• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.225-233
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• 2012

The research discusses interrelationship of structural and reliability importance measures which used in the probabilistic safety assessment. The most frequently used component importance measures, such as Birnbaum's Importance (BI), Risk Reduction (RR), Risk Reduction Worth (RRW), RA (Risk Achievement), Risk Achievement Worth (RAW), Fussel Vesely (FV) and Critically Importance (CI) can be derived from two structure importance measures that are developed based on the size and the number of Minimal Path Set (MPS) and Minimal Cut Set (MCS). In order to show an effectiveness of importance measures which is developed in this paper, the three representative functional structures, such as series-parallel, k out of n and bridge are used to compare with Birnbaum's Importance measure. In addition, the study presents the implementation examples of Total Productive Maintenance (TPM) metrics and alternating renewal process models with exponential distribution to calculate the availability and unavailability of component facility for improving system performances. System state structure functions in terms of component states can be converted into the system availability (unavailability) functions by substituting the component reliabilities (unavailabilities) for the component states. The applicable examples are presented in order to help the understanding of practitioners.

• Journal of Korean Library and Information Science Society
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• v.25
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• pp.441-474
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• 1996

Up to recently, information service have emphasized mainly on efficiencies of information collection, storage, process. But, now, many people take interest in criteria and evaluation on quality of information itself and its services because of growth of electronic materials and development of telecommunication. Especially, since the greater part of infomation is made gradually digital format, quality of information service regards as of great importance. This study attempts to investigate the quality problem in information services and its a n.0, pplication. Also, to su n.0, pport high quality, it is needed criteria of information services to evaluate and measure. To understand quality of information services, This articles deal with concept of quality on information related sector, quality management, the reason of importance of information quality, quality work of information services. There is little method to measure and evaluate quality of internet services. So it is necessary to study on internet quality, user's selection on its quality, and development on high quality site.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.4
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• pp.22-29
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• 2001

As the importance of software measurement increases, there are more researches developing the new software measure. Given the importance of object-oriented development techniques, one specific area where this has occurred is coupling measurement in object-oriented systems. This thesis presents the coupling measure COM based on the methods and OOC based on the classes in measuring the coupling of object-oriented systems. And, it evaluates them using the coupling properties suggested by Briand while it compares them with other coupling measures by applying them to a system developed in the language of C++programming language.

• Journal of Information Technology Applications and Management
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• v.15 no.4
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• pp.21-36
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• 2008

As the great disturbance from abusing credit cards in Korea becomes stabilized, credit card companies need to interpret credit-card delinquents classification models from the viewpoint of profit. However, hit ratio which has been used as a measure of goodness of classification models just tells us how much correctly they classified rather than how much profits can be obtained as a result of using classification models. In this research, we tried to develop a new utility-based measure from the viewpoint of profit and then used this new measure to analyze two classification models(Neural Networks and Decision Tree models). We found that the hit ratio of neural model is higher than that of decision tree model, but the utility value of decision tree model is higher than that of neural model. This experiment shows the importance of utility based measure for credit-card delinquents classification models. We expect this new measure will contribute to increasing profits of credit card companies.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.843-844
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• 2005

• Fashion & Textile Research Journal
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• v.2 no.5
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• pp.391-397
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• 2000

The purpose of the present research is to determine, for a sample of female college students, the effects of body-cathexis and importance of ideal body image on satisfaction with ready-to-wear. The sample included 177 female college students aged from 18 to 25. To measure the variables, an instrument was developed based on previous studies. Body-cathexis and importance of meeting the ideal body image were measured for five areas of body parts; head/upper body, lower body, height, weight, and torso. Satisfaction with ready-to-wear includes satisfaction with the fit at pant length, thighs, hips, waist, bust, and neckline, and with the variety in ready-to-wear. Research hypotheses were tested using multiple regression. The results showed that there was a positive impact of body-cathexis for a specific body area on ready-to-wear satisfaction which is related to the body area. The effect of importance of meeting the ideal body image on ready-to-wear clothing was different in regard to different areas of body parts.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.5
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• pp.877-892
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• 1996

The purpose of this was to test the interactive effects of usage situation and personal characteristics on perceived risk, importance of store attributes and store-type choice. The data were collected via a questionnaire from 601 housewives of ages 20's∼ 50's living in Seoul, Korea, and analyzed by factor analysis and repeated measure two-way ANOVA. The results of this study were as follows: First, the interactive effect of age and situation on economic risk was significant. Second, the significant infraction of age and situation on importance of product price/variety was found, and there were significant intractions of education and situation on importance of service/convenience, discount policy and product information sources/promotion. Third, the interactive effects of situation and personal characteristics (age, income, education or job) on store-type choice (brand chain store, discount store, department store, designer boutique, local store or a wholesale market) were significant.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.3
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• pp.94-105
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• 1995

Purposes of this study were to apply and examine that the importance-performance analysis(IPA) could be a useful park management tool. The IPA is an easily-applied technique developed in marketing field to measure attribute importance and performance. It displays them simultaneously on a 4-quardrant action grid; therefore, park managers can upgrade current services and address marketing strategies for various user segments. The children's grand park was selected as a study are. Two different types of questionaires were utilized for data analyses. They were collected from one respondent by on-site distribution or by mail survey, because attribute importance and performance should be rated before and after visiting a park, respectively. Then, total data was segmented systematically by 2 variables-age and benefit sought. Action grids from order to meet the needs of each segment. Several comments on both data collection methods and segment variables selection were described to improve the IPA in recreation settings for future researches.

• Communications for Statistical Applications and Methods
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• v.8 no.1
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• pp.257-269
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• 2001

The simulation is used to estimate an overflow probability in a stable parallel network with coupled inputs. Since the general simulation needs extremely many trials to obtain such a small probability, the fast simulation is proposed to reduce trials instead. By using the Cramer’s theorem, we first obtain an optimally changed measure under which the variance of the estimator is minimized. Then, we use it to derive an importance sampling estimator of the overflow probability which enables us to perform the fast simulation.

• IE interfaces
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• v.6 no.2
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• pp.67-78
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• 1993

In this paper, we deal with the application of the fuzzy sets theory to evaluate and estimate the system reliability under the fault tree analysis. We formulate the uncertainty of component reliability to fuzzy sets, and propose a procedure for obtaining the system reliability in case the system structure is described by fault tree. An importance measure of each component is proposed. Computer program for fuzzy fault tree analysis(FFTA) is developed using C language to obtain the system reliability and the component‘s fuzzy importance.