• 한국군사과학기술학회지
• /
• 제9권4호
• /
• pp.61-70
• /
• 2006

This paper is to describe LYNX-ESM Simulation System to simulate for EW operating environment analysis and system performance verification of LYNX-ESM system using Discrete Event Simulation(DEVS) Methodology. This system consists of 3 PC with TCP/IP network. Each PC is loaded with Modeling & Simulation program based DEVS. Each connected program conducts EW simulation. As a result, we analyze the operating environment of the maritime EW threat, simulate the EW threat discrimination and geolocation capability, and estimate the LYNX-ESM system effectiveness before real LYNX-ESM system development.

• 한국해양공학회지
• /
• 제9권1호
• /
• pp.47-56
• /
• 1995

This study is aimed to have a database of system development for the prediction, monitoring, analyzing, and evaluation of tensile strength and damage characteristics through AE technique for CFRP. Therefore the correlations between impact characteristics (such as impact velocity, impact energy, delamination area etc) and AE signals for CFRP laminates were investigated. And also it were accomplished the evaluation of tensile strength and the investigation on correlation with AE signals for impact damaged specimen of CFRP laminates.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2001년도 춘계학술대회논문집
• /
• pp.836-842
• /
• 2001

The more sophisticated patterns of propagation model is presented in this paper, which includes three different source characteristics. The spherical, cosine and dipole radiation characteristics compared and sound event level and the maximum sound level are calculated by experiment and calculation. It is shown that patterns of propagation has dipole characteristics for low speed range(below about 150km/h) at electric multiple system. We know that push-pull high speed system(maximum speed: 300km/h) has cosine characteristics of noise propagation. For this purpose, We conduct the experiment of noise and know the empirical formula of noise level and radiation coefficient K. This model of simulation is conducted through point source array model at wheel/rail contact point by using program and experimental formula. We can guess prediction of profile, flat and wear of wheel by above modeling in near field.

• 한국시뮬레이션학회논문지
• /
• 제8권4호
• /
• pp.137-154
• /
• 1999

In this paper, we propose a software design method that will track the effects of modifications in a component to the rest of the components in the design phase. The prediction of the effects due to the design modifications before coding can be a valuable aid for the complex and large software development. Within the method, the target system is represented by the structured I/O system level specification which is one of the system representation level defined by the system theory. Then it is abstracted to the I/O system level. The DEVS (Discrete Event System Specification) model is constructed based on tile I/O system level specification. Finally, the DEVS model is simulated to generate the behavior of the software by the abstract simulator in DEVS simulation environment. As an application, the graphic user interface system of a metal grating production scheduling system is presented.

• 한국주거학회논문집
• /
• 제1권1호
• /
• pp.37-48
• /
• 1990

The objective of this study is to suggest a housing life cycle of Korean families which adds to the establishment of reasonable housing standards and to the prediction of fufure-oriented family housing behavior by reviewing published papers. Following model is suggested as a housing life cycle suitable to assess the family housing behavior in Korea. 1st stage : period of house searching 2nd stage : period of house changing 3rd stage : period of house stabilizing \circled1 size enlargement phase \circled2 quality improvement phase \circled3 stable settlement phase 4th siage : period of house contracting 5th stage : period of house depending Since the proposed model is hypothetical, it must be tested and modified by the extensive social survey research on the real housing event history.

• 한국건설관리학회논문집
• /
• 제6권1호
• /
• pp.73-79
• /
• 2005

This paper, introduces a Stochastic Project Scheduling Simulation system (SPSS III) developed by the author to predict a project completion probability in a certain time. The system integrates deterministic CPM, probabilistic PERT, and stochastic Discrete Event Simulation (DES) scheduling methods into one system. It implements automated statistical analysis methods for computing the minimum number of simulation runs, the significance of the difference between independent simulations, and the confidence interval for the mean project duration as well as sensitivity analysis method in What-if analyzer component. The SPSS 111 gives the several benefits to researchers in that it (1) complements PERT and Monte Carlo simulation by using stochastic activity durations via a web based JAVA simulation over the Internet, (2) provides a way to model a project network having different probability distribution functions, (3) implements statistical analyses method which enable to produce a reliable prediction of the probability of completing a project in a specified time, and (4) allows researchers to compare the outcome of CPM, PERT and DES under different variability or skewness in the activity duration data.

• 정보와 통신
• /
• 제31권3호
• /
• pp.103-116
• /
• 2014

This paper proposes the design of Vehicular Cyber-Physical Systems (called VCPS) based on vehicular cloud for smart road networks. Our VCPS realizes mobile cloud computing services where vehicles themselves or mobile devices (e.g., smartphones and tablets of drivers or passengers in vehicles) play a role of both cloud server and cloud client in the vehicular cloud. First, this paper describes the architecture of vehicular networks for VCPS and the delay modeling for the event prediction and data delivery, such as a mobile node's travel delay along its navigation path and the packet delivery delay in vehicular networks. Second, the paper explains two VCPS applications as smart road services for the driving efficiency and safety through the vehicular cloud, such as interactive navigation and pedestrian protection. Last, the paper discusses further research issues for VCPS for smart road networks.

• Corrosion Science and Technology
• /
• 제15권1호
• /
• pp.6-12
• /
• 2016

Flow-Accelerated Corrosion (FAC) is a well-known degradation mechanism that attacks the secondary piping in nuclear power plants. Since the Surry Unit 2 event in 1986, most nuclear power plants have implemented management programs to deal with damages in carbon and low-alloy steel piping. Despite the utmost efforts, damage induced by FAC still occurs in power plants around the world. In order to predict FAC wear, some computer programs were developed such as CHECWORKS, CICERO, and COMSY. Various data need to be input to these programs; the chemical composition of secondary piping, flow operating conditions and piping geometries. CHECWORKS, developed by the Electric Power Research Institute (EPRI), uses a geometry code to calculate geometry effects. Such a relatively simple geometry code is limited in acquiring the accuracy of FAC prediction. Recently, EPRI revisited the geometry code with the intention of updating it. In this study, numerical simulations were performed for two adjacent $90^{\circ}$ elbows and the results were analysed in terms of the proximity effect between the two adjacent elbows.

• 한국빅데이터학회지
• /
• 제3권1호
• /
• pp.47-54
• /
• 2018

비즈니스 프로세스 분석의 기존 연구들은 비즈니스 프로세스에 포함된 업무, 고객 서비스, 작업자 편의, 수행시간 예측 등 다양한 요소를 분석하였다. 이러한 요소를 정확히 분석하기 위해서는 정보시스템에 기록된 실제 이력 데이터를 활용하는 것이 효과적이다. 프로세스 마이닝은 이벤트 로그 데이터로부터 비즈니스 프로세스의 여러 가지 요소를 분석하는 기법이다. 본 사례 연구는 구매 대행 업체의 업무 수행 데이터에 프로세스 마이닝를 적용하여 구매 대행 프로세스의 업무 흐름, 수행 시간, 담당자 등의 프로세스 운영 분석을 수행하였다.

• 한국항공운항학회지
• /
• 제4권1호
• /
• pp.7-24
• /
• 1996

A methodology has been developed for predicting aircraft reliability incorporating both C.C.F.s(Common-Cause Failures), and phased missions. Failure behaviour of an aircraft, or it's systems are predicted. Both independent failures, and C.C.F.s, are modelled by the Markov process, and simulated using Monte Carlo sampling with the robust variance reduction method. Prediction of safety and reliability is made through discrete-event simulation of aircraft operations. A case study is described for investigating the safety and reliability of the propulsion system of two-, three- and four-engined aircraft. This is particularly important for the design of ETOPS(Extended Range of Two-Engined Aircraft Operations) and results are presented for the cases with, and without the effect of C.C.F.s.