• 한국항공우주학회지
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• 제41권3호
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• pp.173-184
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• 2013

본 연구에서는 프로펠러나 헬리콥터 로터와 같은 회전체의 공력 최적 설계를 위한 다단 최적 설계 프레임워크를 제안한다. 이 프레임워크는 플랜폼 설계와 단면의 형상 설계를 반복적으로 수행하는 설계 전략을 통해 회전체의 공력 성능 향상을 목표로 한다. 플랜폼 설계의 단계에서는 유전 알고리즘과 2차원 CFD 데이터베이스 기반의 깃 요소 모멘텀 이론을 이용하여 빠른 시간에 회전체의 공력 특성을 평가하여 최적점을 탐색하였다. 플랜폼 설계 후 단면에 유입되는 유동 조건을 예측하여 단면 형상 최적 설계를 수행하였다. 설계 과정에서 보다 면밀하게 유동 특성이 분석될 수 있도록 2차원 N-S 해석자와 민감도 기반의 최적화 알고리즘을 통해 최적해를 탐색하였다. 단면 형상이 설계된 후에는 최적의 유동 조건을 산출할 수 있도록 플랜폼 설계를 반복적으로 수행하였다. 본 프레임워크를 1kW급 전기추진용 항공기 프로펠러 설계에 적용하여 그 유효성을 3차원 N-S 해석과 풍동 실험을 통해 검증하였다. 설계 후, 풍동 실험 결과를 기준으로 약 5%의 프로펠러 효율 증가를 얻을 수 있었다.

• ALGAE
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• 제29권4호
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• pp.299-310
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• 2014

Dinoflagellates in the genus Symbiodinium are known as zooxanthellae and exist as either symbiotic or free-living forms. Among this genus, two species, Symbiodinium minutum and Symbiodinium psygmophilum, were recently established based on genetic characters. However, some critical morphological characters of these species, such as plate formulae and related diagnoses have not been provided yet. In this study, we analyzed the morphology of S. minutum and S. psygmophilum by scanning and transmission electron microscopy. The S. minutum had the Kofoidian plate formula consisting of a small plate (x), elongated amphiesmal vesicle (EAV), 4', 5a, 8", 7s, two cingulum rows, 18-20c, 6''', and 2'''', while S. psygmophilum had x, EAV, 4', 5a, 8", 7-10s, two cingulum rows, 20-22c, 5-6''', and 1''''. These plate formulae are different from any other reported Symbiodinium species. In addition, both species had a pentagonal 1a plate and a hexagonal 2a plate, while other known Symbiodinium species had a hexagonal 1a plate and a pentagonal 2a plate. Thus, we confirm the species status of S. minutum and S. psygmophilum based on morphological and genetic characters and report the detailed morphological characteristics of these two species.

• 한국전산유체공학회지
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• 제21권2호
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• pp.70-80
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• 2016

The comparison of two commercial codes(FLUENT and STAR-CCM+) and an open-source code(OpenFOAM) are carried out for the aerodynamic analysis of flight vehicles at low speeds. Tailless blended-wing-body UCAV, main wing and propeller of HALE UAV(EAV-3) are chosen as geometries for the investigation. Using the same mesh, incompressible flow simulations are carried out and the results from three different codes are compared. In the linear region, the maximum difference of lift and drag coefficients of UCAV are found to be less than 2% and 5 counts, respectively and shows good agreement with wind tunnel test data. In a stall region, however, the reliability of RANS simulation is found to become poor and the uncertainty according to code also increases. The effect of turbulence models and meshes generated from different tools are also examined. The transition model yields better results in terms of drag which are much closer to the test data. The pitching moment is confirmed to be sensitive to the existence and the location of transition. For the case of EAV-3 wing, the difference of results with ${\kappa}-{\omega}$ SST model is increased when Reynolds number becomes low. The results for the propeller show good agreement within 1% difference of thrust. The reliability and uncertainty of three codes is found to be reasonable for the purpose of engineering use. However, the physical validity and reliability of results seem to be carefully examined when ${\kappa}-{\omega}$ SST model is used for aerodynamic simulation at low speeds or low Reynolds number conditions.

• 한국초지조사료학회지
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• 제20권4호
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• pp.251-258
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• 2000

본 시험은 호주에서 도입된 베치 품종과 우리나라 야생종베치의 생육특성, 사료가치, 및 건물수량을 평가하기 위하여 1998년 8윌부터 1999년 5월까지(1년차)와 1999년 9월부터 2000년 4월까지(2년차) 경북 경산 계명문화대학 실습목장에서 수행되었다. 월동륜은 가을 l차 예취구에서 Haymaker plus, Cappelo 및 Namoi가 각 26, 12 및 3%였고 가을에 예취를 하지 않은 구에서는 Haymaker plus와 Cappelo가 100%였고 Namoi가 70%였으며 Popany 와 Victa는 월동되지 못했다. 2년차 시험에서는 Aneto common을 제외하고 Haymaker plus, Namoi, Cappelo, 자운영 및 야생헤어리베치는 월동이 잘 되었다. 1년차 시험에서 50% 개화기는 Namoi가 4월 23일, Cappelo가 4월 24일, Haymaker plus가 4월 26일 이었다. 2년차 시험에서 50% 개화기는 Namoi와 Cappelo가 4월 12일 Haymaker plus가 4월 14일, 자운영이 4월 23일, Aneto common와 야생헤어리베치가 4월 30일 이었다 l년차 시험에서 건물수량은 Haymaker plus가 가장 높았으며(P<0.05), Cappelo와 Namoi는 Popany와 Victa보다 많았다(P<0.05). 2년차 시험에서는 Namoi, Haymaker plus, Cappelo 및 야생헤어리베치가 자운영이나 Aneto common보다 많았다(P<0.05). 조단백질의 함량은 비교적 높았으며 자운영과 Aneto common은 다른 베치 품종에 비하여 다소 낮았다. ADF 함량도 자운영이 낮았고 다른 베치 품종간에 유사하였다. 따라서 본 시험의 결과에 의하면 가을 파종용 베치 품종은 Haymaker plus를 선택하는 것이 좋을 것으로 생각된다.

• Journal of Acupuncture Research
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• 제19권6호
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• pp.80-96
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• 2002

Objective : The Purpose of this Study is to Evaluate Clinical Effect of Oriental Medical Treatment Clinically for the HNP by Comparing the Improvement of VAS and Meridian MAX Score Gap between Common Acupuncture with Sa-am Acupuncture Treatment Group and Common Acupuncture Treatment Group. Methods : The 29 patients who had a Diagnosis of HNP by Lumbar CT and MRI, and were Observed from the first June 2000 to the tenth May 2001, were divided into two classes ; the "A"group was 14 cases practised with Acupuncture treatment used Sa-am Acupuncture with Common Acupuncture, the "B" group 15 cases only Common Acupuncture. Then the time of Discharge, The authors compared VAS(Visual Analogue Scale) and Meridian Max score Gap out of these two groups. Results : On the result of the VAS(Visual Analog Scale), Group "A" is $4.14{\pm}2.62$ and Group "B" us $2.27{\pm}1.94$. So Group "A" is thought to be significance.(Independent T-test, P=0.0399). On the result of the Meridian Max Score Gap, Group "A" is $2.13{\pm}7.29$ and Group "B" is $1.43{\pm}8.42$. So Group "A" proceed more excellent result than the Group "B" Conclusions : The Group with Sa-am Acupuncture and Common Acupuncture treatment is more effective than the Group With Common Acupuncture treatment. And the Group of Done Cox is more effective than the Group of None.

• 한국초지조사료학회지
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• 제23권4호
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• pp.223-228
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• 2003

본 시험은 대구, 경북 자생치에서 수집된 hairy vetch(Vicia Villosa Roth) 3계통과 자생 woolly pod vetch(Vicia Villosa ssp. dnycarpa (Ten.) Eav) 일본에서 도입된 헤어리베치와 울리포드베치, 호주에서 도입된 울리포드베치인 Haymaker plus 품종의 생육특성 및 건물수량을 평가하기 위하여 2000년 10월 7일에 파종하여 2001년 5월 19일에 수확하였으며 경북 성주 계명문화대학 실습목장에서 수행되었다. 내한성은 일본에서 도입된 울리포드베치와 Haymaker plus가 다른 품종에 비해 다소 약했다. 50% 개화기는 Haymaker plus가 4월 16일, 일본 울리 포드베치가 4월 20일, 자생 헤어리베치(I)가 4월 22일, 자생 헤어리베치(II)가 4월 28일, 자생 헤어리베치(III)가 5월 1일, 자생 울리포드베치가 5월 5일 및 일본 헤어리베치가 5월 10일 이었다. 건물 함량은 Haymaker plus가 가장 높았으며, 50% 개화기가 빠른 품종이 높은 경향이었다. 건물수량은 자생 헤어리베치(III)가 가장 많았으며(P<0.05), 자생 헤어리베치(II)는 다른 품종보다 많았다(P＜0.05). Haymaker plus 및 자생 헤어리베치(I)는 일본 헤어리베치보다 수량이 많았다(P＜0.05).

• 한국한의학연구원논문집
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• 제1권1호
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• pp.159-178
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• 1995

After acupuncture needles were inserted on apkok(LI4) and Kokchi(LI11) accupoints, physiological changes induced by the varitions of 'Qi' were measured. The body temperature and pulse frequency were fromed to be decreased observed and we presumed that the needle insertion induced some changes of Qi in meridian and this seemed to be achieved by a certain process of Qi induction. We applied EAV, nervinemeter and pulse-taking machine which is widely used as oriental medicine instruments, to the same vounteers and observed the significant variations for each apparatus in spite of partial lack of reproducibility. In this paper, we described about the physical quantity measured by the medical appartatus and how it was related to the variation of Qi The proper conditions used for good oriental medicine instruments have also been suggested.

• 한국한의학연구원논문집
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• 제1권1호
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• pp.209-244
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• 1995

The time therapy in oriental medicine is to reserch physiological activity and pathological variation with time, or time with disease. In that, this therapy is to research the development of disease, progress, diagnosis, treatment, and the meaning of preventive medicine. The theory of time therapy has been developed form heaven-human corresponding principle, and fourtimes of seasons is related with human life. After that, this theory affects in yin-yang five circle principle and organ-meridian match system. The independent development was formed later, but the origin has progressed for a logn times. in relation with time therapy, traditional acupuncture therory suggested five semen. In twenty century, the doctor rheinhold voll suggested energy exchange theory, this theory is based on time therapy, but has partial differance also too. His oppinion is this´ the energy present in the body has a circulation following the acupuncture teaching, i.e., the organs and their meridians are flooded in a certain sequence by this flowing energy. This maximum times of the organs are of physiologic and pathologic significance to man. In next time, we will discuss the indivisual theory in detail, and wil have comparison, and considering too.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.772-776
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• 2011

개발 중인 중형 전기추진 무인기는 전력원으로 태양전지, 연료전지, 이차전지를 사용한다. 전력변환기 및 컨버터를 없이 전압 매칭을 통해 전력원을 선정하고 단품시험을 수행하였다. 여러 종류의 전력원을 통합하여 사용함에 따른 각 전력원 별 특성파악 및 에너지 사용 비율을 정량적으로 평가하기 위해 5시간 지상통합시험을 수행하였다. 그 결과 배터리는 시동 및 과도상태에서 다른 동력원에 비해 빠른 출력반응을 보였으며, 연료전지와 태양전지는 순항영역에서 주 전력 공급원의 역할을 수행함을 확인하였다. 사용한 에너지 비율은 연료전지, 태양전지, 배터리가 각각 68%, 29%, 2.5%임을 알 수 있었다.

• 전기학회논문지
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• 제58권2호
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• pp.422-429
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• 2009

Meridian which used as the basic theory of acupuncture treatment, is an important functional connection system of acupuncture point in oriental medicine. Yangdorak and EAV have lack of precision because of using 2-electrode method, occurring high non-uniformed current density and electrode contact status on electrode placement spot. Therefore we implemented a meridian impedance measurement system for measuring meridian impedance using 4-electrode method. In order to confirm the precision of developed system, we made an constant current characteristic experiment using standard resistor. As a results of clinical study with 18 subjects, the meridian impedance showed that reproductivity and repeatability of HT7 acupuncture point are $0.515[k{\Omega}]{\pm}0.000$(mean${\pm}$standard deviation) and $0.515[k{\Omega}]{\pm}0.002$, respectively. And reproductivity and repeatability of PC7 are $0.521[k{\Omega}]{\pm}0.000$ and $0.521[{\Omega}]{\pm}0.001$ respectively. The proposed system was stable and reliable. Therefore this study proved AC impedance method to valid in measuring meridian impedance, and also verified precision and repeatability of the proposed meridian impedance measurement system. The proposed system will serve as more effective method of measuring meridian phenomena as a bioelectric signal in clinical practice.