• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.7
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• pp.553-559
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• 2012

A plate-fin heat exchanger is a type of heat exchanger widely used in air conditioners, and tubes and fins are tightly assembled by the mechanical expansion process of tubes. The tube expansion process deforms the grooves inside the tube, and the groove shapes also affect the adhesion between tubes and fins. In this study, the adhesion and heat transfer performance affected by the tube expansion of the non-uniform groove shape tube with different heights are investigated by both analysis and experiments. From the analysis method, it was shown that the contact pressure of non-uniform groove tube is higher than that of the uniform groove tube, and the most appropriate high groove number of the non-uniform groove tube is designed for the maximum contact pressure. From the experimental results, the decreasing rate of the condensation heat transfer coefficient is smaller in the non-uniform groove tube with different heights, compared to the conventional uniform groove tube. Also, the air-side heat transfer coefficient of the non-uniform groove tube with different heights is higher than that of the uniform groove tubes.

• Proceedings of the KIEE Conference
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• 2000.11b
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• pp.361-364
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• 2000

In this study, the system which can make the generator's output voltage more stable by using the inverter in terms of PWM method, is designed It is one of the method reducing velocity of the wind in the process of the wind power generation. Thus, in this system, it is necessary to use a excellent current control inverter. So pulse with modulation method with a high-speed switching element is introduced to control the output current. And also, in order to get a fast response when the standard current generated by the vector control algorithm is supplied with the generator, the output control system with the fast response character and the best current control character is suggested. In this way, the result from the introduction of the control system is that a response character to the changable velocity of the wind is excellent, causing the remarkable reduction of the percentage of the harmonic and the outstanding stability of the variation of the output voltage.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.1
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• pp.35-46
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• 2015

Objective : This study aims to investigate legal and regulatory status of traditional and complementary medicine (T&CM) focusing on regulation on health practitioners and health practice in 33 countries. Method : 33 countries were selected based on several factors such as interest of Korean medical doctors, strategic importance, and distribution over the world. The questionnaire was distributed to Korean embassies in 33 countries in March 2014 through Ministry of Foreign Affairs, and the answers from those countries were collected from April to September. 24 countries that provided sufficient information were included in the analysis. Results : 18 countries have law or regulation on T&CM. Only five countries regulate T&CM practitioners as medical personnel or health practitioner by law, and 12 countries have regulation on license or certificate. Half of 24 countries recognize license of T&CM practitioners issued abroad. There are nine countries that recognize T&CM practice as medical practice, and four of them regulate acupuncture as medical practice by western medical doctors or a few health practitioners recognized by the government. There are six countries that do not recognize T&CM practice as medical practice by law, but regulate it as practice that affect public health, and these countries have law or regulation on T&CM. Conclusion : As T&CM have great impact on public health, many countries have recently legislated law or regulation on T&CM. Rapid change in regulatory status of T&CM affects globalization of Korean medicine. Thus, development of timely strategies will be essential for it.

• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.282-286
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• 1983

In order to obtain practical information for efficient energy usage in sterilization, energy consumption was monitored for various processing variables, i.e. heat transfer type (conduction and convection), can size (No. 202-2, No. 301-3, No. 301-7, and No. 603-2), retorting temperature $(110^{\circ}C-121^{\circ}C\;and\;130^{\circ}C)$, and sterilization method (steam, and hot water sterilization). Less energy was consumed for smaller can size and higher temperature, and this trend was more distinguished in conductive food than convective food. Hot water sterilization could lower energy consumption in conductive food, but not in convective food. Energy consumption data of this work was reasonable when compared with energy consumption of sterilization in canneries, and therefore thought to be able to be used for estimation, design and optimization of energy consumption in sterilization.

• Convergence Security Journal
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• v.15 no.7
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• pp.69-74
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• 2015

Korea has established diplomatic relations with 190 countries in the world. It opened its diplomatic offices in 113 countries. Korea raised its status in international society through multinational force peace activities, national defense cooperation activity and UN peace maintenance activity for the maintenance of world peace. But there have been vio lent crimes by terrorist organizations and armed groups that try to achieve their political, religious and ideological go als greatly damaging Koreans working in overseas countries. This research studied the tendency of international terr orism against Koreans. The suggestion and conclusion are as follows. First, the study shows that armed groups and extremists have threatened and attacked Koreans in overseas countries. But there aren't enough personnel who can i mmediately and correctly analyze and respond the threats and attacks. So it is urgent to raise experts continually an d develop manuals to respond the attacks. Next, the damaging targets in overseas countries have been changed from hard targets to soft targets. There could be a limit in the restriction of basic rights of people by governmental agenc ies. So it is necessary for people to show mature civic awareness not going to a tourism-prohibited area.

• Radiation Oncology Journal
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• v.23 no.4
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• pp.230-235
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• 2005

Purpose: To evaluate the contralateral breast dose using a virtual wedge compared with that using a Physical wedge and an open beam in a Siemens linear accelerator. Materials and Methods: The contralateral breast dose was measured using diodes placed on a humanoid phantom. Diodes were placed at 5.5 cm (position 1), 9.5 cm (position 2), and 14 cm (position 3) along the medial-lateral line from the medial edge of the treatment field. A 6-MV photon beam was used with tangential irradiation technique at 50 and 230 degrees of gantry angle. Asymmetrically collimated $17{\times}10cm$ field was used. for the first set of experiment, four treatment set-ups were used, which were an open medial beam with a 30-degree wedged lateral beam (physical and virtual wedges, respectively) and a 15-degree wedged medial beam with a 15-degree wedged lateral beam (physical and virtual wedges, respectively). The second set of experiment consists of setting with medial beam without wedge, a 15-degree wedge, and a 50-degree wedge (physical and virtual wedges, respectively). Identical monitor units were delivered. Each set of experiment was repeated for three times. Results: In the first set of experiment, the contralateral breast dose was the highest at the position 1 and decreased in order of the position 2 and 3. The contralateral breast dose was reduced with open beam on the medial side ($2.70{\pm}1.46%$) compared to medial beam with a wedge (both physical and virtual) ($3.25{\pm}1.59%$). The differences were larger with a physical wedge ($0.99{\pm}0.18%$) than a virtual wedge ($0.10{\pm}0.01%$) at all positions. The use of a virtual wedge reduced the contralateral breast dose by 0.12% to 1.20% of the proscribed dose compared to a physical wedge with same technique. In the second experiment, the contralateral breast dose decreased in order of the open beam, the virtual wedge, and the physical wedge at the position 1, and it decreased in order of a physical wedge, an open beam, and a virtual wedge at the position 2 and 3. Conclusion: The virtual wedge equipped in a Siemens linear accelerator was found to be useful in reducing dose to the contralateral breast. Our additional finding was that the surface dose distribution from the Siemens accelerator was different from a Varian accelerator.

• Journal of the Korean association of regional geographers
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• v.21 no.2
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• pp.286-303
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• 2015

This paper aims at analyzing the role of Korean ethnic network in the settlement process of Korean immigrants, and elucidating their utilization measures, through the case Study of Korean Immigrants in LA. The main results of this study are as follows. Firstly, the majority of respondents used Korean ethnic networks and Korean town in the immigration process. According to the results of ANOVA test, Korean ethnic network are more importantly considered by the groups such as elderly, livers in Korean town, and people who the first settlement was LA. Secondly, respondents more frequently use Korean ethnic network in the activities such as church, shopping and business. Especially, the groups such as short immigration term, elderly, poor English ability are more frequently use Korean ethnic network. Thirdly, Viewing the cognition of respondents about the necessity of Korean ethnic networks, respondents want to use them for strengthening the ties of domination society. Finally, utilization of Korean ethnic churches, Korean ethnic business organizations and Korean ethnic web-site portal are proposed for activating Korean ethnic networks.

• Journal of Life Science
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• v.26 no.8
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• pp.881-886
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• 2016

Cephalanthera erecta (Thunb. ex, Murray) is an herbaceous and a member of the genus Cephalanthera in the family Orchidaceae. The species is an herbaceous and has reputed Chinese medicinal value. It has been investigated the population density and spatial distribution of this species at Mt. Ahop in Korea during 2015. The spatial pattern of C. erecta was analyzed according to several patchiness indexes, population uniformity or aggregation under different sizes of plots by dispersion indices, and spatial autocorrelation. The mean crowding (M*) and patchiness index (PAI) showed positive values except one small plot (2 m × 2 m). Most natural individuals of C. erecta for plots were not uniformly distributed in the forest community. The small plots (2 m × 2 m, to 8 m × 16 m) of C. erecta were uniformly distributed in the forest community and large plots (16 m × 16 m and 16 m × 32 m) were aggregately distributed. Significant aggregations by Moran's I of C. erecta were partially observed within IV classes (12 m). Dissimilarity among pairs of individuals could found by more than 18.0 m. In conclusion, the geographic distribution of C. erecta is not even with varying degrees of size of plots and human activities give rise to density effects in the plots at Mt. Ahop in Korea.

• Korean Security Journal
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• no.61
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• pp.87-107
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• 2019

With the government policy on converting contract workers to full-time employees, there have been significant changes about the security personnel at the nation's critical facilities, including the National Assembly Building and airports. Moreover, the scheduled disbandment of the conscripted police force in 2023 has raised concerns about security management at different government agencies. To examine the college students' perceptions on the possible alternatives to fill the expected security gap, 234 undergraduate students of security management and protection in the Seoul metropolitan region were surveyed. Particularly, a comparative analysis was conducted on the legal bases and supervision, the employment types and salaries, and the scopes of responsibility and authority of suggested alternatives were compared. The results showed that utilization of private police forces was thought to be the most effective option. Based on the research findings, the university departments should develop and maintain a quality curriculum to educate their students to be prepared security professionals with a focus on emergency response capabilities and martial arts, including the courses on private police law and emergency rescue and cardiopulmonary resuscitation (CPR).

• The Journal of Korean Philosophical History
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• no.58
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• pp.9-33
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• 2018

This article introduce the status and research overview of Korean Confucianism in Eastern Asia with the macroscopic view. Mainly making Tuixi as an example on this basis, respectively make introduction and analysis of research overview among the modern Chinese mainland, Taiwan and Japan towards Korean Confucianism. The scholars who are from Chinese mainland think highly of the expression on meaning and principle in the research of Korean philosophy, which is shown the fair and peace; The scholars who come from Taiwan are obviously impacted by the western world(Taiwan uses the means influenced by the western thinking method) in the means of researching the Korean Confucianism; Japanese persistently rely on the literature and try to reproduce the objectivity of historicism. For decades, the research of Tuixi had made great achievements in Eastern Asia. It had understood the allover content of its thought, It is also worth thinking about the correlation between Tuixi psychology and Yinyang study in Japan, Japan and Taiwan in recent years. Any research is unavoidable to start from own countries, areas and ideological consciousness, but there is a question idea behind the back that comes from emotion and fact. Making the advantage in study meanings and communication in question consciousness will be beneficial to the continuous development of the study of Tuixi in depth and expand its influence.