Transnational companies, operating in extremely competitive global markets, always seek to lower different operating costs, such as inventory holding costs in their intra- supply chain system. This paper incorporates a cost reducing product distribution policy into an intra-supply chain system with multiple sales locations and quality assurance studied by [Chiu et al., Expert Syst Appl, 40:2669–2676, (2013)]. Under the proposed cost reducing distribution policy, an added initial delivery of end items is distributed to multiple sales locations to meet their demand during the production unit’s uptime and rework time. After rework when the remaining production lot goes through quality assurance, n fixed quantity installments of finished items are then transported to sales locations at a fixed time interval. Mathematical modeling and optimization techniques are used to derive closed-form optimal operating policies for the proposed system. Furthermore, the study demonstrates significant savings in stock holding costs for both the production unit and sales locations. Alternative of outsourcing product delivery task to an external distributor is analyzed to assist managerial decision making in potential outsourcing issues in order to facilitate further reduction in operating costs.

This study investigates the effect of random scrap rate on multi-item Finite Production Rate (FPR) model with multi-shipment policy. The classic FPR model considers production planning for single product, a perfect condition during the production run and a continuous inventory issuing policy. However, in real life manufacturing environments, in order to maximize machine utilization, vendors often make plan to produce m products in turn on a single machine. Also, in any given production run due to various different factors, generation of nonconforming items is inevitable. In this study, it is assumed that these defective items cannot be repaired, thus they must be scrapped with an additional cost and delivery of finished products is under a practical multiple shipment policy. Our objective is to determine an optimal common production cycle time that minimizes the long-run average cost per unit time and to investigate the effect of random scrap rate on the optimal common cycle time. Mathematical modeling is employed and renewal reward theorem is used to cope with the variable cycle length. The expected system cost for the proposed multi-item FPR model is derived and its convexity is proved. A closed-form optimal common production cycle time is obtained. A numerical example and sensitivity analysis is provided to demonstrate the practical use of the obtained results.

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In this paper, the bitstream parsing analysis and an efficient and flexible hitstream parsing processor are presented. The bitstream parsing analysis explores the critical part in bitstream parsing. Based on the result, the novel approaches to parse data partitioned bitstreams are presented. An efficient instruction set optimized for bitstream processing. cspecially for DCT coefficient decoding, is designed and the processor architecture can be programmed for various video standards. It has been integrated into an MPEG-4 video decoding system successfully and can achieve real time bitstream decoding with hitstream coded under 4CIF frame size with 30 fps, 8Mbps, which is the specification of MPEG-4 Advanced Simple Profile Level 5.

Data partitioning, one of the MPEG-4 video error resilience tools, enables better error robustness. However, it suffers from serious error propagation problem. In this paper, we use an experimental approach to model the error propagation with several commonly used error detection conditions. It is shown that errors detected in forward section of texture data may be propagated from motion data, while those in DCT coefficients mostly result from themselves. Furthermore, the motion marker is the major error source for several error conditions detected in motion part. According to these characteristics, motion marker assumption and backtracking-based concealment strategies are proposed to achieve more accurate error localization in bitstream domain.