• Journal of Korean Institute of Industrial Engineers
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• v.35 no.2
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• pp.160-170
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• 2009

This paper studies a vehicle routing problem variant which considers customers to require simultaneous delivery and pick-up under time windows(VRPSDP-TW). The objective of this paper is to minimize the total travel distance of routes that satisfy both the delivery and pick-up demand. We propose a heuristic algorithm for solving the VRPSDP-TW, based on the ant colony system(ACS). In route construction, an insertion algorithm based ACS is applied and the interim solution is improved by local search. Through iterative processes, the heuristic algorithm drives the best solution. Experiments are implemented to evaluate a performance of the algorithm on some test instances from literature.

• Computational Structural Engineering
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• v.9 no.3
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• pp.157-167
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• 1996

A graphics system for optimum design(GOD) was developed for the various optimization programs. It is composed of a preprocessor and a postprocessor using the methods of pull-down and pop-up menus. The preprocessor of GOD system helps the designer to make a input file or a subprogram according to a selected optimization program. The postprocessor of the system display the numerical results generated during the iterative numerical analysis processes graphically in the graphic mode. Numerical examples as a mathematical linear problem and a 3-bar truss structure are presented to explain the use of GOD system. The system was programmed in one of the computer programming languages, Borland C.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.7
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• pp.163-172
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• 1996

Recently, it was reported that gaussian distribution and difference of two gaussians (DOG) to have band pass characteristics can be generated by simple iterative processes of the diffusion networks. In this paper, we propose method of improved implementation of a diffusion filter which can reduce total runing time, and operate by simple algorithm in contrast to the latest diffusion filter. We rebuild the diffusion network to a difference network which can generate DOG independently. Different filter characteristics are obtained just by each diffusion process and difference process. Quantitative analysis shows that the center frequency and the selectivity of each filter channel can be varied independently. Also, it would requires smaller amount of hardwares than conventioanl method to build a filter bank.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.1
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• pp.49-58
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• 2008

In this paper, we consider an inventory system where a single supplier purchases and processes raw materials into finished goods in order to deliver finished goods to a single buyer for effective implementation of Just-In-Time Purchasing. An integrated multi-item lot-splitting model of facilitating multiple shipments in small lots between buyer and supplier is developed in a JIT Purchasing environment. Also, an iterative solution procedure is developed to find the order quantity for finished goods and raw materials, and number of shipments between buyer and supplier. We show by numerical example that when the integrated policy is adopted by both buyer and supplier in a cooperative manner, both parties can benefit.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.11-17
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• 1999

The objective of this paper is to introduce very fast but still stable solution using finite element procedures, and it has been used in an iterative mode for product design applications. A lot of numerical techniques have been developed to deal with the material, geometric and boundary condition non-linearities occurred in the stamping process. One of them, the One-Step FEM is very efficient and useful tool for a design and trouble-shooting in various stamping processes. In this method, the mathod, the material is assumed to deform directly from the initial flat blank to the final configuration without any intermediate steps. The formulation is based on the deformation theory of plasticity and the upper bound theorem. As a result of the calculations, the initial blank shape is obtained, together with the material flow, strains and thickness distribution in the part.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.6
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• pp.49-57
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• 1993

In the paper, we describe the design of a pipelined datapath synthesis system for DSP applications. Taking SFG (Signal Flow Graph) in schematic as inputs, the system generates pipelined datapaths automatically through scheduling and module allocation processes. For efficient hardware synthesis, scheduling and module allocation algorithms are proposed. The proposed scheduling algorithm is of iterative/constructive nature, where the measure of equi-distribution of operations to partitions is adopted as the objective function. Module allocation is performed to reduce the interconnection cost from the initial allocation. In the experiment, we compare the results with those of other systems and show the effectiveness of the proposed algorithms.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.4
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• pp.25-34
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• 2011

In this paper, we investigate an inventory system where a single manufacturer purchases and processes raw materials in order to deliver finished goods to multiple retailers. Earlier study in this type of supply chain only consider a single raw material in order to produce finished goods, but we consider multi-raw materials in order to produce finished goods. Also, we develop an iterative solution procedure to find the order quantity for the finished goods and raw materials, and the number of shipments between manufacturer and retailers that minimizes the total cost per unit time of the raw materials ordering and holding, manufacture's setup and finished goods holding, the retailer's ordering and inventory holding. Numerical examples are presented to illustrate that jointly considering the total cost results in less total cost than that of considering them separately.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.26 no.3
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• pp.50-57
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• 2003

In this paper, we consider an integrated inventory system where a single supplier purchases and processes raw materials in order to deliver finished goods to a single buyer for effective implementation of Just-In-Time purchasing. An integrated JIT lot-splitting model of facilitating multiple shipments in small lots is developed in a JIT purchasing environment. Also, an iterative solution procedure is developed to find the order quantity for the finished goods and raw materials, and the number of shipments between buyer and supplier. We show by example that the integrated policy adopted by both buyer and supplier in a cooperative manner can provide them a greater economic benefit than seeking the local optimal inventory policy independently.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.12 no.19
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• pp.31-37
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• 1989

The recursive residuals are obtained by the iterative processes as descrbed in section 2. They may require more efforts and time to compute and may face difficultie in ordering of data. But we can investigate each case to be deleted and gather more informations on each case. The recursive residuals are much more effective with conjecture of cusum technique. We suggest to use the predicted residual for the construction of recursive residuals in nonlinear regression models. The assessment of influence and leverage by the connection with recursive residuals will be necessary.

• Journal of the Ergonomics Society of Korea
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• v.14 no.2
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• pp.63-73
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• 1995

An approach to quantitative evaluation of product usability during the design and implementation phases of the product life cycle is presented. The evaluation starts by defining a set of usability characteristics, viz. physical, cognitive and affective characteristic. Each of these characteristics is assessed by a set of usability criteria, such as functionality, visual clarity, learmability, etc. The usability criterion is then evaluated by a checklist consisting of a detailed questionnaire. The fuzzy weighted-checklist method with linguistic variables is used for quantitative analysis. Also, the method for quantifying usability improve- ments in iterative design processes is considered. This analysis procides a quantit- ative measure, which reflects the degree of excellence of product usability during the design and development phases.