• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.1
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• pp.61-70
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• 2008

This paper investigates the modal acoustic power by a cascade of flat-plate airfoils interacting with homogeneous, isotropic turbulence. Basic formulation for the acoustic power upstream and downstream is based on the analytical theory of Smith and its generalization due to Cheong et al. The acoustic power spectrum has been expressed as the sum of cut-on acoustic modes, whose modal power is the product of three terms: a turbulence series, an upstream or downstream power factor and an upstream or downstream acoustic response function. The effect of these terms in the modal acoustic power has been examined. For isotropic turbulence gust, the turbulent series are only reducing factor of the modal acoustic power. The power factor tends to reduce the modal acoustic power in the upstream direction, although the power factor is liable to increase the modal acoustic power in the downstream direction. The modes close to cut-off are decreasing strongly, especially in the downstream direction. Therefore the modes close to cut-off don't contribute highly to the radiated acoustic power in the downstream direction, although the modal acoustic pressure is high for these modes.

• Journal of Korean Academy of Nursing
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• v.49 no.1
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• pp.80-91
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• 2019

Purpose: This study attempted to develop a scale that measures the level of patients' recognition of the nurses' care, based on Watson's caring theory, and confirmed its reliability and validity. Methods: The items were developed through a literature review and an expert content validity test. The questionnaires were administered to 285 inpatients of internal medicine and surgical units at two general hospitals. Construct validity was tested using exploratory and confirmatory factor analysis, and reliability was tested using Cronbach's alpha. Results: This process resulted in a preliminary scale composed of 34 items; We used item analysis and five exploratory factor analyses, and consequently selected 14 items composed of three factors (respect, genuineness, and relationality). The confirmatory factor analysis verified the model fit and convergent and discriminant validity of the final items; criterion validity was confirmed with the positive correlation with the measurement scale of the patient-perceived quality of nursing. The overall scale reliability had a Cronbach's alpha of .92, which indicated internal consistency and reliability. Conclusion: The developed scale showed content, construct, and criterion validity, and reliability, as well as convergent validity for each item and discriminant validity between the factors. This makes it suitable for use in a diverse range of future studies on nurse communication using structural equation models.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.6
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• pp.64-73
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• 1997

솔리드 모델러, 자동요소분할 기법, 4면체 특이요소, 응력확대계수의 해석 기능을 통합하여, 3차원 균열의 응력확대계수를 효율적으로 해석할 수 있는 시스템을 개발하였다. 균열을 포함하는 기하모델을 CAD 시스템을 이용하여 정의하고, 경계조건과 재료 물성치 및 절점밀도 분포를 기하모델에 직접 지정함으로써, 퍼지이론 에 의한 절점발생과 데로우니 삼각화법에 의한 요소가 자동으로 생성된다. 특히, 균열 근방에는 4면체 2차 특이요소를 생성시켰으며, 유한요소 해석을 위한 입력 데이터가 자동으로 작성되어 해석코드에 의한 응력 해석이 수행된다. 해석 후, 출력되는 변위를 이용하여 변위외삽법에 의한 응력확대계수가 자동적으로 계산되어 진다. 본 시스템의 효용성을 확인하기 위해, 인장력을 받는 평판내의 표면균열에 대해 해석하여 보았다.

• Proceedings of the KIEE Conference
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• 1987.11a
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• pp.367-370
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• 1987

A high-performance PWM technique in current-controlled AC to DC converter is introduced. This converter used information about source voltage vectors to make good PWM switching pattern that it can control the DC output voltage with reduced ripple factor and rapid response. In addition to reduction of harmonic current, AC input power factor can be controlled to leading or lagging by current reference. Simulation was made based on analytical approach and it showed a good agreement with theory.

• Fashion, Industry and Education
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• v.15 no.2
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• pp.25-35
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• 2017

In this study, causal relationships of belief-attitude-purchase intention for unfamiliar-branded cosmetics (UBC) were tested based on the theory of reasoned action. Data of 249 consumers who have purchased UBC were submitted to the descriptive statistics, exploratory factor analysis, and regression analysis with SPSS. In results of exploratory analysis, three factors of beliefs on UBC were generated and titled as ingredients, publicity, and subsidiary features. In regression analysis results, ingredient factor affected attitude toward UBC while publicity and subsidiary features did not influence attitude toward UBC. It implies that consumers build their attitude toward brands focusing on ingredients that are core elements of cosmetic products. Attitude toward UBC solely influenced purchase intention while the effect of social acceptance on purchase intention was not found. In conclusion, consumers depend much on ingredients when they purchase UBC so brands newly launched or brands without reputations need to focus more on an excellence in ingredients and special functions of UBC to appeal to consumers when penetrating to the new market.

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.3
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• pp.255-260
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• 2002

This paper describes a fuzzy-based system for analyzing the stress intensity factors (SIFs) of three-dimensional (3D) cracks. A geometry model, i.e. a solid containing one or several 3D cracks is defined. Several distributions of local node density are chosen, and then automatically superposed on one another over the geometry model by using the fuzzy knowledge processing. Nodes are generated by the bucketing method, and ten-coded quadratic tetrahedral solid elements are generated by the Delaunay triangulation techniques. The singular elements such that the mid-point nodes near crack front are shifted at the quarter-points, and these are automatically placed along the 3D crack front. The complete finite element(FE) model is generated, and a stress analysis is performed. The SIFs are calculated using the displacement extrapolation method. To demonstrate practical performances of the present system, semi-elliptical surface cracks in a inhomogeneous plate subjected to uniform tension are solved.

• Journal of the Korean Magnetic Resonance Society
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• v.27 no.4
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• pp.28-34
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• 2023

We study the linear-nonlinear quantum transport theory of Wannier-Landau transition system in the confinement of electrons by a square well confinement potential. We use the projected Liouville equation method with the ensemble density projection technique. We select the dynamic value under a linearly oscillatory external field. We derive the dynamic value formula and the memory factor functions in three electron phonon coupling systems and electron impurity coupling systems of two transition types, the intra-band transitions and inter-band transitions. We obtain results that can be applied directly to numerical analyses. For simple example of application, we analyze the absorption power and line-widths of ZnO, through the numerical calculation of the theoretical result in the Landau system.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.1
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• pp.24-38
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• 2018

Since a social networking service (SNS) isconsidered as an effective means to communicate and interact with customers, companies are trying to utilize SNS effectively. There is a lack of theory relating to the attributes of SNS. This study aims to investigate the attributes of SNS to classify SNS. Based on the social network theory, and previous studies on internet, blog, homepage, communication attributes, this study proposes the seven attributes to classify SNS: interaction, communication, entertainment, information, sharing, intimacy and connection. A pre-test, a pilot test and a main test are conducted. In the main test, 239 SNS users are participated. Through a factor analysis this study verifies the seven attributes of SNS. An analysis of variance with multiple comparisons of $Scheff{\acute{e}}$ method identifies that three attributes, interaction, communication and connection, are found to play significant roles to differentiate SNS. Looking at the overall mean values of the SNS by attribute, interaction, sharing, entertainment, intimacy and communication were relatively high in Facebook. Facebook showed higher values in attributes of interaction, sharing, entertainment, intimacy and communication. Twitter shows the relatively high scores for information and connection. Regarding interaction, Facebook shows higher scores than Twitter and Cyworld. For connection, Cyworld showed a significantly lower score than Twitter and Facebook. Cyworld was separated from the others in the light of communication. Cyworld is relatively weak in communication as it is limited to the message exchanges. The results will help in identifying major attributes for each SNS and classifying SNS.

• Journal of Digital Convergence
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• v.14 no.3
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• pp.453-464
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• 2016

This study started from the basis of necessity on the researches which asserts that parental rearing behavior in the modern society should change reflecting the social change of sociocultural environment. For this, parental rearing behavior of social constructivism and existing parental rearing behavior were contemplated while construct of parental rearing behavior was explored on the basis of main causes from Vygotsky's theory in order to prepare paradigm of new parental rearing behavior. As far as the method of study goes, various literature from relevant scholars were analyzed, centering various previously conducted studies pertaining to parental rearing behaviors as well as Vygotsky's theory. Also, the validity of the contents was confirmed through consult and revision from three experts. As the result, five factors were extracted. First, factor of cooperative interaction on social interaction. Secondly, emphasis on Internalization factor on social constructive behavior. Thirdly, potential development factor in zone of proximal development. Fourthly, instructional conversation factor as semiotic medium. Lastly, assistance factor as scaffolding. As a result, new paradigm of parental rearing behavior was presented and opened a prospect in developing the touchstone of parental rearing behavior pursuant to social constructivism.

• Journal of the Daesoon Academy of Sciences
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• v.24_2
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• pp.231-270
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• 2015

This thesis examined Chu Hsi's self-cultivation theory as the representative theory of cultivation in Confucianism, while juxtaposing it to self-cultivation theory in Daesoon thought, concentrating on its similarity and difference. Neo-Confucianism is a scholarship which has wielded a tremendous influence upon East Asia, while functioning as an official scholarship for long period up to Yuan, Ming, and Ching period, after achieving its synthesis by Chu Hsi. After 13th century, Neo-Confucianism has been a representative academic system in Confucianism, and self-cultivation theory was in its center. It suggested various virtues that classical scholars have to equip to fulfill the sainthood and the politics of royal road. The self-cultivation theory of Chu Hsi was developed upon the basis of the theory 'Li-Qi' and the theory of mind. Here, the practice of Geokyung(morally awakened state with a reverent spirit in every moment) and Gyeokmul-tsiji(reaching into the utmost knowledge through investigation of things) formed a nucleus of Chu Hsi's self-cultivation theory. While Geokyung was to reveal one's true nature through cultivation of mind, Gyeokmul-tsiji was to demonstrate the complete use of mind's essence and function. Chu Hsi's self-cultivation theory attempted to realize the unity of heaven and man, and through cultivating self and governing people, it also tried to achieve its ideal of the society of Great Union(Daedong). Daesoon Thought is originated from Sangjenim who has descended to this world as a human being called Jeungsan. He went on his circuit to rectify the disorder of heaven and earth for 9 years to rectify the Three worlds of heaven, earth and human being which were faced with total annihilation due to its rule of mutual conflict, while creating an earthly paradise. Respecting the will of Sangjenim, Dojunim established the foundation of Do through launching 'Meukeukdo' and setting tenet, creed and object so that the cultivators (Doins) could believe and respect the truth of Sangje's great itineration (Daesoon). Among those, the two components of creed, which are four fundamental principles and the three fundamental attitudes are of great account as precept and cardinal point. Through this means, the cultivators of Daesoonjinrihoe aspire to guard against self-deception through transforming the human spirit, to realize earthly immortality through renewing human beings, and to create an earthly paradise through transforming the world. This thesis attempted to compare and analyze the theory of self-cultivation in Neo-Confucianism and Daesoon Thought in the aspect of ground, method, and object of cultivation. First, as for the ground of cultivation, the doctrines of Chu-tzu and Daesoon thought place the essence of cultivation on 'heaven'. Yet, whereas the former postulates Taekeuk (the Great Ultimate) as a principle as well as the heaven of a natural order, Daesoon thought postulates Sangenim as the heaven of superintendence as well as the heaven of a natural order, signified as its equation of Daesoon with circle, along with the unity of Meukeuk (Endlessness) and Taegeuk (the Great Ultimate). Further, the doctrine of Chu-zhu and Daesoon thought is identical in the point that both thoughts see mind as the subject of cultivation, while trying to restore a pure essence. Nevertheless, whereas Neo-Confucianism intends to give scope to ability of the complete use of mind's essence and function, Daesoon Thought sees mind as the essence which is used by spiritual beings and as an organ that heaven, earth and human being rely upon as the center of the universe. In the aspect of method of cultivation, the doctrine of Chuzhu lays emphasis on the rational factor in that it brightens its 'myung-deoki'(bright inner virtue),' while trying to correspond to the law of heaven on the basis of 'Geokyung' and 'Gyeokmul-tsiji.' On the contrary, Daesoon thought lays much emphasis on faith factor in that it aspires for human perfection based on the restoration of conscience by cultivating Daesoonjinri with sincerity, reverence and faith along with 'quieting the heart-mind', 'quieting the body', 'respecting the God of the Ninth Heaven', and 'observing ritual practice on the basis of the faith in Sangjenim. Yet, both thoughts have similarities in that cultivation of body forms the basis and that they attempt to realize their ideals through cultivation in daily life while taking 'Guarding against self-deception' as the key method of self-cultivation.' However, the principle of Chu-zhu can be said to be a voluntary and autonomous practice based on scripture of the saint as well as self-reflection. On the other hand, Daesoon thought reveals certain difference in that it combines faith factor with one's self-effort by concentrating on cultivation under the presence of Sangjenim as the object of belief and the spirits of heaven and earth. In the aspect of object of cultivation, both thoughts share similarities in that the saint and the perfected gentleman with a moral virtue as an ideal image of men in both thoughts attempt to realize each of their 'myung-deok' in human nature as a heavenly mandate while respecting morality. Further, they also share similarity in the point that the desirable characters in both thoughts want to participate in harmonious creation and nurturance. Yet, the perfected gentleman with a moral virtue is also characterized by its aim for a new heaven and earth where there is no mutual conflict but mutual beneficence, by promoting the moral influence and virtue of Sangjenim over one's own virtue, while practising the mutual beneficence of all life through harmonious union of divine beings and human beings.