• Progress in Medical Physics
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• v.19 no.1
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• pp.9-13
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• 2008

The purpose of this study was to measure the skin dose using the glass dosimeter and diode and to compare those measurements to the planned skin dose from the treatment planning system. For the reproducibility of the glass dosimeter (ASAHI TECHNO GLASS CIRPORATION, Japan), the same dose was irradiated to 40 glass dosimeters three times, among which 28 with the reproducibility within 3% were selected for the use of this study. For each of 27 breast cancer patients, the glass dosimeters and diodes were attached to 4 different locations on the skin to measure the dose during treatment. All the patients received one fraction of 180 cGy each. The maximum difference of measurements between the glass dosimeter and diode at the same location was 3.2%. Comparing with the planned skin dose from the treatment planning system (Eclipse v6.5, Varian, USA), the dose measured by the glass dosimeter and the diodeshowed on an average 3.4% and 2.3% difference, respectively. The measured doses were always less than the planned skin dose. This may be due to the specific errors of both detectors. Also, the difference may be caused by the fact that since the skin where the detectors were attached is pretty moveable, it was not fix the detectors on the skin.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.4
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• pp.152-159
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• 2007

In this paper, a new design technique on the LRF which is useful for low power laser and a CBDA(Cummulative Binary Detection Algorithm) is proposed. The LD(Laser Diode) and Si-APD(Silicon Avalanche Photo Diode) are used for saving a power. In order to prove the detection range, the Si-APD binary data are accumulated before the range computation and the range finding algorithm. A prototype of the proposed DLRF(Diode Laser Range Finder) system was made and tested. An experimental result shows that the DLRF system have the same detection range using a less power(almost 1/32) than an usual military LRF. The proposed DLRF can be applied to the Unmanned Vehicles, Robot and Future Combat System of a tiny size and a low power LRF.

• Proceedings of the Optical Society of Korea Conference
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• 2003.02a
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• pp.48-49
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• 2003

저출력 다이오드 여기 레이저에서는 공간모드 특성을 좋게하고 여기 효율을 올리기 위하여 단면 여기 방식을 주로 사용한다. 특히 레이저 다이오드 (LD)로 여기하는 단일모드 녹색광 레이저는 홀로그램, 간섭계, 측정기 등의 응용분야에서 수요가 날로 증가하고 있다. 단일모드 녹색광 레이저의 발진방법으로는 여러 가지가 고안되어 왔다. 먼저 공진기 내부에 얇은 판을 브루스터 (Brewster) 각으로 두어서 편광시키고 이것을 복굴절특성을 가진 Nd：YVO$_4$ 결정과 결합시켜 복굴절 필터 기능을 하게 하는 방법이 있다. (중략)

• 대한방사선치료학회:학술대회논문집
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• 2003.03a
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• pp.7-8
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• 2003

• Radiation Oncology Journal
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• v.7 no.1
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• pp.93-100
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• 1989

Several combinations of measuring devices and phantoms were studied to measure electron beams. Silicon Pmt junction diode was used to find the dependence of depth dose profile on field size on axis of electron beam Depths of 50, 80 and $90\%$ doses increased with the field size for small fields. For some larger fields, they were nearly constant. The smallest of field sizes over which the parameters were constant was enlarged with increase of the energy of electron beams. Depth dose distributions on axis of electron beam of $10\times10cm^2$ field were studied with several combinations of measuring devices and phantoms. Cylindrical ion chamber could not be used for measurement of surface dose, and was not convenient for measurement of near surface region of 6MeV electron. With some exceptions, parameters agreed well with those studied by different devices and phantoms. Surface dose in some energies showed $4\%$ difference between maximum and minimum. For 18MeV, depths of 80 and $90\%$ doses were considerably shallower by film than by others. Parallel-plate ion chamber with polystyrene phamtom and silicon PN junction would be recommended for measurement of central axis depth dose of electron beams with considerably large field size. It is desirable not to use cylindrical ion chamber for the purpose of measurement of surface dose or near surface region for lower energy electron beam. It is questionable that film would be recommended for measurement of dose distribution of electron with high energy like as 18MeV.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.2 s.95
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• pp.74-81
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• 1999

The integrated chip of optical micro-encoder was fabricated and the feasibility as displacement measurement device was confirmed. The geometry of micro-encoder was designed to utilize the optical interference effect on the second order of diffracted beams. The hybrid-type micro-encoder consisted with light emitting diode, photodiode, polyimide wave-guide and micro-lens provides stable micro-encoding results for high speed displacements. The measurement shows the resolution of displacement of 1.00 +/- 0.02 ${\mu}m$ for the grating with scale pitch of 2.0${\mu}m$.

• Journal of radiological science and technology
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• v.25 no.2
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• pp.71-75
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• 2002

According to this study, we can make the radiation check meter which have not supply because of high cost and import barrier and lengthen its life by means of repairing of radiation bomb and equipment. We can make better medical service. In my study, I used the photodiod, photoelectron, among semiconductor detectors which have a excellent detect capacity and are low cost and small size. I set up this equipment in June 1, 2002, used 640 mA remote operative fluorography equipment, which make the grade as capacity test. I used the standard measuring instrument which took proofs from a agency, now it was using in measuring agency. The comparative measuring instrument used in same condition. I took the standard which was gauged with a connecting measuring instrument. Using a existing unconnected measuring instrument, I compared the accuracy with new unconnected one. As a result, three score are within the standard. For the detailed analysis, I took the average of percentage average error. So standard instrument was -0.02, comparable was -0.22, and new one was -0.17. New one took a closer measured value with standard than comparable one. In more study, I think to take more accurate value. I expect that my study will be a base of measuring instrument, with low cost, supply of this instrument increase, I expect to decrease radiation bomb and maintain, repair and manager better.

• Radiation Oncology Journal
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• v.21 no.4
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• pp.322-329
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• 2003

Purpose: It is difficult to exactly determine the surface dose and the dose distribution In buildup region of high energy X-rays by using the conventional ion chamber. The aim of this study Is to evaluate the accuracy of widely used dosimetry systems to measure the surface dose and the depth of maximum dose (d$_{max}$). Materials and Methods: We measured the percent depth dose (PDD) from the surface to the d$_{max}$ in either a water phantom or in a solid water phantom using TLD-100 chips, thimble type ion chamber, diode detector, diamond detector and Markus parallel plate ion chamber for 6 MV and 15 MV X-rays, 10$\times$10 cm$^{2}$, at SSD=100cm. We analysed the surface dose and the d$_{max}$. In order to verify the accuracy of the TLD data, we executed the Monte Carlo simulation for 5 MV X-ray beams. Results: The surface doses In 6 MV and IS MV X-rays were 29.31% and 23.36% ior Markus parallel plate ion chamber, 37.17$\%$ and 24.01$\%$ for TLD, 34.87$\%$ and 24.06$\%$ for diamond detector, 38.13$\%$ and 27.8$\%$ for diode detector, and 47.92$\%$ and 35.01$\%$ for thimble type ion chamber, respectively. in Monte Carlo simulation for 6 MV X-rays, the surface dose was 36.22$\%$, which Is similar to the 37.17$\%$ of the TLD measurement data. The d$_{max}$ In 6 WV and 15 MV X-rays was 14$\~$16 mm and 27$\~$29 mm, respectively. There was no significant difference in the d$_{max}$ among the detectors. Conclusion: There was a remarkable difference in the surface dose among the detectors. The Markus parallel plate chamber showed the most accurate result. The surface dose of the thimble ion chamber was 10$\%$ higher than that of other detectors. We suggest that the correction should be made when the surface dose of the thimble ion chamber Is used for the treatment planning ion the supeficial tumors. All the detectors used In our study showed no difference in the d$_{max}$.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.278-280
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• 2005

원자력발전소 내 원자로의 유지보수 작업을 수행하는 수중로봇은 고준위 방사선에 노출되고, 이로 인해 전자 장치의 오동작 및 고장이 유발될 수 있다. 따라서 허용 방사선량을 초과하지 않도록 피폭되는 누적 방사선량을 실시간으로 모니터링하는 장치가 필수적이다. 본 연구에서는 펄스형의 SiC 포토 다이오드와 선량 기억형인 MOSFET를 다중 방사선 센서로 사용하여 넘은 범위의 방사선 준위의 측정이 가능하고 측정 신뢰도가 향상된 고준위 방사선 측정기를 구현하였다. 이 장치는 측정 원리가 상이한 두 센서를 동일한 방사선 측정에 이용함으로써 방사선 측정의 안정성과 정확성이 향상된 것이 특징이다.

• Journal of The Korean Radiological Technologist Association
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• v.29 no.1
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• pp.6-11
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• 2003

목적 : 전신방사선조사(TBI)시 균등한 선량을 조사할 목적으로 사용되는 각 신체부위별 보상체(compensator) 두께의 결정은 열형광선량계(TLD)를 이용하여 표면선량(surface dose)을 측정하고, 심부선량(depth dose)으로 환산하는 방법을 주로 이용한다. 그러나 이와 같은 방법은 골(bone) 조직에 대한 선량감쇠(dose attenuation)의 영향이 고려되지 않아 신체중심부에서의 정확한 심부선량을 알 수가 없다. 이에 본 연구