• 대한전자공학회논문지TC
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• 제47권4호
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• pp.63-72
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• 2010

본 논문에서는 LR-WPAN을 위한 새로운 인증 프로토콜을 제안한다. 제안하는 프로토콜에서는 계층 구조를 이용한 인증을 수행하여 인증의 안전성 및 신뢰성을 확보한다. 또한 계층 구조에서 나타나는 효율성 감소 및 denial of service(DoS) 공격에 대한 취약점을 해결하기 위하여 정보 교환 횟수를 줄여 적합한 사용자 및 적합하지 않은 사용자를 인증할 때의 효율성을 제공하고 Local Authentication Key를 이용하여 트러스트 센터(trust center)와 참여자 기기 및 부모 노드와 참여자 기기 사이의 신뢰 관계를 확인한다. 제안하는 프로토콜의 성능 평가를 위하여 security 분석을 통해 안전성을 평가하며 GNY 분석을 통해 프로토콜의 신뢰성을 평가한다. 또한 DoS 공격 발생 시 네트워크에 참여중인 기기의 메시지 전송 횟수를 분석하여 DoS 공격에 대한 프로토콜의 안전성을 평가한다. 마지막으로 현재 LR-WPAN을 위한 표준인 ZigBee의 인증 프로토콜과 제안한 프로토콜을 LR-WPAN 기기에 구현하여 인증과정에 필요한 시간을 측정하고, 측정된 시간을 바탕으로 각 홉 수 별로 인증 완료 시간을 분석한다. 이 과정을 통하여 제안한 프로토콜이 기존의 인증 프로토콜보다 보안성이 강화되며 인증 완료시간을 홉 수에 따라 최대 30% 줄임을 확인하였다.

• 치위생과학회지
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• 제3권1호
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• pp.1-4
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• 2003

본 고는 치위생 임상업무를 수행하는 과정에서 발생할 수 있는 외상성 치은 손상에 대처하기 위한 방법으로서 조직접착제의 활용 방안에 대해 검토하고자 하였다. 시아노아크릴레이트 조직접착제는 조직 표층의 열창을 기존 봉합법에 의하지 않고 화학물질에 의한 접착 방식으로 폐쇄하기 위한 용도로서 그 동안 구강외과나 치주수술 분야에서 그 응용이 모색되어 왔다. 치과위생사가 치석제거 및 치근활택술 등의 시술 과정에서 부적절하거나 과도한 기구조작에 의해 치은이나 구강점막에 열창이 초래될 수 있다. 이러한 상황에 발생하였을 경우, 조직접착제를 이용하여 열창을 폐쇄하면 매우 효과적이며 단순하고 편리하다. 조직접착제는 n-butyl-2-cyanoacrylate로 구성되어 있으며, 조직의 수분과 접촉하면 빠르게 중합되어 접착력을 나타낸다. 조직접착제를 이용한 치은열창의 처치는 그 심미적 결과가 양호하며, 추가적인 조직 손상이 없을 뿐 아니라 시술 방법이 간단하여 시간이 적게 소요된다. 또한 국소마취가 필요치 않으며, 창상 소독이나 봉합사 제거를 위해 환자가 다시 내원하지 않아도 되는 등의 여러 임상적 장점이 있다. 창상의 감염 방지나 지혈 작용 등에도 효과적이다. 조직접착제는 치위생 임상에서 발생할 수 있는 조직손상에 대한 처치법으로서 환자나 치과위생사 모두에게 유용하게 활용될 수 있다.

• 터널과지하공간
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• 제12권3호
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• pp.142-151
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• 2002

대전 식품냉동저장창고 파일럿 공동주위의 거리에 따른 비정상상태의 온도 분포를 산정하기 위해 Claesson(2001)의 해석해 및 Dirichlet과 Neuman 내부 경계조건을 갖는 수치모델들을 검토하였다. 온도 강하 단계동안 일정 표면 온도 경계조건에 기초하고 있는 Claesson의 해석해를 활용한 결과, 실제 암반에서의 온도 계측결과를 오차 평균 0.89$^{\circ}C$ 수준으로서 비교적 정확히 예측할 수 있었는데, $0^{\circ}C$근처의 실험실 암석 열물성을 입력하였고 현지 암반 조건을 표현하기 위한 특별한 물성 보정을 하지 않았다. 내부 공동 암반 벽면을 통한 열유속을 갖는 수치해석의 경우, 대류 열전달계수와 공동 내부 온도가 냉각시간에 따라 변화하기 때문에 경계조건을 가하기 어려운 단점을 극복하기 위해 새로운 경계조건 설정 기법을 제안하였다. 그 결과 오차 평균 1.58$^{\circ}C$의 수준으로서 온도 계측치와 부합하였다. 또한 공동 벽면에서 고정 온도 조건을 갖는 수치해와 비교하였다. 마지막으로 Claesson의 해석해 및 다양한 내부 경계조건을 갖는 수치모델을 활용하여, 공동 주변의 온도 분포를 정확히 예측할 수 있는 일련의 해석 단계 프로그램을 제안하였다.

• Journal of Chest Surgery
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• 제32권2호
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• pp.175-180
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• 1999

배경: 연세대학교 영동세브란스병원 흉부외과에서 1992년 다한증환자에서 흉곽내시경을 이용한 교감신경절제술을 시행한이래로 교감신경절제술은 원발성 다한증환자에서 간편하고 효과적인 치료방법이다. 수술직후의 만족도는 94∼98%로 보고되는 반면 6개월이 지난 장기 추적조사에서의 만족도는 약 66%로 보고되고 있고 만족도가 떨어지는 원인으로 보상성다한증에 의한 일상생활의 불편이 가장큰 요인이다. 대상 및 방법:연세대학교 영동세브란스 흉부외과에서 1992년부터 1998년 까지 783례의 다한증 수술환자중 T2 교감신경절단술 환자 89명(1군), T2 교감신경절제술 88명(2군), T2-4 교감신경절제술 138명(3군)을 대상으로 각각의 수술방법에 따라 보상상다한증의 발생 빈도와 정도을 비교하였다. 보상성다한증의 정도를 1, 없다(Absence); 2, 약간있다(Mild); 3, 눈으로 보일정도이나 생활에 지장이 없다(Embarrassing); 4, 생활에 불편할정도로 많으며 하루에 2-3번내의를 갈아입는다(Disabling)로 구분하였다. 결과: 모든 환자에서 증상이 소실되었으며 전체적인 보상성 다한증의 발생율은 1군이 64%, 2군이 73.8%, 3군이 87.8%였으며 Embarrassing 과 Disabling 의 경우 1군 15.7%, 2군 32.2%, 3군 58.0% 로 수술방법에 따른 보상성 다한증의 발생과 정도에 차이가 있었다(p<0.05) 결론: 이와 같은 결과로 보상성 다한증의 발생과 정도는 교감신경절제의 범위와 밀접한 연관이 있으며 보상성 다한증을 줄이고 장기 추적조사에서의 만족도를 증가 시키기 위해서는 T2 교감신경절제술 보다는 T2 교감신경절단술이 종 더 유용할 것으로 생각됩니다.

• Journal of Chest Surgery
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• 제33권1호
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• pp.38-44
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• 2000

Background: We analyzed the result of the "Off-Pump" Coronary Artery Bypass grafting (OPCAB) performed to minimize inflammatory responses to cardiopulmonary bypass and myocardial ischemia during the aortic cross-clamp period. Material and Method : The preoperative diagnosis operative procedure mortality complication and postoperative course of the 50 patients who underwent OPCAB between January 1998 and September 1998 were analyzed. There were 34 males and 16 females with mean age of 60$\pm$9 years. Preoperative clinical diagnoses were unstable angina in 31(62%) stable angina in 16(32%) and clinical diagnoses were unstable angina in 31(62%) stable angina in 16(32%) and postinfarction angina in 3(6%) patients. Preoperative angiographic diagnoses were three-vessel disease in 25(50%) two-vessel disease in 5(10%) one-vessel disease in 7(14%) and left main disease in 13(26%) patients. There were elective operation in 37 cases and urgent operation in 13 cases. Result: The mean number of grafts was 3.2$\pm$1.2 per patient. Grafts used were unilateral internal thoracic artery in 43 greater saphenous vein in 37 radial artery in 7 bilateral internal thoracic arteries in 4 and right gastroepiploic artery in 2 cases Forty sequential anastomoses were performed in 18 cases. Vessels accessed were left anterior descending artery in 48 diagonal branch in 41 obtuse marginal branch in 30 right coronary artery in 24 posterior descending artery in 9 ramus intermedius in 5 and posterolateral branch in 5 anastomoses. Predischarge coronary angiography performed in 44 patients demonstrated the patency rate of 89.5%(128/143) Operative mortality was 2%(1/150) Postoperative complications were arrhythmia in 5 graft occlusion that needed reoperation in 4. perioperative myocardial infarction in 2 femoral artery thromboembolism developed after the application of IABP in 1 postoperative transient delirium in 1 peripheral compression neuropathy in 1 case. Sixteen patients(32%) were extubated at the operating room and the other patients were extubated at the mean 13$\pm$20 hours after the operation. Mean duration of stay in intensive care unit was 49$\pm$46 hours. Thirteen patients(26%) required blood transfusions perioperatively and the amount of perioperative blood transfusion was mean 0.70$\pm$1.36 pack/patient. Conclusion: OPCAB is suggested to be the ideal technique with less postoperative complication less hospitalization time and less cost.less cost.

• Journal of Radiation Protection and Research
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• 제20권1호
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• pp.25-36
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• 1995

The purpose of this research is to develop stereotactic localization and radiation measurement system for the efficient and precise radiosurgery. The algorithm to obtain a 3-D stereotactic coordinates of the target has been developed using a Fisher CT or angio localization. The procedure of stereotactic localization was programmed with PC computer, and consists of three steps: (1) transferring patient images into PC; (2) marking the position of target and reference points of the localizer from the patient image; (3) computing the stereotactic 3-D coordinates of target associated with position information of localizer. Coordinate transformation was quickly done on a real time base. The difference of coordinates computed from between Angio and CT localization method was within 2 mm, which could be generally accepted for the reliability of the localization system developed. We measured dose distribution in small fields of NEC 6 MVX linear accelerator using various detector; ion chamber, film, diode. Specific quantities measured include output factor, percent depth dose (PDD), tissue maximum ratio (TMR), off-axis ratio (OAR). There was small variation of measured data according to the different kinds of detectors used. The overall trends of measured beam data were similar enough to rely on our measurement. The measurement was performed with the use of hand-made spherical water phantom and film for standard arc set-up. We obtained the dose distribution as we expected. In conclusion, PC-based 3-D stereotactic localization system was developed to determine the stereotactic coordinate of the target. A convenient technique for the small field measurement was demonstrated. Those methods will be much helpful for the stereotactic radiosurgery.

• 지역사회간호학회지
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• 제12권2호
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• pp.532-546
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• 2001

This report is the result of interim evaluation of a health promotion project which was operated by a public health center of K Gu in the year of 2000. It evaluated the aspects of the aim of a project, a target group. and adequacy and appropriateness of a approaching strategy by considering data of public health center's self-evaluation, and guidelines of a group assigned to evaluate the project. The way of evaluation was dividing the project into a colligated evaluation and a evaluation by projects in the aspects of the structure, the procedure. and the result of a result. Through this. a device to improve the health improvement project was derived. The target data for evaluation was the second data and data of self-evaluation, reported data, membership register data of a health management. and interview materials with the people in charge by projects that are all collected as a project management documents. The result of evaluation is stated below. 1. Main purpose of a health promotion project is building a environment of healthy life practicing and providing information through various ways to increase the rate of practicing healthy life. Through overall project. the ultimate purpose and definite purpose were same, however, it was not quite satisfied to offer planning of a time, and a target amount in detailed strategy. As the purpose was to build environment of healthy life practicing. most of the projects had the whole community citizen as a target group. That made difficult to operate detailed projects. so the result was hard to estimate as much as the effort put into it. Also, there were too many kinds of projects and target groups to be equal to by the human source of a health promotion project team. so we were just bent on operating a project. and could not prepare for the evaluation. As the most of former evaluation of public health service was just counting number of the objects, the new way of evaluating a project wasn't familiar to us. so the evaluation of a detailed project cannot be done well. Techniques and advices needed for all of these things weren't offered appropriately. For the forward direction of unfolding project. it is desirable to operate project by selecting focused target and considering a strategy of evaluation as a strategy of reasonable spread. The evaluation of the project became difficult as participation of citizen for it was poor. So, approach strategy that can lead the motivation of community citizen should be derived. 2. For the continuation of a health promotion project, technical assistance system. description of a field in charge, and arrangement of the amount of task should be developed as a central level. Furthermore, as the health promotion project focus on behavioral modification program whose purpose is to lessen dangerous factors. the public health service model which is incorporated with former project should be developed and spread out in the field for the object-centered project plan.

• Journal of Gastric Cancer
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• 제1권1호
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• pp.60-63
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• 2001

Purpose: The aim of this study was to analyze the clinical and the histopathological characteristics of mucosa associated lymphoid tissue (MALT) lymphomas in the stomach. Materials and Methods: We retrospectively reviewed the medical records of 22 patients who had been treated at Samsung Medical Center from Jan. 1995 to Sep. 2000 and who had been pathologically proven to have a MALT lymphoma. The factors we analyzed were operative procedure, tumor stage, and histopathological characteristics. Results: Of 3658 patients with a gastric malignancy, 22 patients proved to have a MALT lymphoma ($0.6\%$). There were 7 men and 15 women whose ages ranged from 25 years to 70 years (mean, 48.8 years). Forteen cases were located in the antrum, 4 ($18\%$) in the body and 4 ($18\%$) in the fundus or the high body. Nineteen of these patients were managed with total gastrectomy and splenectomy and 3 with radical subtotal gastrectomy. Histopathologically the tumor was limited to the mucosa in 3 patients ($1.36\%$), to the submucosa in 13 ($59.1\%$) and extended to the muscularis propria in 6 ($27.3\%$). Lymph node involvement was seen in 12 patients ($54.6\%$). There was no splenic or hepatic involvement. Bone marrow involvement was not seen in any patients. H. pylori was identified in 11 patients (50$\%$). During the mean follow-up period of 32.7 months, there were no reports of tumor recurrence or death. Conclusion: MALT lymphomas rarely disseminate by the time of diagnosis and rarely involve the bone marrow. Lymph node involvement is relatively high and a total gastrectomy is effective in managing patients with a MALT lymphoma.

• 한국공간구조학회논문집
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• 제11권2호
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• pp.129-138
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• 2011

지하공사는 상부층의 구조물과 연계된 시공순서에 따라 Bottom-Up공법, Up-Up공법 그리고 Top-Down 공법으로 대별할 수 있다. 탑다운 공법을 사용하면 건물의 본구조를 흙막이지보공으로 이용하면서 상층에서 하층으로 굴착과 구체구축을 반복하여 시공함으로써 인접구조물이나 주변 지반의 변위를 극소화 시킬 수 있다. 이는 토류벽의 안정성이 높으며, 각층의 바닥슬래브를 작업공간으로 사용하여 도심지 공사에서 작업장 확보가 용이하다. 그러나 굴토작업이 슬래브 하부에서 진행되므로 작업 능률 및 작업환경이 저하되고, 어스앵커 공법보다 경제성이 없다는 이유로 다소 회피하는 경우가 종종있다. 따라서 본 논문에서는 터파기 공사는 세미오픈컷 공법을 적용하고 흙막이 공법에는 지하연속벽(슬러리월)을 그리고 지보공으로는 C.W.S공법을 적용한 역타공법으로 대상현장을 중심으로 기존 역타공법과 경제성, 공사기간 및 작업성 등을 분석 제시하였다. 토사운반 및 철골설치공사 작업의 용이성과 PRD 공사의 정밀도 향상 등의 품질관리가 우수하며, 공기단축이 가능하였다.

• Journal of Periodontal and Implant Science
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• 제33권1호
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• pp.61-77
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• 2003

The major goals of periodontal therapy are the functional regeneration of periodontal supporting structures already destructed by periodontal disease as well as the reduction of signs and symptoms of progressive periodontal disease. There have been many efforts to develop materials and therapeutic methods to promote periodontal wound healing. Bone graft & guided tissue are being used for the regeneration of destroyed periodontium these days. Non-resorbable membranes were used for Guided tissue regeneration in early days, however more researches are focused on resorbable membranes these days. The aim of this study is to evaluate the osteogenesis of paradioxanone membrane on the calvarial critical size defect in Sprague Dawley rats. An 8 mm diameter surgical defect was produced with a trephine bur in the area of the midsagittal suture. The rats were divided into three groups: Untreated control group, Biomesh(R) group and paradioxanone group. The animals were sacrificed at 4, 8 and 12 weeks after surgical procedure. The specimens were examined by histologic, histomorphometric analyses. The results are as follows: 1. In histological view on Biomesh(R), no visible signs of resorption was observed at 4 weeks but progressive resorption was observed at 8 weeks through 12 weeks. Paradioxanone membrane expanded at 4 weeks, and rapid resorption was observed at 8 weeks. In both the membranes, inflammatory cells were observed around them. Inflammatory cells decreased with time but were still present at 12 weeks. More inflammatory cells were observed in paradioxanone membranes than in Biomesh(R) membrane. 2. The area of newly formed bone in the defects were 0.001${\pm}$0.001, 0.006${\pm}$0.005, 0.002${\pm}$0.003 at the 4 weeks, 0.021${\pm}$0.020, 0.133${\pm}$0.073, 0.118${\pm}$0.070 at the 8 weeks and 0.163${\pm}$0.067, 0.500${\pm}$0.197, 0.487${\pm}$0.214 at the 12 weeks in the control group, Biomesh(R) group and experimental group respectively. Compared to the control group, Biomesh(R) group displayed significant differences at 4,8, and 12 weeks and the paradioxanone group at 8 and 12 weeks.(P<0.05)