• Radiation Oncology Journal
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• v.20 no.2
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• pp.165-171
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• 2002

Purpose : In order to perform craniospinal irradiation (CSI) in the supine position on patients who are unable to lie in the prone position, a new simulation technique using a CT simulator was developed and its availability was evaluated. Materials and Method : A CT simulator and a 3-D conformal treatment planning system were used to develop CSI in the supine position. The head and neck were immobilized with a thermoplastic mask in the supine position and the entire body was immobilized with a Vac-Loc. A volumetrie image was then obtained using the CT simulator. In order to improve the reproducibility of the patients' setup, datum lines and points were marked on the head and the body. Virtual fluoroscopy was peformed with the removal of visual obstacles such as the treatment table or the immobilization devices. After the virtual simulation, the treatment isocenters of each field were marked on the body and the immobilization devices at the conventional simulation room. Each treatment field was confirmed by comparing the fluoroscopy images with the digitally reconstructed radiography (DRR)/digitally composite radiography (DCR) images from the virtual simulation. The port verification films from the first treatment were also compared with the DRR/DCR images for a geometrical verification. Results : CSI in the supine position was successfully peformed in 9 patients. It required less than 20 minutes to construct the immobilization device and to obtain the whole body volumetric images. This made it possible to not only reduce the patients' inconvenience, but also to eliminate the position change variables during the long conventional simulation process. In addition, by obtaining the CT volumetric image, critical organs, such as the eyeballs and spinal cord, were better defined, and the accuracy of the port designs and shielding was improved. The differences between the DRRs and the portal films were less than 3 mm in the vertebral contour. Conclusion : CSI in the supine position is feasible in patients who cannot lie on prone position, such as pediatric patienta under the age of 4 years, patients with a poor general condition, or patients with a tracheostomy.

• Journal of KSNVE
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• v.3 no.4
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• pp.293-299
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• 1993

최근 토목, 건축재료 및 시공기술의 발전과 더불어 컴퓨터를 이용한 해석 기법의 개발, 경제규모의 확대, 주변환경과의 조화 및 미적감가의 끊임없는 추구는 구조물의 장대화, 연성화, 다양화는 물론 구조감쇠율의 감소 등을 가져옴으로서 바람에 의한 동적 거동의 영향이 증대되어 이에 대한 검토의 중요성이 크게 부각되기 시작하였다. 특히, 최근들어 활발히 계획, 공사중인 여러 현수교, 사장교 구조물 중 시공단계로서의 독립 tower, 발전소의 장대 굴뚝, 고층건물, 전망 tower, 공항 관제 탑 등이 좋은 예이다. 따라서 이들 구조물의 설계과정에서 제안된 여러형태의 진동 제어 방법중 수동 감쇠장치에 대하여 소개하기로 한다. 감쇠장치는 직접 외부에 부착 하는 강제 감쇠장치와 소량의 질량, 스프링과 감쇠장치들을 조합하여 부착하는 수동 감쇠장치가 있다. 수동감쇠장치는 소규모로서 유지보수가 거의 필요 없으며 외관의 변화가 거의 없고 저렴하다는 장점이 있다. 여러종류의 수동감쇠장치, 즉 TMD, IMD 그리고 TSD에 대한 개략적인 이론과 그 사용예에 대하여 설명하였다. 실험적 검증 및 실측결과 각 장치가 바람에 의해 야기되는 진동현상을 억제하는데 매우 유효한 것으로 판정되었고 또한 크기가 소규모일 뿐 아니라 유지보수가 거의 없으며 비용도 저렴하여 국내 건설 또는 건설예정인 유사구조물에도 많은 적용이 예상된다.

• The Magazine for Energy Service Companies
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• s.34
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• pp.26-27
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• 2005

30년 넘게 산업용 플랜트와 화공장치에서 전문적인 기술력을 과시해온 두산메카텍㈜이 기존의 사업에 에너지절약기술을 접목해 이 시장에서 강자 자리를 노리고 있다. 특히 이 회사는 폐열을 회수해 재사용하는 열병합발전설비를 중심으로 산업용 플랜트의 에너지절감사업에 적극적으로 나설 계획이다. 이 회사의 ESCO사업 담당자인 플랜트 영업팀 서승원 과장을 만나 앞으로의 포부와 계획에 대해 들어봤다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.06a
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• pp.150-155
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• 2000

우리나라의 공업현대화는 1960년대 초의 경제개발계획으로부터 시작되었으며, 그 당시 우리의 현실은 인천제철과 충주비료공장을 제외하고는 장치 산업이라는 대형산업시설이 거의 없었다. 그 후 경제개발의 박차를 가하면서 울산공업단지와 항만$\cdot$배후 시설등의 건설에 힘입어 1970년 초부터 현대적 공업국으로 진입하게 되었다. (중략)

• The Science & Technology
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• v.28 no.8 s.315
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• pp.31-33
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• 1995

우리나라 최초로 설치되니 대형 플라스마 발생기가 「한빛」장치가 지난 6월21일 준공되었다. '제 4의 물질상태'라고 불리는 플라스마 발생기기「한빛」장치는 미국 MIT대학에서 3천만 달러를 들여 시설한 것을 영구임대 형식으로 무상 임대받아 한국에 이전, 시설한 것이다. 9월부터 본격 가동될 「한빛」의 운영계획을 준공하기까지 산파역을 맡았던 기초과학지원연구소장 최덕인 박사에게 들어보았다.

• Journal of Gifted/Talented Education
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• v.25 no.1
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• pp.77-93
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• 2015

The purpose of this study was to explore the problem solving strategy for Goldberg machine tasks of the gifted students in elementary science depending on the cognitive style(tendency to field-dependent and field independent). It was aimed to provide suggestions for the features and differences of the problem solving strategies of the gifted students in elementary science according to their cognitive styles. A total of 16 students, from the gifted class of P elementary school in Hwaseong were sampled for the research, cognitive styles Test was conducted to divide the students in teams, and the teams were classified according to cognitive style tendencies to five groups of field-dependent group, weak field-dependent group, mixed group, weak field-independent group and field-independent group. The Goldberg device task given was to make a Goldberg device within the angle framework of (Figure) 1, for a bead to start from the starting point and to reach the final point the last. The results are as follows: First, regarding the plan for producing the device, the stronger the field-independent tendency, they established more specific strategy-reflected plan; the stronger the field-dependent tendency, they established less specific strategy-reflected plan. Second, all cognitive style groups took a limited period of time into consideration, to fabricate the devices for the ball to arrive the last using a fine adjustment rather than many devices. Third, the field-independent group used a lot of logical reasoning; the field-dependent group used a lot of intuitive thinking. Fourth, the field independent group properly utilized strategies such as cooperation and role allocation; the field-dependent group tried to solve the task personally rather than cooperatively with poor role allocation. Fifth, the intermediate mixed group solved the problem better than the inclined groups such as field-dependent or field-independent groups.

• The Journal of Korean Society for Radiation Therapy
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• v.16 no.1
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• pp.57-65
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• 2004

Introduction : The phantom that includes high density materials such as steel was custom-made to fix lung and bone in order to evaluation inhomogeneity correction at the time of conducting radiation therapy to treat lung cancer. Using this, values resulting from the inhomogeneous correction algorithm are compared on the 2 and 3 dimensional radiation therapy planning systems. Moreover, change in dose calculation was evaluated according to inhomogeneous by comparing with the actual measurement. Materials and Methods : As for the image acquisition, inhomogeneous correction phantom(Pig's vertebra, steel(8.21g/cm3), cork(0.23 g/cm3)) that was custom-made and the CT(Volume zoom, Siemens, Germany) were used. As for the radiation therapy planning system, Marks Plan(2D) and XiO(CMS, USA, 3D) were used. To compare with the measurement value, linear accelerator(CL/1800, Varian, USA) and ion chamber were used. Image, obtained from the CT was used to obtain point dose and dose distribution from the region of interest (ROI) while on the radiation therapy planning device. After measurement was conducted under the same conditions, value on the treatment planning device and measured value were subjected to comparison and analysis. And difference between the resulting for the evaluation on the use (or non-use) of inhomogeneity correction algorithm, and diverse inhomogeneity correction algorithm that is included in the radiation therapy planning device was compared as well. Results : As result of comparing the results of measurement value on the region of interest within the inhomogeneity correction phantom and the value that resulted from the homogeneous and inhomogeneous correction, gained from the therapy planning device, margin of error of the measurement value and inhomogeneous correction value at the location 1 of the lung showed $0.8\%$ on 2D and $0.5\%$ on 3D. Margin of error of the measurement value and inhomogeneous correction value at the location 1 of the steel showed $12\%$ on 2D and $5\%$ on 3D, however, it is possible to see that the value that is not correction and the margin of error of the measurement value stand at $16\%$ and $14\%$, respectively. Moreover, values of the 3D showed lower margin of error compared to 2D. Conclusion : Revision according to the density of tissue must be executed during radiation therapy planning. To ensure a more accurate planning, use of 3D planning system is recommended more so than the 2D Planning system to ensure a more accurate revision on the therapy plan. Moreover, 3D Planning system needs to select and use the most accurate and appropriate inhomogeneous correction algorithm through actual measurement. In addition, comparison and analysis through TLD or film dosimetry are needed.

• Bulletin of the Korean Space Science Society
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• 1993.04a
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• pp.23-25
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• 1993

밀리미터파 영역에서의 관측장치를 살펴보면, 단일망원경을 제외하고도 세계의 밀리미터파 간섭계의 그 어느 것이나 현재 확장작업을 진행중이며, 또 밀리미터파서브밀리미터파영역에서의 고분해능 관측의 천문학적 성과를 올리기 위해 서브밀리미터파 간섭계의 건설계획을 추진하고 있고, NARO에서도 NMA계획을 발표하여 그 준비가 착착 진행되고 있다. 이들에 대해, 일본의 NRO에서도 HMA확충계획을 진행시키는 한편, 대형밀리미더파 간섭계(LMA) 계획을 발표하고 있다. 따라서 일본 내부에서는 SUBARU 망원경건설 이후의 천문학 분야에서의 차기 대형 장래계획으로서 LMA가 자리잡고 있다. 따라서 본 발표에서는, 세계의 이러한 추세 속에서 향후 5년 내지는 10년 이후를 내다보고 우리나라 전파천문학은 앞으로 무엇을 해 나가야 할 것인가, 그리고 무엇이 우리의 실정에 가장 적합한 천문학인지를 생각해 보기 위한 한 방편으로, 측지적인 목적과 전파천문학적인 견지에서의 국내 및 국외 VLBI Network 형성과 LMA 계획을 분석해보고자 한다.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.11a
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• pp.199-204
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• 2002

Reliability Centered Maintenance(RCM) was initially developed for the commercial aviation industry in the late 1960s and now is equally applicable to a variety of equipment other than aircraft. RCM is a method for establishing a preventive maintenance program which will efficiently and effectively allow the achivement of the required safety and availability levels of equipment and structures. RCM provides for the use of a decision logic tree to identify applicable and effective preventive maintenance requirements for equipment and structures. The end result of working through the decision logic is a judgement as to the necessity of performing a maintenance task. In this paper, we provide guiding principles based on IEC 60300-3-11 for RCM analysis methods and operational method of structure and equipment.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.11a
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• pp.199-204
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• 2002

Reliability Centered Maintenance(RCM) was initially developed for the commercial aviation industry in the late 1960s and now is equally applicable to a variety of equipment other than aircraft. RCM is a method for establishing a preventive maintenance program which will efficiently and effectively allow the achivement of the required safety and availability levels of equipment and structures. RCM provides for the use of a decision logic tree to identify applicable and effective preventive maintenance requirements for equipment and structures. The end result of working through the decision logic is a judgement as to the necessity of performing a maintenance task. In this paper, we provide guiding principles based on IEC 60300-3-11 for RCM analysis methods and operational method of structure and equipment.