• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.9
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• pp.878-887
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• 2001

Experimental investigation has been carried out to examine the operating characteristics of a bubble pump for diffusion absorption refrigerator. The effects of heat input and delivery height on generation rate of refrigerant vapor and circulation rate of solution have been investigated. as a result heat input and delivery height increase, circulation rate of solution increases. And the smaller the tube diameter, the larger the circulation rate of solution. Pumping ratio increases to a critical point and then decrease with the increase of heat input, and it increases with the increase in delivery height. In this paper, Marcus's analytical theory was also examined. It was found that the Marcus\`s analytical theory of a bubble pump was not appropriate for a bubble pump using ammonia aqueous solution as a working fluid.

• Journal of applied mathematics & informatics
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• v.26 no.1_2
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• pp.337-347
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• 2008

Based on social welfare maximum theory, the optimal scale of power plants entering generation power market being is researched. A static non-cooperative game model for short-term optimization of power plants with different cost is presented. And the equilibrium solutions and the total social welfare are obtained. According to principle of maximum social welfare selection, the optimization model is solved, optimal number of power plants entering the market is determined. The optimization results can not only increase the customer surplus and improve power production efficiency, but also sustain normal profits of power plants and scale economy of power production, and the waste of resource can also be avoided. At last, case results show that the proposed model is efficient.

• Korean Institute of Interior Design Journal
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• v.23 no.4
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• pp.94-102
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• 2014

Nowadays when the social and cultural paradigm is changing, the incomplete space is becoming a matter of controversy. In order to figure out the solutions to it, are being held a variety of spatial discourses for spatial essence and meaning to be cleared. Accordingly, this study has tried to seek for any probability to interpret the ontology shown at any traditional space on the ground of Heidegger's Ontological Thinking Structure which has a considerable impact on Modern Space, whose conclusions are the followings. First, Heidegger's ontological space theory, which provided a foundation of Placeness concept, includes not only the character of interdisciplinary learning among philosophy, arts and any related studies but also that of mutual oriental and occidental cultures. Second, between the thoughts of Heidegger and Lao-tzu are considerable similarities from the methodical viewpoint that materializes the meaning of existence as an essence. Third, for a convenient interpretation, the ontological spatial concept of Lao-tzu's philosophy shown at traditional spaces have been categorized into Typology-Incident, Morphology-situation and Topology-meaning generation with Schultz's Existential Spatial Concept based on Heidegger's Ontology as a medium. In particular, the meaning generation which materializes the placeness has the trait of being clarified as the product of interactions between incidents and situations.

• Transactions of Materials Processing
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• v.12 no.6
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• pp.572-581
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• 2003

In this paper, an automatic surface construction method based on B-spline surface and scalar field theory is proposed to generate the extrusion die surface of non-symmetric H-and U-shaped sections. The isothermal lines and stream lines designed in the scalar field are introduced to find the control points which are used in constructing B-spline surfaces. Intersected points between the isothermal lines and stream lines are used to construct B-spline surfaces. The inlet and outlet profiles are precisely described with B-spline curves by using the centripetal method for uniform parameterization. The extrusion die surface is generated by using the cubic curve interpolation in the u-and v-directions. A quantitative measure for the control of surface is suggested by introducing the tangential vectors at the inlet and outlet sections. To verify the validity of the proposed method, automatic surface generation is carried out for extrusion die of non-symmetric H-and U-shaped sections.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.997-1007
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• 2021

The last decade has seen the emergence of the idea of "sharing economy" as people are more aware of environmental issues. Although clothing businesses applying the model of sharing consumption have emerged recently, less research effort has been invested in this topic, especially in investigating young consumers' intention. The purpose of this study is to investigate factors driving Generation Z consumers' behavioral intention toward online fashion rental. In this research, a conceptual framework is proposed based on the Theory of Planned Behavior and Technology Acceptance Model. To test the research model and hypotheses, a survey of 375 students and pupils was conducted in Vietnam. All the scales' reliability and validity were assessed through Cronbach's Alpha and confirmatory factor analysis. Structural equation modeling was used to assess the relationship among constructs. The study results showed that attitude toward behavior, subjective norm and perceived behavioral control were positive contributors to Gen Z's intention to use online fashion rental. Besides, the positive relationships between attitude and two other factors - perceived usefulness and perceived ease of use - were also highlighted. Moreover, the findings provided empirical evidence for supporting the positive impact of interpersonal influence, e-WOM, and influencer e-marketing on subjective norm.

• Journal of Korean Medical classics
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• v.31 no.2
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• pp.49-69
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• 2018

Objectives: Following the Jin Yuan Dynasty, the Ming and Song Dynasties witnessed a great development of Yunqi xue. A study into this development has a vast significance in studying the history of the development of traditional Chinese medicine. Methods: The contents relating to Yunqi within the Comprehensive Medical Books, published during the Ming period, and medical texts separately published specifically dealing with Yunqi were used in order to review the unique characters of the study of Yunqi during this period. Results: There were many cases in the comprehensive medical books during the Ming period that dealt with Yunqi. Some of the examples are: Yunqilu in Yixueliuyao, YunQiZongLun in Yixuerumen, and Yunqilu in Yixueliuyao. A number of books that followed suit from the previous generation's study were published, the examples of which are Wangji's Yunqiyilan, and ZhangJiebin's LeiJingtuyi. WangJi, in his book, opposed the mechanic utilization of YunQi theory, and advocated the flexible application of the theory at the doctor's discretion. Liwei, in his YunQiZongLun, wrote a great deal of knowledge which he gained based on the previous-generation medical masters' achievements. Conclusions: Yunqi became widely accepted during the Ming period which led to some doctors advocating the flexible application of the YunQi theory, and some doctors even completely denouncing Yunqi.

• The Journal of Korean Medical History
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• v.13 no.1
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• pp.21-32
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• 2000

Through this research, it was discovered that Wang Sa-wung studied classics such as "Nai Kyung", and brought about new theries and prescription by combining it with his own experience. He asserted 'Ki Hwa Chu Ki' theory which differentiated 'Shin Kam' and 'Bok Sa' within 'On Byung', and this was a new theory which was not in existence before. The main reason for the recognition received by the future generation is, not only because of the substantial theoretical background but, due to the fact that his ideas were based on making practical use easier within rich near a bed experience.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.2
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• pp.131-138
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• 2007

In this paper, a novel nonlinear control method of the CVCF(constant voltage and constant frequency) output voltage for the three-phase PWM inverter with LC output filters is proposed. A nonlinear modeling including the output LC filters is linearized by feedback linearization theory, the controllers of which can be designed based on a linear control theory. It is applied to the DC/AC power conversion of the PWM inverter for stand-alone wind power generation system. It has been verified by the experimental results that the proposed control scheme gives high dynamic responses at load variation as well as a zero steady-state error.

• Transactions of Materials Processing
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• v.13 no.1
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• pp.33-38
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• 2004

A new approach for the design of extrusion die surface of arbitrarily shaped section is presented. In order to generate the extrusion die surface. an automatic surface construction method based on B-spline surface and scalar field theory is proposed. The isothermal lines and stream lines designed in the scalar field are introduced to find the control points which are used in constructing B-spline surfaces. Intersected points between the isothermal lines and stream lines are used to construct B-spline surfaces. The inlet and outlet profiles are precisely described with B-spline curves by using the centripetal method for uniform parameterization. The extrusion die surface is generated by using the cubic curve interpolation in the u- and v-directions. A quantitative measure for the control of surface is suggested by introducing the tangential vectors at the inlet and outlet sections. To verify the validity and effectiveness of the proposed method, automatic surface generation is carried out for extrusion dies of arbitrarily shaped sections.

• Knowledge Management Research
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• v.21 no.2
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• pp.77-100
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• 2020

This study conducted a qualitative study on 23 seniors over 55 years old to understand the digital behavior of seniors in the online education acceptance environment. Grounded Theory methodology was applied to the initial enrollment behavior, login behavior, and utilization behavior of online education program. Through the process of open coding, axis coding, and selective coding, the framework in the online education environment of the senior generation was finally derived. As a causal conditions for the senior generation to participate in the online education environment, goal orientation, relationship orientation, leisure orientation and external compulsory were derived, and shadow work appeared as the central phenomenon. Also, contextual conditions resulted in social change, physical and cognitive aging, and psychological atrophy. The intervening conditions included digital device acceptance, educational attitudes, environmental factors, and self-efficacy. Based on this, the action/interactions strategy formed a positive and negative attitude toward shadow work. As a result, positive response behavior, compromising behavior, and shadow work avoidance behavior were shown. It is hoped that this study will be reflected in future researches for the use of digital devices of the elderly and the expansion of online education participation and government policy.