• Title/Summary/Keyword: Concept of Radiation

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The Geometric Modeling for 3D Information of X-ray Inspection (3차원 정보 제공을 위한 X-선 검색장치의 기하학적 모델링)

  • Lee, Heung-Ho;Lee, Seung-Min
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.8
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    • pp.1151-1156
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    • 2013
  • In this study, to clearly establish the concept of a geometric modeling I apply for the concept of Pushbroom, limited to two-dimensional radiation Locator to provide a three-dimensional information purposes. Respect to the radiation scanner Pushbroom modeling techniques, geometric modeling method was presented introduced to extract three-dimensional information as long as the rotational component of the Gamma-Ray Linear Pushbroom Stereo System, introduced the two-dimensional and three-dimensional spatial information in the matching relation that can be induced. In addition, the pseudo-inverse matrix by using the conventional least-squares method, GCP(Ground Control Point) to demonstrate compliance by calculating the key parameters. Projection transformation matrix is calculated for obtaining three-dimensional information from two-dimensional information can be used as the primary relationship, and through the application of a radiation image matching technology will make it possible to extract three-dimensional information from two-dimensional X-ray imaging.

Preliminary Design Evaluation of Auxiliary Equipment for Transportation and Storage of Multi-purpose Canister (사용후핵연료 다목적 캐니스터의 운반 및 저장 보조 설비에 대한 예비설계 평가)

  • Chang Min Shin;Sang Hwan Lee;Yeon Oh Lee;In Su Jung;Gil Yong Cha
    • Journal of Radiation Industry
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    • v.17 no.3
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    • pp.309-320
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    • 2023
  • A multi-purpose canister (MPC) was developed for the purpose of transportation, storage and disposal of spent nuclear fuel (SNF) and has the advantage of minimizing repackaging between management stages of SNF. Considering the typical rock characteristics in Korea, a disposal canister is expected to contain 4 assemblies of Pressurized water reactor (PWR) SNF. The capacity of the MPC should be similarly designed with the disposal canister. However, the MPC with four SNF assemblies is expected to be less efficient in transporting and storing compared to a large-capacity canister. Therefore, a preliminary concept was derived for an auxiliary equipment that can transport and store multiple MPCs in a large overpack. A previously derived concept from US was thoroughly reviewed, and the preliminary concept was revised considering domestic situations including crane capacity and others. In addition, the safety of the normal transportation and storage of the MPC placed in transportation and storage overpack was evaluated with the auxiliary equipment.

Comparative Evaluation of Catchment-wide Solar Radiation to Locate Silver-town (실버타운 입지를 위한 집수구역별 일사량 비교평가)

  • Choi, Seon-Jeong;Um, Jung-Sup
    • Journal of the Korean Solar Energy Society
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    • v.34 no.5
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    • pp.11-22
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    • 2014
  • It is usual to determine silver-town location by people's experienced knowledge or intuition considering many different type of thematic variables simultaneously. This paper is primarily intended to locate sunny silver-town according to catchment-wide solar radiation as single key variable. GIS based solar simulation realistically identified catchment-wide solar radiation in the study area using large scale spatial precision. More than 90% over the worst catchment were identified shadow surfaces while the optimal catchment was heavily covered by sunny radiation surfaces. It is confirmed that standard GIS technology can offers the viable method of measuring and comparing the catchment-wide solar radiation. Guidelines for a replicable methodology are presented to provide a strong theoretical basis for the standardization of factors involved in locating the sunny silver-town; delineation of catchment boundary, solar simulation, catchment-wide comparison etc. They could be used as an evidence to determine sunny catchment in comparison with other catchment, based solar simulation. It is anticipated that this research output could be used as a valuable reference to confirm the potential of introducing the new concept of "catchment specific solar radiation" to support more scientific and objective decision-making in the process of locating silver town.

Introduction of Dental X-ray Imaging with New Concept - intra Oral x-ray Tube (신개념 치과용 X-선 영상장치 소개 - 강내형 X-선 튜브)

  • Cho, Sung-Ho;Kim, Dong-Young;Baek, Kwang-Woo;Lee, Re-Na
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.4
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    • pp.94-101
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    • 2011
  • Various kinds of medical imaging devices have been studied to develop periapical radiography. However, there are some problems such as high x-ray exposure rate and pains for patients because of the problems caused by intra-oral sensor based radiography system. In this study, a new concept of periapical radiography, intra oral X-ray tube and detector system, is introduced to solve these problems. This system is made up of miniature X-ray tube based on subminiature thermal electron or cold electron, CMOS based detector, and a body including automatic position and system control devices. In order to confirm the possibility of proposed new concept to periapical radiography, miniature x-ray tube from XOFT corporation is used to develop new x-ray system, and the performance evaluation of this system is performed according to collimator. Also, dental images are compared after acquiring both images from existing system versus new concept of system. As a result, new concept of system showed excellent image. Thus, it is considered that new concept of system will have a significant effect on medical imaging technology.

DEVELOPMENT OF A FRAMEWORK FOR ASSESSING RADIATION SOURCE TERMS IN NUCLEAR POWER PLANTS

  • Jae, Moo-Sung;Park, Shane;Kang, Kyung-Min;Jeun, Gyoo-Dong
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.197-201
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    • 2001
  • A risk analysis consists of a triplet, , where Si is the scenario identification; Pi is the probability of each scenario; and Xi is the consequences of each scenario. A new computing framework, OMAM (ORIGEN-MAAP4-MMCS), has been developed and applied for assessing the risk of a reference plant as well as radiation source terms using the concept of risk triplet. The result of this study using the OMAM framework presented in this paper, can contribute to producing domestic nuclear power plant's risk data base as well as to establishing severe accident management plans.

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Cone-beam computed tomography: Time to move from ALARA to ALADA

  • Jaju, Prashant P.;Jaju, Sushma P.
    • Imaging Science in Dentistry
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    • v.45 no.4
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    • pp.263-265
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    • 2015
  • Cone-beam computed tomography (CBCT) is routinely recommended for dental diagnosis and treatment planning. CBCT exposes patients to less radiation than does conventional CT. Still, lack of proper education among dentists and specialists is resulting in improper referral for CBCT. In addition, aiming to generate high-quality images, operators may increase the radiation dose, which can expose the patient to unnecessary risk. This letter advocates appropriate radiation dosing during CBCT to the benefit of both patients and dentists, and supports moving from the concept of "as low as reasonably achievable" (ALARA) to "as low as diagnostically acceptable" (ALADA).

An Investigation of Radiation Heat Transfer on The Horizontal Fin of An External Fuel Tank by Flame of a Flying Flare (날아가는 섬광탄이 연료탱크 수평핀에 미치는 복사열전달 연구)

  • Jung, Daehan;Kang, Chihang;Kim, Sitae
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.2
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    • pp.197-203
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    • 2014
  • In this paper, the effect of unsteady radiation on the horizontal fin of an external fuel tank by flame of a flying flare was analysed to see the temperature increase of the fin and the thermal impact on the fin. Radiation between two surfaces was calculated using the concept of radiation resistance of surface and space including radiation, irradiation and shape factor for two flying trajectories of a flare, maximum temperature of 2200 K, emissivity of 0.95, flying velocity of 30 m/s, and thermal surface area of $0.01m^2$. The result shows that the temperature increase of the fin is 0.236 K, and the thermal effect on the fin is ignorable. And it was found that temperature is increased a little because small amount of heat energy can be radiated due to the short exposure time to the heat source.

Radiotherapy for Ovarian Cancers - Redefining the Role

  • Rai, Bhavana;Bansal, Anshuma;Patel, Firuza Darius;Sharma, Suresh Chander
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.12
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    • pp.4759-4763
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    • 2014
  • Radiation therapy in ovarian cancers has been considered an outdated concept for many years, mainly due to its toxicity and failure to show benefit in terms of survival. Chemotherapy has been extensively used after surgery for these cancers and it has almost replaced radiation therapy as an adjuvant treatment. Nevertheless, failures in ovarian cancers continue to occur even with the use of newer and effective chemotherapy regimens. About 70% patients demonstrate recurrence in the abdomen or pelvis after first line chemotherapy in ovarian cancers. With advances in technology and sophistication of radiation techniques, along with the molecular and biological knowledge of distinct histological subtypes, there is a need to redefine the role of radiation therapy. This review article focuses on the literature on use of radiation in ovarian cancers and its rationale and indications in the present day. For this, a literature pub med/medline search was performed from January 1975 to March 2014 to redefine the role of radiotherapy in ovarian cancers.

The Actual Status of Physics Teachers' Perception on the Concept of Radiation (물리 교사들의 방사선 개념에 대한 인식 실태)

  • Park, Sang-Tae;Choi, Hyuk-Joon;Kim, Jun-Tae;Jung, Ki-Ju;Lee, Hee-Bok;Yuk, Keun-Cheol
    • Journal of The Korean Association For Science Education
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    • v.25 no.5
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    • pp.603-609
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    • 2005
  • Students obtain most concepts through textbooks, and teaching-learning activities between teachers and students. Accordingly, if science teachers already have misconceptions they will inevitably affect students' scientific concept. This study found many problems in teachers' cognition on the concepts of nuclear radiation. Because 12th grade physics II is classified as an optional subject in the 7th curriculum, teachers have few chances to teach it and, more importantly, have difficulty in teaching it because of the need to prepare students for the university entrance examination. The concept of radiation must be taught correctly because of its emergence in the 'environment' unit of 10th grade Science. Finally, results from this study can help science teachers teach these difficult concepts more correctly. In addition, results can also be useful in in-service retraining programs.