中學校 科學科의 實驗實習 敎材의 開發硏究(Ⅲ)

尹世重,趙泰璟,吳濟直,金溫植,金黎相 공주대학교 사범대학 과학교육연구소 1983 과학교육연구 Vol.15 No.1

Teaching materials available for the effective performance of laboratory exp-erimental work in middle school were developed: Physics part ; A measuring apparatus of uniformly accelerated motion and normal force of inclined plane was developed. Chemistry part ; An imploved Eudiometer applicable in measuring reaction mole ratio and usful for a gas generating apparatus was developed. Biology part ; convenient teaching materials observing law of dominance, law of segregation, law of independence, incomplete dominance and dihybrid cross were developed. Earth science part ; A laboratory teaching materials observing formation of wave, current and graded bedding, and identification of sedimentary rocks were developed. Putting the above results of study together, the integrated suggestions were made to the effective development of science education in middle school : 1. The contents of science textbook should be simplified to the direction of the understanding of essential principles and concept. 2. The development and dirtrihbution of various supplementary teaching materials (film, T.P., cassettes film, supplementary textbook, program teaching materials individual learning materials) are required. 3. The experimental laboratory should be equipped with common instruments and equipements. 4. Efforts and time are needed to science teachers, and so remission of sundry duties and arrangement of assistant are hopefully considered. 5. Teacher's research activities should be encouraged by administrative route or relevant institute.

우심방과 우심실의 거대 심장 혈관종 1예

김제열,조상호,김건일,허경림,김현숙,조구영,최영진,이원용,임종윤 朝鮮大學校 附設 醫學硏究所 2007 The Medical Journal of Chosun University Vol.32 No.2

Cardiac tumors, especially the primary tumors involving any part of the heart are extremely rare and its relative incidence has been reported to be approximately 0.02%. We report a patient with huge cardiac hemangioma who complained of shortness of breath, general weakness, and dizziness, Imaging study by echocardiography and computed tomography of thorax revealed a huge lobulating mass like a bunch of grapes in the right chamber of heart. The surgical exploration of thorax was performed and a histological diagnosis of spindle cell hemangioma was obtained by microscopy. The patient was treated by surgical resection of the tumor and doing well after surgery. Our experience indicated that prompt diagnosis and treatment of cardiac hemangioma is imperative for patients' prognosis.

연약지반 성토시 사면의 안정에 미치는 Geotextile의 효과

김수일,조삼덕,우제윤 연세대학교 산업기술연구소 1982 논문집 Vol.14 No.2

Geotextiles have been extensively used in road constructions as effective and economical materials performing several functions such as separation, filtration, drainage, protection against frost break, and as reinforcement to improve the load bearing capacity and stability of road. In this study, a method for the analysis of embankment reinforced with geotextile is studied. Computer program based on the simplified Bishop method is modified in order to investigate quantitively the effect of gotextile on the slope stability of embankment on weak soils. Evaluation of the tensile strength required for the design safety factor is also possible utilizing the computer program in this study.

랫드에서 l-muscone의 급성독성 및 아급성독성시험 연구

오승민,연제덕,남혜운,박대규,조명행,정규혁 성균관대학교 약학연구소 1998 成均藥硏論文集 Vol.10 No.1

l-Muscone is synthesized for use as substitutive material of musk which is the active ingredient of woohwangchungsimwon. The objective of this investigation was to evaluate the acute and subacute toxicity of l-muscone in rats. In oral acute toxicity test, SPF Sprague-Dawley male and female rats were gavaged with l-muscone of two doses(0, 5.0g/㎏). No dead animal and abnormal autopsy findings were found in control and treated group. Body weights were slightly decreased in both sexes of rats treated with 5.0g/㎏. Therefore, oral LD_50 of l-muscone was consider to be higher than 5.0g/㎏ in male and female rats. In intraperitoneal acute toxicity test, rats were injected intraperitoneally with dosages of 0, 1,000, 1,316, 1,732, 2,279 and 3,000 ㎎/㎏. Decreased body weights and motor activities were observed at high dose group. Intraperitoneal LD_50 of l-muscone were 1,920 ㎎/㎏ in male and female rats. In the subacute study. l-muscone was administrated orally to both sexes of rats for 4 weeks as several doses(0, 10, 100 and 1,000 ㎎/㎏). There were neither dead animals nor significant changes of body weights during the experimental period. In addition, no differences were found between control and treated groups in clinical signs, urinalysis, hematology, serum biochemical analysis, and other findings. Above data suggest that no observed adverse effect level of l-muscone in rats might be over 1,000 ㎎/㎏/day in this study.

랫드에서 신우황청심원의 급성 및 아급성독성시험

오승민,남혜윤,김준수,연제덕,신대희,이진영,박대규,조명행,정규혁 성균관대학교 약학연구소 1998 成均藥硏論文集 Vol.10 No.1

The acute and subacute toxicity of New Woohwangchungsimwon(NWCH) which was used l-muscone as substitutive material of musk were investigated in S.D. rats. In intraperitoneal acute toxicity test, rats(Sprague-Dawley, SPF) were injected intraperitoneally with dosages of 0, 540, 750, 1,070, 1,500 and 3,000 ㎎/㎏. Body weights were significantly decreased at 540 ㎎/㎏ dose group in both sexes and abnormal autopsy findings were founded in both sexes at all treated groups. Intraperitoneal LD_50 of NWCH was 812.3 ㎎/㎏ in male and 872.3 ㎎/㎏ in female rats. In the subacute toxicity study, NWCH was administrated orally to both sexes of rats for 4 weeks as several doses(0, 320, 800 and 2,000 ㎎/㎏). There were neither dead animals nor significant changes of body weights during the experimental period. In addition, no differences were found between control and treated groups in clinical signs, urinalysis, hematology, serum biochemical analysis, and other findings. Above data strongly suggest that no observed adverse effect level of NWCH might be over 2,000 ㎎/㎏/day in this study.

EXPERIMENTAL STUDY ON MEASUREMENT OF EMISSIVITY FOR ANALYSIS OF SNU-RCCS

CHO YUN-JE,KIM MOON OH,PARK GOON-CHERL Korean Nuclear Society 2006 Nuclear Engineering and Technology Vol.38 No.1

SNU-RCCS is a water pool type RCCS (Reactor Cavity Cooling System) developed for VHTR (Very High Temperature Reactor) application by SNU (Seoul National University). Since radiation heat transfer is the major process of passive heat removal in a RCCS, it is important to determine the precise emissivity of the reactor vessel. Review studies have used a constant emissivity in the passive heat removal analysis, even though the emissivity depends on many factors such as temperature, surface roughness, oxidation level, wavelength, direction, atmosphere conditions, etc. Therefore, information on the emissivity of a given material in a real RCCS is essential in order to properly analyze the radiation heat transfer in a VHTR. The objectives of this study are to develop a method for compensation of the factors affecting the emissivity measurement using an infrared thermometer and to estimate the true emissivity from the measured emissivity via the developed method, especially in the SNU-RCCS environment. From this viewpoint, we investigated factors such as the attenuation effect of the window, filling gas, and the effect of background radiation on the emissivity measurements. The emissivity of the vessel surface of the SNU-RCCS facility was then measured using a sight tube. The background radiation was subsequently removed from the measured emissivity by solving a simultaneous equation. Finally, the calculated emissivity was compared with the measured emissivity in a separate emissivity measurement device, yielding good agreement with the emissivity increase with vessel temperature in a range of 0.82 to 0.88.

Structural Biology and Drug Targeting : Structure of the Mus81-Emel complex provides insights into rescuing stalled replication forks

( Yun Je Cho ) 한국생화학분자생물학회 (구 한국생화학회) 2008 생화학분자생물학회 춘계학술발표논문집 Vol.2008 No.-

Non-hypervascular Hypointense Nodules on Hepatocyte Phase Gadoxetic Acid-Enhanced MR Images: Transformation of MR Hepatobiliary Hypointense Nodules into Hypervascular Hepatocellular Carcinomas

( Yun Ku Cho ),( Ju Won Kim ),( Mi Young Kim ),( Hyeon Je Cho ) 대한간학회 2018 Gut and Liver Vol.12 No.1

Background/Aims: The annual risk of transformation of non-hypervascular magnetic resonance (MR) hepatobiliary phase imaging (HBPI) hypointense nodules into hypervascular hepatocellular carcinomas (HCCs) was evaluated. Methods: Cirrhotic patients with non-hypervascular HBPI hypointense nodules were retrospectively analyzed if they were diagnosed as HCC and MR followed up longer than 1 year during the period from January 2010 to October 2016 with regular intervals of 3 to 6 months. Risk factors for transformation into hypervascular HCCs were analyzed using the Cox proportional hazard model. Results: Among the 103 non-hypervascular HBPI hypointense nodules meeting the inclusion criteria, transformation into hypervascular HCCs occurred in 44 tumors (42.7%). The median follow-up period was 24 months. Multivariate analysis revealed that hyperintensity on T2-weighted images (T2WI) and diffusion-weighted images (DWI) were the two independent predictors of transformation into hypervascular HCCs (p=0.036 and p=0.041, respectively). Most tumors with hyperintensity on T2WI or DWI on the initial or follow-up MR were transformed into hypervascular HCCs within the first year. Among the 22 nodules (21.3%) showing a new change in dynamic phases during follow-up, 14 nodules (13.6%) showed malignant transformations. Conclusions: The transformation rates of HBPI hypointense nodules into hypervascular HCCs could be predicted according to the initial or serial MRI findings. (Gut Liver 2018;12:79-85)

Construction of Stably Transformed Bm 5 Cells by Using Autographa californica Nuclear Polyhedrosis Virus IE 0 Gene

Cho, Eun Sook,Jin, Byung Rae,Sohn, Hung Dae,Choi, Kwang Ho,Kim, Soung Ryul,Kang, Seok Woo,Yun, Eun Young,Kim, Sang Hyun,Kim, Keun Young,Je, Yeon Ho,Kang, Seok Kwon 한국잠사학회 1998 한국잠사곤충학회지 Vol.40 No.2

To construct transfurmed Bm5 cells, Autographa californica nuclear polyhedrosis virus(AcNPV) IE1 gene, an immediate early viral gene was firstly used in this study. AcNPV IE1 gene, which shares on 95.3% nucleotide sequence homology with Bombyx mori nuclear polyhedrosis virus (BmNPV) IE1 gene, was isolated and cloned into pBluescript. Neomycin gene from pKO-neo was inserted under the control of the IE1 promoter to yield pAcIE1-neo. The plasmid pAcIE1-neo was transfected into Bm5 or Sf9 cells, and neomycin-resistant cells were selected in TC100 medium containing 10% fetal bovine serum (FBS) and 1 mg/ml G4l8 for two weeks. Individual clones were picked and each was amplified for further characterization. The genomic DNA from neomycin-resistant cells was isolated and characterized by PCR using AcNPV IEI gene-specific primers and by Southern blot analysis using neomycin gene probe. We concluded that AcNPV IE1 gene was functional in B. mori-derived Bm5 cells as well as Spodoptera fugjprrda-derived Sf9 cells to produce stably-transformed insect cells

ASSESSMENT OF CONDENSATION HEAT TRANSFER MODEL TO EVALUATE PERFORMANCE OF THE PASSIVE AUXILIARY FEEDWATER SYSTEM

Cho, Yun-Je,Kim, Seok,Bae, Byoung-Uhn,Park, Yusun,Kang, Kyoung-Ho,Yun, Byong-Jo Korean Nuclear Society 2013 Nuclear Engineering and Technology Vol.45 No.6

As passive safety features for nuclear power plants receive increasing attention, various studies have been conducted to develop safety systems for 3rd-generation (GEN-III) nuclear power plants that are driven by passive systems. The Passive Auxiliary Feedwater System (PAFS) is one of several passive safety systems being designed for the Advanced Power Reactor Plus (APR+), and extensive studies are being conducted to complete its design and to verify its feasibility. Because the PAFS removes decay heat from the reactor core under transient and accident conditions, it is necessary to evaluate the heat removal capability of the PAFS under hypothetical accident conditions. The heat removal capability of the PAFS is strongly dependent on the heat transfer at the condensate tube in Passive Condensation Heat Exchanger (PCHX). To evaluate the model of heat transfer coefficient for condensation, the Multi-dimensional Analysis of Reactor Safety (MARS) code is used to simulate the experimental results from PAFS Condensing Heat Removal Assessment Loop (PASCAL). The Shah model, a default model for condensation heat transfer coefficient in the MARS code, under-predicts the experimental data from the PASCAL. To improve the calculation result, The Thome model and the new version of the Shah model are implemented and compared with the experimental data.