An improper machine setting in a hard disk drive assembly process could reduce the read/write area of hard disk drives. This paper presents the methodology to increase the read/write area of hard disk drives by finding an optimal machine setting that minimizes the track zero. The Six Sigma improvement approach was applied. The design of experiment technique helped indicate the optimal levels of significant factors, which were the number of screw turn, the rotating pin height, and the cylinder force, that yield the minimum track zero. The results showed that the mean of track zero was decreased from 16,185 to 15,120 tracks and the standard deviation was decreased from 1,116 to 633 tracks resulting in the increase of the process capability index (Ppk) of the track zero performance from 0.54 to 1.52.
11. 
Improvement of track zero to increase read/write area in hard disk drive assembly process Pages 165-176
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Authors: Prapod Ruthaiputpong, Napassavong Rojanarowan
Keywords:
Abstract:
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 3 | Views: 2039 | Reviews: 0
12.
The impact of cash management on the performance of manufacturing companies in Nigeria Pages 177-192
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Authors: Matthew Abioro
Keywords: Cash, Cash Management, Performance and Liquidity
Abstract:
This study examined empirically the impact of cash management on the performance of manufacturing companies in Nigeria-A study of Cadbury Nigeria Plc. The researcher used both secondary and primary data for data collection. For clear analysis, the study centres on two broad variables; the dependent variable which is performance and the independent variable which is Cash management. Two different hypotheses were formulated and tested using descriptive statistics and correlation coefficients techniques respectively in order to establish whether there is a significant relationship between cash management, performance and liquidity. The results of the study suggested that a significant relationship exists between cash management on performance of manufacturing companies in Nigeria. It was also discovered that mere availability of cash (liquidity) without proper management does not necessarily translate into favorable performance for manufacturing companies. Hence, need for effective cash management for better performance.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 3 | Views: 22740 | Reviews: 0
13.
Optimization in an instantaneous economic order quantity (EOQ) model incorporated with promotional effort cost, variable ordering cost and units lost due to deterioration Pages 57-66
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Authors: M. Pattnaik
DOI: 10.5267/j.uscm.2013.06.005
Keywords: EOQ; Deterioration; Units lost; Promotional effort cost; Variable ordering cost
Abstract:
This paper investigates the instantaneous economic order quantity model by allocating the percentage of units lost due to deterioration in an on-hand inventory by framing promotional effort cost and variable ordering cost. The objective is to maximize the net profit so as to determine the order quantity, promotional effort factor, the cycle length and number of units lost due to deterioration. For any given number of replenishment cycles the existence of a unique optimal replenishment schedule are proved and mathematical model is developed to find some important characteristics for the concavity of the net profit function. Numerical examples are provided to illustrate the results of proposed model, which benefit the retailer and this policy is important, especially for wasting of deteriorating items. Finally, sensitivity analyses of the optimal solution with respect to the major parameters are carried out.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 2 | Views: 3631 | Reviews: 0
14.
EOQ model for deteriorating items with exponential demand rate and shortages Pages 67-76
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Authors: H.S. Shukla, Vivek Shukla, Sushil Kumar Yadava
Keywords: Deterioration; Exponential demand; Inventory model; Shortages
Abstract:
In this paper, we develop an inventory model for deteriorating items with exponential time dependent demand rate. In this proposed model, shortages are allowed and partially backlogged. The model is explained with the help of numerical examples. We also show that total cost function is convex with time. Sensitivity analysis of the optimal solution with respect to various parameters of the system is given and results are discussed in details. Taylor’s series expansion is used for finding closed form optimal solution. Some results have been also obtained.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 2 | Views: 3520 | Reviews: 0
15.
Incremental analysis for the performance evaluation of material handling equipment: A holistic approach Pages 77-86
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Authors: Bipradas Bairagi, Balaram Dey, Bijan Sarkar
DOI: 10.5267/j.uscm.2013.06.003
Keywords: TOPSIS; MCDM; Material handling equipment; Incremental analysis
Abstract:
This paper addresses the application of group Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to Multiple Criteria Decision Making (MCDM), for assisting decision makers by evaluating, ranking and selecting material handling equipment (MHE). The present study considers engineering economy as one of the erudite tool for performance evaluation of said equipment in the integrated and synergetic way. Lastly, incremental analysis is used for final ranking of the equipment under inquisition.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 2 | Views: 30894 | Reviews: 0
16.
Determining the periodicity and planned lead time in serial-production systems with dependent demand and uncertain lead time Pages 87-98
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Authors: Haibatolah Sadeghi, Ahmad Makui, Heydari Heydari
DOI: 10.5267/j.uscm.2013.06.002
Keywords: Serial production systems; Planned lead time; Periodic order quantity Uncertainty; Supply chain
Abstract:
This paper considers a multi period serial production systems for one product and deals with the problem of planned lead-time calculation in a Material Requirement Planning (MRP) environment under probabilistic lead times. It is assumed that lead times for all stages have the same distribution with different parameters. A MRP approach with periodic order quantity (POQ) policy is used for the supply planning of components. The objective is to minimize the sum of fixed ordering, holding and backlogging costs. A mathematical model is suggested and then an optimal planning lead-time, ordering quantity and periodic time are determined.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 2 | Views: 2262 | Reviews: 0
17.
A mathematical model for a reverse logistic system of chemical remanufacturing PET waste with supply uncertainty: A case study of Tehran recycling organization Pages 99-106
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Authors: Fahimeh Mollaei, Ahmad Makui
DOI: 10.5267/j.uscm.2013.06.001
Abstract:
During the past two decades, there has been a growing concern on environmental issues around the world. Firms try to provide better production plans to recycle their used materials to reduce pollution from environment. In fact, lack of management in municipal solid waste for methods of collecting, disposal and processing of them can be significant damage to the environment, This paper presents a mathematical model for pet waste management, which plays essential role on municipal solid waste. The modeling formulation is a nonlinear probable mathematical programming model for chemical recycling the PET waste. In this model, the optimal amount of waste is determined by considering collected operations of reverse logistics and chemical recycling when demand is under uncertainty.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 2 | Views: 2441 | Reviews: 0
18.
A methodology for outsourcing resources in reverse logistics using fuzzy TOPSIS and fuzzy linear programming Pages 107-114
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Authors: Sajad Mehri, Emad Roghanian, Tahereh Khodadadzadeh
DOI: 10.5267/j.uscm.2013.05.004
Keywords: Supply chain; Fuzzy linear programming; Fuzzy TOPSIS
Abstract:
One of the primary concerns on supply chain management is to select appropriate suppliers based on different criteria, which are often in serious conflict. In this paper, we present a fuzzy TOPSIS technique to prioritize suppliers on reverse logistic network based on different criteria and then the proposed model of this paper applies fuzzy linear programming technique to determine optimum order quantity associated with each supplier. There are three criteria associated with each supplier including technical skills, equipment and ability to analyze. The implementation of the proposed method has been demonstrated in case study.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 2 | Views: 2342 | Reviews: 0
19.
Supply chain network optimization: A review of classification, models, solution techniques and future research Pages 1-24
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Authors: Niki Matinrad, Emad Roghanian, Zarifeh Rasi
DOI: 10.5267/j.uscm.2013.05.003
Keywords: Supply chain, Network, Optimization, Survey
Abstract:
With an ongoing progress in industries and technologies, most firms and businesses highly depend on cooperation and collaborations within a supply chain. In today’s competitive business environment, customer satisfaction plays an important role for the business survival. These matters can be secured by “supply chain”, a chain consists of various companies working together to maintain customers’ satisfaction. If various stages of different chains cooperate with each other, “supply chain network” (SCN) will be the outcome. In order to have a supply chain network or just a supply chain-operation in its best possible way, some optimization techniques are needed. In this paper, we present a close look at previous studies in the field of SCN optimization techniques and classify them based on the relative important characteristics.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 1 | Views: 7398 | Reviews: 0
20.
Supplier selection under uncertainty: A case study of home appliances maker Pages 25-32
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Authors: Tahereh Khodadadzadeh, Reza Vadayeh Kheiri, seyed jafar Sadjadi
DOI: 10.5267/j.uscm.2013.05.002
Keywords: Supplier selection, Supply Chain Management, Goal programming, Fuzzy programming
Abstract:
Many supply chain problems are involved with different parameters, which are under uncertainties. One of the primary concerns on supplier selection is to handle the uncertainty under different circumstances. The primary objective of this paper is to design a model to select suppliers and to determine the amount of purchase from any supplier in the supply chain system. For this purpose, we select the most important criteria using fuzzy questionnaires where the questionnaire uses experts’ opinions in terms of linguistic values. Then, a hierarchy multiple criteria decision-making (MCDM) model based on fuzzy-sets theory is proposed to rank different suppliers and using a goal programming approach, we determine the amount of order product from each supplier. The implementation of the proposed model is demonstrated using a real-world case study.
Journal: USCM | Year: 2013 | Volume: 1 | Issue: 1 | Views: 2798 | Reviews: 0