• Proceedings of the Korean Operations and Management Science Society Conference
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• 1991.10a
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• pp.116-123
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• 1991

사각 patch로써 곡면을 표현하는 일반적인 CAD/CAM시스템에서 NC가공을 위한 가공데이타를 생성할 때에는 보통 두가지 가공방법을 사용한다. 그 하나는 isoparametric가공이며 다른 하나는 cartesian가공이다. 금형부에서 사용하는 CAD/CAM시스템인 catia에서도 위의 두가지 NC가공방식을 모두 사용할 수 있다. 그런데 isoparametric가공의 경우, 공구간섭처리를 위한 곡면모델의 수정에 많은 시간이 소요되며, NC프로그래머의 실수로 인한 가공불량 발생의 가능성도 크고 황삭가공에도 매우 불편하다. 이러한 문제는 cartesian가공방법으로 해결이 가능하며, catia의 경우 parallel plane machining기능이다. 그러나 이 기능을 catia에서 통상적인 방법으로 modeling된 곡면에 적용할 경우에 그 신뢰성이 매우 낮다. 따라서 금형부에서는 그 방식은 cartesian으로 하되 신뢰성이 높은 NC가공 S/W를 개발하게 되었다. 이는 catia시스템에서 modeling된 곡면으로부터 NC 가공데이타를 생성하는 S/W로서 VS Fortran으로 작성되었다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2002.05a
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• pp.585-589
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• 2002

본 연구에서는 소프트웨어의 출시 이후 주기적인 보수(periodic maintenance)를 고려한 출시 시기 결정 방법을 제시하였다. 출시시기 결정방법에 관한 연구는 소프트웨어의 신뢰성 확보, 사용자 편의성 등에 관한 연구와 더불어 중요한 연구 분야로 여겨지는 분야이다. 일반 적으로 소프트웨어는 출시 이후에도 패치(patch), 서비스팩(service pack)등을 통해 지속적인 보수가 이루어지기 때문에, 출시 이후의 보수를 고려하여 출시시기를 결정하는 방법론이 필요하다. 이를 위해, 출시 이후의 보수정책을 반영한 소프트웨어 신뢰성 성장 모형(software reliability growth model)을 도출하였다. 위 모형을 기반으로 하여 비용과 신뢰성에 근거한 소프트웨어 출시 시점을 결정해 보았다. 제시된 모형의 타당성을 검증하기 위해 예제를 통해 기존의 논문에서 제시되었던 결과들과 비교분석을 해 보았다. 본 연구의 결과는 기존 연구에서 고려되지 않았던 보수 정책을 고려함으로써, 보다 현실에 가까운 모형을 제시하였다는 점에서 의의를 찾을 수 있고, 출시 후 보수 시점, 보수 정책 등의 결정에도 기여할 수 있을 것이다.

• Proceedings of the Safety Management and Science Conference
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• 1999.11a
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• pp.565-574
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• 1999

In reverse engineering area, it is rapidly developing reconstruction of surfaces from scanning or digitizing data, but geometric models of existing objects unavailable many industries. This paper describes new methodology of reverse engineering area, good strategies and important algorithms in reverse engineering area. Furthermore, proposing reconstruction of surface technique is presented. A method find base geometry and blending surface between them. Each based geometry is divided by triangular patch which are compared their normal vector for face grouping. Each group is categorized analytical surface such as a part of the cylinder, the sphere, the cone, and the plane that mean each based geometry surface. And then, each based geometry surface is implemented infinitive surface. Infinitive average surface's intersections are trimmed boundary representation model reconstruction. This method has several benefits such as the time efficiency and automatic functional modeling system in reverse engineering. Especially, it can be applied 3D scanner and 3D copier.

• Journal of Korean Society for Quality Management
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• v.39 no.2
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• pp.170-178
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• 2011

In general, a software fault detection phenonenon is described by a software reliability model based on a nonhomogeneous Poisson process(NHPP). In this paper, we propose a software reliability growth model considering the differences of the software environments in both the testing phase and the operational phase. Also, we consider the problem of determining the optimal release time and the optimal warranty period that minimize the total expected software cost which takes account of periodic software maintenance(e.g. patch, update, etc). Finally, we analyze the sensitivity of the optimal release time and warranty period based on the fault data observed in the actual testing process.

• Journal of the Korean Society of Radiology
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• v.84 no.2
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• pp.483-488
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• 2023

Iatrogenic injury of the vertebral artery during cervical spine surgery though uncommon is critical. With advances in interventional endovascular techniques, the therapeutic approach for vertebral artery injuries has changed. Nonetheless, an established strategy for their management is lacking. We report a case of pseudoaneurysm due to vertebral artery injury, during cervical spine surgery for a tumor, that was treated successfully with endovascular coiling in a plug-and-patch fashion after triple stenting failed.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2008.02a
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• pp.21-24
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• 2008

컴퓨터가 대중화 되면서 다양한 소프트웨어에 대한 수요가 증가하게 되었고, 많은 소프트웨어들이 단시간에 개발되어지고 있다. 이런 이유로 많은 소프트웨어들에 대한 취약점들이 생겨나게 되었고, 이를 해결하기 위해서 소프트웨어 벤더들은 패치를 만들고 배포를 하고 있다. 하지만, 다양한 시스템과 소프트웨어를 관리하는 곳에서 일일이 패치를 벤더로부터 받아 대상시스템에 설치하고 관리하기에는 어려움이 많으며, 일괄적이고 통합적인 방법이 필요하다. 이런 문제와 요구를 해결하기 위해 패치관리시스템에 관한 많은 연구들이 진행되어 왔으며 상용제품들도 하나둘씩 개발되고 있다. 하지만, 안타깝게도 많은 패치관련연구들이 안전한 패치관리시스템 설계나 구성에 관해서만 연구되고 진행되어 왔다. 안전한 패치관리시스템을 설계하거나 구성하기 전에 무엇보다도 우선시 되어야 하는 것이 필수적인 패치관리시스템 구성요소들을 정의하는 것이며, 이와 관련된 표준이나 연구가 많이 부족하다. 따라서 본 논문은 패치관리시스템을 구성하기 위한 기본적이면서 필수적인 구성요소들을 고려하고 정의했으며, 이를 바탕으로 기본 패치관리시스템 프레임워크를 설계했다.

• 한국생태학회:학술대회논문집
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• 2002.08a
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• pp.71-77
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• 2002

For landscape ecological management of the isolated forestlands in Incheon city located in the western tip of South Korea, the forest vegetation of Mt. Cheolma was classified phytosciologically and mapped out its spatial distribution at a scale of 1:5,000. Characteristics of forest landscape structures were discussed in terms of the number and size of patches obtained by analyzing vegetation map. Units to manage the forest vegetation were categorized into eighteen communities, seventeen groups, and sixteen subgroups. Landscape elements were classified into five types: secondary vegetation, introduced vegetation for forestry (IVF), introduced vegetation for agriculture (IVA), and other elements. Two hundred and ninety-three forest landscape patches covers 443.3ha of which IVF accounted for 316.8ha(71.5%), the largest portion, secondary vegetation for f01.2ha(22.8%), IVA for 6.2ha(1.4%), and others for 19.1ha(4.3%). The ratio of natural forest elements of 31.9% showed that this area was mainly comprised of artificially introduced vegetation, such as Robinia pseudoacacia plantation and Pinus rigida plantation. Forest landscape patches have a mean area of 4.5ha, a density of 66.1/100ha, and a diversity index of 0.87. It was estimated that differentiation of patches recognized in community level would be related to human interference and those in subordinate level to natural processes.

• The Korean Journal of Ecology
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• v.25 no.4
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• pp.205-211
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• 2002

For landscape ecological management of the isolated forestlands in Incheon city located in the western tip of South Korea, the forest vegetation of Mt. Cheolma was classified phytosciologically and mapped out its spatial distribution at a scale of 1:5,000. Characteristics of forest landscape structures were discussed in terms of the number and size of patches obtained by analy zing vegetation map. Units to manage the forest vegetation were categorized into eighteen communities, seventeen groups, and sixteen subgroups. Landscape elements were classified into five types: secondary vegetation, introduced vegetation for forestry (IVF), introduced vegetation for agriculture (IVA), and other elements. Two hundred and ninety-three forest landscape patches covers 443.3ha, of which IVF accounted for 316.8ha(71.5$\%$), the largest portion, secondary vegetation for 101.2ha(22.8$\%$), IVA for 6.2ha(1.4$\%$), and others for 19.1ha(4.3$\%$). The ratio of natural forest elements of 31.9$\%$ showed that this area was mainly comprised of artificially introduced vegetation, such as Robinia pseudoacacia plantation and Pinus rigida plantation. Forest landscape patches have a mean area of 4.5ha, a density of 66.1/100ha, and a diversity index of 0.87. It was estimated that differentiation of patches recognized in community level would be related to human interference and those in subordinate level to natural processes.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.3
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• pp.74-83
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• 2005

The Riparian Buffer Zone has many potential values including the preservation of water quality as well as being ecologically friendly. This study aims to quantitatively analyze the landscape structure index of the Riparian Buffer Zone in the Kyoung-an stream and to produce base information necessary for proper management. The study used aerial images that were applied to geometric corrections for a time series from 1966 to 2000 for land data and also used FRAGSTATS, which is a type of ARCVIEW extension module, as an analysis tool. An analysis of land use change and the Landscape Index revealed that the area of farm land has decreased and that the area of residential property has increased. In addition, there was a slight change for land used for purposes other than farming or for residence. The results of analyzing the Landscape Structure Index, revealed that the NP has increased from 437 in 1966 to 695 in 2000. This data reveals that the change of land use is influenced by various artificial factors. The NPS, which represents the declining degree of patch, decreased from 9.441 to 5.934, revealing that the change of land use has been progressing considerably. In regard to forest areas, land use reduced somewhat but did not indicate a significant change. Therefore, an analysis of the total index reveals that the edge of patch has become more complicated and that the variation index of patch has increased significantly. However, this study reveals that barriers to block pollution have weakened as a result and that there is a need to concentrate on the implementation and the management of the Riparian Buffer Zone. Consequently, this study reveals that substantial research is necessary in order to carry out the proper management of the Riparian Buffer Zone, especially in light of the distribution type of each patch and the change in conditions regarding them.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.104-108
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• 2006

Water extracts of Jehotang were evaluated for their growth-promoting effects on Bifidobacterium longum, Lactobacillus sp., L. acidophilus, and Clostridium perfringens. Addition of Jehotang water extract to modified EG media at 0.1 mg/mL increased growths of B. longum, Lactobacillus sp., and L. acidophilus, with 1.8-fold increase in growth of L. acidophilus compared to that of control. Studies on these strains by agar diffusion method showed Lactobacillus sp. and L. acidophilus were activated by addition of Jehotang extract at 10 mg/disc. Proliferation responses of mice splenocytes and Peyer's patch cells to ConA by LPS-stimulation at 500 mg/kg B.W./day Jehotang extract were investigated in vitro. Upon treatment of 1 mg/mL Jehotang water extract to mice, proliferations of splenocytes and Peyer's patch cells increased 1.4- and 1.6-fold compared to control, respectively. In mice administered Jehotang extract, production of intestinal secretory IgA (sIgA) increased 2.4-fold compared to control. These results indicate water extract of Jehotang stimulated intestinal immune system of mice. In mice treated with Jehotang extract, production of lymphocytes was 4% lower, whereas those of granulocytes and platelets were 4% and slightly higher than control, respectively.