• Journal of Internet Computing and Services
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• v.19 no.6
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• pp.133-145
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• 2018

Medical systems incurred accidents may result in significant damage for human being. Therefore, performing hazard analysis is important for medical system which is to identify hazard for preventing the accidents and minimizing the potential harm. Hazard analysis that is applied medical systems are difficult to apposite selected, because difference of analysis methods and applied development lifecycle is caused by objective of hazard analysis. It is required to select appropriate hazard analysis at concept phase during development lifecycle, owing to basic requirement elicitation to mitigate or prevent hazard based on identified hazard at concept phase. In this paper, hazard analysis methods, PHA and STPA, are compared at concept phase in which both methods have been applied on the medical system. As a result of compared methods, hazard analyst can be selected optimized hazard analysis methods for concept phase of the medical systems.

• Journal of the Korea Society of Computer and Information
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• v.12 no.4
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• pp.179-189
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• 2007

Every purchase a customer makes builds patterns about how products are purchased together. The process of finding these patterns, called market basket analysis, is composed of two steps in the Microsoft Association Algorithm. The first step is to find frequent item-sets. The second step which requires much less time than the first step does is to generate association rules based on frequent item-sets. Even though the first step, finding frequent item-sets, is the core part of market basket analysis, when applied to Online Analytical Processing(OLAP) cubes it always raises several points such as longitudinal analysis becomes impossible and many unpractical transactions are built up. In this paper, a new OLAP cube structures designing method which makes longitudinal analysis be possible and also makes only real customers' purchase patterns be identified is proposed for market basket analysis.

• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.113-119
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• 2014

Recently, the demand on the practical application of life-cycle cost effectiveness for design and rehabilitation of structure is rapidly growing unprecedently in engineering practice. Accordingly, in the 21st century, it is almost obvious that life-cycle cost together with value engineering will become a new paradigm for all engineering decision problems in practice. However, in spite of impressive progress in the researches on the LCC, the most researches have only focused on the Deterministic or Probabilistic LCC analysis approach (Level-1 LCC Model) at design stage. Thus, the goal of this study is to develop a practical and realistic methodology for the Lifetime risk based Life-Cycle Cost (LCC)-effective optimum decision-making at design stage.

• Korean Journal of Construction Engineering and Management
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• v.10 no.3
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• pp.32-41
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• 2009

In the execution of construction management, such pre-design steps as a planning stage, a basic design stage, and a work design stage are regarded as more important than an actual construction stage. However, the manpower input criterion from the aspect of construction management price standard in the Construction Engineering Management Law does not attach weight to the pre-design stage. In this regard, the aim of this study was to examine the propriety of manpower input in the pre-design stage of construction management and then present an improvement strategy of it. For this, the investigator examined the criterion of service price prescribed in the Construction Engineering Management Law and then comparatively analyzed four sites of construction management services. Study findings are as follows: 1) the actual state of manpower input based on the stepwise average price criterion of construction management service is presented with such steps as the newly established planning step (6.6%), the basic design stage (3.9%$\rightarrow$5.6%), the practical design stage(7.6%$\rightarrow$13.5%), the construction stage (88.5%$\rightarrow$64.0%), and the newly established maintenance stage (10.3%). The average price criterion is classified by total construction expenses and calculated by improved rates and stage; and 2) the three-step criterion of the Construction Engineering Management Law is classified into five stages including the planning stage and the maintenance stage by dividing it with the stepwise construction businesses. Study findings show that the calculation of price criterion in the actual site of construction management services must be operated in a practical and flexible manner and the systematic improvement of stepwise manpower input must be carried out actually.

• Communications for Statistical Applications and Methods
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• v.17 no.1
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• pp.67-77
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• 2010

In multinomial scheme with step-wise sampling, maximum likelihood estimates of multinomial probabilities are improved when some frequencies are merged. In this study, for cell probabilities in a I by J independent contingency tables, exact MLE and step-wise estimation methods are applied and the results are compared using MSE and Bias.

• Proceedings of the KOR-KST Conference
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• 1998.10a
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• pp.479-487
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• 1998

현재 도로화물운송을 분석하는데 가장 많이 사용되는 지표는 수송톤(ton)과 톤-키로(ton-km)이다. 하지만 이러한 두 지표는 도로화물운송체계를 설명하기보다는 단순히 운송실적을 나타내는 통계지표이다. 따라서 본 연구에서는 한국의 도로화물운송체계를 설명할 수 있는 운송단계, 총 운송거리, 순물동량, 평균운송거리 등의 4개 요소를 추정하였다. 그리고 한국의 도로화물 운송체계의 문제점을 진단하기 위하여 외국이 도로화물운송체계와 비교분석하였다. 본 연구에서 발견된 주요결과는 (1) 한국과 대만은 운송단계와 총 운송거리가 증가하고 평균운송거리는 감소하는 추세를 보였고, (2) 한국과는 대조적으로, 미국, 일본, 네덜란드는 운송단계와 총 운송거리는 감소하고 평균운송거리는 증가하는 변화추세를 보였으며, (3) 시계열 분석결과, 운송단계의 증가는 GDP대비 물류비와 운송비를 증가시키고 운송단계의 감소는 GDP대비 물류비와 운송비를 감소시키는 것으로 나타났다. 본 연구결과, 한국의 도로화물운송체계는 운송단계를 증가시키는 비효율적인 방향으로 진행되어왔고 이러한 운송단계의 증가는 GDP대비 물류비를 증가시키는 주요 원인임을 알 수 있었다. 따라서 한국의 도로화물운송체계를 개선시키기 위해서는 지능형 화물운송체계의 구축, 복합기능의 화물거점시설 확충, 화물자동차 운송업의 규제완화, 기업물류관리의 선진화 등의 정책을 통하여 불필요한 운송단계의 단축이 필요하다.

• Journal of the Korea Society for Simulation
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• v.2 no.1
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• pp.23-30
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• 1993

본 연구에서는 시뮬레이션을 통한 지식의 자동 획득(Simulation-Based Automatic Knowledge Acquistion) 가능성을 제시한다. 이을 위한 작업 단계는 다음과 같다. 첫째, 지식 제공자에 의한 대상(domain) 관련 초기 인과 관계 정보 입력 단계, 둘째 경험 베이스 탐색에 의한 확장된 정보 생성 단계, 세 번째로 생성되어진 정보를 사용하여 대상 반영 모델을 구축하는 단계, 네 번째로 구축된 모델을 시뮬레이션하고 수행 결과의 분석을 통해 새로운 지식을 획득하는 단계로 구성된다. 제안된 지식 획득 방법은 ,대상에 관계된 개념과 개념들의 인과 관계를 바탕으로 모델을 자동 생성하여 이를 지식 획득 표현틀로 이용하는 유연한 구조를 사용하였고, 또한 생성된 모델의 시뮬레이션 결과를 분석함에 의해 새로운 지식을 획득함으로써 획득된 지식이 동적 세계를 잘 반영할 있도록 하였다.

• Korean Journal of Construction Engineering and Management
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• v.11 no.5
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• pp.15-23
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• 2010

Construction management(CM) in the private building sector has been leading the growth of the CM market in Korea. The use of CM services during pre-construction stages has been recognized as a critical factor to succeed in construction projects. Understanding clients' needs of pre-construction CM services is important for CM fedms to strategically prepare and cope with market needs. The objective of this paper is to investigate the level of use of CM services in private building projects during pre-construction stages, and to identify key characteristics and implications. The most distinctive characteristics include the high demand and use of cost management and time management services during pre-construction stages.

• Journal of Korea Port Economic Association
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• v.28 no.1
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• pp.53-82
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• 2012

The purpose of this paper is to show the clustering trend by using the context-dependent and measure-specific models for 38 Asian ports during 10 years(2001-2009) with 4 inputs and 1 output. The main empirical results of this paper are as follows. First, clustering results by using context-dependent and measure-specific models are same. Second, the most efficient clustering was shown among the Hong Kong, Singapore, Ningbo, Guangzhou, and Kaosiung ports. Third, Port Sultan Qaboos, Jeddah, and Aden ports showed the lowest level clustering. Fourth, ranking order of attractiveness is Guangzhou, Dubai, HongKong, Ningbo, and Shanghai, and the results of progressive scores confirmed that low level ports can increase their efficiency by benchmarking the upper level ports. Fifth, benchmark share showed that Dubai(birth length), and HongKong(port depth, total area, and no. of cranes) have affected the efficiency of the inefficient ports.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.185-187
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• 2004

소프트웨어를 개발할 때 작성되는 명세서들은 개별특성으로 인해 연속적인 자동화가 이루어지지 않으며, 소프트웨어 감리에서도 많은 불일치 항목이 발견된다. 본 논문에서는 분석 및 설계단계에서 작성되는 명세서간 불일치를 검출하기 위해 시스템 개발과정에 대해 실시한 감리결과 보고서를 분석하여 불일치가 발생하는 연관된 명세서를 내용별로 분류하고, 이를 바탕으로 분석, 설계, 테스트 단계별로 사용되는 명세서간 불일치 추출방안을 제안한다. 이를 이용하면, 분석 및 설계단계에서 작성되는 명세서의 오류를 줄임으로써 최종산출물인 소프트웨어에 대한 품질을 향상시킬 수 있다.