• IE interfaces
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• v.13 no.2
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• pp.217-224
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• 2000

This paper analyzes the effects of setup cost reduction in a dynamic lot-sizing model for a single-facility multi-product problem. In the model, demands for each product are known, no backlogging is allowed, and a single resource is employed. Also, setup cost is defined as a function of capital expenditure to invest in setup cost reduction. Furthermore, in each production period the facility (or plant) produces many products, each representing a fixed part of the involved production activity (or input resource quantity). In this paper, the structure of the optimal solution is characterized and an efficient algorithm is proposed for simultaneously determining the optimal lot size with reduced setup cost and the optimal investment in setup cost reduction. Also, the proposed algorithm is illustrated by a numerical example with a linear and an exponential setup reduction functions.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.2
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• pp.124-129
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• 2011

The thick plate produced by rolling process is used as the basic members of a ship structure. In this paper, we present a setup model to control the asymmetric factors causing plate bending in the upper or lower direction during rolling. A series of finite element analysis are conducted to predict the relationship between various asymmetric factors and plate bending. The setup model is developed by regressing the relationship to the linear equations with several non-dimensional parameters. The setup model is verified by a pilot rolling test and applied to actual rolling conditions. Results show that the model is substantial to predict the asymmetric deformation in the plate rolling process.

• Management Science and Financial Engineering
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• v.3 no.1
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• pp.57-74
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• 1997

An EOQ-like inventory model for a manufacturing process is studied. The system is assumed to deteriorate during the production process. The results are either the production of a number of defective items, or the breakdown of the production machine. The optimal production lot size is derived. The model is extended to the case in which the probabilities of making defective items and machine breakdowns are a function of both the quantity (amount) and quality (performance) of the consumed setup cost (including the preventive maintenance cost). We further assume that the setup performance can be improved by investing in the performance improvement program. Hence, the same or a better setup outcome can be achieved with a lower setup cost. We then investigate the optimal setup cost and investment policy simultaneously, thereby achieving a better process quality and setup cost reduction concurrently.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.2
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• pp.251-256
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• 2006

In this paper we consider multi-stage, multi-product production, inventory systems which have assembly-tree-structure. We propose a new mathematical model for pull type ordering systems based on JIT manufacturing systems. To apply the model to an actual automobile parts manufacturer, the objective of proposed model is to minimize the sum of inventory and setup costs. Finally, a numerical example and computational results are given to illustrate the proposed model.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1437-1443
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• 2011

Thick plates produced by the rolling process are used as the basic elements of ship structures. In this paper, we present a setup model for controlling the asymmetric factors causing plate bending in the width direction during plate rolling. A series of three-dimensional finite element analyses is conducted to predict the relationship between various asymmetric factors and plate bending. The setup model is developed by performing regression on the relationship to produce linear equations with several nondimensional parameters. The setup model is verified with a pilot rolling test in which variations in thickness and temperature differences in the width direction exist. The results show that the bending curvatures predicted by the model are in fairly good agreement with the measured results for those asymmetric factors.

• Proceedings of the KIEE Conference
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• 1998.11b
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• pp.630-632
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• 1998

The basic user location strategies proposed in current PCS(Personal Communication Services) Network are two-level Database strategies. These Databases which exist in the Signalling network always maintain user's current location information, and it is used in call setup process to a mobile user. As the number of PCS users are increasing, this strategies yield some problem such as concentrating signalling traffic on the Database, increasing Call setup Delay, and so on. In this paper, we proposed RCP(Reverse Connection setup Protocol) model, which apply RVC(Reverse Virtual Call setup) algorithm to PCS reference model, and CRCP(Cache algorithm in RCP) model, which adopt Caching strategies in the RCP model. When Cache-miss occur, we found that CRCP model require less miss-penalty than PCS model. Also we show that proposed models are always likely to yield better performance in terms of reduced Location Tracking Delay time.

• Transactions of Materials Processing
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• v.23 no.1
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• pp.16-22
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• 2014

The current study presents a simple setup method for making teeth models using a three-axis CNC milling machine. Physical teeth models can be made by several methods: casting, machining, and three-dimensional printing. Since the shape of a teeth model requires five-axis machining, the machining of a teeth model using a three-axis CNC milling machine requires careful setup operations. In this paper a simple datum shape is designed within the work piece of the teeth model. The datum shape is an n-sided prism with regular n-polygon ends and rectangular sides. In the present study a 12-sided prism is used, which easily makes 30 degree rotations for finish machining. The proposed setup approach does not require any special tools for making the teeth model using a three-axis CNC milling machine. A test was run and the results show that the proposed approach is useful for experimental makings with the limited facilities available.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.8 s.251
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• pp.957-964
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• 2006

As the requirement of LCD products which are large screen and have high brightness increases, the role of light guide panel (LGP) of which micro-features diffuse the light uniformly on surface is getting important. In general, there are many errors in machining like machine tool errors process error, setup error and etc. The amount of setup error in general machining is not so big in comparison with the others, so it is mostly neglected. But, especially in v-groove micromachining, setup error has a significant effect on micro-features. Low quality product and high cost are resulted from setup error. In v-groove micromachining, to confirm the effect of setup error, it is identified and then setup error synthesis model is derived from analysis of tool and workpiece setup. In addition, to predict the micro-features affected by setup error and enhance the production efficiency, the setup condition satisfying the tolerance of micro-features is geometrically analyzed and presented.

• Management Science and Financial Engineering
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• v.4 no.2
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• pp.15-42
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• 1998

A joint problem of order delivery, setup reduction, and cost-sharing in a two-echelon inventory system in which a vendor supplies multiple products to a group of buyers is studied here. The basic premise is that buyers have independently implemented setup reduction programs to acquire benefits from small order sizes. Doing so, however, causes the buyers' individually optimal order cycles to be differ from that of the vendor. In conjunction with this, two models are considered. In the first model, a multi-buyers single product situation is considered in which the vendor implements a joint supply cycle policy. However, buyers, as the dominant party, insist after implementing the individually optimal setup reduction that the vendor accept their individually optimal order schedules. In the second model. a multi-products, single buyer situation is considered in which the buyer implements a joint order policy. Here, the vendor, as the dominant party, refuses to cooperate fully with the buyer's individually reduced joint order schedule, and designs his own individually optimal setup reduction mix for each product under a given budget constraint. This led to a study of an integrated Setup Reduction/Break-even Pricing Policy for each situation to eliminate mismatches in individually optimal cycle times.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.3
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• pp.95-108
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• 2013

The problem of constrained sequencing of a set of jobs on a conveyor system with the objective of minimizing setup cost is investigated in this paper. A setup cost is associated with extra material, labor, or energy required due to the change of attributes in consecutive jobs at processing stations. A finite set of attributes is considered in this research. Sequencing is constrained by the availability of conveyor junctions. The problem is motivated by the paint purge reduction problem at a major U.S. automotive manufacturer. We first model a diverging junction with a sequence-independent setup cost and predefined attributes as an assignment problem and this model is then extended for a more general situation by relaxing the initial assumptions in various ways.