supported boundary condition of the sandwich circular plate and the solutions are presented by elementary Bessel functions. The performance of the present model is compared with that of ?nite element analyses as well as other available literature by the presentation of comparative results obtained for several examples encompassing different power indexes and vibration modes. The results show that thickness of piezoelectric layer and changing the power index in FG material has a significant influence on the deflection and natural frequencies of system.

This study employs the generalized autoregressive conditionally heteroskedastic in the mean (GARCH-M) methodology to investigate the return generating process of Jordan, Kingdom of Saudi Arabia (KSA), Kuwait, and Morocco stock market indices. The tradeoff between returns and the conditional variance is found to be positive in all markets. In other words, the empirical findings show that investors are rewarded for their exposure to more risk in these financial markets. This result is consistent with both financial theory and empirical finance.