• 인터넷정보학회논문지
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• 제23권3호
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• pp.21-33
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• 2022

본 논문은 기업비밀 노출로 초래될 손실을 현격히 줄일 안전 비밀조각 공유 시스템을 제안한다. 본 연구 시스템은 중앙서버 방식이 아닌 효율적 P2P 분산 시스템을 제안한다. 최근 비트코인 유통 시스템도 역시 P2P 분산 방식을 사용하고 있다. 본 연구는 기능이 단순하고 확장성이 높고 전송 효율적인 토렌트 P2P 분산 구조와 그 프로토콜을 사용하여 토렌트 파일조각 대신 임계 샤미르(Shamir) 비밀조각의 보안 유통을 설계한다. 본 연구는 임계 샤미르 비밀조각 공유기법 (Threshold Shamir Secret Sharing Scheme)을 시스템에 적용하고. 동시에 다중 협동장치의 서명기법을 사용하여 안전하고 강력한 다중인증방식의 사용자 인증을 수행한다. 안전한 비밀 데이터 유통도 공개키로 암호화 교환된 임시키의 대칭암호방식의 효율적 암호화로 전송을 한다. 짧은 유효기간의 임시키는 세션 동안 생성되고 세션 마감후 소멸하므로 키 노출에서 안전하다. 특별히 본 제안한 시스템의 특징은 임계 분산기법을 효율적 토렌트 P2P 분산 시스템에 구조적 변경없이 효과적으로 적용한다. 동시에 본 시스템은 효율적인 임시키 대칭암호방식으로 비밀파일 유통에 기밀성을 보장하고 임시키는 공개키 암호방식으로 안전하게 교환된다, 본 시스템은 외부 유출 기기도 사용자로 동적 등록이 가능하다. 이 확장성으로 기밀성과 인증성을 동적으로 등록된 사용자에게도 적용할 수 있다.

• The Korean Journal of Physiology and Pharmacology
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• 제18권5호
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• pp.411-418
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• 2014

Vascular remodelling is an adaptive mechanism, which counteracts pressure changes in blood circulation. Nicotine content in cigarette increases the risk of hypertension. The exact relationship between nicotine and vascular remodelling still remain unknown. Current study was aimed to determine the effect of clinically relevant dosage of nicotine (equivalent to light smoker) on aortic reactivity, oxidative stress markers and histomorphological changes. Twelve age-matched male Sprague-Dawley rats were randomly divided into two groups, i.e.: normal saline as control or 0.6 mg/kg nicotine for 28 days (i.p., n=6 per group). On day-29, the rats were sacrificed and the thoracic aorta was dissected immediately for further studies. Mean arterial pressure (MAP) and pulse pressure (PP) of nicotine-treated vs. control were significantly increased (p<0.05). Nicotine-treated group showed significant (p<0.05) increase tunica media thickness, and decrease in lumen diameter, suggesting vascular remodelling which lead to prior hypertension state. The phenylephrine (PE)-induced contractile response in nicotine group was significantly higher than control group ($ED_{50}=1.44{\times}10^5M$ vs. $4.9{\times}10^6M$) (p<0.05~0.001). However, nicotine-treated rat showed significantly lower endothelium-dependent relaxation response to acetylcholine (ACh) than in control group ($ED_{50}=6.17{\times}10^7M$ vs. $2.82{\times}10^7M$) (p<0.05), indicating loss of primary vascular function. Malondialdehyde (MDA), a lipid peroxidation marker was significantly higher in nicotine group. Superoxide dismutase (SOD) enzymatic activity and glutathione (GSH) were all reduced in nicotine group (p<0.05) vs. control, suggesting nicotine induces oxidative imbalance. In short, chronic nicotine administration impaired aortic reactivity, probably via redox imbalance and vascular remodelling mechanism.

• 한국지반환경공학회 논문집
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• 제7권3호
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• pp.21-29
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• 2006

난분해성 염색폐수를 처리하기 위한 화학적 처리 방법으로 오존단독처리와 3가지 경우의 고도산화공정[AOPs($O_3/H_2O_2$, $O_3/UV$, $O_3/H_2O_2/UV$)]의 처리특성을 실험적으로 검토하였다. 각각의 처리방법에서 합성 염색폐수를 대상으로 $COD_{cr}$ 및 색도의 제거효율, 생분해도(biodegradability)향상에 대한 처리특성을 상대적으로 비교 평가하였고 pH, 온도, 주입량, 순환유량 등을 주요운전인자로 하여 각 산화공정의 최적운전 조건을 파악하였다. 대상으로 한 모든 공정에서 염색폐수의 색도는 단시간에 대부분 제거되었지만, $COD_{cr}$ 제거측면과 생분해도 향상에서는 $O_3/H_2O_2/UV$ 공정이 가장 좋은 처리효율을 나타냈다.

• 한국초등과학교육학회지:초등과학교육
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• 제36권1호
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• pp.1-15
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• 2017

The purpose of this study is to analyze the problems of land and sea breeze model experiment that has presented in $5^{th}$ grade curriculum in chapter "Weather and our lives" and makes better model simulation so that learners can have better and more effective way to study it. To survey the opinions from dedicated teachers about land and sea breeze model experiment, we produced the survey through interview with science exclusive teacher from M elementary school. An elementary science education expert, 3 men of science EdD modified and complemented survey and started Delphi survey to 12 science teachers who have career teaching more than 3 years. The problems found in this survey were 'one heat bulb, short heating time, small temperature difference of water and sand, lack of class time, empty space between sand and water, back of transparent boxes, little amount of scent and the location of the it' etc. But the most of all, it is hard to see the successful result of the experiment. Based on these kinds of investigations, and lots of trial and error, redesigned the new model experiment that has the most similarity to the real one and high probability of success. According to this, it was able to see the smoke forms horizontal movement along the sand and the smoke goes in one circulation cycle. through this experiment, we made a conclusion that although those scientific experiments in textbook were developed through lots of considerations of expert, to consider the aspect of consumer, it needs to reach the educational agreement about simulation experiment so that It can lead to successful experiment and high quality education.

• 한국실내디자인학회논문집
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• 제11호
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• pp.45-56
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• 1997

In the process of modermization the problem of environment destruction has become a worldwide issue. And now this problem is a concern for all branches of science, including that of architectural desigv. This thesis tries to find the meaning of ecological architectural space, one that encreases the organic relationship, and communication, between architectrual space and urban environmental space, between human beings and architecture, and between human beings and their environment. As an example, we will take a look at the architectural space-design of Frei Otto, who offers diverse creative ecological architectural forms. His concept of architecture has the critical character when compared with the traditionan conventional concept of architecture. The ecological characteristics of his architectural spacedesign can be summarized as follows: The first characteristic is his ample use of natural objects in the architectural structure. An ample use of living things like trees and plants as well as of inanimate thing like water, wind as architectural elements enhances the functional efficiency of architecture. The second characteristic is its ecological architectural system, which saves energy faciliates ventilation by changing the position and direction of the building, by systematically applying the materials, and by efficiently arranging the inner space. The third characteristic is the dematerialization of architecture and the use of materials that are economical and appropriate for the circulation system of nature. The use of natural elements and recycling natural objects, makes it possible to reuse materials of the destroyed building. In short, the ecological architecture of Frei Otto, which shows the relation between human beings and architecture, presents diverse possibilities of the archtectural space as a complex natural system, which is more than a simple combination of separatge elements.

• Journal of Chest Surgery
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• 제12권4호
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• pp.350-354
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• 1979

The incidence of congenital aortic valvular stenosis has been known rare, and approximately 3-6% of congenital heart diseases. Recently, we experienced 1 case of congenital aortic valvular stenosis, and which was corrected surgically under extracorporeal circulation successfully. A 11 years old male pt. was admitted to N.M.C. because of dyspnea, dizziness, chest pain and episode of syncope. An auscultation, harsh systolic murmur [Gr. IV/VI] was noted at aortic area and also palpable strong thrill. ECG showed LVH c strain pattern and suspicious LVH finding in simple chest P-A film. In Lt. cardiac catheterization, abrupt pressure change [110mmHg] between LV & Aorta was noted across the aortic valve. And aortic insufficiency was absent, well visualized both coronary arteries and suspicious bicuspid aortic valve in aortography. Valve form was bicuspid, large one was noncoronary cusp and another cusp was Rt. & Lt. coronary cusp which was interpositioned rudimentary commissure. Central aortic orifice was about 5ram in diameter. Valvulotomy was done along the fusioned commissure between noncoronary cusp and Rt. & Lt.coronary cusp, and then short incision was added between Rt. coronary cusp & Lt. coronary cusp. Immediate postoperative course smooth but unknown cardiac arrest was noted in POD second day. Complete recovery was done without sequelae by resuscitation. After operation, clinical symptoms were subsided but systolic murmur [Gr. II/VI] was audible at aortic area, diastolic murmur was absent. ECG showed still remained LVH but much decreased R wave voltage in Lt. precordial leads. Simple chest P-A showed no interval changes compared to preop film. Control Lt. heart catheterization revealed still remained pressure gradient [40ramrig] between LV & Aorta. But much decreased pressure gradient compared to preop pressure gradient [110mmHg].

• 한국실내디자인학회논문집
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• 제14권1호
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• pp.100-108
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• 2005

If remodeling is defined as activities that restore the overall function of a building up to the standards currently demanded rather than as a simple replacement or repair of old facilities and equipment, the main task of remodeling should be the reduction in differences between areas, establishment of a functional linkage between departments and setup of a smooth circulation system. Therefore, this study is an analysis of remodeling strategies and construction processes to resolve major tasks of remodeling. Through this research we acquire concluding remarks. 1) The remodeling strategies of equipment-intensive areas can be divided into two measures: utilizing the existing buildings (the main buildings) the most, and of concentrated relocation in the new buildings. The former method is advantageous in that the main building serves as a center in hospital layouts because concentrated placement of the diagnosis/ treatment area and the supply area benefit the overall operation in terms of functions. However, the measure has limits in that it is difficult to install the facilities and equipment of the new demands due to the low ceilings, which serve as a potential challenge in future growth and changes. 2) The latter measure is the one in which equipment-intensive areas and the areas that are absolutely short of space are first placed in the new buildings while other areas (the outpatient area, the administration area and the miscellaneous areas) are in the existing building (main building). Given the possibility of development In the future, concentrated placement in the new buildings can be said to be more effective order to actively address future growth and changes.

• 한국비블리아학회지
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• 제15권2호
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• pp.219-240
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• 2004

본 연구는 유비쿼터스 도서관의 실체를 파악하기 위한 연구이다. 이를 위해서 유비쿼터스 컴퓨팅과 유비쿼터스 도서관에 대한 개념적 정의와 함께 그 실태를 파악하기 위하여 유비쿼터스 컴퓨팅에 기반한 유비쿼터스 도서관의 서비스 실태와 과제, 발전 전망 등에 대하여 논의하였다. 문헌연구와 주요 도서관의 홈페이지 내용 분석, 전문사서와의 인터뷰를 통해서 얻어진 결과는 다음과 같다. 첫째, 유비쿼터스 도서관은 무선통신을 이용하여 소장 자료의 검색, 대출 및 반납, 참고질의, 공지사항 등의 서비스를 제공한다. 둘째, 모바일 도서관은 구현 기술의 표준화, 서비스의 단순성, 컨텐츠와 인터페이스의 문제가 제기된다. 셋째, RFID 도서관은 도서관리 프로그램과의 연계성, 시스템의 호환성 및 표준화, 시스템 도입에 따른 도서관 서비스 방식의 변화, 정보 보안과 개인 프라이버시, 시스템 장비의 가격 등이 문제가 된다. 넷째, 유비쿼터스 도서관이 발전하기 위해서는 기술의 통합 및 표준화와 함께 정보기술 인프라와 프로세스의 발전이 이루어져야 한다. 다섯째, 유비쿼터스 도서관의 정보서비스가 성공하기 위해서는 모바일 환경과 특성에 맞는 다양한 형태의 서비스 개발과 함께 개인별 맞춤 서비스가 제공되어야 한다.

• 한국환경과학회지
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• 제5권2호
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• pp.153-170
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• 1996

멕시코 만에서 1987~1988년에 부유 및 칩강입자에 존재하는 광합성 색소 및 그 분해산물은 HPLC를 이용하여 측정하였다. 클로로필과 카로틴계열 및 그 분해산물의 단기 침하율이 Cold-Core Ring 과 Warm-Core Ring에서 비교 분석되었다. 클로로필 a는 CCR과 WCR에서 공통적으로 우세한 포르피린이었으며 카로틴계열 색소 중에는 19'-hwxanoyloxyfucoxanthin이 우세하였다. 초식자의 섭이과정에서 생성되는 것으로 알려진 phaeophobide a가 조사지역 침강입자에 우세하게 나타나는 분해색소 이었따. CCR에서의 전체색소 침하율은 WCR보다 한단게 높게 나타났다. WCR에서 색소현존량은 하루에 1% 이하가 유광밖으로 침하 되었는데 이 사실은 멕시코 만에서 부유고형입자의 재순환은 빠르게 일어나고 있지 않음을 의미한다.

• Ocean and Polar Research
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• 제35권4호
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• pp.415-425
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• 2013

In order to understand phytoplankton and bacterial distribution in tropical coral reef ecosystems in relation to the mangrove community, their biomass and activities were measured in the sea waters of the Chuuk and the Kosrae lagoons located in Micronesia. Chlorophyll a and bacterial abundance showed maximal values in the seawater near the mangrove forests, and then steeply decreased as the distance increased from the mangrove forests, indicating that environmental conditions for these microorganisms changed greatly in lagoon waters. Together with chlorophyll a, abundance of Synechococcus and phototrophic picoeukaryotes and a variety of indicator pigments for dinoflagellates, diatoms, green algae and cryptophytes also showed similar spatial distribution patterns, suggesting that phytoplankton assemblages respond to the environmental gradient by changing community compositions. In addition, primary production and bacterial production were also highest in the bay surrounded by mangrove forest and lowest outside of the lagoon. These results suggest that mangrove waters play an important role in energy production and nutrient cycling in tropical coasts, undoubtedly receiving large inputs of organic matter from shore vegetation such as mangroves. However, the steep decrease of biomass and production of phytoplankton and heterotrophic bacteria within a short distance from the bay to the level of oligotrophic waters indicates that the effect of mangrove waters does not extend far away.