This research paper aims to investigate operational performance and potential factors that constitute efficient supply chain operational performance in different countries, namely, Japan, Thailand and China. By analyzing the supply chain performance, the supply chain management (SCM) logistics scorecard (LSC) has been utilized as a self-evaluation tool for participating companies in the above-mentioned countries. The LSC focused on four decisive areas, namely, company strategy, planning and execution capability, logistics performance, and IT utilization. The number of participating companies from each country was 205 from Japan, 105 from Thailand and 107 from China. The scores in each assessment area were compared among countries. Subsequently, in this research study, a factor analysis was conducted using the result of the LSC in order to identify significant factors that represent the operational performance of SCM in each country. The results of the factor analysis indicate that the structures for generating successful SCM in Japanese, Thai and Chinese industries are not the same due to different operating environments.

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In this study we first present a decision approach for the optimal input quantity of new part in a remanufacturing system that considers product lifecycle (PLC)(Proposal 1). Next, we discuss the utility of a service network for the collection and disassembly (NCD) of reusable products with PLC or a part with PLC received from a customer or an internal production process, and present a decision approach for the optimal input quantity of a new part in a remanufacturing system that considers PLC (Proposal 2). In Proposal 2, it is assumed that by paying a commission fee to the NCD, both more used products and more defective units (parts or finished products) will be taken back more smoothly from the customer/each production process, disassembled more rapidly, and the parts will be reused as spare parts in each production process. It is expected that the remaining quantity of reusable part will increase due to the reduction of lead-time in the collection and disassembly process using NCD. In numerical experiments, the utility of NCD in a remanufacturing system considering PLC is investigated. The input quantities of both new parts and reusable parts for each production process, and the expected minimal total operating cost for the remanufacturing system when using NCD are compared with that when not using NCD.

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Finite Capacity Scheduling(FCS) has a major drawback because it is difficult to calculate the necessary capacity adjustment for each day and for each work center. To overcome this shortcoming, the authors have developed the Squeezing Method. A key element of this method is the compression coefficient. When backward scheduling is used and the start times of orders go back to past dates, the compression coefficient reduces the lead time of the total operation. This "squeezing" is necessary when the arrival work-load level is above a certain amount. The arrival load ratio at which it becomes necessary to compress the lead time to avoid delays is defined in the study as the marginal arrival load ratio. Finally, the authors present an equation for estimating the optimum compression coefficient for a given simulation model. Using the equation, the optimum compression coefficient can be determined and the capacity increase requirements per day and per work center can be calculated.

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The joint replenishment problem (JRP) involves determining a replenishment policy that minimizes the total cost of replenishing multiple items from a single supplier. In this paper, we propose a new approach for the JRP where items are procured from multisupplier. In solution algorithms, the Genetic Algorithm (GA) and the Simulated Annealing (SA) are cooperatively used. In this method, the convergence of GA is improved by introducing the probability of SA as the criterion for acceptance of new trial solution. We use genetic algorithm for this problem. The purpose of the proposed algorithm in this paper is to minimize the total relevant costs per unit time. The effectiveness of the proposed algorithm is shown through a simulation study.

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The purpose of the implementation of Theory of Constraints (TOC) concepts in cell manufacturing scheduling is to introduce an alternative that generates a better total makespan of a cell based on a flow-shop production system, while analyzing also the labor productivity of the system. The drum-buffer-rope (DBR) cell algorithm is compared to a schedule based on a random rule to determine its efficiency by evaluating different system sizes. The results show that the DBR-cell algorithm performs better under a system with a small number of resources. This can be considered a consequence of the difficulty to determine a single resource as a constraint in larger systems. Furthermore, productivity also becomes larger in comparison with random scheduling as a system's size increases in terms of jobs.

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The role of IS (Information Systems) auditing is becoming increasingly important because IS auditing is one of the most important components of IT governance and corporate governance. Therefore, IS auditors should be able to explain the audit process, their objectivity and conclusions of the audit. The audit process is based on risk assessment. Auditors should assess various kinds of IS risks, for instance, effectiveness risk, efficiency risk, compliance risk, legal risk, confidentiality risk, availability risk and integrity risk. Risk assessment consists of impact assessment and probability assessment. But auditors cannot make precise assessments of impact and probability, because there are no common measures for assessing the risk. In this paper, we discuss a risk assessment method that analyzes various kinds of risks using AHP (Analytic Hierarchy Process). Auditors can assess various kinds of risk using AHP, and they can explain their risk assessment results numerically. The proposed approach contributes to improving the audit process. Numerical results based on the actual data are given to show the usefulness of the methodology.

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The resource-constrained project scheduling problem (RCPSP) is one of the most difficult challenges in project schedule management. In the previous research work for RCPSP, activity durations in the project are often initially determined by the fixed values (fixed activity durations), and then the optimization process is carried out to assign the optimal start times of activities. In many cases, however, the activity durations vary within the certain ranges (variable activity durations), and depend on the scheduling objective. Thus, it is highly probable that these initially fixed activity durations lead to unexpected results. The way in which the activity durations are reasonably assigned is very important for reducing the overall project duration under resource constraints. For solving the RCPSP with variable activity durations, it is impossible to use the traditional methods (such as CPM, PERT), so the new method based on genetic algorithm (GA) is proposed in this paper for solving the problem. In the proposed method, the genetic algorithm is introduced to determine the optimal activity durations, and the heuristic rules are applied to assign the optimal start time of each activity so that the overall project duration under resource constraints is minimized.

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The widescale retirement of Japanese workers in 2007, known as the "2007 Problem," will precipitate the loss of an unprecedented amount of intellectual capital from the Japanese workforce, threatening the future viability of many organisations. The use of information and communication technology (ICT) has been proposed as a tool to support knowledge-retention management techniques, however, many seniors reject ICT use. This paper discusses the conceptual framework and basic architecture of an ICT skills course directed at seniors (PASOLEARN), underpinned by a pedagogical model that seeks to meet and sustain seniors' 'intrinsic motivation.' E-learning was chosen as the platform for PASOLEARN because of its capacity to reach older people precluded from 'bricks-and-mortar' classes by distance, lack of transport or physical infirmity, and also because of the 'self-education' freedom it gives older people with a low sense of efficacy in ICT education. Based on a survey conducted at Kanazawa City's 'Ikigai IT Centre' (IIC), an ICT education facility for Kanazawa residents aged over 55, we found that the PASOLEARN contents impacted IIC members' motivation levels and perceived effectiveness and usefulness of the course. It also revealed gender-based differences in motivation levels.

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