• 제목/요약/키워드: conceptual data model

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수학 탐구학습에서 지식 형성에 대한 연구 (Knowledge Construction on Mathematics Problem Solving)

  • 이중권
    • 한국수학사학회지
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    • 제17권3호
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    • pp.109-120
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    • 2004
  • 이 연구는 학과 과제와 기말 프로젝트에 있는 문제들 중에서 컴퓨터를 활용하여 수학적 문제 해결을 해 가는 세 명의 예비 교사를 연구 조사하였다 모든 연구 참여자들의 활동과 컴퓨터를 활용한 문제 해결 과정을 관찰하고 촬영하였다. 가능한 경우 예비 교사들의 탐구활동 전과 후 및 탐구활동 중에 개별적인 면담을 하였다. 자료수집 방법은 관찰, 면담, 현장 기록, 제출과제, 컴퓨터 작업, 오디오와 비디오 테이프를 사용하였다. 수학적 문제 해결 초기 단계에서는, 모든 연구 참여자들이 그래프와 데이터를 사용하여 모델 만들기, 사인 함수의 일반적 개념에 대하여 절차적 지식과 개념적 지식이 약하게 형성되어 있었으나 컴퓨터를 활용한 수학적 문제 해결 활동을 통하여 그들은 절차적 지식과 개념적 지식을 강하게 구성하였고 그들을 적절하게 연계시킬 수 있었다

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Causal and Intervening Conditions of Korean Immigrants' Sport Participation in the United States

  • KIM, Nam-Su;KIM, Min Soo;SEO, Won Jae
    • Journal of Sport and Applied Science
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    • 제6권2호
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    • pp.19-25
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    • 2022
  • Purpose: This study attempts to investigate causal and intervening conditions for sport participation of Korean immigrants in the United States. Research design, data, and methodology: Grounded theory approach was used to develop a conceptual framework that presents the psychosocial processes that occur in immigrants' experience of sport participation. Participants were selected purposefully for information-rich cases. Korean immigrants with current experience of having periodically participated in sports were the criterion for sample selection. Based on selection criteria, 9 Korean immigrants took part in interview. The interview discussions were taped and transcribed verbatim into a Word file. The process for data analysis included four grounded theory approaches of purposive and theoretical sampling, an open and axial coding, memo writing, and finally the development of the conceptual framework. Results: Six concepts were revealed in the causal conditions that facilitate the process of immigrants' sport participation in the states: Personal experience, significant others, personality, physical environment, psychological well-being, and social connection. Three concepts were revealed as the intervening conditions that block the process of immigrants' sport participation in the states: Conflict with cultural change of organization, Pressure at workplace, and Economic constraints. Conclusions: Conceptual model presents causal and intervening factors. Further implications were discussed.

교량 계측 정보 관리를 위한 데이터베이스 설계 (The Database Design for the Management of Bridge Measurement Information)

  • 황진하;박종회;조대현
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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    • pp.126-132
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    • 2004
  • The database design for the management of bridge measurement information is presented in this paper. To express the associated data generated during the whole process of ambient measurement efficiently, requirements analysis for database construction is performed. And to define objects and organize schema conceptual and logical design are performed, which convert data model into logical schema. Finally, physical design is performed using DDL(data defined language). This database is based on the object-relational data modeling approach that has rich expressive power and good reusability in comparison with the traditional entity-relational modeling.

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연구용원자로 기본설계에 대한 예비 확률론적 안전성 평가 (Aspects of Preliminary Probabilistic Safety Assessment for a Research Reactor in the Conceptual Design Phase)

  • 이윤환
    • 한국안전학회지
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    • 제34권3호
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    • pp.102-110
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    • 2019
  • This paper describes the work and results of the preliminary Probabilistic Safety Assessment (PSA) for a research reactor in the design phase. This preliminary PSA was undertaken to assess the level of safety for the design of a research reactor and to evaluate whether it is probabilistically safe to operate and reliable to use. The scope of the PSA described here is a Level 1 PSA which addresses the risks associated with core damage. After reviewing the documents and its conceptual design, eight typical initiating events are selected regarding internal events during the normal operation of the reactor. Simple fault tree models for the PSA are developed instead of the detailed model at this conceptual design stage. A total of 32 core damage accident sequences for an internal event analysis were identified and quantified using the AIMS-PSA. LOCA-I has a dominant contribution to the total CDF by a single initiating event. The CDF from the internal events of a research reactor is estimated to be 7.38E-07/year. The CDF for the representative initiating events is less than 1.0E-6/year even though conservative assumptions are used in reliability data. The conceptual design of the research reactor is designed to be sufficiently safe from the viewpoint of safety.

지구과학교육 분야의 개념변화 연구 동향 분석 (Analysis of Research Trend on Conceptual Change in Earth Science)

  • 박기락;박현주
    • 한국지구과학회지
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    • 제39권2호
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    • pp.193-207
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    • 2018
  • 본 연구의 목적은 우리나라에서 수행된 지구과학교육 분야의 개념변화 연구 동향을 분석하여 향후 개념변화 연구의 기초 자료로 제공하는 것이다. 우리나라 지구과학 개념변화 연구의 경향성을 논문의 키워드, 발표 연도, 논문 출처, 연구 목적, 연구 대상, 연구 영역, 연구 방법 측면에서 분석하였다. 연구 대상은 우리나라 지구과학교육의 개념변화연구 논문이 처음 발표된 1989년부터 2017년 7월까지, 총 126편의 지구과학교육의 개념변화 논문이었다. 본 연구의 분석 결과는 다음과 같다. 첫째, 지구과학 개념변화 논문은 '개념변화'라는 용어를 '오개념', '선개념' 보다 더 많이 사용하였다. 둘째, 개념변화 논문은 2000년대에 많은 양적인 성장을 이루었다. 셋째, 개념변화는 석사 학위의 연구주제로 많이 이루어지고 있었다. 넷째, 오개념 조사와 그에 따른 교정을 함께 다룬 연구가 많았고, 오개념 조사로는 자유응답 검사법을, 오개념 교정 방법으로는 인지갈등 수업모형과 CAI 교수전략을 주로 활용하였다. 다섯째, 초등학생 대상 연구가 가장 많이 이루어졌다. 여섯째, 개념변화 연구의 지구과학 영역은 천문과 대기의 비중이 높았다. 마지막으로, 연구 초기에는 양적 분석 방법을 많이 사용하였지만, 2010년대에 들어서는 질적 분석 방법을 많이 사용하였다. 향후 개념변화의 연구 과제로 예비 및 현직 교사 대상의 개념변화 연구, 지질 해양 대기 등 다양한 영역으로의 연구 확대, 오개념 형성원인 파악 및 정의적 요인에 관한 연구 등을 제안하였다.

ESTIMATING COSTS DURING THE INITIAL STAGE OF CONCEPTUAL PLANNING FOR PUBLIC ROAD PROJECTS: CASE-BASED REASONING APPROACH

  • Seokjin Choi;Donghoon Yeo;Seung H. Han
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.1183-1188
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    • 2009
  • Estimating project costs during the early stage of conceptual planning is very important when deciding whether to approve the project and allocate an appropriate budget. However, due to greater uncertainties involved in a project, it is challenging to estimate costs during this initial stage within a reasonable tolerance. This paper attempts to develop a cost-estimate model for public road projects under these circumstances and limitations. In the conceptual planning stage of a road project, there is only limited information for cost estimation, for example, such input data as total length of the route, origin and destination, number of lanes, general geographic characteristics of the route, and other basic attributes. This implies that the model should individuate suitable but restricted information without considering detailed features such as quantity of earthwork and a detailed route of a given condition. With these limited facts, this paper applies a case-based reasoning (CBR) method to solve a new problem by deriving similar past problems, which in turn is used to estimate the cost of a given project based on best-fitted previous cases. To develop a CBR cost-estimate model, the authors classified 8 representative variables, including project type, the number of lanes, total length, road design grades, etc. Then, we developed the CBR model, primarily by using 180 actual cases of public road projects, procured over the last decade. With the CBR model, it was found that the degree of error in estimation can be reasonably reduced, to below approximately 30% compared to the final costs estimated upon the completion of detailed design.

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Discussion on Spatio-temporal Modeling

  • Tingting, Mao;Yu, Liu;Baojia, Lin;Lun, Wu
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.178-181
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    • 2003
  • The temporal GIS data modeling methods are discussed in this paper. At first, two conceptual models of spatio-temporal data are introduced, and then some typical STDMs based on these two models are summed up and compared. After that, the spatio-temporal changes are analyzed thoroughly, and then how to model spatio -temporal data from different aspects is discussed. At last, several issues that need further research are pointed out.

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STATISTICALLY PREPROCESSED DATA BASED PARAMETRIC COST MODEL FOR BUILDING PROJECTS

  • Sae-Hyun Ji;Moonseo Park;Hyun-Soo Lee
    • 국제학술발표논문집
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    • The 3th International Conference on Construction Engineering and Project Management
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    • pp.417-424
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    • 2009
  • For a construction project to progress smoothly, effective cost estimation is vital, particularly in the conceptual and schematic design stages. In these early phases, despite the fact that initial estimates are highly sensitive to changes in project scope, owners require accurate forecasts which reflect their supplying information. Thus, cost estimators need effective estimation strategies. Practically, parametric cost estimates are the most commonly used method in these initial phases, which utilizes historical cost data (Karshenas 1984, Kirkham 2007). Hence, compilation of historical data regarding appropriate cost variance governing parameters is a prime requirement. However, precedent practice of data mining (data preprocessing) for denoising internal errors or abnormal values is needed before compilation. As an effort to deal with this issue, this research proposed a statistical methodology for data preprocessing and verified that data preprocessing has a positive impact on the enhancement of estimate accuracy and stability. Moreover, Statistically Preprocessed data Based Parametric (SPBP) cost models are developed based on multiple regression equations and verified their effectiveness compared with conventional cost models.

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RTDDB 시스템에서의 감사 및 통제 (The audit and control of real time distributed data base system)

  • 배청홍
    • 산업경영시스템학회지
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    • 제12권19호
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    • pp.89-98
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    • 1989
  • This research addresses the most sophisticated level of complexity of current electronic data processing(EDP) technology realtime, distributed data base(DDB) system. The major objective is to develop guidelines for the control and audit of these sophisticated system, since the control and audit philosophies, control features, and audit techniques applicable to traditional EDP systems are no longer fully appropriate for, or relevant to, these stat-of-art systems. An attempt is made to develop an internally consistent audit and control Conceptual Framework summarizing and integrating the material developed in this research, which then leads into the analysis of the control and audit model.

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韓國 河川의 日 流出量 模型 (Daily Streamflow Model for the Korean Watersheds)

  • 김태철;박승기;안병기
    • 물과 미래
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    • 제29권5호
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    • pp.223-233
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    • 1996
  • 우리나라의 강수와 유역특성을 고려하여 일강우량과 증발량의 입력자료로 일유출량을 모의발생할 수 있는 "한국 하천의 일 유출량 모형(DAWAST)"을 개발하였다. 이 모형은 개념화 모형을 기본모형으로 최적화모형, 일반화모형 및 수계화모형 등 3개의 부모형으로 구성되어 있다. 기본모형은 유역을 지표면, 불포화층과 포화층의 3개 저수층으로 단순화하고 각 저수층에서 일단위로 물수지를 분석하였다. 최적화모형은 관측유출자료가 있는 유역에서 최적화기법으로 매개변수를 보정하여 적용하고, 일반화모형은 유역특성인자로부터 매개변수를 예측하여 미계측 중, 소유역에 적용하고, 수계화모형은 유역특성인자 조사가 없거나 어려운 지점에서 최적화기법으로 분석된 수문지점의 매개변수를 전용하여 미계측 대유역에 적용하여 일유출량을 추정한다.유출량을 추정한다.

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