Dynamic Young's Modulus and Internal Friction in Polycrystalline Copper

Kang, Chang-Seog,Chang, Si-Young,Hong, Sung-Kil 대한금속재료학회 2003 METALS AND MATERIALS International Vol.9 No.5

An attempt has been made to measure the temperature dependence of dynamic Young's modulus together with the related variation of internal friction in polycrystalline copper. A mechanical spectroscopy study was employed using a standard servo hydraulic fatigue testing machine equipped with a scanning laser extensometer. Dynamic Young's modulus and internal friction were measured over a temperature range of 298 to 873 K at very low frequencies of 0.1, 0.05, and 0.01 Hz. One internal friction peak was observed over the ranges 450 to 700 K, together with marked decreases in the dynamic Young's modulus in the same temperature range. From a quantitative analysis of the experimental data with the relaxation strength, relaxation time, and activation energy, it is concluded that the peak phenomenon is due to grain-boundary sliding relaxation.

흰쥐 간의 재생에 관한 세포화학적 연구

길영천,김완종,한상철 순천향대학교 기초과학연구소 1998 순천향자연과학연구 논문집 Vol.4 No.2

The present study was designed to evaluate the regeneration process, the localization of metallothionein(MT) and alkaline phosphatase(ALP), and the liver function during the liver regeneration of rat. The weight of control rat liver was about 4.3% of body weight. But after hepatectomy, the remaining liver weight was about 1.3% of body weight. The remaining liver seemed to begin regenerating at 24 hours after partial hepatectomy, and to complete at 7∼10days after hepatectomy. In control rat liver, metallothionein(MT) was scarcely found in the cell. But MT was found in both the cytoplasm and the nucleus of hepatocyte at 6 hours after hepatectomy, and MT reaction was found in the cytoplasm of liver at 24 hours after hepatectomy. From 5 days after hepatectomy, MT reaction became weak in the cytoplasm of hepatocytes. In control rat liver, the reaction products of alkaline phosphatase(ALP) were scarcely found in the nucleus. But in the experimental group, ALP was found at the membrane of hepatocyte contacted with the lumen. Activities of glutamate oxaloacetate transaminase(GOT) and glutamate pyruvate transaminase (GPT) of serum increased until 24 hours after hepatectomy, then returned to the normal level in about 2 days after hepatectomy. In conclusion, It is suggested that regenerating hepatocytes reveal characteristics of typical cell proliferation and carry out normal function.

높은 지향성을 갖는 Air Line 결합기 설계

길준범,이성원,최영호,박종임,안달,박준석 호서대학교 반도체제조장비국산화연구센터 2000 학술대회 자료집 Vol.2000 No.1

본 논문에서는, 일반적인 스트립 구조의 결합기가 갖는 문제 즉, 높은 온도에서 나쁜 특성을 보이는 문제점을 극복하고자 Air Line Type의 결합기를 구현하였다. 또한 이 결합기는 24dB이상의 지향성을 가지고 있다. 해석을 위해 짝수 모드와 홀수 모드 해석법을 사용하였고, EM-Simulation으로 확인한 특성과 실제 제작된 20dB, 30dB Cellular 대역(800∼900MHz) Air Line 결합기의 결고 특성은 좋은 일치를 보여주고 있다. 또한 최대 장점인 온도 특성은 온도 데이터를 통하여 온도에 강한 특성을 보임을 알 수 있다.

슬라이딩 섹터에 근거한 제어기 설계

배상현,손영수,한종길 조선대학교 전자정보통신연구소 2001 電子情報通信硏究所論文誌 Vol.4 No.2

A sliding sector is defined as a subset the state space, inside which some norm of state decreases with zero control input. The variable structure controller with sliding sector is designed to transfer the system state from the outside to the inside of the sliding sector in a finite time and enable the system state stay inside the sliding sector, and the resulted VS control system is quadratically stable. The simulation results are its effectiveness.

급박 하지 허혈증에 대한 비수술적 치료의 장기 추적 결과

최재영,손민수,이길연,이상목,고석환,홍성화,윤층,오수명,박호철 대한혈관외과학회 2003 Vascular Specialist International Vol.19 No.1

포도당과 이소프로테레놀에 의한 시상하부의 소마토스타틴 분비가 갑상선자극호르몬방출호르몬에 의한 갑상선자극호르몬에 미치는 효과

박철영,양인명,오승준,김덕윤,우정택,김성운,김진우,김영설,최영길 대한내분비학회 2000 Endocrinology and metabolism Vol.15 No.4·5

제한속도 규제와 그 영향에 대한 분석

이원영,성낙문,박길수 한국안전교육학회 2002 한국안전교육학회지 Vol.5 No.2

This study purposes to provide a rational direction to the policies associated with speed limits of Korea through literature reviews. As a result of analysis, it is generally accepted that the higher running speed and speed limit bring about the more traffic accident frequencies and the higher severity. Traffic safety experts strongly confirm that speed variances affect the occurrences of the traffic crashes. An inappropriate speed limit increases the speed variances and becomes a factor of the occurrences of traffic crashes. Accordingly, the speed limit should be determined in appropriate manner. This means that speed limit should be installed considering running speeds of vehicles and geometries of the road. There have not been reliable researches related to speeds and traffic crashes in Korea, even though the speeds have an very important role for the occurrence of traffic crashes. Therfore it is required that researches related to the traffic crash and traffic safety should be conducted actively in Korea.

개심술후 정신의학적 합병증

임기영,조범구,민성길,이홍식,유계준 大韓神經精神醫學會 1985 신경정신의학 Vol.24 No.1

Pre-and post operative psychiatric evaluations were done using semi-structured interview with Hamilton scales for anxiety and depression in 57 open heart surgery receipients to assess post-operative psychiatric complications. Conspicuous post-operative psychiatric complications were observed in 16 (23%) of 57 patients after open heart surgery. Postcardiotomy delirium occurred in seven patients; acute psychotic reaction with paranoid ideation in one; and neurotic reaction in eight. Factors that tended to influence postoperative psychiatric complications were older age, unempolyment, previous medical/psychiatric history, and high level of preoperative anxiety. By analysis of the preoperative psychiatric evaluation, patients could be largely divided in 3 groups; anxiety group, denial group, and adjusted group. Excessive anxiety and massive denial seemed to be signficant in the postoperative psychiatric compliactions. With these findings, the author's impression was that the consultation psychiatrist should give comprehensive psychiatric evaluation and psychiatric preparation in pre-and post-open heart surgery for the possible prevention of postopertive psychiatric complications.

한국판 세계보건기구 삶의 질 간편형 척도(WHOQOL-BREF)의 개발

민성길,이창일,김광일,서신영,김동기 大韓神經精神醫學會 2000 신경정신의학 Vol.39 No.3

연구목적 : 본 연구는 한국판 세계보건기구 삶의 질 간편형 척도(이하 한국판 WHOQOL-BREF)를 개발하고, 한국판 WHOQOL과 비교하여 그 타당도 및 신뢰도를 검증하고자 하는 것이다. 방 법 : WHO의 지침에 따라 개발된 한국판 세계보건기구 삶의 질 간편형 척도(WHOQOL-BREF)를 연세대의대부속 신촌 세브란스 병원에 내원한 일반 내과 환자 171명과 건강한 대조군 367명을 포함한 583명을 대상으로 평가하였다. 총 489명의 응답자가 최종적으로 연구대상이 되었다. 검사-재검사 신뢰도를 보기 위하여 3주 간격으로 113명에게 재검사를 시행하였다. 결 과 : 검사-재검사 신뢰도는 원척도인 WHOQOL과 WHOQOL-BREF두 개 척도 모두 모든 항목에서 유의하게(p<0.0001) 높았다. 원척도인 한국판 WHOQOL과 한국판 WHOQOL-BREF에서 영역(domain)별 점수의 차이는 매우 작았다(평균 0.49). 그리고 두가지 척도의 점수간에 유의한 상관관계가 있었다.(p<0.0001). 내적 일관성에 있어 Cronbach's α는 0.898(0.583∼0.777)이었으며 각 영역(domain)에서도 높은 일관성을 보였다. 변별타당동에서는 성별, 나이, 교육수준, 결혼여부, 질병의 유무에 따라 차이가 있었으며 특히 교육수준과 질병의 유무에 따른 차이가 유의하게 관찰되었다. Confirmatory factor analysis 결과 네 개의 영역구조가 적절하다는 것이 판명되었다.(Bentler의 comparative fit index : 0.859). 전반적인 삶의 질의 평가에 있어서 신체적 건강 영역이 가장 높게 공헌하였고 심리적 영역과 환경 영역이 그 다음으로 공헌하였다. 결 론 : 한국판 WHOQOL-BREF가 삶의 질을 측정하는 도구로써 원척도인 한국판 WHOQOL만큼 신뢰롭고 타당한 검사인 것으로 나타났다. Objective : This study proposed to develop the Korean version of the WHO Quality of Life Scale Abbreviated Version(WHOQOL-BREF) and to test the validity and reliability of the Korean version of WHOQOL-BREF compared with the Korean version of WHOQOL. Method : The Korean version of the WHOQOL-BREF, which was developed according to WHO guidelines, was piloted on 538 respondents, including 171 medical patients from outpatient clinics at Severance hospital and 367 healthy subjects. A total of 489 respondents completed the study. To assess the test-retest reliability, 113 subjects repeated the rating within a 3-week interval. Results : Correlations for test-retest reliability in all item scores of Korean versions of the WHOQOL and WHOQOL-BREF were highly significant(p<0.0001). Differences between domain scores of the Korean version of the WHOQOL-BREF and those of the Korean version of WHOQOL were very small(mean differences=0.49). Domain scores produced by the Korean version of WHOQOL-BREF correlated significantly(p<0.0001) with those of the WHOQOL. Cronbach alpha values were 0.898 and values for each domain were also high(0.583-0.777), which demonstrated good internal consistency. As for determining discriminant validity, scores were compared between gender, age groups, education levels, marital status, and health status. Differences in education levels and health status were statistically significant. Confirmatory factor analysis showed that four domain structures were appropriate(Bentler's comparative fit index : 0.859). For overall quality of life, the contribution of physical health domain was highest, followed by psychological and environmental domains. Conclusion : This study shows that the Korean version of the WHOQOL-BREF is a reliable and available test for assessing quality of life.

다발성 원발성 악성 종양의 임상적 고찰

오상훈,김경기,최영길,홍관희,김상효 인제대학교 1995 仁濟醫學 Vol.16 No.3

다발성 원발성 악성 종양은 최근 평균 수명의 증가, 악성 종양의 진단과 치료법 및 종양 역학 분야의 발달로 발견 빈도가 증가하고 있을 뿐 아니라 분자 생물학의 발달로 그 발생 기전에 관한 연구와 이차암의 약물 예방 요법에 관한 연구가 활발하게 이루어짐으로 해서 더욱 관심이 모아지고 있다. 1980년부터 1993년까지 인제대학교 의과대학 부속 부산백병원 외과학교실에서 경험한 다발성 원발성 악성 종양 47례를 분석하였다. 다발성 원발성 악성 종양의 발생빈도는 0.84%이고 동시성 암이 29례 위암과 폐암, 위암과 자궁 경부암이 높은 빈도로 관찰 되었다. 악성 종양의 가족력이 있거나 제1암의 수술 후에 항암 약물 요법이나 방사선 조사 등의 부가적인 치료를 시행하는 경우 추적 기간 중에 항상 다발성 원발성 악성종양의 발생 가능성을 고려하여 발암 물질에 노출을 피하도록 하며 철저한 추적조사를 통한 제2 암의 조기 진단 및 치료로 암 환자의 생존기간을 더 연장할 수 있다고 생각된다. The incidence of multiple primary malignant neoplasm(MPMN) in an individual is in gradual and steady increase with the time as reported in many literature. This increase has been attributed to the fact that the average lifespan of cancer patients was remarkably prolonged with a striking development of cancer surgery, postoperative adjuvant therapy, and diagnostic and interventional radiology. Authors reviewed forty seven patients with multiple primary malignant neoplasm among 5,534 cancer patients registered in Pusan Paik Hospital from 1980 to 1993. The overall incidence of multiple primary malignant neoplasm was 0.84%, synchronous neoplasm was 29 cases and metachronous was 18 cases. The sex ratio of male to female was 1.2 : 1 The mean age of the patients with synchronous neoplasm at diagnosis was 57.4 years old and metachronous neoplasm at first cancer was 48.5 years old. In metachronous neoplasm, the mean time interval between 1st and 2nd neoplasm was 67 months. There was one familial MPMN affected by stomach and colon cancer. The most frequent combination site was stomach and colorectal cancer. Blood group A was most common in synchronous and metachronous neoplasm (55%). Therefore, in order to get longer survival period in cancer patients, it is important to make early detection of second cancer in same patient with careful follow-up and examination, and to avoid the exposure of the carcinogenic material in the high-risk patients, based on awareness of the possibility of second cancer.