• 제목/요약/키워드: limiting point

검색결과 193건 처리시간 0.027초

평활(平滑) 모수(母數) 선택(選擇)에 기준(基準)한 적합도(適合度) 검정(檢定) (Goodness-of-Fit Test Based on Smoothing Parameter Selection Criteria)

  • 김종태
    • Journal of the Korean Data and Information Science Society
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    • 제4권
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    • pp.137-146
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    • 1993
  • The Proposed goodness-of-fit test Statistic $\hat{\lambda}_{\alpha}$ derived from the test Statistc in Kim (1992) is itself a smoothing parameter which is selected to minimize an estimated MISE for a truncated series estimator, $d_{\hat{\lambda}{n}}$, of the comparison density function. Therefore, this test statistic leads immediately to a point estimate of the density function in the event that $H_{0}$ is ejected. The limiting distribution of $\hat{\lambda}_{\alpha}$ was obtained under the null hypothesis. It is also shown that this test is consistent against fixed alternatives.

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3차원 유동내에서 다양한 유동가시화 기술의 응용 (Application of various flow visualization techniques on complicated three-dimensional flows)

  • 정진택
    • 기계저널
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    • 제33권9호
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    • pp.803-810
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    • 1993
  • 벽면에서의 전단응력 분포와 유동장 내에서의 3차원 유동 요소를 추적하는 유동가시화 기법중 에서 몇 가지를 그 응용 예와 함께 살펴보았다. 3차원 유동의 주요 특징들과 한계유선(limiting streamlines)을 관찰하기 위해서는 oil and lampblack 기법이 충분하나 유속이 작거나 유동의 방향이 분명하지 않은 곳에서는 ink dot 기법을 적용하는 것이 좋다. Oil and lampblack 기법은 실험하고자 하는 유동의 조건에 따라 기름과 분말의 혼합비, 기름의 점도 등을 잘 선택하여야 한다. 안장점(Saddle point) 이나 재부착선(reattachment line)과 같이 성격상 중요한지점을 찾기 위해서는 털실 프로브(single tuft probe)가 유용하게 쓰이며, 이는 또 유동내에서 와동의 존재와 위치를 찾는데 쓰이기도 한다. 수치해석 결과 얻을 수 잇는 속도벡터와 같이 비교적 넓은 유동 장을 한눈에 관찰하기 위해서는 털실 격자망 (tuft grid)을 사용할 수 있으며 각 털실은 그 지 점세서의 유동의 방향과 그 안정성(steadiness)를 나타내준다. 이러한 유동가시화 방법들은 각 유동의 특성에 맞는 적절한 조건을 맞추기 위해서 많은 시행착오를 거쳐야 하며, 하나의 만족 스러운 결과를 얻기 위해서는 많은 기술과 시간과 연습을 요구하고 있어서 다른 정량적인 측정 기술과 더불어 커다란 노력과 관심을 기울여서 발전시켜야만 할 것이다.

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Weak Convergence of Processes Occurring in Statistical Mechanics

  • Jeon, Jong-Woo
    • Journal of the Korean Statistical Society
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    • 제12권1호
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    • pp.10-17
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    • 1983
  • Let $X^{(n)}_j, j=1,2,\cdots,n, n=1,2,\cdots$ be a triangular array of random variables which arise naturally in a study of ferromagnetism in statistical mechanics. This paper presents weak convergence of random function $W_n(t)$, an appropriately normalized partial sum process based on $S^{(n)}_n = X^{(n)}_i+\cdot+X^{(n)}_n$. The limiting process W(t) is shown to be Gaussian when weak dependence exists. At the critical point where the change form weak to strong dependence takes place, W(t) turns out to be non-Gaussian. Our results are direct extensions of work by Ellis and Newmam (1978). An example is considered and the relation of these results to critical phenomena is briefly explained.

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Comparison of Structural Change Tests in Linear Regression Models

  • Kim, Jae-Hee
    • 응용통계연구
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    • 제24권6호
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    • pp.1197-1211
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    • 2011
  • The actual power performance of historical structural change tests are compared under various alternatives. The tests of interest are F, CUSUM, MOSUM, Moving Estimates and empirical distribution function tests with both recursive and ordinary least-squares residuals. Our comparison of the structural tests involves limiting distributions under the hypothesis, the ability to detect the alternative hypotheses under one or double structural change, and smooth change in parameters. Even though no version is uniformly superior to the other, the knowledge about the properties of those tests and connections between these tests can be used in practical structural change tests and in further research on other change tests.

A JET EMERGING FROM A SLIT AT THE CORNER OF QUARTER PLANE

  • Wiryanto, L.H.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제13권4호
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    • pp.237-245
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    • 2009
  • A numerical solution is provided for a jet produced by a flow emerging from a slit at the bottom corner of a quarter plane. The flow is characterized by the Froude number F, based on the net volume flux and the width of the slit. We perform the free-surface flow for various values of F and another parameter corresponding to the position of the vertical wall. A jet with back-flow near the edge of the vertical wall is obtained, and the limiting case is a jet with a stagnation point.

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해양경찰의 과제와 발전 (Issues and Vision of Korea Maritime Police)

  • Sang-Jib Lee
    • 해양환경안전학회지
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    • 제6권2호
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    • pp.57-66
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    • 2000
  • The argument about enlarging or limiting the function of the Korea Maritime Police. Agency (KMPA) has been and will be repeated. In this paper, the author highlights the internal and external issues facing KMPA, stemming partly from deficiencies of its struggles for advancement of the organization and partly from shortcomings of political support far it. And he urges KMPA to change the organizational culture for maintaining its identity and characteristics as a lead maritime agency by practising a scientific management system for maximizing cost-effectiveness of its administrative resources. In addition, he also suggests that KMPA adopt the Total Quality Management System for quality improvements in services and greater efficiency in its organizational structure to meet the future competition in the changing political and legal environment. he concludes by providing a 6-point vision statement for KMPA from the standpoint of favoring enlarging the function of KMPA.

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Wireless Audio-visual Interface over UWB

  • Cui, Wei
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.1491-1494
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    • 2008
  • Typically internal mobile LCD display modules are connected to the mobile product baseband PCB with flexible printed circuit board equipped with board-to-board connector. This solution has a drawback of limiting the product concept work to certain solutions that are based on connector size, location, flexible PCB length, bending, etc. in the display module. Also flexible printed circuit board based solutions are not completely optimized from reliability point of view, causing flex circuit board breakings. For the external displays in the PC or Home entertainment market, the cable solution is too expensive and resource demanding. The wireless solution has obvious advantages over reliability, low cost and flexibility. This paper describes a wireless audio-visual interface solution.

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Research and Proposal on One Mile SART

  • Hayashi, Shogo;Ide, Manami;Ogawa, Masayasu;Yim, Jeong-Bin
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2004년도 Asia Navigation Conference
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    • pp.186-193
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    • 2004
  • As a point that should be improved further in present SART, the size, the number, and the economy were enumerated. Some SART developed to solve them in Japan were introduced in this paper. That is automatically operating SART, circular polarization SART and so on. In addition, One Mile SART was mentioned. It is SART miniaturized instead of limiting the function, because all crews and passengers can always carry the small and light SART. The parts were made for trial purposes and the performance was confirmed.

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Application of Near Infrared Spectroscopy (NIR) for Monitoring the Quality of Milk, Cheese, Meat and Fish - Review -

  • Ru, Y.J.;Glatz, P.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권7호
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    • pp.1017-1025
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    • 2000
  • The traditional methods for determining the quality of milk, cheese and meat are tedious and expensive, with a significant wastage of chemicals which pollute the environment. To overcome these disadvantages, the potential of near infrared spectrophotometry (NIR) for monitoring the quality of milk and meat has been evaluated by a number of researchers. While most studies indicate that NIR can be used to predict chemical composition of milk and meat, and to monitor the cutting-point during cheese manufacturing, one study demonstrated the potential of NIR to predict sensory characteristics (e.g. hardness and tenderness) of beef. These calibrations were developed on a small number of samples, limiting their value for adoption by the industries. Now that the sophisticated computer software is available, more robust calibrations need to be developed to monitor both chemical and physical characteristics of meat and meat products simultaneously.

Goodness-of-Fit Test Based on Smoothing Parameter Selection Criteria

  • Kim, Jong-Tae
    • Communications for Statistical Applications and Methods
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    • 제2권1호
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    • pp.122-136
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    • 1995
  • The objective of this research is to investigate the problem of goodness-of-fit testing based on nonparametric density estimation with a data-driven smoothing parameter. The small and large sample properties of a new test statistic $\hat{\lambda_a}$ is investigated. The test statistic $\hat{\lambda_a}$ is itself a smoothing parameter which is selected to minimize an estimated MISE for a truncated series estimator of the comparison density function. Therefore, this test statistic leads immediately to a point estimate of the density function th the event that $H_0$ is rejected. The limiting distribution of $\hat{\lambda_a}$ is obtained under the null hypothesis. It is also shown that this test is consistent against fixed alternatives.

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