• 제목/요약/키워드: Alternative Model

검색결과 3,008건 처리시간 0.032초

Planning of alternative countermeasures for a station blackout at a boiling water reactor using multilevel flow modeling

  • Song, Mengchu;Gofuku, Akio
    • Nuclear Engineering and Technology
    • /
    • 제50권4호
    • /
    • pp.542-552
    • /
    • 2018
  • Operators face challenges to plan alternative countermeasures when no procedure exists to address the current plant state. A model-based approach is desired to aid operators in acquiring plant resources and deriving response plans. Multilevel flow modeling (MFM) is a functional modeling methodology that can represent intentional knowledge about systems, which is essential in response planning. This article investigates the capabilities of MFM to plan alternatives. It is concluded that MFM has a knowledge capability to represent alternative means that are designed for given ends and a reasoning capability to identify alternative functions that can causally influence the goal achievement. The second capability can be applied to find originally unassociated means to achieve a goal. This is vital in a situation where all designed means have failed. A technique of procedure synthesis can be used to express identified alternatives as a series of operations. A case of station blackout occurring at the boiling water reactor is described. An MFM model of a boiling water reactor is built according to the analysis of goals and functions. The accident situations are defined by the model, and several alternative countermeasures in terms of operating procedures are generated to achieve the goal of core cooling.

DLT 기반의 대안적 모형화(Alternative Sensor Model) 방법을 이용한 SPOT 위성영상의 DEM 생성에 관한 연구 (A Study for the DEM Generation from the SPOT Imagery Using Alternative Sensor Model Based on DLT)

  • 양인태;이인엽;오명진
    • 대한공간정보학회지
    • /
    • 제12권2호
    • /
    • pp.67-71
    • /
    • 2004
  • 위성영상의 종류가 증가하고 취득이 용이해 짐에 따라 위성영상을 이용한 수치고도모형의 생성에 관한 연구가 활발히 진행되어 왔다. SPOT의 경우 $60km{\times}60km$에 해당하는 광범위한 지역에 대한 영상을 취득할 수 있어 넓은 지역에 대한 수치고도모형을 생성 할 수 있는 이점이 있다. 기존의 엄밀센서모형(Rigorous Sensor Model)의 경우 위성의 천문력자료(Ephemeris Data)와 지상기준점을 사용하여 복잡한 과정을 거쳐 DEM을 생성하였으나 본 연구에서는 직접선형변환(DLT)에 기반을 둔 대안적 모형화 기법을 이용하여 DEM을 생성해 보았다. 결과적으로 직접선형 변환의 경우 소수의 기준점을 통하여 양호한 품질의 DEM을 취득할 수 있음을 확인 할 수 있었다.

  • PDF

Exploration and Development of SERVQUAL

  • Kim, Yong-Pil;Kim, Kye-Wan;Yun, Deok-Gyun
    • International Journal of Quality Innovation
    • /
    • 제4권1호
    • /
    • pp.116-130
    • /
    • 2003
  • The gap-based SERVQUAL model is a popular service quality determinant due to its superior diagnostic capacity over alternative explanatory frameworks. However, some researchers criticize the performance of the SERVQUAL model and propose alternative service Quality measurement constructs. Nevertheless, it is argued that the superior diagnostic capacity of SERVQUAL is its key strength; and that any criticism made of it when making comparison with alternative models does not reflect the differing nature of scales of statistical analysis. Arguably, the only limitation of a gap-based model is misinterpretation of customers' evaluation and perception of a service. In this research, the gap score is transformed into a ratio score. Also, empirical tests and implications are presented to support this alternative contribution to the body of knowledge.

항만 민영화 대안 선정을 위한 모형개발 (Development of Model for the Alternative Selection of Port Privatization)

  • 백인흠
    • 수산해양교육연구
    • /
    • 제26권6호
    • /
    • pp.1442-1450
    • /
    • 2014
  • The aim of this study is to develop a model for the alternative selection in port privatization using Brainstorming, the ISM and AHP methods. For this, 30 detailed attributing factors were identified by both previous studies and port users, Also, 13 attributing evaluation factors were identified by a group of port experts using the brainstorming method. These were made into a model of hierarchical structure with 3 levels, taking 1 goal factor, 5 evaluation factors and 7 alternative factors using the ISM method. The collected date of questionnaires through the AHP method were analyzed with a group of port experts for an empirical analysis. The result of the hierarchical level 2 shows that profitability is the most important factor, followed by public interest, management professionality, service quality and financial soundness. The analysis results of hierarchical level 3 shows that commercialization is the most important factor.

COMPARISON OF VARIABLE SELECTION AND STRUCTURAL SPECIFICATION BETWEEN REGRESSION AND NEURAL NETWORK MODELS FOR HOUSEHOLD VEHICULAR TRIP FORECASTING

  • Yi, Jun-Sub
    • Journal of applied mathematics & informatics
    • /
    • 제6권2호
    • /
    • pp.599-609
    • /
    • 1999
  • Neural networks are explored as an alternative to a regres-sion model for prediction of the number of daily household vehicular trips. This study focuses on contrasting a neural network model with a regression model in term of variable selection as well as the appli-cation of these models for prediction of extreme observations, The differences in the models regarding data transformation variable selec-tion and multicollinearity are considered. The results indicate that the neural network model is a viable alternative to the regression model for addressing both messy data problems and limitation in variable structure specification.

자동차 공기현가 공압회로 해석 및 대체회로 설계 (Analysis and Alternative Circuit Design of Pneumatic Circuit for An Automotive Air Suspension)

  • 이재천
    • 유공압시스템학회논문집
    • /
    • 제5권4호
    • /
    • pp.17-25
    • /
    • 2008
  • This study presents an analytical model of the pneumatic circuit of an air suspension system to analyze the characteristics of vehicle height control. The analytical model was developed through the co-simulation of Simulink(air spring) and HyPneu(pneumatic circuit). Variant effective area of air spring and flow coefficients of pneumatic valves were estimated experimentally prior to the system test, and utilized in simulation. One-comer test apparatus was established using the components of commercial air suspension products. The results of simulation and experiment were so close that the proposed analytical model in this study was validated. However the frictional loss of conduit and heat dissipation which were ignored in this study need to be considered in future study. As an application example of proposed analytical model, an alternative pneumatic circuit of air suspension to conventional WABCO circuit was evaluated. The comparison of simulation results of WABCO circuit and alternative circuit show that proposed analytical model of co-simulation in this study is useful for the study of pneumatic system of automotive air suspension.

  • PDF

시스템 원형을 활용한 시스템 다이내믹스 모형 구축: 대체연료차량 시장 모형의 예 (Building a Market Share Model of Alternative Fuel Vehicles: From Generic System Archetypes to System Dynamics Modeling)

  • 권태형
    • 한국시스템다이내믹스연구
    • /
    • 제9권2호
    • /
    • pp.27-43
    • /
    • 2008
  • This study investigates market barriers in increasing the market share of Alternative Fuel Vehicles (AFVs). In particular, this study first conceptualizes the AFVs market model with the aid of generic system archetypes suggested by Wolstenholme. Among four generic system archetypes suggested by Wolstenholme, the market structure of AFVs can be explained by the 'relative achievement' archetype. Starting from the generic system archetype, this study extends the model boundary step by step to take account of various model assumptions necessary to simulate the model numerically. If there is a significant network effect on vehicle operating costs, it is difficult to achieve the shift to AFVs even in the long term without a policy intervention because the car market is locked into the current structure. There are several possible policy options to break the 'locked-in' structure of the car market, such as subsidies on vehicles, subsidies on fuels, and a niche management policy.

  • PDF

이산사건 시뮬레이션과 BIM을 활용한 설계대안 평가에 관한 연구 (Design Alternative Assessment Method using Discrete Event Simulation and Building Information Model)

  • 이창용;이동은
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
    • /
    • pp.158-159
    • /
    • 2016
  • Construction project consists of several stages such as planning, design, construction, operation/maintain, etc. Decisions made in the planning and design stage have a significant impact on the construction and operation/maintain stages. Identifying key resources contributing to duration and cost of design alternatives is an important measure to achieve effective coordination between design and construction. This study proposes a method which finds an optimal design alternative by taking into account of resource planning, expected duration, and cost in construction stage. Base on literature review relative to the assessment of design alternatives, a method which predicts required resources, duration, and cost of the design alternative is established. Then, a method that identifies an optimal design alternative based on the preference of a certain project criteria is developed. Finally, a case study is presented.

  • PDF

아토피 피부염 유사 NC/Nga 마우스 모델에서 유용 미생물 발효물질의 항염증효과 (Anti-inflammatory Effects of Effective Microorganism Fermentation Substance on Atopic Dermatitis-like NC/Nga Mouse Model)

  • 목지예;정승일;조정근;최지원;남상윤;장원길;문병은;박광현;장선일
    • 동의생리병리학회지
    • /
    • 제24권2호
    • /
    • pp.258-265
    • /
    • 2010
  • Atopic dermatitis (AD) is a chronically relapsing pruritic inflammatory skin disease. To find new anti-inflammatory products for skin inflammatory disease such as AD and contact dermatitis, we produced the effective microorganism fermentation substance (EM-S) by fermentation of medicinal plants with effective microorganisms including photosynthetic bacteria, lactic acid bacteria and yeast, screened the effects of EM-S on NC/Nga model mice. Murine AD-like skin lesions were made by painting Dermatophagoides farinae (Df) extract. Topically applied EM-S significantly reduced clinical severity score, ear thickness and histological grade in AD-like NC/Nga mouse model by Df antigen sensitization. In addition, the serum IgE and Th2 chemokine levels (TARC/CCL17, MDC/CCL22 and CTACK/CCL27) were significantly reduced by EM-S. Futhermore, skin tissue expressions of Th2 chemokines were significantly reduced by EM-S. These results demonstrate that topical application of EM-S may be improve the AD-like skin lesion by suppressing IgE and Th2 chemokines.

여성의 SNS 이용이 대안 건강 행동에 미치는 영향: 건강신념모델에 기초한 대안 생리대 사용 의도를 중심으로 (Effects of Women's SNS Uses on Alternative Health Management Behaviors: Application of Health Belief Model on the Adoption of Alternative Menstrual Products)

  • 김총혜;조재희
    • 인터넷정보학회논문지
    • /
    • 제19권4호
    • /
    • pp.83-93
    • /
    • 2018
  • 본 연구는 여성들의 SNS 이용이 대안 건강행동에 미치는 영향에 대해 분석해 보고자 했다. 특히 최근 많은 주목을 받았던 독성생리대와 대안생리대에 대한 SNS 정보추구가 대안생리대에 대한 이용의도에 미치는 영향에 주목했다. 이를 위해, 건강신념모델을 기반으로 가설을 설정했고, 총 11개의 가설을 온라인 설문을 통해 수집된 자료에 대한 경로분석을 통해 분석했다. 경로분석 결과를 살펴보면, SNS를 통해 수집된 독성생리대와 대안생리대에 대한 정보이용은 대안생리대에 대한 지각된 이익과 독성생리대에 대한 지각된 민감성에 유의미한 영향을 미치는 것으로 나타났다. 또한 자기효능감, 지각된 민감성, 지각된 이익, 그리고 지각된 장애는 대안생리대의 사용의도에 유의미한 영향을 미치는 것으로 나타났다.