• Wind and Structures
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• 제9권3호
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• pp.179-191
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• 2006

Parent wind data are often acknowledged to fit a Weibull probability distribution, implying that wind epoch maxima should fall into the domain of attraction of the Gumbel (Type I) extreme value distribution. However, observations of wind epoch maxima are not fitted well by this distribution and a Generalised Extreme Value (GEV) analysis leading to a Type III fit empirically appears to be better. Thus there is an apparent paradox. The reasons why advocates of the GEV approach seem to prefer it are briefly summarised. This paper gives a detailed analysis of the errors involved when the GEV is fitted to epoch maxima of Weibull origin. It is shown that the results in terms of the shape parameter are an artefact of these errors. The errors are unavoidable with the present sample sizes. If proper significance tests are applied, then the null hypothesis of a Type I fit, as predicted by theory, will almost always be retained. The GEV leads to an unacceptable ambiguity in defining design loads. For these reasons, it is concluded that the GEV approach does not seem to be a sensible option.

• Computers and Concrete
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• 제19권3호
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• pp.305-313
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• 2017

A robust finite element based reinforced concrete bridge deck corrosion initiation model is applied for time-dependent probabilistic sensitivity analysis. The model is focused on uncertainties in the governing parameters that include variation of high performance concrete (HPC) diffusion coefficients, concrete cover depth, surface chloride concentration, holidays in reinforcements, coatings and critical chloride threshold level in several steel reinforcements. The corrosion initiation risk is expressed in the form of probability over intended life span of the bridge deck. Conducted study shows the time-dependent sensitivity analysis to evaluate the significance of governing parameters on chloride ingress rate, various steel reinforcement protection and the corrosion initiation likelihood. Results from this probabilistic analysis provide better insight into the effect of input parameters variation on the estimate of the corrosion initiation risk for the design of concrete structures in harsh chloride environments.

• 성인간호학회지
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• 제16권1호
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• pp.27-36
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• 2004

Purpose: The purpose of this study was to identify patterns and trends of hardiness studies and to suggest the direction of further research. Method : Forty-seven hardiness studies were collected through internet searching and were reviewed by some criteria. Result : The results showed that hardiness studies have increased rapidly since 1990's. Eighteen studies were thesis' for degrees and others were for non-degree research studies. All studies employed the non-experimental design, particularly correlational studies. In the sampling method, all studies used non-probability sampling. Most commonly used instrument for hardiness measurement was Pollock(1986)'s HRHS. In the majority of research, hardiness was treated both as a composite measure and 3 subscales. Hardiness-related concepts were 27 and classified into 5 categories such as health behavior, stress, adaptation, support, and others. Most common statistical technique was Pearson's correlation coefficient, followed by regression, ANOVA, path analysis. Conclusion : To be utilized as practical nursing knowledge, hardiness studies should be done with more empirical analysis such as experimental research, and Meta-analysis is needed to compare the effect size and significance of composit and 3 subscales of hardiness construct.

• 대한기계학회논문집A
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• 제24권9호
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• pp.2353-2360
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• 2000

Statistical fatigue properties of metallic materials are increasingly required for reliability design purpose. In this study, static and fatigue tests were conducted and the normal, log-normal, two -parameter Weibull distributions at the 5% significance level are compared using the Kolmogorov-Smirnov goodness-of-fit test. Parameter estimation were compared with experimental results using the maximum likelihood method and least square method. It is found that two-parameter Weibull distribution and maximum likelihood method provide a good fit for static and fatigue life data. Therefore, it is applicable to the static and fatigue life analysis of the spheroidal graphite cast iron. The P-S-N curves were evaluated using log-normal distribution, which showed fatigue life behavior very well.

• 영어어문교육
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• 제13권2호
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• pp.1-23
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• 2007

The purpose of this research is to explore the effects of systematic teaching English pronunciation and listening in English. Focusing on phonemes and words in pairs and sentences, the sound systems of the English and Korean languages are dealt with in conjunction with the test data. This paper first discusses the systemic, or primary interference and the habitual, or secondary interference that hinder comprehension of certain English sounds. Second, the analysis of input and output test data on the contrasting vowels and consonants shows statistic significance in terms of the probability (p value) of t-test. Third, the comparative data by means of percentile of right answers on contrasting vowel and consonant sounds expound the different sound systems of the English and Korean languages. With this data, problems in pronunciation of and listening to English, and the factors that may cause these problems are analyzed so that they can be used as a guideline for a systematic approach in teaching English learners, thus leading to more satisfactory performance.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.482-487
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• 2005

In the most current Turn-key bidding and Alternative design, is going to establish maintenance plan along with a economical assessment (VE/LCC assessment etc). Generally, establishment of maintenance plan is based on past experiences that are decided upon sensor position and amount with analytic or mechanical control section. But, it is more reasonable that maintenance plan based on level of significance for Probabilistic Risk, with presuming damage probability assessment of structural fracture scenarios. Therefore, in this study it is considered about the technique that an improved maintenance plan of railroad structures using PRA (Probabilistic Risk Assessment) on the basis of structural reliability theory. For this, in the paper, Preventive maintenance plan based on PRA is suggested with an application example of Pansong-Line (Line number 3) railway in Pusan works that actually executed Turn-key design.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2010년도 학술발표회
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• pp.581-585
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• 2010

This study introduced a Bayesian based frequency analysis in which the statistical trend seasonal analysis for hydrologic extreme series is incorporated. The proposed model employed Gumbel and GEV extreme distribution to characterize extreme events and a fully coupled bayesian frequency model was finally utilized to estimate design rainfalls in Seoul. Posterior distributions of the model parameters in both trend and seasonal analysis were updated through Markov Chain Monte Carlo Simulation mainly utilizing Gibbs sampler. This study proposed a way to make use of nonstationary frequency model for dynamic risk analysis, and showed an increase of hydrologic risk with time varying probability density functions. In addition, full annual cycle of the design rainfall through seasonal model could be applied to annual control such as dam operation, flood control, irrigation water management, and so on. The proposed study showed advantage in assessing statistical significance of parameters associated with trend analysis through statistical inference utilizing derived posterior distributions.

• 한국의상디자인학회지
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• 제2권2호
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• pp.155-171
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• 2000

This study is to measure and evaluate the sensibility image for textile pattern design based on the generation. Ten patterns classified by a practical survey on the market are presented. A questionnaire has 14 sensibility related words scaled by 7 point semantic differential method. The practical research is performed for 200 women screened by sensibility test for individual character analysis based on the generation. Each subject is answered by a face-to-face interview method to improve survey's accuracy, For statistical test about differences in treatment means, SAS package is used and analyzed through ANOVA, significance probability and mean, In summary, this paper has proposed the sensibility image scale for apparel pattern design to satisfy individual sensibility, The results of this study can be effectively applied to develop textile pattern design based on human sensibility.

• 대한산업공학회지
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• 제40권2호
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• pp.151-162
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• 2014

This study proposes an optimization model to plan the patient distribution and medical resource allocation considering the diverse characteristics of disaster. For reflecting the particularity of disaster response, we configured a few scenarios such as availability of emergency surgery of non-major medical staff and the change in number of patients estimated reflecting the uncertainty, urgency and convergence of disaster. And we finally tested the effects of the scenarios' combination on the objective function defined as maximum number of survival patients. Our experimental results are expected to highlight the significance of the proposed model as well as the applicability of scenarios under disaster response.

• Communications for Statistical Applications and Methods
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• 제12권2호
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• pp.305-312
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• 2005

In the cluster analysis, Hotelling's $T^2$ can be used to estimate the unknown number of clusters based on the idea of multiple comparison procedure. Especially, its threshold is obtained according to the probability of committing the type one error. Examples are used to compare Hotelling's $T^2$ with other classical location test statistics such as Sum-of-Squared Error and Wilks' $\Lambda$ The hierarchical clustering is used to reveal the underlying structure of the data. Also related criteria are reviewed in view of both the between variance and the within variance.