• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.3
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• pp.27-46
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• 1992

This paper considers an (r, Q) policy for operation of a multipurpose facility. It is assumed that whenever the inventory level falls below r, the model starts to produce the fixed amount of Q. The facility can be utilized for extra production during idle periods, that is, when the inventory level is still greater than r right after a main production operation is terminated or an extra production operation is finished. But, whenever the facility is in operation for an extra production, the operation can not be terminated for the main production even though the inventory level falls below r. In the model, the demand for the product is assumed to arrive according to a compound Poisson process and the processing time required to produce a product is assumed to follow an arbitary distribution. Similarly, the orders for the extra production is assumed to accur in a Poisson process are the extra production processing time is assumed to follow an arbitrary distribution. It is further assumed that unsatisfied demands are backordered and the expected comulative amount of demands is less than that of production during each production period. Under a cost structure which includes a setup/ production cost, a linear holding cost, a linear backorder cost, a linear extra production lost sale cost, and a linear extra production profit, an expression for the expected cost per unit time for a given (r, Q) policy is obtained, and using a convex property of the cost function, a procedure to find the optimal (r, Q) policy is presented.

• Journal of the Korea Safety Management & Science
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• v.19 no.1
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• pp.181-189
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• 2017

The systematic management of technology infrastructure increasingly becomes critical as it represents the driving power for creating competitive advantage of nations and enterprises. In this sense, public facility and equipment, which is one major asset of technology infrastructure, should be managed effectively, systematically and efficiently to increase its overall equipment effectiveness. However, the manual and off-line communication was the unique way to communicate between the suppliers who provide facilities in the public sector and the customers who utilize the facilities in the industrial sector. This communication way caused invisibility of available usage time and increase of idle time, thereby decreasing the equipment effectiveness. This paper presents an web-based scheduling system that enables real-time collaboration and information sharing for increasing the equipment effectiveness. The designed system performs scheduling, facility management, order management and customer relationship management in an on-line platform, and carries out the processing and storing of relevant information in an integrated database. The paper includes a development approach to identify business process models and standardized system models by using object-modeling technique. The deliverable of the present work will contribute to increasing the equipment effectiveness by enhancing visibility, transparency and predictability by means of the integration with a legacy Enterprise Resource Planning.

• Journal of the military operations research society of Korea
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• v.30 no.1
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• pp.48-69
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• 2004

An optimal allocation model for SAM-X by using a set covering model is suggested. This allocation model considers to guarantee the maximum security of vital areas from the attack of enemy aircraft(s) and missiles. In order to formulate this model, we applied the concept of parallel structure reliability to set covering model. This model gives both direction of the primary target line and location of the facility. When applied this model to the real situation, the solution of this model can be used to the references of decision making for the optimal military facility allocation.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.119-123
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• 2010

Causes of the levee collapse are directly or indirectly associated with geotechnical engineering as well as hydraulics. In this paper, literature survey and analysis were conducted to present the alternatives in geotechnical engineering issues for rational levee design. The alternatives include the reasonable river-bed soil utilization and precautions of numerical analysis and slope stability analysis, disruption type and improvement method of drainage facility.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.10a
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• pp.45-48
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• 1996

The most research on facility layout problems ignored the actual shape of building where the activities(departments) are to be arranged. They also ignored the aisles between departments inside the building. In this paper, we present a genetic algorithm that searches a very good facility layout with horizontal aisles for two different cases with respect to the department shape. From the extensive experiments, the proposed genetic algorithm generated better layouts than the ones obtained by applying Tam's algorithm. It showed about 10% improvement of performance. We found out the best combination of genetic operators through the experiments.

• Journal of the Korean Operations Research and Management Science Society
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• v.10 no.2
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• pp.15-23
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• 1985

A multi-product multi=facility production planning model is in which known demands must be satisfied. The model considers concave production costs and piecewise concave inventory costs in the introduction of production capacity constraints. Backlogging of unsatisfied demand is permitted. The structure of optimal production schedules is characterized and then used to solve an illustrative numerical problem.

• Journal of the Korean Operations Research and Management Science Society
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• v.21 no.2
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• pp.59-70
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• 1996

Given the flow matrix, plant size (rectangle shape) and department sizes, the algorithm in this paper provides the plant layout with rectilinear distance measure. To construct automated facility design, eigenvector approach is employed. A branch and bound computer code developed by Tillinghast is modified to find the feasible fits of departments without shape distortion (see [1])in the plant rectangle. The computational results compared with CRAFT are shown.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.122.1-122.1
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• 2011

We propose a program of conducting research of young supernovae in nearby galaxies using the KMTNet facilities. Thanks to the wide field ($2^{\circ}{\times}2^{\circ}$) with multiple filters and the continuous sky coverage using the three 1.6 m telescopes, the KMTNet can provide an unprecedented opportunity for studying supernovae. The primary program is twofold: it can be used as a discovery facility of young supernovae and also as a facility providing multi-band photometric data of unprecedentedly high cadence for supernovae light curves.

• Journal of the Korean Operations Research and Management Science Society
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• v.31 no.4
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• pp.139-155
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• 2006

The facility location problem of this paper is distinguished from the maximal covering location problem and the flxed-charge facility location problem. We propose the maximal profiting location problem (MPLP) that is the facility location problem maximizing profit with multi-product. We apply to the simulated annealing algorithm, the stochastic evolution algorithm and the accelerated simulated annealing algorithm to solve this problem. Through a scale-down and extension experiment, the MPLP was validated and all the three algorithm enable the near optimal solution to produce. As the computational complexity is increased, it is shown that the simulated annealing algorithm' is able to find the best solution than the other two algorithms in a relatively short computational time.

• Journal of the Korean Operations Research and Management Science Society
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• v.29 no.3
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• pp.63-78
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• 2004

This paper deals with a supplier-managed inventory(SMI) control for a two-echelon supply chain model with a service facility and a single supplier. The service facility is allocated to customers and provides a service using items of inventory that are purchased from the supplier, Assuming that the supplier knows the information of customer queue length as well as inventory position in the service facility at the time when it makes a replenishment decision, we identify an optimal replenishment policy which minimizes the total supply chain costs by reflecting these information into the replenishment decision. Numerical analysis demonstrates that the SMI strategy can be more cost-effective when the information of both customer queue length and inventory position is shared than when the information of inventory position only is shared.