광섬유 방사선 센서와 EBT 필름을 이용한 심부선량 백분율 측정 및 비교

조동현,장경원,유욱재,신상훈,이봉수,문주현,박병기 제주대학교 방사선응용과학연구소 2008 방사선응용과학연구소논문집 Vol.22 No.-

In this study, fiber-optic sensor is fabricated to measure PDD of CLINAC. As a scintillating light generated by a high energy X-ray from the medical LINAC is measured using photo diode amp system, It is expected that a high-resolution, real-time fiber-optic dosimeter for medical LINAC can be developed.

전방 또는 전측방 흉수 종양 수술에서 후측방도달법

조경석,박춘근,성재훈,허필우,박춘근,백민우,김달수,강준기 대한신경외과학회 1997 Journal of Korean neurosurgical society Vol.26 No.5

기본 모드에서 동작하는 비동기 순차 회로의 시험 벡터 생성

趙庚衍,李宰勳,閔炯福 성균관대학교 1998 학술회의지원논문목록집 Vol.1998 No.-

비동기 순차 회로에 대한 시험 벡터를 생성하는 문제는 매우 어려운 문제로 남아 있다. 현재까지 이 문제 에 대한 알고리즘은 거의 없었다. 그리고, 기존의 접근 방식은 시험 벡터를 생성하는 동안에는 피이드백 루프를 절단하여 그 곳에 플립플롭이 있는 것처럼 가정하고 시험 벡터를 생성하는 방식이었다. 그래서, 기존의 알고리즘은 동기 순차 회로용 시험 벡터 생성 알고리즘과 매우 유사하였다. 이것은 시험 벡터를 생성할 때에는 비동기 순차회로를 동기 순차 회로로 가정하고 시험 벡터를 생성한다는 것을 의미한다. 그러므로, 생성된 시험 벡터가 비동기 순차 회로에 적용되었을 때, 대상 결함을 검출하지 못할 수도 있다는 것을 나타낸다. 본 논문에서는 비동기 순차 회로에 대한 시험 벡터를 생성할 수 있는 알고리즘을 제시하였다. 본 논문에서 제안된 알고리즘을 적용하여 생성된 시험 벡터는 임계레이스(critical race) 문제와 순환(oscillation) 문제의 발생을 최소로 하면서 비동기 순차 회로의 결함을 검출할 수 있다. 그리고, 본 논문에서 제안된 알고리즘을 적용하여 생성된 시험 벡터는 비동기 순차 회로에 대해서 대상 결함을 검출하는 것이 보장된다. Generating test patterns for asynchronous sequential circuits remains to be a very difficult problem. There are few algorithms for this problem, and previous works cut feedback loops, and insert synchronous flip-flops in the feedback loops during ATPG. The conventional algorithms are similar to the algorithms for synchronous sequential circuits. This means that the conventional algorithms generate test patterns by modeling asynchronous sequential circuits as synchronous sequential circuits. So, test patterns generated by those algorithms may not detect target faults when the test patterns are applied to the asynchronous sequential circuit under test. In this paper an algorithm is presented to generate test patterns for asynchronous squential circuits. Test patterns generated by the algorithm can detect tasget faults for asynchronous sequential circuits with the minimal possibility of critical race problem and oscillation. And it is guaranteed that the test patterns generated by the algorithm will detect taraet faults.

스캔 설계 법칙 검사에 관한 연구

이재훈,김형국,조경연,임동욱,민형복 成均館大學校 科學技術硏究所 1997 論文集 Vol.48 No.2

Since testing of digital circuit is becoming increasingly important, many methodologies have been introduced to enhance design for testability (DFT). DFT was taken into account in the automated test procedure and improved reliability of the design. Both tasks are well suited for scan rule checker. This paper presents a scan rule checker for gate level digital circuits. The scan rule checker deals with basic rule check, basic scan rule check, muxed scan rule check, clocked scan rule check and lssd. Scan design informations were represented in the configuration file and libraries were modeled for the scan rule checker. It is an efficient way for the design for testability methodology.

건축공사시방서에서의 KS규격의 국제인증방안에 관한 연구

김경식,이재섭,김용수,이규진,조용훈,최완철,전재열,이현수,구재동,이기환 대한건축학회 2004 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.24 No.1

The purpose of this research is make out construction specifications for International Construction. Using off-shore products incur cost increase and longer delivery term of construction. and inconvenient on International Construction. Expand the range of additional local products conforming to performance. Life Cycle Cost. maintainability. operability. user's acceptability, etc.. And this study is suggest the standard formats and the techniques for construction specification.

고차원 색인 구조를 위한 효율적인 벌크 로딩 알고리즘

복경수,이석희,유재수,조기형 충북대학교 컴퓨터 정보통신 연구소 2000 컴퓨터정보통신연구 Vol.8 No.1

고차원 색인 구조를 위한 기존의 벌크 로딩 알고리즘은 색인 구성 시간과 검색 성능 모두를 향상시키지 못하는 문제점을 갖는다. 이 논문은 이와 같은 문제점을 해결한 대량의 고차원 데이터에 대한 색인 구조를 위한 새로운 벌크 로딩 알고리즘을 제안한다. 제안하는 알고리즘은 색인을 구성하는 시간을 단축시키기 위해 전체 데이터 집합을 정렬하는 것이 아니라 데이터의 특성을 파악하여 피벗값에 따라 분할하는 기법을 이용한다. 또한 검색 성능을 향상 시키기 위해 데이터들의 분포 특성에 따라 분할 위치를 선택한다. 제안하는 알고리즘에 대한 우수성을 입증하기 위해 실험을 통해 기존에 제안된 알고리즘과 색인 구성 시간 및 검색 성능을 비교한다. Existing bulk loading algorithms for high-dimensional index structures suffer from improving both index construction time and retrieval performance. In this paper, we propose an efficient bulk loading algorithm to construct high dimensional index structures for large data set that overcomes the problem. Although several bulk loading algorithms have been proposed for this purpose, none of them improve both construction time and search performance. To improve the construction time, we don't sort whole data set and use bisection algorithm that divides the whole data set or a subset into two partitions according to the specific pivot value. Also, we improve the search performance by selecting split positions according to the distribution properties of the data set. In order to show superiority of the proposed algorithm, we compare it with existing algorithms in terms of search time and construction time through experiments.

친수성 Polyvinylsiloxane 인상재의 putty와 light body의 결합강도

강재경,김경남,조리라,정경호 대한치과기재학회 2000 대한치과재료학회지 Vol.27 No.4

Polyvinylsiloxane is the most accurate and dimensionally stable material among the dental impression materials which replicate the teeth and oral tissues. There are two methods for taking impressions with the polyvinylsiloxane: one step simultaneous polymerization; and putty/wash two step reline technique. The purpose of this study was to evaluate tensile bond strength between putty and wash material under the conditions of contamination with saliva or water at taking impression by putty/wash technique. The materials used in this study were 4 hydrophilic polvinylysiloxane impression materials of putty and light body type(Perfect-F, Handae Chemical, Korea; Contrast, VOCO, Germany; Exaflex and Examix, GC, Japan; Express and Imprint Ⅱ, 3M, U.S.A.). First, putty material filled in one perforated metal mold with diameter of 15 ㎜ and height of 19 ㎜ was set, and it was bonded with light body material filled in other paired metal mold before setting. Tensile bond strength was measured at a cross-head speed of 300 ㎜/min by universal testing machine (Instron 6022, Instron Co., U.K.) after 10 minutes from the joining two mold in order to set completely. As results, tensile bond strength of Contrast, Examix and Perfect-F showed no significant difference with control group on contamination with saliva or water, and it showed cohesive failure in the light body. However, Imprint Ⅱ showed the highest strength among these tested materials and showed adhesive failure at 5 specimens in the case of contamination with saliva and 4 specimens with water. From the results of this study, each product use possible cross bond and the tensile bond strength of some materials showed lower value on contamination with saliva.

치료용 방사선의 입사각에 따른 광섬유 방사선량계의 체렌코프 빛 측정 및 분석

장경원,조동현,유욱재,신상훈,서정기,이봉수,박병기,문주현 제주대학교 방사선응용과학연구소 2008 방사선응용과학연구소논문집 Vol.22 No.-

In this study, we have measured scintillating light generated in a fiber-optic dosimeter by high energy photon and electron beams using a charge-coupled device. The intensity of Cerenkov lights are also measured and characterized as functions of incident angles and energies of the high energy beams from a clinical linear accelerator. To minimize or remove Cerenkov light, a simple subtraction method using a background optical fiber and wavelength discrimination method using optical filters are investigated. Also, the intensities of Cerenkov light induced by high energy photon and electron beams are compared.

임신 중 고혈압성 질환에 대한 임상적 고찰

김경철,정명철,김호성,조민형,고재환,김용봉 白中央醫療院 2005 仁濟醫學 Vol.26 No.1

Objective: The aim of this study was to investigate the clinical charact eristics of pregnancy induced hypertension(PIH). Methods: We retrospectively evaluated the clinical characteristics through the collected data of 176 PIH cases treated at Seoul Paik hospital from March 1995 to December 2002. Results: The proportions of severe PIH, mild PIH, and chronic hypertension were 70%, 24%, and 6% of the cases, respectively. According to maternal age, the highest rate of 45% was noted in the group of 26-30 years of age. The rate of cesarean(80%) was higher than the rate of vaginal delivery(20%). The blood pressure was controlled by hydralazine for 70% of the patients. The rate of single gestation was 90%. The birthweight of 20% of the newborn were 2500gm or more. The anemia, twin pregnancy, postpartum hemorrhage, pulmonary edema, and infection were found in 30%, 10%, 3%, 2%, and 1% of the PIH patients, respectively. In respect of the perinatal complications, the rates of low birth weight, stillbirth, and neonatal death were 80%, 3%, and 1%, respectively. Conclusion: We were able to decrease the mortality and morbidity of PIH patients and neonates with strict antenatal care and proper treatment.

특발성 자발성 신장 파열 1예

윤재철,김원,조규종,홍정석,이미우,장성은,오세현,임경수 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Primary aldosteronism is a syndrome characterized by hypertension, hypokalemia, suppressed plasma renin activity, and elevated serum aldosterone levels. Conn first described it 1955 in association with adrenal cortical adenoma(Conn's syndrome). Today, it can be divided into at least six distinctive sub-groups. The diagnosis of primary aldosteronism is usually suspected when the patient presents with poorly controlled hypertension with hypokalemia. The main issues in the evaluation of primary aldosteronism are to differentiate an adenoma from hyperplasia and to localize the adenoma. Basic hormonal studies and computed tomographic(CT) scanning can be used effectively for that differentiation. An adenoma is one of a few potentially curable forms of hypertension, and it is best treated by removing the adrenal tumor. We experienced a case of a typical adrenal adenoma. The patient was a 37-year-old male who had experienced in both his legs over a period of several days a weakness due to hypokalemia. He was diagnosed using basic hormonal studies and adrenal CT scanning. After, he received laparoscopic adrenalectomy and was discharged with improved condition.