• 제목/요약/키워드: Rays

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NaI(Tl) Scintillator를 이용한 휴대용 방사선 검출 장치 구현에 대한 연구 (Research for realization of platform of portable radiation detector using NaI(Tl) Scintillator)

  • 이존휘;조율희;이윤호;임익찬;김영길
    • 한국정보통신학회논문지
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    • 제16권10호
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    • pp.2323-2328
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    • 2012
  • 전 세계적으로 해운물류 안전 보안체계가 강화됨에 따라 국가물류보안 체계 구축을 위한 유비쿼터스 기술 기반의 해운물류 안전 보안 핵심기술 개발이 이루어지고 있다. 현재까지의 U-기반 해운물류 안전보안 시스템 개발과 관련하여 X-선을 이용한 3차원 검색장치 즉, 화물검색장치 개발에 대한 핵심기술을 개발해 오고 있고, 추가적으로 감마선을 검출할 수 있는 휴대용 방사선 검출 장치의 개발 필요성이 높아지고 있다. 본 논문에서는 방사선에 의한 인체, 물체 및 공공상의 장해를 미연에 방지하기 위한 고속의 휴대용 방사선 검출 장치 플랫폼 구현에 대한 연구를 제안하고자 한다.

한국산 학치과(농어목) 어류 1 미기록종, Aspasma minima (First Record of a Clingfish, Aspasma minima (Perciformes: Gobiesocidae) from Korea)

  • 한송헌;김맹진;김병엽;최찬문;송춘복
    • 한국어류학회지
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    • 제20권3호
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    • pp.224-227
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    • 2008
  • 학치과(Family Gobiesocidae)에 속하는 Aspasma minima 1개체가 제주도 조천읍 함덕리 연안에서 처음 채집되어 형태형질을 조사하였다. 이 종은 등지느러미 기조수 6~9개, 뒷지느러미 기조수 5~9개, 가슴지느러미 기조수 20~24개, 그리고 몸과 머리에는 많은 붉은 점이 산재하고, 위턱의 뒤 가장자리가 눈의 앞부분까지 도달하지 않는 특징을 갖고 있다. 이 미기록종의 신한국명을 "꼬마학치"라고 명명하였다.

Observation Systems of Cherenkov Radiation from Water Phantom Irradiated with Co-60 Gamma-rays

  • Tabushi, Katsuyoshi;Koyama, Shuji;Homma, Mitsuhiko;Tamiya, Tadashi;Yajima, Mihoko;Imai, Kuniharu;Obata, Yasunori
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.123-125
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    • 2002
  • Blue light of Cherenkov radiation generated by electrons in transparent substances such as water and acrylic resin is well known generally. If students can easily observe the blue light at school, they may be impressed by the fascinating radiation. Four years ago, management of the Co-60 unit for radiotherapy was transferred to Nagoya University School of Health Sciences from a related hospital. We have examined whether or not the Cherenkov radiation in water from secondary electrons generated by Co-60 gamma-rays can be safely observed by eyes and photographs. First, the Cherenkov radiation in the water tank was led to the corridor outside the irradiation room by a mirror, and observed directly without any effect of the radiation exposure. Second, photographs of the Cherenkov radiation were taken under the conditions consisted of several irradiation fields and pass lengths of gamma-rays in water.

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Species Identification of Wood Coffins in Chosun Dynasty Period Excavated in Andong Area

  • Eorn, Young-Geun
    • Journal of the Korean Wood Science and Technology
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    • 제27권4호
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    • pp.15-19
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    • 1999
  • Three wood coffins of Chosun Dynasty period buried about 450 years ago were excavated in the sound condition in Andong area in the early 1998. The proprietors of wood coffins were grandparents, Mr. Myoung Jong Lee and Mrs. Mun, and their grandson, Mr. Eung Tae Lee, and the social standing of their family was known to belong to the nobility in those days by the clan genealogy. All the wood coffins investigated through light microscopy had same anatomical characteristics as follows: abrupt to somewhat abrupt tracheid transition from earlywood to latewood; normal longitudinal and horizontal resin canals with thin-walled epithelium; tylosoids in resin canals; bordered pits frequently in 1 row on radial walls of tracheids; 1 or 2 window-like pits per cross-field; uniseriate and fusiform rays; heterogeneous rays composed of body ray parenchyma cells and marginal ray tracheids or homgeneous rays composed of only ray tracheids; dentate ray tracheids; occasional trabeculae traversing tracheids in radial direction. Based on theses microscopic characteristics, all the wood coffins were identified to be Korean red pine (Pinus densiflora) or Korean black pine (Pinus thunbergii). Korean black pine growing naturally in coastal area might not be probable because the site of excavation, Andong area, was mountainous and inland area of Korea Thus, Korean red pine was thought to be the possible species for the wood coffins because of its natural distribution through the Korean Peninsula and the easy availability.

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한국 제주도에서 채집된 청줄돔과 어류 1미기록종, Chaetodontoplus melanosoma (New Record of the Black-Velvet Angelfish, Chaetodontoplus melanosoma (Pomacanthidae, Perciformes) from Korea)

  • 한송헌;김맹진;송춘복
    • 한국어류학회지
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    • 제27권3호
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    • pp.249-252
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    • 2015
  • 농어목 청줄돔과에 속하는 Chaetodontoplus melanosoma 1개체 (표준 체장 123.1 mm)가 2010년 2월 24일 제주도 사계연안의 삼중자망에서 처음으로 채집되었다. 이 종은 체측에 파란색 줄무늬가 없는 대신 멜라닌 색소가 잘 발달되어 있는 점, 눈 뒤에 반점이 없는 점, 그리고 가슴지느러미 기부에 검은색 반점을 가지는 점이 특징이다. 하지만, 청줄돔이 가지는 체측의 파란줄무늬가 이 종의 등지느러미에 희미하게 남아있으며 형태적으로도 유사하기 때문에 이 미기록종의 국명을 "검은청줄돔"으로 제안한다.

WALK-THROUGH VIEW FOR FTV WITH CIRCULAR CAMERA SETUP

  • Uemori, Takeshi;Yendo, Tomohiro;Tanimoto, Masayuki;Fujii, Toshiaki
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2009년도 IWAIT
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    • pp.727-731
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    • 2009
  • In this paper, we propose a method to generate a free viewpoint image using multi-viewpoint images which are taken by cameras arranged circularly. In past times, we have proposed the method to generate a free viewpoint image based on Ray-Space method. However, with that method, we can not generate a walk-through view seen from a virtual viewpoint among objects. The method we propose in this paper realizes the generation of such view. Our method gets information of the positions of objects using shape from silhouette method at first, and selects appropriate cameras which acquired rays needed for generating a virtual image. A free viewpoint image can be generated by collecting rays which pass over the focal point of a virtual camera. However, when the requested ray is not available, it is necessary to interpolate it from neighboring rays. Therefore, we estimate the depth of the objects from a virtual camera and interpolate ray information to generate the image. In the experiments with the virtual sequences which were captured at every 6 degrees, we set the virtual camera at user's choice and generated the image from that viewpoint successfully.

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한국산 얼록동사리(Odontobutis interrupta) 자치어의 골격발달 (Early Osteological Development of Larvae and Juveniles in the Korean Spotted Sleeper Odontobutis interrupta from Korea)

  • 박재민;한지형;윤성민;한경호
    • 한국수산과학회지
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    • 제50권4호
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    • pp.396-405
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    • 2017
  • We observed the osteological development in larvae and juveniles of Korean spotted sleeper Odontobutis interrupta bred in the laboratory in April 2014. Immediately after hatching, the prelarvae, which were about 4.27 mm long, showed ossification of the premaxillary bones in the upper jaw and the dentary and articular bones in the lower jaw. At 7.11 mm, the larvae showed complete fusion of the post-cleithra and ossification of the scapulae with the appearance of one hole. At 8.65 mm, the larvae showed ossification of seven ribs from the third abdominal vertebra and an increase in the length of the neural spine and hemal spine. The number of caudal fin rays increased to 19. At 11.9 mm, the juveniles showed ossification of three procurrent rays on the side of the parhypural bone as well as ossification of two procurrent rays on the side of the epural bone, indicating the complete ossification of all spicules.

방사선 조사선량에 따른 생쥐 난소의 조직화학적 변화 (Study of Histochemical Changes of Mouse Ovary Under X-ray Irradiation)

  • 윤철호
    • 대한방사선기술학회지:방사선기술과학
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    • 제29권4호
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    • pp.275-284
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    • 2006
  • 본 연구는 X-선을 생쥐 생체에 조사한 후, 방사선 조사선량에 따른 난소조직의 형태적 변화를 Masson's trichrome, 세망섬유 염색법 등의 조직화학반응을 확인한 결과 X-선을 조사한 난소조직은 방사선량이 증가함에 따라 성장 난포의 형태적 변화가 뚜렷하였으며, 특히 과립층세포의 변성에 의한 핵은 응축과 투명대의 변화가 현저하였다. 또한 Masson's trichrome 염색과 세망섬유 염색을 통한 조직화학반응의 결과 과립층세포의 변화와 난포기저막의 변형, 그리고 세망섬유의 비정상적 배열이 확인되었다.

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감마선 처리를 이용한 고무공장 폐수의 생물독성 저감 (Toxicity Reduction of Wastewater from a Rubber Products Manufacturing Factory by Gamma-ray Treatment)

  • 박은주;조훈제;조기종;김정규;정진호
    • 한국물환경학회지
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    • 제22권5호
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    • pp.913-918
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    • 2006
  • Both raw wastewater and effluent from a rubber products manufacturing factory were found to be toxic to Daphnia magna though the effluent satisfied current water quality standards. Thus, in order to reduce toxicity, advanced oxidation processes (AOPs) such as gamma-ray (${\gamma}-ray$) treatment and ozonation ($O_3$) were applied. A combined ${\gamma}-rays/O_3$ treatment at 20 kGy after coagulation significantly reduced toxicity of raw wastewater, changing 48-h toxic unit (TU) value from 201.21 to 23.92. However, toxicity of treated water was higher than that of effluent (TU = 12.15). This shows limitation of gamma-ray treatment to remove toxicity of raw wastewater. In case of effluent, the combined ${\gamma}-rays/O_3$ treatment at 20 kGy efficiently decomposed toxic compounds down to non toxic level. This work strongly supports the necessity of toxicity reduction evaluation as well as toxicity-based effluent management.

감마선을 이용한 테레프탈산과 에틸렌글리콜의 방사선처리 (Radiation Treatment of Terephthalic Acid and Ethylene Glycol by using Gamma-rays)

  • 이선미;조훈제;김정규;정진호
    • 한국물환경학회지
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    • 제20권5호
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    • pp.452-456
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    • 2004
  • Gamma-rays effectively decomposed TPA and EG, thus removal of $1.0{\times}10^{-3}$ M pollutants was near 65 and 95%, respectively, at an absorbed dose of 10 kGy. However, TOC removal in the radiation treatment was less than 5% due to a low transformation of both TPA and EG to $CO_2$. For TPA, gamma-ray treatment largely reduced biodegradability($BOD_5/COD$) by degrading TPA to non-biodegradable organic acids. This implies that the change of biodegradability should be considered when the radiation treatment is combined with conventional biological techniques. A weight-loss wastewater containing TPA and EG was also purified by gamma-ray treatment. Extraordinarily, biodegradability of the wastewater was increased at a low dose of 1 kGy. Though underlying mechanism was not clearly identified, this result stresses the effect of wastewater composition and absorbed dose on the biodegradability change.