• Journal of Korean Society for Quality Management
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• v.40 no.1
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• pp.88-91
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• 2012

Joint optimization of preventive age replacement and inventory policy is considered in this paper. There are three decision variables in the problem: (i) preventive replacement age of the operating unit, (ii) order quantity per order and (iii) reorder point for spare replenishment. Preventive replacement age and order quantity are jointly determined so as to minimize the expected cost rate, and then the reorder point for meeting a desired service level is found. A numerical example is included to explain the joint optimization model.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.2
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• pp.170-175
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• 2010

Maintaining a complex repairable system can be achieved by repairing, replacing, or any other activities. This paper proposes a joint optimization policy that is composed with ordering and replacing under minimal repair for the complex system. For this purpose, we derive the expected cost due to the minimal repair, ordering, downtime, inventory costs, and salvage value of units that follow generally distribution. Some properties about the optimum ordering policy that are suggested for our purpose shows that the optimum ordering policy minimizing the expected cost is either one of the two typical policies : (1) the original unit is replaced as soon as the ordered spare is delivered, or (2) the delivered spare is used as inventory part until the original unit fails.

• Archives of Plastic Surgery
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• v.50 no.5
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• pp.501-506
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• 2023

This article portrays the authors' experience with a complex lower limb bone and soft tissue defect, following chronic osteomyelitis and pathological fracture, which was managed by the multidisciplinary orthoplastic team. The decision for functional amputation versus limb salvage was deemed necessary, enhanced by the principles of "spare parts" in reconstructive microsurgery. This case describes the successful use of the osteocutaneous distal tibia turn-up fillet flap that allowed "lowering the level of the amputation" from a through knee to a below-knee amputation (BKA) to preserve the knee joint function. We comprehensibly review reports of turn-up flaps which effectively lower the level of amputation, also applying "spare-parts" surgery principles and explore how these concepts refine complex orthoplastic approaches when limb salvage is not possible to enhance function. The osteocutaneous distal tibia turn-up fillet flap is a robust technique for modified BKA reconstructions that provides sufficient bone length to achieve a tough, sensate stump and functional knee joint.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.289-299
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• 2020

The composition of convergence cross-section of the material is a technique that provides reasonable design and construction of structures. It is frequently used in medium-sized bridges and architectural structures. However, the structural behavioral spare capacity enhancement of the structure by the application of the convergence cross-section is still limited by the expandability due to the limiting state of each material. In order to overcome these limitations, this study reasonably analyzed the construction stages before and after the convergence cross-section constructed and developed a technique for forming multi-point boundary conditions using struts, which are compression members. Based on the existing cases, a reasonable construction step for forming the material composite section of the entire structural system of the structure was derived, and a numerical analysis model for a specific part was constructed to analyze the behavior of the strut application. As a result of this study, the effect of reducing the sectional force of 7.40% in beam-column joint and 6.31% in the center of girder was derived, and the deflection, which is a measure of the serviceability of the structure, improved by 54.41% from the installation and dismantling of strut members at each construction stage.

• Archives of design research
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• v.12 no.2
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• pp.31-40
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• 1999

Because of the oocIear family due to the rapid industrialization and the growth of husband and wife bah working, the base of the tradition that the parents, all of the famly or the hamet oonmunity bring up the infants together in the important time to the infarts has been collapsed in Korea. Because working mothers camot bring up their children by themselves they got stressed and housewives do not have the oonfidence in rearing their infants and the fathers are isolated from home and the chikten instead of being exempted from the responsibility of rearing children. Therefore the common and comprehensive rearing system should be made for solving the child-rearing problem. For solving these problems and for the desirable infant-rearing and education, the joint irlart rearing, whidl compensates for the life, education and furthermore the sdlool edJcation through the volur1ary participation, has been prepared altematively. Compared to the traditional rearing system, joint infant-rearing is not only operated by the residents with the dues paid by the union members but also makes children experience the life force of natu"e in themselves. So the preparation of the standard of the suitable environment design for the joint infant-rearing is required which is diffrent from the traditional standard of the environmertal facilities for the traditional rearing system. The concept of joint infant-rearing was defind in this study through the reference and the ooncept of infant edJcation which is in operation suocessfully in Italy and Sweden in order to understand how the ooncept of infant education has changed as the ages have dlanged. And the basic principals for the formation of physical envirorvnert and the spare design and the envirorYnertal oondition for the practical environmental design was also studied through the reference. And after study about the concept. figure and physical environmental suggestion, the concept, standard and element of joint infant-rearing environment design was suggested. And as the final conclusion, the design requirement of the envirorvnertal design for the joint infant-rearing was suggested.

• Journal of Korean Association for Spatial Structures
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• v.14 no.3
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• pp.101-108
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• 2014

Recently, natural disasters such as earthquake, tsunami, typhoon and tornado are increasing, and cause huge economical loses and victim. Thus, when the disaster occurs, it is important to prepare emergency evacuation shelters for fast and easy construction compared to general building system. And, deployable structures will provide a great help for such aim. Deployable structures have the great advantage of being faster and easier to erect and dismantle compared to conventional building forms. In this study, we confirm the possibility of deployment for shelter structures using scissor structure system. First, Basic model was performed to recognize the appllicability of the deployable systems of the dome-shaped structure. Second, Advanced model that more improved inner space and deployment mechanism was confirmed.