Journal Of Industrial Engineering International
Volume:6 Issue: 1, Jan 2010

This paper presents a mathematical model that could assist in measuring, monitoring and controlling tem-perature variation in cold and ‘red-hot’ metal working conditions of machining. A numerical analysis tech-nique of the temperature distribution, based on the theory of complex applied potential, was carried out using the principles of relationship analysis between the paths of heat supply in Cartesian plane when the heat path supplied to the material is orthogonal. The high level of temperature involved may effectively be predicted if a mathematical relationship that predicts the pattern of temperature distribution in a material is available. A case study example in a machining workshop is given. Simulation experiments are then carried out using Monte Carlo to increase the confidence in decision-making and provide data for significance testing. This was used as an input for testing for significance. Sensitivity analyses were also carried out in order to observe the degree of responsiveness of model parameters to changes in value. In all, five pairs of comparison were carried out among different workpiece materials. There are significant differences between workpiece materials made of steel and copper, copper and zinc, copper and aluminum. However, no significant differences exist in the model behavior of steel and aluminum, steel and zinc. It was observed that parameters are highly sensitive to changes in value. The framework could possibly be applied to milling and surfacing activities in the engineering workshop. This contribution may be helpful to small-scale enterprises that could not afford sophisticated and very expensive facilities.

In this paper, by introducing two virtual decision-making units (DMUs) called ideal DMU (IDMU) and anti-ideal DMU (ADMU) with fuzzy inputs-outputs, the efficiency evaluation of DMUs are done by fuzzy data envelopment analysis (FDEA). Therefore, we evaluate DMUs from the perspective of the best and worst possible relative efficiency. For each DMU two efficiencies are calculated while inputs and outputs are fuzzy. These two distinctive efficiencies are combined with the closeness coefficient (CC) index. The CC index is then used for an overall ranking of all DMUs. Finally, we compare the result of proposed fuzzy DEA model with León et al.’s (2003) results by representing a numerical example.

Determination of shipment quantity and distribution problem is an important subject in today’s business. This paper describes the inventory/distribution network design. The system addresses a class of distribution network design problem, which is characterized by multiple products family, multiple warehouses and retail-ers. The maximum capacity of vehicles and warehouses are also known. The resulting system focuses on two key goals: minimizing the lost sales cost as a costumer’s satisfaction factor and balancing sum of service dis-tances for different warehouses. In this paper we consider the distribution network problem formulated by 0-1 mixed integer linear programming model. Due to difficulty of obtaining the optimum solution in medium and large scale problems, a simulated annealing algorithm (SA) is also applied. The efficiency of this algorithm is demonstrated by comparing its numerical experiment results with those of SA algorithm and LINGO 6. package.

In the field of management, the delay within projects is a prominent and contentious issue. Due to the fact that delay leads to cost and time over-runs, it is often the subject of litigation claims and creation of managerial tensions. In a bid to bring such delays under control and also to diminish managerial tensions, it is necessary to recognize and understand the following four concepts:"types of delay", "extent of delay", its "causality" and "responsibility". Existing methods would just compare actual and target progresses with each other for project and its activities aimed at providing the extent of individual activity delay based on planned time schedule. This paper represents a forward chain approach to calculate self-delay while distinguishing the activities affecting project delay. Self-delay specifically deals with the activity itself and is irrelevant to the other activities. It consists of Stand By delay and progressive delay. Indeed, in the developed approach, quota of each activity in project delay is calculated. When analyzing a project status, a manager must calculate and analyze not only the delay in the entire project but also the delay in each activity and self-delay.

Funding decision is one of the financial strategic decisions of a corporation. There are also two other finan-cial strategic decisions that a corporation faces, the investment and the dividend decision. This paper de-scribes briefly the investment and the dividend decision, although its main focus is on funding decision. In de-scribing the funding decision the researchers will first explain the sources of funding in a corporation. Then, as funding decision is involved with determining the appropriate combination of the funding sources (debt, preferred stock, common stock, retained earnings), they will discuss about the debt equity ratio in different industries. After that they will describe the size and timing of corporate bond flotation and then they will present one model for corporate funding decision. Finally concentrating on the external sources of funding, they will discuss the funding decision in the perspective of determining optimal capital structure and will explain a mathematical programming model which can be used for determining the optimal capital structure.

Occurrence of chaotic behaviors because of fluctuations creation and their intensified transfer along the chain is one of the main causes of inefficiency of Material Requirements Planning (MRP) based supply chains. One of the reasons of the inefficiency is the lumpiness phenomenon. Through this phenomenon, some parts have an irregular production schedule, with nothing produced in some periods and large batches released in other periods. In this paper it is tried via the mathematical models to analyze this phenomenon. Using the mathematical deduction it is shown that the inventory fluctuations in upper levels of Bill of Material (BOM) in creation of lumpiness phenomenon are more effective than the inferior levels.

In an arid country like Kuwait with harsh and hot climate conditions, the scarcity of fresh water supplies presents a serious threat to sustainable socio-economic development and growth. Kuwait is an oil rich country with capital abundance and coastal locations enabled it to build desalination plants for fresh water production that is sold to the customers at highly subsidized prices. However, due to the sharp increase in population, and misuse of fresh water, there are shortages in water supply. Therefore, Kuwait should take appropriate measures to tackle this problem. This study examines the different course of actions required for water conservations by soliciting water experts` opinion. The problem is complex in nature, it constitutes a multi-criteria decision making problem since it comprises several criteria. The Fuzzy Analytical Hierarchy Process (FAHP) is utilized as a decision tool for finding the best course of actions to bring about water conservation. In this work, three factors are considered along with six water conservation policies.