Sharif Digital Repository

Traditionally, supplier selection should simultaneously take into account numerous heterogeneous criteria and then is a tedious task for the purchasing decision makers. The global supplier selection problem is more complex than domestic one and it needs more critical analysis. It becomes especially complicated when quantity discounts are considered at the same time. Under such manner, most studies often formulate such a problem as a Multi-Objective Linear Programming (MOLP) problem, and then scale it down to a Mixed Integer Programming (MIP) problem to handle the inherited multi-objectives simultaneously. However, this approach often neglects to consider scaling and subjective weighting... 

In this era, competition in economic fields is undeniable. According to huge amount of foreign trades between countries, economic prosperity of each country causes persuasion of foreign investors to come into that country for investment. Stock Exchanges is one sign of economic prosperity in each country, So prediction of the stock exchanges situation is very important. It is noteworthy that according to the importance of prediction in partial level, the necessity of predicting companies stock price is realized. According to the complicated term in this field, linear methods do not have appropriate efficiency for predicting, so nonlinear methods and especially Artificial Neural Networks are... 

Selection of appropriate acquisition mode for a required technology is one of the critical strategic decisions in formulating a technology strategy. Although a number of factors were found to be influential in the choice of technology acquisition mode, it still remains a void in the literature how to make a strategic decision, based on a huge set of those factors with the help of a systematic approach. This study deals with the selection of technology acquisition mode & method as a multiple criteria decision making (MCDM) problem. It tries to provide more appropriate solution for prioritizing technology acquisition modes through analytic network process (ANP), along with considering internal... 

We probably can say all people that are familiar with industrial engineering, have some information about supply chain management. Of course some people have more information about it and some have less. However, it is expected that they have some information about logistics because logistics is one of the most important elements in supply chain management. But it is sure that they have no information or less information about reverse logistics. That is why I have chosen this subject as my thesis. I have presented an optimization model with a numerical example  

In general, reliability is the ability of a system to perform and maintain its functions in routine circumstances, as well as hostile or unexpected circumstances. Redundancy Allocation Problem (RAP) is a combinatorial problem where it is going to maximize system reliability by discrete selection from available components. The main purpose of this study is to prove the effectiveness of robust optimization to solve RAP. Generally, robust optimization is a field of optimization theory where robustness is sought against uncertainty and/or variability of parameters' values. In this study it is assumed to have Erlang distribution density for components' failures where to implement robust... 

Saffron has an important role in non-oil export in Iran. This product has different known and unknown attributes. In recent years Iran has spent great effort to declare this product to global markets. But, despite these efforts and while Iran is the greatest saffron producer in the world, the global markets is in authority of Spain and Iran has an unknown position in global markets. On the other hand lack of attention to systematic cultivation of Saffron leads to reduction quality levels, decreasing production rate and finally decreasing profitability in Iran. Also poor distribution and marketing and lack of full declaring Iranian saffron, internationally lose a large portion of global... 

In this study it is attempted to investigate the impact of macroeconomic variables on the determination stock price in Iran.In this study it is used quarterly time series data of stock price and also macroeconomic variables including Growth of Consumer Price Index(Inflation), Iran Crude Oil Price, Exchange Rate, Gold Price, Liquidity, Money Supply and Gross Domestic Product for a period of 10 years (1381:1-1390:4). Data is obtained from monthly and quarterly reports, available on the website of the Central Bank of Iran and Tehran Stock Exchange Organization. In the analysis of the collected data, It is applied unit root tests, test for co integration, and utilize a Vector Auto Regressive... 

Analyzing reliability of large cold-standby systems has been a complicated and time-consuming task, especially for systems with components having non-exponential time-to-failure distributions. In this research, an approximation model, which is based on the central limit theorem, is presented for the reliability analysis of binary cold-standby systems whit non-identical components. The proposed model can estimate the reliability of large cold-standby systems with binary-state components having arbitrary time-to-failure distributions in an efficient and easy way. The accuracy and efficiency of the proposed method are illustrated using several different types of distributions, such as... 

Healthcare industry, in terms of gross national product, is one of the largest and fastest growing sectors of almost all countries. It is not surprising that a large amount of research has been focused on advancing medical practices and improving management methods in healthcare systems. One of the most important areas for improvement is patient flow management. Patient flow indicates the capability of a health care system in providing fast, reliable, and efficient services. Although capacity of health care system has grown, patients still have been facing long delays before getting into the system due to ineffective management. Queuing models can offer appropriate methods for analyzing and... 

In current societies, reliability is an important and fundamental factor in designing and manufacturing products and it cannot be ignored anyway; because sometimes malfunction and failure in a system can cause severe financial losses and health issues. In the field of optimizing reliability by redundancy allocation, one of the structures that has drawn many researchers attention is series-parallel structure. In the models proposed for reliability optimization in series-parallel systems, there is a restricting assumption which all components of a sub-system have to be homogeneous. In this thesis, new models are presented which enable components of a sub-system be non-homogeneous. Modeling is... 

Tile and ceramic industries plays a vital role in Iran’s economic due to significant added value and to be indigenous concerns. Therefore, in recent years huge investments have been performed by non-governmental agencies in this industry. In spite of high value of investment in this industry, efficient and updated management requires to reach the maximum output of the industry’s potentials. However, in recent years, supply has been exceeded of the demand in national markets. Moreover, the existence of the well-known abroad brands in the international markets has leaded to sever competition’s environment of this industry. In this circumstances, tile and ceramic companies to take the... 

To coordinate between different echelons in supply chains, it is necessary to analyze the multi-echelon inventory systems. Access to advanced technologies in Information Technology make some changes in the inventory management in these systems. Theses technologies that were gradually got inexpensive are attractive for researchers of the multi-echelon inventory systems. Using theses technologies, the information that leads to costs reduction in a supply chain is accessible economically. In this thesis, first efficient solutions for Base Stock and Reorder point, Quantity of order policies will be derived. Then, a serial two-level supply chain comprised of one retailer and one supplier will be... 

Decreasing cost, enhancing quality, increasing the customer satisfaction and the productivity to gain farther market shares are among the reasons for urging the companies to outsource their needs. In this study the definition of outsourcing, its advantages and weaknesses and the risks associated with it are presented and then models for decision making on outsourcing and its implementation process are discussed. As a scope for this mention, then the evaluation of outsourcing procedures for the paint shops is selected and studied. A model for the case is also presented. The case study is undertaken in Iran Khodro's paint shop during the years: 1379 – 1384 as a practical case. We can summarize... 

For offshore oil production, oil facilities should be continuously provided. The focus of this research is on the problems associated with a fleet of vessels from central depot(s) that are periodically utilized to serve wells and wellhead platforms with different demands and time limits. Iranian Offshore Oil Company, the largest offshore oil producer in Iran, was selected as a case study in this thesis. The main objectives is twofold. The first objective in the current study is to plan periodic routing of mobile wellhead servants and supporter vessels, as providers of general and technical services for the equipment on wellhead platforms. In some periods, the mobile wellhead servants require... 

Undoubtedly, reducing the organization's costs in today's world economy situation is a requisite for the survival of the organization. In order to continue their economic life, organizations must make their movements more effective by reducing costs and increasing agility and productivity. Various methods have been proposed to reduce costs, but before any measurements, identification of the reducible factors is very necessary.
Improving processes in an organization is considered as one of the best ways to reduce costs and increase profitability. In this research, the goal is to provide a model for reducing costs using process attitude so that the associated costs of the organization can... 

In recent years, most of the research in the field of reliability has been carried out over finding optimal combinations of units and their structures, trying to maximize the reliability of the system with respect to its cost. Numerous methods have been introduced. But, in this research, we introduce a new approach based on game theory, considering the system’s reliability and its cost as two players of a game. These two players start bargaining in search for an equilibrium point which none of them can violate seeking a better outcome. Finally, we show the superiority of our method by solving a traditional problem and comparing our results with the results of other optimization methods  

The ever-growing prevalence of gas-fired power plants has paved the way for significant changes in the electrical energy network applications in recent years. As a result, the mutual dependency between natural gas distribution systems and electrical energy distribution systems has been intensified. Thus, the integrated gas and electrical distribution system is faced with notable threats from natural disasters that can lead to disruptions in meeting the critical demands of the consumers as well as high monetary costs. The occurrence of unpredicted natural disasters such as floods, earthquakes, and hurricanes affects the performance of energy infrastructures. Given the low possibility of these... 

Productivity is the effective usage of input or resources for production or output. Input (including Energy, raw materials, capital and work force), which is being used for output (including final products or services performed by an organization). Productivity, increases gross domestic product and competitiveness, and improves level of living. Firms and related management levels play the main role in improving productivity. Using productivity cycle management brings the productivity to improve as a permanent process, specifies the rout for productivity and prepares the ground. The most important step in productivity cycle (PDCA) is the measurement of productivity. In this research several... 

Modern engineered products from individual parts to large systems shall be designed and produced to meet the required reliability at the time of the mission. A well-known type of systems in reliability issues is called k-out-of-m system. There are two common ways to enhance the reliability of these systems. These are: (1) increasing component reliability through more stringent acceptance sampling, and (2) improving system reliability through increases in component redundancy. The objective of this study is to determine the optimal plan in k-out-of-m systems. In fact, we seek to find an optimal plan for a decision maker considering his or her limitations such as cost and reliability. An... 

In the complicated industrial world interactions between human and machine always result in the higher human risk. Moreover, human may act differently in same situations on the basis of iner conflict, complexity or diverse motivations. Therefore, investigating human reliability is really more complicated than reliability of some mechanic parts of the system.within this study, human reliability factors have been intensively explored and based on Mamdani Fuzzy Inference and PROMETHEE these factors ranked for numerical example. Using this method, one may benefit its dynamic adaptivity and also its ability to contain eperts knowlegde within the Fuzzy Role Base. Furhtermore, Validity of the...