A Study on Output Characteristics of Wave Energy Conversion System combined with Breakwater depending on Geometry of Seawater Entrance Section

This paper deals with the characteristics of wave energy conversion system combined with breakwater including an air-driven wells turbine and cross-flow water turbine. The wave energy converter with Oscillating Water Column(OWC) has mostly been studied to raise energy conversion efficiency. The aim of this research is to verify the effectiveness of curved seawater entrance section of OWC chamber through both numerical simulation using LabVIEW and scale model experiment in the 2-D wave tank. Incident wave was assumed as sinusoidal, and other minor losses except for entrance loss were ignored, and also cavity resonance wasn't considered in the simulation. The simulation was conducted at 2.0sec in wave period and 0.13m in wave height. And 5 different entrance loss coefficients were used as parameters:0.01,0.02,0.1,0.5. The simulation result which contains the velocity of free-water surface, the vertical displacement of water and the available energy to the turbine shows that the effect of entrance loss coefficient is not significant under the assumptions as mentioned above. Scale model with 4 different types of entrance section was used in the experiment. The model contains a cross-flow water turbine and a wells turbine. Experimental conditions were almost same as numerical simulation at 2.0sec in wave period, 0.13m in wave height, 0.7m in depth of water. Turbine RPM, output voltage from DC generator, water level in the OWC chamber and air pressure under the wells turbine were measured by CompactRIO system based on LabVIEW. The most obvious difference found in the experimental results depending on the geometry was a hydrodynamic performance from cross-flow water turbine: it was about 25%. Through the model experiment, it can be inferred that an elliptic curved surface whose horizontal distance is longer than vertical distance can improve wave energy conversion efficiency by reducing head loss in the fixed OWC chamber. The experimental results provide a blueprint for the inlet geometry design of wave energy conversion system combined with breakwater.Nomenclatures ⅲ List of tables ⅵ List of figures ⅶ Abstract ⅹ 제 1 장 서 론 1 1.1 연구 배경 1 1.2 연구 동향 2 1.3 연구 내용 및 구성 3 제 2 장 파력발전시스템 4 2.1 파랑에너지 4 2.1.1 파랑의 특성 4 2.1.2 수심에 따른 파랑의 분류 5 2.2 방파제 부착형 파력발전시스템 구성 8 2.2.1 진동수주 챔버 9 2.2.2 공기터빈 10 2.2.3 횡류터빈 11 2.2.4 해수유입구 형상 12 제 3 장 시뮬레이션 13 3.1 개요 13 3.2 수학적 모델링 14 3.3 프로그램 구성 18 3.4 시뮬레이션 결과 20 제 4 장 방파제 부착형 파력발전 모형실험 22 4.1 실험조건 22 4.2 모형실험 장치 23 4.2.1 조파수조 23 4.2.2 방파제 부착형 파력발전 모형 23 4.2.3 데이터수집 장치 27 4.3 데이터분석 프로그램 33 제 5 장 실험 및 고찰 42 5.1 웰즈터빈과 횡류터빈의 회전속도 42 5.2 발전기 출력 전압 46 5.3 진동수주 내부 수위변화 50 5.4 웰즈터빈 입구의 공기 속도 53 5.5 진동수주 내부 자유수면의 속도 56 제 6 장 결 론 59 참 고 문 헌 6

Experimental Study on Performance of Wave Energy Converter System with Counter-Weight

Movable body type wave energy converter system with counter-weight converts energy from heave motion of buoy to rotatory power. Measuring rotatory power is conducted to evaluate the energy conversion efficiency of wave energy converter, which is installed on 2-dimensional ocean generating basin with power take-off system composed torque sensor and brake. At the same time, this study analyzes performance of energy conversion according to wave height and weight condition of both flywheel and counter-weight by changing load torque and wave period. Therefore, this research is able to be useful basic material such as optimal design of movable body type wave energy converter and improving its energy conversion efficiency as well.List of Tables List of Figures Abstract 1. 서론 1.1 연구배경 1.2 기존연구 1.3 연구내용 2. 카운터웨이트 파력발전시스템 2.1 파력발전시스템 구성 2.2 파력발전시스템 원리 3. 실험방법 및 모형 3.1 실험조건 3.2 모형 3.3 실험장치 및 방법 3.4 데이터 계측 및 처리방법 4. 연구 결과 및 고찰 4.1 카운터웨이트의 영향 4.2 플라이휠의 영향 4.3 파고의 영향 4.4 Capture Width Ratio 4.5 고찰 5. 결론 및 향후과제 5.1 결론 5.2 향후과제 Reference Bibliography 감사의

(An) experimental study on the forensic odontological method in identification of death by drowning : studies on intrusion of water into pulp tissue

치의학과/석사[한글] 익수에는 특정지역에 특이한 유기질 또는 광물질이 (현탁액 또는 용액상으로)포함될 수 있다. 따라서, 조류, 규조류, 모래, 진흙 그리고 분해물질까지도 익사의 장소를 지적하는데 사용될 수 있다. 익사체에는 말단폐부종이 있어, 단백질과 익수가 폐순환을 떠나 폐포속으로 들어가게 된다. Swann의 실험 (deuterium oxide를 추적자로 사용한)은, 익사체에서는 익사의 과정중에 익수가 대순환계를 출입항율 시사하고 있다. 반면, 교살한 토끼를 분쇄규조의 짙은 현탁액이 포함된 익수에 투수한, Crosfill과 Holden의 조사는 이러한 물질들이 페포강내에 존 재함을 보여주었다( 3마리의 토끼중 2마리에서). 이러한 결과로 볼 때, 익사체로서 발견된 시체의 폐포내에 이종의 입자가 있다는 소견은 생시에 투수되었다고 증명하기엔 만족스럽지 못하다. 이러한 문제점을 제거하기 위해 저자는 해부학적 구조가 특이한 개의 치수를 선택하여, 다음의 성적을 얻었다. 1 .실험규조수 내에서 익사시킨 예에서의 치수내 규조립의 분포를 조사하였다. 2. 교살후 규조수 내에 투수한 예에서는 치수내 규조립을 볼 수 없었다. 3. Gentiana Violet용액으로써는 익사판단이 불가능할 정도로 소량의 익수만이 침투됨이 추정된다. An Experimental Study on the Forensic Odontological Method in Identification of Death by Drowning - Studies on Intrusion of Water into Pulp Tissue- SUNG HOON HAN, D.D.S. Dept of Dental Science, The Graduate School, Yonsei University (Directed by Assistant Professor : Chong Youl Kim, D.D.S. M.S.D., Ph. D.) Drowning media may contain organic or mineral matter(in suspension or solution) which are characteristic of a particular locality or source. Thus algae diatoms, sand,mud, and even dissolved matter, may be used to indicate the palce where drowning has cooerred. In drowning there is a terminal pulmonary oedema in which both protein and fluids leave the pulmonray circulation and enter the alveoli. Swann;s experiment (using deuterium oxide as a tracer) show that water leaves and enters the circulation during the drowning process in drowning . On the other hand, Crosfill and Holden's investigations on rabbits, immersed after death water containing a dense suspension of crush diatoms, have shown the presence of these bodies in the alveolar spaces (two our of three rabbits). In the view of this results, it appears that the finding of foreign particles in the alveolae of the lung of a body found drowned cannot be regarded as satisfactory proof that immersion had occurred during life. So as to get rid of the above problem, the author selected dental pulp tissue of dog, specially structured anatomically, and obtained the following results. 1. In the case of drowning in water containing a dense sespension of crush diatoms, the distribution of diatoms in the pulp tissue was studied. 2. In the cases of experimental animals which were strangulated first and then thrown into water, the distribution of diatoms in the pulp tissue was not observed. 3. It was very hard to determine drowning by Gentiana Violet solution. [영문] Drowning media may contain organic or mineral matter(in suspension or solution) which are characteristic of a particular locality or source. Thus algae diatoms, sand,mud, and even dissolved matter, may be used to indicate the palce where drowning has cooerred. In drowning there is a terminal pulmonary oedema in which both protein and fluids leave the pulmonray circulation and enter the alveoli. Swann;s experiment (using deuterium oxide as a tracer) show that water leaves and enters the circulation during the drowning process in drowning . On the other hand, Crosfill and Holden's investigations on rabbits, immersed after death water containing a dense suspension of crush diatoms, have shown the presence of these bodies in the alveolar spaces (two our of three rabbits). In the view of this results, it appears that the finding of foreign particles in the alveolae of the lung of a body found drowned cannot be regarded as satisfactory proof that immersion had occurred during life. So as to get rid of the above problem, the author selected dental pulp tissue of dog, specially structured anatomically, and obtained the following results. 1. In the case of drowning in water containing a dense sespension of crush diatoms, the distribution of diatoms in the pulp tissue was studied. 2. In the cases of experimental animals which were strangulated first and then thrown into water, the distribution of diatoms in the pulp tissue was not observed. 3. It was very hard to determine drowning by Gentiana Violet solution.restrictio

Experimental studies on the effect of cariogenic diet and salivation on the dental caries in albino rats

치의학과/박사[한글] 치아우식증의 발생원인과 기전 및 예방관리의 원리를 구명하려는 많은 노력의 결과 여러 가지 복잡한 인자들이 관여함이 밝혀졌으며 그 중에서도 식이의 성분 및 세균의 역할이 중요함이 인지되었다. 그러나 아직껏 밝혀지지 않은 부분이 많아 실험동물에 의한 치아우식 발생에 관한 연구가 계속 보고되어 오고 있다. 치아우식 발생에 관한 연구를 함에 있어 실험동물로서는 백서가 가장 적합함이 알려진 바 있어 저자는 연세대학교 의과대학 동물실에서 사육하고 있는 생후 21∼25일의 체중 40gm내외의 자성 백서 60두에 우식성식이와 타액분비에 영향을 미치는 약제를 투여하며 90일간 사육한 후 우식 발생의 양상을 검토하여 다음과 같은 결론을 얻었다. 제1군 : balanced diet+water 제2군 : balanced diet+pilocarpine water 제3군 : balanced dist+atropine water 제4군 : cariogenic diet+water 제5군 : cariogenic diet+pilocarpine water 제6군 : cariogcnic diet+atropine water 1. cariogenic diet 군들이 balanced diet 군들에 비하여 성장이 극히 저조하였으며 타액분비가 성장에 미치는 영향은 별로 관찰되지 않았다. 2. 치아우식발생이 6군> 4군> 5군> 3군> 1군> 2군의 순서로서 식이가 우식발생에 미치는 영향이 크며 타액분비도 치아우식발생과 밀접한 관계가 있음이 확인되었다. 3. 상하악간의 우식발생은 하악이 상악보다 다소 높은 것으로 나타났다. 4. 백서우식관찰연구에 위상차 현미경 관찰에 의한 major sulcal scoring이 권장할만하다. EXPERIMENTAL STUDIES ON THE EFFECT OF CARI0GENIC DIET AND SALIVATION ON THE DENTAL CARIES IN ALBINO RATS Sung-Hoon, Han. D.D.S.,M.S.D. Dept. of Dental Science, Graduate School, Yonsei Univ. (Directed by prof. Chong-you, Kim.D.D.S., M.S.D., Ph.D.) The author had divided the sixty female weaning albino rats from Yonsei University-Animal House into following 6 groups and the rats were fed for 90 days. Group 1 : balanced diet + water Group 2 : balanced diet + pilocarpine water Group 3 : balanced diet + atropine water Group 4 : cariogenic diet + water Group 5 : cariogenic diet + pilocarpine water Group 6 : cariogenic diet + atropine water At this time, the animals were sacrified and the induced dental caries had been observed according to the caries rate, the carious teeth index and caries score by Keyes'method. The results were as followings; 1. The average gain of body weight in cariogenic diet groups was much less than that of in balanced diet groups. 2. The dental caries susceptibility order was as follows, group 6> group 4> group 5> group 3>, group 1> group 2. This shows influence to dental caries susceptibility of diet was very significant and the influence of salivary flow was significant too. 3. The caries scores of lower molars were somewhat higher than the scores of upper molars. 4. The method by phase difference microscope were recommendable for major sulcal scoring for experimental dental caries study of rats. [영문] The author had divided the sixty female weaning albino rats from Yonsei University-Animal House into following 6 groups and the rats were fed for 90 days. Group 1 : balanced diet + water Group 2 : balanced diet + pilocarpine water Group 3 : balanced diet + atropine water Group 4 : cariogenic diet + water Group 5 : cariogenic diet + pilocarpine water Group 6 : cariogenic diet + atropine water At this time, the animals were sacrified and the induced dental caries had been observed according to the caries rate, the carious teeth index and caries score by Keyes'method. The results were as followings; 1. The average gain of body weight in cariogenic diet groups was much less than that of in balanced diet groups. 2. The dental caries susceptibility order was as follows, group 6> group 4> group 5> group 3>, group 1> group 2. This shows influence to dental caries susceptibility of diet was very significant and the influence of salivary flow was significant too. 3. The caries scores of lower molars were somewhat higher than the scores of upper molars. 4. The method by phase difference microscope were recommendable for major sulcal scoring for experimental dental caries study of rats.restrictio