• Title/Summary/Keyword: 산란재

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The Study on Ultrasound Physical Characteristic and Synthesis of Tissue Mimicking Materials Used New Materials (신소재를 사용한 인체조직모사물질의 합성과 초음파 물리적 특성에 관한 연구)

  • Ma, Sang-Chull;Kim, Hwa-Sun;Ann, Young-Man
    • Journal of radiological science and technology
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    • v.33 no.3
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    • pp.245-252
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    • 2010
  • This study analyzed speed of sound, impedance, attenuation coefficient in accordance with acoustic characteristic standard of body soft tissue corresponding with Annex DD of IEC standard 60601-2-37(2007) which is about tissue mimicking materials (TMM) synthesized by polyurethane as a main material and new type of n-type scatter materials. This study reached the following conclusion after analyzing and evaluating image characteristic with SONOACE 9900 c PRIME (MEDESON Co.) and brightness, maximum penetration with convex probe (2.5~5.0 MHz). When n-type scatter materials are increasingly synthesised 0~8% with prepolymer as a main material and polyol mixture as a catalyst, 1. The more scatter materials are increased, the more sound speed of TMM becomes closely similar to soft tissue. 2. The more scatter materials are decreased, the more acoustic impedance becomes closely similar to soft tissue. 3. The more scatter materials are increased, the more attenuation coefficient is increased. 4. The more scatter materials are increased, the more average brightness of images is increased, but there is threshold. 5. The maximum penetration becomes closely similar to soft tissue at the 6% TMM as a scatter material.

Characteristics and Influence of Scattering Radiation in Cultural Heritage Radiography (문화재 방사선 조사에서 발생하는 산란 방사선의 특성과 영향)

  • Song, Jung Il;Park, Young Hwan;Yu, Ji Hye
    • Journal of Conservation Science
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    • v.34 no.6
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    • pp.539-548
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    • 2018
  • This study was conducted to evaluate the effects of scattering radiation, which was not considered in the cultural Heritage radiography, by evaluating the relationship between the tube voltage (unit: kVp), film-floor-distance(FFD), and lead screen layout. The density (unit: D) of the test specimens and the scattered radiation increased with the tube voltage. The density of the test specimens showed an average deviation of 1.4 D; it was 0.17 D at 60 kVp, 1.54 D at 160 kVp, and 2.97 D at 220 kVp. The mean density of the scattered radiation was 0.10 D at 60 kVp, 0.40 D at 160 kVp, and 0.46 D at 220 kVp. The density tended to increase when the tube voltage ranged between 60 kVp and 160 kVp, as the FFD distance increased. However, a change in the permeation density was not observed for high voltages(160 kVp-220 kVp). Scattered radiation was observed when FFD was 50 mm, 100 mm, and 200 mm and no lead screen was used and the bottom surface was replaced with the lead screen. No scattered radiation was observed when FFD was 0 mm. The identification rate ranged from 2.08% to 2.67%, according to the FFD, for a 160 kVp tube voltage, and from 2.67% to 3.33% for a 220 kVp tube voltage.

가시망둑(Pseudoblennius cottoides)의 산란습성 및 초기생활사

  • 한경호;백승록;유동재;김광수;남윤석;황동석
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.05a
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    • pp.555-556
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    • 2001
  • 가시망둑, Psudoblennius cottoides는 쏨뱅이 目(Scorpaeniformes), 독중개科(Cottidae)에 속하는 연안성 어류이며, 우리나라 남부와 제주도 연해 및 일본 각지 연해안에 분포한다(정, 1977; 김 등, 2001). 가시망둑에 대한 연구는 우리나라에서는 없고, 일본에서는 가시망둑의 산란(Shiogaki and Dotsu, 1974)과 난 및 자치어의 발달(Kimura et al., 1987)이 있으나 이들 연구 모두 자연에서 채집된 가시망둑의 어미를 사육수조내에서 순치하여 인위적으로 수정난을 획득하였기 때문에 자연상태에서의 정확한 산란습성을 밝히지 못하였다. (중략)

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A Study on Scattering Center Extraction Using Full Polarimetric Data (다중편파 데이터를 이용한 표적 산란점 추출에 대한 연구)

  • Jeong, Seong-Jae;Lee, Seung-Jae;Kim, Kyung-Tae
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.27 no.5
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    • pp.463-470
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    • 2016
  • In this paper, we introduce a method of scattering centers extraction using the polarimetric data. VIRAF software based on the PO (Physical Optics) and PTD(Physical Theory of Diffraction) were used to calculate the surface scattering and the edge or wedge scattering, respectively. In addition, by using the unitary transformation, 4-channel data based on the linear polarization basis were converted to 2-channel data based on the left/vertical-circular polarization basis, leading to data compression coherently. The scattering mechanism was analyzed in terms of the polarization states and different look angles by using the scattering center of a target extracted by the 2D RELAX algorithm.

레이저 기반 플라즈마 진단

  • Seo, Byeong-Hun;Kim, Jeong-Hyeong;Seong, Dae-Jin;Yu, Sin-Jae
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.94.1-94.1
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    • 2016
  • 레이저 진단은 플라즈마 진단법 중 가정 정확한 진단법으로 알려져 있다. 특히 진단이 까다로운 고밀도, 자기장, 고압 환경에서도 그 측정 결과가 신뢰성 있다고 잘 알려져 있다. 본 특별 심포지엄에서는 중 성종을 측정 할 수 있는 레일레이 산란과 자유 전자를 측정 할 수 있는 톰슨 산란, 그리고 분자를 측정할 수 있는 라만 산란을 중심으로 발표 할 것이다. 또한 특정 준위를 갖는 원자 및 분자의 거동을 측정할 수 있는 레이저 유도 형광에 대해서도 간단히 발표 할 것이다. 그밖에 레이저 진단의 종류, 원리 등을 설명 하고 한국표준과학연구원에서 이루어 진고 있는 연구 결과에 대해 발표 할 것이다.

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계분의 재이용

  • 하워드 C. 친델
    • KOREAN POULTRY JOURNAL
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    • v.3 no.12 s.26
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    • pp.44-46
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    • 1971
  • 탈수건조된 계분은 산란계의 사료로서 여러번 재이용 할수 있다는 충격적인 실험연구보고가 미국 미쉬간대학의 친델박사에 의하여 발표되어 이를 소개하고자 한다. 탈수건조된 계분은 계분건조기에 의해서 제조된 것이므로 국내에서의 즉각적인 활용은 힘드리라고 예상되나 사료원료의 80$\%$이상을 수입하는 우리나라에서는 한번 음미해 볼 가치가 있어 옮겨보았다. 이글은 미국 폴트리$\cdot$다이제스트 1971년 5월호에서 전재한것임을 밝혀둔다.

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Effect of Some Environmental Factors on Oviposition and Developmental Characteristic of Protaetia brevitarsis and Allomyrina dichotoma (흰점박이꽃무지와 장수풍뎅이의 산란과 발육에 미치는 환경요인)

  • Kim, Ha-Gon;Kang, Kyung-Hong;Hwang, Chang-Yeon
    • Korean journal of applied entomology
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    • v.44 no.4 s.141
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    • pp.283-286
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    • 2005
  • This study was carried out to obtain information about a several environmental factors influencing on the bionomical characteristics of Protaetia brevitarsis and Allomyrina dichotoma, which have been used for an important traditional medicinal stuffs. The moisture contents of humus affected the oviposition of P. brevitarsis and A. dichotoma, showing a suitable condition in range of $65{\sim}75%$. Very high or very low moisture condition in humus decreased the egg laying of P. brevitarsis and A. dichotoma, Also, moisture condition of humus was an important factor influencing on the egg and larval survival, egg developmental period, and feeding activity of P. brevitarsis and A. dichotoma.