• 제목/요약/키워드: Reliability analyses

검색결과 1,047건 처리시간 0.036초

인터넷 쇼핑몰의 특성과 사용자 수용간의 상황적 관계분석 (A Contingent Analyses on the Relationship Between the Characteristics of Internet Shopping Mall and User Acceptance)

  • 서건수
    • Asia pacific journal of information systems
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    • 제11권2호
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    • pp.23-55
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    • 2001
  • It is generally agreed that realizing the full potential of the internet shopping mall(ISM) requires careful identification of customer needs and expectations. However, a quantitative framework to explain and predict users' behavior toward ISM has not been well established because the research on the user acceptance of ISM is still in its infancy. This study proposes a model which uses factor analysis to identify factors of ISM characteristics and individual characteristics affecting user acceptance of ISM. Predictive models based on the multiple regression analyses select the factors and their interactions with individual characteristics that significantly influence user acceptance. Results show that five factors including economy, convenience, credibility, reliability, information risks, and performance risks affects user acceptance. In addition, individual differences in terms of innovativeness, playfulness, and recreational shopping traits have both direct and interaction effects on user acceptance. The implication of this study is that, although user attitudes towards ISM characteristics in general are important to their acceptance behavior, the level of importance depends upon different user groups.

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공사비 예측시 이상값 존재하에서 데이터 처리 분석 방안 (Methodology of data analyses under presence of outliers for estimating construction cost)

  • 오세대;허영기
    • KIEAE Journal
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    • 제7권3호
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    • pp.31-37
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    • 2007
  • Statistical analyses with actual data are used in estimating construction cost for many years, but collected data could include factors that distort analytical results, namely outliers. To enhance reliability in predicting construction cost, the methodology, which is able to identify outliers and determine how to manage them, is needed. Actual costs obtained from 22 construction projects were studied. It is found that there is substantial disparity between results considering outliers and results not considering ones. Therefore, it is to identify outliers and apply an optimum process in estimating construction cost when actual data is used in statistical analysis.

Safety Analyses of Process and Facility for the ACP Demonstration

  • You, Gil-Sung;Choung, Won-Myung;Ku, Jeong-Hoe;Cho, Il-Je;Kook, Dong-Hak;Lee, Eun-Pyo;Park, Seong-Won
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 2005년도 춘계학술발표회
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    • pp.293-294
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    • 2005
  • The safety analyses and evaluation works on the process and facility for ACP demonstration have been performed. The several safety factors, such as the risk, environmental, radiation, structural, criticality, were analyzed. The analysis results confirmed the reliability of the safety on the ACP process and facility during normal and accident conditions.

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RM 등기하 판요소를 이용한 적층판의 자유진동 및 선형좌굴 해석 (Vibration and Buckling Analysis of Laminated Composite Plates using RM Isogeometric General Plate Element)

  • 김하룡;이상진
    • 한국공간구조학회논문집
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    • 제14권2호
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    • pp.59-68
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    • 2014
  • A study on the vibration and buckling analyses of laminated composite plates is described in this paper. In order to carry out the analyses of laminated composite plates, a NURBS-based isogeometric general plate element based on Reissner-Mindlin (RM) theory is developed. The non-uniform rational B-spline (NURBS) is used to represent the geometry of plate and the unknown displacement field and therefore, all terms required in this element formulation are consistently derived by using NURBS basis function. Numerical examples are conducted to investigate the accuracy and reliability of the present plate element. From numerical results, the present plate element can produce the isogeometric solutions with sufficient accuracy. Finally, the present isogeometric solutions are provided as future reference solutions.

통계처리용 소프트웨어 패키지의 품질 비교에 관한 연구 (A Study on The Quality Comparison of Software Packages for Statistical Analyses)

  • 이상석;윤민석
    • 품질경영학회지
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    • 제27권1호
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    • pp.195-210
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    • 1999
  • The multiplicity of software packages brings about a choice problem to the end-user and a multi-fold intensity to the competing developer. This study intends to provide guidelines solving the problems for both the end-user and the developer of packages for automatic statistical analyses. For the purpose, we adopt an appropriate evaluation model in terms of user-perceived quality through the applicable criteria and an evaluation method. The result of empirical study is described, which shows that the weight of each criterion is dynamic along usage levels. Briefly, functionality, usability, and reliability are key factors to contribute to the perceived quality. The empirical study also illustrates a comparative analysis on the dominant products, SAS and SPSS, in Korea.

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시뮬레이션 기법을 이용한 지진 시 사면안정 해석 (Simulation-Based Assessment of Seismic Slope Stability)

  • 김진만
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 춘계 학술발표회논문집
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    • pp.157-164
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    • 2003
  • A simulation-based approach that can be used to systematically model the uncertainties of seismic loading and geotechnical property is presented in the context of reliability analysis of slope stability. The uncertainty of seismic loading is studied by generating a large series of hazard-compatible artificial motions, and by using them in subsequent response analyses. The stochastic nature of spatially varying material properties and also the uncertainty arising from insufficient information are treated in the framework of random fields. The simulation-based analyses indicate that in a seismically less active region, a moderate variability in soil properties has a relatively large effect as much as characterization of earthquake hazard on the computed risk of slope failure and excessive slope deformations.

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Evaluation of local and global ductility relationships for seismic assessment of regular masonry-infilled reinforced concrete frames using a coefficient-based method

  • Su, R.K.L.;Tang, T.O.;Lee, C.L.
    • Earthquakes and Structures
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    • 제5권1호
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    • pp.1-22
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    • 2013
  • Soft storey failure mechanism is a common collapse mode for masonry-infilled (MI) reinforced concrete (RC) buildings subjected to severe earthquakes. Simple analytical equations correlating global with local ductility demands are derived from pushover (PO) analyses for seismic assessments of regular MI RC frames, considering the critical interstorey drift ratio, number of storeys and lateral loading configurations. The reliability of the equations is investigated using incremental dynamic analyses for MI RC frames of up to 7 storeys. Using the analytical ductility relationship and a coefficient-based method (CBM), the response spectral accelerations and period shift factors of low-rise MI RC frames are computed. The results are verified through published shake table test results. In general applications, the analytical ductility relationships thus derived can be used to bypass the onerous PO analysis while accurately predicting the local ductility demands for seismic assessment of regular MI RC frames.

학습자 중심의 '강의평가' 도구 개발 및 타당화 연구 (A study for development and validation of the 'course evaluation' scale for learner-centered)

  • 박성미
    • 수산해양교육연구
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    • 제23권1호
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    • pp.13-22
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    • 2011
  • The purpose of this study was to development and validation of the 'course evaluation' scale for learner-centered in university. The research collected preliminary data from 1,567 university students's responses for item and scale quality analyses, and collected 2,539 university students's for item and scale quality analyses, and 300 university professors's responses for validation. Data were analyzed to obtain item quality, reliability, and validity analysis. The results of the study were as follows; The 'course evaluation' scale for learner-centered in university was defined by 5 factors. The 5 factors were structure and sincerity of lecture, suitability of report and test, level of consulting for student, application of educational media, communication. The results of the confirmatory factor analysis confirmed five sub-scales in the 'course evaluation' scale for learner-centered in university scale. Criterion-related validity evidence was obtained from the correlation analysis as the criterion measures. Cross validity evidence was obtained from the confirmatory factor analysis in university professors.

이산요소법을 이용한 Graphite 분말 압축 특성 연구 (A Study on Graphite Powder Compaction Behaviors Using the Discrete Element Method)

  • 정준혁;최진일
    • 한국분말재료학회지
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    • 제28권1호
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    • pp.1-6
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    • 2021
  • Accurate and effective powder compaction analyses are performed for brittle materials such as graphite, utilized as a solid lubricant, by using the discrete element method (DEM). The reliability of the DEM analysis is confirmed by comparing the results of graphite powder compaction analyses using the DEM particle bonding contact model and particle non-bonding contact model with those from the powder compaction experiment under the same conditions. To improve the characteristics, the parameters influencing the compaction properties of the metal-graphite mixtures are explored. The compressibility increases as the size distribution of the graphite powder increases, where the shape of the graphite particles is uniform. The improved compaction characteristics of the metal-graphite (bonding model) mixtures are further verified by the stress transmission and compressive force distribution between the top and bottom punches. It is confirmed that the application of graphite (bonding model) powders resulted in improved stress transmission and compressive force distribution of 24% and 85%, respectively.

Wave Analysis Method for Offshore Wind Power Design Suitable for Suitable for Ulsan Area

  • Woobeom Han;Kanghee Lee;Seungjae Lee
    • 신재생에너지
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    • 제20권2호
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    • pp.2-16
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    • 2024
  • Various loads induced by marine environmental conditions, such as waves, currents, and wind, are crucial for the operation and viability of offshore wind power (OWP) systems. In particular, waves have a significant impact on the stress and fatigue load of offshore structures, and highly reliable design parameters should be derived through extreme value analysis (EVA) techniques. In this study, extreme wave analyses were conducted with various Weibull distribution models to determine the reliable design parameters of an OWP system suitable for the Ulsan area. Forty-three years of long-term hindcast data generated by a numerical wave model were adopted as the analyses data, and the least-squares method was used to estimate the parameters of the distribution function for EVA. The inverse first-order reliability method was employed as the EVA technique. The obtained results were compared among themselves under the assumption that the marginal probability distributions were 2p, 3p, and exponentiated Weibull distributions.