• Journal of Applied Reliability
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• v.14 no.1
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• pp.53-57
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• 2014

In the fields of reliability application, the most commonly used test methods for reliability demonstration are zero-failure acceptance tests since they require fewer test samples and less test time compared to other test methods that guarantee the same reliability with a given confidence level. For products with lognormal lifetime distribution, the value of scale parameter is usually assumed to be known in designing reliability demonstration tests. It is important to select correct values of scale parameters to guarantee the specified reliability with given confidence level exactly. The effect of using wrong values of scale parameters in designing reliability demonstration test for products with lognormal lifetime distribution is examined and selecting proper values of scale parameters for conservative reliability demonstration is discussed.

• Journal of Applied Reliability
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• v.14 no.4
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• pp.220-224
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• 2014

A Bayesian zero-failure reliability demonstration test method for products with Weibull lifetime distribution is presented. Inverted gamma prior distribution for the scale parameter of the Weibull distribution is used to design the Bayesian test plan and selecting a prior distribution using a prior test information is discussed. A test procedure with zero-failure acceptance criterion is developed that guarantee specified reliability of a product with given confidence level. An example is provided to illustrate the use of the developed Bayesian reliability demonstration test method.

• Journal of Applied Reliability
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• v.13 no.1
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• pp.1-10
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• 2013

A Bayesian zero-failure reliability demonstration test method for products with exponential lifetime distribution is presented. Beta prior distribution for reliability of a product is used to design the Bayesian test plan and selecting a prior distribution using a prior test information is discussed. A test procedure with zero-failure acceptance criterion is developed that guarantees specified reliability of a product with given confidence level. An example is provided to illustrate the use of the developed Bayesian reliability demonstration test method.

• Journal of Applied Reliability
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• v.11 no.3
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• pp.225-234
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• 2011

In the fields of reliability application, the most commonly used test methods for reliability qualification are zero-failure acceptance tests since they require fewer test samples and less test time compared to other test methods that guarantee the same reliability with a given confidence level. Usually values of shape parameters are assumed to be known in designing reliability qualification tests for Weibull lifetime distribution. It is important to select correct values of shape parameters to guarantee the specified reliability with given confidence level exactly. The effect of using wrong values of shape parameters in designing reliability qualification test for products with Weibull lifetime distribution is examined and selecting proper values of shape parameters for conservative reliability qualification is discussed.

• Korean Journal of Human Ecology
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• v.18 no.2
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• pp.465-476
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• 2009

The purpose of this study is to investigate recognition degree and acceptability of fashion trends of new consumers who live in digital era, and to determine how these factors have influence on their use of fashion trend information. The study was conducted with 696 people from 15 to 34 years old. A self-administrated questionnaire based on the results of previous researches was developed. The data were analyzed with statistical analyses such as frequency analysis, mean, factor analysis, t-test, ANOVA, correlation and regression analysis. The results are as follows: first, new digital consumer's recognition degree (RD) of fashion trends is 7.85 on the average, given that the top of scale is 20.0, it is quite low. Of fashion trend RD, fashion item RD is the highest. The female subjects recognize fashion trends better than the male subjects. Second, fashion trend acceptance of new digital generation is classified into 5 factors: 'search acceptance', 'lead acceptance', 'follow acceptance', 'non-acceptance', and 'delay acceptance'. The female subjects show higher degree in the factors of 'search acceptance', 'lead acceptance' and 'follow acceptance' of fashion trend than the males; hence it means that the females have more positive attitudes in fashion trend acceptance than the males. Third, there are significant differences between genders in the fashion information utilization. Compared to the males, the females more use fashion information on style, fabrics and color. Concludingly, their fashion trend recognition degree and acceptance made an influence in part on their utilization of fashion information.

• Progress in Medical Physics
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• v.29 no.4
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• pp.123-136
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• 2018

The complex dose distribution and dose transfer characteristics of intensity-modulated radiotherapy increase the importance of precise beam data measurement and review in the acceptance inspection and preparation stages. In this study, we propose a process map for the introduction and installation of high-precision radiotherapy devices and present items and guidelines for risk management at the acceptance test procedure (ATP) and commissioning stages. Based on the ATP of the Varian and Elekta linear accelerators, the ATP items were checked step by step and compared with the quality assurance (QA) test items of the AAPM TG-142 described for the medical accelerator QA. Based on the commissioning procedure, dose quality control protocol, and mechanical quality control protocol presented at international conferences, step-by-step check items and commissioning guidelines were derived. The risk management items at each stage were (1) 21 ionization chamber performance test items and 9 electrometer, cable, and connector inspection items related to the dosimetry system; (2) 34 mechanical and dose-checking items during ATP, 22 multileaf collimator (MLC) items, and 36 imaging system items; and (3) 28 items in the measurement preparation stage and 32 items in the measurement stage after commissioning. Because the items presented in these guidelines are limited in terms of special treatment, items and practitioners can be modified to reflect the clinical needs of the institution. During the system installation, it is recommended that at least two clinically qualified medical physicists (CQMP) perform a double check in compliance with the two-person rule. We expect that this result will be useful as a radiation safety management tool that can prevent radiation accidents at each stage during the introduction of radiotherapy and the system installation process.

• Journal of Advanced Navigation Technology
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• v.27 no.6
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• pp.782-787
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• 2023

Korea augmentation satellite system (KASS) integration, verification, qualification (IVQ) activity is verification of requirements for KASS system and its sub-system that were performed based on the inspection, analysis, review of design, test (IART) method from factory acceptance test (FAT) to test readiness review (TRR) after critical design review (CDR) was closed. In the FAT phase, developed equipment was installed on the test platform and we were verified interfaces between sub-systems and coupling test with the kass control station (KCS). In the site aceeptance test (SAT) phase, on-site verification was conducted by installing equipment verified by FAT such as kass reference station (KRS), kass processing station (KPS), kass uplink station (KUS), KCS. However, considering the developed plan and status, SAT was divided into 3 phases and coupling test was performed. In the TRR phase, the KASS system verification was performed through FAT's test list and additional test list using the satellite based augmentation system (SBAS) broadcast signal from geostationary earth orbit (GEO) 1.

• Journal of Korean Institute of Industrial Engineers
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• v.33 no.1
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• pp.76-85
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• 2007

A reliability acceptance sampling plan (RASP) consists of a set of life test procedures and rules for eitheraccepting or rejecting a collection of items based on the sampled lifetime data. Most of the existing RASPs areconcerned with the case where test items are available at the same time. However, as in the early stage ofproduct development, it may be difficult to secure test items at the same time. In such a case, it is inevitable toconduct a life test using sequentially supplied samples.In this paper, it is assumed that test items are sequentially supplied, the lifetimes of test items follow anexponential disthbution, failures are monitored continuously, arrival times of test items are known, and thenumber of test items at each arrival time is given. Under these assumptions, RASPs are developed by deter-mining the test completion time and the critical value for the maximum likelihood estimator of the mean lifetimesuch that the producer and consumer risks are satisfied. Then, the developed plans are compared to thetraditional Type-I censored RASPs in terms of the test completion time. Computational results indicate that thetest completion time of the developed RASP is shorter than that of the traditional Type-I censored plan in mostcases considered. It is also found that the superiority of the developed RASP becomes more prominent as theinter-arrival times of test items increase and/or the total number of test items gets larger.

• The Korean Journal of Community Living Science
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• v.27 no.2
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• pp.185-197
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• 2016

This study was conducted to examine the factors affecting the life satisfaction of married female immigrants and Korean husbands. Data for this study were obtained from the National Survey of Multicultural Families conducted in 2012. The study sample consisted of 5,232 couples within the first five years of marriage. Data were evaluated using a paired t-test, K-mean cluster analysis, ANOVA, and ordered logistic regression analysis. The results were as follows: 1) life satisfaction was higher for married female immigrants than for Korean husbands. 2) The general characteristics, acceptance attitude, language acceptance, and social network differed significantly depending on life satisfaction levels. 3) The multicultural acceptance attitude of husbands, ability of married female immigrants to speak Korean, and ability of Korean husbands to speak wives' native languages improved life satisfaction levels. The results of this study can be used to improve the life satisfaction of married female immigrants and Korean husbands.

• Journal of the Korean Home Economics Association
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• v.47 no.4
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• pp.99-110
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• 2009

The Technology Acceptance Model(TAM) proposed by Davis(1989) has been applied as a reliable and robust model in the study of user’s adoption of different technologies. However it is necessary to incorporate additional constructs to the original model in the quest for increased predictive power. This study investigate consumer’s acceptance of smart clothing applied by the extended TAM. Besides perceived ease of use and perceived usefulness, clothing involvement is included in the extended TAM. Data were collected from the adults over 20 years old living in Seoul and other metropolitan areas from March 2 to March 12, 2009. 815 copies of data were analyzed to examine a structural model and test research hypotheses using AMOS package. The study showed the extended TAM for smart clothing was validated empirically in predicting the individual’s acceptance of smart clothing and 5 hypotheses among 7 hypotheses were supported. Specifically, perceived ease of use, perceived usefulness, and clothing involvement were the factors affecting attitude toward smart clothing. Attitude toward smart clothing was influenced directly by perceived usefulness and clothing involvement but influenced indirectly by perceived ease of use. Acceptance intention toward smart clothing was influenced strongly by attitude. From a theoretical point of view, the study extended the TAM for smart clothing. Moreover, this study would be beneficial for those who would develop smart clothing by providing information about attitude and acceptance intention of smart clothing consumers.