• Title/Summary/Keyword: 산란점

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개불, Urechis unicinctus 유생의 수온과 염분 내성

  • 강경호;김재민
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.05a
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    • pp.620-621
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    • 2001
  • 개불류는 연안의 사니질에서 쉽게 발견되며 그 종류의 수나 자원량이 풍부한 저서 동물군이다. 이들은 번식력이 강하고 저질에 U자형의 굴을 들어 해수를 순환하게 함으로써 유기성분을 변화시켜 저질을 정화시키기도 하는 등, 연안생태계에서 매우 중요한 위치를 점하고 있다. 개불의 양식기술을 개발하기 위해서는 우선적으로 어미의 확보 및 산란유발, 난발생 및 유생사육 등에 관한 생물학적인 기초자료가 필요하게 된다. (중략)

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육계농장에서의 살모넬라 위생대책

  • 윤병선
    • KOREAN POULTRY JOURNAL
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    • v.34 no.5 s.391
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    • pp.79-82
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    • 2002
  • 육계농장에서는 SE(Salmonella Enteritidis)감염도 있지만, 오히려 SE이외의 여러 가지 요인에 의한 혈청형 살모넬라에 오염되는 경우가 많다. 현재 육계농장에서는 계군을 살모넬라로부터 완전히 차단하는 것은 어렵다고 생각하고 있고, WHO에서도 살모넬라 오염을 가능한 한 감소시키는 쪽으로 살모넬라 대책의 지침으로 정하고 있다. 그러나, SE 및 ST(Salmonella Typhimurium)등 사람에게 병원성을 나타내는 혈청형에 의한 계군의 살모넬라 감염오염은 공중위생의 견지에서 완전히 제거하지 않으면 안되다. 여기에서 출하 및 수송시의 대책, 사료의 살모넬라 오염의 중요성 등 산란계와는 다른 점을 지적하면서 기하고자 한다. 일상의 위생관리에 관한 양계장에서의 대책과 살모넬라 검사법에 대하여는 제외하였다.

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Analysis of Surface Dose Refer to Distance between Beam Spoiler and Patient in Total Body Irradiation (전신방사선조사(Total Body Irradiation) 시 Beam Spoiler와 환자 간의 거리에 관한 고찰)

  • Choi, Jong-Hwan;Kim, Jong-Sik;Choi, Ji-Min;Shin, Eun-Hyuk;Song, Ki-Won;Park, Young-Hwan
    • The Journal of Korean Society for Radiation Therapy
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    • v.19 no.1
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    • pp.51-54
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    • 2007
  • Purpose: Total body irradiation is used to kill the total malignant cell and for immunosuppression component of preparatory regimens for bone-marrow restitution of patients. Beam spoiler is used to increase the dose to the superficial tissues. This paper finds the property of the distance between beam spoiler and patient. Materials and Methods: Set-up conditions are 6 MV-Xray, 300 MU, SAD = 400 cm, field size = $40{\times}40cm^2$. The parallel plate chamber located in surface, midpoint and exit of solid water phantom. The surface dose is measured while the distance between beam spoiler and patient is altered. Because it should be found proper distance. The solid water phantom is fixer and beam spoiler is moving. Results: Central dose of phantom is 10.7 cGy and exit dose is 6.7 cGy. In case of distance of 50 cm to 60 cm between beam spoiler and solid water phantom, incidence dose is $14.58{\sim}14.92cGy$. Therefore, The surface dose was measured $99.4{\sim}101%$ with got near most to the prescription dose. Conclusion: In clinical case, distance between beam spoiler and patient affect surface dose. If once $50{\sim}60cm$ of distance between beam spoiler and patient, surface dose of patient got near prescription dose. It would be taken distance between beam spoiler and patient into account in clinical therapy.

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Validation of Sea Surface Wind Estimated from KOMPSAT-5 Backscattering Coefficient Data (KOMPSAT-5 후방산란계수 자료로 산출된 해상풍 검증)

  • Jang, Jae-Cheol;Park, Kyung-Ae;Yang, Dochul
    • Korean Journal of Remote Sensing
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    • v.34 no.6_3
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    • pp.1383-1398
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    • 2018
  • Sea surface wind is one of the most fundamental variables for understanding diverse marine phenomena. Although scatterometers have produced global wind field data since the early 1990's, the data has been used limitedly in oceanic applications due to it slow spatial resolution, especially at coastal regions. Synthetic Aperture Radar (SAR) is capable to produce high resolution wind field data. KOMPSAT-5 is the first Korean satellite equipped with X-band SAR instrument and is able to retrieve the sea surface wind. This study presents the validation results of sea surface wind derived from the KOMPSAT-5 backscattering coefficient data for the first time. We collected 18 KOMPSAT-5 ES mode data to produce a matchup database collocated with buoy stations. In order to calculate the accurate wind speed, we preprocessed the SAR data, including land masking, speckle noise reduction, and ship detection, and converted the in-situ wind to 10-m neutral wind as reference wind data using Liu-Katsaros-Businger (LKB) model. The sea surface winds based on XMOD2 show root-mean-square errors of about $2.41-2.74m\;s^{-1}$ depending on backscattering coefficient conversion equations. In-depth analyses on the wind speed errors derived from KOMPSAT-5 backscattering coefficient data reveal the existence of diverse potential error factors such as image quality related to range ambiguity, discrete and discontinuous distribution of incidence angle, change in marine atmospheric environment, impacts on atmospheric gravity waves, ocean wave spectrum, and internal wave.

Effect of a probiotic mixture on egg quality and egg production in laying hens (복합생균제가 산란계의 생산성, 계란품질 및 악취저감에 미치는 영향)

  • Shin, JS;Um, KH;Lee, JY;Choi, YS;Park, HJ;Lee, HS;Park, BS
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.3
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    • pp.748-757
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    • 2019
  • The objective of the present study was to evaluate effects of probiotic mixture (PM) including Bacillus subtillus, Streptomyces galilaeus and Sphingobacteriaceae on egg production, egg quality, and eliminating odor in laying hens. A total of 240 Hy-Line Brown laying hens (50 wks of age) were divided into four treatment groups (60 replicates of birds, each) in completely randomized design. Groups were assigned to four experimental diets: CON (a basal diet of no PM additive as control), basal diet supplemented with either CP3 (0.3% commercial probiotics), PM3 (0.3% PM), or PM5 (0.5% PM 0.5). Data of egg production and egg quality were obtained during 6 weeks of experimental period. Egg production, Haugh unit, shell thickness, breaking strength, yolk color, and albumin high were significantly increased in CP3 and PM3 compared to those in CON and CP3. Ammonia levels and numbers of E. coli, total aerobic bacteria, Coliform, and Salmonella in feces were significantly increased in order of CON>CP3>PM3>PM5. The present study indicates that addition of 0.3% probiotic mixture including B. subtillus, S. galilaeus and Sphingobacteriaceae to diets may improve egg production, egg quality, and eliminate fecal ammonia of laying hens.

A Study on the Cartesian Boundary Condition of curved Walls in Computational Aeroacoustics Scheme (전산공력음향학에서 직교좌표를 이용한 곡면에서의 경계조건에 대한 고찰)

  • Bin Jonghoon;Cheong Cheolung;Lee Soogab
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.299-302
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    • 2000
  • 본 연구에서는 원형실린더에 의한 음향파의 산란현상을 전산공력음향학 기법을 이용하여 계산하였다. 특히 전산공력음항학에서 정확도를 위해 요구되는 좌표의 직교성을 유지하기 위해서 그에 대한 적절한 관계식을 유도하였으며 정확성의 검증을 위해서 수치적인 해를 이론적인 해와 비교, 분석하였다. 공간차분법으로는 Taylor 전개를 통하여 차 정확도를 가진 차분법을 바탕으로 주파수 공간에서 최적화 된 DRP(Dispersion Relation Preserving) 기법을 사용하였으며, 시간차분법으로는 Adams-Bashford 방법을 기준으로 최적화된 4단계 외재적(explicit) 적분방법을 사용하였다 벽면 경계조건으로는 가상점 개념을 이용한 경계조건을 사용하였으며 원방 경계조건으로서는 선형화 된 Euler 방정식의 점근해(Asymptotic Solution)을 이용한 방사경계조건(Radiation Boundary Condition)을 사용하였다.

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Development of the 3 Dimensional ZnO Nanostructures for the Highly Efficient Quantum Dot Sensitized Solar Cells

  • Kim, Hui-Jin;Yong, Gi-Jung
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.672-672
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    • 2013
  • 본 연구에서는 수열합성법을 기반으로 한 3차원 ZnO 나노구조의 합성을 통해 효율적인 양자점 감응형 태양전지로의 응용을 하고 그 특성을 평가하였다. 기존의 1차원 ZnO 나노구조의 경우 높은 전자이동도와 구조적으로 얻을 수 있는 방향성 있는 전자의 효율적인 전달을 통해 효과적인 광전극으로 많은 관심을 받아왔다. 하지만 나노파티클 기반의 필름에 비해 표면적이 크게 떨어지기 때문에 효과적인 흡광이 어렵다는 단점이 존재하여 높은 효율특성을 내지는 못하였다. 본 연구에서는 이러한 단점을 극복하면서 기존 ZnO 나노선의 장점을 극대화 하기 위해 성장시킨 ZnO 나노선 위에 추가적으로 가지를 형성하여 표면적 향상과 효과적인 전자전달 특성을 얻고자 하였다. 3차원 ZnO 나노구조는citrate 계열의 capping agent의 첨가를 통한 수열 합성법을 통해 1차원의 ZnO 나노선 위에 nanosheet 형식의 가지를 형성하였고 이는 빛의 효과적인 산란특성 및 표면적 향상을 통한 CdS, CdSe의 양자점 증착량을 증가시키는 효과를 얻을 수 있었다. 이러한 태양전지의 소자 특성은 SEM, TEM을 통한 구조 특성평가 및 DRS, J-V curve 및 IPCE를 통한 광학적 특성평가를 통해 확인하였다.

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First Record of the Goby Gymnogobius taranetzi (Perciformes: Gobiidae) from Korea (한국산 망둑어과(농어목) 어류 1미기록종, Gymnogobius taranetzi)

  • Lee, Yong-Joo
    • Korean Journal of Ichthyology
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    • v.23 no.3
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    • pp.246-249
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    • 2011
  • Twenty five specimens (40.8~58.4 mm SL) of Gymnogobius taranetzi (Family Gobiidae) were collected from the estuary of Samcheok-si and Yangyang-gun, Gangwon-do, Korea. This species is distinguished from other Gymnogobius species by oculoscapular canals not extending anteriorly through interorbital space, but replaced by rows of sensory papillae; oculoscapular canal pore C is absent; some yellow bands on body in female with breeding color. The new Korean name "Dong-hae-nal-mang-duk" is proposed for this species.

Diffraction of Electromagnetic Waves by Right Angle Dielectric Wedge (직각 쐐기형 유전분에 의한 전자파 회절)

  • Ju, Chang-Seong;Ra, Jeong-Ung;Sin, Sang-Yeong
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.18 no.5
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    • pp.35-45
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    • 1981
  • An asymptotic solution of electromagnetic waves scattered by a right-angled dielectric wedge for plane wave incidence is obtained. Scattered fields are constructed by waves reflected and refracted from dielectric interfaces (geometric-optical fields) and a cylindrical wave diffracted from the edge. The edge diffracted field is obtained by adding a correction to the edge diffraction of physical optics approximation, where the correction field is calculated by solving a dual series equation amenable to simple numerical calculation. Validity of this result is assured by two limits of relative dielectric constant $\varepsilon$ of the wedge. The total asymptotic field calculated results in a Rawlins' Neumann series solution for small $\varepsilon$, and the edge diffraction pattern is shown to approach that of a perfectly conducting wedge for large $\varepsilon$. Calculated field patterns are presented and the accuracy of physical optics approximation is discussed.

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A Design and Fabrication of Multiple Scattering Points Generator for High Range Resolution Radar (고해상도 레이더용 다중산란점 발생장치의 설계 및 제작)

  • Lee, Ho-Joon;Kim, Youn-Jin;Yoon, Seung-Gu;Jeong, Hae-Chang;Kong, Deok-Kyu;Yi, Jae-Woong;Byun, Young-Jin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.5
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    • pp.590-597
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    • 2016
  • We designed the multiple scattering points generation system to simulate an actual situation of target signal for high range resolution radar system. This provides replicating the target signals and controlling the status of target signals for radar system. This is composed transmit antenna and multi target generator. Transmit antenna is waveguide array antenna and multi target generator has signal distribution module and control & power module. Multi target generator is able to provide the high isolation and variable output power. Moreover, in order to monitor all output signals of the multi target generator, the flows of signals are programed in control & power module. The performance is demonstrated using experimented results of high range resolution radar.