• 제목/요약/키워드: Survey Method

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최대 엔트로피 분포를 이용한 퍼지 관측데이터의 분석법에 관한 연구 (An Analysis of Fuzzy Survey Data Based on the Maximum Entropy Principle)

  • 유재휘;유동일
    • 한국컴퓨터정보학회논문지
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    • 제3권2호
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    • pp.131-138
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    • 1998
  • 통상 통계적인 데이터 해석에서 취급되는 데이터는 확정된 값으로서 통계 처리를실시한다. 그러나 복잡˙대규모화하는 현대의 시스템에 있어서는 정확하게 측정된 데이터만을 취급하는 것은 곤란하며 인간의 주관적인 판단에 따른 데이터를 수집하는 경우가 발생하게 된다. 본 연구에서는 이러한 인간의 주관적인 판단에 따른 데이터를 퍼지 관측 데이터로하여(언어 변수에 의해 Membership 함수를 정의한다.) 최대 엔트로피 원리를 이용한 새로운 분석 방법을 제안한다. 또한 보다 현실적인 상황 아래 시뮬레이션을 실시함으로서 제안모델의 유효성을 검증한다.

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전자통신설비의 SPD 소손사례 및 열화진단기법 분석 (Survey of Damage Cases for Surge Protective Devices Installed Electrical Communication Systems and Analysis of Degradation Diagnosis Method)

  • 임종욱;이재영;권준혁
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2009년도 정보통신설비 학술대회
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    • pp.15-18
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    • 2009
  • In recent years electric devices and telecommunication facilities were often damaged by surge generated lightning discharge. When the service was interrupted by failure of electrical devices due to surge the social loss is very enormous. Therefore in order to protect electrical systems against lightning, SPDs(Surge protective device) have been used But damaged SPDs often make some troubles like fire and interrupt of service. In this work, 3rd harmonic leakage current defection method was applied as the diagnosis of SPD degradation and the effectiveness of this method was verified by field survey.

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연료전지 하이브리드 자동차의 에너지 운용전략에 관한 기술조사 (Survey on Energy Management Strategy for Fuel Cell Hybrid Electric Vehicles)

  • 이남수;정구민;안현식;김도현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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    • pp.511-513
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    • 2005
  • The fuel cell system has inherent limitation such as slow response time and low fuel economy especially at the low power region, and thus, the battery system has come to be used to compensate for the fuel cell system. This type of hybrid configuration has many advantages, however, the energy management strategy is essentially required. The work in this paper presents survey on recent power management strategies for fuel cell hybrid electric vehicles. For three power management strategies: basic control method. object function-based control method, and fuzzy logic-based control method. each strategy is reviewed and discussed with other strategy.

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작업평가방법론 및 현장 적용 고찰 (A Survey on the Workload Evaluation Methods and Their Applications to WMSD Work in Industries)

  • 박재희
    • 대한인간공학회지
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    • 제29권4호
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    • pp.435-444
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    • 2010
  • To identify and evaluate the risk factors in WMSD work, a number of ergonomic workload evaluation methods have been developed. In the legal examination of WMSD risk factors, simple observational workload evaluation methods are widely used instead of using costly measurement equipments such as EMG and motion analyzer. The simple workload evaluation methods can be categorized into three groups; risk factor checklist methods, posture observation methods, and manual material handling task evaluation methods. In terms of the categories, this survey summarized several representative workload evaluation methods and compared them each other. Then some industrial application cases referring each the workload evaluation methods were surveyed. Due to the characteristics of each method, the selection and application procedure of workload evaluation method should be appropriate for the corresponding work. Therefore, some guidelines for the selection and application procedure of workload evaluation method were suggested.

수직 탄성파탐사를 응용한 터널 전방의 불연속면 예측과 암반 물성 파악 (Prediction of Discontinuity and Determination of Rock Property ahead of Tunnel Face by VSP application)

  • 남기천;이진무;차성수
    • 터널과지하공간
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    • 제5권3호
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    • pp.214-222
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    • 1995
  • Geological events which are undetected by the surface geophysical or geological survey phase can cause many problems, especially when the tunnel is excavated by TBM. To detect the geological events ahead of tunnel face, a seismic method applied from VSP method is used. Generally uniaxial geophone has been used in surface seismic survey. But this time, triaxial geophone is used to reduce the noise of tunnel wave. DME(Dip moveout Enhancement) filter and diffraction stack method are used. Applying these techniques to the road tunnel in construction, it is proved that the geological events ahead of tunnel face is fairly well predicted. From the seismic trace, Vp and Vs which are related to the rock property can be also obtained. Rock property and proper support design can be dedced from these parameters.

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층화이중추출을 이용한 결합 확률화응답기법 (A Combined Randomized Response Technique Using Stratified Two-Phase Sampling)

  • 홍기학
    • 응용통계연구
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    • 제17권2호
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    • pp.303-310
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    • 2004
  • 본 연구에서는 민감한 모집단에 대한 자료수집 방법으로 직접 질문 방법 인 Black-Box 방법과 간접 질문 방법인 확률화응답기법(RRT)의 결합적 방법을 제시하였고, 층화이중추출방법을 이용하여 모수를 추정하였다. 또한, 주어진 추정량의 효율성을 Mangat과 Singh 추정량과 비교 분석하였다.

생활과학에서의 여가연구에 대한 분석적 고찰 (Leisure Study in Human Ecology : An Analytic Review)

  • 김유경;기은광;이기영
    • 가족자원경영과 정책
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    • 제6권1호
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    • pp.17-33
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    • 2002
  • The purpose of this study is to analyze leisure studies in human ecology of Korea and to discuss them. For this analysis, the articles which were published on the Journal of Korean Home Economics Association, the Journal of Korean Home Management Association, and the Journal of Korean Family Resource Management Association were investigated by theme, research subject, and research method. Leisure studies in human ecology began with the survey of time-use or activity patterns and they were focused on the housewives. Since the latter half of the 1990' s varied groups -especially the old- are subject to sample, and the shared leisure is studied, varied themes are studied. The research method were deflected to the survey using questionnaire all throughout the period. For the future study, we suggest that the general theories developed and the appropriate research method applied.

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Variance Estimation for Imputed Survey Data using Balanced Repeated Replication Method

  • Lee, Jun-Suk;Hong, Tae-Kyong;Namkung, Pyong
    • Communications for Statistical Applications and Methods
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    • 제12권2호
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    • pp.365-379
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    • 2005
  • Balanced Repeated Replication(BRR) is widely used to estimate the variance of linear or nonlinear estimators from complex sampling surveys. Most of survey data sets include imputed missing values and treat the imputed values as observed data. But applying the standard BRR variance estimation formula for imputed data does not produce valid variance estimators. Shao, Chen and Chen(1998) proposed an adjusted BRR method by adjusting the imputed data to produce more accurate variance estimators. In this paper, another adjusted BRR method is proposed with examples of real data.

An Implementation of Web-based Unified Randomized Response System for Obtaining Sensitive Information and Application Method

  • Lee, Gi-Sung;Nam, Ki-Seong;Son, Chang-Kyoon
    • Journal of the Korean Data and Information Science Society
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    • 제17권4호
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    • pp.1237-1250
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    • 2006
  • In this paper we develop the web-based unified randomized response system for obtaining more reliable response to the sensitive characteristic such as a crime of violence at home, and a bribing and so on. This survey system embody to apply with from the classical to recently research, for example from the Warner's model to the 2-stage model. In addition, our survey system is able to link between the typical and the randomized response system. Finally, our survey system looks into a variation according to various sensitive questions as well as it can be used for a single question.

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An Empirical Approach to Evaluate Management Performance Using a Trading Area Analysis: Focus on Small and Medium-sized Retail Businesses

  • Bae, Jae-Ho
    • 유통과학연구
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    • 제10권12호
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    • pp.5-11
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    • 2012
  • Purpose - This paper proposes measurement models to evaluate the management performance of small and medium-sized retail businesses on the basis of a trading area analysis that compares their proposed revenue to actual revenue in the trading area. Research design, data, methodology - The study proposes measurement models consisting of five stages, namely: (1) district background survey, (2) customer survey, (3) competitor survey, (4) business district survey, and (5) business performance analysis. Results - To identify business districts easily, this study preferred a minor-adjusted method based on the Euclidean distance, as it is simple to employ for the small and medium-sized businesses. This model was applied to select coffee shops in Daejeon. Results indicated that although the targeted shop was not located in an appropriate location, actual sales were higher than expected. Conclusions - Small- or medium-sized retail businesses face difficulties regarding the economies of scale and brand recognition and must choose an appropriate location to ensure management stability. However, such businesses will find it difficult to evaluate their competitive edge accurately using a trading area analysis.

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