• 제목/요약/키워드: Under-test

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저소음 Axle 개발을 위한 디플렉션 Test에 대한 연구 (Deflection Test for Low Noise Axle)

  • 최병재;박순관;이강현;조윤경;전성하
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 추계학술대회논문집
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    • pp.1391-1394
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    • 2007
  • In order for Hypoid gear development. Gears are required to sustain heavy loads or on applications where the gear box is made or a material with a different coefficient of thermal expansion form that or the gears and shafts, it is desirable to make a deflection and contact check under load. The deflection test is performed in the actual gear mounting using completely processed gear. This test should cover the full operating range of gear loads from no load to peak load. Under peak load the contact pattern should extend to the tooth boundaries without showing a concentration of the contact pattern at any point on the tooth surface.

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Testing Exponentiality of Kullback-Leibler Information Function based on a Step Stress Accelerated Life Test

  • 박병구;윤상철
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2000년도 추계학술발표회 논문집
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    • pp.235-240
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    • 2000
  • In this paper a test of fit for exponentiality and we propose the estimator of Kullback-Leibler Information functions using the data from accelerated life tests. This acceleration model is assumed to be a tampered random variable model. The procedure is applicable when the exponential parameter based on the data from accelerated life tests is or is not specified under null hypothesis. Using Simulations, the power of the proposed test based on use condition of accelerated life test under alternatives is compared with that of other standard tests in the small sample.

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A Kolmogorov-Smirnov-Type Test for Independence of Bivariate Failure Time Data Under Independent Censoring

  • Kim, Jingeum
    • Journal of the Korean Statistical Society
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    • 제28권4호
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    • pp.469-478
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    • 1999
  • We propose a Kolmogorov-Smirnov-type test for independence of paired failure times in the presence of independent censoring times. This independent censoring mechanism is often assumed in case-control studies. To do this end, we first introduce a process defined as the difference between the bivariate survival function estimator proposed by Wang and Wells (1997) and the product of the product-limit estimators (Kaplan and Meier (1958)) for the marginal survival functions. Then, we derive its asymptotic properties under the null hypothesis of independence. Finally, we assess the performance of the proposed test by simulations, and illustrate the proposed methodology with a dataset for remission times of 21 pairs of leukemia patients taken from Oakes(1982).

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확률계수 열화율 모형하에서 판정가속을 도입한 가속열화시험의 설계 (Design of Accelerated Degradation Test with Tightened Critical Values under Random Coefficient Degradation Rate Model)

  • 조유희;서순근
    • 대한산업공학회지
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    • 제34권1호
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    • pp.23-31
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    • 2008
  • This paper presents accelerated degradation test plans considering adoption of tightened critical values. Under arandom coefficient degradation rate and log-linear acceleration models, the asymptotic variance of an estimatorfor a lifetime quantile at the use condition as the optimization criterion is derived where the degradation ratefollows a lognormal and Reciprocal Weibull distributions, respectively and then the low stress level andproportions ofunits allocated to each stress level are determined. We also show that the developed test plans canbe applied to the multiplicative model with measurement error.

On Best Precedence Test when Data are subject to Unequal Patterns of Censorship

  • Kim, Tai-Kyoo;Park, Sang-Gue
    • 품질경영학회지
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    • 제22권1호
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    • pp.169-178
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    • 1994
  • Nonparametric tests for comparing two treatments when data are subject to unequal patterns of censorship are discussed. Best precedence test proposed by Slud can be viewed as a nice alternative test comparing with weighted log-rank tests, not to mention the advantage of short experimental period. This research revises some missing parts of Slud's test and examines the asymptotic power of it under the nonproportional hazard alternatives through the simulation. The simulation studies show best precedence test has reasonable power in the sense of robustness under nonproportional hazard alternatives and could be recommended at such situation.

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상전도식자기부상열차의 주행성능시험 및 평가 (Performance Test of the Urban Transit Maglev Vehicle(UTM-01) in Korea)

  • 조흥재;이종민
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1998년도 춘계학술대회논문집; 용평리조트 타워콘도, 21-22 May 1998
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    • pp.102-107
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    • 1998
  • UTM-01 is the first fall sized maglev test vehicle which is being developed by KIMM and Hyundai Precision and Industrial Co., since 1995. The vehicle employs normal conducting magnets for levitation and single sided linear induction motor for propulsion. The test vehicle has been under tests to assure its required performance since last May 1997. This paper reports various system level test results compared with simple 2 degree of freedom dynamic calculations. Test results include performance of the levitation and guidance system, propulsions system, and the dynamic behavior of the elevated guideway under the passage of the maglev vehicle.

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직류전원을 이용한 배전급 차단기의 등가 3상 합성투입시험법 (Equivalent three-phase synthetic making test for medium voltage circuit breaker of distribution system using DC power)

  • 박병락;조만영;김진석;신희상;김재철
    • 조명전기설비학회논문지
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    • 제25권7호
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    • pp.105-113
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    • 2011
  • The study about three-phase synthetic making test using DC power has been performed in order to increase the making test capacity on Vacuum Circuit Breaker. And, it made possible to solve the limitations that short-circuit testing facilities can not fulfill the testing requirements of VCB exceeding three-phase 36[kV] 31.5[kA]. By using DC power and high speed spark-gap switch, this method made the equivalence with the pre-arc that occurred during the making process under the fault condition of power system. As results, KERI(Korea Electrotechnology Research Institute) could have capacity to carry out type test for VCB under three-phase 52[kV] 40[kV], which satisfies the IEC Standard.

폴리머시멘트계 단면복구재의 내구성 및 철근부식특성에 관한 실험적 연구 (An Experimental Study on the Durability and Reinforcement Corrosion of Polymer Cement Based Repair Material)

  • 김영선;김영덕;나철성;조봉석;김규용;김무한
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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    • pp.487-490
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    • 2005
  • In this study, for the establishment of the performance evaluation methods and the quality control standards of durability recovery method, the data of indoor durability test and the data of the long term exposure test under the coast are accumulated and analyzed. As a result of the indoor test, durability of repair material was more superior to that of plain concrete, but as a result of investigating and evaluating exposure test at 30 month of exposure age under the coastal environment, the difference in electric potential and the reinforcement corrosion at place replaced with repair material are found.

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말뚝두부구속조건을 고려한 대구경 현장타설말뚝에 대한 수평정재하시험 연구 (A Study on Static Lateral Loading Test for Large Diameter Drilled Shaft Pile Considering the Pile Lead Fixity Conditions)

  • 이민희;황근배;정성민;최용규
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2004년도 춘계학술발표회
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    • pp.36-43
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    • 2004
  • Most of pile foundations are fixed head condition, but lateral loading test for pile is performed under free head condition generally In this study, a lateral loading test for a large diameter drilled shaft was performed under the fixed pile head and the free pile head condition, where lateral displacement along the pile depth was measure. Test results and theoretical values were compared and analyzed.

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풍하중에 의한 타원형 구조물의 진동 제어 (Vibration Control of Tower Structure under Wind Load)

  • 황재승;김윤석;주석준
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.427-430
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    • 2002
  • The present parer outlines the system identification and vibration control performance of air traffic control tower of Yangyang international airport with tuned mass damper(TMD). From the free vibration test, natural frequency, damping ratio and mode shape of tower are obtained and these values are compared with the values from numerical analysis. In the vibration control test to evaluate the vibration control performance, equivalent damping ratio increased by tuned mass damper are obtained in case the TMD is operated as passive mode. Damping ratio of tower evaluated from free vibration test is about $1.0{\%}$. It is very low value than damping ratio recommended in general code. Damping ratio of passive mode is about $5{\%}$. These equivalent damping ratio increased by TMD is enough to enhance the serviceability of tower structure under wind load.

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