노발리스를 이용한 방사선 수술시 치료테이블을 투과하는 광자선의 감쇠율에 따른 선량 보정방법

김성준,신현수,고승영,박혜리,김자영,이보미,예지원,김성규,Kim, Sung-Joon,Shin, Hyun-Soo,Ko, Seung-Young,Park, Hye-Li,Kim, Ja-Young,Lee, Bo-Mi,Yea, Ji-Woon,Kim, Sung-Kyu 한국의학물리학회 2011 의학물리 Vol.22 No.1

본 연구는 노발리스용 치료테이블(couch top)을 투과하는 광자선의 감쇠율(attenuation rate)을 기하학적 모델을 통해 계산하고 보정함으로써, 치료부위에 정확한 선량이 전달되게 하는데 그 목적이 있다. 실험은 치료테이블을 투과하는 광자선의 투과율과 감쇠율을 기하학적인 모델에 의해 예측하고 이를 바탕으로 실험적으로 측정된 것을 비교 및 분석하였다. 그 결과 기하학적 모델에 의해 예측된 값과 실험값이 매우 잘 일치하는 것으로 나타났다. 또 실제 임상적용의 가능여부를 판단하기 위하여, 척추 방사선수술(spine radiosurgery)환자의 치료계획에 모델링화한 감쇠율을 보정한 뒤 측정한 중심점 선량과 그렇지 않은 것을 비교하였더니, 전자가 치료계획된 것과의 오차율이 감소함을 보였다. 본 논문에서는 치료테이블을 투과하는 광자선의 기하학적 모델을 통해 투과율과 감쇠율을 계산하고 이를 실험적으로 증명하였다. 이 방법은 노발리스를 이용한 방사선 수술뿐만 아니라 일반적인 방사선 치료에 있어서도 매우 유용할 것으로 판단된다. This study has its own goal to deliver the accurate dose on the target volume by calculating and modifying the attenuation rate of photon beam transmitting the couch top with geometric model. The experiment was that the transmission rate and attenuation rate of photon beam transmitting the couch top was predicted by the geometric model, then compared and analyzed with what was measured experimentally based on that. The result showed that the predicted value by the geometric model accorded closely with the experimental value. In addition, in order to judge whether the practical clinical application is available, the point dose, measured after modifying the attenuation rate modelinged according to the treatment plan of a patient of spine radiosurgery, was compared with the one done nothing. The result was that the former showed decreased error range with treatment planned one than the latter. This papers calculated the transmission and attenuation rate with the geometric model transmitting the couch top and verified it experimentally. This method is expected to be very useful in not only the radiosurgery using Novalis but also the general radiation therapy.

고고도 장기체공 무인기 구조 설계 및 해석

김성준,이승규,김성찬,김태욱,김승호,Kim, Sung Joon,Lee, Seunggyu,Kim, Sung Chan,Kim, Tae-Uk,Kim, Seungho 한국항공운항학회 2014 한국항공운항학회지 Vol.22 No.3

Research is being carried out at Korea Aerospace Research Institute with aim of design a HALE UAV(High Altitude Long Endurance Unmanned Air Vehicle). HALE UAVs are ideally suited to provide surveillance, remote sensing and communication relay capabilities for both military and civilian applications. HALE UAVs typically cruise at an altitude between 15 km and 20 km, travelling at low speed and circling specific area of interest. Airframe structural point of view, weight reduction of the airframe structure is the most important method to improve the flight efficiency. High modulus CFRP(Carbon Fiber Reinforced Polymer) has been used in designing the structure in order to minimize the airframe weight. With respect to structural design and analysis, the key question is to decide an adequate airworthiness certification base to define suitable load cases for sizing of various structural components. In this study, FAR(Federal Aviation Regulation) 23 have constituted the guidance and benchmark throughout all structural studies. And the MSC/FlightLoads was introduced to analyze the flight loads for the HALE UAV. The MSC/FlightLoads can compute the flexible air load and analyzed loads are distributed on structural model directly. A preliminary structural concept was defined in accordance with the estimated inertial and aerodynamic loads. A FEM analysis was carried out using the MSC/Nastran code to predict the static and dynamic behaviour of UAV structure.

소형 무인기 구조 안전계수

김성준,이승규,김태욱,Kim, Sung-Joon,Lee, Seung-gyu,Kim, Tae-Uk 한국항공운항학회 2017 한국항공운항학회지 Vol.25 No.2

Manned aircraft structural design is based on structural safety factor of 1.5, and this safety factor is equivalent to a probability of failure of between 10-2 and 10-3. The target failure probability of FARs is between 10-6 and 10-9 per flight according to aircraft type. NATO released STANAG 4703 to established the airworthiness requirements for small UAV which is less than 150kg. STANAG 4703 requires the Target Level of Safety according to MTOW. The requirements of failure probability for small UAV is between 10-4 and 10-5. In this paper, requirements of airworthiness certification for small UAV were investigated and the relationship of safety factors to the probability of structural failure is analyzed to reduce measure of safety factor and structural weight of unmanned aircraft.

초등수학영재를 위한 교수학습 자료 개발 및 적용

김성준,Kim, Sung Joon 영남수학회 2021 East Asian mathematical journal Vol.37 No.4

This study analyzes the characteristics of elementary math gifted classes through the development and application of teaching and learning materials. We used the guided reinvention methods including quasi-experiential perspectives. To this end, the applicability of Lakatos' quasi-empirical mathematical philosophy in elementary mathematics was examined, and the criteria for the development of teaching and learning materials for gifted students were presented, and then this study was conducted in this theoretical background. The subjects of the study were 21 elementary students at P University's Institute of Science and Gifted Education, and non-face-to-face real-time classes were conducted. Classes were divided into introduction, deployment1, deployment2, organization stages, and in each stage, small group cooperative learning was conducted based on group activities, and in this process, the characteristics of elementary mathematics gifted were analyzed. As a result of the study, elementary mathematics gifted students did not clearly present the essence of justification in the addition algorithm of fractions, but presented various interpretations of 'wrong' mathematics. They also showed their ingenuity in the process of spontaneously developing 'wrong' mathematics. On the other hand, by taking interest in new mathematics starting from 'wrong' mathematics, negative perceptions about it could be improved positively. It is expected that the development of teaching and learning materials dealing with various and original topics for the gifted students in elementary school will proceed through follow-up research.

항공기 피로수명 입증방법 연구

김성준,김태욱,Kim, Sung Joon,Kim, Tae-Uk 한국항공운항학회 2016 한국항공운항학회지 Vol.24 No.1

This paper reviews and summarizes overall fatigue substantiation method of aircraft. The fatigue substantiation method has been studied using the related regulation and examples of industry application. And the comparisons of fatigue substantiation procedure between safe-life and damage tolerance design have been performed. Fatigue substantiation methods have wide variability depend on design methodology and type of aircraft such as fixed wing and rotorcraft. In this study, fatigue substantiation methodologies have been reviewed using analysis and test methods.

유무인 겸용 개인항공기(OPPAV) 개념설계를 위한 구조물 사이징

김성준,이승규,Kim, Sung Joon,Lee, Seung-gyu 한국항공운항학회 2020 한국항공운항학회지 Vol.28 No.1

Personal air vehicle (PAV) is considered by aviation engineers as a solution to provide fast urban mobility. The purpose of designing a optionally piloted PAV (OPPAV) is to provide an individual air vehicle. The airframe structure is designed with high strength carbon fiber composite to reduce the aircraft weight. This paper presents an overview of sizing process for OPPAV at the conceptual design level. It consists of load analysis, structural sizing and development of efficient design allowable values for composite material. The weight is estimated based on sizing process, including strength and stiffness requirements. The objective of this study is to present a overview of structural sizing procedure and fast tool for preliminary design phases.

라이프니츠의 분석법에 관한 고찰

김성준,Kim, Sung-Joon 한국수학사학회 2006 Journal for history of mathematics Vol.19 No.4

This paper aims to review Leibniz's analytic ideas in his philosophy, logics, and mathematics. History of analysis in mathematics ascend its origin to Greek period. Analysis was used to prove geometrical theorems since Pythagoras. Pappus took foundation in analysis more systematically. Descartes tried to find the value of analysis as a heuristics and found analytic geometry. And Descartes and Leibniz thought that analysis was played most important role in investigating studies and inventing new truths including mathematics. Among these discussions about analysis, this paper investigate Leibniz's analysis focusing to his ideas over the whole of his studies. 수학에서 분석(analysis)의 역사는 고대 그리스에서부터 시작되었다. 그리스의 기하적 분석법은 16세기 비에트$(Vi{\`{e}}te)$와 데카르트(Descartes) 이후 방정식을 이용한 문제해결(대수적 분석법)로 확장되었으며, 그 결과 대수는 분석을 위한 기술(art for analysis)로 대변되었다. 그리고 뉴헌(Newton)과 라이프니츠(Leibniz)에 의해 미적 분학이 탄생되면서 분석은 대수에서 한 걸음 더 나아가 오늘날 수학의 한 분야인 해석학으로 발전되었다. 그 동안 수학교육학 연구에서는 분석과 관련된 논의가 파푸스(Pappus)와 데카르트를 중심으로 다루어져 왔으나, 지금까지 라이프니츠의 역할과 그에 대한 연구는 거의 다루어지지 않았다. 본 연구는 라이프니츠의 철학 및 논리학을 바탕으로 그 가운데 분석과 관련된 그의 아이디어를 살펴보고, 이를 통해 그가 생각한 수학에서의 분석의 역할에 대해 논의하였다.

2차원 배열형 이온함의 부피효과가 세기조절방사선치료의 선량분포 측정에 미치는 영향

김성준,이승준,박인규,이정은,박신형,설기호,김재철,Kim, Sung Joon,Lee, Seoung Jun,Park, In Kyu,Lee, Jeong Eun,Park, Shin Hyung,Seol, Ki Ho,Kim, Jae Chul 한국의학물리학회 2013 의학물리 Vol.24 No.1

부피효과를 가지는 2차원 배열형 이온함으로부터 측정된 세기조절방사선치료의 선량분포와 부피효과를 가지지 않는 장치로부터 측정된 선량분포를 비교함으로써 이 효과가 측정결과에 미치는 영향에 대해 평가하였다. 조사면 크기에 따라 총 5개의 세기조절방사선치료계획을 5문 조사방식으로 가상의 팬톰에 시행하였다. 선량분포 측정은 매트릭스 팬톰, 빔 영상시스템, 필름 등 총 3가지 측정장치를 이용하였다. 측정된 값은 분석프로그램을 이용하여 전산화치료계획 시스템을 통해 획득된 선량분포와 비교하였다. 비교된 선량분포는 분석프로그램 상에서 상관계수와 감마값을 통해 측정장치의 부피효과 유무에 따른 차이를 분석한 결과 매트릭스 팬톰에서 최대 1.3% 이상으로 나타났다. 매트릭스 팬톰은 조사면의 크기가 작아질수록 내부의 이온함에 의해 부피효과가 커지게 되므로 다른 측정장치에 비해 더 큰 측정오차를 가지는 것으로 판단되었다. We evaluated the influence of volume effect on the measurement of IMRT dose distribution by comparing a 2D-array ion chamber and other dosimeters. Matrix phantom which is a 2D-array ion chamber having volume effect was compared with beam image system and film for the measurement of dose distribution. Five intensity-modulated radiation therapy plans were created using five fields in thevirtual phantom. The measured dose distribution was compared with the calculated one by radiation treatment planning system and analysis program. We evaluated the conformity of dose distribution by calculating correlation coefficients and gamma values. The highest error rate of 1.3% was associated with matrix phantom in which volume effect in small field sizes was substantial.

파아지 T7전사종결제에 의한 파아지 SP6 와 T7 RNA 중합효소의전사종결반응

김성준,강창원 ( Sung Joon Kim,Chan Gwon Kang ) 생화학분자생물학회 1988 BMB Reports Vol.21 No.4

Transcription termination efficiencies of a phage T7 terminator Tø for the T7 and SP6 RNA polymerases were studied. The terminator Tø cloned in the plasmid pET-3 was subcloned into the plasmid pGEM3Z which contains both SP6 and T7 RNA polymerase promoters facing each other. Amounts of transcripts terminated at Tø were compared with amounts of read-through transcripts run off at a restriction site. For quantitative analysis the transcripts were labeled with [α-^(32)P]rNTP in in vitro transcription reaction. Transcription of T7 RNA polymerase terminates with efficiency of 78% by the Tø in the pET-3, but terminates with efficiency of 38% by the Tø in the pGEM3Z. It suggests that DNA sequences other than the terminator sequence affect the termination efficiency. Interestingly, the Tø shows 81% termination efficiency for the SP6 RNA polymerase. Now this becomes the first strong terminator discovered for the SP6 RNA polymerase. This also suggests that both phage RNA polymerases might share similar mechanism of transcription termination.

초등수학에서의 곱셈구구 지도 순서에 대한 고찰

김성준,Kim, Sung Joon 영남수학회 2016 East Asian mathematical journal Vol.32 No.4

The purpose of ths study is to compare and analyze the sequence of teaching multiplication facts in the elementary school mathematics. Generally, the multiplication in the elementary school mathematics is composed of the followings; concepts of multiplication, situations involving multiplication, didactical models for multiplication, and multiplication strategies for teaching multiplication facts. This study is focusing to multiplication facts, especially to the sequence of teaching and multiplication strategies. The method of this study is a comparative and analytic method. In order to compare textbooks, we select the Korean elementary mathematics textbooks(1st curriculum~2009 revised curriculum) and the 9 foreign elementary mathematics textbooks(Japan, China, Germany, Finland, Hongkong etc.). As results of comparative investigation, the sequence of teaching multiplication facts is reconsidered on a basis of elementary students' mathematical thinking. And the connectivity of multiplication facts is strengthened in comparison with the foreign elementary mathematics textbooks. Finally multiplication strategies for teaching multiplication facts are discussed for more understanding and reasoning the principles of multiplication facts in the elementary school mathematics.