• Title/Summary/Keyword: Life testing

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A Study on Operating Software Development and Calibration of Multi-Axis Simulation (다축 시뮬레이터의 구동 소프트웨어 개발 및 보정에 관한 연구)

  • 정상화;류신호;신형성;김상석;김종태;박용래
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.141-141
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    • 2000
  • In the recent day, fatigue life prediction techniques play a major role in the design of components in th ground vehicle industry. Full scale durability testing in the laboratory is an essential of any fatigue life evaluation of components or structure of the automotive vehicle. Component testing is particularly important in today's highly competitive industries where the design to reduce weight and production costs must be balanced with the necessity to avoid expensive service failure. Generally, multi-axis durability testing simulator is used to car교 out the fatigue test. In this paper, the operation software for simultaneously driving 3-axis simulator is developed and the real-time signals of input-output data are displayed in window of PC. Moreover, the displacements and the loads of 3-axis actuators are calibrated separately and the operating characteristics of the actuators are evaluated.

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The Bibliographical Study Nuruk (누룩의 문헌고찰)

  • 이미경;이성우;윤태헌
    • Journal of the East Asian Society of Dietary Life
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    • v.4 no.1
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    • pp.19-29
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    • 1994
  • In this paper a review of literature on Nuruk(yeast) between 1907 and 1945 was made, which showed that barley, rice bran, oat, rye, and other ingredients were originally used according to region and production quantity. Yeast can be classified into rough (Chokuk) and powder (Bunkuk) types depending on the degree of grinding. Yeast also had seasonal names, being called " Choonkuk", Hakuk", Jeolkuk", and "Dongkuk" in the spring, summer, autumn and wither respectively. The form of yeast in terms of quantity, size, and shape varied greatly by region, Production facilities were composed of plant structures to suit each process, enabling continuous output. The production process included shaping, placement in the fermenting chamber, piling by turns, risk-sifting and final output. Testing procudures were divided into visual inspection, physical testing, and chemical analyses.

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Testing NRBU Class of Life Distributions Using a Goodness of Fit Approach

  • El-Arishy, S.M.;Diab, L.S.;Alim, N.A. Abdul
    • International Journal of Reliability and Applications
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    • v.7 no.2
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    • pp.141-153
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    • 2006
  • In this paper, we present the U-Statistic test for testing exponentiality against new renewal better than used (NRBU) based on a goodness of fit approach. Selected critical values are tabulated for sample sizes n=5(1)30(10)50. The asymptotic Pitman relative efficiency relative to (NRBU) test given in the work of Mahmoud et all (2003) is studied. The power estimates of this test for some commonly used life distributions in reliability are also calculated. Some of real examples are given to elucidate the use of the proposed test statistic in the reliability analysis. The problem in case of right censored data is also handled.

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Testing Harmonic Used Better than Aged in Expectation in Upper Tail(HUBAEUT) Class of Life Distributions Using Kernel Method

  • Abu-Youssef, S.E.;Al-nachawati, H.
    • International Journal of Reliability and Applications
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    • v.7 no.2
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    • pp.89-99
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    • 2006
  • A new classes of life distribution, namely harmonic used better than aged in expectation in upper tail (HUBAEUT) is introduced. Testing exponentiality against this class is investigated using kernel method. The limiting null and nonnull distribution of the test statistics is normal and the null variance is calculated exactly. Selected critical values are tabulated for sample sizes of 5(1)40. Power of the test are estimated by simulation. the efficacies of the test statistics used for testing against HUBAEUT are calculated for som common alternatives and are compared to some other procedures. It is shown that proposed test is simple, has high relative efficiency and power for some commonly used alternatives. The set of real data are used as an examples to elucidate the use of the proposed test statistics for practical reliability.

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Testing Whether New Is Better Than Used of Specified Age Using Moments Inequalities

  • Ahmad, Ibrahim A.;Al-Wasel, Ibrahim A.
    • International Journal of Reliability and Applications
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    • v.3 no.1
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    • pp.17-23
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    • 2002
  • The class of “new better than used of a specified age” is a large and practical class of life distributions. Its properties, applicability, and testing was discussed by Hollander, Park and Proschan (1986). Their test, while remaining the yardstick for this class, suffers from weak efficiency and weak power, especially for specified ages below the average age. Thus, it is beneficial to have an alternative testing procedure that would work better for early ages and still work well for later ages. This is exactly the subject of the current note. The test developed here is also simpler than that of Hollander, et. al. (1986).

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The Method of Determining Stress Levels Regarding the Electrical ALT through Optical Temperature Sensor

  • Ryu, Haeng-Soo;Han, Gyu-Hwan;Yoon, Nam-Sik
    • Journal of Electrical Engineering and Technology
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    • v.3 no.2
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    • pp.184-191
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    • 2008
  • Electrical endurance is the critical characteristic of Magnetic contactors(MCs), which are widely used in such power equipment as elevators, cranes, and factory control rooms in order to close and open control circuits. Testing time, however, is not short in typical cases in which some method of reducing the testing period is required. This study shows the method of determining the stress level of electrical ALT(Accelerated Life Test) through optical temperature sensor and the relationship between 0.05 s and 0.1 s for on-time. The tool used for analyzing the test result is MINITAB. I will propose the method of determining the optimized stress level through optical temperature sensor, which will contribute to minimize the testing time and development period and also raise the product reliability.

Preimplantation genetic testing for aneuploidy: The management of mosaic embryos

  • Yu, Eun Jeong;Kim, Min Jee;Park, Eun A;Kang, Inn Soo
    • Clinical and Experimental Reproductive Medicine
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    • v.49 no.3
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    • pp.159-167
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    • 2022
  • As the resolution and accuracy of diagnostic techniques for preimplantation genetic testing for aneuploidy (PGT-A) are improving, more mosaic embryos are being identified. Several studies have provided evidence that mosaic embryos have reproductive potential for implantation and healthy live birth. Notably, mosaic embryos with less than 50% aneuploidy have yielded a live birth rate similar to euploid embryos. This concept has led to a major shift in current PGT-A practice, but further evidence and theoretically relevant data are required. Proper guidelines for selecting mosaic embryos suitable for transfer will reduce the number of discarded embryos and increase the chances of successful embryo transfer. We present an updated review of clinical outcomes and practice recommendations for the transfer of mosaic embryos using PGT-A.

A study on the fault analysis of CMOS logic circuit using IDDQ testing technique (IDDQ 테스트 방식을 이용한 CMOS 논리회로의 고장분석에 관한 연구)

  • Han, Seok-Bung
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.9
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    • pp.1-9
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    • 1994
  • This paper analyzes the faults and their mechanism of CMOS ICs using IDDQ testing technique and evalutes the reliability of the chips that fail this test. It is implemented by the three testing phases, initial test, burn-in and life test. Each testing phase includes the parametric test, functional test, IDDQ test and propagation delay test. It is shown that the short faults such as gate-oxide short, bridging can be only detected by IDDQ testing technique and the number of test patterns for this test technique is very few. After first burn-in, the IDDQ of some test chips is decreased, which is increased in conventional studies and in subsequent burn-in, the IDDQ of all test chips is stabilized. It is verified that the resistive short faults exist in the test chips and it is deteriorated with time and causes the logic fault. Also, the new testing technique which can easily detect the rsistive short fault is proposed.

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Clinical Genetic Testing in Children with Kidney Disease

  • Kang, Eungu;Lee, Beom Hee
    • Childhood Kidney Diseases
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    • v.25 no.1
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    • pp.14-21
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    • 2021
  • Chronic kidney disease, the presence of structural and functional abnormalities in the kidneys, is associated with a lower quality of life and increased morbidity and mortality in children. Genetic etiologies account for a substantial proportion of pediatric chronic kidney disease. With recent advances in genetic testing techniques, an increasing number of genetic causes of kidney disease continue to be found. Genetic testing is recommended in children with steroid-resistant nephrotic syndrome, congenital malformations of the kidney and urinary tract, cystic disease, or kidney disease with extrarenal manifestations. Diagnostic yields differ according to the category of clinical diagnosis and the choice of test. Here, we review the characteristics of genetic testing modalities and the implications of genetic testing in clinical genetic diagnostics.