Temperature Dependence of Delayed Hydride Cracking Crack Velocity in Zr-2.5Nb Tubes

Young Suk Kim(김영석) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.11

Delayed hydride crack tests were conducted on Zr-2.5Nb tubes with different distributions of the β-Zr at temperatures ranging from 125 to 300 ℃. Compact tension specimens charged to 27 to 100 ppm hydrogen were used to determine temperature dependences of their DHC velocity (DHCV) and striation spacing. The Zr-2.5Nb tube with a higher yield strength and a seimi-continuous β-Zr has a higher DHCV and a smaller striation spacing than that with a fully discontinuous β-Zr and a lower yield strength. It is found that the activation energy for the DHCV is the sum of the activation energy for hydrogen diffusion and the striation spacing representing the hydrogen concentration gradient at the crack tip. Quantitative contribution of hydrogen diffusion nad the hydrogen concentration gradient to the DHCV is discussed. This study provides supportive evidence to the feasibility of Kim’s DHC model.

여가활동 유형이 여가만족에 미치는 영향

김의영,김의영,김영숙,윤대중,이병기 龍仁大學校 武道硏究所 2002 武道硏究所誌 Vol.13 No.1

This research is designed to make a comparative analysis of the types of leisure activities and the degree of leisure 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 leisure and life satisfaction by type of leisure activity. The following are the findings. First, the survey on testing the difference of leisure satisfaction by gender failed to test the difference in psychological and physiological satisfaction, but there were a statistically significant difference in educational, social and relaxation satisfaction at a level of 1 percent. And the survey failed to test the difference in psychological satisfaction by age, but there was a statistically significant difference in leisure satisfaction by society, education, job, monthly income, and health. Second, the survey on the influences of the types of leisure activities on leisure satisfaction revealed that there was a statistically significant influences in all the subordinate variables of leisure satisfaction.

남자 고등학교 세팍타크로 경기의 공격기술에 관한 분석 연구

김영호,고문석,제임스전,이영익,차정훈,현종건,김범수,임종만,이석인 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.6

This research aims at analysis of attack technique in sepaktakraw games. For this purpose, 3 high school coaches observed and recorded each game Five times in videos of high school male players' thirty games in 2003. The conclusion from the analysis of the recorded data are as follows. 1. Scissors spike was the most popular (favorite) attack technique. Rolling spike, tapping spike and heading spike was popular in order. 2. Heading spike showed the highest success rate (73.5%) in attack technique. And tapping spike (69.5%), scissors spike (57.8%) and rolling spike (67.11) showed a lower success rate in order. In failure rate, heading spike (5.5%), tapping spike (36.5%), scissors spike (32.2%) and rolling spike (32.9%) had a higher percentage in order. 3. When receive was stable, the success rate in attach technique was 47.1%, the failure rate was 20.1%. On the other hand, when receive was unstable, the success rate in attach technique was 16.5%, the failure rate was 14.3%.

호흡기 감염에서 Sparfloxacin 의 임상적 유용성에 대한 Enoxacin과의 비교 검토

김주옥,김선영,김관형,서지원,박석영,이종진,박성학 대한감염학회 1995 감염 Vol.27 No.4

목적:폐렴, 기관지염, 만성기관지염에서 fluoroquinolone제제로서 항균력이 강하고, 혈중 반감기가 길고, 객담과 조직내 농도가 높은 sparfloxacin의 안전성과 효과를 enoxacin과 비교하기 위해 본 연구를 시행 하였다. 방법:1994년 10월부터 1995년 4월까지 충남대 부속병원과 대전 성모병원에 내원한 폐렴, 급성기관지염, 만성기관지염이 급성으로 악화된 환자 63명을 대조군(32명)(enoxacin 100 mg 1일 3회 경구투여), 실험군(31명)(sparfloxacin 200mg 1일 1회 경구투여)으로 나누어 임상증상, 세균학적 객담 검사, 혈액검사, 실험실내 항균력검사로 그 치료율 및 안전성을 비교하였다. 결과: 1) 임상종합 평가, 세균학적 균소실, 안전성, 유용성에서 두군간에 의미 있는 차이는 없었다. 2) 시험관내 항균력검사상 MIC가 실험군이 대조군보다 현저하게 낮았다.(p<0.05). 3) 경미한 두통, 식욕감퇴, 상복부 불쾌감, 설사등이 대조군 9예, 실험군 7예에서 발생하였고, 검사실 소견상 SGOT 혹은 SGPT 의 일시적 경미한 상승이 대조군 2명, 실험군 3명에서, 혈중 creatinine 상승이 실험군 2명에서 있었으나 경미하였다. 결론:이상의 결과로 sparfloxacin은 폐렴, 급성기관지염, 만성기관지염의 악화에서 하루 한번 투여로 enoxacin 하루 3번 투여와 유사하게 효과적이고 안전하며, 시험관내 항균력이 enoxacin보다 월등히 우수하여 임상에서도 유용하게 사용될수 있을것으로 생각된다. Background: Sparfloxacin, a new oral quinolone, has a broad spectrum, potent antimicrobial activity, prolonged half life, high concentration in sputum. The clinical efficacy and safety of sparfloxacin have been reported by some previous clinical studies performed in Japan. The objectives of this study were to evaluate the clinical and antimicrobial efficacy of this drug in respiratory tract infections compared to those of enoxacin. Methods:We performed an open controlled, randomized study in 63 patients with acute bronchitis, pneumonia, and exacerbation of chronic bronchitis at Chung Nam University hospital and Dae Jeon St. Mary's hospital from October, 1994 to April, 1995. In the control group(n=32), 100 mg enoxacin was administered orally 3 times a day and in the test group(n=31), 200 mg sparfloxacin once a day. Results: The results were as follows; 1) There were no significant differences between the two groups in clinical efficacy, bacteriological finding, and usefulness. 2) Means and SD of MICs were 0.44±0.89 ㎍/ml in the control group, 0.13±0.24 ㎍/ml in the test group. There was a significant difference in MICs between the two groups(p<0.05). 3) Headache, epigastric discomfort, and loss of appetite were observed in 7 cases of the control group and in 9 cases of the test group, and transient elevations of hepatic enzyme in 2 cases of the control group, and in 3 cases of the test group. There was mild elevation of serum creatinine in 2 cases of the test group. Those laboratory abnormalities by therapy might be associated with their underlying diseases. There were no significant adverse effects caused by the drugs Conclusion:In conclusion, sparfloxacin of 200 mg once a day was as effective and well tolerated as enoxacin of 100 mg three times per day in the treatment of respiratory tract infections. Sparfloxacin is more potent antibiotics because MICs of sparfloxacin were very lower than those of enoxacin.

전문대학 간호과 통합교과과정 개발에 관한 연구

김영희,김정수,김정애,방숙명,배경진,이애경,장은정,정안순,주미경,최나영 경복대학 1998 京福論叢 Vol.2 No.-

교과과정의 조직은 체계적이고 뜻이 있는 순서로 학생들을 가르치기 위해 지식을 어떻게 조직화할 것인지와, 과목들 사이에서 공통된 내용은 통합시켜 중첩되는 일이 없도록 조정할 필요가 있다. 이에 현재 본 대학 간호과에서 운영되었던 97학년도의 17개 전공과목들의 교과과정의 내용을 비교, 분석하여 중복을 줄이며 순차적 지식의 습득을 도모하는 새로운 통합교과과정의 틀을 개발, 제시함으로써 보다 나은 전문직 간호교육이 이루어지도록 하고자 하였다. Most curricula are considered how to teach the student in systematic and meaningful orders. And it is necessary to coordinate the duplicate contents in major subjects in nursing. So this study was designed to set up a new comprehensive curriculum through comparing and ananlyzing each seventeen major subjects in Nursing Department of Kyung-Bok College. Therefore, the purpose of this study is to present the new comprehensive curricula for promoting the efficiency and effectiveness in diploma degree course of nursing education.

자가 말초혈액 조혈모세포 이식술의 임상적용

김혁,안명주,오석중,이영열,김인순,정태준,최일영,오미란,임호준,이항,김신규 한양대학교 의과대학 1999 한양의대 학술지 Vol.19 No.1

Responses to chemotherapy correlate with the increased dose of chemotherapeutic agents in some cancers, e.g. breast cancer, Ewing's sarcoma, Hodgkin's disease(HD) and non-Hodgkin's lymphoma(NHL), then for the improvement of the chemotherapy responsiveness, high-dose chemotherapy(HDCT) was proposed. But, it's application was limited due to complications, especially bone marrow suppression. HDCT and succeeding autologous peripheral blood stem cell transplantation(APBSCT) was introduced to overcome this problem. This study was designed to determine the clinical pictures including clinical parameters and the responsiveness of HDCT followed by APBSCT in Hanyang University Hospital. Ten patients were enrolled. They were 8 adults (3 breast cancers, 3 multiple myelomas, 1 HD, 1 NHL) and 2 children (1 acute myelogenous leukemia (AML), 1 neuroblastoma). Mobilization chemocherapy(MCT) followed by Granulocyte Colony Stimulating Factor(G-CSF) was administered to mobilize stem cells from bone marrow to peripheral blood. The stem cells were collected by using CS-3000 and cryopreserved at -196℃ with programmed controlled rate freezer as the mixture with 10% dimethyl sulfoxide(DMSO). HDCT was administered and cryopreserved peripheral stem cells were infused on day 0 as planned. Patients' mean age was 41 years old. After induction chemotherapy three patients achieved complete response and 5 partial response. The median time for bone marrow recovery after MCT was 11.5 days for neutrophil(〉500/㎣) and 4.8 days for platelet(〉20,000/㎣). There were three cases of neutropenic fever and one case of gingivitis. After HDCT with APBSCT, one patient was converted partial response to complete response, and one patient achieved complete response after HDCT without induction chemotherapy. The median time for bone marrow recovery was 12.7 days for neutrophil(〉500/㎣) and 14.7 days for platelet(〉20,000/㎣). Eight patients developed neutropenic fever and required systemic antibiotics. Transfusion was required 1.6 pints for packed red cell and 23.4 pints for platelet concentrates. Toxicity consisted mainly of vomiting, diarrhea, and mucositis which were mild. HDCT with APBSCT can be performed safely with minimal complications. For the evaluation of the exact role of HDCT with APBSCT in malignant diseases, further studies are required as a large scale of patients and lung-term follow up.

18–30세 사이에 발생하는 뇌경색의 특징, 다기관 레지스트리 연구

장윤경,송태진,김용재,허지회,이경열,김영은,장민욱,조수진,강석윤 이화여자대학교 의과학연구소 2017 EMJ (Ewha medical journal) Vol.40 No.3

Objectives: Although there have been several reports that described characteristics for young age stroke, information regarding very young age (18–30 years old) has been limited. We aimed to analyze demographic factors, stroke subtype, and 3-month outcome in acute ischemic stroke patient who have relatively very young age in multicenter stroke registry. Methods: We evaluated all 122 (7.1%) consecutive acute ischemic stroke (within 7 days after symptom onset) patients aged 18 to 30 from 17,144 patients who registered in multicenter prospective stroke registry, 1997 to 2012. Etiology was classified by Trial of Org 10172 in Acute Stroke Treatment criteria. Stroke severity was defined as National Institutes of Health Stroke Scale (NIHSS) and stroke outcome was defined by modified Rankin scale (mRS) at 3 months after index stroke. Results: The mean age of all included patients was 25.1±3.7 years and 76 patients (62.2%) were male. The median NIHSS at admission was 4. Considering stroke subtype, 37 patients (30.3%) had stroke of other determined etiology (SOD), 37 (30.3%) had undetermined negative evaluation (UN) and 31 (25.4%) had cardioembolism (CE) were frequently noted. After adjusting age, sex and variables which had P<0.1 in univariable analysis (NIHSS and stroke subtype), CE stroke subtype (odds ratio, 4.68; 95% confidence interval, 1.42–15.48; P=0.011) were significantly associated with poor functional outcome (mRS≥3). Conclusion: In very young age ischemic stroke patients, SOD and UN stroke subtype were most common and CE stroke subtype was independently associated with poor discharge outcome.

노치 형상 및 냉각속도에 따른 Zr-2.5Nb 압력관의 DHC거동

김상재,김영석,임경수,김성수,정용무 대한금속재료학회 2003 대한금속·재료학회지 Vol.41 No.1

The objective of this study is to investigate the delayed hydride cracking (DHC) velocity and the incubation time for the water-quenched and furnace-cooled Zr-2.5Nb tube with the different radius of a notch tip. DHC tests were carried out at constant K_1 of 20 MPa√m and 250℃ on the cantilever beam (CB) specimens subjected to furnace cooling or water quenching after electrolytic charging with 57 or 72 ppm hydrogen, respectively. An acoustic emission sensor was attached to the CB specimens to detect the incubation time before the start of DHC. The shape of the notch tip changed from the fatigue crack to the dull crack with its radius ranging from 0.1 to 0.15 mm. The DHC incubation time increased remarkably with the increasing radius of the notch tip, which appeared more strikingly on the furnace-cooled CB specimens than on the water-quenched ones. However, both furnace-cooled and water-quenched CB specimens indicated little change in the DHC velocity with the radius of the notch tip unless their notch tip exceeded 0.125mm. These results demonstrate that the uncleation rate of hydrides at the notch tip determines the incubation time and the DHC velocity becomes constant after the concentration of hydrogen at the notch tip reaches the terminal solid solubility for dissolution (TSSD). This observation agrees well with Kim's DHC model. A difference in the incubation time and the DHC velocity between the furnace-cooled and water-quenched specimens is discussed in terms of the uncleation rate of hydrides at the notch tip and the hysteresis of hydrogen solubility.

網膜色素上皮細胞의 Lysosomal acid phosphatase의 活性値 測定

김복희,김은경,김윤화,백미화,이지숙,조영숙,황응숙 曉星女子大學校 藥學大學 學生會 1988 曉星藥誌 Vol.4 No.-

Measurement of lysosomal enzyme activity in the rabbit eye was effected using acid phosphatase as enzyme markers. Acid phosphatase in the retinal pigment epithelium of the rabbit eye was studied using standard enzymological techniques. The enzyme activity in the lysosomal extract of the pigment epithelium was 54.9±23.0 King-Armstrong Unit/dl.

Characterization of the isotropic-distortional hardening model and its application to commercially pure titanium sheets

Pham, Quoc Tuan,Lee, Myoung Gyu,Kim, Young Suk Pergamon Press 2019 International journal of mechanical sciences Vol.160 No.-

<P><B>Abstract</B></P> <P>Commercially pure titanium sheets have been widely used in various industrial applications owing to their lightweight nature, superior formability, and excellent corrosion resistance. Previous studies showed that accurate modelling of material characteristics, such as anisotropic yield function and hardening, is essential for the simulation of sheet metal forming with titanium sheets. For example, the non-quadratic anisotropic yield function Yld2000-2d and the modified Kim–Tuan hardening model were used to model initial anisotropy and reproduce flow stress curves at large strains. However, even with these advanced constitutive models for describing the anisotropic behavior of sheet metals, further improvement is necessary to simulate anisotropy evolution, or distortional hardening, in pure titanium sheets. In this study, distortional hardening was experimentally measured under both uniaxial and balanced biaxial loading conditions. Moreover, the evolution of the Yld2000-2d function was modelled as a function of equivalent plastic work. For validation, the developed material models were applied in finite element simulations to analyse deformation behavior in uniaxial tension, hydraulic bulge, and punch-stretching tests. It was confirmed that this approach accurately described material response during these three tests.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Experimental observation of distortional hardening behaviour and three-stage deformation behavior for a pure titanium sheet. </LI> <LI> A procedure to reproduce these material behaviours for the tested material by using an evolutionary yld2000-2d yield function and modified Kim–Tuan hardening law. </LI> <LI> Simulation results of uniaxial tensile tests, hydraulic bulge test, and punch-stretching tests match well with experimental data. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>