• Title/Summary/Keyword: 단조 감소

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Detection of Target using Distributed Multi-Sonar System (다중 분산 소나 시스템을 이용한 표적 탐지)

  • 박치현;이재욱;고한석
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.635-638
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    • 2001
  • 본 논문에서는 수중 환경에서 분산 소나 시스템의 최적 정보 융합에 관한 알고리즘을 제시하였다. 기존의 방법은 Bayesian 법칙을 이용하여 local 소나와 퓨전 센터의 문턱치를 적절히 조절하여 분산 소나 시스템을 최적화했다. 그러나, 이러한 최적화 과정에서 소나의 개수를 늘려감에 따라 P/sub F/(false alarm probability)가 단조 증가하는 현상이 발생하였고 이러한 단점을 보완하기 위해 P/sub F/를 작은 간에 제한시키고 Bayesian 법칙과 Neyman-Pearson 법칙을 함께 적용하여 분산 소나 시스템을 최적화시킨다. 그러나, 이러한 조건 하에 시스템을 최적화시키는 것은 N-P hard 문제에 의해 계산 부하가 매우 크므로 unate 함수와 SQP(Sequential Quadratic Programming)을 이용하여 계산 부하를 감소시켰다.

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Hydrostatic pressure in the center of wire drawing and extrusion of viscoplastic material (점소성 재료의 인발과 변형역 중심에서의 정수압에 관한 연구)

  • Oh, Hung Kuk
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.5 no.3
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    • pp.170-177
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    • 1981
  • 1,200.deg.C에서의 단조철은 점소성을 나타내며 인발과 압출시 변형영역이 구형수렴형태가 됨을 실험을 통하여 나타난다. 이 변형역 모델로부터 평형방정식을 사용하여 평균 압출 및 인발응력과 정수압을 계산해 낸다. 평균 압출 및 임발응력은 상계 해석 방법에 의한 결과와 비교하여 본 연구의 해석방법의 유효성을 타진하고 정수압은 다른 연구자들의 결과와 비교 검토되며 특히 냉간가공의 경우와 비교 검토 된다. 그 외에 마찰계수, 급형각도와 단면감소율의 영향에 대해서도 논의 된다.

Function Regression algorithm (함수모형 회귀분석 및 알고리즘)

  • Kim, Seok Jun;Jang, Geun Ho;Kim, Ye Ji
    • Proceedings of the Korea Information Processing Society Conference
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    • 2017.11a
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    • pp.770-773
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    • 2017
  • Linear Regression 문제를 토대로 변형하여 선형회귀분석, 2차함수모형 회귀분석, '단조 증가(감소)' 3차 함수 모형 회귀분석과 그에 따라 변형되는 gradient descent 알고리즘을 기술한다.

The Study for Comparative Analysis of Software Failure Time Using EWMA Control Chart (지수 가중 이동 평균 관리도를 이용한 소프트웨어 고장 시간 비교분석에 관한 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • Convergence Security Journal
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    • v.8 no.3
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    • pp.33-39
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    • 2008
  • Software failure time presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing. For data analysis of software reliability model, data scale tools of trend analysis are developed. The methods of trend analysis are arithmetic mean test and Laplace trend test. Trend analysis only offer information of outline content. In this paper, we discuss exponentially weighted moving average chart, in measuring failure time. In control, exponentially weighted moving average chart's uses are efficiency case of analysis with knowing information, Using real software failure time, we are proposed to use exponentially weighted moving average chart and comparative analysis of software failure time.

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Analysis of Software Reliability Growth Model with Gamma Family Distribution (감마족 분포를 이용한 소프트웨어 신뢰 성장 모형의 분석)

  • Kan, Kwang-Hyun;Jang, Byeong-Ok;Kim, Hee-Cheul
    • Journal of IKEEE
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    • v.9 no.2 s.17
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    • pp.143-151
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    • 2005
  • Finite failure NHPP models proposed in the literature exhibit is either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. For the sake of proposing shape parameter of the Gamma family distribution, used the special pattern. Data set, where the underlying failure process could not be adequately described by the knowing models, which motivated the development of the Gamma or Weibull model and Gompertz model. Analysis of failure data set that led us to the Gamma or Weibull model and Gompertz model using arithmetic and Laplace trend tests, bias tests was presented in this Paper.

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A study on the Structure and Transformation Rate of Heat Treatment of Forged TAP Housing and Valve for Automotive Parts (단조용 자동차 부품 T/P Housing과 Valve의 열처리에 따른 조직 및 변형 속도에 관하여)

  • 유형종;이호진;이건영;최진일
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.4 no.3
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    • pp.155-158
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    • 2003
  • The effects of Mn, V addition on the behavior of structure and the effects of cooling rate of S20C steel for use of Tn housing and valve for automotive parts have been investigated. Transformation start temperature measured from inflection point of cooling curves has been found out to decrease with increasing cooling rate and to be more sensitive to Mn contents when cooling rate is fast. It was therefore shown that the grain was refined. If there is a big compacting pressure, it is indicated that hardness becomes much greater at surface than inside.

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The Comparative Study for ENHPP Software Reliability Growth Model based on Modified Coverage Function (변형 커버리지 함수를 고려한 ENHPP 소프트웨어 신뢰성장 모형에 관한 비교 연구)

  • Kim, Hee-Cheul;Kim, Pyong-Koo
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.6
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    • pp.89-96
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    • 2007
  • Finite failure NHPP models presented in the literature exhibit either constant. monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times. and estimation of the reliability and availability of a software product require quality of a critical element of the software testing process : test coverage. This model called Enhanced non-homogeneous Poission process(ENHPP). In this paper, exponential coverage and S-type model was reviewed, proposes modified(the superosition and mixture) model, which make out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method. model selection based on SSE statistics for the sake of efficient model, was employed.

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The Study for NHPP Software Reliability Growth Model Based on Hyper-exponential Distribution (초지수분포(Hyper-exponential)를 이용한 소프트웨어 신뢰성장 모형에 관한 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • Convergence Security Journal
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    • v.7 no.1
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    • pp.45-53
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    • 2007
  • Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, Goel-Okumoto and Yamada-Ohba-Osaki model was reviewed, proposes the hyper-exponential distribution reliability model, which maked out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method. For model determination and selection, explored goodness of fit (the error sum of squares). The methodology developed in this paper is exemplified with a software reliability random data set introduced by of Weibull distribution (shape 0.1 & scale 1) of Minitab (version 14) statistical package.

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A Study of Infinite Failure NHPP Software Reliability Growth Model base on Record Value Statistics with Gamma Family of Lifetime Distribution (수명분포가 감마족인 기록값 통계량에 기초한 무한고장 NHPP 소프트웨어 신뢰성장 모형에 관한 비교 연구)

  • Kim, Hee-Cheul;Sin, Hyun-Cheul
    • Convergence Security Journal
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    • v.6 no.3
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    • pp.145-153
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    • 2006
  • Infinite failure NHPP models for a record value satisfies mode proposed in the literature exhibit either monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, propose comparative study of software reliability model using Erlang distribution, Rayleigh and Gumbel distribution. Equations to estimate the parameters using maximum likelihood estimation of infinite failure NHPP model based on failure data collected in the form of interfailure times are developed. For the sake of proposing distribution, we used to the special pattern. Analysis of failure data set using arithmetic and Laplace trend tests, goodness-of-fit test, bias tests is presented.

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The Study for ENHPP Software Reliability Growth Model based on Superposition Coverage Function (중첩커버리지 함수를 고려한 ENHPP 소프트웨어 신뢰성장 모형에 관한 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • Convergence Security Journal
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    • v.7 no.3
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    • pp.7-13
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    • 2007
  • Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. Accurate predictions of software release times, and estimation of the reliability and availability of a software product require quantification of a critical element of the software testing process : test coverage. This model called Enhanced non-homogeneous poission process (ENHPP). In this paper, exponential coverage and S-shaped model was reviewed, proposes the superposition model, which maked out efficiency application for software reliability. Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE statistics for the sake of efficient model, was employed.

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