• Journal of the Korean Operations Research and Management Science Society
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• v.22 no.4
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• pp.115-131
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• 1997

The problem addressed in this paper is to minimize the deviations of workloads assigned to worker and to maximize the total utilizations(degree of skill) between workers and machines simultaneously. Each worker can handle the set of machines with the different degree of skill and each machine has the workloads needed to be processed. Also, each worker has to be assigned to at least one machine with the minimum workload deviation. This problem can be formulated as a preemptive goal programming with generalized assignment constraints. The proposed algorithm consists of two phases. First, a capacitated circulation network is constructed to assign the workers to machines with the maximum total utilizations while considering workloads balance. Then, a refinement process is applied to the split machines to satisfy the feasibility condition. The real industrial application in a plastic extrusion manufacturer is included along with several computational experiments.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.224-225
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• 2000

Transparent and hard materials such as sapphire are used for many industrial applications as optical windows, hard materials on mechanical contact against abrasion, and substrate materials for opto-electronic semiconductor devices such as blue LED and blue LD etc. The materials should be cut along the proper shapes possible to be used for each application. In case of blue LED, the blue LED wafer should be cut to thousands of blue LED pieces at the final stage of the manufacturing process. The process of cutting the wafer is usually divided into two steps. The wafer is scribed along the proper shapes in the first step. It is inserted between transparent flexible sheets for easy handling. And then, it is broken and split in the next step. Harder materials such as diamonds are usually used to scribe the wafer, while it has a problem of low depth of scribing and abrasion of the harder material itself. The low depth of scribing can induce failure in breaking the wafer along the scribed line. It was also known that the expensive diamond tip should be replaced frequently for the abrasion. (omitted)

• Korean Journal of Head & Neck Oncology
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• v.32 no.1
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• pp.45-48
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• 2016

거대한 피부편평세포암은 드문 피부 종양이다. 편평세포암은 모든 피부 악성 종양 중 20%을 차지한다. 피부편평세포암은 주로 햇빛의 노출되는 것이 주요 원인으로 알려져 있으며, 때때로 피하층을 침범을 하는 경향이 있다. 편평세포암이 흔한 종양인 것과는 다르게, 5cm 이상의 거대 편평세포암은 보고된 바가 드물다. 이에 저자는 경부에 발생한 $14.5cm{\times}11.5cm{\times}9.5cm$ 크기의 거대한 피부편평세포암을 피부이식술을 통해 성공적으로 치료하여 이에 대해서 문헌 고찰과 함께 보고하는 바이다.

• KSBB Journal
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• v.23 no.1
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• pp.8-17
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• 2008

There are many different approaches to healing of acute and chronic ulcer and large skin defect, such as burn. Currently available wound covers fall into two categories. Permanent covering, such as autografts, and temporary ones, such as allograft including de-epidermized cadaver skin, bioartificial skin, xenografts, and synthetic dressings. Autologous skin grafting in the form of split- or full-thickness skin is still the good standard. Following on from developments in the 1980s involving the use of cultured keratinocyte grafts in wound healing, the last decade has been great progress in the fabrication of composite bioartificial skin grafts. However, two bottleneck on producing cultured bioartificial skin, whether of the simple epithelial cell sheet type, or the more complex composite type, continue to be the generation of sufficient keratinocytes cheaply and quickly and develop biocompatible dermal scaffolds. This article covers the development, clinical application, and current research directions associated with bioartificial skin.

• Journal of Energy Engineering
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• v.28 no.4
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• pp.13-18
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• 2019

The high energy penalty in amine-based post-combustion CO₂ capture process is hampering its industrial scale application. An advanced process is designed by intensive heat integration within the conventional process to reduce the stripper duty. The study presents the technical feasibility for stripper duty reduction by intensive heat integration in CO₂ capture process. A rigorous rate-based model has been used in Aspen Plus® to simulate conventional and advanced process for a 300 MW coal-based power plant. Several design and operational parameters like split ratio, stripper inter-heater location and flowrate were studied to find the optimum values. The results show that advanced configuration with heat integration can reduces the stripper heat by 14%.

• Proceedings of the KSEEG Conference
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• 2002.04a
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• pp.159-162
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• 2002

We tried to obtain an initial velocity model for prestack depth migration via waveform inversion. For application of any field data we chose a smooth background layered velocity model (v=v0 + k x z) as an initial velocity model. Newton type waveform inversion needs to invert huge Hessian matrix. In order to compute full Hessian matrix arising from full aperture data and full illumination zone, we meet insurmountable difficulties of paying astronomical computing cost. For the layered media, approximate Hessian emerging from single shot aperture data can be used repeatedly for split spread source configuration. In our work of using this Hessian characteristic of layered media we attempted to obtain the approximate velocity model as close as possible to the true velocity model in first iteration.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.590-592
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• 2003

The presence of congestion in transmission system can reduce the market size and split bulk system into smaller system. Consequently, this creates the problem concerining Local Market Power and can be main reason for the inclose of practical market price. In this paper, a range of indices have been derived to quantify the degree of local market power through statistical analysis in the uniform pricing market. Application of the indices has been illustrated using the electricity market in Korea. The indices proposed in this paper seem to be effectively applied in electricity market under uniform pricing scheme.

• Advances in concrete construction
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• v.3 no.2
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• pp.145-159
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• 2015

The evolution of nanotechnology provides materials with advance properties. It's a fast growing area of research to introduce the oxide nanoparticles into the cement pastes to improve their performance. The purpose of this paper is to review the effects of oxide nanoparticles (such as $SiO_2$, $TiO_2$, $Fe_2O_3$, $ZnO_2$, $Cr_2O_3$ and $Al_2O_3$) on both of hardened concrete properties (i.e., compressive strength, split tensile strength and flexural strength, water permeability, Abrasion resistance and pore structure of concrete) and fresh concrete properties (i.e., workability and setting time). Graphical representations of all these parameters were presented to facilitate the comparison of the effect of oxide nanoparticles on concrete processing. The paper also introduces some discussion about future work in this direction by identifying some open research area.

• Korean Journal of Plant Resources
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• v.7 no.1
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• pp.23-27
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• 1994

The growing condition and the point at issue were investigated for utilization as a fundamental data of the Boxthorn research in the growing farm household, which was chief producing district of Box-thorn in Chongyang, Chungmam province. The results were summarized as follow'; Lycium fruit wasproduced 445M/. in the 170.4ha. In practical cultivation, major numbers of decapitation were threetimes,, and planting distance was dense planting, and also amount of applied fertilizer was beyondbasic-fertilizer level and number of split application was abundant.Numbers of harvesting were six-ten times, and many labor was requiremented.The issues in cultivation were development of processing technique, supplement of varieties whichhave disease tolerance, superior quality and high yielding, improving of cultivation methods for laborsaving and magnification of demand.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.1
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• pp.43-50
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• 2005

The presence of transmission congestion may reduce the market size and split the bulk power system into smaller systems. Consequently, this can be a key factor to the increase in market price. This paper analyzes the effect of exercising local market power on the market price, and derives a range of indices which quantify the degree and incentive of local market power through statistical analysis in an electricity market with uniform pricing scheme. The applicability and effectiveness of the derived indices on competitive electricity markets are demonstrated on the Korea electricity market.