• Computers and Concrete
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• 제33권6호
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• pp.725-738
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• 2024

This study presents a macro-modeling procedure for nonlinear finite element analysis of reinforced and prestressed concrete panels under blast loading. The analysis procedure treats cracked concrete as an orthotropic material based on a smeared rotating crack model within the context of total-load secant stiffness-based formulation. A direct time integration method compatible with the analysis formulation is adapted to solve the dynamic equation of motion. Considerations are made to account for strain rate effects. The analysis procedure is verified by modeling 14 blast tests from various sources reported in the literature including a blast simulation contest. The analysis results are compared against those obtained from experiments, simplified single-degree-of-freedom (SDOF) methods, and sophisticated hydrocodes. It is demonstrated that the smeared crack macro-modeling approach is a viable alternative analysis procedure that gives more information about the structural behavior than SDOF methods, but does not require detailed micro-modeling and extensive material characterization typically needed with hydrocodes.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2015년도 추계학술대회 논문집
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• pp.9-10
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• 2015

EI core inductor in power electronic circuit simulation is usually assumed as linear by using matrix model. However, nonlinear magnetic characteristics such as B-H characteristic are also important for the accurate simulation of the circuit behavior. To model nonlinear magnetic characteristics of EI core inductor with only DC bias table, this paper presents a method in PLECS simulation tool which is a commercially available simulation tool for power electronics circuit analysis. Comparing with ideal matrix model, the simplification and accuracy are improved by this modeling method. Also, compared to analysis by FEM, it is much simpler, faster and easier to simulate with power electronics circuit. Validation of the proposed model was verified by simulation and experiment results.

• 한국정보통신학회논문지
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• 제16권12호
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• pp.2581-2588
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• 2012

전투 시스템의 생존성은 전투 환경의 여러 요인에 따라 변화한다. 기존의 전투 시스템 생존성 분석 시뮬레이션 프로그램은 전투 환경에 따라 변화하는 생존성의 분석에는 한계를 가진다. 이 논문에서는 이러한 한계를 극복하기 위하여 에이전트 기반 모델링 및 시뮬레이션 기법을 이용한 전투 시스템의 동적 생존성 분석 방법을 제안한다. 시뮬레이션을 위해 DEVS 형식론, SES/MB 프레임워크, 에이전트 기술을 이용하여 전투 시스템을 구성하는 여러 요소를 모델링하고, 전투 시스템에 탑승하는 승무원을 각 역할에 따른 에이전트로 모델링한다. 제안하는 기법을 적용하면, 전투 환경에서의 전투 시스템 정적 생존성을 비롯하여 전투 시스템에 탑승하고 있는 승무원의 대응에 따라 변화하는 생존성을 분석할 수 있다.

• 한국항해항만학회지
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• 제44권6호
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• pp.469-476
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• 2020

해상교통 분야와 같이 선박, 항해사, 관제센터, 해운선사, 기상시스템, 지리정보시스템 등의 복잡하고 넓은 범위의 요구사항을 갖는 시스템의 모델링 및 시뮬레이션(Modeling and Simulation, M&S)을 위해서는 인간을 포함한 체계가 필요하다. 해상교통을 모의하기 위해서는 주요 요소인 항해사의 인적요인에 대한 모델링이 필요하다. 즉, 현실감 있는 해상교통 상황의 재현 및 예측을 위해 항해사의 행동양식, 항해전문성, 항해오류 등을 모델링하여 반영하는 것이 필요하다. 본 논문에서는 에이전트 기반의 해상교통 시뮬레이션을 위해서 항해사의 충돌회피를 위한 행동 분석을 수행하였으며, 기초 데이터의 확보를 위해 설문조사를 실시하였다. 설문조사를 통해 분석된 정보를 이용하여 선박 충돌상황에서 항해사의 행동과 유사한 에이전트 기반의 항해행동 모델을 개발하였으며, 해상교통분석 시뮬레이션 플랫폼의 개발을 위해 활용될 것이다.

• 드라이브 ㆍ 컨트롤
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• 제9권1호
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• pp.56-69
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• 2012

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1568-1570
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• 2005

The internet is already a part of life. It is very convenient and people can do almost everything with internet that should be done in real life. Along with the increase of the number of internet user, various network attacks through the internet have been increased as well. Also, Large-scale network attacks are a cause great concern for the computer security communication. These network attack becomes biggest threat could be down utility of network availability. Most of the techniques to detect and analyze abnormal traffic are statistic technique using mathematical modeling. It is difficult accurately to analyze abnormal traffic attack using mathematical modeling, but network simulation technique is possible to analyze and simulate under various network simulation environment with attack scenarios. This paper performs modeling and simulation under virtual network environment including $NGSS^{1}$ system to analyze abnormal traffic-flooding attack.

• 한국국방경영분석학회지
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• 제26권2호
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• pp.101-119
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• 2000

US DoD designated the High LEvel Architecture (HLA) as the standard technical architecture for all military simulation since 1996. HLA will supercede the current Distributed Interactive Simulation(DIS) and Aggregated LEvel Simulation Protocol(ALSP) methods by no funds for developing/modifying non-HLA compliant simulations. The new architecture specifies Rules which define relationships among federation components, an Objects Model Template which species the form which simulation elements are described, and an Interface Specification which describes the way simulations interact during operations. HLA is named as standard architecture in NATO, Australia and many other militaries. Also, it will be IEEE standard in the near future. It goes without saying that ROK military whose simulation models are almost from US must be prepared in areas such as ROK-US combined exercise, training, weapon system acquisition, interface models with C4I system, OPLAN analysis, operations, and os on. In this paper, we propose several effective alternatives and issues for ROK Defense Modeling and Simulation under the transition of new HLA architecture. Those include secure the kernel of new simulation technology and develop our own conceptual model, RTI software, prototype federation for each service and aggregated one. In order to challenge the new simulation architecture effectively, we should innovate our current defense modeling and simulation infrastructure such s manpower, organization, budget, research environment, relationships among academia and industry, and many others.

• 전기학회논문지P
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• 제63권2호
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• pp.74-80
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• 2014

Generator protection device has to detects an internal fault conditions in generator and abnormal operating conditions must be due to the hazards. Loss of excitation may cause generator itself failure as well as serious operating problem in power system, and then requires an appropriate response of generator protection device. Details modeling of generator control system and analysis of transient states in generator are important for optimal operation in power plants. In addition, the fault simulation data are also used for testing the characteristics of IED. In this paper, the hydro generator control system using PSCAD/EMTDC, visual simulation for power systems, was modeled. The generator control system which is composed of generator, turbine, exciter, governor was implemented. The parameters of generator control system model were obtained from field power plant. Loss of excitation simulations were performed while varying the fixed load. Several signals analysis were also performed so as to analyze transients phenomena.

• 한국컴퓨터정보학회논문지
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• 제21권12호
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• pp.107-114
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• 2016

Web system helps high-performance processing for big-data analysis and practical use to make various information using IT resources. The government have started the RPS system in 2012. The system invigorates the electricity production as using renewable energy equipment. The government operates system gathered big-data with various related information system data and the system users are distributed geographically. The companies have to fulfill the system, are available to purchase the REC to other electricity generation company sellers to procure REC for their duty volumes. The REC market operates single auction methods with users a competitive price. But the price have the large variation with various user trading strategy and sellers situations. This papler proposed RPS system modeling and simulation in web environment that is modeled in geographically distributed computing environment for web user with DEVS W/S. Web simulation system base on web service helps to analysis correlation and variables that act on trading price and volume within RPS big-data and the analysis can be forecast REC price.

• 한국자동차공학회논문집
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• 제19권2호
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• pp.57-65
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• 2011

In this paper, a hydropneumatic modeling and dynamic analysis of a heavy truck semi-active cabin air suspension system is presented. Semi-active cabin air suspension system improves driver's ride comfort by controlling the damping characteristics in accordance with driving situation. So it can reduce vibration between truck frame and cabin. Semi-active cabin air suspension system is consist of air spring, leveling valve and CDC shock absorber, and full cabin system are mathematically modelled using AMESim software. Simulation results of components and full cabin system are compared with experimental data of components and test results of a cabin using 6 axis simulation table. It is found that the simulation results are in good agreements with test results, and the hydropneumatic model can be used well to predict dynamic characterics of heavy truck semi-active cabin air suspension system.