• 제목/요약/키워드: a modeling

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바다양체 위상 표현을 바탕으로 한 박판 형상 모델링 및 솔리드로의 변환 (Sheet Modeling and Transformation of Sheet into Solid Based on Non-manifold Topological Representation)

  • Lee, S.H.;Lee, K.W.
    • 한국정밀공학회지
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    • 제13권7호
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    • pp.100-114
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    • 1996
  • In order to create a solid model more efficiently for a plastic or sheet metal product with a thin and constant thickness, various methods have been proposed up to now. One of the most typical approaches is to create a sheet model initially and then transform it into a solid model automatically for a given thickness. The sheet model as well as the transitive model in sheet modeling procedure is a non-manifold model. However, the previous methods adopted the boundary representations for a solid model as their topological framework. Thus, it is difficult to represent the exact adjacency relationship between topological entities and to implement the topological operations for sheet modeling and the transformation procedure of a sheet into a solid. In this paper, we proposed a sheet modeling system based on a non-manifold topological representation which can represent solids, sheets, wireframes, and their mixture. A set of generalized Euler operators for non-manifold topology as well as the sheet modeling capabilities including adding, bending, and punching functions are provided for easy modeling of sheet objects, and they are perfomed interactively with a two dimensional curve editor. Once a sheet model is completed, it can be transformed into a solid automatically. The transformation procedure is composed of the offset functions and the Boolean operations of sheet models, and it is even more comprehensive and easier to be implemented than the precious methods.

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수리 모형의 표현과 관리를 위한 다면적 접근법 (Multi-facetted Approach to Mathematical Model Representation and Management)

  • 김종우;김형도;박성주
    • 한국경영과학회지
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    • 제23권2호
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    • pp.157-185
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    • 1998
  • One of the essential issues in model systems is how to represent and manipulate mathematical modeling knowledge. As the bases of integrated modeling environments, current modeling frameworks have limitations: lack of facility to coordinate different users perpectives and lack of mechanism to reuse modeling knowledge. In this paper, multi-facetted modeling approach is proposed as a basis for the development of integrated modeling environment which provides facilities for (1) independent management of modeling knowledge from individual models; (2) object-oriented conceptual blackboard concept; (3) multi-facetted modeling; and (4) declarative representation of mathematical knowledge. The proposed multi-facetted approach is illustrated using multicommodity transportation models.

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능동소음제어를 이용한 고속철도 KTX의 내소음 저감을 위한 모델링에 관한 연구 (A Study on the Modeling for Reducing High-Speed Train KTX's Interior Noise using Active Noise Control Technique)

  • 김영민;이권순
    • 전기학회논문지
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    • 제61권11호
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    • pp.1725-1731
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    • 2012
  • In this paper, experiments were conducted to validate the importance and necessity of modeling. The modeling was performed using 120Hz and 280Hz noise of KTX main interior noise frequency. After the modeling, In order to solve the system instability by the additional path that exists between the control speaker and the error microphone, the secondary path was estimated. Next, simulations were performed to verify the modeling's necessity and importance. Thought the simulation results, we confirmed that the system with the modeling is more effective for noise reduction than without the modeling.

구조적 모델링을 위한 객체지향적 모델베이스 조직화 (On the Organization of Object-Oriented Model Bases for Structured Modeling)

  • 정대율
    • 한국정보시스템학회지:정보시스템연구
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    • 제5권
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    • pp.149-173
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    • 1996
  • This paper focus on the development of object-oriented model bases for Structured Modeling. For the model base organization, object modeling techniques and model typing concept which is similar to data typing concept are used. Structured modeling formalizes the notion of a definitional system as a way of dscribing models. From the object-oriented concept, a structured model can be represented as follows. Each group of similar elements(genus) is represented by a composite class. Other type of genera can be represented in a similar manner. This hierarchical class composition gives rise to an acyclic class-composition graph which corresponds with the genus graph of structured model. Nodes in this graph are instantiated to represent the elemental graph for a specific model. Taking this class composition process one step further, we aggregate the classes into higher-level composite classes which would correspond to the structured modeling notion of a module. Finally, the model itself is then represented by a composite class having attributes each of whose domain is a composite class representing one of the modules. The resulting class-composition graph represent the modular tree of the structured.

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Developing A Document-based Work-flow Modeling Support System A Case-based Reasoning Approach

  • Kim, Jaeho;Woojong Suh;Lee, Heeseok
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 2001년도 춘계정기학술대회
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    • pp.445-454
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    • 2001
  • A workflow model is useful fur business process analysis and has often been implemented for office automation through information technology. Accordingly, the results of workflow modeling need to be systematically managed as information assets. In order to manage the modeling process effectively, it is necessary to enhance the efficiency of their reuse. Therefore, this paper creates a Document-barred Workflow Modeling Support System (DWMSS) using a case-based reasoning (CBR) approach. It proposes a system architecture, and the corresponding modeling process is developed. Furthermore, a repository, which consists of a case base and vocabulary base, is built. A carte study is illustrated to demonstrate the usefulness of th is system.

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Wavelet operator for multiscale modeling of a nuclear reactor

  • Vajpayee, Vineet;Mukhopadhyay, Siddhartha;Tiwari, Akhilanand Pati
    • Nuclear Engineering and Technology
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    • 제50권5호
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    • pp.698-708
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    • 2018
  • This article introduces a methodology of designing a wavelet operator suitable for multiscale modeling. The operator matrix transforms states of a multivariable system onto projection space. In addition, it imposes a specific structure on the system matrix in a multiscale environment. To be specific, the article deals with a diagonalizing transform that is useful for decoupled control of a system. It establishes that there exists a definite relationship between the model in the measurement space and that in the projection space. Methodology for deriving the multirate perfect reconstruction filter bank, associated with the wavelet operator, is presented. The efficacy of the proposed technique is demonstrated by modeling the point kinetics nuclear reactor. The outcome of the multiscale modeling approach is compared with that in the single-scale approach to bring out the advantage of the proposed method.

네크워크분석을 위한 계산지모형 (A spreadsheet modeling for network analysis)

  • 이호창
    • 경영과학
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    • 제11권1호
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    • pp.59-72
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    • 1994
  • In this paper we examine potentials of a spreadsheet program, one of the most widly available software system, as a mathematical optimization modeling tool. For an illustrative example, a shortest path problem is modeled on Lotus-123 for practical use and an implementational framework and a general guide to the spreadsheet modeling of network analysis is provided.

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확장된 Petri-net을 이용한 FMS의 모델링 및 스케쥴링 (Modeling and scheduling for FMS using extended petri nets)

  • 안인석;서기성;우광방
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.488-492
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    • 1991
  • This paper deals with modeling and scheduling for flexible manufacturing systems(FMS). In modeling extended Petri nets are used to describe various and complex properties. To resolve multiple conflict without predefined properties, such as part selection, machine selection, rule-based scheduling method is introduced. This structure have a capability of on-line scheduling with systematic modeling description.

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인체장기의 정밀한 NURBS 곡면 모델링 사례연구 (A Case Study on Precise NURBS Modeling of Human Organs)

  • 김호찬;배용환;서태원;이석희
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.915-918
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    • 2005
  • Advances in Information Technology and in Biomedicine have created new uses for CAD technology with many novel and important biomedical applications. Such applications can be found, for example, in the design and modeling of orthopedics, medical implants, and tissue modeling in which CAD can be used to describe the morphology, heterogeneity, and organizational structure of tissue and anatomy. CAD has also played an important role in computer-aided tissue engineering for biomimetic design, analysis, simulation and freeform fabrication of tissue scaffolds and substitutes. And all the applications require precision geometry of the organs or bones of each patient. But the geometry information currently used is polygon model with none solid geometry and is so rough that it cannot be utilized for accurate analysis, simulation and fabrication. Therefore a case study is performed to deduce a transformation method to build free form surface from a rough polygon data or medical images currently used in the application. This paper describes the transformation procedure in detail and the considerations for accurate organ modeling are discussed.

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부가경로 전달함수의 온라인 예측에 의한 능동소음제어의 성능 향상 (Performance improvement of active noise control using on-line estimation of secondary path transfer function)

  • 김흥섭;손동구;오재응
    • 대한기계학회논문집A
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    • 제21권2호
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    • pp.281-287
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    • 1997
  • In the conventional inverse modeling method for on-line modeling of the secondary path transfer function, the signal to noise ratio between the arbitrary random signal and the plant noise have to keep at -10 - -20 dB. For these reasons, the modeling can't be exactly implemented by the conventional method alone and the convergence time for modeling becomes too long. In this study, by combining the conventional inverse modeling method with an adaptive line enhancer, or with an adaptive noise canceller, a rigorous transfer functions of secondary path modeling and the control of a primary noise have been implemented simultaneously.