• Computers and Concrete
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• 제33권3호
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• pp.265-273
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• 2024

Predicting fracture properties requires an understanding of structural failure behaviour in relation to specimen type, dimension, and notch length. Facture properties are evaluated using various testing methods, wedge splitting test being one of them. The wedge splitting test was numerically modelled three dimensionally using the finite element method on self compacting concrete specimens with varied specimen and notch depths in the current work. The load - Crack mouth opening displacement curves and the angle of rotation with respect to notch opening till failure are used to assess the fracture properties. Furthermore, based on the simulation results, failure curve was built to forecast the fracture behaviour of self-compacting concrete. The fracture failure curve revealed that the failure was quasi-brittle in character, conforming to non-linear elastic properties for all specimen depth and notch depth combinations.

• 대한간호학회지
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• 제42권7호
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• pp.1079-1086
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• 2012

Purpose: The purpose of this study was to develop and evaluate psychometric properties of the instrument, Resuscitation Self-Efficacy Scale for nurses. Methods: This was a methodological study for instrument development and psychometric testing. The initial item pool derived from literature review and experts resulted in 30 items linked to resuscitation self-efficacy. A convenience sample of 509 Korean nurses from eleven academic teaching hospitals participated in a survey to examine psychometric properties of the scale. To examine construct validity, exploratory factor analysis and known-group comparison were used. Cronbach's coefficient alpha was used to determine the scale's internal consistency reliability. Results: The final scale included 17 items with four-component structure termed 'Recognition', 'Debriefing and recording', 'Responding and rescuing', and 'Reporting'. These four factors accounted for 57.5% of the variance. Each subscale and the total scale demonstrated satisfactory internal consistency: .82; .88; .87; .83; and .91 respectively. Experienced nurses reported significantly higher self-efficacy mean scores in both total and subscales compared to new graduate nurses. Conclusion: The Resuscitation Self-Efficacy Scale for nurses yields reliable and valid results in appraising the level of resuscitation self-efficacy for Korean nurses. Further study is needed to test and refine the scale.

• 동서간호학연구지
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• 제14권1호
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• pp.44-55
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• 2008

Purpose: This research concludes the 110 male and female elderlies who are over 60 years old in C welfare center of G city to examine the effect of self-esteem between leisure activity and life satisfaction. Method: The types of participation leisure consist of 20 questions in five different categories. To measure the value of life satisfaction, the scale of life satisfaction for the elderly which is developed by Choi (1986) is used. The self-esteem was measured by the scale developed by Rosenberg (1965) and translated by Jeon (1974). The data were analyzed by SPSS including frequency, ANOVA, Duncan, Pearson correlation coefficient and multiple regression. Result: There was significant relationship among leisure activity and life satisfaction (r= .410, p= .000), leisure activity and self-esteem (r= .432, p= .000) and life satisfaction and self-esteem (r= .765, p= .000). After testing how leisure activity has effect on the self-esteem, it appears to be 17.9% and after adding life satisfaction it increases to be 59.5%. Conclusion: Synthesizing all following results, there were needed to bepersonal and global effort in many ways to satisfy the economical need of the elderly, and more supports onincreasing participation of the elderly in leisure.

• 한국전자거래학회지
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• 제16권3호
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• pp.23-45
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• 2011

가상 공간의 익명성으로 인하여 개인들은 물리적 세계와 다른 자기를 가상 세계에서 창조한다. 본 연구의 목적은 물리적 세계의 자기와 가상 세계의 자기 사이에 존재하는 차이가 개인의 온라인 커뮤니티 활동에 어떠한 영향을 미치는지 고찰하는 것이다. 먼저, 자기차이이론(Self discrepancy theory)을 기반으로 자기차이에 대한 개념적 정의를 도출하고 자기차이를 가상 세계 내에 존재하는 자기차이(Self-discrepancy in virtual world)와 물리적 세계와 가상 세계 사이에서 존재하는 자기차이(Cross-world self-discrepancy)로 세분화 하였다. 또한 각각의 자기차이를 요인 분석을 통하여 개인적 자기차이(Personal self-discrepancy)와 사회적 자기차이(Social self-discrepancy)로 구분하였다. 도출된 서로 다른 유형의 자기차이가 개인의 커뮤니티 지속사용 및 지식 기여 사이에 어떠한 영향을 미치는지 이론적 모형을 개발하고, 수집된 300개의 설문자료를 바탕으로 이를 검증하였다. 분석 결과, 가상 세계 내에서 존재하는 자기차이는 지각된 자기표현 유용성에 부의 영향을 미치는 반면, 가상 세계와 물리적 세계 사이에 존재하는 자기차이는 자기표현 유용성에 정의 영향을 미치는 것으로 나타났다. 또한 지각된 자기표현 유용성과 사용 용이성은 커뮤니티 지속 사용과 지식기여에 모두 정의 영향을 미치는 것으로 나타났다. 본 연구는 전통적인 자가차이 이론에서 논의되어온 자기에 대한 개념을 가상세계의 자기로 확장하였으며, 서로 다른 유형의 자기차이가 개인의 행위에 미치는 영향을 온라인 커뮤니티 정황에 적용함으로써 자기 개념에 대한 이론적 발전에 기여하였다.

• 한국의류학회지
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• 제37권7호
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• pp.922-934
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• 2013

This study investigates the motivations to purchase luxury brands by examining how individual characteristics (need for uniqueness, self-monitoring, and vanity) influence affective luxury brand attitudes and purchase intentions through two social function attitudes (self-expression attitude and self-presentation attitude) based on the functional theory of attitudes. On-line surveys were implemented and 314 consumers between the ages of 20 and 50 were recruited. Using SPSS 18.0 and AMOS 18.0, confirmatory factor analysis for measurements and structural equation modeling analysis for hypotheses testing were implemented. The results show that the need for uniqueness and self-monitoring by consumers have positive influences on self-expression and self-presentation attitudes toward luxury brands, respectively. The results indicate that the need by consumers for uniqueness motivates a self-expression attitude toward luxury brands and that the trait of self-monitoring motivates a self-presentation attitude toward luxury brands. Consumer vanity also positively influences both social function attitudes toward luxury brands. Self-expression and self-presentation attitudes toward luxury brands have positive influences on luxury brand purchase intentions through an affective attitude that facilitates a mediating role between two social function attitudes and the purchase intentions of consumers. This research contributes to a deeper understanding of the formation process of Korean consumers' purchase intentions for luxury brands and the literature on the role of related variables (need for uniqueness, self-monitoring, vanity, self-expression, self-presentation, affective attitude, and purchase intention). The findings provide a theoretical background to launch a cross-cultural study. The conclusion discusses the practical implications and limitations.

• 전기학회논문지
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• 제62권7호
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• pp.994-1002
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• 2013

This study suggests a generalized availability and safety evaluation model to evaluate the influences to the system's fault tolerant capabilities depending on automatic fault detection function such as the automatic periodic testings. The conventional evaluation model of automatic fault detection function deals only with the self diagnostics, and supposes that the fault detection coverage of self diagnostics is always constant. But all of the fault detection methods could be degraded. For example, the periodic surveillance test has the potential human errors or test equipment errors, the self diagnostics has the potential degradation of built-in logics, and the automatic periodic testing has the potential degradation of automatic test facilities. The suggested evaluation models have incorporated the loss or erroneous behaviors of the automatic fault detection methods. The availability and the safety of each module of the safety grade platform have been evaluated as they were applied the automatic periodic test methodology and the fault tolerant evaluation models. The availability and safety of the safety grade platform were improved when applied the automatic periodic testing. Especially the fault tolerant capability of the processor module with a weak self-diagnostics and the process parameter input modules were dramatically improved compared to the conventional cases. In addition, as a result of the safety evaluation of the digital reactor protection system, the system safety of the digital parts was improved about 4 times compared to the conventional cases.

• 비파괴검사학회지
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• 제27권2호
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• pp.115-123
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• 2007

본 연구에서는 탄소섬유로 보강된 콘크리트의 전기저항 변화를 모니터링하는 방법에 의해, 콘크리트의 파괴에 대한 자가진단 적용 특성을 검토하였다. 미분쇄 탄소섬유와 코크스 분체로 구성된 신형 리브재가 포함된 CFGFRP (탄소섬유 유리섬유 강화 플라스틱)와 콘크리트 보강용 CF(탄소섬유) 시트에 휨 하중 재하 단계별로 하중을 가할 때 균열 또는 파괴가 발생하기 전후의 탄소섬유의 전기저항 변화를 조사하여, 각 인자의 관계특성(각 하중단계별 전기저항, 변형률, 처짐 등의 변화)을 분석하였다. 그 결과, 콘크리트 인장측 파괴시 탄소섬유 보강근, 신형 리브, 시트가 파괴될 때, 전기저항은 크게 증가하지만, CFGFRP의 경우는 그 후 하이브리드 FRP 재료 중 탄소섬유를 보강하고 있던 유리섬유가 나머지 추가 재하 하중에 저항할 수 있어 콘크리트 시험체의 전 파괴단계에까지는 이르지 않았다. 따라서 CFGFRP의 보강근과 신형 리브, CF시트는 FRP로 보강된 콘크리트의 파괴를 사전에 감지할 수 있는 자가진단 재료로서의 적용이 가능함을 알 수 있었다.

• 대한간호학회지
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• 제46권2호
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• pp.293-304
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• 2016

Purpose: This methodological study was conducted to develop and psychometrically test the Transcultural Self-efficacy scale (TCSE-scale) for nurses. Methods: Initial 41 items for the TCSE-scale were generated based on extensive literature reviews and in-depth interviews with 18 nurses who had experience in caring for foreign patients. Cultural Competence and Confidence model was used as a conceptual framework. Content validity was evaluated by an expert panel. Psychometric testing was performed with a convenience sample of 242 nurses recruited from four general hospitals in the Seoul metropolitan area and Gyeonggi-do province of South Korea. To evaluate the reliability of TCSE-scale, a test-retest reliability and an internal consistency reliability were analyzed. Construct validity, concurrent validity, criterion validity, convergent validity and discriminative validity were used to evaluate the validity. Results: The 25-item TCSE-scale was found to have three subscales-Cognitive, Practical, and Affective domain-explaining 91.5% of the total variance. TCSE-scale also demonstrated a concurrent validity with the Cultural Competence Scale. Criterion-related validity was supported by known-group comparison. Reliability analysis showed an acceptable-to-high Cronbach's alpha-.88 in total, and subscales ranged from .76 to .87. The ICC was .90, indicating that the TCSE-scale has internal consistency and stability of reliability. Conclusion: This preliminary evaluation of the psychometric scale properties demonstrated an acceptable validity and reliability. The TCSE-scale is able to contribute to building up empirical and evidence based on data collection regarding the transcultural self-efficacy of clinical nurses. We suggest further testing of the applicability of TCSE-scale in different settings and community contexts.

• Restorative Dentistry and Endodontics
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• 제37권4호
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• pp.207-214
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• 2012

Objectives: This study evaluated the influence of chlorhexidine (CHX) on the microtensile bonds strength (${\mu}TBS$) of resin core with two adhesive systems to dentin in endodontic cavities. Materials and Methods: Flat dentinal surfaces in 40 molar endodontic cavities were treated with self-etch adhesive system, Contax (DMG) and total-etch adhesive system, Adper Single Bond 2 (3M ESPE) after the following surface treatments: (1) Priming only (Contax), (2) CHX for 15 sec + rinsing + priming (Contax), (3) Etching with priming (Adper Single Bond 2), (4) Etching + CHX for 15 sec + rinsing + priming (Adper Single Bond 2). Resin composite build-ups were made with LuxaCore (DMG) using a bulk method and polymerized for 40 sec. For each condition, half of specimens were submitted to ${\mu}TBS$ after 24 hr storage and half of them were submitted to thermocycling of 10,000 cycles between $5^{\circ}C$ and $55^{\circ}C$ before testing. The data were analyzed using ANOVA and independent t-test at a significance level of 95%. Results: CHX pre-treatment did not affect the bond strength of specimens tested at the immediate testing period, regardless of dentin surface treatments. However, after 10,000 thermocycling, all groups showed reduced bond strength. The amount of reduction was greater in groups without CHX treatments than groups with CHX treatment. These characteristics were the same in both self-etch adhesive system and total-etch adhesive system. Conclusions: 2% CHX application for 15 sec proved to alleviate the decrease of bond strength of dentin bonding systems. No significant difference was shown in ${\mu}TBS$ between total-etching system and self-etching system.

• Restorative Dentistry and Endodontics
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• 제28권3호
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• pp.203-208
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• 2003

The purpose of this study was to evaluate the effect of salivary contamination of teeth on bonding efficacy of self-priming and self-etching DBSs. The materials used were Single Bond(SB, self-priming system, 3M), Unifil Bond(UB, self-etching system, GC), and Scotchbond Multi-Purpose Plus(SM, 3M) as control. Forty five human molars randomly allocated to three groups as dentin bonding systems tested and embedded in epoxy resin. Then the specimens were wet-ground to expose flat buccal enamel surface or flat occlusal dentin surface and cut bucco-lingually to form two halves with slow speed diamond saw. One of them was used under non-contamination, other under contamination with saliva. The bonding procedure was according to the manufacturer's directions and resin composite(Z-100, 3M Dental Products, St. Paul, MN) was built-up on the bonded surface 5mm high. The specimens were ground carefully at the enamel-composite interface with fine finishing round diamond bur to create an hour-glass shape yielding bonded surface areas of $1.5{\pm}0.1\textrm{mm}^2$. The specimens were bonded to the modified microtensile testing apparatus with cyanoacrylate, attached to the universal testing machine and stressed in tension at a CHS of 1mm/min. The tensile force at failure was recorded and converted to a tensile stress(MPa). Mean values and standard deviations of the bond strength are listed in table. One-way ANOVA was used to determine significant difference at the 95% level. The bond strength of SBMP and SB were not affected by salivary contamination, but that of UB was significantly affected by salivary contamination. These results indicate that DBSs with total etch technique seems less likely affected by salivary contamination in bonding procedure.