• 한국가시화정보학회지
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• 제17권2호
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• pp.39-47
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• 2019

Impingement cooling utilizing synthetic jets is emerging as a popular cooling technique because of its high local cooling efficiency. The interaction between the vortex structure of the synthetic jet and the surface is crucial in understanding the mechanism of this technique. In this study, the impinging vortex structure and its advection are investigated by experiments with jet-to-surface spacing $2{\leq}H/D{\leq}7$, and synthetic jet Reynolds number $5120{\leq}Re{\leq}9050$. Using phase-locked particle image velocimetry, ensemble averaged (phase averaged) flow fields are obtained, and vortex identification and quantification techniques are applied. The shape, trajectory, and intensity change of the vortex are assessed. A sharp decline in the vortex intensity and the occurrence of a counter-rotating vortex at the impingement point are observed.

• 한국결정성장학회지
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• 제9권6호
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• pp.574-579
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• 1999

암모니아가스를 역류시키는 수평식 유기금속 화학기상증착장치를 제작하였으며, 유체흐름에 관한 레이놀즈 수 및 열대류에 관한 레일리 수가 각각 4.5와 215.8이 되도록 하여 GaN 박막을 성장하였다. 이러한 특성변수에서 박막을 성장할 경우 비교적 양호한 박막의 결정특성, 전기적 특성 및 광학적 특성을 갖게 함을 확인하였다. 결정 내의 전위밀도는 $2.6{\times}10^8/\textrm {cm}^2$ 정도이었고, Si으로 도핑된 n-GaN 박막의 전자에 의한 운반자 농도와 이동도는 각각 $10^{17}$~$10^{18}/{\textrm}{cm}^3$ 과 200~400$\textrm{cm}^2$/V.sec의 범위를 갖으며 Mg을 도핑하여 후속열처리로 활성화시킨 p-GaN 박막은 정공에 의한 운반자 농도가 $8\times 10^{17}/{\textrm}{cm}^3$ 정도임을 확인하였다.

• Strategy21
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• 통권39호
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• pp.163-197
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• 2016

The completion of Jeju Naval Base on February 2016 made the Republic of Korea Navy(ROKN) review the size and role of the Maritime Task Flotilla(MTF). The new strategic environment for the 12st century and the new challenges require the Navy to counter North Korea's provocations and prevent potential enemy's threat. The Navy is also required to take part in the variety of international roles and missions commensurated with Korea's global status to maximize the national interest. Despite these changes, Korea's military construction concept is still unable to break away from the old paradigm of the North Korean threat largely centered. In order to develop the current MTF into the Task Group with the construction of Jeju Naval Base, the Navy must newly not only establish new force development plan and fleet management concepts but also go to persuade and convince policy decision makers. To this end, the following efforts should be promoted. First, the ROK Navy steps up efforts in order to share with the Task Group's vision and strategy. The Navy should also provide the size and structure as well as the missions and roles of the Task Group to react to new maritime security environment. Second, the Navy analyse the MTF's ability and what is required and necessary to perform its duty. After that, it must set out the direction of the Task Group's force development. Third, the current missions and roles of the MTF should be re-established to respond various threats. Finally, accommodating of new technology to the MTF should intensify its strengths. The ROK Navy has a mixed force structure consisting of three fixed- base fleets and a MTF. The fixed base fleet has a passive force to defend and protect its own sea areas, but the MTF should actively not only counter North Korea's threats, including ballistic missiles, but also fight potential threats and takes international missions as a primary task force. However, the MTF has a limited capability to accomplish given missions and long-range operations, and thus, the ROK Navy is strongly required to construct the Task Group.

• 한국재난정보학회 논문집
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• 제5권2호
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• pp.50-73
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• 2009

This paper is about the establishment of "Initial Response System." Initial response system is most important and should be treated urgently among all preparations for chemical terrorism. The objects of Initial response system are to protect civilians and the first responder who are exposed directly to chemical terrorism. Therefore, this paper suggests two main issues about Initial response system. One is to prepare immediate and exact information service system which assures the safety and survival of exposed people. The other is to build Scene Response System integrated with Command-Control Procedure for early finished situation. Compared to United States, overcoming the Chemical Terrorism requires to improve the contents of two categories: Counter Citizen Response part and Initial Scene Response part. For Counter citizen response part' s sake, the web-sites of Response leader agencies for searching information about chemical terrorism should be modified specifically. These web-sites have to be re-organized in detail. The existing Information service system which has been vaguely informed as "CBRNE Accident" needs to be divided as "CBRNE Accident" and "WMD terrorism." Further, each of them should be specialized in "Chemical', "Biological", and "Radiological" categories. There is a need to rearrange current Emergency Instruction for civilians against chemical terrorism in feasible way. At the same time, it should be applied consistently to all organizations through agreement between experts and related-organizations. For Initial Scene Response part's sake, "Initial scene response procedure (SOP)" and "Operational conception" should be produced through Simulated Exercises and workshops of all organizations related with initial response. These organizations have to cooperate with Ministry of Environment which is the main leader Agency as the center. Next, there is a need to develop a technology and Scene Response Equipments, and to standardize the response equipments which consider the capability of First Responders for chemical terrorism. Especially, improving capability of equipments is required to overcome the vulnerability of Scene Response Equipments.

• 대한기계학회논문집B
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• 제25권12호
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• pp.1821-1830
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• 2001

The flow around free end of a finite circular cylinder (FC) embedded in an atmospheric boundary layer has been investigated experimentally. The experiments were carried out in a closed-return type subsonic wind tunnel with varying aspect ratio of the finite cylinder mounted vertically on a flat plate. The wakes behind a 2-D cylinder and a finite cylinder located in a uniform flow were measured for comparison. Reynolds number based on the cylinder diameter was about Re=20,000. A hot-wire anemometer was employed to measure the wake velocity and the mean pressure distributions on the cylinder surface were also measured. The flow past the FC free end shows a complicated three-dimensional wake structure and flow phenomenon is quite different from that of 2-D cylinder. The three-dimensional flow structure was attributed to the downwashing counter rotating vortices separated from the FC free end. As the FC aspect ratio decreases, the vortex shedding frequency decreases and the vortex formation length increases compared to that of 2-D cylinder. Due to the descending counter-rotating twin-vortex, near the FC free end, regular vortex shedding from the cylinder is suppressed and the vortex formation region is hardly distinguished. Around the center of the wake, the mean velocity for the FC located in atmospheric boundary layer has large velocity deficit compared to that of uniform flow.

• 한국콘텐츠학회논문지
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• 제12권2호
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• pp.116-126
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• 2012

영화작가로서 이창동은 장르적 자장 안에서 영화를 만들고 있는 한국영화계의 대다수 감독들과 구별된다. 그동안 그의 영화는 관객과의 소통을 위해 느와르, 멜로 등의 장르를 차용해왔지만 최근작 <시>에 이르러서는 장르적 외피를 벗어던진 것처럼 보인다. <초록물고기>부터 <시>에 이르기까지 일관되게 남은 것은 관객의 참여를 요하는 깊은 심도와 시간의 연속을 암시하는 길게 찍은 숏들의 몽타주, 현실성을 강조한 연기 등 리얼리즘적 표현방식이다. 또한 이창동의 영화들은 환영적 동일시를 깨는 방식으로 관객들에게 성찰의 자리를 돌려준다는 측면에서 장르영화의 카운터 시네마로 파악할 수 있다. 이창동의 영화에서 볼 수 있는 '낯설게 하기'는 핸드헬드, 판타지, 미장아빔, 응시 되돌려 보내기 등의 영화적 장치로 구현된다. 이 장치들은 텍스트의 재현양식을 폭로함으로써 관객들이 역사적, 정치적 컨텍스트를 성찰하게 한다. 본 연구에서는 <시>,<오아시스>,<밀양> 등의 분석을 통해 이창동의 영화 만들기 행위는 결국 보이지 않는 '실재'를 상징화함으로써 '윤리를 창조하는 반복충동'이라고 주장할 것이다.

• 항공우주정책ㆍ법학회지
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• 제21권2호
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• pp.123-155
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• 2006

2001년 미국의 9, 11 항공테러 사건이후에 항공안전 및 보안에 대한 문제점이 지적되면서 이에 대한 효율적인 대책의 필요성이 논의되어왔다. 1950년대 최초 공중납치 사건이 발생한 이후 오늘날에 이르러서는 상당히 다양한 방법으로 항공범죄가 행해지고 있는 가운데 본 논문에서는 전세계 주요국가의 항공보안에 대한 법적 제도적 이슈를 중심으로 변화하는 양상을 체계적으로 정리하였다. 최근 항공테러의 양상과 이에 대한 항공보안의 법적 제도적 발전 형태를 체계적으로 고찰해보고 이에 대한 각국의 항공보안의 법적 제도적 이슈를 비교하여 우리나라에 대한 항공보안의 적용방안을 살펴보았다.

• 성인간호학회지
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• 제18권3호
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• pp.345-356
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• 2006

Purpose: This study was conducted to compare the process of change, decisional balance, and self-efficacy according to the stages of change of exercise on the basis of the Transtheoretical Model in order to investigate factors associated with the change of exercise in adult diabetic patients. Method: Data were collected from January to April 2005. The subjects were 160 patients in the G university hospital and public health center in J city. Results: The entire process of change showed the significant difference depending on the stage of change(F=20.007, p=.000). For each process of change, the Consciousness Raising(F=14.602, p=.000), Dramatic Relief(F=7.751, p=.000), Environmental Re-evaluation(F=11.843, p=.000), Self Re-evaluation(F=16.035, p=.000), Social Liberation(F=10.968, p=.000), Counter-conditioning (F=24.090, p=.000), Helping Relationships(F= 7.625, p=.000), Reinforcement Management(F= 16.693, p=.000), Self Liberation(F=11.990, p= .000) and Stimulus Control(F=4.020, p=.002) demonstrated significant differences depending on the stages of change of exercise. For the decisional balance, the Pros showed the significant difference depending on the stage of change(F=14.121, p=.000). For the self efficacy showed significant difference depending on the stage of change(F=17.137, p=.000). Conclusion: In order to proceed the stage of change of exercise in patients with Diabetes Mellitus, intensive use of a specific process of change, a stage of change matching is needed.

• 한국동물위생학회지
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• 제45권1호
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• pp.39-45
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• 2022

The total bacteria count is significantly important factor for hygienic quality in raw milk. BactoScan FM^TM and BactoCount IBC^TM are the automated instruments for the determination of the total bacterial count in raw milk. They have been used after calibration by standard plate count (SPC) method in South Korea since 2000. It is necessary to re-evaluate for total bacterial counter according to the improvement of milk quality and the change of milk quality grade. Therefore, this study was evaluated the conversion mode of the two machines by SPC method. We collected 921 bulk-tank milk samples throughout the concentration range of 1,000~1,000,000 CFU/mL from June 2020 to October 2021. As a result, when compared by the SPC value, there was a slight difference in total bacterial count in BactoScan below 10,000 CFU/mL and above 200,000 CFU/mL and in BactoCount above 100,000 CFU/mL, respectively. Therefore, the conversion factor for BactoScan and the conversion equation for BactoCount were newly adjusted based on SPC value, and then the correlation coefficients (R²) was 0.85 or higher. In addition, the correlation (R²) between BactoScan and BactoCount was 0.91, which means the results were high positive correlation. These results are expected to contribute to improving the accuracy of the automated instruments for determining of total bacterial count in raw milk.

• 대한한의학방제학회지
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• 제15권1호
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• pp.117-128
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• 2007

We re-classified traditional medicinal prescriptions in Dong-Eui-Bo-Gam for the modern application using Tradimed database. They could be devided into 6 categories by the definitions of the related laws. Herbal ethical drugs are the majority, 3926 items, account for 60.21% of total items. Herbal Health Functional Foods stands second, 1480 items, 22.70%, Herbal over the counter drugs are 893 items, 13.69%. These three categories are about 83% of total items. Herbal medical supplies are 158 items, 2.42%, Herbal medical tools are 44 items, 0.67%, Herbal cosmetics are 20 items, occupied 0.31 %. Therefore we have known that traditional medicinal prescriptions can be used not only as drugs, but also as funtional foods, cosmetics, and tools. So they should be developed as modern products to make best use of them. And we suggested that we need official criteria of herbs of careful use and higher standards for herbs which can be used as foods.