• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.5
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• pp.423-430
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• 2012

An adaptive maximum power point tracking (MPPT) scheme employing a variable scaling factor is presented. A MPPT control loop was constructed analytically and the magnitude variation in the MPPT loop gain according to the operating point of the PV array was identified due to the nonlinear characteristics of the PV array output. To make the crossover frequency of the MPPT loop gain consistent, the variable scaling factor was determined using an approximate curve-fitted polynomial equation about linear expression of the error. Therefore, a desirable dynamic response and the stability of the MPPT scheme were maintained across the entire MPPT voltage range. The simulation and experimental results obtained from a 3 KW rated prototype demonstrated the effectiveness of the proposed MPPT scheme.

• Korean Journal of Childcare and Education
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• v.18 no.3
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• pp.37-59
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• 2022

Objective: The purpose of this study is to develop and validate a coparenting scales(mother's version) suitable for the Korean situation. Methods: In this study, mothers with one or more children were targeted. First, factor structure and construct validity were verified(N=412), and second, cross-validation and concurrent validity were verified(N=312). Results: The coparenting scale(mother's version) is largely composed of the mother's own coparenting and their spouse's coparenting. First, as a result of performing an exploratory factor analysis, three factors were extracted from the mother's own coparenting and their spouse's coparenting, and they were labeled parenting cooperation, parenting agreement, and parenting sharing. Through confirmatory factor analysis, 13 items were identified with three factors. Second, cross-validation was performed on a new group with confirmatory factor analysis, and as a result, validity was secured by satisfying the model validation criteria. In addition, the correlation between the existing scale and parenting efficacy was significant, thus securing concurrent validity. Conclusion/Implications: Through this study, the coparenting scale(mother's version) that was developed may provide practical guidelines for family coparenting by identifying mothers' perceptions of coparenting, and can be used in parent education and child-rearing policies.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.71-71
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• 2003

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a multifunctional cytokine that has been implicated in the regulation of pre-implantation embryo development across several species. The aim of this study was to determine the effects of mouse granulocyte-macrophage colony-stimulating factor (mGM-CSF) on development of porcine parthenotes and nuclear transferred embryos, and on their expression of implantation-related genes. In the presence of bovine serum albumin, mGM-CSF did not increase the percentage of oocytes that developed to the blastocyst stage and at day 7 did not increase oocyte cell number. Addition of 10 mM GM-CSF to protein-free culture medium significantly increased the compaction and blastocoel formation of 1- to 2-cell parthenotes and cloned embryos developing in vitro. However, cell number was not increased when they were cultured in the presence of GM-CSF. Semi-quantitative reverse transcripts polymerase chain reaction (RT-PCR) revealed that mGM-CSF enhances mRNA expression of the leukemia inhibitory factor receptor, but does not influence interleukin-6 or sodium/glucose co-transporter protein gene expression in blastocyst stage parthenotes. These results suggest that mGM-CSF may enhance viability of porcine embryos developing in vitro in a defined culture medium.

• Archives of design research
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• v.13 no.2
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• pp.73-80
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• 2000

In this study design information was separately defined form general product information and thus factors reflected in product design ion the basis of values and roles were extracted. The following is a classification of 5 different types of design factors divided according to their disposition. ·Innovation factor - element which previously did not exist or element related with explicit reformation ·Open factor - active element which not only improves current performance but also induces new functions through understanding of usage situations and new possibilities. ·Anterior factor - element which prolongs and develops the early development requirements of products through C.I. and P.I. related elements and characteristics of previous models and design strategy. Self-evidence factor - element related with function visualization through product structure which may make possible the consolidation of shape and function. Rigid factor - element, based on the human factors engineering, related with the safety and efficiency of users. This classification was obtained by defining major characteristics of products considering the target consumer and market characteristics. In this classification factor structuring design process which efficiently deducted a differentiated final product by synthesizing factors of higher importance as dominant factors was proposed. With this kind of factor structuring process, product differentiation may be achieved by bestowing individual characteristics to each product by combining design dominant factors associated with the product for a specific purpose from the stages of product concept development. Moreover, this may be used as an approach to actively correspond to the various and specific demands of the comsumer.

• Journal of The Korean Association For Science Education
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• v.33 no.5
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• pp.995-1006
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• 2013

The purposes of this study were to develop an instrument to measure high school students' systems thinking and to validate the scale. The scale of systems thinking was made up for 5 factors - systems thinking, mental model, shared vision, personal mastery, and team learning through analyses of related literature. Six items per factor were constructed and the scale consisted of a total of 30 items for the pretest. After exploratory factor analysis, the number of total items was reduced to 20 items. For the main test, 280 students were sampled from high school and analyzed valid cases were 260 students. The finding of the exploratory factor analysis indicated 5 factors in the model, and 4 items per single factor. The result of confirmatory factor analysis was generally appropriate and acceptable (5 factor model: $x^2/df$=1.275, TLI=.946, CFI=.959, RMSEA=.033). The reliability for 20 items turned out to be reliable because the Cronbach's alphas were .840 and .604~.723 per each factor. This study should be expanded to various school levels and should be standardized for further research. The subsequent studies regarding diverse learning program development and implementation and the verification on the students' impact within the developed program can be recommended.

• Journal of Korean Academy of Nursing
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• v.27 no.3
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• pp.601-613
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• 1997

This project was conducted using a survey method and through interviewing with four persons aged 60 years and over. An interview with an open-ended questionnaire was also used for elderly persons, families, oriental medicine doctor and nurses. topic-related literature review was also done. In total, 382 statements were derived. For content validity, nursing professionals were involved in this study, From that 48 items are developed. The subjects were 340 elderly persons over 60 years old. Data were collected duicing February and March 1997 and analyzed using the SPSS package The result are as follows. 1. Items with low Cronbach Coefficient alpha which means low correlation with total items were removed. 2. Factor analysis was done in order to confirm construct validity and eight factors were obtained from the results. The first factor, 'positive cognition of the aging process', the second factor, 'relationship network' the third factor, 'maintanence of physical functioning, the fourth factor', 'maintanence of peaceful mind' the fifth factor, 'keeping up with daily tasks' the sixth factor, 'continuous adequate body movement' the seventh factor,'involvement of religion in the elderly person's life and the eight factor', 'appropriate resting'. Cronbach Coefficient alpha for the 33 items was .9127 Based on the result, the following is suggested 1. It is anrticipated that the fundamental health of elderly person could be promoted by assessing healthy behaviors of elderly person with this assessment tool. 2. Further studies could be derived from this research. 3. Validity of this assessment tool should be further tested with and a larger sample of elderly person including in-patient elderly persons as well as nursing home residents.

• Korea Journal of Hospital Management
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• v.10 no.2
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• pp.26-44
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• 2005

The purpose of this study was to investigate these major factors on patient satisfaction, and to examine the affecting level of major factors in. The subjects in this study was 70 hospitals that were surveyed the hospital evaluation program containing the survey of patient satisfaction by KHIDI(Korea Health Industry Development Institute) from 1997 to 1999. The collected data was analysed SPSS for Windows(Ver 10.0). On basically, frequency analysis, t-test, and ANOVA was performed and, for more analysis, correlation analysis, factor analysis, multiple regression analysis, logistic regression analysis was utilized. According to this study, the major factors of inpatient satisfaction are divided 3 types facility factor, manpower factor, and service factor. And the major factors of outpatient satisfaction are analyzed 5 types; facility factor related direct medical service, facility factor related indirect medical services, manpower factor, pharmacy factor, and facility factor related utilization convenience. The importance of this study lies in the identification of major factors on hospital patient satisfaction.

• Safety and Health at Work
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• v.6 no.2
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• pp.97-103
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• 2015

Background: This paper describes the development of a scale for measuring safety climate. Methods: This study was conducted in six manufacturing companies in Iran. The scale developed through conducting a literature review about the safety climate and constructing a question pool. The number of items was reduced to 71 after performing a screening process. Results: The result of content validity analysis showed that 59 items had excellent item content validity index (${\geq}0.78$) and content validity ratio (> 0.38). The exploratory factor analysis resulted in eight safety climate dimensions. The reliability value for the final 45-item scale was 0.96. The result of confirmatory factor analysis showed that the safety climate model is satisfactory. Conclusion: This study produced a valid and reliable scale for measuring safety climate in manufacturing companies.

• BMB Reports
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• v.42 no.10
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• pp.631-635
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• 2009

The heat shock transcription factor (HSF) family consists of at least three members in mammals and regulates expression of heat shock proteins in response to heat shock and proteotoxic stresses. Especially, HSF1 is indispensable for this response. Members of this family are also involved in development of some tissues such as the brain and reproductive organs. However, we did not know the molecular mechanisms that regulate developmental processes. Involvement of HSFs in the sensory development was implicated by the finding that human hereditary cataract is associated with mutations of the HSF4 gene. Analysis of gene-disrupted mice showed that HSF4 and HSF1 are required for the lens and the olfactory epithelium, respectively. Furthermore, a common molecular mechanism that regulates developmental processes was revealed by analyzing roles of HSFs in the two developmentally-related organs.

• Korean Management Science Review
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• v.17 no.2
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• pp.151-159
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• 2000

This study applies factor analysis of an author cocitation frequency matrix derived from a database file that consists of a total of 1095 cited reference records taken from 95 citing decision support systems articles published in Korean journals. This study identified the influence of social psychology, cognitive psychology, management information systems, strategic management, and organizational behavior/organizational design to the development of group support systems, user-interface, and executive information systems research subspecialties. This research establishes a benchmark to be used in the future research, which is necessary to account for the ongoing changes in the intellectual development and structure of DSS Research in Korea before solid conclusion can be reached about the maturity and on-going development of the DSS field in Korean.