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1951.

Free vibration of simply supported rectangular plates on Pasternak foundation: An exact and three-dimensional solution Pages 29-42 Download PDF

Keywords: Eigen-frequency, Elastic foundation, Free vibration, Pasternak model, Simply supported rectangular plates, Three-dimensional elasticity theory

Abstract:

This paper deals with exact solution for free vibration analysis of simply supported rectangular plates on elastic foundation. The solution is on the basis of three dimensional elasticity theory. The foundation is described by the Pasternak (two-parameter) model. First, the Navier equations of motion are replaced by three decoupled equations in terms of displacement components. Then, these equations are solved in a semi-inverse method. The obtained displacement field satisfies all the boundary conditions of the problem in a point wise manner. The solution is in the form of a double Fourier sine series. Then free-vibration characteristics of rectangular plates resting on elastic foundations for different thickness/span ratios and foundation parameters are studied. The numerical results are compared with the available results in the literature. Important parameters on the accuracy of plate theories and free-vibration characteristics of rectangular plates resting on elastic foundations are discussed.

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1952.

A goal programming method for deriving fuzzy priorities of criteria from inconsistent fuzzy comparison matrices Pages 29-42 Download PDF

Authors: Mohammad Izadikhah

DOI: 10.5267/j.msl.2011.10.005

Keywords: Fuzzy pair-wise comparison matrix, Goal programming, Ranking function, Triangular fuzzy number

Abstract:

Decision making problem is the process of finding the best option from all of the feasible alternatives. One of the most important concepts in decision making process is to identify the weights of criteria. In real-world situation, because of incomplete or non-obtainable information, the data (attributes) are often not deterministic and can be treated in forms of fuzzy numbers. This paper investigates a method for deriving the weights of criteria from the pair-wise comparison matrix with fuzzy elements. Finding the weights of criteria has been one of the most important issues in the field of decision-making and the present method uses goal programming to solve the resulted model. In addition, using a ranking function we convert each obtained fuzzy weight to a crisp one, which makes it possible to compare the criteria. The proposed model of this paper is supported by several examples and a case study.

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1953.

The effect of government spending on macroeconomic stability Pages 31-36 Download PDF

Authors: Keyvan Karimi, Rahebe Ghasemzade, Payam Khodaei, Payam Abdi

DOI: 10.5267/j.ac.2015.12.006

Keywords: Macro-economy stability, The Johansen-Juselius method, Government spending

Abstract:

Macroeconomic stability plays essential role on the performance of governments and attaining economic development. Therefore, governments can displace the demand curve and achieve different goals such as economic development and growth by considering financial instruments, which are available for them. Thus, the present study aims at investigating the effect of government spending on the stability of macro-economy for the time interval 1979-2011 using the Johansen-Juselius method. The results indicate that the variables of goods price index and services as well as government investment spending had positive effects and variables of exchange free rate, government consumption spending, and government tax revenues had negative effects on economic development.

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1954.

An exploration investigation on measuring the impact of information technology on bullwhip effect on supply chain management Pages 33-42 Download PDF

Authors: Vahid Shahabi, Mohammad Emami, Maliheh Sadat Monnavari, Fatemeh Ghods

Keywords: Fuzzy DEMATEL, Bullwhip effect, Supply chain management

Abstract:

Information technology plays an important role on the success of different organizations. In today’s competitive environment, there is a need to reduce the cost of products by increasing productivity and quality of products and services. Bullwhip effect is one of the most important issues influencing production planning reducing the efficiency of production planning by increasing unwanted materials, etc. Bullwhip effect occurs for many reasons such as lack of good demand estimation, poor communication between vendors and suppliers, etc. In this paper, we present an empirical investigation based on DEMATEL technique to find the effect of information technology on reducing the bad consequences of bullwhip effect. The study first uses systems dynamic to build a cause-and- effect relationship between different factors influencing bullwhip effect and then using fuzzy DEMATEL, the effect of information technology on bullwhip effect has been confirmed.

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1955.

One-pot synthesis of 2,4,5-tri-substituted-1H-imidazoles promoted by trichloromelamine Pages 35-42 Download PDF

Authors: BiBi Fatemeh Mirjalili, Abdolhamid Bamoniri, Najmeh Mohaghegh

DOI: 10.5267/j.ccl.2012.12.001

Keywords: Aldehydes, 1-2-Diketones, 2-4-5-Trisubstituted Imidazoles, Positive chlorine, Trichloromelamine

Abstract:

2,4,5-Trisubstituted imidazoles have many pharmaceutical properties and can be prepared via reaction of 1, 2-diketones with aldehydes in the presence of an acidic catalyst. In this work, we have prepared 2,4,5-trisubstituted imidazoles in the presence of trichloromelamine as a source of positive chlorine. Short reaction times, high yield, simplicity of operation and easy work-up are some advantages of this method.

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1956.

Developing a multi stage mathematical production management model for auto industry Pages 35-44 Download PDF

Authors: M. Ghorbani Salanghooch, A. Norang, M. Moameni

DOI: 10.5267/j.dsl.2012.10.003

Keywords: Khorasan razavi, Production management, Inventory management, Iran Khodro Iranian Company

Abstract:

In this paper, we establish an integrated mathematical production management model based on five parts insisted of finished goods production in production sites, inventory control of finished goods in production and distribution facilities, semi-finished goods production in producer’s facilities, inventory control of raw materials in production sites and Inventory control of semi-finished products. The main goal of developed model is to minimize total cost of company in the mentioned parts. Finally, the model is validated with 7 real-world case studies from auto-industry in one of the largest Iranian car producer company, Iran Khodro co and the empirical results are illustrated at the end of the paper.

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1957.

Fatigue life prediction in the damaged and un-damaged compressor blades Pages 43-50 Download PDF

Authors: S. Nakhodchi, E. Salimpour Maman

Keywords: Compressor blade, Fatigue life, Notch, Numerical analysis

Abstract:

A land-based gas turbine may operate at the different environment including corrosive and dusty environments. These conditions can cause early damages in the “cold” parts as well as in the “hot” parts of the gas turbine. In this research, fatigue life of a compressor blade is predicted with and without damages. Damage is considered as a notch at the blade and is classified as three types of short, medium and long notches. These are numerically simulated in the compressor blade and fatigue crack initiation life is calculated. Stress analysis is carried out using finite element analysis followed by fatigue life calculations. Furthermore, the influence of blade tip displacement on life of the undamaged and damaged blade is investigated. Moreover, the effect of damage & apos; s size and location on blade’s life is reported. This procedure can be tuned with corrosion damages observed during the minor inspection where the gas turbines are operating in the unusual environments.

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1958.

An exploration investigation on the role of industrial market information on the success of negotiations Pages 43-48 Download PDF

Authors: Homeyra Zare, Somayeh Hozouri

Keywords: Information technology, Factor analysis, Negotiation

Abstract:

Information plays an important role on having crystal clear image about market. A good awareness about products, vendors, new rivals, etc. always helps us offer better prices and reach better agreements. This paper presents an investigation on the role of industrial market information on the success of negotiations. The proposed study designs a questionnaire in Likert scale consists of 22 questions, distributes it among 228 Iranian experts and analyzes it based on principal component analysis. During the survey, the numbers of questions are reduced to 17. Cronbach alpha is calculated as 0.86 and Kaiser-Meyer-Olkin Measure of Sampling Adequacy and Approx. Chi-Square are 0.773 and 745.8, respectively. Based on the results of our survey, we have derived six factors including human resource management, integrated strategy, organizational software packages, communication factors, penetration factors, past perception and assessment process.

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1959.

Crystal structure of 3-(4-hydroxy-3-methoxyphenyl)-7,7-dimethyl-7,8-dihydrocinnolin-5(6H)-one Pages 43-48 Download PDF

Authors: Jabbar Khalafy, Mehdi Rimaz, Mahnaz Ezzati, Ahmad Poursattar Marjani

DOI: 10.5267/j.ccl.2012.11.002

Keywords: Arylglyoxal, Cinnoline, Crystal Structure, Dimedone, Hydrogen bond

Abstract:

The title compound 3-(4-hydroxy-3-methoxyphenyl)-7,7-dimethyl-7,8-dihydrocinnolin-5(6H)-one (3) was prepared via one-pot three component reaction of 2-(4-hydroxy-3-methoxyphenyl)-2-oxoacetaldehyde with dimedone in the presence of hydrazine hydrate and studied by the single crystal X-ray diffraction method. Its structure was also con?rmed by IR, 1H and 13C NMR spectroscopy. Compound 3 was crystallized in the monoclinic system, space group P21/c, a = 7.921(2) ?, b = 11.566(4) ?, c = 16.986(6) ?, B = 107.338(5)°, V = 1485.5(8) ?3, Z = 4, R1 = 0.0559 and wR2 = 0.1253. The crystal structure of 3 also shows a weak interaction between O3 and N2 atoms.

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1960.

Sourcing and pricing strategies for two retailers in a decentralized supply chain system under supply disruption Pages 43-54 Download PDF

Authors: M.A. Azarmehr, S Rezapour, R Tavakkoli-Moghaddam

DOI: 10.5267/j.msl.2011.10.004

Keywords: Competition Sourcing and pricing strategies, Decentralized supply chain, Supply disruption

Abstract:

This paper presents the decentralized supply chain with two suppliers and two competing retailers. It also investigates the sourcing and pricing strategies of two retailers in a decentralized supply chain system under a supply disruption environment. These retailers face their individual stochastic demand markets; however, they compete with each other through a two-stage price and service operation. The interactive dynamics among retailers is characterized, including the existence and uniqueness of the Nash Equilibrium in service and price games demonstrated.

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