• Title/Summary/Keyword: 환상형(環相型)

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액체금속로 SAILMER 개념 개발

  • 남호윤;이용범;김용균;최병해;김종만
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.10a
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    • pp.509-515
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    • 1997
  • 환상형 이중벽 증기발생기와 환상형 전자펌프 신개념을 개발하여 중간열교환계통과 소듐 배관이 없는 단순하고 밀집된 형태의 액체금속로인 SAILMER 노형 개념을 제안하였다. 금속핵연료를 사용하는 모듈형으로 증기발생기에서의 소듐과 물 반응사고에 대비한 연구와 제작기술을 제고시키면 이 노형은 경제성과 고유안전성을 동시에 구현할 수 있다.

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Optimal design of a concave annular array transducer to generate high intensity focused ultrasound (고강도 집속 초음파 발생용 오목한 환상형 배열 트랜스듀서의 최적설계)

  • Choi, Euna;Roh, Yongrae
    • The Journal of the Acoustical Society of Korea
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    • v.35 no.6
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    • pp.452-465
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    • 2016
  • In this study, the structure of a concave annular array transducer was optimized to generate high intensity focused ultrasound for medical therapeutic application. The transducer has a phased array structure composed of several concentric channels that have 40 mm as the radius of curvature. We derived theoretical equations to analyze the sound field of the transducer and verified the validity of the equations by comparing the results calculated by the equations with those from finite element analyses. We also checked the possibility of dynamic focusing at around the geometric focal point. Further, the level of a grating lobe occurring at an unwanted position in the transducer sound field was confirmed to be reducible through the relation between the number of channels and the frequency of the transducer. Hence, the structure of the transducer was optimized to place the main lobe within a specific range from the zenith while systematically reducing the level of the maximum sidelobe including the grating lobe. The designed structure showed the performance better than that targeted at all the focal points.

A Social Psychology of the Afterlife Views (내세관의 사회심리학: 일상생활과의 관련성을 중심으로)

  • Yoshiyuki Inumiya;Il-Ho Choi;Seong-Yeul Han
    • Korean Journal of Culture and Social Issue
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    • v.8 no.1
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    • pp.141-164
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    • 2002
  • The present study examined the variations in personality variables according to different types for the Korean view of the afterlife, including 'extinction type', 'the other world-oriented transmigration type', 'heaven/hell type' and 'obscurity type'. The results may be summarized as follows: (1) 'the other world-oriented transmigration type' and 'heaven/hell type' showed significantly stronger belief in a just world than 'extinction type', (2) 'extinction type' and 'obscurity type' showed more external attribution for accidents than 'heaven/hell type', (3) there was no difference in unrealistic optimism levels, (4) depending upon the types for the view of the afterlife, not only preferred self-enhancing biases but also positive illusions which related to life satisfaction were different, (5) 'extinction type' showed stronger risk-taking tendency than 'heaven/hell type'. These results were explained in terms of features that belong to each afterlife view. Finally, we discussed the limitation of this study and the directions for future study.

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도시 오픈스페이스를 활용한 그린네트워크 구축

  • 김기호;김수봉;조진희
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.05a
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    • pp.177-179
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    • 2003
  • 기존 자연녹지인 앞산, 금호강/낙동강, 와룡산과 대상지내 산재해 있는 공원녹지를 연결하여 환상형(環狀形)의 그린네트워크를 형성하였다. 그린네트워크 조성에 따른 기존 자연녹지와 공원녹지 사이의 연계 방안으로 도시내 오픈스페이스인 학교용지를 선택하고 이를 연결하는 방안을 제시하였다 공원녹지의 위치상 1면이상이 도로와 접하고 있어 이를 연계하기 위한 가로공간의 녹화를 추진하여 녹지축을 연결하는 방안을 제시하였다. 또한, 도시내 자연녹지 중 도시하천의 역할을 분석하여 본 결과, 대상지내 그린네트워크를 조성하기 위해서는 하천변을 녹화하는 계획을 추진하여야할 것으로 사료된다.

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High Aperture Efficiency nat Antenna using Annular Ring Resonators and Radial Waveguide feeder Network (환상형 공진기와 방사형 도파관 급전구조를 이용한 고효율 평면안테나에 관한 연구)

  • Jeong, Ki-Hyeok;Ra, Keuk-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.8A
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    • pp.688-696
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    • 2005
  • An antenna was designed and manufactured for the DBS receiver system. This antenna is a planar or flat antenna which shows many advantages over the conventional parabolic antenna such as higher aperture efficiency, easier installation and improved aesthetics to name a few. The antenna is a novel design employing microstrip annular ring resonating antenna elements and a radial waveguide feeder network. The LNB(Low Noise Blockdown Converter) is can integrate with the antenna iしt the back of the radial waveguide. The 35cm diameter antenna works at 31.8dBi minimum gain which implies an aperture efficiency of around $80\%$.

Establishment of Minimum Harvesting Time for the Girdled 'Campbell Early' Grape (환상박피된 '캠벨얼리' 포도의 최소 수확시기 설정)

  • Park, Seo-Jun;Cheong, Sung-Min;Kim, Seung-Heui;Ryou, Myung-Sang;Lee, Han-Chan;Jeong, Seok-Tae
    • Journal of Bio-Environment Control
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    • v.18 no.4
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    • pp.502-507
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    • 2009
  • This study was conducted to establish the minimum harvesting time of 'Campbell Early' grape with girdling of 8 years old vines by the investigation of fruit quality. Girdling was performed as 5~7mm width at 1.0m height with a Y-trellis system on July 5th at Gimcheon, Gyeongbuk province. Skin color, soluble solids contents, sugar content, organic acid, and titratable acidity were analyzed every seven days period after the girdling. From 14 days after the girdling, pericarp color changed quickly as compared to the control, and also decreased b value and increased a value of Hunter L were observed. The content of organic acids decreased quickly as 0.85% as compared to the control's one, 1.10%. Sugar-acid ratio increased rapidly from the 21days as 15.1 against 10.8 of the control at harvesting time. After 14days, sugar content was abruptly increased such as fructose and glucose, that is 7days faster than the control. In harvesting time, their contents were high as $64.5mg{\cdot}g^{-1}FW$ and $61.0mg{\cdot}g^{-1}FW$ as compared to $56.1mg{\cdot}g^{-1}FW$ and $53.7mg{\cdot}g^{-1}FW$ of the control respectively. Among the content of organic acids, malic acid decreased quickly than the control's one in coloring time. The content of tartaric acid was obviously lower as $4.13mg{\cdot}g^{-1}FW$ than the control's one, $5.96mg{\cdot}g^{-1}FW$ in harvesting time. From these results, we assume that the harvesting of girdled 'Campbell Early' grape should be started in 42days after the girdling, when sugar-acid ratio is above 15.

Detection of a Crack on a Plate by IDT Type Lamb Wave Sensors (IDT형 Lamb 파 센서에 의한 판상의 균열 검출)

  • Kim, Jun-Ho;Roh, Yong-Rae
    • The Journal of the Acoustical Society of Korea
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    • v.29 no.8
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    • pp.483-490
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    • 2010
  • In this paper, an Inter-Digital Transducer (IDT) type Lamb wave sensor is proposed to estimate the geometry and number of cracks on a plate structure, and its validity is checked through experiments. This IDT type sensor is more readily controllable than conventional patch type piezoelectric sensors to modify its operation frequency and directionality by altering its finger patterns. In this work, omni-directional annular IDT and highly directional rectangular IDT sensors are designed and fabricated. The IDT sensors are used to diagnose the length, number and orientation of cracks on an aluminum plate by measuring the amplitude and time of flight of Lamb waves. The results are analyzed to discuss the efficacy of the IDT sensors.

Cytogenetic evaluation of a patient with ring chromosome 9 presenting failure to thrive and developmental delay (성장부진과 발달지연을 보인 환아에서 확인된 환상 9번 염색체 1례의 세포유전학적인 연구)

  • Park, Yun Mi;Nho, Han Nae;Kim, Sook Za;Ahn, Young Min
    • Clinical and Experimental Pediatrics
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    • v.51 no.4
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    • pp.426-430
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    • 2008
  • We report clinical, cytogenetic, and fluorescence in situ hybridization (FISH) studies of a patient with ring chromosome 9. She presented with failure to thrive, facial dysmorphysm and mild psychomotor development delay in the absence of major malformations. Peripheral blood karyotype of the patient was 46,XX,r(9)(p24q34). G-band analysis suggested no loss of material in the ring chromosomes. FISH analysis using the subtelomere-specific sequences on chromosome 9p and 9q, revealed 46,XX,r(9)(p24q34),ish r(9)(D9S913-,D9S325+). Failure to detect any hybridization of a probe for the subtelomeric sequences in the ring 9p terminal suggested that this ring arose from breakage in the distal short arm. The cytogenetic and FISH data in our case provided further evidence for the existence of a "complete ring" phenotype with incomplete subtelomeric sequences.

Dynamical Properties of Ring Connection Neural Networks and Its Application (환상결합 신경회로망의 동적 성질과 응용)

  • 박철영
    • Journal of Korea Society of Industrial Information Systems
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    • v.4 no.1
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    • pp.68-76
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    • 1999
  • The intuitive understanding of the dynamic pattern generation in asymmetric networks may be useful for developing models of dynamic information processing. In this paper, dynamic behavior of the ring connection neural network in which each neuron is only to its nearest neurons with binary synaptic weights of ±1, has been inconnected vestigated Simulation results show that dynamic behavior of the network can be classified into only three categories: fixed points, limit cycles with basin and limit cycles with no basin. Furthermore, the number and the type of limit cycles generated by the networks have been derived through analytical method. The sufficient conditions for a state vector of n-neuron network to produce a limit cycle of n- or 2n-period are also given The results show that the estimated number of limit cycle is an exponential function of n. On the basis of this study, cyclic connection neural network may be capable of storing a large number of dynamic information.

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