• Title/Summary/Keyword: Criterion Factor

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Fracture criterion of mixed mode in adhesively bonded joints of Al/Steel dissimilar materials (Al/Steel 이종재료의 접착이음에 대한 혼합모드의 파괴기준)

  • Jeong, Nam-Yong;Jang, Jin-Mo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.8
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    • pp.1322-1331
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    • 1997
  • A method of strength evaluation applying fracture mechanics in the adhesively bonded joints of Al/Steel dissimilar materials was investigated in this paper. Various shapes of adhesively bonded Al/Steel scarf joints focussing on fracture criterion of mixed mode crack were prepared for the static tests. Also, stress intensity factors of the interface cracks in adhesively bonded joints of Al/Steel dissimilar materials were analyzed with 2-dimensional elastic program of boundary element method(BEM), and the experiment of fracture toughness were carried out under various mixed mode conditions. From the results, the fracture criterion and method of strength evaluation by the fracture toughness in adhesively bonded joints of Al/Steel dissimilar materials were proposed.

A Study on the Initial Crack Curving Angle of Isotropic/Orthotropic Bimaterial

  • Hawong, Jai-Sug;Shin, Dong-Chul;Lee, Ouk-Sub
    • Journal of Mechanical Science and Technology
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    • v.16 no.12
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    • pp.1594-1603
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    • 2002
  • In this paper, when the initial propagation angle of a branched crack is calculated from the maximum tangential stress criterion (MTSC) and the minimum strain energy density criterion (MSEDC), it is essential that you use stress components in which higher order terms are considered and stress components at the position in a distance 0.005㎜ from the crack tip (=r). When an interfacial crack propagates along the interface at a constant velocity, the initial propagation angles of the branched crack are similar. to the mode mixities (phase angle) and the theoretical values obtained from MTSC and MSEDC. The initial propagation angle of the branched crack depends considerably on the stress intensity factor K$_2$.

QoS Measurement Method of RTP/RTCP for Multimedia Service in BcN (BcN에서 멀티미디어 서비스를 위한 RTP/RTCP의 QoS 측정방법)

  • Lim Jae-Young;Kim Jeong-Ho
    • Proceedings of the Korea Contents Association Conference
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    • 2005.11a
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    • pp.611-615
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    • 2005
  • Having been multimedia services in BcN network, QoS is best important factor. This paper classify existing services and newly to be offered services, analyze quality criterion and measurement method for QoS guarantee in BcN, This paper investigate end-to-end quality criterion, classify measurement method existing and newly to be offered services, search quality criterion, introduce measurement method such as call success rate, packet loss rate, one-way delay, jitter and R-value for end-to-end quality measurement.

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Analysis of Mixed-mode Crack Propagation by the Movable Cellular Automata Method

  • Chai, Young-Suck;Lee, Choon-Yeol;Pak, Mikhail
    • International Journal of Precision Engineering and Manufacturing
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    • v.9 no.4
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    • pp.66-70
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    • 2008
  • The propagation of a mixed-mode crack in soda-lime silica glass is modeled by movable cellular automata (MCA). In this model, a special fracture criterion is used to describe the process of crack initiation and propagation. The results obtained using the MCA criterion are compared to those obtained from other crack initiation criteria, The crack resistance curves and bifurcation angles are determined for various loading angles. The MCA results are in close agreement with results obtained using the maximum circumferential tensile stress criterion.

A Network Analysis Approach to the Evaluation of Students' Laboratory Reports (계통도 분석법을 이용한 실험보고서 평가의 효과 분석)

  • Paik, Seoung-Hey;Pak, Sung-Jae
    • Journal of The Korean Association For Science Education
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    • v.12 no.1
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    • pp.93-101
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    • 1992
  • The purposes of this study were; 1) to apply the network analysis to evaluation of students' laboratory reports, 2) to test the applicability of the systematic network analysis. For this purposes, 7th grade 88 students from 22 middle schools in Inchon city of Korea were selected and their laboratory reports were evaluated by a evaluation criterion network developed in this study. The evaluation criterion consisted of 4 categories and 10 subcategories. The results of this study suggested that the network analysis approach was suitable one for the evaluation of students' laboratory reports. This was supported by total score distribution, means/weight, Cronbach's ${\alpha}$ coefficient(0.70), and the subcategories' reliabilities. The resluts of the factor analysis indicated that the evaluation criterion network of this study had two factors.

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A bootstrap approach for factor numbers in binary data (붓스트랩 방법을 이용한 이항분포자료에 대한 요인수 결정에 관한 연구)

  • 김성호;정미숙
    • The Korean Journal of Applied Statistics
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    • v.8 no.2
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    • pp.201-216
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    • 1995
  • A method of determining the factor numbers is explored in this paper, when data and the factors are binary. We applied a bootstrap approach and proposed a criterion for the method. Simulation results suggest that the proposed method in this paper is very useful in determining the factor numbers for binary data and factors.

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Evaluation and Analysis on the Image Decision Factors of Food Service Industry - Focused on Jeonju Local Food Service Industry - (외식업체 서비스 이미지 결정 요인 평가 분석 - 전주 지역 외식업체 중심으로 -)

  • Yang, Man-Kyu
    • Culinary science and hospitality research
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    • v.16 no.2
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    • pp.1-14
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    • 2010
  • This study is focused on the image benefit cost criterion value and the pure image benefit figure of the local food service industries, V, T, and O based on the theory and factor-analyses of food service industry. To accomplish the aim of this study, theoretical and positive research methods have been applied. The steps of food service image decision projects for the activating of identification on food service have been examined through theories and positive analyses. As the results, 'the image of menu service' appears to be the most effectual factor on the pure image benefit score, which is the priority order of the project planning for the food service image marketing of Jeonju area. As for the image benefit cost criterion value, 'the image of managemental service system', 'the image of approachability', and 'the service of internal surroundings' have been proved to be the most effectual factor in V, T, O respectively. On the other hand, this study shows that V manages its image of food service most effectually with 1.7 billion won, T with 96 million won, O with 7.2 million won for the image marketing strategy.

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Validity and Reliability of Korean Version of Post-traumatic Stress Disorder Scale (K-PTSD) Measuring Attitudes and Knowledge of PTSD (한국판 외상 후 스트레스 장애에 대한 태도와 지식 측정도구(K-PTSD)의 타당도와 신뢰도)

  • Bang, Kyung-sook;Bang, Hwal Lan;Hong, Sun-Woo;Lim, Jihee
    • The Journal of Korean Academic Society of Nursing Education
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    • v.26 no.1
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    • pp.47-55
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    • 2020
  • Purpose: The aim of this study was to examine the validity and reliability of the Korean version of the PTSD scale (K-PTSD) for measuring attitudes and knowledge of PTSD. Methods: A cross-sectional study design was used. The K-PTSD scale consisted of 8 items for attitudes, 8 items for general knowledge of PTSD, and 3 items for knowledge of PTSD treatment; 211 nursing students and paramedic students participated. Content validity, item analysis, and factor analysis were used to examine the construct validity. Criterion validity was tested by using educational experience with PTSD as a criterion. Cronbach's α was used to identify internal consistency reliability in the attitude scale. Results: Construct validity of the K-PTSD was verified by exploratory factor analysis, with factor loadings for attitude ranging from .59 to .84. Criterion validity in comparing knowledge of PTSD (t=2.02, p=.044) and PTSD treatment (t=3.19, p=.022) showed a significant difference according to PTSD educational experience. Cronbach's α for the attitude scale was .79 and .59. Conclusion: The findings suggest that the K-PTSD is a valid and reliable tool that can measure attitudes and knowledge of PTSD among nursing and paramedic students. However, further study is needed to retest the verification of this scale with more diverse participants.

Reliability and Validity of the Korean Version of Nurses' Attitudes and Preparedness towards Delegation (한국어판 간호사의 위임에 대한 태도 및 준비성 측정도구의 타당도와 신뢰도)

  • Kim, Miyoung;Park, Jinhwa;Choi, Miran
    • Journal of Korean Academy of Nursing Administration
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    • v.22 no.1
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    • pp.11-21
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    • 2016
  • Purpose: The purpose of this study was to develop and test the validity and reliability of the Korean version of nurses' attitudes toward delegation and preparedness to delegate (APD). Methods: The Korean version of APD was developed through forward-backward translation methods. Internal consistency reliability, criterion validity, and construct validity using exploratory and confirmatory factor analysis were conducted using IBM SPSS Statistics 19 and AMOS 20.0. Survey data were collected from 161 nurses working in 2 general hospitals. Results: The Korean version of APD showed Cronbach's alphas of .68 and .85. Factor loadings of the 8 attitude items on the 3 subscales ranged from .60 to .86 and the 15 preparedness items on the 4 subscales ranged from .47 to .90. The model of 3 subscales for the Korean nurses' attitude toward delegation and the model of 4 subscales for the Korean nurses' preparedness to delegate were both validated by confirmatory factor analysis(NC<3, CFI>.90, RMSEA<.10). Criterion validity compared to job satisfaction showed significant correlation. Conclusion: The findings of this study demonstrate that this modified Korean version of APD is applicable for measuring Korean nurses' attitude toward delegation and preparedness to delegate.

Development of the Meaning in Life Scale for Older Adults (노인의 삶의 의미 측정 도구 개발)

  • Lee, Si Eun;Hong, Gwi-Ryung Son
    • Journal of Korean Academy of Nursing
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    • v.47 no.1
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    • pp.86-97
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    • 2017
  • Purpose: The purpose of this study was to develop and test the psychometric properties of the newly developed instrument, Meaning in Life, for elderly Korean people. Methods: Ten older adults participated in the qualitative research used to develop the initial items. Participants for the psychometric testing were 371 community-dwelling older adults. Validity and reliability analyses included content, construct, and criterion-related validities, internal consistency, and test-retest reliability. Results: The Meaning in Life Scale consisted of 12 items with three distinct factors; value of life, source of life, and will to live, which explained 86.7% of the total variance. A three-factor structure was validated by confirmatory factor analysis. Criterion-related validity was supported by comparison with the Purpose in Life Test (r=.74). Reliabilities were secured with test-retest reliability of Intra-class Correlation Coefficient (ICC) .85 and the Cronbach's alpha coefficient .90. Conclusion: The results of this study indicate that this instrument is useful to measure meaning in life in Korean elders.