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.

신경회로망에 의한 용접 결함 종류의 정량적인 자동인식 시스템 개발에 관한 연구

김재열,김영석,김병현,유신,김훈조,정진홍 한국공작기계학회 1997 한국생산제조학회지 Vol.6 No.1

A neural network approach has been developed to determine the depth of a surface breaking crack in a steel plate from ultrasonic backscattering data. The network is trained by the use of feedforward three-layered network together with a back-scattering algorithm for error correction. The signal used for crack insonification is a mode converted 70˚ transverse wave. A numerical analysis of back scattered field is carried out based on elastic wave theory, by the use of the boundary element method. The numerical data are calibrated by comparison with experimental data. The numerical analysis provides synthetic data for the training of the network. The training data have been calculated for cracks with specified increments of the crack depth. The performance of the network has been tested on other synthetic data and experimental data which are different form the training data.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1994)

김재홍,안진균,정성재,김영태,김중환,김시영,이석종,이홍렬,서호석,김경훈,권혁진,정우권,고우석,이용석,안필수,오준규,오용섭 대한화학요법학회 1996 대한화학요법학회지 Vol.14 No.1

Background : In recent years gonorrhoea has been panendemic and remains one of the most common Sexually Transmitted Diseases in the world, especially in developing countries. Objective & Method : For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria Gonorrhoeae(PPNG), Ive have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results : In 1994, 168 strains of N. gonorrhoeae were isolated, among which 109 (64,9% ) were PPNG. Conclustion : Our results suggests that the prevalence of PPNG in Seoul is still increasing.

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.

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.

Students’ Perspectives on Pre-recorded Video Lectures Versus Video-Conferencing Lectures in the Untact Era

Kim,Hea-Suk,Cha,Yoonjung,Kim,Na-Young 이화여자대학교 교과교육연구소 2021 교과교육학연구 Vol.25 No.2

The purpose of this study is to examine students’ perspectives on two online learning formats: pre-recorded video lectures versus video-conferencing. There were 90 participants who took College English courses in a university in Seoul. Participants took TOEIC tests before taking the classes and were divided into two different proficiency level groups: a high-level group and a low-level group. All participants studied English via both pre-recorded video lectures and video-conferencing (Zoom) for the whole semester. Questionnaires were carried out to explore students’ perspectives on both online formats in accordance with their proficiency levels. The findings of the closed-ended questionnaires revealed that significant differences were not found between the low- and high-level groups regardless of the online learning formats. Regarding students’ perspectives about these online English formats, a statistical difference was not found between the two groups. It is worth noting that students did not show any significantly different perspectives concerning online courses regardless of their proficiency levels. As for the open-ended questionnaires, both groups noted various benefits and drawbacks of the current online learning platforms. Also, they provided constructive suggestions for these online learning formats. The results of this study have pedagogical implications for carrying out successful online courses.

Critical Temperatures for Initiating and Arresting Delayed Hydride Cracking in a Zr-2.5Nb Pressure Tube

Kim, Young Suk,Im, Kyung Soo,Cheong, Yong Moo Trans Tech Publications, Ltd. 2005 Key Engineering Materials Vol.297 No.-

<P>The hydrogen concentration limit and critical temperatures for a delayed hydride cracking (DHC) in zirconium alloys have been reanalyzed using Kim’s DHC model that a driving force for DHC is not the stress gradient but the supersaturated hydrogen concentration or ∆C arising from a hysteresis of the terminal solid solubility on a heating and on a cooling. The DHC initiation occurs generally at the temperatures corresponding to the terminal solid solubility for precipititation (TSSP), demonstrating that the supercooling from the terminal solid solubility for dissolution (TSSD) is required to initiate the DHC. The DHC arrest temperatures correspond to the temperatures where the ∆C is reduced to zero. Therefore, we conclude that the ∆C is the driving force for the DHC and that the Kim’s DHC model is feasible.</P>

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.

PVA-ECC를 활용한 Half PC 복합체의 역학적 특성에 관한 실험적 연구

김재환,김영덕,김갑수,조봉석,장종호,김무한 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

ECC represents one particular class of HPFRCC, which are defined by an ultimate strength higher than their first cracking strength and the formation of multiple cracking during the inelastic deformation process. This study is to provide the fundamental data for the development of hybrid construction method such as the half PC(Precast concrete) reinforced by PVA-ECC, the mechanical properties of half PC according to the alteration of properties of PVA-ECC in terms of the type of fiber, Vr, S/M, placing height of PVA-ECC, are experimentally investigated. As the results. it is found that the half PCs of PVA-ECC have very higher mechanical performance in terms of yield load, strain capacity beyond yield point and maximum flexural load than that of mortar. Also, flexural crack in the half PCs of PVA-ECC are not localized at first crack and are growed to many micro crack, especially multiple cracking in specimen of P(12)-30-0.1ㆍ3 occurred.

유니섹스모드 수용도와 성격 특성과의 관계 연구

김영숙,박은영,이영선,허영미,홍은영 효성여자대학교 가정대학 학도호국단 1985 家政大論集 Vol.4 No.-

The purposes of this study were 1) to investigate the relationship between theacceptance oF unisex mode and rigidity character and 2) to find out any significantdifference in the acceptance of unisex mode according to grade, major and sex. The questionnaires were administered to 133 female and 174 male college students. The results; 1. The accptance of unisex mode was not related with rigidity character. 2. The acceptance of female unisex mode was higher than male unisex mode. 3. Females showed higher tendency in the acceptance of unisex mode and fashioninnovativeness than males. 4. No significant differences were found in the acceptance of unisex mode accordingto grade and major level.