국산 근접치료용 Ir-192 선원의 개발 및 실용화 동향

손광재,정동혁,Son, Kwang Jae,Jeong, Dong Hyeok 한국의학물리학회 2012 의학물리 Vol.23 No.4

최근 전 세계적인 원자로 시설의 감축으로 인한 수입 치료용 동위원소의 가격 상승으로 인하여 의료기관에서 근접치료기 운영에 문제가 되고 있다. 본 보고서에서는 국내에서 생산한 두 종류 Ir-192 선원(직경 4.5 mm와 1.1 mm)의 개발 과정과 기술 동향 대하여 제시하였다. 이 보고서의 내용이 근접치료기를 운영하는 의료기관에서 정책 수립에 도움이 되기를 바란다. Recently, there are difficulties in operating brachtherapy machine in the radiotherapy department because of increasing the source price with decreasing nuclear reactor in the world. The development and technical features of the Ir-192 HDR sources (4.5 mm, 1.1 mm in diameter) in Korea were described in this report. We expect that this report will be helpful for hospitals to make the long-term plan for operating and managing HDR brachytherapy machine.

적층판 이론을 이용한 용접부 각 변형량 해석에 관한 연구

손광재,양영수,최병익 대한용접접합학회 1999 대한용접·접합학회지 Vol.17 No.2

The problems of welding distortion in a welded structures are major concern in heavy industry. Weld-induced angular distortion's formula, composed weld parameter such as heat input and plate thickness, is developed analytically by the use of an elliptic cylindrical inclusion with an eigenstrain in an infinite laminated plate theory. The source of angular distortion in weldments is the plastic strains, which are caused by non-uniform temperature gradient. The distributions of the plastic strain corresponding eigenstrain are assumed by the use of Rosenthal's solution expressing thermal history. Comparison of calculated results with experimental data shows the accuracy and validity of the proposed method.

방사성동위원소의 생산과 응용 (전력회수를 중심으로)

손광재 한국자기학회 2014 한국자기학회 학술연구발표회 논문개요집 Vol.2014 No.11

우주 탐사에 원자력전지의 응용

손광재,홍진태,김종범,엄영랑,김진주,최상무 한국항공우주학회 2015 한국항공우주학회 학술발표회 논문집 Vol.2015 No.4

1950년대 중반부터 우주에서 원자력에너지를 이용하기 위한 연구들이 진행되었고, 그 결과 초기의 RTG들이 만들어져 우주에서 운용되기 시작하였다. 이 RTG들은 출력이 낮아 보조전원으로 사용되었으나 몇 가지 기술적인 진보로 다양한 임무에서 주전원의 역할을 수행하고 있다. 최근 RTG를 동력원으로 하는 우주선들이 태양계 외행성 탐사 및 태양과 지구궤도에서 여러 가지 탐사임무를 수행하고 있으며 화성과 달 착륙선의 동력원으로도 RTG가 사용되고 있다. 본 논문에서는 미국 및 러시아(구소련)을 중심으로 하는 우주탐사 선진국의 RTG 개발 및 이용현황, 우리나의 원자력전지 개발현황 및 전망에 대해 논의하였다. In the mid of 1950, basic researches had begun to find a way to use atomic energy in space exploration and first spacecrafts equipped RTG were started to launch. These low power RTGs were designed as auxiliary electricity supplier. But recently, RTG have been used as main power for many missions because of several technological progress. These days, RTG powered space probes are exploring deep space and inter-planetary mission. In this paper, we were discussing about development and application status of RTGs in U.S., Russia and Korea

신경회로망을 이용한 선상가열공정의 가열선 위치선정에 관한 연구

손광재,양영수,배강열 대한용접접합학회 2003 대한용접·접합학회지 Vol.21 No.4

Line heating is an effective and economical process for forming flat metal plates into three-dimensional shapes for plating of ships. Because the nature of the line heating process is a transient thermal process, followed by a thermo elastic plastic stress field, predicting deformed shapes of plate is very difficult and complex problem. In this paper, neural network model o3r solving the inverse problem of metal forming is proposed. The backpropagation neural network systems for determining line-heating positions from object shape of plate are reported in this paper. Two cases of the network are constructed-the first case has 18 lines which have different positions and directions and the second case has 10 parallel heating lines. The input data are vertical displacements of plate and the output data are selected heating lines. The train sets of neural network are obtained by using an analytical solution that predicts plate deformations in line heating process. This method shows the feasibility that the neural network can be used to determine the heating-line positions in line heating process.

고유변형율의 개념을 이용한 열가공공정 시 판 변형 예측

손광재,양영수,장상균 대한용접접합학회 2003 대한용접·접합학회지 Vol.21 No.1

In the present work, a formula for plate deformation produced by line heating, in terms of process parameters such as heat input and plate dimensions, is developed analytically using an eigenstrain concept. The residual deformation that was due to thermal process was depends on the magnitude and region of plastic strains at heating zone. The magnitude of plastic strains was determined by disk model and its region was calculated using the Rosenthal"s solution. The vertical displacement of the plate was analyzed by using an infinite laminated plate theory to consider a cuboidal inclusion with an eigenstrain. Comparison of the calculated results and experimental data shows the accuracy and validity of proposed method.thod.

하나로를 이용한 비파괴검사용 169Yb 저에너지 밀봉선원 개발

손광재,홍순복,장경덕,한현수,박울재,이준식,서기석,한인수,조운갑,이성식 한국비파괴검사학회 2008 한국비파괴검사학회지 Vol.28 No.1

169Yb industrial NDT sealed sources were developed by using Yb2O3 pellets as the target and demonstrated for their performance. To produce the pellets, optimal compacting and sintering conditions were determined experimentally. Source holders for 169Yb were designed and fabricated. After assembling an active source produced from HANARO with the developed source holder, a demonstration experiment was performed to compare the quality of the radiographs from 192Ir and soft X-rays. This demonstration study showed that the developed 169Yb produced better radiographs than 192Ir for a carbon steel with less than a 4mm thickness. 본 연구에서는 하나로 및 동위원소생산시설을 활용하여 비파괴 검사에 사용되는 169Yb 선원의 생산기술을 개발하였다. 천연 존재비 0.14%의 168Yb을 20% 까지 농축한 Yb2O3 분말을 표적물질로 사용하였고 이 물질의 방사화를 위하여 펠릿 성형기술 및 장치를 개발하였다. 중성자 조사를 위한 표적캡슐 및 기존 192Ir 선원 조사기에 사용이 가능한 선원 어셈블리를 설계·제작하였다. 또한, 하나로를 이용하여 약 5 Ci의 방사능 강도를 갖는 시험용 선원을 제작하여 192Ir 선원과 비파괴검사 성능을 비교 평가하여 선원의 우수함을 확인하였고 선원캡슐의 안전성시험을 실시하여 캡슐의 안전성을 검증하였다.

하나로 LH에서 방사성동위원소 생산을 위한 중성자 조사장비 개발

손광재,한현수,홍순복,박울재,이준식,박종원,Son, Gwang-Jae,Han, Hyeon-Su,Hong, Sun-Bok,Park, Ul-Jae,Lee, Jun-Sik,Park, Jong-Won 한국동위원소협회 2004 동위원소회보 Vol.19 No.4

차체 저항 점 용접부 피로수명 예측

손광재,양영수,조성규,장상균 대한용접접합학회 2002 대한용접·접합학회지 Vol.20 No.2

When the vehicle travels in an actual road, resistance spot weldments of the vehicle structure are exposed to complex loading state. Since the fatigue strength in resistance spot weldment of vehicle body can be determined by effect of residual stresses and loading state of driving, estimating actual loading state and considering residual stress effect are needed. In this study, Fatigue stress-fatigue life relation concerned residual stress effect was obtained by thermo elastic plastic finite element analysis. And applied loading in resistance spot weldments of vehicle body was calculated by dynamic analysis. Presumption of fatigue life was performed using proposed method

고농축 표적을 이용한 비파괴검사용 192Ir 미세초점선원 개발

손광재,홍순복,장경덕,한현수,박울재,이준식,김동학,한근대,박춘득 한국비파괴검사학회 2007 한국비파괴검사학회지 Vol.27 No.1

192Ir small-focal source has been developed by using the HANARO reactor and the radioisotope production facility at the Korea Atomic Energy Research Institute (KAERI). The small-focal source with the dimension of 0.5mm in diameter and 0.5mm in length was fabricated as an aluminum-encapsulated form by a specially designed pressing equipment. For the estimation of the radioactivity, neutron self-shielding and -ray self-absorption effects on the measured activity was considered. From this estimation, it is realized that 192Ir small-focal sources over 3 Ci activities can be produced from the HANARO. Field performance tests were performed by using a conventional source and the developed source to take images of a computer CPU and a piece of a carbon steel. The small-focal source showed better penetration sensitivity and geometrical sharpness than the conventional source does. It is concluded from the tests that the focal dimension of this source is small enough to maximize geometrical sharpness in the image taking for the close proximity shots, pipeline crawler applications and contact radiography. 하나로와 동위원소 생산시설을 활용하여 비파괴검사용 192Ir 미세초점선원의 생산기술을 개발하였고 현장적용시험을 통하여 개발된 제품의 성능을 확인하였다. 직경 0.5mm × 높이 0.5mm인 선원의 개발을 위해 알루미늄 캡슐 압착 방법 및 장치를 개발하여 표적을 제작하였으며, 하나로를 이용한 방사능 생성량을 평가한 결과 약 3.0 Ci 방사능의 선원 제조가 가능함을 확인하였다. 또한 컴퓨터 CPU 및 탄소강에 대한 비파괴검사를 실시하여 투과도계 감도 및 기하학적 불선명도가 비교 대상 선원에 비해 우수함을 확인하였다. 이 선원의 초점크기는 기존의 선원에 비해 매우 작기 때문에 근접 및 접촉촬영과 튜브-튜브시트 용접부의 비파괴검사에 있어 기하학적 불선명도를 최소화 할 수 있을 것이다.주요용어: 미세초점선원, 방사선투과검사, 이리듐-192, 하나로