• KSTLE International Journal
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• 제4권1호
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• pp.8-13
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• 2003

Abrasion in fretting wear mechanism is studied experimentally with the specimens of two different shapes of spacer grid spring and fuel tubes of a nuclear fuel. Reciprocating sliding wear test has been carried out in the environment of air and water at room temperature. Especially, third body abrasion is referred to for explaining the wear region expansion found during the slip displacement increase with constant normal contact farce. It is found that the expansion behaviour depends on the contact shape. The small clearance between the tube and spring seems to be the preferable region of the wear particle accumulation, which causes third body abrasion of the non-contact area. Even in water environment the third body abrasion occurs apparently. Since the abrasion on the clearance contributes wear volume, the influence of the contact shape on the severity of third body abrasion should be considered to improve the grid spring design in the point of restraining wear damage of a nuclear fuel.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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• pp.862-868
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• 1998

Korean Next Generation Reactor(KNGR) is a standardized evolutionary Advanced Light Water Reactor design under development Korea Power Company(KEPCO). It incorporates design enhncements such as active and passive advanced design features(ADFs) to increase the plant safety. A Preliminary level 1 Probabilistic Safety Assessment(PSA) has been performed for KNGR to examine the effect of these safety features. The preliminary PSA result shows that it meets the KNGR safety goal on core damage frequency(CDF). The result of this safety assessment shows that the four-train safety systems, and the ADFs such as Passive Secondary Cooling System (PSCS) contributes greatly to the reduction the CDF. Furthermore, several design changes are made or proposed for detailed review based on the PSA insights.

• KEPCO Journal on Electric Power and Energy
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• 제2권1호
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• pp.55-59
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• 2016

In Europe, polypropylene-insulated HV class cable with high temperature and no cross-linking was commercialized following the MV class. Our company also started a study of the polypropylene-insulated cable in 2013 and was carried out thermal, physical and electrical test. In addition, polypropylene-insulated cable was tested for compatibility with conventional joints and terminations in emergency condition and the accelerated life test for verifying their design life is in progress. The results of this study will be used to establish a standard specification and operation conditions of the polypropylene-insulated cable.

• 지능정보연구
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• 제17권1호
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• pp.91-110
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• 2011

본 논문은 호텔 관광 서비스 업계에서 급변하는 전산화와 글로벌화에 대응하기 위하여 IT 솔루션 도입을 통하여 기업의 업무 처리를 고도화하고 고객 서비스 대응력을 높인 사례를 연구하였다. 이를 통하여 국내 유수의 호텔 관광기업이 효과적으로 고객 요구에 대응하기 위하여 CRM 솔루션을 자체적으로 개발하여 실무에 활용하도록 함으로써, 고객에 대한 분석력을 높이고 고객별 마케팅 전략 수립과 고객에 특화 한 영업을 전개하는 활용 사례를 연구하였다. 특히 본 연구는 호텔 관광 업계의 CRM 솔루션 도입 과정과 CRM을 이용한 영업 업무 및 마케팅 업무에 활용해 나가는 과정에 대하여 논하였고, CRM 도입에 의한 효과를 DEA(Data Envelopment Analysis) 를 통하여 분석하였다. 우선 CRM을 도입한 L사의 각 사이트별 상대적 효율성을 CCR 모형으로 비교 분석하였으며, 그 다음 L사의 대표 사이트에 소속된 각 영업장들의 상대적 효율성을 BCC 모형으로 비교 분석하였다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.597-601
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• 2006

건설생산 프로세스의 각 단계에서 자재 관련 정보의 신속한 검색 및 활용 체계가 미비하여 각종 자재의 분석 및 선정에 상당한 인력 및 시간이 소요되고, 또한 각 단계별로 작성된 중요 정보들의 재활용 체계도 미비하여 각 단계별 업무 및 현장 종료 시 사장되고 있다. 그 결과 각 단계에서 유사/동일 업무의 반복수행으로 회사차원에서 인적자원의 효율적 운용을 저해하고 회사 경쟁력을 저하시키는 주요인이 되고 있는 실정이다. 또한 개설현장에서 마감자재 선정 시 제품특성과 현장 적용사례 등 깊이 있는 기술정보가 부족하여 자재선정에 많은 애로가 있으며, 시공품질은 물론 현장 손익에 지대한 영향을 주게 됨에 따라 마감자재 관련 현장사례 정보를 실시간으로 공유할 수 있는 지속가능 정보관리 시스템의 필요성이 대두되고 있다. 본 연구는 건설업무의 생산성 향상을 위해 마감자재의 실시간 검색과 활용이 가능한 건축 마감자재정보 관리 시스템을 제시하고자 하는 것이다. 이를 위해서는 현행 자재정보 업무현황을 분석하고, 현장을 대상으로 설문조사를 실시하여 시스템 개발의 요구사항을 파악하고, 그 결과를 충분히 시스템에 반영시켜 실사용자가 쉽게 접근하고 활용할 수 있도록 하였다. 따라서 본 연구에서 제안하는 건설업무의 생산성 고도화를 위한 건축 마감자재 정보시스템은 시공품질 향상, 공사이익 극대화, 그리고 기업 경쟁력 강화에 활용될 수 있을 것으로 기대된다.

• Archives of Pharmacal Research
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• 제23권1호
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• pp.35-41
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• 2000

In order to investigate the stereochemical requirements of planar structure at 4-position of 4-phenyl-1-arylsulfonylimidazolidinones (1) for their cytoxicities against human cancer cell lines, the size, the distance from imidazolidinone ring, and the conformation of this moiety were variegated. Replacement of phenyl moiety with naphthyl in compounds 2 and 3 or benzyl moiety in compound 4 sharply reduced activity of 1. Conformational restriction on phenyl ring in compound 5 also resulted in the loss of activity of 1. Therefore, phenyl moiety without any substituents directly attached to imidazolidinone ring of 1 should be considered as an essential pharmacophore for this analog.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.329-334
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• 2001

Many of past studies using physically based numerical climate models indicate that increases in atmospheric $CO_2$could enhance summer dryness over continental region in middle-high latitudes. However the models used in those studies do not take account of permafrost in high latitudes. We have carried out a set of experiments applying a version of global climate model that can reproduce realistic distribution of the permafrost. From the results, it is indicated that permafrost functions as a large reservoir in hydrologic cycle maintaining dry, hot summer over continents in northern middle-high latitudes, and that the $CO_2$warming would reduce this function by causing climatological thawing of permafrost, which would result in moister and cooler summer, and warmer winter in the same region. The present study indicates that an inclusion of very simple description of soil freezing process can make a large difference in a model simulation.

• 한국분말재료학회지
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• 제29권2호
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• pp.166-175
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• 2022

Ppuri or Root technology primarily includes technologies such as casting, mold, plastic working, welding, heat treatment and surface treatment. It is regarded as an essential element for improving the competitiveness of the quality of final products. This study investigates the current status of smart factory implementation for Ppuri companies and analyzes the influencing relationships among various company factors. The factors affecting smart factory implementation for Ppuri companies are sales, exports, number of technical employees, and holding corporate research institutes. In addition, this research shows that even if smart factory implementation is pursued for data collection, data utilization is not implemented properly. Thus, it is suggested that the implementation of smart factories requires not only the availability of facilities and systems but also proper data utilization.

• Journal of Information Science Theory and Practice
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• 제10권spc호
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• pp.154-163
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• 2022

The purpose of this paper is to illuminate the role and importance of National Research & Education Network (NREN) in the national research and education field and to establish the future strategy of KREONET in Korea. To this end, we first carefully analyze the footsteps of NREN in major overseas countries, KREONET achievements, and future demand for KREONET. The history of NREN's development is divided into the 2000s, 2010s, and present by era, and classified into network infrastructure, network service, and next-generation network technology by subject. KREONET achievements are divided into advanced research support, network backbone and operation, and network service. Future demand analysis of users who use KREONET was conducted through Korea Research International Incorporation, a survey company. This paper presents the future development strategy of KREONET by analyzing KREONET achievements and future demand.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.432-438
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• 2011

The purpose of the present thesis is to develop bankruptcy prediction models capable of being applied to the Korean construction industry and to deduce an optimal model through comparative evaluation of final developed models. A study population was selected as general contractors in the Korean construction industry. In order to ease the sample securing and reliability of data, it was limited to general contractors receiving external audit from the government. The study samples are divided into a bankrupt company group and a non-bankrupt company group. The bankruptcy, insolvency, declaration of insolvency, workout and corporate reorganization were used as selection criteria of a bankrupt company. A company that is not included in the selection criteria of the bankrupt company group was selected as a non-bankrupt company. Accordingly, the study sample is composed of a total of 112 samples and is composed of 48 bankrupt companies and 64 non-bankrupt companies. A financial ratio was used as early predictors for development of an estimation model. A total of 90 financial ratios were used and were divided into growth, profitability, productivity and added value. The MDA (Multivariate Discriminant Analysis) model and BLRA (Binary Logistic Regression Analysis) model were used for development of bankruptcy prediction models. The MDA model is an analysis method often used in the past bankruptcy prediction literature, and the BLRA is an analysis method capable of avoiding equal variance assumption. The stepwise (MDA) and forward stepwise method (BLRA) were used for selection of predictor variables in case of model construction. Twenty two variables were finally used in MDA and BLRA models according to timing of bankruptcy. The ROC-Curve Analysis and Classification Analysis were used for analysis of prediction performance of estimation models. The correct classification rate of an individual bankruptcy prediction model is as follows: 1) one year ago before the event of bankruptcy (MDA: 83.04%, BLRA: 93.75%); 2) two years ago before the event of bankruptcy (MDA: 77.68%, BLRA: 78.57%); 3) 3 years ago before the event of bankruptcy (MDA: 84.82%, BLRA: 91.96%). The AUC (Area Under Curve) of an individual bankruptcy prediction model is as follows. : 1) one year ago before the event of bankruptcy (MDA: 0.933, BLRA: 0.978); 2) two years ago before the event of bankruptcy (MDA: 0.852, BLRA: 0.875); 3) 3 years ago before the event of bankruptcy (MDA: 0.938, BLRA: 0.975). As a result of the present research, accuracy of the BLRA model is higher than the MDA model and its prediction performance is improved.