Evaluation of a Dual-Cooled Annular Fuel Heat Split and Temperature Distribution

YANG, Yong Sik,SHIN, Chang Hwan,CHUN, Tae Hyun,SONG, Kun Woo Atomic Energy Society of Japan 2009 Journal of nuclear science and technology Vol.46 No.8

<P>The heat flux and fuel temperature of an annular fuel rod was analyzed using a newly developed program, DUO_THERM. The dual-cooled annular fuel rod has both inner and outer coolant channels. The heat fluxes to inner and outer claddings can change during irradiation because of the variation in the gap conductances of the inner and outer sides. The heat flux is a very important design factor affecting fuel integrity and safety. However, in an annular fuel design, the prediction of heat flux is very complicated because it is closely connected with size changes of two gaps, which are different from each other during irradiation. A burnup increase and power change can cause pellet and cladding radial deformation and eventually change the gap width. Because an annular fuel has two gaps at both sides and their heat resistances are very large, an imbalance of the gap width can lead to heat flux asymmetry. Therefore, a pellet and cladding dimensional change including densification, swelling, creep, and thermal expansion must be considered in the calculation of heat flux and temperature. By using the DUO_THERM program, the changes in heat flux and temperature during an operation were evaluated with respect to a reference design of an annular fuel. The results of the evaluation showed that the heat flux of an annular fuel was greatly affected by the inner and outer gap conductance changes. The heat flux of the inner cladding was maximum at zero burnup, but that of the outer cladding was maximum at the burnup of the outer gap closing. In addition, the maximum fuel temperature location was changed by gap conductance asymmetry.</P>

상피성 암세포주에 대한 녹차 Catechin의 효과

박정현(Jeong Hyun Park),김대중(Dae Joong Kim),한장희(Jang Hee Hahn),김홍태(Hong Tae Kim),정용욱(Yong Wook Jung),성훈기(Hoon Ki Sung),김주영(Joo Young Kim),송인환(In Hwan Song),성언기(Eon Gi Sung),이융창(Yung Chang Lee) 대한해부학회 2001 Anatomy & Cell Biology Vol.34 No.5

Catechin은 녹차에서 추출되는 폴리페놀의 주요성분으로 고혈압 및 동맥경화의 예방효과, 당뇨억제효과, 항산화작용, 항암작용 등에 직접 관여하는 물질이다. 본 연구에서는 태평양에서 제공받은 녹차 catechin을 이용하여 상피성 암세포주인 A549 (폐암)와 EATC (복수암)세포에 투여한 후 처리농도와 시간에 따른 변화를 비교, 관찰함으로써 녹차의 효과와 작용기전을 밝혀내는데 목적이 있었다. 본실험은 A549 세포와 EATC 세포를 배양한 후 녹차 catechin을 1, 10, 100, 500 μg/ml의 농도로 48시간 동안 처리하였고, 광학현미경, 공초점현미경, 전자현미경 등을 이용하여 세포의 구조적 변화를 확인하였으며 MTT분석, 전기영동, 유세포분석기 등을 사용하여 세포 손상정도를 파악하였다. A549 세포에서는 catechin 1 μg/ml와 10 μg/ml 농도에서는 대조군에 비하여 큰 변화를 관찰할 수 없었다. 100 μg/ml catechin을 처리하였을 때 세포내의 검은 과립들의 수가 증가하였고 층판소체의 손상이 나타났다. 세포주기의 장애가 나타나 DNA 합성전기에 있는 세포들의 수가 급격히 증가하였다. 500 μg/ml 농도에서는 층판소체와 사립체의 파괴가 심하게 나타났으며 세포생존율이 감소하였고 세포주기의 장애도 관찰되었다. EATC 세포에서는 catechin의 농도가 A549 세포의 경우보다 낮은 농도에서도 세포증식 억제 및 세포손상 효과가 나타났다. 10 μg/ml 농도에서도 세포의 위축과 생존율의 감소가 일어났으며 전기영동상에 괴사되는 세포들이 파악되었다. 100μg/ml catechin을 처리하였을 때 자연사의 형태학적 관찰, 전기영동, 유세포분석 등에서 자연사 과정에 있는 세포들이 많이 나타났다. 결과적으로 녹차 catechin을 배양한 상피성 암세포에 투여함으로서 세포의 생존율과 증식이 억제되었고 그 과정에서 괴사, 자연사, 세포주기의 장애 등이 관여하는 것으로 생각된다. 그러나 일련의 세포손상과정을 유도하는 데 있어 세포의 종류, 처리 시간, 농도에 따라 다소 차이가 있음을 확인하였다. Catechin is main component of polyphenol extracts from green tea, it is associated with prevention of hypertension and atherosclerosis, anti-diabetic effect, antioxidant, antitumor. The purpose of this research is to investigate the effect and its mechanism of green tea catechin on epithelial cancer cell lines in various concentrations and durations. For this study, epithelial cancer cell lines, A549 (lung cancer), EATC (Ehrlich-Lettre ascites tumor cell) were used. Inverted, light, confocal and electron microscopes were applied to find morphological changes. MTT assay, flowcytometric analysis, gel electrophoresis were used to compare severity of cellular damages to control after exposure to 1, 10, 100 and 500 μg/ml catechin for 48 hours. In the A549 cells, after 1 μg/ml and 10 μg/ml catechin treatments, there was no notable changes. However, exposure to 100 μg/ml catechin induced increase of cytoplasmic granules, destruction of lamellar body, inhibition of cell cycle, especially G0/G1. In the early phase of 500 μg/ml catechin administration, decrease of cell population, severe destruction of lamellar bodies and mitochondria, derangement of cell cycle were shown. In the EATC, such as those effects occurred after exposure to lower concentration of catechin than in that of A549 cells. After exposure of 10 μg/ml catechin, rounded-up cells and necrotic cells were found. Whereas, most of cells were under apoptotic changes-cytoplasmic condensation, nuclear fragmentation, cellular shrinkage, ladder pattern in the electrophoresis, when administrated 100 μg/ml catechin. These results suggested that exposure of catechin induced severe cellular damage and growth inhibition in dose- and time-dependent manner. And we confirmed that these effects of catechin were involved with apoptosis, necrosis and cell cycle arrest and were quite different according to cancer type. Therefore, much more research would be demanded before clinical application of catechin to human cancer therapy and this study would be the basic source for further study of green tea.

세계의 토양환경 기준에 대한 고찰

송창수,김민환,이원택 호남대학교 산업기술연구소 1998 산업기술연구논문집 Vol.6 No.-

토양오염이란 인간이 제반활동에 의하여 토양 내에 존재하는 특정물질의 농도가 토양의 완충능력이 감당할 수 있는 수준 이상으로 높아져서 인간의 건강이나 주변환경에 피해를 주는 상태로서, 오염된 토양은 자연정화가 어렵고 복원에 많은 시간과 비용이 소요되므로 사전예방적 토양보전관리가 중요하다. 토양환경기준을 설정함에 있어 토양 복원의 목적이 되는 다기능성에 기반을 두어 사전에 오염수치를 설정하는 방안과 지역별로 위해도 평가 및 지역의 복원목적에 맞추어 토양기준을 설정하는 방안으로 나룰 수 있다. 이 두가지 방안을 적용함에 있어서 초기에는 사전 설정된 값을 이용하여, 점차로 의사결정 혹은 많은 복원 비용이 발생하는 경우에 지역별로 위해도 평가를 실시한 후 토양환경 기준을 설정하고 있다. 그러나, 작은 지역에 있어서 위해도 평가라는 추가 비용을 투입하기보다는 자연계 수치까지 복원하는 것이 유리하기 때문에 사전 설정된 값을 토양환경기준으로 설정하고 있다. Soli pollution is often defined in terms of adverse effects on soil frnctions, human health risks and ecological impacts. A few years ago approaches towards contaminated soil classified into "Dutch-list"-approach versus "USA"-approach. The former approach championed the use of predetermined generic criteria and a general cleanup goal(multifunctionality), the latter advocated site specifec risk assessment and site specific cleanup goals. The contrast between these approaches has decreased. All countries tend to use predetermined numerical criteria in the first stages of an assessment and to use site specific assessment methods in later stages of decision making, at least for larger sites and more expensive cleanups. For small sites a cleanup to background values is often less expensive than cleanup based on a site specific risk assessment imcluding additional costs.

성인의 적응장애

송지영,장환일 한국의학사 1986 診斷과治療 Vol.6 No.5

Baculovirus를 이용한 Aujeszky's Disease Virus gⅢ 단백질 발현

송재영,이중복,현방훈,박종현,김병한,권창희,전무형,안수환 충남대학교 생물공학연구소 1993 생물공학연구지 Vol.3 No.-

The g Ⅲ gene located in U_L region of Yangsan strain, a field isolate of Aujeszky's disease virus (ADV) in Korea, was cloned into pTZ18R and sequenced. The gⅢ gene consisting of 1,437 nucleotides showed 98% sequence homology with that of Becker strain, a reference strain of ADV. The gene encoding gⅢ of Yangsan strain was placed under the control of Autographa californica nucleopolyhedrosis virus (AcNPV) polyhedrin promoter, and expressed by the derived recombinant baculovirus using Spodoptera frugiperda 9 (Sf9) cells. The expressed gⅢ was a protein with molecular weight of 72kd determined by immunoprecipitation and Western blotting assay using anti-ADV polyclonal antibodies and anti-gⅢ monoclonal antibody. The partially purified gⅢ protein was utilized as antigen in the radial immunodiffusion enzyme assay (RIDEA) to detect to specific antibody against ADV in pig sera. The results indicated that the sensitivity of RIDEA with the recombinant gⅢ protein antigen (98%) was as high as that with the conventional glycoprotein antigen extracted from the ADV infected cells. In addition, the false positive and false nagative reactions in gⅢ RIDEA were significantly reduced than the conventional glycoprotein RIDEA as judged from the results of standard serum neutralization test.

증기발생기 세관에서 결함 선단 변화에 따른 와전류 결함신호의 분석

송성진,김의래,김창환,김영환 성균관대학교 기계기술연구소 2001 성균관대학교 논문집 기계기술편 Vol.4 No.1

Eddy current signals from flaws with tip variation in steam generator tubes were analyzed. Using finite element models, abundant flaw signals from two dimensional axisymmetric flaws will tip variation were generated. Features of ECT signal were defined and extracted, and sensitive features for flaw classification and sifting were selected. Two neural networks were employed for flaw characterization and sizing. The intercept vector was introduced as a new feature, and its usefulness was discussed.

오염된 토양의 복원을 위한 국내외 제도의 비교 연구

송창수,김민환,이원택 호남대학교 산업기술연구소 1997 산업기술연구논문집 Vol.5 No.-

토양오염은 토양 내에 존재하는 특정한 화학물질의 농도가 높아져서 사람의 건강이나 환경에 피해를 주는 상태로 정의할 수 있다. 오염된 토양은 자연정화가 어렵고 각종 농축산물을 통하여 인체에 위해를 주게되며 원상회복에 많은 시간과 비용이 소모되므로 사후관리보다는 사전예방 차원의 토양보전관리가 중요하다. 국내에서는 1996년도부터 토양환경보전법을 제정, 시행하고 있는데, 여러 측면에서 보완이 필요한 실정이다. 보완이 필요한 것으로 지하수법을 비롯한 환경관련법과의 형평성을 고려하여 토양오염물질을 현행 11개항목에서 순차적으로 확대되어야 한다. 확대의 우선순위는 현행의 중금속 위주에서 유기물질로 전환이 필요하다. 두 번째로, 토양오염의 기준을 현재 및 장래의 토지이용에 기초하여 결정하여야 한다. 세 번째로 현행 법규에서는 토양오염유발시설로 석유 및 유독물질의 저장, 관리시설에 국한하고 있는데, 환경위해성 검토결과에 따라 유발시설에 대한 확대, 관리방안이 마련되어야 한다. General national policies for contaminated land can be very different. Soil pollution is often defined in terms of adverse effects on soil functions, human health risks and ecological impacts. The classic approach based on concentrations of toxic substances exceeding natural background levels or detection limits is used to a lesser extent. In all countries there is a relationship between cleanup and actual or intended land use. In countries where soil cleanup is not closely realted to soil protection at a general policy level, cleanup is directly related to land use. In countries where soil clenaup is a part of a general soil protection policy, thereleationship between land use and cleanup is less direct. Total cleanup, restoring full land use capability(multifunctionality) is the preferred solution in such a policy, only if total cleanup is not feasible a solution is adopted that is dependent on land use.

좌심방에 발생한 원발성 미분류 방추세포 육종 1례

조정환,홍그루,송인욱,손창우,정선영,남종호,김미진 영남대학교 의과대학 2009 Yeungnam University Journal of Medicine Vol.26 No.2

Ethyl loflazepate (Victan^(�))의 항불안효과에 관한 임상적 연구 : OPEN TRIAL

장환일,윤도준,송지영 경희대학교 1989 慶熙醫學 Vol.5 No.2

진동대 모형 실험과 3차원 수치해석을 통한 농업용 저수지의 내진안정성 분석

송창섭, 김명환, 우제근 忠北大學校 農業科學硏究所 2017 農業科學硏究 Vol.33 No.1

The object of this paper was to determine seismic safety of agricultural reservoir. This study was carried out to analysis for the displacement characteristic and seismic acceleration characteristic. This study compare and evaluated the results of shaking table tests and 3-D Numerical analysis. As a result of the shaking table test, acceleration increased 10% after the installation in the short period seismic wave toward the center of levee, The maximum displacement was 11.98 mm in long - term seismic wave, and the permissible shipment variation was corrected to be less than 1% and 220 mm in ‘Assessment and improvement of seismic performance of existing dam’. As a result of 3-D Numerical analysis by combined load of railway vibration load and ground acceleration, the acceleration increased by maximum 2.97 times from bedrock acceleration 0.154 g in short period and long period seismic wave, The displacement was found to be 79.6 mm above the bank in the long - term seismic wave after construction, and the permanent displacement was 11.5 mm in the railway. 3-D Numerical analysis results showed ‘Assessment and improvement of seismic performance of existing dam’ as well as shaking table model test. Further research is needed on the combined action of railway and seismic loads for the seismic stability of agricultural reservoirs.