Experimental and Numerical Method for Thermal Conductivity of Offshore Sediment and Proposed OHTC Formula for Offshore Pipelines Taking Multi-layered Sediment

해저배관은 오일, 가스 그리고 불순물의 혼합물을 유정에서 운송할 수 있 도록 고안되었으며, 100℃전후의 높은 온도의 유체를 수송한다. 하지만 높은 온도의 수송유류와 반대로 해저배관을 둘러싸고 있는 주변 환경의 온도는 5℃정도의 낮은 온도를 유지하고 있으며 이로 인해 해저배관은 열손실이 발 생한다. 따라서 해저배관의 열손실을 최소화 하는 것 즉, 수송유류가 왁스 (Wax)나 고상염(Hydrate) 같은 침전물이 생성되는 온도인 40℃ 이하로 떨어 지는 것을 방지해 유동안정성을 확보하는 것은 해저배관 설계에 있어 가장 중요한 부분이다. 그러므로 해저배관 주변 환경 즉 해수, 해저지반의 영향에 의한 해저배관의 열손실의 정도를 나타내는 총괄열전달계수를 계산하여 설 계에 반영하는 것은 중요하다. 본 논문에서는 실내모형실험 및 CFD해석의 검토를 통해 해저지반의 열전도율을 여러 가지 샘플을 통해 산정하였으며, 산정된 열전도율을 토대로 다층지반을 구성하여 다층지반의 다양한 열전도 율을 고려한 해저배관의 총괄열전달계수(OHTC)식을 제안하였다.|Subsea pipelines are designed to transport mixtures of oil, gas and their associated impurities from the wellhead that can be in excess of approximately as high as 100℃ temperature, while the external temperature maybe in the range of 5℃. Heat can be lost from the subsea pipeline which contains high temperature fluid to the surrounding environment. It is important that the pipeline must be designed to ensure that the heat loss is small enough to maintain flow assurance, unwanted deposition of hydrate and wax, which occurs at a critical temperature of about 40℃. Therefore it is essential to know heat loss of subsea pipeline in various circumstance. This paper presents thermal conductivity of offshore sediments using laboratory model test and numerical analysis for various soil samples. After calculate thermal conductivities, this paper propose a OHTC(Overall heat transfer coefficient) formula considering multi-layed soil using calculated thermal conductivity of soil samples for more precise OHTC estimation.List of Tables ··············································································································· ⅳ List of Figures ············································································································· ⅴ Abstract ························································································································· ⅶ 초록 ································································································································ ⅸ 제 1 장 서 론 ·············································································································· 1 1.1 연구 배경 ······································································································ 1 1.2 연구 동향 ······································································································ 2 1.2.1 해저지반 열전도율 산정 ································································· 2 1.2.2 다층지반을 고려한 총괄열전달계수식 제안 ······························· 3 제 2 장 해저지반 열전도율 산정 실내모형실험 ·················································· 5 2.1 실내모형실험 방법 ······················································································ 5 2.1.1 실내모형실험 장치 ··········································································· 5 2.1.2 실내모형실험 측정 장비 ································································· 7 2.1.3 실내모형실험 방법 ··········································································· 8 2.1.4 실내모형실험 시료 ········································································· 10 2.2 실내모형실험 결과 ···················································································· 12 2.2.1 혼합시료 열전도율 결과 ······························································· 12 2.2.2 보링시료 열전도율 결과 ······························································· 18 제 3 장 해저지반 열전도율 산정 유한요소해석 수행결과 및 분석 ·············· 20 3.1 유한요소해석 타당성 검토 ······································································ 20 3.2 유한요소해석 방법 ···················································································· 22 3.2.1 모델링 및 격자생성 ······································································· 23 3.2.2 유한요소해석 지배방정식 ····························································· 24 3.2.3 유한요소해석 초기조건 및 경계조건 ········································· 25 3.2.4 유한요소해석 항목 및 재료 물성치 ··········································· 25 3.3 실내모형실험 및 유한요소해석 결과비교 및 분석 ···························· 26 3.3.1 유한요소해석 및 실내모형실험 결과 ········································· 26 3.3.2 유한요소해석 및 실내모형실험 결과 비교 ······························· 27 제 4 장 다층지반의 열전도율을 고려한 총괄열전달계수식 제안 ·················· 30 4.1 총괄열전달계수 이론식 검토 ·································································· 30 4.1.1 총괄열전달계수 개념 ····································································· 30 4.1.2 매립된 해저배관의 총괄열전달계수 이론식 ····························· 30 4.2 다층지반 열전도율 적용 이론 및 식 제안 ·········································· 36 4.2.1 Fourier의 열전도법칙 ····································································· 36 4.2.2 해저지반 등가 열전도율 산정 ····················································· 38 4.2.3 다층지반을 고려한 총괄열전달계수 계산식 ····························· 39 제 5 장 유한요소해석을 통한 제안 식 검증 ······················································ 42 5.1 유한요소해석 방법 ······················································································42 5.1.1 유한요소해석 방법 ········································································· 42 5.1.2 유한요소해석 지배방정식 ····························································· 44 5.1.3 유한요소해석 초기조건 및 경계조건 ········································· 46 5.1.4 수치해석 결과를 이용한 총괄열전달계수 계산 이론 ··········· 48 5.2 유한요소해석 케이스 ·············································································· 49 5.2.1 해석케이스 1 : High Biot number ·············································· 50 5.2.2 해석케이스 2 : Intermediate Biot number ································ 51 5.2.3 해석케이스 3 : Law Biot number ··············································· 52 제 6 장 유한요소해석 수행결과 및 분석 ···························································· 53 6.1 유한요소해석 타당성 검토 ······································································ 53 6.2 유한요소해석 결과 및 제안 식 계산결과 비교분석 ·························· 55 6.2.1 해석케이스 1 : High Biot Number ·············································· 55 6.2.2 해석케이스 2 : Intermediate Biot Number ······························· 58 6.2.3 해석케이스 3 : Law Biot Number ·············································· 61 제 7 장 결 론 ············································································································ 64 Nomenclature ············································································································· 66 참고문헌 ······················································································································ 68Maste

Prognostic Significance of Multifocal Tumor in Radical Prostatectomy

Purpose: We investigate the impact of tumor multifocality on the biochemical recurrence rate after radical prostatectomy. Materials and Methods: Data was collected from 525 patients who underwent radical prostatectomy for clinically localized prostate cancer from 2003 to 2007. We evaluated the potential associations of multifocality with various clinical and pathologic factors. The ability to predict extra-capsular extension (ECE) was tested by logistic regression models, whereas biochemical recurrence (BCR) was assessed via Kaplan-Meier analyses and Cox-hazard regression models. The BCR was defined as a level of serum prostate-specific antigen (PSA) of 0.2ng/ml or greater on consecutive evaluations. Results: Multifocality was observed to be significantly associated with the presence of a high grade Gleason pattern (p=0.014), the pT stage (p＜ 0.001), ECE (p=0.005) and a positive surgical margin (PSM) (p=0.019). Moreover, it was the independent predictor of ECE on multivariate logistic regression analyses (p=0.039). However, although multifocality had a significant influence on biochemical recurrence on the Kaplan-Meier analyses (log rank test, p=0.019), only the PSA level and the Gleason score were significant predictors of BCR on the multivariated Cox-hazard analyses. Conclusions: Although multifocality was associated with adverse pathologic features, it had no significant effect on biochemical recurrence on the multivariated cox-hazard analyses

(A) Study on the Knowledge and Attitude toward Medical Market Opening: Opinions from Hospital Managers in 4 University Hospitals

보건관리학과/석사[한글] 대학병원 관리자들의 의료서비스 시장개방에 대한 인식을 조사하기 위하여 서울소재,500병상 이상의 4개 대학병원의 관리자 520명을 대상으로 하여 1994년 3월 28일부터 1994년 4월 8일까지 구조화된 자기조사표를 이용, 자기기입식 방법으로 연구자료를 수집하였으며, 인구에서 분석된 표본수는 319건 이였다. 주요결과는 다음과 같다. 첫째, 의료시장 개방의 긍정적 인식정도는 시설 측면의 경우 국립병원이 사립병원에 비해 통계학적으로 유의하게 높았으며, 부정적 인식정도는 경영측면의 경우 간호부서에서 남자보다는 여자가, 약무직종에서 통계학적으로 유의하게 높았으며, 의료서비스 측면의 경우는 부정적 인식정도가 약무직종이 통계학적으로 유의하게 높았다 둘째, 응답자의 지식정도에 따른 의료시장개방의 긍정적 인식정도는 경영 측면의 경우 해외연수 교육을 받은 경험이 있다고 응답한 군이 그렇지 않은 군에 비해 통계학적으로 유의하게 높았으며, 의료서비스 측면과 시설측면의 경우 개방에 관한 자료를 반드시 본다고 응답한 군과 개방화 자료가 근무에 도움을 준다고 응답한 군이 긍정적 인식정도가 통계학적으로 유의하게 높았다. 세째, 개방의 태도에 따른 의료서비스 개방의 긍정적 인식정도는 경영측면의 경우 해외연수교육이 매우 바람직 하다고 응답한 군이 통계학적으로 유의하게 높았으며, 개방의부정직 인식정도는 경영측면의 경우 해외연수교육이 전혀 바람직하지 못하다고 응답한 군이 부정적 인식정도가 통계학적으로 유의하게 높았다. 냇째, 전체 의료정칙에 관한 개선정도는 사립병원과 과장급 이상에서, 의료수가 수준의 현실화에 대한 개선 인식정도는 사립병원과 행정부서에서 통계학적으로 유의하게 높았으며, 의료기관을 지원하기 위한 제도마련은 사립병원에서, 과장급 이상의 직위에서 통게학적으로 유의하게 높았다. 다섯째, 의료서비스 시장개방에 대처하기 위해 시설과 장비 및 자본에 대한 대응이 있어야 한다고 근무년수가 20년 이상에서, 경영전략으로 의료의 질이나 서비스 수준은 향상시켜야 한다고 과장급이상의 직위에서 통계학적으로 유의하게 많았다 이 연구에서 제시된 결과들에 비추어 의료서비스 시장개방에 대처하기 위해 경쟁력강화를 위한 병원 스스로의 자구 노력이 시급하며, 의료보험 수가제도의 혁신이 시급히 강구되어야 하며, 모든 병원이 의료의 질 과 서비스 향상을 통해 국민의 지지를 확보하여야 한다. 아울러 병원이 사회조직의 일원임을 상기하여, 사회봉사에 참여하고 공익에 기여하는 자세를 갖추어야 하겠다. 병원의 특성이나 응답자들이 인식한 특성을 감안한 병원정책수립이 필요하며 앞으로 의료개방이라는 과제를 의료인과 관리자는 예외없는 관세화를 표방하는 무한경쟁 시대의 흐름을 인식하고, 각자가 속한 의견집약체를 중심으로 함께 모여 문제의 핵심을 정확히 진단하고 대응하여 평소에 개방에 대한 교육, 훈련, 인구가 필요하다, 이 연구는 병원관리자에 적합한 관리방안을 모색하는데 참고자료로 제시되었으면 한다. 또한 이 연구가 우리나라 전체병원을 대표하지 못하며 일부 응답자의 누락으로 전체병원관리자를 포함시키지 못하였던점 등의 제한점은 있으므로 이 연구의 제한점을 보충한 추가 연구가 진행되어야 할 것이다. [영문] In order to study major factors related to hospital managers a kind of questionaire which each relative subject should complete a constructed form of a check list by himself or herself was distributed to 520 hospital managers who had come to one of 4 located in Seoul city, university hospitals and was working from March. 28 to April. 8, 1995. However, 319 samples were respondent for analysis. And major results are as follow s' First of all, if the domestic market is opened those working in public hospitals agree more so than those working in private hospitals that the facilities sector of the hospital industry would be improved. But the negative aspect, as viewed by nurses, female in particular, and pharmacists, is that hospital income as well as qualified workers will be lost to foreign medical servicer. Pharmacists more so than other also believe that the medical service sector as a whole will suffer as a result of opening up the domestic market. Second, those who went abroad for medical seminars welcomed the idea of opening the medical service market more so than those who didn`t. Those who read materials concerning medical service and facilities also were more open to the idea of opening the medical service market. Third, those who went abroad for seminars also had a more positive attitude toward the opening of the medical service market. Forth, upper level management in public hospitals feel there is a need for change in insurance policies. The administration department in private hospitals feel the cost of medical feels should be raised and for the benefit of supporting medical centers a certain system must be developed. Fifth, for the benefit of managing the possible opening of the medical service sector, facilities, equipment, capital, medical care quality, and grade of service must be improved said those in upper level management as well as workers with 20 years or more experience. According to the results for the benefit of opening the medical service sector a medical policy must be established. Also, it would be beneficial if management from their respective hospitals can find a suitable method for administrative work. Because many doctors for various seasons decided not to participate in the questionaire and those in other areas other than Seoul were excluded the research may not accurately represent ????entiment of all doctors. So it would be helpful to do further research in this issue.restrictio

리더십 유효성과 리더십 및 팔로어십 스타일간 관련성에 대한 탐색적 연구

1999-12조직이란 두 사람 이상이 모여 공동목표를 달성하고자 하는 유기제이다. 그러한 조직의 목표를 효과적으로 달성하기 위해서는 조직을 구성하고 있는 개인 및 집단들의 협력이 매우 중요하며 이러한 개인 및 집단들의 협력은 그들과 직접적으로 상호작용하고 있는 리더의 역할이 없이는 실현될 수 없다. 다시 말해서 리더쉽은 개인행동과 집단행동의 형성은 물론 이들 행동을 조직의 설과로 연결시키는 직무행동개발에 가장 중요한 요인으로 인식되어 왔다. 그리하여 리더십은 조직관리에 있어서 가장 중요한 주제들의 한 분야로서 이론적 관심뿐만 아니라 조직에서의 실무적 관심의 대상이 되어 왔다. 지금까지의 대부분 리더십연구들은 리더십을 발휘하는 사람 즉 리더에게만 초점을 맞춰 리더십과 관련된 개념들을 개발하고 연구하는데 관심을 집중시켜왔다. 반면 팔로십은 리더십과정의 중요한 부분일 뿐만 아니라 조직운명에 중요한 역할을 하고 있음에도 불구하고 팔로어십 또는 팔로어의 역할에 대해서는 거의 연구가 이루어지지 않았다. 리더십연구들에서는 팔로어를 리더십 발휘 대상으로만 인식하여 왔기 때문에 팔로어십은 그 만큼 소홀히 다루어질 수 밖에 없었다

Histologic type, staging, and distribution of germ cell tumors in Korean adults.

OBJECTIVES: To investigate the presentation of germ cell tumors (GCT) in terms of histology and stage, to better clarify the epidemiology of this disease in eastern Asia. METHODS: Six hundred ninety-eight patients diagnosed with GCT between 1995 and 2004 were analyzed. Clinical parameters at the time of initial diagnosis were classified in terms of the American Joint Committee on Cancer (AJCC) tumor, nodes, metastasis staging (TNMS) system, the International Germ Cell Cancer Collaborative Classification (IGCCC), for high-risk stage I nonseminomatous GCT (NSGCT) of testis. RESULTS: The anatomic distributions for the primary sites of the observed tumors were as follows: testis 471 cases (67%); central nervous system (CNS) 137 cases (20%); mediastinum 78 cases (11%), and retroperitoneum 12 cases (2%); 239 (51%) of 471 tumors with testicular primary were seminoma. High risk vs. non-high risk stage I NSGCT cases were 62 vs. 58. of NSGCT of testis, 129 (58%), 73 (33%), and 21 (9%) of tumors presented with good, intermediate, and poor prognosis, respectively, based on IGCCC, whereas 231 (99%) patients were classified with a good prognosis and 3 (1%) with an intermediate prognosis amongst seminomas of testis; 193 (82%) cases presented as stage I testicular seminoma whereas 120 (54%) cases presented as stage I NSGCT. CONCLUSIONS: Extragonadal primary GCTs are very common in Korean. Incidence of high risk NSGCT of testis with stage I disease was lower than in the Western report. NSGCT presents itself as a more aggressive form whereas seminoma is a very indolent tumor when compared with cases in Western countries.ope

(The) prognostic factors in invasive and metastatic transitional cell carcinoma of the bladder

의학과/석사[한글] 방광의 침윤성 및 전이성 이행상피세포암 환자에서 처음 진다했을 때 존재하는 가능한 예후인자, 즉, 환지자의 나이나 성별같은 환자의 신체적 요인과 종괴의 형태, 위치, 크기, 조직학적 분화도, 병기, 임의생검에서의 비정상 조직소견 유무 및 요세포검사결과 등의 종물자체의 요인 및 진단후 치료방법, 근치적 방광적출 술전의 방사선치료에 의한 병리조직학적 감병기(downstaging)의 여부, 진행양상 등의 치료에 따른 요인들이 생존율에 어떠한 영향을 주는지를 검토하기 위학여 BMDP통계프로그램 package를 이요, 비교 분석하였다. BMDP1L을 이요해서 의의있는 예후추정인자를 알아보고 각 병기에 따른 생존율을 추정하였으며 Breslow와 Mantle-Cox 방법으로 검정하였다, 또한 BMDP2L을 이용한 희귀(regression)결과 나타난 가장 유의한 예후인자, 즉 임상 T병기를 중심으로 SPSS 통계프로그램 package를 사용, 원자료를 분류정리한 후 다른 예후인자와의 상호유의성을 Chi-square test로 검정하였다. 조사대상은 1977년 12월부터 1988년 3월까지 세브란스 병원 비뇨기과에 입원하여 초기 또는 추적 과정에서 침윤성 및 전이성 이행상피세포암으로 진단된 환자중 3개월 이상 관찰한 s138명의 환자이며, 상기의 방법으로 예후인자를 분석하여 다음과 같은 결과를 얻었다. 1. 임상 및 병리조직 T병기는 단독으로 예후에 영향을 주었다.(각각 p=0.004 및 <0.0001). 2. 종양의 수와 임상병기, 종양의 조직학적 분화도와 임상병기 및 치료방법과 임상병기는 각각 유의한 상관관계를 나타내었다(각각 P=0.002, 0.005 및 0.018). 3. 성별, 종양의 형태, 위치, 크기, N 및 M병기, 임의생검에서의 비정상 조직소견, 최초 요세포검사, 진행양상은 생존율에 단독으로 영향을 미치지 못하며, 각각은 임상병기와의 유의성도 없었다. 4. 임상병기 T2, T3 및 T4의 5년 생존율은 82.5%. 57.5% 및 32.5%로 다른 보고의 13-87%, 2-73% 및 9-20%와 비슷하지만 비교적 높은 결과를 보였다. 5. 병리조직병기 T2, T3a 및 T3b의 3년과 5년 생존율은 T2에서는 모두 82.5%, T3a에서는 각각 75%. 65%,T3b에서는 각각 32.5%, 0%로 다른 보고에 비해서 T2에서 높은 생존율을 보였다. 6. 임상병기의 오류는 31.80%(21/66)로 비교적 낮았다. 7. 비유두형 종양보다 유두형 종양으로 발현한 예가 밭았다. 8. 대부분의 예(72.73%, 48/66)애서 시행했던 방광 전적출술건 방사선 요법의 효과는 유의하지 않았다(P=0.7158). 이상의 결과로 보아, 예후에 단독으로 영향을 미치는 중요한 인자는 정확한 임상및 병리조직 T병기이며, 종양의 수와 조직학적 분화도는 임상T병기에 커다란 영향을 주었다. [영문] In order to evaluate the influential effect of the possible prognostic factors on survival which include the physical factors such as patient age, sex, the tumor factors such as mass shape, number, location, size, grade, stage, abnormal histopathology on random biopsy, urine cytology, the factors according to treatment such as treatment model, effect of downstaging of the preoperative radiotherapy, progression, etc., present at the initial diagnosis of either invasive or metastatic transitional cell carcinoma of the bladder, we reviewed the medical records of the selected 138 patient who were admitted to the Dept. of Urology, Severance hospital during the period from December 1977 to March 1988 and diagnosed either at the initial examination or in the course of follow up period, arts at the same time were followed for over 3 months. The date were analysed using the BMDP statistical program package. Therefore, they were analysed survival function of each prognostic factors using BMDPIL which were verified by Breslow and Mantle-Cox method. The raw data was classified, arranged using SPSS statistical program package according to the most important prognostic factor derived from BMDP2L regression of data and verified using Chi-square test. The results are as follow. 1. The clinical and histopathologic T swage were influential effect on survival independently(p=0.004 and <0.0001, respectively). 2. The number of the tumormass, histologic grade, and therapeutic methods were related to clinical stage respectively(p=0.002, 0.005 and 0.018, respectively) 3. Sex, tumor shaped location, size, N, M stage, abnormal histopathology on random biopsy, initial urine cytology and type of progression had neither a significant impact on survival independently, nor significant with the clinical T stage statistically. 4. The 5 year survival rate according to the clinical stage(T2; 82.5%, T3; 57.5%1, T4; 32.5%) is relativeily higher than other reports(T2; 13-87%,T3; 2-73%, T4; 9-20%). 5. The 3 & 5 year survival rate according to the pathologic stage is T2; 82.5%, T3a; 75%, 65%, and T3b: 32.5%, 0%, respectively. In this result, stage T2 was higher than that in other reports(60.75%). 6. The clinical staging error was 31.80%(21/66) which was relatively lower than that in other reports. 7. The papillary type of carcinoma was predominent comparing with non-papillary one. 8. The effect of preoperative radiotherapy performed in most of the patients before the total or radical cystectomy(72.73%, 48/66) was not significant statistically. The above results indicate that the clinical and pathologic T stapes were the independent prognostic factors. The number of the tumor mass and the histologic grade had a significant impact on the clinical stage.restrictio

사람 골수 줄기세포 유도 콜라겐 조직 재생에 미치는 2형 섬유아세포 성장인자의 역할

Dept. of Dental Science/박사Role of FGF-2 on Human Bone Marrow Stem Cells-induced Collagen Tissue RegenerationObjectives: Role of Bone Marrow Stem Cells (BMSCs) on collagen tissue regeneration, which is essential for wound healing process, might be modified by various biologic stimuli. The aim of this study was to assess the effects of fibroblast growth factor-2 (FGF-2) on collagen tissue regeneration by human BMSCs (hBMSCs) in vitro and in vivo.Materials and Methods: hBMSCs were isolated from human vertebral bone marrow during a vertebral surgery. To confirm the stem cell population in the isolated cell group, characterization of cells used in this study was performed using well established in vitro and in vivo assay models. The effect of FGF-2 (0, 2, 5, 20 ng/ml) treatment on biologic changes of characterization of hBMSCs was analyzed thoroughly. In order to investigate the effect of FGF-2 on the hBMSCs induced collagen tissue regeneration, in vitro insoluble/soluble collagen and corresponding hydroxyproline synthesis were assessed and real-time polymerase chain reaction (PCR) was performed using types of collagen and Lox (Lysyl oxidase) family genes. In vivo collagen formation was examined after hBMSCs were transplanted using an in vivo assay model for collagen tissue regeneration. After 8 weeks of healing, histologic and immunohistochemistry analysis were performed (n = 4).Results: hBMSCs population with the characteristics of MSCs (Mesenchymal Stem Cells) was present in isolated cells from bone marrow of human vertebrae. Effect of FGF-2 on hBMSCs showed results consistent with previous reports in terms of CFE (Colony Forming Efficiency), proliferation, and in vitro differentiation. The amount of insoluble/soluble collagen production was also significantly enhanced in hBMSCs expanded with FGF-2 compared to hBMSCs without FGF-2. Although the changes of expression pattern of collagen-related mRNA were different dependent on the type of specific gene, FGF-2 decreased collagen type I expression of hBMSCs while it increased collagen type III. Expression of all Lox family gene was enhanced following FGF-2 treatment. The histologic and immunohistochemistry results revealed that the collagen formed in vivo by hBMSCs showed more relevant amount and well-organized structure in the FGF-2 treated hBMSCs at 8 weeks (p< 0.05)Conclusion: FGF-2 facilitates the properties and collagen producing potency of hBMSCs, rendering them more suitable for collagen regeneration mediated wound healing by hBMSCs.ope

Jop shop 조기완료시간 및 납기지연시간의 최소화에 대한 연구

학위논문(석사)--서울대학교 대학원 :산업공학과,2000.Maste

(An) experimental study on the effects of dog's pulpal healing after cobalt-60 irradiation

치의학과/박사[한글] 두경부 방사선 처치 환자에 있어서 근관치료를 시행하는 주요목적은 발치를 하지 않고 보존하거나 발치를 가급한 연기시키기 위한 잠정적인 처치법으로 사용하는 것이 관례이다. 이에 저자는 방사선 조사를 받은 후 치수노출이 되였을 경우 그 치유기전에 관하여 연 구하고자 성견을 사용, cobalt-60을 조사한 군과 방사선 조사를 하지 않은 대조군으로 나누어 각기 직접치수복조술(Dycal**(R) 사용)을 시행한후 치수의 병리조직학적 변화를 관찰하여 다음과 같은 결론을 얻었다. 1. 수복성 상아질(reparative dentin)의 형성은 대조군에서 1주부터, 실험군Ⅰ과 Ⅱ에서는 2주부터 관찰되었다. 상아세관구조(dentinal tubule structure)는 대조군에서만 4주 째에 수가 적었고, 불규칙한 양상으로 나타났으며, 실험군Ⅰ, Ⅱ에서 모두 관찰되지 않았다. 2. 상아질 교(dentin bridge)의 연속성은 대조군, 실험군Ⅰ, Ⅱ 공히 3주부터 관찰되었다. 3. 치수조직내의 충혈 및 출혈은 공히 3주까지 관찰되었고 염증상은 대조군에서는 볼 수 없었으나 실험군Ⅰ, Ⅱ에서는 2주까지 관찰되었고, 실험군Ⅱ에서는 그 정도가 더 심했다. 4. 수산화칼슘이 치수조직내에 깊이 침입된 경우에는 치수조직의 국소적괴사가 관찰되었고 상아질 형성이 현저히 감소하는 양상을 보였다. [영문] Irradiation is frequently employed as the sole therapy for oral cancer. These irradiated patients presents peculiar and progressive dental problems. But there is entry scanty informations concerning specific approaches to endodontic treatment for head and neck cancer patients who have been subjected to tumorcidal doses of radiation therapy. The purpose of the present study was to determine the effects of cobalt-60 radiation on the pulpal healing of dogs after the direct pulp capping. As the experimental animals, 10 dogs (above 7-8 months after birth) were divided into 3 groups (Control, Group Ⅰ,group Ⅱ). The cobalt-60 was irradiated to the group Ⅰ and group Ⅱ each 1,009 and 1,562.5 rads as single dose. As the capping material Dycal**(R) (L.D. Caulk company)was selected. After the direct pulp capping the dogs were sacrified 1, 2, 3, 4, week interval and made the original slides cut with a thickness of 8 microns and stained with hematoxylin and eosin. After examination and comparision of all specimen, the results of this study were drawn as follows; 1. The formation of reparative dentin was observed from the 1st week in the Control group, the 2nd week in the Group Ⅰ & Ⅱ. The few and irregular table structure was appeared in the 4th week in the Control group only, but foiled in the Group Ⅰ & Ⅱ. 2. The continuity of dentin bridge was appeared in the 3rd neck in all group and the degeneration of odontoblast in the 1st week of the Group Ⅱ. 3. The congestion and hemorrhage in the pulp tissue were observed in all groups until 3rd week. The inflammation was appeared within the 2nd week in the Group Ⅰ and especially marked in the Group Ⅱ, but absent in the Control group. 4. In cases Dycal into the pulp tissue deeply, the local necrosis of pulp and decrease of dentin formation was observed.restrictio

(An) experimental study on the surface roughness of the composite resin

치의학과/석사[한글] 치아수복재로 사용되기 시작한 Composite resin은 약10년전부터 사용되어왔다. Composite resin의 실패의 주원인은 변색, 2차우식증, 마모 등으로 사료된다. 변색의 원인은 연마가 이상적으로 될 수 없으므로 거친표면에 음식물 잔사와 세균의 영향으로 변색을 초래하게 된다고 사료된다. 이 논문은 Composite resin에 있어서의 연마방법에 따른 표면거칠기의 효과를 알아보고자 임상에서 전치부에 많이 사용하는 Composite resin 중 Adaptio(Johnson & Johnson Company), Compo-T(Motloid Company), Composite(Shofu Company),Epolite 100(G-C Company) 를 선택하였다. 가공방법은 Mylar matrix하에서 중합반응을 일으킨 것과, 3가지의 연마기구 Mounted stone(Chaye Company), Silicone point # 13S(Shofu Company) 및 Aluminum oxide(Moyer company)를 사용하여 연마한 Composite resin의 표면을 roughness tester(Surftest-B)로써 표면거칠기를 측정하며 다음과 같은 결론을 얻었다. 1) 연마방법에 따른 표면거칠기의 산술평균과 표준편차는 Mylar matrix에서 26.50μ in ± 5.13, Mounted stone에서 117.90μ ± 5.98, Silicone point # 13S에서 138.10μ in ± 16.09, Aluminum oxide에서 175.00μ in ± 12.43으로 나타났다. 2) Mylar matrix에 의하여 경화된 Composite resin의 표면거칠기가 Mounted stone, Silicone point # 13S, Aluminum Oxide에 의하여 연마된 Composite resin의 표면거칠기보다 낮은 표면거칠기를 나타내었다. 3) 연마기구로 연마한 표면거칠기는 Mounted stone, Silicone point # 13S, Aluminum Oxide의 순으로 나타났다. [영문] To observe the effect of the polishing instruments on the composite resin restorations, the author has studied the surface roughness by means of the surface roughness tester (surftest-B) .The polishing instruments used in this study were the Mounted stone, the silicone point #135, the Aluminum oxide and the Mylar matrix. The composite resins were Adaptic, Compo-T, Composite and Epolite-100. The results obtined were as follows. 1. According to the polishing instruments, the arithmetic averages and standard errors of the surface roughness were the Mylar matrix (26.50 micro inch ±5.13), the Mounted stone (117.90 micro inch ± 5.98), the Silicone point #13 S (138.10 micro inch ± 16.09), the Aluminum oxide (175.00 micro inch ± 12.43). 2. The surface roughness of the composite resin polymerized under the Mylar matrix was smoother than thoses of the composite point # 13 S and the Aluminum oxide. 3. The smooth coders of the surface roughness ofthe polished composite resins were the Mounted stone, the Silicone point # 13 S and the Aluminum oxide.restrictio