• Title/Summary/Keyword: test functions

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Mesh distortion sensitivity of 8-node plane elasticity elements based on parametric, metric, parametric-metric, and metric-parametric formulations

  • Rajendran, S.;Subramanian, S.
    • Structural Engineering and Mechanics
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    • v.17 no.6
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    • pp.767-788
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    • 2004
  • The classical 8-node isoparametric serendipity element uses parametric shape functions for both test and trial functions. Although this element performs well in general, it yields poor results under severe mesh distortions. The distortion sensitivity is caused by the lack of continuity and/or completeness of shape functions used for test and trial functions. A recent element using parametric and metric shape functions for constructing the test and trial functions exhibits distortion immunity. This paper discusses the choice of parametric or metric shape functions as the basis for test and/or trial functions, satisfaction of continuity and completeness requirements, and their connection to distortion sensitivity. Also, the performances of four types of elements, viz., parametric, metric, parametric-metric, and metric-parametric, are compared for distorted meshes, and their merits and demerits are discussed.

Neurocognitive Functions in Posttraumatic Stress Disorder (외상후 스트레스 장애 환자의 신경인지기능)

  • Kim, Sun-Kook;Lee, Kang-Joon;Lee, Seung-Hwan;Nam, Min;Chung, Young-Cho
    • Korean Journal of Biological Psychiatry
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    • v.10 no.2
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    • pp.147-158
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    • 2003
  • Objective:The differences of various neurocognitive functions, including attention, memory, motor function, and higher cognitive function were compared between PTSD patients and normal control subjects. Also, correlation with PTSD symptom severity and neurocognitive functions were evaluated between PTSD patients and normal control subjects. Method:We assessed the neurocognitive functions by computerized neurocognitive test(CNT) batteries. The visual continuous performance test(CPT) and digit span test, finger tapping test and Wisconsin card sorting test(WCST) were executed. The Impact of Event Scale-Revised(IES-R) was used in the evaluation of the severity of PTSD. Result:The PTSD patients showed significantly impaired neurocognitive performance in all of the items, compared with normal control subjects. The relation between impairment in neurocognitive functions and symptom severity showed significant correlations. Conclusion:These results imply that PTSD patients have impaired neurocognitive functions concerning with specific brain areas, especially the frontal area. For the thorough evaluation of further neurocognitive functions, more detailed evaluation items of neurocognitive functions and brain imaging studies are necessary in the future study.

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Simultaneous Tests with Combining Functions under Normality

  • Park, Hyo-Il
    • Communications for Statistical Applications and Methods
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    • v.22 no.6
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    • pp.639-646
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    • 2015
  • We propose simultaneous tests for mean and variance under the normality assumption. After formulating the null hypothesis and its alternative, we construct test statistics based on the individual p-values for the partial tests with combining functions and derive the null distributions for the combining functions. We then illustrate our procedure with industrial data and compare the efficiency among the combining functions with individual partial ones by obtaining empirical powers through a simulation study. A discussion then follows on the intersection-union test with a combining function and simultaneous confidence region as a simultaneous inference; in addition, we discuss weighted functions and applications to the statistical quality control. Finally we comment on nonparametric simultaneous tests.

Test bed for Advanced function of Smart Inverter and Results Based on Real-Time Simulation Platform (실시간 시뮬레이터 기반의 스마트 인버터 제어기능 시험 환경 구축 및 시험 결과)

  • Sim, Junbo;Ban, Minho;Lim, Hyeonok;Cho, Seong-Soo
    • KEPCO Journal on Electric Power and Energy
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    • v.7 no.1
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    • pp.107-114
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    • 2021
  • High penetration of renewable energy generators causes unnecessary investment for power system facilities. Especially with Korean government policies such as Renewable Energy 3020 and Inter-connection support Responsibility of KEPCO for 1 MW DERs, the applications of DER interconnection in distribution system have been increasing. To save the investment, smart control functions for DERs are required and the test bed for the inverters which have not been prepared are necessary to insure DER inter-connection stability. For this, test bed for advanced functions of a smart inverter has been constructed and the tests for necessary functions have been implemented. In this paper, the test bed and environment as well as specifications are introduced and the test results for the validation of the functions are analyzed.

Bayesian test for the differences of survival functions in multiple groups

  • Kim, Gwangsu
    • Communications for Statistical Applications and Methods
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    • v.24 no.2
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    • pp.115-127
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    • 2017
  • This paper proposes a Bayesian test for the equivalence of survival functions in multiple groups. Proposed Bayesian test use the model of Cox's regression with time-varying coefficients. B-spline expansions are used for the time-varying coefficients, and the proposed test use only the partial likelihood, which provides easier computations. Various simulations of the proposed test and typical tests such as log-rank and Fleming and Harrington tests were conducted. This result shows that the proposed test is consistent as data size increase. Specifically, the power of the proposed test is high despite the existence of crossing hazards. The proposed test is based on a Bayesian approach, which is more flexible when used in multiple tests. The proposed test can therefore perform various tests simultaneously. Real data analysis of Larynx Cancer Data was conducted to assess applicability.

A Study of the performance test method of DCS for a large industrial plant (분산제어시스템 기능점검 방법에 관한 연구)

  • Ma, B.R.;Lee, J.H.;Jung, M.S.
    • Proceedings of the KIEE Conference
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    • 1999.07b
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    • pp.883-886
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    • 1999
  • Recently, with the development of computer technology, field instrument and control system using in industrial fields have changed from mechanical, electrical systems to digital electronic systems. Distributed control system(DCS), control functions are dispersed for grading up reliability and informations are combined fur effective management has been developed and sold. As this system has been enlarged and complicated, it is difficult to testing the system and very important to verifing functions systematically. In this report, function test procedure which is performed spontaneously by domestic or foreign DCS manufacturer was searched and analyzed. As its results, the test procedure of DCS functions were proposed. The proposed procedure was applied to DCS being used for a thermal power plant. The function test for DCS requires continuous and dynamic input/output signals, therefore we proposed the method to compose virtual plant which simulate the DCS functions with. And we suggested the test procedure of each DCS function.

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The Difference of Hand Functions in Dominant Hand Types (우세손의 유형에 따른 손 기능 차이에 관한 연구)

  • Lee, Sun-Myung
    • Journal of Korean Clinical Health Science
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    • v.2 no.2
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    • pp.119-125
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    • 2014
  • Purpose. This study was conducted to prove the difference of dominant hand and non dominant hand in hand functions. Methods. We study difference of dominant hand and non dominant hand in hand functions that 40 university students participated in the study and performed a correlation between Jebsen-Taylor Hand Function test, O'conner Finger Dexterity test and Purdue Pegboard test. Results. In left dominant hand are functional of small common object, simulated feeding and large light object in Jebsen-Taylor Hand Function Test. Also O'conner Finger dexterity test are functional in left dominant hand and same result in Purdue pegboard test. Conclusion. The results of this study was left dominant hand is more functional than right dominant hand. So, we suggests that both hand using are improving of hand function in right dominant hand.

A comparison of the statistical methods for testing the equality of crossing survival functions (교차하는 두 생존함수의 동일성 검정법에 관한 비교연구)

  • Lee, Youn Ju;Lee, Jae Won
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.3
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    • pp.569-580
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    • 2015
  • Log-rank is widely used for testing equality of two survival functions, and this method is efficient only under the proportional hazard assumption. However, crossing survival functions are common in practice. Therefore, many approaches have been suggested to test equality of them. This study considered several methods; Renyi type test, modified Kolmogorov-Smirnov and Cramer-von Mises test, and weighted Log-rank test, which can be applied when the survival functions cross, and simulated power of those methods. Based on the simulation results, we provide the useful information to choose a suitable approach in a given situation.

A Design of Track Builder for Railway Signalling Test-bench (신호제어장치 시제품의 성능평가를 위한 현장에뮬레이션 모듈 설계)

  • Hwang, Jong-Gyu;Lee, Jong-Woo;Joung, Eui-Jin
    • Proceedings of the KIEE Conference
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    • 2001.04a
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    • pp.378-380
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    • 2001
  • The railway signaling system consists of computerized vital devices. Therefor it is important to validate the required functions of developed signaling system. To verify the condition and functions of signaling functions, the plentiful laboratory test is required. To achieve this, the emulation S/W for signaling test-bench is needed. The object-oriented concept for trackside signaling equipments emulation is described in this paper.

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DENSENESS OF TEST FUNCTIONS IN THE SPACE OF EXTENDED FOURIER HYPERFUNCTIONS

  • Kim, Kwang-Whoi
    • Bulletin of the Korean Mathematical Society
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    • v.41 no.4
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    • pp.785-803
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    • 2004
  • We research properties of analytic functions which are exponentially decreasing or increasing. Also we show that the space of test functions is dense in the space of extended Fourier hyper-functions, and that the Fourier transform of the space of extended Fourier hyperfunctions into itself is an isomorphism and Parseval's inequality holds.