• Nuclear Engineering and Technology
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• 제49권1호
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• pp.92-102
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• 2017

The analysis of steam generators as an interface between primary and secondary circuits in light water nuclear power plants is crucial in terms of safety and design issues. VVER-1000 nuclear power plants use horizontal steam generators which demand a detailed thermal hydraulics investigation in order to predict their behavior during normal and transient operational conditions. Two phase flow field simulation on adjacent tube bundles is important in obtaining logical numerical results. However, the complexity of the tube bundles, due to geometry and arrangement, makes it complicated. Employment of porous media is suggested to simplify numerical modeling. This study presents the use of porous media to simulate the tube bundles within a general-purpose computational fluid dynamics code. Solved governing equations are generalized phase continuity, momentum, and energy equations. Boundary conditions, as one of the main challenges in this numerical analysis, are optimized. The model has been verified and tuned by simple two-dimensional geometry. It is shown that the obtained vapor volume fraction near the cold and hot collectors predict the experimental results more accurately than in previous studies.

• Water Engineering Research
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• 제7권1호
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• pp.9-20
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• 2006

The watersheds are functional geographical areas that integrate a variety of environmental and ecological processes and human impacts on landscapes. Geographical assessments using GIS recognize the relationship between interdependence of resources and ecological/environmental components in watersheds. They are useful methodology for viable long term natural resource management. This paper performs through the using hydrological analyses, landscape ecological analyses, remote sensing, and GIS. Indicators are items or measures that represent key components of the small watersheds, and they are developed to be evaluated. Some indicators are described that they represent watershed condition and trend as well as focus on physical, biological and chemical properties of small watershed. Also, ecological functions such as stability, resilience, and sensitivity are inferred from them. The model implemented in GIS allows to reflect the ecological and hydrological functioning of watershed. Methodology from image analysis, landscape ecological analysis, spatial interpolation, and numerical process modeling are integrated within GIS to provide assessment for eco-logical/environmental condition. Results are described from the small watershed of Gwynns Falls in Baltimore County and Baltimore City, Maryland, an area of about 66.5 square miles. The small watershed within Gwynns Falls watershed are subject to a number of land-use. But it is predominantly urban, with significantly lesser amounts of forest and agriculture. The increasing urbanization is ass-coiated with ecological/environmental impacts and citizen conflicts.

• 한국통신학회논문지
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• 제17권8호
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• pp.823-836
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• 1992

앞으로의 컴퓨터 네트워크는 여러 서비스를 통합하여 제공할 수 있는 통신망인 종합정보 통신망으로 발전해 갈 것이다. 이에 따라 현재 운영되고 있는 컴퓨터망이 ISDN에 접속되어 사용하는 것은 매우 중요한 문제로 부각될 것이다. 본 논문은 근거리 통신망과 ISDN의 연동화 방안을 연구하였다. 이를 위하여 기존의 근거리 통신망과 ISDN의 특성에 관하여 분석하고 연동을 위하여 고려해야 할 사항을 검토하였으며 Co와 CL서비스에 대한 연동방안을 제시하였다.이를 구체화하여 근거리 통신망과 ISDN을 연동하는 게이트웨이를 논리적으로 구성하였고, 그 연동과정을 페트리네트로 모델링하였으며 도달트리를 구성하여 프로토콜의 정확성을 검증하였다. 본 연구가 근거리 통신망과 종합 정보 통신망을 연동하는 게이트 웨이의 설계와 구현을 위하여 유용하게 이용될 수 있을 것이다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.439-442
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• 2004

기존의 비디오 데이터베이스 시스템들은 대부분 간단한 간격을 기반으로 한 관계와 연산을 지원하는 모델을 이용하였다. 비디오 모델에서 시간을 지원하고 객체와 시간의 다양한 연산을 제공하며 효율적인 검색과 브라우징을 지원하는 비디오 데이터 모델이 필요하게 되었다. 비디오 모델은 객체 지향 개념을 기반으로 한 모델로서 비디오의 논리적인 스키마, 객체의 속성과 연산 관계, 그리고 상속과 주석을 이용한 메타데이터 설계를 통하여 비디오 데이터에 대한 전체적인 모델 구조를 제시하였다. 그리고, 점 시간과 시간 간격을 정의하여 시간의 개념을 객체 지향 기반 모델에 부여함으로서 시간 변화에 따른 비디오 정보를 보다 효율적으로 활용할 수 있도록 하였다.

• 한국군사과학기술학회지
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• 제15권6호
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• pp.754-760
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• 2012

To improve the efficiency and economics of national defence, the needs for defence M&S systems are greatly increased, but the lack of interoperability and reusability lowers the level of reliability in the existing simulations models. Recently, many research activities have been performed and some conceptual models, such as CMMS, DCMF, and KAMA, were introduced. However, these models don't support the whole process of defence M&S system development nor provide integrated domain knowledge and up-to-date data. In this paper, we analyzed the analysts' guidances and doctrines, which are the basic ingredients for the simulation system development, and proposed a systematic structure for all the defence M&S stakeholders to share the standardized domain knowledge, modeling algorithm and data. This will be a logical bridge between Mission Space and Simulation Space, and provide substantial data sets to build simulation systems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.220-222
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• 2004

In the paper architecture of load flow under graphic interface we mentioned that the define of graphic interface and the way of system modeling. In the view point of engineering, domain define is the step of process which is seek out the general solution. This is a base of program's structure. When making a relationship inner component, relevance and restriction are affected by data type and etc. In this process logical data is realized as a symbol. And system configuration decide that main function and extension by the analysis user's demand and requirements. Specially engineering analysis software has accuracy also through the numerical method. To represent this wee need more powerful graphical component. This helps user's accessibility. We can combine 10, numerical library and graphical component as a system element by domain definition. In this paper we will materialize as a step of implementation and decide a direction of programming. In conclusion we will see the analysis software's necessary function to make a better.

• 한국IT서비스학회지
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• 제7권4호
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• pp.45-60
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• 2008

Networked enterprise (NE) is an organization of independent companies that collaborate with each other temporary or permanently for accomplishing common goals. The USA and EU have been developing principal concepts, techniques, and solutions to enhance the competitiveness of traditional industries including small-and-medium enterprises (SMEs). In Korea, however, implementation as well as R&D of NE is very few, which we believe comes from lack of understanding on Its meaning and lack of effective information systems for it. This paper is to suggest an Enterprise Architecture (EA) framework or reference model of NE and an Information Technology Architecture (ITA) of NE. The EA framework will help stakeholder of NE (e,g., policy makers, members of NE, IT solution providers, and researchers) understand structural and behavioral characteristics of NE. The ITA will be used as a guideline of developing information systems for NE that is essential for spreading networked business models, The focus of this paper is not on logical-level design but on conceptual-level modeling of NE. As verification of the suggested framework and architecture is still required, so we'll apply them to various manifestations of NE, e.g., dynamic supply chain, vertical integration of extended enterprises, and P2P-style virtual enterprises.

• Asian Journal of Innovation and Policy
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• 제9권3호
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• pp.281-307
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• 2020

A variety of approaches are being applied to improve the existing ex-ante evaluation by expert panels in publicly funded R&D. While the objective evaluation criteria are constantly being improved to screen and select the superior projects, alternative approaches such as random prioritization and logical modeling are also underway to overcome the conservative bias of reviewers and to secure disruptive innovation. This study intends to find critical implications for ex-ante evaluation of public R&D system from the comparison of Indonesia and Korea. For the comparative analysis, literature review and expert in-depth interviews are conducted on the national R&D system and the selection evaluation process. In Korea, the selection criteria of projects are legally promulgated for establishing an objective evaluation system, and at the program level, the major considerations in the planning process are specified by Presidential Decree. On the other hand, while Indonesia conducts R&D in 47 strategic fields largely by public research institutes (PRI) based on the non-competitive government contributions. This study draws out implications of institutionalizing the planning process at the level of program, and of increasing the ratio of contract-based competitive funding at the level of project in the national R&D portfolio.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.426-432
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• 2013

The construction industry consists of various and massive architectural information as an architectural process includes a variety of design stages with cooperation of many disciplines. Particularly, architectural information is generated and managed through the life cycle of a building, from conceptual design stage to the construction and maintenance. A Building Information Model (BIM) serves as a shared knowledge resource for information about a facility forming a reliable basis for decisions during its life-cycle from inception onward. BIM technology accomplished quantitative development being utilized in various disciplines. However, it is necessary to develop environment and requirement for qualitative improvement of BIM based project. Particularly, requirement is very important for architectural design evaluations. The purpose of this study is to develop and apply of quality control requirement for improving the quality of architectural design in open BIM environments. To achieve this purpose, the authors have investigated case study for open BIM data quality control (software, guideline and application case) and classified quality control targets according to physical/logical quality and data quality. In addition, the authors have defined open BIM based quality control process and developed quality control requirements. Finally, the authors have developed rule based quality check system using requirements for efficient quality control based on open BIM.

• 사물인터넷융복합논문지
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• 제7권2호
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• pp.13-19
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• 2021

에너지 패턴은 국가 경제 침체에 따라 에너지 소비가 감소한 질병 트렌드의 사회 문제에 영향을 받는 것으로 분석됩니다. 사람들을 위한 사회적 거리 캠페인은 2019 년 코로나 바이러스 질병 (COVID-19)의 전염병으로 인해 자발적으로 또는 법적으로 수행되었습니다. 미국, 한국 등 일부 국가에서 일부 경제 부양 정책이 시행되었습니다. S, I, R로 논리적 모델링이 구성되는 시스템 역학 (SD)에 의해 적용된 SIR (Sceptible, Infectious, Recovery) 모델링을 보여줍니다. 특히 I 는 인구, 인종, 성숙도를 포함한 사회와 연결되어 있습니다. 또한 경제 및 정치는 소득, GDP, 자원, 대통령, 인기, 통치 정부 및 리더십과 관련이 있습니다. 그래프는 S 값 곱셈이 시작되는 2020년 4월의 큰 도약을 보여줍니다. 이것은 COVID-19의 영향과 관련 유행병 이후 추세를 보여줍니다. OECD와 비 OECD의 경향은 매우 유사하며 바이러스 위험의 영향은 경제 침체를 크게 유발합니다.