• 제목/요약/키워드: models & modeling

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컴퓨터에 의해 수행되어지는 시뮬레이션 모델링을 위한 지식베이스 접근방법 (Knowledge-Based Approach for Computer-Aided Simulation Modeling)

  • 이영해;김남영
    • 산업공학
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    • 제2권2호
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    • pp.51-62
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    • 1989
  • A computer-aided simulation modeling system has been developed to allow the automatic construction of complete discrete simulation models for queueing systems. Three types of knowledge are used in the specification and construction of a simulation modeling: Knowledge of queueing system, simulation modeling, and a target simulation language. This knowledge has been incorporated into the underlying rule base in the form of extraction and construction rule, and implemented via the expert system building tool, OPS5. This paper suggested a knowledge based approach for automatic programming to enable a user who lacks modeling knowledge and simulation language expertize to quickly build executable models.

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Models and Modeling Behavior: A Look at the Critical Thinking Skills of Biology Majors

  • Partosa, Jocelyn D.
    • 한국과학교육학회지
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    • 제32권8호
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    • pp.1281-1294
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    • 2012
  • This paper describes the types of models that biology majors use and how they go about making their models in learning key concepts in biology such as the cell membrane, cytoskeleton and cell structure. Initially, a total of 44 biology students from all year levels enrolled in the second semester of calendar year 2008-2009 were asked to make their respective models of the cell membrane, cytoskeleton and cell structure. They were also asked to answer an open-ended questionnaire. Of the 44, only 20 (five from each year level) were randomly selected for a one-on-one interview. Results showed that the student-generated models from all year levels were mostly analogies, some textbook definitions and occasional drawings. In making their model, students first read the text; second, outline similarities in structure and function or both; and third, make the model. Data suggest that models are good diagnostic tools for identifying critical thinking skills of students. In this case, students mostly demonstrate the ability to recognize similarities in structure and function between the concept and their model. Some senior students demonstrated integration and reflective thinking in making their models. Thus, more opportunities for student-generated models must be available if students were to develop integration and reflective thinking in their models.

SYSTEMS STUDIES AND MODELING OF ADVANCED LIFE SUPORT SYSTEM

  • Kang, S.;Ting, K.C.;Both, A.J.
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.III
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    • pp.623-631
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    • 2000
  • Advanced Life Support Systems (ALSS) are being studied to support human life during long-duration space missions. ALSS can be categorized into four subsystems: Crew, Biomass Production, Food Processing and Nutrition, Waste Processing and Resource Recovery. The System Studies and Modeling (SSM) team of New Jersey-NASA Specialized Center of Research and Training (NJ-NSCORT) has facilitated and conducted analyses of ALSS to address systems level issues. The underlying concept of the SSM work is to enable the effective utilization of information to aid in planning, analysis, design, management, and operation of ALSS and their components. Analytical tools and computer models for ALSS analyses have been developed and implemented for value-added information processing. The results of analyses have been delivered through the Internet for effective communication within the advanced life support (ALS) community. Several modeling paradigms have been explored by developing tools for use in systems analysis. They include object-oriented approach for top-level models, procedural approach for process-level models, and application of commercially available modeling tools such as MATLAB$\^$(R)//Simulink$\^$(R)/. Every paradigm has its particular applicability for the purpose of modeling work. An overview is presented of the systems studies and modeling work conducted by the NJ-NSCORT SSM team in its efforts to provide systems analysis capabilities to the ALS community. The experience gained and the analytical tools developed from this work can be extended to solving problems encountered in general agriculture.

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Systems Studies and Modeling of Advanced Life Support Systems

  • Kang, S.;Ting, K.C.;Both, A.J.
    • Agricultural and Biosystems Engineering
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    • 제2권2호
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    • pp.41-49
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    • 2001
  • Advanced Life Support Systems(ALSS) are being studied to support human life during long-duration space missions. ALSS can be categorized into four subsystems: Crew, Biomass Production, Food Processing and Nutrition, Waste Processing and Resource Recovery. The System Studies and Modeling (SSM) team of New Jersey-NASA Specialized Center of Research and Training (NJ-NSCORT) has facilitated and conducted analyses of ALSS to address systems level issues. The underlying concept of the SSM work is to enable the effective utilization of information to aid in planning, analysis, design, management, and operation of ALSS and their components. Analytical tools and computer models for ALSS analyses have been developed and implemented for value-added information processing. The results of analyses heave been delivered through the internet for effective communication within the advanced life support (ALS) community. Several modeling paradigms have been explored by developing tools for use in systems analysis. they include objected-oriented approach for top-level models, procedureal approach for process-level models, and application of commercially available modeling tools such as $MATLAB^{R}$/$Simulink^{R}$. Every paradigm has its particular applicability for the purpose of modeling work. an overview is presented of the systems studies and modeling work conducted by the NJ-NSCORT SSM team in its efforts to provide systems analysis capabilities to the ALS community. The experience gained and the analytical tools developed from this work can be extended to solving problems encountered in general agriculture.

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컴포넌트 추출을 위한 UML 기반의 역할 모델링에 관한 연구 (A Study on UML-Based Role Modeling for Extracting Components)

  • 송호영;김정종
    • 정보처리학회논문지D
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    • 제11D권3호
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    • pp.591-596
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    • 2004
  • 컴포넌트 소프트웨어 개발에서 양질의 컴포넌트를 추출하기 위해서는 사용자의 요구사항을 정확하게 표현할 수 있는 체계적인 모델링 방법이 필요하다. 피러나 컴포넌트는 일반적으로 객체 모델링을 기반으로 설계되고 개발되기 때문에 상호작용과 협력의 표현, 상속으로 인한 재사용 문제 등을 해결하는데는 한계가 있으며 복잡한 구조를 가진 대규모 시스템에서 컴포넌트를 추출하기에는 용이하지 않다. 따라서 객체 모델링을 보완하기 위하여 객체 중심이 아닌 객체의 역할을 중심으로 하는 역할 모델링 기법을 활용할 필요가 있다. 역할 모델링은 대체들의 패턴을 추상화하고 복잡한 대규모 시스템을 관계의 분리를 통하여 간단한 모델로 생성할 수 있도록 객체의 역할을 중심으로 모델링하는 기법이다. 본 논문은 UWL 기반에서 역할 모델링을 통하여 컴포넌트를 추출하는 방법을 연구한다. UML은 다양한 관점으로 모델을 표현하고 있으므로 다양한 관점의 역할 모델을 표현하여 컴포넌트를 추출하는데 활용할 수 있도록 한다.

국방 Modeling & Simulation에서 임무공간 개념모델링을 위한 온톨로지 적용방안 (An Ontological Approach for Conceptual Modeling of Mission Space in Military Modeling & Simulation)

  • 배영민;강혜란;이종혁;이경호;이영훈
    • 정보화연구
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    • 제9권3호
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    • pp.243-251
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    • 2012
  • 본 논문은 온톨로지 기반의 임무공간 개념 모델링 체계인 한국형 임무공간 개념모델 (CMMSK:The Conceptual Models of the Mission Space-Korea)을 제안한다. 모델링과 시뮬레이션을 이용하면 실제 군사 훈련을 실행할 때 발생하는 시간, 공간 그리고 경제적인 비용을 크게 줄일 수 있다. CMMS-K는 국방 모델과 시뮬레이션의 상호운용성과 재사용성을 향상시키기 위해 개발되고 있다. CMMS-K의 구조는 한국 국방 환경을 기반으로 기존 국방 개념 모델링 체계를 참조하여 생성되었다. CMMS-K의 주요 구성요소는 도메인 온톨로지, 임무공간 모델 기술 언어, 임무공간 모델링 도구, 그리고 CMMS-K 관리 시스템이다. CMMS-K 도메인 온톨로지는 개체 및 과제 온톨로지로 구성된다. 본 논문은 CMMS-K 도메인 온톨로지에 대해서 자세히 기술하고 제안된 방법의 적용 가능성을 예제를 이용하여 평가한다.

선형기반 터널 인프라 구조물의 BIM 모델링 자동화 알고리즘 개선 및 BIM 모델링 자동화 시스템 개발 (Enhancement of BIM Modeling Automation Algorithm for Linear-Based Tunnel Infrastructure and Development of BIM Modeling Automation System)

  • 김윤옥;김지영;김태민;문소영
    • 한국BIM학회 논문집
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    • 제13권3호
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    • pp.1-11
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    • 2023
  • In order to use BIM as a tool for improving the productivity and quality of products in the construction industry, a BIM model must be created from the design stage first. Infrastructure structures such as bridges and tunnels are mainly created based on three-dimensional alignment in the generation of BIM models. Especially, generation of BIM models based on three-dimensional linearity has high task difficulty and algorithms for automating BIM modeling for railway infra structures have been suggested in previous studies. This study improved the BIM modeling automation algorithm of railway infrastructures and developed a system based on the algorithm so that it can be easily used by ordinary users. The system was built as an add-in system of Autodesk's Revit. As an improvement first, it is possible to arrange different libraries for each pattern, enabling various uses. In addition, it can be created models of several members with a single process and the system can automatically places structures that are added periodically, such as Rock Bolt and Fore Polling. Finally, 3D length information and volume for each pattern are automatically calculated for more accurate 3D-based volume calculation. This study contributes to increasing user accessibility by building a BIM modeling automation algorithm into a system. The system is expected to improve the efficiency of BIM modeling creation of linear-based infra structures, including railway infrastructure.

Empirical Modeling of Steering System for Autonomous Vehicles

  • Kim, Ju-Young;Min, Kyungdeuk;Kim, Young Chol
    • Journal of Electrical Engineering and Technology
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    • 제12권2호
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    • pp.937-943
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    • 2017
  • To design an automatic steering controller with high performance for autonomous vehicle, it is necessary to have a precise model of the lateral dynamics with respect to the steering command input. This paper presents an empirical modeling of the steering system for an autonomous vehicle. The steering system here is represented by three individual transfer function models: a steering wheel actuator model from the steering command input to the steering angle of the shaft, a dynamic model between the steering angle and the yaw rate of the vehicle, and a dynamic model between the steering command and the lateral deviation of vehicle. These models are identified using frequency response data. Experiments were performed using a real vehicle. It is shown that the resulting identified models have been well fitted to the experimental data.

Stochastic Petri Nets Modeling Methods of Channel Allocation in Wireless Networks

  • Ro, Cheul-Woo;Kim, Kyung-Min
    • International Journal of Contents
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    • 제4권3호
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    • pp.20-28
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    • 2008
  • To obtain realistic performance measures for wireless networks, one should consider changes in performance due to failure related behavior. In performability analysis, simultaneous consideration is given to both pure performance and performance with failure measures. SRN is an extension of stochastic Petri nets and provides compact modeling facilities for system analysis. In this paper, a new methodology to model and analyze performability based on stochastic reward nets (SRN) is presented. Composite performance and availability SRN models for wireless handoff schemes are developed and then these models are decomposed hierarchically. The SRN models can yield measures of interest such as blocking and dropping probabilities. These measures are expressed in terms of the expected values of reward rate functions for SRNs. Numerical results show the accuracy of the hierarchical model. The key contribution of this paper constitutes the Petri nets modeling techniques instead of complicate numerical analysis of Markov chains and easy way of performance analysis for channel allocation under SRN reward concepts.

간결하고 효율적인 폴리곤 메쉬의 표현 구조 (A Compact and Efficient Polygonal Mesh Representation)

  • 박상근;이상헌
    • 한국CDE학회논문집
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    • 제9권4호
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    • pp.294-305
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    • 2004
  • Highly detailed geometric models are rapidly becoming commonplace in computer graphics and other applications. These complex models, which is often represented as complex1 triangle meshes, mainly suffer from the vast memory requirement for real-time manipulation of arbitrary geometric shapes without loss of data. Various techniques have been devised to challenge these problems in views of geometric processing, not a representation scheme. This paper proposes the new mesh structure for the compact representation and the efficient handling of the highly complex models. To verify the compactness and the efficiency, the memory requirement of our representation is first investigated and compared with other existing representations. And then we analyze the time complexity of our data structure by the most critical operation, that is, the enumeration of the so-called one-ring neighborhood of a vertex. Finally, we evaluate some elementary modeling functions such as mesh smoothing, simplification, and subdivision, which is to demonstrate the effectiveness and robustness of our mesh structure in the context of the geometric modeling and processing.