• Title/Summary/Keyword: Modeling and simulation technique

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A study on mathematical modeling by neural networks (신경회로망을 이용한 수학적 모델에 관한 연구)

  • 이영진;이권순
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.624-627
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    • 1992
  • Mathematical modeling is majorly divided into three parts: the derivation of models, the fitting of models to data, and the simulation of data from models. This paper focuses on the parameter optimization which is necessary for the fitting of models to data. The method of simulated annealing(SA) is a technique that has recently attracted significant attention as suitable for optimization problem of very large scale. If the temperature is too high, then some of the structure created by the heuristic will be destroyed and unnecessary extra work will be done. If it is too low then solution is lost, similar to the case of a quenching cooling schedule in the SA phase. In this study, therfore, we propose a technique of determination of the starting temperature and cooling schedule for SA phase.

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Scale Modeling Technique for the Crash Analysis of Railway Vehicle Structure (철도차량 충돌 해석을 위한 축소모델링 기법 연구)

  • 김범진;허승진
    • Journal of the Korean Society for Railway
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    • v.5 no.4
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    • pp.231-236
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    • 2002
  • Todays, crash safety requirements of the railway vehicle structures become important design criterion according to the increased driving speed and the lightweight construction. Although the crash analysis using computer simulation can be effectively applied to predict the crash performance of the railway vehicles in the early design stage, the optimized design w.r.t the crash safety could be realized by the crash tests with actual prototype vehicles. However, it is very expensive and time-consuming task to perform the crash test of the railway vehicles. As a measure to cope with the problem, in this paper, the scale modeling technique is suggested and experimentally verified to predict the impact energy absorption characteristics of full scale model of aluminum extrusions sub-structures and the high-speed railway vehicle structure.

Photovoltaic System Operation Optimal Technique Considering Climate Condition and Residential Loads Pattern (기후조건 및 실부하패턴을 고려한 태양광 시스템 최적 운전기법)

  • Moon, Hee-Sung;Choe, Gyu-Yeong;Kim, Jong-Soo;Lee, Yeong-Guk;Lee, Byoung-Kuk
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.12
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    • pp.2385-2390
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    • 2009
  • Based on the detailed analysis of output characteristics of PV array and residential load usage pattern, a design method to calculate optimal battery capacity for stand-alone PV generation systems is proposed. And also, according to power flow Actual irradiation and temperature data are analyzed to compose a PV array simulator and also six representative home appliances are electrically modeled for load simulator, along with 24hours usage pattern. The surplus and insufficient power can be calculated from the proposed simulation platform, so that selection of an optimal battery capacity can be possible. The theoretical analysis and design process will be explained, along with informative simulation results.

Finite Element Simulation of Surface Wave Scattering (표면파 산란거동의 유한요소 해석)

  • 이종세;손윤기
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.04a
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    • pp.383-389
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    • 1998
  • A numerical study is conducted to examine the wave scattering at infilled trenches which may be constructed to reduce the ground-transmitted vibration. The finite element method is used for the simulation of the wave propagation in the semi-infinite region. In order to keep the computational burden manageable, the absorbing boundaries are employed. The numerical technique is validated by modeling a published problem. The results are shown to be in good agreement with the published data. The screening effectiveness of the infilled trenches is then studied for different trench dimensions and material properties.

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Analysis and Dynamic Modeling of a High-speed Tube Expander (고속 Tube Expander의 동적 모델링 및 해석)

  • 김재량;정원지;김수태;최욱환
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2003.10a
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    • pp.401-411
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    • 2003
  • Tube expanding process is for combining a heat-sink plate with hair-pins (Cu-tube) through plastic deformation. The two parts, i. e. , heat-sink plate and hair-pins are they components of a heat-exchanger for an air conditioner. This paper presents the analysis and dynamic modeling of a high-speed tube expander which integrates transfer of parts, fixing of parts, and tube expanding into one process. The 3-dimensional modeling of all the parts for the tube-expander was constructed using CATIA$\circledR$. then the CATIA$\circledR$ models are transferred into visuaINastran$\circledR$ to execute the 3-dimensional animation for checking prescribed cycle-time. The technique presented in this paper has been shown to be effective as a priori tool for verifying the design of a high-speed tube expander.

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Progressive collapse resistance of flat slabs: modeling post-punching behavior

  • Mirzaeia, Yaser;Sasani, Mehrdad
    • Computers and Concrete
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    • v.12 no.3
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    • pp.351-375
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    • 2013
  • Post-punching resistance of a flat slab can help redistribute the gravity loads and resist progressive collapse of a structure following initial damage. One important difficulty with accounting for the post-punching strength of a slab is the discontinuity that develops following punching shear. A numerical simulation technique is proposed here to model and evaluate post-punching resistance of flat slabs. It is demonstrated that the simulation results of punching shear and post-punching response of the model of a slab on a single column are in good agreement with corresponding experimental data. It is also shown that progressive collapse due to a column removal (explosion) can lead to punching failure over an adjacent column. Such failure can propagate throughout the structure leading to the progressive collapse of the structure. Through post-punching modeling of the slab and accounting for the associated discontinuity, it is also demonstrated that the presence of an adequate amount of integrity reinforcement can provide an alternative load path and help resist progressive collapse.

3D Contents Based Work Process Simulation Development (3D 콘텐츠 기반 작업 프로세스 시뮬레이션 개발)

  • Kim, Gui-Jung;Han, Jung-Soo
    • The Journal of the Korea Contents Association
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    • v.11 no.7
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    • pp.30-37
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    • 2011
  • In this paper we implemented 3D contents based work process simulation for 3D view contents. For this the method of 3D view technique is explained. The automobiles and PC assembly processes according to the virtual scenario showed the technique which assists workers through 3D view. Also for 3D information visualization, max script of contents modeling functions using 3D MAX was developed. The functions are designed to customize coordinate, material edit on modeling, rendering, and 3D object files with max script.

Mathematical Modeling for Calculating the Vertical Air Temperature Distribution in an Atrium Space (아트리움 공간의 수직공기온도분포 계산을 위한 수학모형의 작성)

  • 박종수;안병욱
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.6
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    • pp.533-542
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    • 2003
  • This study aims to propose a simplified mathematical model for calculating vertical air temperature distribution in a four-sided atrium. In the first stage of the mathematical modeling, the computer model combined zonal model and solar radiation model using Monte Carlo method and Ray tracing technique went through a computer simulation with architectural variables applied to a four-sided atrium in summer. In the next stage, Curve Expert, a computer program that gets the most suitable solution ac-cording to the least squares method, is used to analyze the results of the computer simulation and to derive the mathematical model. The accuracy of the mathematical model was evaluated through a comparison of calculation results from a mathematical model and computer simulation. In this validation step using the least square method, the R2 value of the Zones 1, 2 and 3 showed higher than 0.945. Zone 4 has an R2 value of 0.911, lower than the previous three zones. However the relative error was below 0.5%, which is considered very small.

The Study for Making of Landscape Simulation Model for Landscape Design Review (경관심의를 위한 경관시뮬레이션 모형 작성 기법에 관한 연구)

  • Lee, Dong-Hwa;Kim, Jae-Myung
    • Journal of KIBIM
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    • v.9 no.3
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    • pp.54-60
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    • 2019
  • After Landscape Act was enacted, as awareness of landscape has increased and the need of expanding targets of landscape design review and improving landscape examination in terms of quality, this study aims to describe a technique of creating three dimensional landscape simulation model which is used for landscape design review. For this, the author of this study conducted analysis in terms of function and use of programs and compatibility with programs to find a way of creating models with the most efficient and optimum process. For creation of landscape simulation models, initial creation is important but in case that changes occur by operator changing or discussing development plans, rapid correction and change are needed. Therefore, this study described how to build more accrurate and efficient simulation at initial review and how to create a landscape simulation model for rapid response to changed plans during reconsideration.

Equivalent Circuit Modeling Applying Rational Function Fitting (유리함수 근사를 이용한 등가회로 모델링)

  • Paek, Hyun;Ko, Jae-Hyung;Kim, Kun-Tae;Kim, Hyeong-Seok
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.8 no.1
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    • pp.1-5
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    • 2009
  • In this paper, we propose a method that applies Vector Fitting (VF) technique to the equivalent circuit model for RF passive components. These days wireless communication system is getting smaller and smaller. So EMI/EMC is an issue in RF. We can solve PI/SI (Power Integrity/Signal Integrity) that one of EMI/EMC problem apply IFFT for 3D EM simulation multiple with input signal. That is time consuming task. Therefore equivalent circuit model using RF passive component is important. VF schemes are implemented to obtain the rational functions. S parameters of the equivalent circuit model is compared to those of EM simulation in case of the microstrip line structure.

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