• Title/Summary/Keyword: Fit Factor

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Numerical Design Approach to Determining the Dimension of Large-Scale Underground Mine Structures (대규모 지하 광산 구조물의 규모 결정을 위한 수치해석적 설계 접근)

  • Lee, Yun-Su;Park, Do-Hyun;SunWoo, Choon;Kim, Gyo-Won;Kang, Jung-Seok
    • Tunnel and Underground Space
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    • v.22 no.2
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    • pp.120-129
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    • 2012
  • Recently, mining facilities have being installed in an underground space according to a social demand for environment-friendly mine development. The underground structures for mining facilities usually requires a large volume of space with width greater than height, and thus the stability assessment of the large-scale underground mine structure is an important issue. In this study, we analysed a factor of safety based on strength reduction method, and proposed a numerical design approach to determining the dimension of underground mine structures in combination with a strength reduction method and a multivariate regression analysis. Input design parameters considered in the present study were the stress ratio and shear strength of rock mass, and the width and cover depth of underground mine structures. The stabilities of underground mine structures were assessed in terms of factor of safety under different conditions of the above input parameters. It was calculated by the strength reduction method, and several kinds of fit functions were obtained through various multivariate regression analyses. Using a best-fit regression model, we proposed the charts which provide preliminary design information on the dimension of underground mine structures.

Effects of Climatic Condition on Stability and Efficiency of Crop Production (농업 기상특성과 작물생산의 효율 및 안전성)

  • Robert H. Shaw
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.27 no.4
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    • pp.296-313
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    • 1982
  • At a time when world population and food supply are in a delicate balance, it is essential that we look at factors to improve this balance. We can alter the environment to better fit the plant's needs, or we can alter the plant to better fit the environment. Improved technology has allowed us to increase the yield level. For moderately detrimental weather events technology has generally decreased the yield variation, yet for major weather disasters the variation has increased. We have raised the upper level, but zero is still the bottom level. As we concentrate the production of particular crops into limited areas where the environment is closest to optimum, we may be increasing the risk of a major weather related disaster. We need to evaluate the degree of variability of different crops, and how weather and technology can interact to affect it. The natural limits of crop production are imposed by important ecological factors. Production is a function of the climate, the soil, and the crop and all activities related to them. In looking at the environment of a crop we must recognize these are individuals, populations and ecosystems. Under intensive agriculture we try to limit the competition to one desired species. The environment is made up of a complex of factors; radiation, moisture, temperature and wind, among others. Plant response to the environment is due to the interaction of all of these factors, yet in attempting to understand them we often examine each factor individually. Variation in crop yields is primarily a function of limiting environmental parameters. Various weather parameters will be discussed, with emphasis placed on how they impact on crop production. Although solar radiation is a driving force in crop production, it often shows little relationship to yield variation. Water may enter into crop production as both a limiting and excessive factor. The effects of moisture deficiency have received much more attention than moisture excess. In many areas of the world, a very significant portion of yield variation is due to variation in the moisture factor. Temperature imposes limits on where crops can be grown, and the type of crop that can be grown in an area. High temperature effects are often combined with deficient moisture effects. Cool temperatures determine the limits in which crops can be grown. Growing degree units, or heat accumulations, have often been used as a means of explaining many temperature effects. Methods for explaining chilling effects are more limited.

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Development and Validation of a Career Decision-Making Scale for Scientifically Gifted Undergraduates (과학영재 대학생을 위한 진로결정 요인 척도개발 및 타탕화)

  • Yang, Tae-Youn;Han, Ki-Soon;Park, In-Ho
    • Journal of Gifted/Talented Education
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    • v.21 no.4
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    • pp.927-943
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    • 2011
  • What are the critical factors in deciding future career to the gifted and talented students? The present study started with this question, and was to develop a career decision-making scale for scientifically gifted undergraduates. For this, literatures related to the scientifically gifted/talent and scientists' career decision-making were reviewed and examined in depth. Based on the review of the related literature, the developed scale of career decision-making was comprised of 26 items in 6 factors, such as individual aptitude & self-realization, economic aspect, work & leisure, familial influence, parents/teachers' recommendation, and experience of science activity during the school days. For the preliminary exploratory factor analysis, 153 undergraduate students who were majoring in natural sciences and engineer participated in the study. For the confirmatory factor analysis, 264 undergraduates who were awarded the presidential scholarships and 93 undergraduates who completed a university-affiliated gifted education center participated. The results of the study are as follows. The fit of measurement model was found to be $x^{2}$=645.157 (df=279, p=.00), TLI=.924, CFI= .935, RMSEA=.061, indicating most of fit indexes were acceptable. Cronbach's ${\alpha}$ in each sub-factor was quite high, .82 for individual aptitude & self-realization, .94 for economic aspect, .84 for work and leisure, .88 for familial influence, .79 for patents/ teachers' recommendation, and .79 for experience of science activity during the school days. The results of the study were discussed whether the developed scale could be used as a valid and reliable tool for measuring career decision-making factors of the scientifically gifted undergraduates in our country.

An Evaluation Model for the Major Science Research Facilities and Equipments to Enhance the Competitiveness of the Science and Technology: A Focus on the Test of Reliability and Validity of the Model (과학기술 경쟁력 제고를 위한 대형연구시설 및 장비 평가모형 분석 : 모형의 신뢰성 및 타당성 검토를 중심으로)

  • Kwon, Gi-Heon;Cha, Yong-Jin;Lee, Hong-Jae
    • Journal of Korea Technology Innovation Society
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    • v.10 no.1
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    • pp.121-142
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    • 2007
  • The purpose of this study is to construct the evaluation model for the major science research facilities and equipments to enhance the competitiveness of the science and technology and also to test the reliability and validity of the model. To achieve the purposes, this study theoretically reviews the concept of the major science research facilities and equipments and their characteristics. Through a review of literature, this study draws 11 criteria for evaluating the priorities of the major science research facilities and equipments. These criteria are categorized as two dimensions - 'science & technology' and 'national policy'. The dimension of science & technology includes scientific importance, technological readiness, utilization rate, common utilization rate, and ability of management and operation. The national policy dimension contains degree of correspondence with national science development, imperativeness of national policy, science and technical effectiveness, economic and industrial effectiveness, responsiveness of research demand, and equity among the related institutions. The competitiveness of the science and technology consists of these two dimensions. The evaluation model is established on the framework of criteria. The 18 major science research facilities and equipments are selected through a series of Delphi. The survey of experts (BT, ET, IT, NT and ST) is also implemented to evaluate the 18 major science research facilities and equipments by 11 criteria. The overall results indicate that the reliability and validity of the model are good. The reliability tests show that the five indicators of science & technology and the six indicators of national policy have high internal consistencies. The confirmatory factor analyses reveal that the two constructs - 'science & technology' and 'national policy' - have high convergent and discriminant validity. The correlational analyses also show that the criteria-related validity between them is high. Furthermore, the results of higher order factor analysis indicate that the fit indices of the model are high and suggest a good fit to the data. Based on these findings, the policy implications of the model are discussed.

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Development and Validation Study of the Korean Version of Working Relationship Scale (한국형 실천관계 척도 정신장애인 용 개발 연구)

  • Kwon, Jayoung
    • Korean Journal of Social Welfare
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    • v.65 no.3
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    • pp.239-263
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    • 2013
  • This research was carried out in order to develop and validate the Korean Version of Working Relationship Scale for Mentally Disabled Persons, which measures the working relationship between a mentally disabled person and his or her case manager. The first step taken to develop this scale was to construct sample items for the Working Relationship Scale using literature research and three focus group interviews of mentally disabled persons who use local mental health services. Secondly, mentally disabled people were surveyed with these sample items and two professors from the department of social work who specialize in mental health social work and two licensed mental health social workers working in the community mental health field reviewed these sample items to select and compile a final version of the scale. Lastly, the scale's reliability and validity was verified through an empirical study of 569 mentally disabled persons who surveyed the final selection of items. An explanatory factor analysis showed that the sample items can be grouped into three factors. Factor 1 is 'Professional Contribution Factor,' which is related to the professional practice of the case manager; Factor 2 is 'Negative Working Relationship Factor'; and Factor 3 is 'Emotional Bond Factor,' which measures the intimacy between the case manager and the mentally disabled person. A confirmatory analysis of the three-factor format that was discovered in the explanatory factor analysis was carried out with the rest of the randomly divided data, which showed that the model demonstrated a goodness-of-fit. The convergence validity between similar concepts appeared to be appropriate as well. Based on these results, the Korean Version of Working Relationship Scale for Mentally Disabled Persons consisting of a final 33 items is developed and proposed and its implications in social work are discussed.

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Exploring the constructs of school happiness of elementary students (초등학생의 학교 행복감 구성요인 탐색)

  • Kang, Young-Ha
    • The Korean Journal of Elementary Counseling
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    • v.11 no.2
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    • pp.219-235
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    • 2012
  • The purpose of this study was to identify the factors of school happiness of elementary students by implicit theory. For this purpose, 192 items for happiness were constructed based on 76 5th and 6th elementary students' free descriptions. Then 75 items were selected for preliminary factor analysis based on item appropriateness by evaluation of 28 elementary teachers. The happiness inventory composed 136 items was administered to 155 students and 36 items were selected based on exploratory factor analysis results. 4 factors-optimism, positive peer-relationship, self-esteem, consideration, and teacher-relationship-were extracted by principal component analysis. The confirmatory factor analysis indices indicated that 4 factor model of happiness was fit. The reliability(Cronbach's ${\alpha}$) was .996.

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Validity and Reliability of the Korean Version of the Menopause-Specific Quality of Life (한국어판 폐경 특이형 삶의 질 측정도구의 신뢰도와 타당도 검증)

  • Park, Jin-Hee;Bae, Sun Hyoung;Jung, Young-Mi
    • Journal of Korean Academy of Nursing
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    • v.50 no.3
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    • pp.487-500
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    • 2020
  • Purpose: This study aimed to evaluate the validity and reliability of the Korean version of Menopause-Specific Quality of Life (MENQOL). Methods: The MENQOL was translated into Korean according to algorithm of linguistic validation process. A total of 308 menopausal women were recruited and assessed using the Korean version of MENQOL (MENQOL-K), the World Health Organization Quality of Life Brief Version (WHOQOL-BREF), and Center for Epidemiological Studies Depression Scale (CES-D-K). In estimating reliability, internal consistency reliability coefficients were calculated. Validity was evaluated through criterion validity and construct validity with confirmatory factor analyses using SPSS 23.0 and AMOS 25.0 software. Results: In item analyses, the "increased facial hair" symptom was excluded because of the low contribution of MENQOL-K. The confirmatory factor analysis supported good fit and reliable scores for MENQOL-K model, and the four-factor structure was validated (χ2=553.28, p<.001, NC=1.84, RMSEA=.05, AGIF=.85, AIC=765.28). The MENQOL-K consists of 28 items in 4 domains, including vasomotor (3 items), psychosocial (7 items), physical (15 items), and sexual subscales (3 items). There was an acceptable criterion validity with moderately significant correlation between MENQOL-K and WHOQOL-BREF. The Cronbach's α for the 4 subsacles ranged from .80 to .93. Conclusion: The MENQOL-K is a valid and reliable scale to measure condition-specific quality of life for perimenopausal and postmenopausal women. It can be used to assess the impact of menopausal symptoms on the quality of life of Korean women in clinical trials.

Factor Constructs Exploration and Model Goodness-of-fit Verification of Empathy for Dementia Patient among Nurses (간호사의 치매환자에 대한 공감도 요인구조 탐색 및 모형적합성 검증)

  • Back, Kyung-Mi;Lee, Hye-Kyung;Back, Jong-Nam
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.2
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    • pp.287-295
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    • 2020
  • The purpose of this study is to analyze what constitutes the sympathetic component of nurses care of dementia patients. For this study, 219 nurses in nursing dementia patients were treated in nursing hospitals. Using the Empathy Consensus Rating Scale (ECRS), basic model extraction, model modification, and model suitability verification were performed through factor structure search and confirmation factor analysis (CFA). The results of this study confirmed the validity and reliability of the constituents with 49 questions, including 3 factors including the acceptance of other emotions, the suppression of one's own emotions, and the exchange and interaction of emotions. According to these results, it is expected that the ECRS that can secure validity and reliability can be used for the study to confirm the nurse's Empathy in the dementia patients' nursing field.

Development of a Triage Competency Scale for Emergency Nurses (응급실 간호사의 중증도 분류 역량 측정도구 개발)

  • Moon, Sun Hee;Park, Yeon Hwan
    • Journal of Korean Academy of Nursing
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    • v.48 no.3
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    • pp.362-374
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    • 2018
  • Purpose: This study aimed to develop a triage competency scale (TCS) for emergency nurses, and to evaluate its validity and reliability. Methods: Preliminary items were derived based on the attributes and indicators elicited from a concept analysis study on triage competency. Ten experts assessed whether the preliminary items belonged to the construct factor and determined the appropriateness of each item. A revised questionnaire was administered to 250 nurses in 18 emergency departments to evaluate the reliability and validity of the scale. Data analysis comprised item analysis, confirmatory factor analysis, contrasted group validity, and criterion-related validity, including criterion-related validity of the problem solving method using video scenarios. Results: The item analysis and confirmatory factor analysis yielded 5 factors with 30 items; the fit index of the derived model was good (${\chi}^2/df=2.46$, Root Mean squared Residual=.04, Root Mean Squared Error of Approximation=.08). Additionally, contrasted group validity was assessed. Participants were classified as novice, advanced beginner, competent, and proficient, and significant differences were observed in the mean score for each group (F=6.02, p=.001). With reference to criterion-related validity, there was a positive correlation between scores on the TCS and the Clinical Decision Making in Nursing Scale (r=.48, p<.001). Further, the total score on the problem solving method using video scenarios was positively correlated with the TCS score (r=.13, p=.04). The Cronbach's ${\alpha}$ of the final model was .91. Conclusion: Our TCS is useful for the objective assessment of triage competency among emergency nurses and the evaluation of triage education programs.

A Study on the Influence of Dimensions of Learning Organization to Job Satisfaction : Mediating Effect of Self-Efficacy (학습조직 구축요인이 직무만족에 미치는 영향에 관한 연구 -자기효능감의 매개효과를 중심으로-)

  • Lee, Sun-Kyu;Choi, Dong-Guk;Kim, Doo-Yul;Kang, Eun-Gu;Lee, Sang-Min
    • Journal of Digital Convergence
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    • v.12 no.7
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    • pp.113-121
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    • 2014
  • The main purpose of the study is the impacts of applying two dimensions of Learning Organization on Job Satisfaction and the mediating effect of the Self efficacy. As a result, Structural Factor had not positive effect and Human Factor had positive effect on the Job Satisfaction. The mediating effect of Self efficacy had significant effect between Learning Organization and Job Satisfaction. The result of this study is not presented at the existing research. Therefore, tthe supervisor should make efforts to develop skills for the management of learning organization in order to fit the nature of the group members.