Evaluation of Superficial Dosimetry in Postmastectomy Radiotherapy using High-energy Electromagnetic Radiation Treatment

Yong-Min Song,Byung-Suk Park,Byung-Ki Choi,Soo-Il Kwon,Jun-Chul Chun,Jeong-Min Seo 한국자기학회 2017 Journal of Magnetics Vol.22 No.4

The present study evaluated surface and superficial doses delivered by high-energy electromagnetic radiation treatment in patients who received postmastectomy radiotherapy. Computed tomography was performed using an RW3 slab phantom, and hypothetical target volumes were delineated. 6MV electromagnetic radiation beams were generated with five treatment plans: 2-field 3-dimentional conformal radiation therapy, 4-field intensitymodulated radiation therapy, 7-field intensity-modulated radiation therapy, TomoHelical 3-dimentional conformal radiation therapy, and TomoHelical intensity-modulated radiation therapy. Film dosimetry was performed with Gafchromic EBT3 film for dose measurement of high-energy electromagnetic radiation. The dose profile at the surface and superficial regions (1-6 mm depth) of the phantom obtained for each treatment technique. Compared to other techniques, Tomo 3-dimentional conformal radiation therapy had the highest surface dose (47-71 %). The superficial doses of TomoHelical 3-dimentional conformal radiation therapy and TomoHelical intensity-modulated radiation therapy were > 75 %, 80 %, and 90 % of the prescribed dose at 1, 2, and 5 mm depths, respectively. For postmastectomy radiotherapy, TomoHelical 3-dimentional conformal radiation therapy and TomoHelical intensity-modulated radiation therapy had higher surface and superficial doses than linear accelerator-based treatment techniques, with a sufficient dose of ≥ 75 % being delivered to the skin region at depths of 1 mm.

Electromagnetic Radiation Knowledge, Risk Awareness, and Shielding Practices of South Korean Occupational Therapists During Videofluoroscopic Swallowing Study: A Survey study

Na-Kyoung Hwang,Ji-Su Park,Man Seok Han,Jong-Bae Choi,Young-Jin Jung 한국자기학회 2022 Journal of Magnetics Vol.27 No.4

The videofluoroscopic swallowing study (VFSS) based on electromagnetic radiation is an instrumental test for diagnosing and rehabilitating dysphagia that is performed by many occupational therapists (OTs) in South Korea. This study aimed to investigate current electromagnetic radiation knowledge, risk awareness, and shielding practices of OTs performing VFSS and to identify educational experience on radiation protection. An online survey was conducted from April 2019 to June 2022, and a total of 69 responses were used for analysis. The mean correct score of ‘Radiation Knowledge’ was 3.24 ± 1.98 (out of 10). Mean scores of ‘Risk Awareness’ and ‘Shielding Practice’ were 2.18 ± 0.53 and 3.02 ± 0.74 (out of 5), respectively. Multiple regression analyses revealed that radiation knowledge (β = 0.292, p = 0.012) and risk awareness (β = 0.495, p < 0.001) were significant factors associated with shielding practices. Ninety-five percent of respondents had no radiation-related educational experience, and 83% reported that the reason for not participating was due to a lack of educational opportunities.

Personal Safety in Electromagnetic Environment of Electric Vehicle

Cheng Qiang,Du Zhong-min 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.6

With the extensive application of automotive electrical and electronic equipment, issues of electromagnetic radiation and electromagnetic compatibility have become increasingly prominent, human body in complex automotive electromagnetic environment is bound to be some damage of electromagnetic radiation. This paper established a relatively sophisticated car simulation model,through electromagnetic characteristics of antenna model, we got automotive electric field distribution and simulation results of human body SAR value, so conclusion can be drawn that automotive electromagnetic environment is relatively safe to passengers.

감마선 에너지에 따른 납치마의 차폐효과 분석

장동근(Dong-Gun Jang),이상호(Sang-Ho Lee),최형석(Hyung-Seok Choi),손주철(Joo-Chul Son),윤창용(Chang-Yong Yoon),지영식(Yung-Sik Ji),조용인(Yong-In Cho),이홍제(Hong je Lee),양승오(Seoung-Oh Yang) 대한방사선과학회(구 대한방사선기술학회) 2014 방사선기술과학 Vol.37 No.4

의료기관에서 사용되고 있는 전자파 방사선은 매우 다양한 에너지를 사용하고 있으며 연구자에 따라 고에너지의 전자파 방사선이 납치마와 상호작용을 한 후 차폐효과를 얻을 수 있다는 의견과 차폐가 효과가 없을 뿐만 아니라 오히려 피폭을 가중 시킨다는 상반된 의견이 제시되고 있다. 이에 본 연구에서는 몬테칼로 모사를 이용하여 전자파 방사선의 에너지에 따른 납치마의 차폐효과를 분석하고자 하였다. 몬테칼로 모사를 이용하여 전자파 방사선을 10 keV부터 500 keV까지 10 keV 단위로 1 MBq 방출시켜 납 차폐체의 유무에 따른 선량차이를 차폐율로 표현한 결과 납차폐체(0.25 mmPb)를 사용하여 차폐를 실시하였을 때 고에너지 전자파 방사선에서 차폐율이 현저히 떨어져 차폐시 오히려 선량이 증가됨을 알 수 있었다. The medical institution has been used electromagnetic radiation of various energy. But researchers are divided on whether using apron for radiation shielding will be effective or not. The purpose of present study was to analyze electromagnetic radiation shielding effect of apron by us-ing Monte carlo simulation. 1 MBq electromagnetic radiation was emitted from 10-500 keV at 10 keV increments in Monte carlo simulation. Then shielded radiation dose difference was confirmed, when 0.25 mmPb shield use for shielding. As a results, shielding ratio was markedly decreased in high energy electromagnetic radiation. The radia-tion dose was inversely increased with 0.25 mmPb shielding.

전자기 복사와 물질 사이의 상호작용 관련 현상에 대한 학생의 모형

김태은,정용욱,송진웅 한국물리학회 2016 새물리 Vol.66 No.9

This study investigated the models used by science high-school students to explain phenomena concerning the interactions between electromagnetic radiation and matter. The participants were 44 students at a science high school in Korea, who had learned ``Physics I'' during the previous semester and who were then studying introductory-level physics. They were asked to explain three phenomena ($i.e.$, `visible light not being able to penetrate a paper box' and `microwaves not being able to penetrate a paper box', `visible light being able to penetrate a glass box.') that are frequently encountered in everyday life. Students' responses were classified into 4 types: `did not use a model', `used a microscopic model', `used a macroscopic model', and `used a simple energy model'. Eleven types of specific models (6 microscopic models and 5 macroscopic models) were identified. Students used many already known concepts, such as `collisions', `vibrations', `refraction', `diffraction', `blackbody radiation', and `energy levels', to make a model, and their responses showed a context dependence for the phenomenon. 본 연구에서는 전자기 복사와 물질 사이의 상호작용과 관련된 현상에 대하여 과학고 학생들이 사용한 모형의 특징을 조사하였다. 연구 참여자는 서울시내 1개 과학고에 재학 중인 2학년 학생 44명으로 이들은 물리I 교과 학습을 마쳤고, 일반물리학 수준의 심화물리를 학습하는 중이었다. 이들에게 일상생활에서 쉽게 접하는 3가지 현상(가시광선이 종이상자를 투과하지 못하는 현상, 마이크로파가 종이상자를 투과하는 현상, 가시광선이 유리상자를 투과하는 현상)에서 일어난 전자기 복사와 물질 사이의 상호작용을 설명하도록 요구하는 서술형 문항을 제시하였다. 학생들의 응답은 4가지 유형 즉, `모형을 사용하지 않은 유형', `미시적 모형을 사용한 유형', `거시적 모형을 사용한 유형', `단순 에너지 모형을 사용한 유형'으로 분류되었으며, 구체적으로 총 11가지 세부 모형(미시적 모형 6가지, 거시적 모형 5가지)을 확인할 수 있었다. 학생들은 `충돌', `진동', `굴절', `회절', `흑체복사', `에너지 준위', `컴프턴 산란' 등 기존에 학습했던 다양한 개념을 사용하여 모형을 구성하였으며, 현상에 따라 다른 설명유형을 사용하는 상황의존적인 특성을 보였다.

고등학교 물리교과를 통한 방사선 이해 교육의 필요성

최경호,조정근 사단법인 미래융합기술연구학회 2022 아시아태평양융합연구교류논문지 Vol.8 No.9

The necessity of radiation education in schools has been constantly addressed in Korea since the research and development of the relevant curriculum in 2015. Accordingly, there are well-developed teaching/learning materials which aim to educate rational behaviors and decisions on nuclear power and radiation. However, high schools rarely give education on radiation and related safety for many reasons. The term radiation is hard to find even in Physics textbooks that high school students learn content related to radiation. Therefore, this research suggests the necessity of including appropriate education on radiation in high school’s Physics curriculum, to teach positive aspects of radiation as well as to protect our body. Physics questions in the College Scholastic Ability Test for the last 10 years have been analyzed, and appropriate suggestions are proposed to help improve the curriculum of high school physics education. 우리나라의 경우 2015년 이후 방사선 교육과정 개발연구와 함께 학교교육 도입의 필요성이 꾸준하게 제기되고 있는 실정이다. 이에 따라 원자력과 방사선에 대한 합리적인 판단과 행동을 할 수 있는 인간 추구를 목표로 하는 교수-학습 자료도 개발되어 있다. 그러나 고등학교의 경우 여러 가지 이유로 인하여 방사선 및 방사선으로부터의 안전과 관련된 학교교육은 거의 이루어지고 있지 않다. 심지어 방사선과 관련된 학습내용이 있는 고등학교 물리 교과서에서조차도 방사선이라는 용어는 보이지 않고 있다. 본 연구에서는 방사선이 갖는 긍정적인 측면도 많을뿐더러 우리 몸을 보호하기 위해서라도, 고등학교 물리 교육과정에서 방사선에 대한 정확한 이해를 위한 교육의 필요성을 제기하였다. 이를 위해 지난 10개년 동안의 대학수학능력 시험 물리 문항을 분석해 보고, 향후 고등학교 물리 교과서 개편에 도움을 줄 수 있는 제언을 하였다.

Radioprotective Effect of HME-Mulberry Leaves against Electromagnetic Radiation-Induced Damage in Rats

Cheol-Ha Baek,Su-Ji Ryu,Hye-Min Kim,Seoul-Hee Nam,Jong-Suep Baek,Byung-In Min,Jang-Oh Kim 한국자기학회 2023 Journal of Magnetics Vol.28 No.4

In this study, a solid dispersion containing mulberry leaves and additives was manufactured by hot-melt extrusion (HME) to develop a radioprotective agent against electromagnetic radiation. The prepared formulations were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and electrophoretic light scattering (ELS). The formation of regular dispersions was confirmed through SEM and TEM analysis. To explore the radioprotective effect, animals were randomly classified into four groups: normal control (NC), irradiation (IR), irradiation after administration with mulberry leaves (MR), and irradiation after administration with HME-mulberry leaves (HR). Each sample was orally administered at 100 ㎎/㎏/day, and 7 Gy of 6 MV electromagnetic radiation (X-ray) was used once for the whole body. Lymphocytes seemed to recover in the HR group, but none of the groups recovered at a normal range by the seventh day after irradiation. There was also no change in all groups of the red blood cells. The spleen index tended to recover in the HR group compared to the IR group, which was consistent with histological analysis. The spleen of the radiation-exposed groups (IR, MR, and HR) showed relatively atrophied white pulp and decreased lymphocytes. These symptoms further increased on the third day after irradiation and gradually alleviated on the seventh day. Compared to the IR group, the MR and HR groups had less loss of lymphocytes caused by damage to the white pulp. Specifically, the HR group demonstrated a higher recovery rate than the MR group, confirming the potential of HME-Mulberry as a radioprotective agent. The study’s findings suggest further studies on health supplements and medicines to supplement the current research.

Prediction of Magnetic Pollution with Artificial Neural Network in Living Areas

Sakacı Furkan Hasan,Cerezci Osman 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.5

The high voltage transmission and distribution lines are source of the extremely low frequencies (ELF) radiation. The increasing use of transmission of electrical energy is causing concerns regarding the risks of human exposure to ELF from the lines. In recent years studies investigating the interaction of ELF magnetic fi elds with human body have become important. Epidemiological studies report that magnetic fi elds emitted from power lines increase the incidence of leukemia in the children of people living near power lines. In the municipality of Nilufer with a population of 600,000 in Bursa province, which is one of the largest cities in Turkey, high voltage lines pass over residential areas or very close to houses and schools. Studies are being carried out to reduce electromagnetic pollution in this region. Within the scope of this study, magnetic fi eld measurement values arising from high voltage lines were taken between 2014 and 2019. In order to make sense of these values, fi rst of all analyzes were made by mapping. After the analysis, the data set was created by labeling. Using the data set created, magnetic measurement values were trained based on parameters in dataset. After the training, the predictions and actual results were compared by testing with the data not used during the training. In addition, by making 3D drawings according to the latitude and longitude of the region, places where electromagnetic pollution may be high were found and measures were taken for these places

함정 구조물에 의한 탐색 레이다 신호 왜곡 현상 분석 및 대책

송기환(Ki-Hwan Song) 한국전자파학회 2009 한국전자파학회논문지 Vol.20 No.7

본 논문에서는 함정에 탑재된 탐색 레이다의 신호 왜곡 현상에 대한 분석 및 대책에 대해 소개한다. ShipEDF 프로그램을 이용하여 탐색 레이다의 주 안테나와 함정 구조물을 전자기학적으로 모델링하고, 광선 추적 기법을 이용하여 탐색 레이다의 자유공간 및 함정 탑재 상태에서의 복사 패턴을 분석한다. 분석된 복사 패턴을 통해 탐색 레이다의 신호 왜곡 현상이 마스트의 전자파 반사로 인한 복사 패턴 왜곡에 의한 것임을 알 수 있었고, 이에 대한 대책 수립을 위해 탐색 레이다에 의한 마스트 표면 전류 분포를 분석한다. In this paper, we introduce the analysis and counter-measure of signal distortion of search radar equipped on the ship. Using ShipEDF program, the search radar's main antenna and ship structures are modeled in the view of electromagnetism. Ray tracing method is used for analysis of the search radar's radiation patterns in free space and ship condition. From analyzed radiation patterns, we can conclude that the search radar's signal distortion is due to radiation pattern distortion. We also analyze the surface current distribution of the mast to propose the counter-measure to reduce electro-magnetic field reflection of mast.

Analysis and Design of Switched Transmission Line Circuits for High-power Wide-band Radiation

류지헌,Dong Woo Yim,Jaimin Lee 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.61

High Power Wide-Band (HPWB) radiators have been studied for a number of applications such as electromagnetic car stopper. Switched Transmission Line Circuit (STLC) is widely used as Ultra Wide-Band (UWB) and Wide-Band (WB) pulse generator in HPWB radiator. Since performance of the STLC depends on methods to connect switch to transmission line, in a stage of conceptual design we qualitatively determine a method of connection with respect of increasing amplitude of radiated electric fields and energy efficiency. We present circuit analysis for the STLC built by this method. The results of analysis are useful for understanding and designing HPWB radiators using the STLC. A couple of HPWB radiators based on this approach are introduced as examples.