• 제목/요약/키워드: mathematical model software

검색결과 200건 처리시간 0.028초

AMOS 소프트웨어에서 구현되는 구조방정식 모형과 의미 (A Mean of Structural equation modeling on AMOS Software)

  • 김경태
    • 한국조사연구학회:학술대회논문집
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    • 한국조사연구학회 2007년도 추계학술대회 발표논문집
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    • pp.55-65
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    • 2007
  • 연구에서는 공분산구조분석을 실시하기 위해 주로 사용하고 있는 AMOS 소프트웨어에 대하여 알아보려고 한다. 응용소프트웨어에서 활용된 수학적인 모형을 알지 못하면, 구조방정식에 대한 충분한 이해를 할 수 없으며, 구조방정식에 대한 8가지 가정이 어떻게 구현되는지 알 수 가 없다. 따라서 본 연구에서는 구조방정식모형 연구에서 주로 활용되었던 LISREL 프로그램으로 RAM과 MOSAN을 구현하였고 AMOS 결과와 비교분석하였다. 연구 결과에 따르면 AMOS프로그램은 8가지의 모든 가정을 따르지 않는 것으로 나타났다. AMOS 프로그램이 MOSAN보다는 RAM으로 구현되고 있음을 본 연구를 통해 알 수 있다. AMOS 소프트웨어 프로그램은 잠재변수(F)와 측정오차(e)간의 상관값을 산출할 때 충분히 추정을 하지 못하고 부분적으로만 추정하여 값을 산출하고 있음을 알 수 있었다.

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A Study on Development of LCD monitor-Based Pilots' Ship-Handling Simulator

  • Jeong, Tae-Gweon;Chen, Chao;Lee, Shin-Geol;Lee, Jeong-Jin;Huh, Yong-Bum
    • 한국항해항만학회지
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    • 제36권9호
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    • pp.715-720
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    • 2012
  • This paper is to introduce the development of a LCD monitor-based pilots' ship handling simulator installed in the office of Korea Maritime Pilots Association. This simulator is composed of hardware which includes working server array, operation PC, monitor array, rudder, thruster and telegraph peripheral devices, and software which includes ship mathematical model software, ship conning software, image supporting software and so on. In this simulator, MMG mathematical model is used to create thirteen(13) ship models, which are based on sea trial data & pilots' opinion. According to requirements of pilots, virtual scenes of different port areas are built, and some required additional functions are also developed. By using this simulator, pilots can fulfill all kinds of training exercises, design of channel approaching ports, traffic safety analysis, prevention of accident research and other tasks, so as to grasp the characteristics of different ships, and accumulate experience for piloting.

An Implementation of Web-based Stepwise Learning System for the Mathematical Problems

  • Kwon, Soon-Kak;Cho, Woo-Je;Kim, Tai-Suk
    • 한국멀티미디어학회논문지
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    • 제6권4호
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    • pp.630-637
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    • 2003
  • This study is designed to use the stepwise learning system for solving learner-oriented problem on the Web, which can help learners probe studying targets and contents of mathematics as well as search for a study-related materials. The study provides a Web-based Courseware design model based on the general multimedia systematic professor design model. It develops a program for remote lecture that can solve problems through interaction among a professor and the other learners. It also implements a remote teaming system for real-time environment of mathematical problems oriented by the learner. The system designed either as a Web-based mathematical Courseware or as a text mode has the purpose of providing a Web-based stepwise learning system for solving mathematical problems oriented by the learner.

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감소(減少)하는 고장률(故障率)하에서 오류예측 및 테스트 시간(時間)의 최적화(最適化)에 관한 연구(硏究) (Error Forecasting & Optimal Stopping Rule under Decreasing Failure Rate)

  • 최명호;윤덕균
    • 품질경영학회지
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    • 제17권2호
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    • pp.17-26
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    • 1989
  • This paper is concerned with forecasting the existing number of errors in the computer software and optimizing the stopping time of the software test based upon the forecasted number of errors. The most commonly used models have assessed software reliability under the assumption that the software failure late is proportional to the current fault content of the software but invariant to time since software faults are independents of others and equally likely to cause a failure during testing. In practice, it has been observed that in many situations, the failure rate decrease. Hence, this paper proposes a mathematical model to describe testing situations where the failure rate of software limearly decreases proportional to testing time. The least square method is used to estimate parameters of the mathematical model. A cost model to optimize the software testing time is also proposed. In this cost mode two cost factors are considered. The first cost is to test execution cost directly proportional to test time and the second cost is the failure cost incurred after delivery of the software to user. The failure cost is assumed to be proportional to the number of errors remained in the software at the test stopping time. The optimal stopping time is determined to minimize the total cost, which is the sum of test execution cast and the failure cost. A numerical example is solved to illustrate the proposed procedure.

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Performance Evaluation of Software Task Processing Based on Markovian Perfect Debugging Model

  • Lee, Chong-Hyung;Jang, Kyu-Beam;Park, Dong-Ho
    • 응용통계연구
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    • 제21권6호
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    • pp.997-1006
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    • 2008
  • This paper proposes a new model by combining an infinite-server queueing model for multi-task processing software system with a perfect debugging model based on Markov process with two types of faults suggested by Lee et al. (2001). We apply this model for module and integration testing in the testing process. Also, we compute several measure, such as the expected number of tasks whose processes can be completed and the task completion probability are investigated under the proposed model.

Modeling and Forecasting Saudi Stock Market Volatility Using Wavelet Methods

  • ALSHAMMARI, Tariq S.;ISMAIL, Mohd T.;AL-WADI, Sadam;SALEH, Mohammad H.;JABER, Jamil J.
    • The Journal of Asian Finance, Economics and Business
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    • 제7권11호
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    • pp.83-93
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    • 2020
  • This empirical research aims to modeling and improving the forecasting accuracy of the volatility pattern by employing the Saudi Arabia stock market (Tadawul)by studying daily closed price index data from October 2011 to December 2019 with a number of observations being 2048. In order to achieve significant results, this study employs many mathematical functions which are non-linear spectral model Maximum overlapping Discrete Wavelet Transform (MODWT) based on the best localized function (Bl14), autoregressive integrated moving average (ARIMA) model and generalized autoregressive conditional heteroskedasticity (GARCH) models. Therefore, the major findings of this study show that all the previous events during the mentioned period of time will be explained and a new forecasting model will be suggested by combining the best MODWT function (Bl14 function) and the fitted GARCH model. Therefore, the results show that the ability of MODWT in decomposition the stock market data, highlighting the significant events which have the most highly volatile data and improving the forecasting accuracy will be showed based on some mathematical criteria such as Mean Absolute Percentage Error (MAPE), Mean Absolute Scaled Error (MASE), Root Means Squared Error (RMSE), Akaike information criterion. These results will be implemented using MATLAB software and R- software.

A Stochastic Differential Equation Model for Software Reliability Assessment and Its Goodness-of-Fit

  • Shigeru Yamada;Akio Nishigaki;Kim, Mitsuhiro ura
    • International Journal of Reliability and Applications
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    • 제4권1호
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    • pp.1-12
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    • 2003
  • Many software reliability growth models (SRGM's) based on a nonhomogeneous Poisson process (NHPP) have been proposed by many researchers. Most of the SRGM's which have been proposed up to the present treat the event of software fault-detection in the testing and operational phases as a counting process. However, if the size of the software system is large, the number of software faults detected during the testing phase becomes large, and the change of the number of faults which are detected and removed through debugging activities becomes sufficiently small compared with the initial fault content at the beginning of the testing phase. Therefore, in such a situation, we can model the software fault-detection process as a stochastic process with a continuous state space. In this paper, we propose a new software reliability growth model describing the fault-detection process by applying a mathematical technique of stochastic differential equations of an Ito type. We also compare our model with the existing SRGM's in terms of goodness-of-fit for actual data sets.

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A Study on the Modelling and Control Method of an Anti - lock Brake System

  • Ki, Lim-Chul;Hoon, Song-Jeong;Suck, Boo-Kwang
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.112-112
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    • 2001
  • An Anti-lock Brake System ABS is developed to increase the stability of vehicle and to reduce the stopping distance when braking manoeuvres by measuring the wheel and vehicle speed. An ABS mathematical model which describes the dynamics of vehicle and calculate the stopping distance, is explained in this paper. To proceed this study, a mathematical model is produced with simulink software package. Although the model considered here is relatively simple, it retains the essential dynamics of the system. The results are evaluated at the various driving or road conditions. The results from mathematical model show that ABS reduces the stopping distance at the various road conditions. This mathematical model could be ...

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도상 다짐작업의 장기 일정계획 문제에 관한 수리적 모형 고찰 (A Study on a Mathematical Model of the Long-term Track Tamping Scheduling Problem)

  • 오석문;이지하;이희업;박범환;홍순흠
    • 한국철도학회논문집
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    • 제9권1호
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    • pp.50-56
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    • 2006
  • This paper presents a mathematical model of the long-term track tamping scheduling problem in the Korean highspeed railway system. The presented model encompasses various operational field constraints, moreover improves a state-of-the-art model in extending the feasible space. We show the model is sized up to intractable scale, then propose another approximation model that is possible to handle with the present computer system and commercial optimization package, directly. The aggregated index, lot, is selected, considering the resolution of the planning horizon as well as scheduling purpose. Lastly, this paper presents two test results for the approximation model. The results expose the approximation model to quite promising in deploying it into an operational software program for the long-term track tamping scheduling problem.

컴퓨터를 이용한 수학적 표현에 관한 연구 (A Study of the Mathematical Representation in using Computer)

  • 류희찬;조완영
    • 대한수학교육학회지:수학교육학연구
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    • 제8권2호
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    • pp.651-662
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    • 1998
  • Mathematics is means for making sense of one's experiential world and products of human activities. A usefulness of mathematics is derived from this features of mathematics. Keeping the meaning of situations during the mathematizing of situations. However, theories about the development of mathematical concepts have turned mainly to an understanding of invariants. The purpose of this study is to show the possibility of computer in representing situation and phenomena. First, we consider situated cognition theory for looking for the relation between various representation and situation in problem. The mathematical concepts or model involves situations, invariants, representations. Thus, we should involve the meaning of situations and translations among various representations in the process of mathematization. Second, we show how the process of computational mathematization can serve as window on relating situations and representations, among various representations. When using computer software such as ALGEBRA ANIMATION in mathematics classrooms, we identified two benifits First, computer software can reduce the cognitive burden for understanding the translation among various mathematical representations. Further, computer softwares is able to connect mathematical representations and concepts to directly situations or phenomena. We propose the case study for the effect of computer software on practical mathematics classrooms.

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