• Journal of Life Science
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• v.12 no.6
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• pp.765-768
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• 2002

Enantioselective hydrolysis of racemic styrene oxide by Rhodotorula sp. CL-82 was investigated. Reaction conditions including pH, temperature, and volume ratio of organic cosolvent were optimized using response surface methodology, and the optimal conditions of pH, temperature, and the volume ratio of cosolvent were determined to be 7.64, $33.26^{\circ}C$, and 3.09 %(v/v), respectively. Chiral (S)-phenyl oxirane could be obtained with high enantiomeric purity (ee ＞ 99%) and 20% yield (theoretical yield ＝ 50%) at the optimal rendition.

• Korea journal of population studies
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• v.12 no.2
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• pp.56-68
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• 1989

The methodology in historical demography comprises the three core areas the family reconstitution method at the Institut National d' Ftudes Demographiques(I.N.E.D), the back projection at the Cambridge Group for the History of PopuJation and Social Struc-ture(HPSS). and the household-pattern analysis at the Cambridge Group and at the California Institute of Technology. The paper presents an outline of the family reconstitu-tion method and discusses the problems, both theoretical and methodological, arising from the problematic back projection vis-a-vis the usual inverse projection developed by Ronald D. Lee at Berkeley. Recent developments in the tield of the generalized inverse projection method designed 10 supplement the defects in the back projection and the inverse projection are presented. and for ease of explanation of the parish register data for the family reconstitution form (FRE). pre-modern Korean household register data are presented along with the parish register data of England and Wales that constitute the backbone of historical demography in pre-modern Europe. Possibilities of exploring the household pattern analysis method based on the Laslett-Hammel classification scheme for the mid-eighteenth-century Korean household register data are suggested.

• Journal of Family Resource Management and Policy Review
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• v.2 no.1
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• pp.47-57
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• 1998

This paper delves into philosophical aspects of institutional household(IH) study. The paper argues that it is also necessary to investigate theoretical, methodological, and philosophical issues, not only prescriptive, practical, and managerial ones, in order to establish a field of study as an independent area of academic discipline. In that sense the paper is expected to contribute to the establishment of "the science of IH" as well as the growth of knowledge in that field. For philosophical discussions, the paper first reviews overall sub-fields of philosophy of science such as ontology, epistemology, methodology, and the debate on human nature. Then, it focuses on philosophical issues relating to the nature of IH including (1) the substance of institutional household as scientific investigation, (2) the epistemological basis of IH study, (3) the possibility of normal methodology in studying IH, (4) the values that IH ought to pursue, and (5) the rationale and autonomy of IH study. In the conclusion section, the paper discusses why the study on philosophical aspects in IH is critical in academic community of family resource management.anagement.

• Communications for Statistical Applications and Methods
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• v.24 no.6
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• pp.543-559
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• 2017

Tree-based regression and classification ensembles form a standard part of the data-science toolkit. Many commonly used methods take an algorithmic view, proposing greedy methods for constructing decision trees; examples include the classification and regression trees algorithm, boosted decision trees, and random forests. Recent history has seen a surge of interest in Bayesian techniques for constructing decision tree ensembles, with these methods frequently outperforming their algorithmic counterparts. The goal of this article is to survey the landscape surrounding Bayesian decision tree methods, and to discuss recent modeling and computational developments. We provide connections between Bayesian tree-based methods and existing machine learning techniques, and outline several recent theoretical developments establishing frequentist consistency and rates of convergence for the posterior distribution. The methodology we present is applicable for a wide variety of statistical tasks including regression, classification, modeling of count data, and many others. We illustrate the methodology on both simulated and real datasets.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.39.1-39.1
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• 2016

The cosmic distance can be precisely determined using a 'standard ruler' imprinted by primordial baryon acoustic oscillation (hereafter BAO) in the early Universe. The BAO at the targeted epoch is observed by analyzing galaxy clustering in redshift space (hereafter RSD) of which theoretical formulation is not yet fully understood, and thus makes this methodology unsatisfactory. The BAO analysis through full RSD modeling is contaminated by the systematic uncertainty due to a non--linear smearing effect such as non-linear corrections and uncertainty caused by random viral velocity of galaxies. However, BAO can be probed independently of RSD contamination using the BAO peak positions located in the 2D anisotropic correlation function. A new methodology is presented to measure peak positions, to test whether it is also contaminated by the same systematics in RSD, and to provide the radial and transverse cosmic distances determined by the 2D BAO peak positions. We find that in our model independent anisotropic clustering analysis we can obtain about 2% and 5% constraints on $D_A$ and $H^{-1}$ respectively with current BOSS data which is competitive with other analysis.

• Journal of Power Electronics
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• v.16 no.1
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• pp.121-132
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• 2016

In this paper, high-efficiency design methodology of a zero-voltage-switching full-bridge (ZVS-FB) pulse width modulation (PWM) converter for server-computer power supply is discussed based on self-driven synchronous rectifier (SR) performance. The design approach focuses on rectifier conduction loss on the secondary side because of high output current application. Various-number parallel-connected SRs are evaluated to reduce high conduction loss. For this approach, the reliability of gate control signals produced from a self-driver is analyzed in detail to determine whether the converter achieves high efficiency. A laboratory prototype that operates at 80 kHz and rated 1 kW/12 V is built for various-number parallel combination of SRs to verify the proposed theoretical analysis and evaluations. Measurement results show that the best efficiency of the converter is 95.16%.

• Nuclear Engineering and Technology
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• v.50 no.7
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• pp.1168-1172
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• 2018

This study went beyond making an indicator simply based on theoretical arguments, and explored a wide spectrum of different types of perceptions about energy safety to make a concept of energy safety for the Korean society. The energy safety schemata of people can be divided into three types. Type1 is concern about multi-level risks-responsibility-centric, type2 is concern about security and personal burden-expertise-centric, and type3 is concern about health and personal burden-responsibility-centric. Questions were designed on the basis of the characteristics, differences and commonalities of the three types of perceptions, explored through the Q methodology, and Koreans' perception of nuclear safety was examined. Based on the results of this research the following components of trust in nuclear safety were derived, risk perception, responsibility, honesty, expertise and procedural justification. The items for specifically evaluating them were developed, and factor analysis was conducted, and as a result, the validity of each item was proven. The components of the nuclear safety trust indicator do not exist independently, but influence each other continuously through interactions. For this reason, rather than focusing on any one of them, laws and systems must be improved first so that they can move together in one big frame.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.61-66
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• 2022

The main purpose of the article is to analyze the key aspects of didactic games and exercises in the sensory development of preschoolers. The relevance of the chosen subject determines the fact that there are a number of problems in the specifics of the development of preschoolers and their characteristics, which manifest themselves individually. The importance of using didactic games and exercises in the development of preschoolers has been proved. The methodology includes a number of theoretical and practical methods, which together form the research methodology. Based on the results of the study, key aspects of the importance of the influence of dadactic games and exercises in the sensory development of preschoolers were identified. Further research requires the question of analyzing modern technologies for the formation of modern methods of sensory development for preschoolers.

• Korean Journal of Adult Nursing
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• v.21 no.6
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• pp.666-677
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• 2009

Purpose: This study was to test a theoretical model examining the relationships among social support, illness demands, marital adjustment, family coping and family functioning in couples more than three years after breast cancer diagnosis. Methods: A causal modeling methodology was used to test the specified relationships in the recursive theoretical model. A total of 60 couples with breast cancer were recruited from January to April 2005. Five standardized questionnaires were used to measure the theoretical concepts: social support (ISSB), illness demands (DOII), marital adjustment (DAS), family coping (F-COPES), and family functioning (FACESII). Results: Path analysis results from the wives and the husbands revealed different patterns. Three hypotheses were supported in the wife model as predicted: social support and family coping, family coping and family functioning, and social support and marital adjustment (trend). Five hypotheses were supported in the husband model as predicted: social support and illness demands, also social support and marital adjustment, illness demands and marital adjustment, marital adjustment and family coping, and family coping and family functioning. Conclusion: This study provides valuable information for developing various interventions with social support for improving family functioning of breast cancer couples in the middle adaption stage (more than three years after diagnosis).

• International Commerce and Information Review
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• v.8 no.2
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• pp.59-78
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• 2006

Considering rapid development of Internet Portal Site Contents in Korea, it is an important issue to analyze consumers' satisfaction and e-loyalty. This research develops, and empirically test a model for explaining/predicting the satisfaction and e-loyalty with internet-based Electronic Trade Site. This paper describes a theoretical model for investigating the Satisfaction and e-Loyalty of the Electronic Trade Site. This study investigates the concept of the satisfaction, e-loyalty in Electronic Trade Site and its determinants, and tries to establish e-loyalty analyzing model. The model of the satisfaction, e-loyalty electronic trade site is tested here using data from 158 samples. Based on the research model, a comprehensive set of hypotheses is formulated and a methodology for testing them is outlined. some of the hypotheses are tested empirically to demonstrate the applicability of the theoretical model. In examining the relationships of the determinants factors, service quality satisfaction show in significantly by Reliability, Information Provided, Trustworthiness, Convenience, International of contents but that show in not significantly by Interaction. In addition, Electronic Trade site retention shows indirect effect between customer satisfaction and referral. Although our research can not show the determinants of e-loyalty in the electronic trade site the empirical result give both theoretical and managerial implication for managing the consumers' satisfaction and e-loyalty in electronic trade site.