• Progress in Medical Physics
• /
• v.10 no.2
• /
• pp.63-71
• /
• 1999

For the purpose of utilization in 3-D conformal radiotherapy and whole body radiosurgery, the Whole Body 3-Dimensional Topographic Radiation Therapy System has been developed. Whole body frame was constructed in order to be installed on the couch. Radiopaque catheters were engraved on it for the dedicated coordinate system and a MeV-Green immobilizer was used for the patient setup by the help of side panels and plastic rods. By designing and constructing the whole body frame in this way, geometrical limitation to the gantry rotation in 3-D conformal radiotherapy could be minimized and problem which radiation transmission may be altered in particular incident angles was solved. By analyzing CT images containing information of patient setup with respect to the whole body frame, localization and coordination of the target is performed so that patient setup error may be eliminated between simulation and treatment. For the verification of setup, the change of patient positioning is detected and adjusted in order to minimize the setup error by means of comparison of the body outlines using 3 CCTV cameras. To enhance efficiency of treatment procedure, this work can be done in real time by watching the change of patient setup through the monitor. The method of image subtraction in IDL (Interactive Data Language) was used to visualize the change of patient setup. Rotating X-ray system was constructed for detecting target movement due to internal organ motion. Landmark screws were implanted either on the bones around target or inside target, and variation of target location with respect to markers may be visualized in order to minimize internal setup error through the anterior and the lateral image information taken from rotating X-ray system. For CT simulation, simulation software was developed using IDL on GUI(Graphic User Interface) basis for PC and includes functions of graphic handling, editing and data acquisition of images of internal organs as well as target for the preparation of treatment planning.

• Radiation Oncology Journal
• /
• v.18 no.2
• /
• pp.107-113
• /
• 2000

Purpose : The goal of this study 닌as to improve the accuracy of three-dimensional conformal radiotherapy (3-D CRT) by measuring the treatment setup error and physiological movement of liver based on the analysis of images which were obtained by electronic portal imaging device (EPID). Materials and Methods : For 10 patients with hepatocellular carcinoma, 4-7 portal images were obtained by using EPID during the radiotherapy from each patient daiiy. We analyzed the setup error and physiological movement of liver based on the verification data. We also determined the safety margin of the tumor in 3-D CRT through the analysis of physiological movement. Results : The setup errors were measured as 3mm with standard deviation 1.70 mm in x direction and 3.7 mm with standard deviation 1.88 mm in y direction respectively. Hence, deviation were smaller than 5mm from the center of each axis. The measured range of liver movement due to the physiological motion was 8.63 mm on the average. Considering the motion of liver and setup error, the safety margin of tumor was at least 15 mm. Conclusion : EPID is a very useful device for the determination of the optimal margin of the tumor, and thus enhance the accuracy and stability of the 3-D CRT in patients with hepatocellular carcinoma.

• Radiation Oncology Journal
• /
• v.16 no.3
• /
• pp.265-274
• /
• 1998

Purpose : This prospective study has been conducted to assess the value of three dimensional conformal radiation therapy (3DCRT) for lung cancer and to determine its potential advantage over current treatment approaches. Specific aims of this study were to 1) find the most ideal 3DCRT technique 2) establish the maximum tolerance dose that can be delivered with 3DCRT and 3) identify patients at risk for development of radiation pneumonitis. Materials and Methods : Beginning in Nov. 1994, 95 patients with inoperable non-small cell lung cancer (stage I; 4, stage II; 1, stage IIIa; 14, stage IIIb; 76) were entered onto this 3D conformal trial Areas of known disease and elective nodal areas were initially treated to 45 Gy and then using 3DCRT technique 65 to 70 Gy of total dose were delivered to the gross disease. Sixty nine patients received 65 Gy of total dose and 26 received 70 Gy Seventy eight patients (82.1$\%$) also received concurrent MVP chemotherapy. 3DCRT plans were compared with 2D plans to assess the adequacy of dose delivery to target volume, dose volume histograms for normal tissue, and normal tissue complication Probabilities (NTCP). Results : Most of plans (78/95) were composed of non-coplanar multiple (4-8) fields. Coplanar segmented conformal therapy was used in 17 pateints, choosing the proper gantry angle which minimize normal lung exposure in each segment. 3DCRT gave the full dose to nearly 100$\%$ of the gross disease target volume in all patients. The mean NTCP for ipsilateral lung with 3DCRT (range; 0.17-0.43) was 68$\%$ of the mean NTCP with 2D treatment planning (range; 0.27-0.66). DVH analysis for heart showed that irradiated volume of heart could be significantly reduced by non-coplanar 3D approach especially in the case of left lower lobe lesion. Of 95 patients evaluable for response, 75 (79$\%$), showed major response including 25 (26$\%$) with complete responses and 50 (53$\%$) with partial responses. One and two rear overall survivals of stage III patients were 62.6$\%$ and 35.2$\%$ respectively. Twenty percent (19/95) of patients had pneumonitis; Eight patients had grade 1 pneumonitis and 11 other patients had grade 2. Comparison of the average of NTCP for lung showed a significant difference between patients with and without radiation pneumonitis. Average NTCP for Patients without complication was 62$\%$ of those with complications. Conclusions : This study showed that non-coplanar multiple fields (4-8) may be one of the ideal plans for 3DCRT for lung cancer. It also suggested that 3DCRT may provide superior delivery of high dose radiation with reduced risk to normal tissue and that NTCP can be used as a guideline for the dose escalation.

• Journal of Science of Art and Design
• /
• v.9
• /
• pp.117-136
• /
• 2006

The purpose of the present study is to explore the possibility of computer graphics as a new expression tool for high-grade elementary students' poster making by suggesting specific teaching-learning methods focused on expression using computer graphics to make posters in Unit 9 'Designing Notices' for 6th-grade elementary students. Through this study, we confirmed various possibilities of computer graphics as a new medium for art education and particularly its possibility for children's creative expression activities in expressing images hard to express with paper and brush and applying desired colors to the picture. The use of computer graphics as a new paradigm of art education in the 21st century is expected to contribute to the improvement of diversified visual literacy. Thus, art class in school education needs to take an active attitude in intrdoducing various multimedia.

• Korean Journal of Heritage: History & Science
• /
• v.57 no.2
• /
• pp.52-78
• /
• 2024

This study analyzes the sculptural art of SeokhaSichan(石霞施讚, 1893-1958), a significant figure in modern Korean Buddhist art, to re-examine his contributions and standing in the history of Korean Buddhist art. Sichan expanded the boundaries of modern Korean Buddhist art by developing a unique style based on the traditional sculptural techniques he learned from his mentor, Wanho Nakhyeon (玩虎洛現, 1869~1933). This study explores Sichan's artistic development, focusing on his artistic characteristics and sculptural evolution. Sichan's early works are characterized by small sculptures modeled after the main Buddha of Seokguram Grotto and heavily influenced by his mentor, WanhoNakhyeon. In his later works, notable features include a sense of massive volume, larger scale, upright postures, integration of the Buddha statue with its pedestal, and decorative treatment of drapery. These changes are interpreted as Sichan's response to social changes and his reflection of inner contemplation and artistic exploration in his works. This study reveals the influences of Wanho Nakhyeon, collaborations with Toewon Woneil(退雲圓日, 1877~1939), interactions with patron Kim Jiseonghwa(金至誠華), and master-disciple relationship with successor Geumchun Seongpil(金春性必) through literature review and newly discovered works by Sichan. His works and his artistic evolution are pivotal milestones in the history of modern Korean Buddhist sculpture, demonstrating a unique integration of traditional and modern aesthetics. This study provides valuable insights into how Sichan's artistic legacy was inherited and developed by subsequent generations and offers crucial materials for the study of modern Korean Buddhist sculpture history.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.792-795
• /
• 1996

In TIG welding of pipe, back bead size monitoring is important for weld quality assurance. Many researches have been performed on estimation of the back bead size by heat conduction analysis. However numerical conduction model based on many uncertain thermal parameters causes remarkable errors and thermomechanical phenomena in molten pool can not be considered. In this paper, filler wire feeding force in addition to weld current, wire feedrate, torch travel speed and orbital position angle is monitored to estimate back bead size in orbital TIG welding. Monitored welding process variables are fed into an artificial neural network estimator which has been trained with the monitored process variables (input patterns) and actual back bead size (output patterns). Experimental verification of the proposed estimation method was performed. The predicted results are in a good agreement with the actual back bead shape. The results are quite promising in that estimation of invisible back bead shape can be achieved by analyzing the welding parameters without any conventional NDT of welds.

• Archives of design research
• /
• v.13 no.2
• /
• pp.7-13
• /
• 2000

On the design or development of auto-vehicle, customer's images are strongly related to buying vehicles. I is importantly considered to review detailed specific properties of them. Product design includes functional quality, and aesthetics factors. among these, such as color sense, material of sense, and shape sense, the image of design feeling aesthetics has largely effect on the selling of products. From this point of view, it is not too much to say that the successful development of product is how design of it. The purpose of this study is to evaluate the sensibility of human needs, and apply it to the design of MEVs (Mini Electronic Vehicles).

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.6
• /
• pp.495-504
• /
• 2014

Solar sail spacecrafts can gain propulsion using the momentum change through reflecting the photon packets of energy from the Sun. The sail slowly but continuously accelerates to accomplish a wide-range of potential missions. To develop the potential mission of the solar sail, the configuration, the film characteristics and the deployment devices should be carefully considered. In this paper, recent development and activities of the solar sail are introduced and design technology of the sail subsystem is investigated.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.13 no.3
• /
• pp.11-17
• /
• 2017

The aerial support air sculptures currently exhibited in indoor spaces are similar to simple ad balloons, using multiple rope strands. Users now want more advanced unfixed sculptures, and hope these will develop into buoyant sculptures that can maintain the attitudes that users want on their own. This study investigated an attitude control system for unfixed levitation sculptures that can levitate with no rope and continuously maintain a certain attitude at a height specified by the user. To facilitate levitation, the exterior part of the sculpture was made of lightweight fibers, and the interior part was filled with helium gas. The controller was composed of a microprocessor of the dsPIC30F line from microchip, gyro, acceleration, and earth magnetic field sensors, and a highly efficient brushless DC (BLDC) electric motor. The attitude and position control system requires scheduling considering the trajectories of the sculpture and the control system, because the roles of the overall components are more important than those of a single controller. Furthermore, the system was designed like a fusion system that is expanded and controlled as a total controller, because it is interconnected with various sensors. The attitude control system of buoyant sculptures was implemented in this study, such that it can actively cope with the position, direction, stopping, and time aspects. The system performance was then evaluated.

• Proceedings of the KOR-BRONCHOESO Conference
• /
• 1987.05a
• /
• pp.22.1-22
• /
• 1987

인후부, 하인두부 및 경부 등에 종양감각(lump sensation)등의 이상감각을 호소하는 globus 증후군은 Hippocrates가 처음 기술한 이래 많은 저자들에 의해 여러 가지 다양한 원인들이 기술되어 왔지만 아직 뚜렷한 병인이 밝혀지지 않은 상태로 기질적 원인에 대한 다각적인 연구가 진행중이다. 이에 저자들은 1986년 7월부터 1987년 2월까지 연세대학교 의과대학 이비인후과학 교실을 방문한 85명의 globus 증후 환자를 대상으로 전향적 연구를 시행 다음과 같은 결과를 얻었다. 1) 주증상은 무언가 걸린듯한 느낌이 가장 많았고(40.8%), 기타 점액객출 및 종양감각이 있었으며, 증상부위는 하인두부(26.8%) 및 윤상연골부(28.0%)가 많았고. 증상 유발인자로는 피로 및 신경과민증이 동반된 기질적 병변으로는 비후성 설편도염 및 인두염이 가장 많았다. 2) 비데오-식도조영술 검사상 27명(31.8%)에서 윤상인두근 이상수축이 있었으며 기타 식도복(3명), 식도점막이상(1명)등이 있었고 윤상인두근 이상수축이 있었던 환자군과 없었던 환자군 사이에 주증상, 증상부위, 동반증상, 기질적 병변 및 치료경과에는 차이가 없었으며 50% 이상의 수축을 보인 3명의 환자에서 내시경 검사상 이상소견은 관찰되지 않았다. 3) 치료는 특별한 기질적 병변이 없는 한 자세한 설명을 통한 치유의 확신감을 주고 필요에 따라 진정제, 제산제 및 cimetidine을 투여한 결과 65.3%에서 증상의 완전소실 및 현저한 호전이 있었고, 24.5%에서는 어느 전도의 호전이 있었으며, 10.2%에서는 증상의 호전이 없었다.