• 제목/요약/키워드: conceptual components

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액체로켓엔진 가스발생기 사이클의 배관망 해석 (Pipe Network Analysis for Liquid Rocket Engine with Gas-generator Cycle)

  • 임태규;이상복;노태성
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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    • pp.52-57
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    • 2012
  • 액체로켓은 연소기, 가스발생기, 터보펌프, 터빈 등으로 구성된 시스템이며, 각 요소들을 연결해주는 공급계 부품들로 구성되어 있다. 각 부품들이 액체로켓 성능에 복합적인 영향을 미치기 때문에 개념설계 전 시스템의 전체적인 예비해석이 반드시 필요하다. 액체로켓 엔진 시스템의 각 구성품 모듈을 고려한 통합 해석 프로그램의 개발은 이루어지지 않았다. 본 논문에서는 액체로켓 공급계 부품의 모델구성 및 검증을 거친 후 가스발생기 사이클 구성하였으며, 대표적인 가스발생기 사이클인 F-1 엔진의 결과와 비교하였다.

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A Framework of Medical Tourism as a Niche Trade Item: A System Approach

  • Kho, Tae-Gyou
    • Journal of Korea Trade
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    • 제25권2호
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    • pp.1-21
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    • 2021
  • Purpose - The purpose of this research is to develop two medical tourism system models which explain medical tourism phenomenon with a systemic approach. Design/methodology - This research was conducted by using a qualitative data analysis which mainly refers to previous references of medical tourism in the areas of tourism and medicine. Leiper's tourism system model was utilized as a conceptual framework. In-depth interviews with experts in the field were conducted in order to pretest the models. Findings - This research suggests a medical tourism system framework and a medical service provision framework. The first model presents medical tourism components and their relationships within a framework presented in a diagram. The second model shows the relationships among medical services required by medical tourists, the service providers, and service human resources along with movements of medical tourists. Originality/value - The first model presents a spatial composition of medical tourism components and their relationships, whereas the second model shows the linkage among medical services, the service providers, and relevant service human resources along with time sequential steps of medical tourists. These two models are complementary and may be used as useful tools to observe medical tourism phenomenon with a systemic and holistic approach. These two models may enable stake holders avoid unnecessary confusions and conflicts that result in duplication of government policies and a waste of budget and human resources.

MIT PEBBLE BED REACTOR PROJECT

  • Kadak, Andrew C.
    • Nuclear Engineering and Technology
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    • 제39권2호
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    • pp.95-102
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    • 2007
  • The conceptual design of the MIT modular pebble bed reactor is described. This reactor plant is a 250 Mwth, 120 Mwe indirect cycle plant that is designed to be deployed in the near term using demonstrated helium system components. The primary system is a conventional pebble bed reactor with a dynamic central column with an outlet temperature of 900 C providing helium to an intermediate helium to helium heat exchanger (IHX). The outlet of the IHX is input to a three shaft horizontal Brayton Cycle power conversion system. The design constraint used in sizing the plant is based on a factory modularity principle which allows the plant to be assembled 'Lego' style instead of constructed piece by piece. This principle employs space frames which contain the power conversion system that permits the Lego-like modules to be shipped by truck or train to sites. This paper also describes the research that has been conducted at MIT since 1998 on fuel modeling, silver leakage from coated fuel particles, dynamic simulation, MCNP reactor physics modeling and air ingress analysis.

Sense of Coherence in Salutogenic Paradigm

  • Chung, Chae-Weon
    • 대한간호학회지
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    • 제29권5호
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    • pp.1049-1057
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    • 1999
  • The central concept of the Salutogenic Model is sense of coherence, which is defined as a global orientation that expresses the extent to which one has a feeling of confidence that one's internal and external environments are comprehensible, manageable, and meaningful. Sense of coherence is proposed as a determinant of positive health consequences and successful coping. The purpose of this article is to review Antonovsky's Salutogenic Model, the concept of sense of coherence, and its central components and sources. For conceptual clarity, sense of coherence is compared and contrasted with the concept of hardiness. The empirical research findings are integrated to better understand sense of coherence and to enhance future implications for nursing research and practice.

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학습모형을 이용한 워드프로세서의 평가방법 개발 (The evaluation of Word Processors by Learning Model)

  • 손일문;홍상우;이상철
    • 산업경영시스템학회지
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    • 제20권41호
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    • pp.203-212
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    • 1997
  • The interface of computer software has to promote human-computer interaction. The one quality of interface to promote HCI should be evaluted with regard to user's information processing. The usability of interface is one of the main components of it's quality, and it is straightforwardly concerned with learnability, especially when users want to use a software at the first stage. In this paper, word processors, wide spreadly used in OA environments is studied in respect to menu structure on the interface. An cognitive menu structure is suggested by user's conceptual network of the main functions of word processor. Two word processors is selected to compare with the cognitive menu structure and to evalute learnabilities by teaming model.

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Conceptual Study of Fusion-Fission Hybrid Reactor for Transmutation of a Nuclear Waste

  • Hong, B.G.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.670-670
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    • 2013
  • The concept of a fusion-driven transmutation reactor based on LAR (Low Aspect Ratio) tokamak as a neutron source is studied based on ITER physics and technology. The radial build of transmutation reactor components are self-consistently determined by coupling the systems analysis with radiation transport analysis and an optimal configuration of a transmutation reactor for aspect ratio, A in the range of 1.5 to 2.0 is found. The performance of a transmutation reactor is investigated and shows that a transmutation reactor with a neutron source producing fusion power less than 150 MW can destroy the transuranic actinides contained in the spent fuels produced from more than two 1 GWe PWRs with production of the fission power being greater than 2 GW.

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조직지식 창출프로세스에 관한 탐색적 연구 (An Exploratory Study on the Organizational Knowledge Discovery Process)

  • 김선아;김영걸
    • 지식경영연구
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    • 제1권1호
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    • pp.91-107
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    • 2000
  • This paper proposes the Organizational Knowledge Discovery Process Model (OK-DPM) as an initiative for developing a knowledge management methodology. OK-DPM is a model designed to effectively discover knowledge useful to the organization. It explains the knowledge discovery process from the conceptual level to the application level. It decomposes the organizational knowledge discovery process into 3 sub-processes; Creation, Suggestion and Validation. For each sub-process, design components are identified and possible methods for supporting each one are suggested. Also, the relationship patterns between the knowledge discovery process and knowledge type are explored. By applying OK-DPM to two real cases where the knowledge management projects are ongoing, the model was validated and revised. Even though we need to investigate with more cases to refine the OK-DPM, we found that it could provide some insights in developing the effective knowledge discovery process.

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스마트 무인기 연료시스템 설계 (Fuel System Design for Smart UAV)

  • 이창호
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2005년도 제25회 추계학술대회논문집
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    • pp.457-463
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    • 2005
  • 터보샤프트 엔진을 장착한 스마트무인기의 연료시스템을 설계하였다. 개념설계 단계의 설계방법을 기초로 하여 비행체의 상세설계가 진행되면서 기체구조설계로부터 도출된 탱크 배치와 구성설계를 하였다. 또한 연료시스템의 상세설계에 필요한 비행체 및 엔진의 데이터를 도출하여 연료시스템의 주요 구성요소인 연료공급계통, 연료탱크 벤트계통, 그리고 급유계통의 상세 설계를 수행하였다.

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모델 리파지토리를 이용한 기업지식경영 : P사 적용 사례를 중심으로 (Enterprise Knowledge Management Using Model Repository : P Company Case)

  • 정재우;이희석
    • 한국경영과학회지
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    • 제16권2호
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    • pp.33-33
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    • 1991
  • The management of enterprise knowledge has been increasingly important because knowledge emerges as the new basis of competition in postcapitalist society. One of the key issues in knowledge management is to put knowledge into a repository where it can be easily stored, reused, and recreated. This paper proposes a model repository and the corresponding knowledge management framework. The emphases of model repository is on abstraction knowledge in the form of schematic models. Two major benefits are model independence and model integration. A metaschema is constructed according to six conceptual components: separate unit, external link, internal link, separate unite descriptor, link descriptor, and composite descriptor, which can be applied for a variety of models. A prototype system with a case illustrates the practical usefulness of model repository for knowledge management

초내열합금 HIP 성형을 위한 금형설계 (Die design for HIP'ing of Nickel-base Superalloys)

  • 임정숙;염종택;;박노광
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2004년도 춘계학술대회 논문집
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    • pp.139-142
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    • 2004
  • Nickel base superalloys are widely used for high temperature applications due to heat resisting capability and corrosion resistance at high temperatures. Superalloys with many strengthening alloying elements are frequently used in powder form to alleviate harmful effects of alloy segregation. HIP (hot isostatic pressing) and DB (diffusion bonding) as a form of solid-state bonding process is used to make turbine components, such as integrated turbine rotors. HIP/DB process requires many technical overcomes related to dimensional changes as well as microstructural control. In this research, HIP/DB process for nickel base superalloys, Udimet 720 and MM 247, were investigated with a view to control the dimensional change during the consolidation process. Simple disc-shaped cans were used to select the conceptual die design for the control of the dimensional change especially in radial direction. The change in the shape of consolidated shape was investigated using commercial FE code with constitutive equations fur low temperature plasticity deformation.

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