• Title/Summary/Keyword: a modeling

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A Study on the modeling of roller gear cam (롤러기어캠의 모델링에 관한 연구)

  • 조승래;이춘만;정원지
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.10 no.3
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    • pp.31-37
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    • 2001
  • In this paper, we developed an automated program for the modeling and simulation of three-dimensional roller gear cam mechanisms. The three-dimensional modeling for a roller-gear cam employs coordinate transformations based on the con-tact condition. the wire frame modeling followed by the shading technique using triangular meshing elements incorporat-ed the to reduce the number of data and computational load. Computer simulations for two kinds of products for rollger-gear cam mechansim illustrate the relative motion between the modeled roller-gear cam and a turret and thus show the effectiveness of the proposed modeling.

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Wastewater process modeling

  • Serdarevic, Amra;Dzubur, Alma
    • Coupled systems mechanics
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    • v.5 no.1
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    • pp.21-39
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    • 2016
  • Wastewater process models are the essential tools for understanding relevant aspects of wastewater treatment system. Wastewater process modeling provides more options for upgrades and better understanding of new plant design, as well as improvements of operational controls. The software packages (BioWin, GPS-X, Aqua designer, etc) solve a series of simulated equations simultaneously in order to propose several solutions for a specific facility. Research and implementation of wastewater process modeling in combination with computational fluid dynamics enable testing for improvements of flow characteristics for WWTP and at the same time exam biological, physical, and chemical characteristics of the flow. Application of WWTP models requires broad knowledge of the process and expertise in modeling. Therefore, an efficient and good modeling practice requires both experience and set of proper guidelines as a background.

Modeling Techniques for Geoenvironmental Engineering Problems

  • Singh, D.N.;Rao, B. Hanumantha
    • Proceedings of the Korean Geotechical Society Conference
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    • 2007.09a
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    • pp.542-557
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    • 2007
  • Contamination of subsurface results in degradation of geomaterials (i.e., soils and rock mass), in the long run. This is mainly due to the presence of chemical and/or radiological materials in undesirable concentrations and at elevated temperatures. However, as contaminant-geomaterial interaction is an extremely slow and complex process, which primarily depends on their physical, chemical and mineralogical properties, it is quite difficult to study this interaction under laboratory or in situ conditions. In such a situation, accelerated physical modeling, using a geotechnical centrifuge, and finite element/difference based numerical modeling techniques are found to be quite useful. This paper presents details of various modeling techniques developed by the researchers at the Indian Institute of Technology Bombay, Mumbai, India, for studying heat migration, flow and interaction (fate) of reactive and non-reactive contaminants in the geoenvironment, under saturated and unsaturated conditions. In addition, paper presents details of the technique that can be employed for determining susceptibility of a material to undergo physico-chemico-mineralogical alterations due to its interaction with contaminants.

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Personalized Face Modeling for Photorealistic Synthesis

  • Kim, Kyungmin;Shim, Hyunjung
    • Journal of International Society for Simulation Surgery
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    • v.2 no.2
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    • pp.47-51
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    • 2015
  • Faces play a key role in revealing the personalized attributes such as the identity, emotion, health condition, etc. Due to the importance of faces, computer-assisted face modeling and reconstruction have been actively studied both in computer vision and graphics community. Especially, face reconstruction and realistic face synthesis are well-grounded research problems and various approaches have been proposed during the last decade. In this paper, we discuss a wide range of existing work in face modeling by introducing their target applications, categorizing them upon their methodology and addressing their strength and weakness on performance. Finally, we introduce remaining research issues and suggest the future research direction in face modeling. We believe that this paper provides a high-level overview on face modeling techniques and helps understand the major research issues and the trends of methodology.

Performability Analysis of Token Ring Networks using Hierarchical Modeling

  • Ro, Cheul-Woo;Park, Artem
    • International Journal of Contents
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    • v.5 no.4
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    • pp.88-93
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    • 2009
  • It is important for communication networks to possess the capability to overcome failures and provide survivable services. We address modeling and analysis of performability affected by both performance and availability of system components for a token ring network under failure and repair conditions. Stochastic reward nets (SRN) is an extension of stochastic Petri nets and provides compact modeling facilities for system analysis. In this paper, hierarchical SRN modeling techniques are used to overcome state largeness problem. The upper level model is used to compute availability and the lower level model captures the performance. And Normalized Throughput Loss (NTL) is obtained for the composite ring network for each node failures occurrence as a performability measure. One of the key contributions of this paper constitutes the Petri nets modeling techniques instead of complicate numerical analysis of Markov chains and easy way of performability analysis for a token ring network under SRN reward concepts.

Design Feature-Based Jetfighter Shape Modeling

  • Zang, Jing;Liu, Hu;Liu, Tianping;Ni, Xianping
    • International Journal of Aeronautical and Space Sciences
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    • v.14 no.3
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    • pp.222-228
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    • 2013
  • A jetfighter shape modeling method based on design features is researched, to improve the efficiency of shape modeling in the stage of conceptual aircraft design. The aircraft's general design features and shape parameters, including geometric and position parameters, are described. The coordinate systems of the entire aircraft and its components are defined. As a sample of local shape, a method of inlet intake modeling is introduced. The whole process of the modeling method is proposed. Three examples of different jetfighters are listed, to describe the achievement of basic layout, which includes four main elements. The Fusion of Components can be achieved by regulating the details of the sections of the fuselage. Sample Cases of typical layouts are shown to verify the effectiveness of the proposed method, which provides the basis for further analysis and optimization.

Scenario-based Goal-oriented Approach for Use Case Modeling (사용 사례 모델링을 위한 시나리오 기반의 목적 지향 접근법에 관한 연구)

  • Kim, Jeong-Wook;Park, Sooyong;Nam, Ki-Chan
    • Journal of the Korean Operations Research and Management Science Society
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    • v.28 no.2
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    • pp.91-103
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    • 2003
  • Use case modeling on UML (Unified Modeling Language) is getting widely used in OOAD and CBD and it is considered a useful technique in dealing with the complexity of the requirements analysis. However, some of the problems with use case modeling are that it is not structured, difficult to handle non-functional requirements, and to analyze impacts among use cases. To alleviate these problems, we propose a scenario-based goal-oriented approach for use case modeling. The proposed approach is to apply a goal-oriented analysis method to use case modeling. Since goal-oriented analysis method is not systematic and many heuristics are involved, we have adopted scenarios as the basis for goal extraction. The proposed method is applied to CBIS (City Bus Information Subsystem) in ITS (Intelligent Transportation System) domain. The proposed approach helps software engineers to analyze the impact among use cases and represent non-functional requirements.

A Study on Planning and Modeling System for Corporate Decision-Making (회사영업 및 경영의사결정지원을 위한 회사계획 및 모델화시스템에 관한 연구)

  • 이정록
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.8 no.12
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    • pp.49-63
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    • 1985
  • This paper is focused on the introduction of the types of models and explanation of the fundamental concepts and theory for development and use of the corporate planning and modeling system. Nowadays, a great deal of companies have been or experimenting with some form of a corporate planning and modeling system to support managerial and strategic decision making. From previous studies it was noted that most applications have tended to be financially based. This trend will probably continue. However, with the software and hardware currently available it is likely that companies will move more toward integrated models that link marketing, production, as will as financial areas. More emphasis will undoubtedly be placed on the use of econometric modeling, since this subelement of the overall planning and modeling process is closely tied to the market place and the economy. At any rate, wherever the development of corporate planning and modeling system is directed, clear understanding for the fundamental concepts and elements of the system is settled in advance in order to develope and use it.

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Game Theoretic Modeling for Mobile Malicious Node Detection Problem in Static Wireless Sensor Networks

  • Ho, Jun-Won
    • International Journal of Internet, Broadcasting and Communication
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    • v.13 no.1
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    • pp.238-242
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    • 2021
  • Game theory has been regarded as a useful theoretical tool for modeling the interactions between distinct entities and thus it has been harnessed in various research field. In particular, research attention has been shown to how to apply game theory to modeling the interactions between malign and benign entities in the field of wireless networks. Although various game theoretic modeling work have been proposed in the field of wireless networks, our proposed work is disparate to the existing work in the sense that we focus on mobile malign node detection problem in static wireless sensor networks. More specifically, we propose a Bayesian game theoretic modeling for mobile malign node detection problem in static wireless sensor networks. In our modeling, we formulate a two-player static Bayesian game with imperfect information such that player 1 is aware of the type of player 2, but player 2 is not aware of the type of player 1. We use four strategies in our static Bayesian game. We obtain Bayesian Nash Equilibria with pure strategies under certain conditions.

A Systematic Construction Process of 3D Database for Realtime Virtual Simulation of Transportation Equipments (수송장비의 실시간 가상 시뮬레이션을 위한 3차원 데이터베이스의 체계적인 구축 프로세스)

  • Kim, Bo-Hyun
    • IE interfaces
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    • v.16 no.2
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    • pp.258-267
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    • 2003
  • Recently, virtual reality technologies have been rapidly developed and realtime virtual simulation methods have been extensively employed for several application areas such as game, sports, manufacturing, military, and so on. A 3D database in realtime virtual simulation plays a key role because it makes users feel reality in virtual space. In a application view of 3D database, a systematic construction approach is required to reduce its construction time and increase its quality. However, many researches have been mostly focused on realtime graphic issues and its key technologies. In virtual simulation of transportation equipments, this paper proposes a systematic construction process of 3D database consisting of four stages as follows: 1) determine the activity space of a equipment, 2) collect data related to 3D database construction, 3) make a 3-dimensional modeling strategy, and 4) generate and evaluate a 3D model. This paper also introduces a new procedure of 3D environment modeling, which summarizes and expands our modeling experiences, to be used as a modeling guide.