LiCoO₂의 합성 공정변수에 따른 리튬이차전지 정극의 전기화학적 특성 연구

이철태,오치훈,엄의흠,송연호 조선대학교 생산기술연구소 2003 生産技術硏究 Vol.25 No.2

리튬이차전지용 정극활물질 LiCoO₂를 소성법 을 이용하여 합성공정변수를 달리하여 합성하고 합성공정변수가 이들의 물리화학적인 재료특성 및 전기화학적인 특성에 미치는 영향을 조사하였다. 출발 물질로 LiOH · H₂O와 Co₃O₄를 사용하였으며, 750℃, 6시간 이상의 조건에서 결정의 LiCoO₂가 합성되기 시작하였으며, 반응온도가 높아지고 반응시간이 길어질수록 LiCoO₂의 결정성이 증가하였다. 여러 합성 조건 중 가장 우수한 전기화학적 특성을 보이는 조건은 반응옹도 750℃ 반응시간 24시간이었다. 이 조건에서 합성한 LiCoO₂로 Li/1M LiCIO₄ in PC + DME/LiCoO₂의 cell을 구성한 후 0.25mAh/㎠며의 전류밀도로 충 · 방전 하였을 경우 초기 방전 용량은 130mAh/g이였으며, 10cycle 후 방전 용량은 130mA h/g에서 109mAh/g으로 16%의 용량감소가 일어났다. LiCoO₂, the active material of positive electrode in lithium secondary battery, was synthesized by calcination with LiOH · H₂O and C0₃O₄. And relationships between synthesis condition and physical and electrochemical characteristics of LiCoO2 were investigated. Synthesis condition of 750℃, 6hr, LiCoO₄ crystal began to be formed, and the crystallinity of LiCoO₂ increased with reaction temperature and reaction time. LiCoO₂ synthesized by calcination at 750℃ during 24hr showed best electrochemical characteristics. The initial discharge capacity of LiCoO₂ synthesized under this condition was 130mAh/g, and after 10 cycles, the discharge capacity decreased to 109mAh/g.

발자크의 초기소설에 나타난 시대인식 : <마법의 가죽> 을 중심으로

이철의 상명대학교 어문학연구소 1996 語文學硏究 Vol.4 No.-

역사, 현실, 소설 : 발자크의 소설관에 관한 한 연구 Une etude sur la conception balzacienne du roman

이철의 상명대학교 어문학연구소 1995 語文學硏究 Vol.3 No.-

운동 중 지방 대사에 대한 고찰

이근일,백병주,김의영,김도준,조용철,정훈,조재혁 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

Glucose-fatty acid cycle is very important because it explains that fatty acid influences glucose level. Glucose-fatty acid cycle is the key factor to understand how endurance training which aids fat oxidation and carbohydrate stored in skeletal muscle influence mitochondria level. However, it is not certain whether glucose-fatty acid cycle influences exercising skeletal muscle of human being. As an energy resource, training increases use of fatty acid, endurance ability, and oxidation of triglyceride. During high level training, catecholamine secretions and restraint of fatty acid use caused by insulin increases dramatically, this results in reduction of free fat acids and reunification of free fat acids into triglyceride. Training restrains insulin activity and reduces plasma acid density, however, elite athletes have high triglyceride-fatty acid cycle. Although enzyme's activities and mitochondira's density increase after training, it's not certain that enzyme's activities is major factor in restraint of fatty acid oxidation in exercising muscle cells. Stores of fat leads to increases of fat oxidation, performance and reduces use of carbohydrate, however, there is no absolute evidence to support these results.

섬유종류 및 잔골재용적비에 따른 HPFRCC의 공학적 특성에 관한 실험적 연구

이의배,이동혁,나철성,조봉석,김재환,김무한 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1(구조계)

In general, concrete showed brittle fracture but HPFRCC(High Performance fiber reinforced cementitious composite) showed ultra high ductile behavior in the hardened state, because of the fiber bridging properties. So a variety of experiments have being performed to access the performance of HPFRCC recently. In this study, to develope HPFRCC with high ductility and strain capacity, effects of fiber types and sand volume fraction were investigated. And results of this study were as follows; · HPFRCC reinforced with PVA or hybrid fiber were superior to PP or singleness. · Effect of sand volume fraction on HPFRCC reinforced with PP was insignificant.

울산지역 초, 중, 고등학생들의 자기 체형에 대한 인식 및 불만족도에 대한 조사

홍찬의,홍성완,정철주,이동진,최광해 영남대학교 의과대학 2008 Yeungnam University Journal of Medicine Vol.25 No.2

Background : In this study, we examined body image perception and dissatisfaction with weight and height in children and adolescents, according to age and body mass index. Additionally, we compared our findings with those of previous studies concerning eating disorders. Materials and Methods : In July and August 2008, 1,501 students were sampled from elementary, middle, and high schools in Ulsan and assessed using self-completion questionnaires. We used the Korean version of the Eating Attitude Test-26 (EAT-26) to screen for eating risk groups Participants were stratified by grade, gender, and body mass index. Results : 1) Dissatisfaction with height, weight, and body image was greater in the older group. 2) Dissatisfaction with weight and body image was greater in the heavier group. 3) EAT-26 scores and the number of individuals at high risk for eating disorders were higher in the female group than in the male group. Conclusion : The EAT-26 score in this study was similar to those found in Previous Westem studies. 2) There were a number of high-risk individuals in the female group, with a tendency toward earlier Presentation. Continuous health management and prevention programs are required.

투기종목 선수들의 무산소성 역치의 특성

조현철,송순천,김춘경,김의영,안용규,이규석,김학렬 龍仁大學校 體育科學硏究所 1991 體育科學硏究論叢 Vol.1 No.1

The purpose of the present study is to determine the levels of maximal oxygen uptake and anaerobic threshold of boxing players(n=23), ken-do players(n=18), Judo players(n=12), T.D.K players(n=18). Treadmill test was used to measure maximal state and anaerobic threshold of metabolic variables. Treadmill exercises protocol was 2-min incremental test from an initial work load of 0MPH(grade : 0%) to all-out by step of 1.0MPH(grade : 2%). The results of measurement was as follows : 1. Absolute(1/min) and relative(ml/kg/min) maximal oxygen uptake was highest(5.08l/min, 65.01 ml/kg/min) in Judo layers, followed in order by the T.D.K players (4.37l/min, 64.74 ml/kg/min), Boxing players(4.18) l/min, 63.19 ml/kg/min) and ken-do players(3.81l/min, 58.65 ml/kg/min). It is not significant difference in the relative maximal oxygen uptake, but is significant difference between group in the absolute maximal oxygen uptake(p<0.001) 2. AT-VO₂(l/min) and AT-VO₂(ml/kg/min) in the anaerobic threshold was highest (3.71 l/min, 47.28 ml/kg/min) in Judo players, followed in order by the T.K.D players(3.29 l/min, 48.75 ml/kg/min), boxing players(2.90 l/min, 43.91 ml/kg/min) and ken-do players(2.82 l/min, 43.52 ml/kg/min). It is not significant difference in the AT-V02(ml/kg/min), but is significant difference between group in the AT-V02(l/min). (p<0.001) 3. %HRmax and %V 02max in the anaerobic threshold was not significant difference between group.

씨큐리트 종사자의 직무스트레스에 관한 연구

김의영,임승혁,이재학,강민철 龍仁大學校 武道硏究所 2004 武道硏究所誌 Vol.14 No.2

The purpose of this study was to determine the relationship of demographic characteristics to job stress among security guards. The subjects in this study were 474 people selected by random cluster sampling from a population that consisted of private bodyguards and security guards from Seoul, Gyeonggi province and Daejeon. They gave a faithful response when a survey was conducted, and incomplete answer sheets from the others of the population were excluded. For data analysis, SPSS/PC Windows V11.0 program was utilized, and frequency analysis, t-test, one-way ANOVA and Scheffe posttest were employed. The findings of this study were as follows: First, the gender of the security guards investigated made a significant difference to their job satisfaction(p<.05). Job characteristics, compensation and organizational characteristics put higher strain on the men than on the women, and the latter group was more stressed out about their roles and interpersonal relations. Second, their age, education, years of services and monthly income made a significant difference to their job stress subvariables related to job characteristics, roles, human relations, compensation and organizational characteristics(p<01). Third, their job stress was significantly different according to their position and status(p<01). Specifically, those who had no position were under heavier pressure due to job characteristics, roles, interpersonal relations, compensation and organizational characteristics.

측두골 전산화단층촬영의 3차원 재구성의 의의 : Normal and Pathologic Temporal Bones

서정출,고의경,전경명,김재혁,이동건 釜算慶南耳鼻咽喉科學會 1994 임상이비인후과 Vol.5 No.1

집단에 따른 노인들의 자가건강관리행태, 일상생활수행능력, 신체적 자기효능감에 관한 연구

김세종,이의철,염원상,서혜림,백영호 釜山大學校 附設 體育科學硏究所 1998 體育科學硏究所 論文集 Vol.14 No.-

This study was carried out to identify the status of self-care, activity of daily living and physical self-efficacy among aged people in Pusan and thus to provide basic data for maintaining health, making affirmative-self among elders. The subjects of this study were 761 elders 65years and over in Pusan. The means of measurement used were the status self-care scale, activity of daily living scale and physical self-efficacy scale. The data was used by One-way Anova, Duncan's Multiple Range and Pearson's Correlation Coefficient as statistical method. The level of significance of all hypotheses tested was p<.05 and the results were as follows; 1) Aged people who participated in elderly academy classes was higher than other groups in the status of self-care statistically significant. 2) Aged people who participated in elderly academy classes and elderly houses ·respect for age association and group were higher than other groups in activity of daily living statistically significant. 3) Aged people who participated in elderly academy classes, elderly house ·respect for age association and just stay at home group were higher than other group in physical self-efficacy statistically significant. 4) Aged people's status of self-care, activity of daily living and physical self-efficacy was statistically significant correlation with each other.