• Title/Summary/Keyword: modeling.

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Method of MBT Movement Modeling for Performance Analysis of SRMD System (근거리 미사일방어시스템 성능분석을 위한 전차 구동 모델링 기법)

  • Ha, Jong-Soo;Cho, Kyu-Gong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.2
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    • pp.173-180
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    • 2011
  • SRMD system which protects MBT from the threats in a short range is composed of 2 radars, 2 IRTs 1 CCU and 2 countermeasures. To analyze the performance of this system, there is a need to make the model of MBT on which this system is loaded. In this paper, a method of MBT movement modeling is proposed to fulfill the above need. The methods of the coordinate system transformation among the components and the modeling of a hull's traveling and a turret's turning are proposed. The method of the modeling of a pose variation caused by the vibrations is proposed and the results of the modeling are presented.

Modeling of HTS Resistive Superconducting Fault Current Limiter Using EMTDC (EMTDC를 이용한 고온초전도 저항형 한류기 모델링)

  • Lee, Jae-Deuk;Park, Min-Won;Yu, In-Keun
    • Proceedings of the KIEE Conference
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    • 2002.04a
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    • pp.216-218
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    • 2002
  • This study is the modeling of resistive type SFCLs. There was numerical modeling and simulation using EMTP in the conventional modeling of SFCL. The numerical modeling was presented an analysis of numerical characteristic of SFCL. And the modeling using EMTP was made up of the study for setting method of specific parameters of a SFCL. This paper proposes the model of resistive type superconducting fault current limiter using EMTDC(Electromagnetic transients for DC analysis program). The simulation schemes that can be applied to the utility network readily and cheaply under various conditions considering the sort of fault, the capacity of systems as well are strongly expected and emphasized among researchers.

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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.

A Survey of Applications of Artificial Intelligence Algorithms in Eco-environmental Modelling

  • Kim, Kang-Suk;Park, Joon-Hong
    • Environmental Engineering Research
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    • v.14 no.2
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    • pp.102-110
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    • 2009
  • Application of artificial intelligence (AI) approaches in eco-environmental modeling has gradually increased for the last decade. Comprehensive understanding and evaluation on the applicability of this approach to eco-environmental modeling are needed. In this study, we reviewed the previous studies that used AI-techniques in eco-environmental modeling. Decision Tree (DT) and Artificial Neural Network (ANN) were found to be major AI algorithms preferred by researchers in ecological and environmental modeling areas. When the effect of the size of training data on model prediction accuracy was explored using the data from the previous studies, the prediction accuracy and the size of training data showed nonlinear correlation, which was best-described by hyperbolic saturation function among the tested nonlinear functions including power and logarithmic functions. The hyperbolic saturation equations were proposed to be used as a guideline for optimizing the size of training data set, which is critically important in designing the field experiments required for training AI-based eco-environmental modeling.

WeblME: An Web-based Integrated Modeling Environment for Multi-facetted Model Representation and Management

  • Kim, Hyoung-Do;Kim, Jong-Woo;Park, Sung-Joo
    • Management Science and Financial Engineering
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    • v.5 no.1
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    • pp.27-49
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    • 1999
  • WebME is an Web-based integrated modeling environment that implements a multi-facetted modeling approach to mathematical model representation and management. Key features of WebME include the following: (i) sharing of modeling knowledge on the Web, (ii) a user-friendly interface for creating, maintaining, and solving models, (iii) independent management of mathematical models from conceptual models, (iv) object-oriented conceptual blackboard concept, (v) multi-facetted mathematical modeling modeling, and (vi) declarative representation of mathematical knowledge. This paper presents details of design and implementation issues that were encountered in the development of WebME.

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The Real -Time Dispersion Modeling System

  • Koo, Youn-Seo
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.E4
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    • pp.215-221
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    • 2002
  • The real-time modeling system, named AirWatch System, has been developed to evaluate the environmental impact from a large source. It consists of stack TMS (TeleMetering System) that measures the emission data from the source, AWS (Automatic Weather Station) that monitors the weather data and computer system with the dispersion modeling software. The modeling theories used in the system are Gaussian plume and puff models. The Gaussian plume model is used for the dispersion in the simple terrain with a point meteorological data while the puff model is for the dispersion in complex terrain with three dimensional wind fields. The AirWatch System predicts the impact of the emitted pollutants from the large source on the near-by environment on the real -time base and the alarm is issued to control the emission rate if the calculated concentrations exceed the modeling significance level.

An Analysis of the Characteristics of the High Speed Electromagnetic Valve (고속 전자 밸브의 특성 해석)

  • 송창섭
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1995.03a
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    • pp.34-39
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    • 1995
  • To reduce the shock in shifting the clutches and the brakes in automatic transmission have to be connected smoothly and disconnected rapidly. It is PCSV(Pressure Control Solenoid Valve) that play this role of automatic transmission. In this paper there were two steps in the analysis of the PCSV. The first step was modeling the elctromagnet by the permeance method. The second step was modeling the hydraulic circuit by the pressure differential equation. In addition to this modeling a experiment was performed and the commercial package program was used in order to justify modeling. The result of modeling coincide with the result of experiment and commercial package program. As a result this modeling is usable in analysis of dynamic characteractic of the PCSV.

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A Study on the Configuration Modeling and Aerodynamic Analysis of Small Airplanes for Flight Training (교육용 소형 항공기의 형상 모델링과 공력 분석에 관한 연구)

  • Cho, Hwankee
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.28 no.1
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    • pp.59-65
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    • 2020
  • This paper presents comparative results of configuration modeling and aerodynamic analysis to single-engine airplanes such as C-172, SR-20, and DA40NG. The software OpenVSP was used as an airplane configuration modeling tool. OpenVSP can provide the fastest method to get three-dimensional aircraft configuration from given basic data and drawings of aircraft. Parametric design input in OpenVSP, from given aircraft geometric parameters, was applied to small airplanes mentioned. New aircraft models in this study were reversely designed to coincide with the publicly obtained dimensions of the original aircraft. The basic aerodynamic analysis of newly designed modeling aircraft was performed by the vortex lattice method. Results are shown that the similarity of aerodynamic data obtained except for the lack of DA40NG. In conclusion, the modeling process applied to this work is valuable to obtain conceptual design insight in the reverse design from the small airplanes currently in use for flight training.

Development of a Multibody Dynamics Program Using the Object-Oriented Modeling

  • Han, Hyung-Suk
    • International Journal of Precision Engineering and Manufacturing
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    • v.4 no.6
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    • pp.61-70
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    • 2003
  • A multibody system dynamics analysis program is presented using one of the most useful programming methodologies, the object-oriented modeling, The object-oriented modeling defines a problem from the physical world as an abstract object. The object becomes encapsulated with the data and method, Analysis is performed using the object's interface, It is then possible for the user and the developer to modify and upgrade the program without having particular knowledge of the analysis program, The method presented in this paper has several advantages, Since the mechanical components of the multi-body system are converted into the class, the modification, exchange, distribution and reuse of classes are increased. It becomes easier to employ a new analysis method and interface with other S/W and H/W systems, Information can be communicated to each object through messaging. This makes the modeling of new classes easier using the inheritance, When developing a S/W for the computer simulation of a physical system, it is reasonable to use object-oriented modeling.

Sensor Modeling of KOMPSAT-2 Satellite Using Strip Image (스트립 영상을 이용한 KOMPSAT-2 위성 센서모델링)

  • Kim, Sang-Pil;Son, Hong-Gyu;Jo, Gyeong-Hun;Choi, Kang-Jo;Yoo, Son-Han
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2010.04a
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    • pp.217-219
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    • 2010
  • Sensor modeling is the basic step to extract and to use the information from satellite images. Sensor modeling requires ground control points. If we use a single image, we have limitations on modeling about images captured from regions that we can not approach or take GCPs. In this research, we use strip images to do sensor modeling by two methods. At first, we apply sensor modeiling to single image and apply the results by extrapolation. Next, we consider strip images to single image. As a result, we find the second method is more accurate about whole image.

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