• 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.

• The Journal of Korean Academic Society of Nursing Education
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• v.21 no.1
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• pp.28-35
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• 2015

Purpose: The purpose of this study was to examine the effects of prior information about ICU environment on the anxiety and environmental stress of cardiac surgery ICU patients. Methods: A non-equivalent control group non-synchronized quasi-experimental research design was used. Participants were 60 (control 30, experimental 30) patients who had been admitted to ICU. Prior information about the ICU environment was provided to the experimental group. The anxiety level of subjects was measured by State-Trait Anxiety Inventory (STAI) and the stress level of subjects was measured by the Intensive Care Unit Environmental Stressor Scale (ICUESS). Data were analyzed using a Chi-square test or a Fisher's exact test, independent samples t-test, and paired samples t-test. Results: There was no difference in Anxiety (t=-0.58, p=.563), but there was a significant difference in environmental stress (t=10.46, p<.001). Conclusion: Providing prior information would be an effective nursing intervention to reduce environmental stress.

• Korean Journal of English Language and Linguistics
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• v.1 no.1
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• pp.187-209
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• 2001

This study attempts to supplement what is known about the influence of prior knowledge on second language listening comprehension. To do so, the study examines the effect of prior knowledge and language proficiency on the ability of L2 listeners to understand texts. The purpose of an experiment was to determine the effect of topic familiarity on the L2 listening comprehension ability of subjects who varied in L2 listening proficiency level. The subjects (N=117) were selected from a population of college students enrolled in the Departments of English and Business in Korea. English listening proficiency levels were designated on the basis of TOEFL listening scores. Subjects listened twice each to texts (more familiar and less familiar). After listening to each text, a ten-item objective test was administered to test the subjects' comprehension of the information presented in the text. Objective tests were analyzed. using repeated measures analysis. A post hoc test was conducted to identify the means that were significantly different. This study yielded the following results: (1) subjects with high prior knowledge comprehended texts significantly better than did subjects with low prior knowledge; (2) the level of L2 listening proficiency had a significant effect on the L2 listening comprehension of texts, but there was no interaction between prior knowledge and the level of L2 listening proficiency.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1413-1425
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• 2006

When X and Y have independent gamma distributions, we develop a Bayesian procedure for testing the equality of two gamma means. The reference prior is derived. Using the derived reference prior, we propose a Bayesian test procedure for the equality of two gamma means using fractional Bayes factor and intrinsic Bayes factor. Simulation study and a real data example are provided.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.1095-1106
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• 2005

When X and Y have independent two parameter exponential distributions, we develop a Bayesian testing procedures for the equality of two location parameters. The reference prior in non-regular exponential model is derived. Under this reference prior, we propose a Bayesian test procedures for the equality of two location parameters using fractional Bayes factor and intrinsic Bayes factor. Simulation study and some real data examples are provided.

• 한국데이터정보과학회:학술대회논문집
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• 2004.04a
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• pp.15-23
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• 2004

When X and Y have independent two parameter exponential distributions, we develop a Bayesian testing procedures for the equality of two location parameters. Under the noninformative prior, we propose a Bayesian test procedures for the equality of two location parameters using fractional Bayes factor and intrinsic Bayes factor. Simulation study and some real data examples are provided.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.521-524
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• 2008

Effect of prior deformation on the sliding wear of the ultra-fine grained (UFG) ferrite-martensite dual phase (DP) steel was investigated. The UFG DP steel was fabricated by the ECAP and subsequent intercritical annealing. The steel was cold rolled before the wear test, and the effect of the prior deformation on the wear was examined. The wear tests were carried out at various loads against a bearing steel ball. The wear rate of the UFG DP steel that did not experience the prior deformation was higher than that of the coarse-grained (CG) DP steel, because of more severe surface shear deformation. The wear rate of the specimens with prior deformation was much higher than that of the specimen without prior deformation. The deformed CG DP specimen showed higher rate than the deformed UFG DP specimen, and the rate-variation of the CG DP steel was much bigger under the same test condition.

• Korean Journal of Adult Nursing
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• v.12 no.3
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• pp.407-417
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• 2000

The purpose of this study was to examine the effect of preoperative teaching as a nursing intervention on the emotional status of the patients prior to surgery. The method of this study was Nonequivalent Control Group Non-Synchronize Design. The data were selected from H universuty hospital in Seoul, and they consisted of an experimental group-30patients, and a control group-30 patients. The questionnaire consisted of 28 Preoperative Stress Inventory(Kang, 1998), and 16 State- Trait Anxiety Inventory(Spielberger, 1972). The collected data were analized by means of frequency, percentage, $X^2$ test, t-test and paired t-test with SPSS WIN. The results of this study were as follows : 1. The level of stress prior to surgery was significantly lower for the preoperative teaching group than for the control group(t=2.61, p< .01). 2. The level of anxiety prior to surgery was not significantly lower for the preoperative teaching group than for the control group. 3. The difference level of the anxiety level the prior to surgery was significantly higher for the preoperative teaching group than for the control group(t=2.82, p< .01). In conclusion, preoperative teaching is a beneficial nursing intervention that has a positive effect on the stress and anxiety of patients prior to surgery. Therefore it is recommended to use the preoperative teaching program as a nursing intervention for patients prior to surgery.

• Journal of Korean Society for Quality Management
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• v.21 no.1
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• pp.108-120
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• 1993

In this article an economic life test sampling plan is considered for repairable products when the products in each lot have the same interfailure time distribution, but the mean time between failure (MTBF) of a lot varies from lot to lot according to a known prior distribution. A cost model is constructed which consists of test cost, accept cost, and reject cost. Determination of the optimal plan which minimizes the expected average cost per lot is discussed. Numerical examples are presented to illustrate the use of the proposed sampling plans and sensitivity analyses for parameters of the prior distribution are performed.