AN IN-SITU YOUNG'S MODULUS MEASUREMENT TECHNIQUE FOR NUCLEAR POWER PLANTS USING TIME-FREQUENCY ANALYSIS

Choi, Young-Chul,Yoon, Doo-Byung,Park, Jin-Ho,Kwon, Hyun-Sang Korean Nuclear Society 2009 Nuclear Engineering and Technology Vol.41 No.3

Elastic wave is one of the most useful tools for non-destructive tests in nuclear power plants. Since the elastic properties are indispensable for analyzing the behaviors of elastic waves, they should be predetermined within an acceptable accuracy. Nuclear power plants are exposed to harsh environmental conditions and hence the structures are degraded. It means that the Young's modulus becomes unreliable and in-situ measurement of Young's modulus is required from an engineering point of view. Young's modulus is estimated from the group velocity of propagating waves. Because the flexural wave of a plate is inherently dispersive, the group velocity is not clearly evaluated in temporal signal analysis. In order to overcome such ambiguity in estimation of group velocity, Wigner-Ville distribution as the time-frequency analysis technique was proposed and utilized. To verify the proposed method, experiments for steel and acryl plates were performed with accelerometers. The results show good estimation of the Young's modulus of two plates.

AN IN-SITU YOUNG’S MODULUS MEASUREMENT TECHNIQUE FOR NUCLEAR POWER PLANTS USING TIME-FREQUENCY ANALYSIS

YOUNG-CHUL CHOI,DOO-BYUNG YOON,JIN-HO PARK,권휴상 한국원자력학회 2009 Nuclear Engineering and Technology Vol.41 No.3

Elastic wave is one of the most useful tools for non-destructive tests in nuclear power plants. Since the elastic properties are indispensable for analyzing the behaviors of elastic waves, they should be predetermined within an acceptable accuracy. Nuclear power plants are exposed to harsh environmental conditions and hence the structures are degraded. It means that the Young’s modulus becomes unreliable and in-situ measurement of Young’s modulus is required from an engineering point of view. Young’s modulus is estimated from the group velocity of propagating waves. Because the flexural wave of a plate is inherently dispersive, the group velocity is not clearly evaluated in temporal signal analysis. In order to overcome such ambiguity in estimation of group velocity, Wigner-Ville distribution as the time-frequency analysis technique was proposed and utilized. To verify the proposed method, experiments for steel and acryl plates were performed with accelerometers. The results show good estimation of the Young’s modulus of two plates.

가속도계를 이용한 재료의 영계수 측정방법

손창호(Sohn, Chang-Ho),박진호(Park, Jin-Ho),윤두병(Yoon, Doo-Byung),정의필(Chong, Ui-Pil),최영철(Choi, Young-Chul) 한국소음진동공학회 2006 한국소음진동공학회 논문집 Vol.16 No.11

For the description of the elastic properties of linear objects a convenient parameter is the ratio of the stress to the strain, a parameter called the Young's modulus of the material. Young's modulus can be used to predict the elongation or compression of an object as long as the stress is less than the yield strength of the material. Conventional method for estimating Young's modulus measured the ratio of stress to corresponding strain below the proportional limit of a material using a tensile testing machine. But the method needs precision specimens and expensive equipment. In this paper, we proposed method for estimating Young's modulus using accelerometer. The basic idea comes from that the wave velocity is different as the Young's modulus. To obtain Young's modulus, a group velocity is obtained. It is difficult to measure group velocity. This is because plate medium has a dispersive characteristics which has different wave speed as frequency. In this paper, we used Wigner-Ville distribution to measure group velocity. To verify the proposed method, steel and acryl plate experiments have been performed. Experimental results show that the proposed method is powerful for estimating Young's modulus.

성인의 급성 설사에 대한 로페라미드 옥사이드의 효과: 위약과의 무작위 이중 맹검 비교 다시설 시험

박영태,정희진,박중원,이계희,김나영,임선희,윤병철,한동수,이오영 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.31 No.5

생활체육참여자의 여가활동 유형이 생활만족에 미치는 영향

김의영,김의영,김영숙,윤대중,이병기 龍仁大學校 體育科學硏究所 2002 體育科學硏究論叢 Vol.12 No.1

This research is designed to make a comparative analysis of the types of leisure activities and the degree of and life satisfaction by demographic background variable and to present basic materials necessary for the development of programs for local policies on leisure in accordance with the local autonomous system with a view to determining the relationship between life satisfaction by type of leisure activity. The following are the findings. First, the survey failed to test a statistically significant difference between family member's mutual satisfaction, or the subordinate variable of age, job and health and general life satisfaction, or the subordinate variable of income. But there was a statistically significant difference in life satisfaction by gender, age, education, job, income and health at a level of 1 percent. Second, the survey on the influences of the types of leisure activities on leisure satisfaction and life satisfaction revealed that there was a statistically significant influences in all the subordinate variables of and life satisfaction.

부산지역 무균성 뇌막염 원인 바이러스의 분리 및 동정 : 1998년을 중심으로

김영희,정영기,김기순,지영미,윤재득,김병준,구평태,민상기,정구영,김만수,조경순 동의대학교 기초과학연구소 2000 基礎科學硏究論文集 Vol.10 No.1

The incidence of aseptic meningitis infection is ensuing and threatening the health of children. Enteroviruses are the major agents of aseptic meningitis and identification of virus has been a clue to diagnosis and epidemiology. The outbreak of aseptic meningitis occurred in Pusan, 1998. Patients were concentrated from April through November. Children were more susceptible than adults. Among 306 cases of specimens from stool, throat swab tested, only 7.2% were positive on virus isolation, 12 cases from stool and 10 from throat, respectively. All isolated 7 serotypes of viruses represented cytopathic effect on cultured cells. Three types of echovirus 6, 25, 30 and coxsackievirus B2, B3, B4, B6 were identified by neutralizing anti body test. Isolated coxsackievirus and echovirus were observed by an electron microscope with negative staining.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

癩病發病의 年齡의 曆年別 趨勢

任炳昇,崔永燦,金道一 大韓癩學會 1979 癩學 會誌 Vol.12 No.1

영양표시정착화사업(Ⅱ) : 식품참고량설정에 관한 연구 Study on the Establishement of the Reference Amount in Foods

김대병,장영미,김인복,이혜영,장재희,김보영,이정구,김창민,정해랑 식품의약품안전청 2000 식품의약품안전청 연보 Vol.4 No.-

본 연구는 영양표시에서 1회분량 및 영양소함량표시의 기준으로 사용되는 "식픔창고량"에 관한 연구를 수행하므로써 합리적이고 일관성있는 영양표시기준 개선을 위한 기초자료로 활용코자 하였다. 이를 위하여 미국 및 캐나다를 중심으로 제외국의 현황 및 식품참고량 설정방법을 조사 ·연구 하으며 제도도입 및 개선 방안을 강구하였파. 또한, 시판 제품의 영양료시현황 및 음료류 둥의 포장단위 등을 피악하여 식품참고량설정을 위한 기초자료로 활용코자 하였다. 앞으로 국민건강 ·영양조사자료의 체계적인 통계분석, 가공식품의 섭취량조사 등을 통하여 우리나라 국민의 1인 1회 섭취량자료의 축적이 선행되어야 할 것이다. The purpose of this ?roject is to study on the reference amounts customarily consumed per eating occasion to improve the nutrition labelling standards. We Performed to study on the methodology to establish the reference amounts on the basis of the review on the advanced counITy's status. And we investigated the packaged unit ofprocessed foods. Further study is needed to establlsh the customarily consumed amount per eating occasionthrough the statistical analysis of nationwide food consumption data. Our results will be helpful information to improve nutrition labelling system in Korea.

개에서 이중 결찰법을 통한 동맥관 개존증의 완치 예

윤헌영,정순욱,박희명,박철,정만복,김준영,한현정,황민,노병국,박상혁,장하영,박정윤 한국임상수의학회 2004 한국임상수의학회지 Vol.21 No.1

A ten months old, female Yorkshire terrier weighing 2.88 kg referred to veterinary teaching hospital of college of veterinary medicine, Konkuk University because of syncope, cough and dyspnea. First hematological and serum chemical test revealed thrombocytopenia, mild anemia, and increase of concentration of ALP (195 U/L). On 57 days later, second hematological and serum chemical test revealed polycythemia, increase of concentration of ALP (211 U/L), and Tchol (387 mg/dl). Right atrium enlargement, main pulmonary artery bulge and cardiomegaly (VHS = 11.5) were observed in radiographic findings. Ultrasonographic images showed both right and left ventricular dilation and turbulent flow between the descending aorta and the main pulmonary artery in color Doppler imaging. ECG showed left ventricular enlargement, SA block, and electrical alternant. Thoracotomy was performed through left fourth intercostal incision under isoflurane anesthesia. Patent ductus arteriosus was double ligated with 1-0 silk. Cough and dyspnea disappeared on 5 days after operation. Turbulent flow was not found in color doppler imaging of ultrasonography on 10 days after operation. Ten months later after the operation, syncope could not exist any more.