• Title/Summary/Keyword: 이수체

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Dielectric and piezoelectric properties of PZT-polymer 3-3 type composite for ultrasonic transducer applications (초음파 트랜스듀서용 PZT-고분자 3-3형 복합압전체의 유전 및 압전특성)

  • 박정학;이수호;최헌일;사공건;배진호
    • Electrical & Electronic Materials
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    • v.9 no.2
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    • pp.146-151
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    • 1996
  • PZT powders were prepared by the molten salt synthesis method. The porous PZT ceramics were made from a mixture of PZT and polyvinylalcohol(PVA) by BURPS(Bumout Plastic Sphere) technique. The 3-3 type composites were fabricated by impregnating an sintered porous PZT ceramics with various polymer matrices. The relative permittivity of 3-3 type composite specimens was shown 860-1,100 smaller than that of solid PZT ceramics(2,100), and the dissipation factors of composite specimens were about 0.02 to 0.03. The piezoelectric coefficient d$_{33}$ of composite specimens(285-328*10$^{12}$ C/N) was comparable with that of single phase PZT specimens(364*10$^{-12}$ C/N). The thickness mode coupling factor k$_{t}$(O.5-0.6) of composite specimens was comparable with that of single phase PZT specimens(k$_{t}$-0.7), and the mechanical quality factor of composite specimens was smaller than 10, and thus these 3-3 type composite specimens would be believed as a good candidates for broad band transducer applications.ons.

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Radiated Emission / Susceptibility Tests for the KSLV-I 2nd Stage Engineering Model (KSLV-I 2단부 엔지니어링 모델 복사성 방사/감응 시험)

  • Ji, Ki-Man;Lee, Soo-Jin;Chung, Eui-Seung
    • Aerospace Engineering and Technology
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    • v.6 no.1
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    • pp.173-181
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    • 2007
  • Radiated emission / susceptibility performance of the KSLV-I 2nd stage which are controlled from the unit level to the system level should be examined and managed all over the frequency ranges in order to ensure the normal operation of the SC, the 1st stage of the KSLV-I, ground support equipments which are installed at the space center, and other wireless communication networks. Not only unintentional electric field emissions from the KSLV-I system and its subsystems should be restricted to the levels less than the limits specified in the EMC requirements, but also proper test and evaluation method should be established, respectively. In this paper, radiated emission/susceptibility test limits, method, and test results of the KSLV-I 2nd stage engineering model are presented.

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The Launch Operation Sequence through Remote Control of Bogie (보기 원격제어를 통한 발사 운용과정)

  • Lee, Chang-Bae;Seo, Jin-Ho;Lee, Soo-Jin;Chung, Eui-Seung
    • Aerospace Engineering and Technology
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    • v.7 no.2
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    • pp.144-150
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    • 2008
  • Bogie(The Launch vehicle transporter) is the special land transportation vehicle for the LV (Launch vehicle) which is used for not only the transportation-means of LV from LVAB(Launch Vehicle Assembly Building) to LP(Launch Pad) but also one of principal tools for launch operation sequence. Due to the multi-role of Bogie, The technical requirements of bogie are very complicated. Especially launch operation has performed with not only bogie but also many ground support equipments. So, it is impossible to establish technical requirements of bogie without whole understanding of launch operation. This paper was made for arranging whole launch operation sequence and technical requirements of bogie based on the this sequence.

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Crop proteomics: Practical method for high resolution of two-dimensional electrophoresis (작물 단백질체 분석을 위한 이차원 전기영동 사용법)

  • Kim, U.G.;Jung, Hwa-Jin;Lee, Su-Ji;Kim, Sun-Tae
    • Journal of Plant Biotechnology
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    • v.39 no.1
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    • pp.81-92
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    • 2012
  • Two-dimensional gel electrophoresis (2-DGE) is one of the most important technologies for high-resolution separation of proteins for proteomics. In this study, we present a detail 2-DGE protocol which allows detection and quantification of total plant proteins separated on gels to improve matching in image analysis. This protocol highlighted here may be useful for researchers, who like to first study for the development of protein biomarkers involved in development, biotic and abiotic stresses in plant.

Numerical analysis of cavitation behavior and noise using Eulerian-Lagrangian method (Eulerian-Lagrangian 기법을 이용한 캐비테이션 거동과 소음의 수치적 해석)

  • Seol Hanshin;Park Kwangkun;Lee Soogab
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.167-170
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    • 2004
  • 본 논문에서는 수중익 버블 캐비테이션과 날개 끝 볼텍스 캐비테이션의 거동 및 소음을 Eulerian-Lagrangian 기법을 이용하여 수치적으로 해석하였다. Eulerian-Lagrangian 기법은 캐비테이션 버블이 유동장에 미치는 영향이 거의 없다는 가정하에 유동장과 캐비테이션 거동을 일방으로 연계하여 해석하는 방식이다. 수중익 버블 캐비테이션 해석을 위한 유동장은 비압축성 RAMS 방정식을 해석하여 구하고 날개 끝 볼텍스 캐비테이션 유동장은 일반적 CFD 기법의 큰 수치 소산으로 그 특성이 잘 나타나지 않으므로 Sculley 볼텍스 모델을 이용하여 해석한다. 해석한 유동장 정보를 입력치로 하고 버블의 지배 방정식인 Rayleigh-Plesset 방정식과 Newton의 제2법칙에 근거한 궤적 방정식을 연계하여 캐비테이션의 성장-붕괴와 운동을 예측한다. 계산된 거동 정보를 이용하여 버블 캐비테이션과 날개 끝 볼텍스 캐비테이션의 소음을 예측하였다. 본 연구는 수중 운동체에서 발생하는 캐비테이션의 거동과 소음의 특성을 파악하고 그에 따른 대비책을 마련하는 기본 연구로서 활용할 수 있을 것이다.

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Reconstruction of Wide FOV Image from Hyperbolic Cylinder Mirror Camera (실린더형 쌍곡면 반사체 카메라 광각영상 복원)

  • Kim, Soon-Cheol;Yi, Soo-Yeong
    • The Journal of Korea Robotics Society
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    • v.10 no.3
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    • pp.146-153
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    • 2015
  • In order to contain as much information as possible in a single image, a wide FOV(Field-Of-View) imaging system is required. The catadioptric imaging system with hyperbolic cylinder mirror can acquire over 180 degree horizontal FOV realtime panorama image by using a conventional camera. Because the hyperbolic cylinder mirror has a curved surface in horizontal axis, the original image acquired from the imaging system has the geometrical distortion, which requires the image processing algorithm for reconstruction. In this paper, the image reconstruction algorithms for two cases are studied: (1) to obtain an image with uniform angular resolution and (2) to obtain horizontally rectilinear image. The image acquisition model of the hyperbolic cylinder mirror imaging system is analyzed by the geometrical optics and the image reconstruction algorithms are proposed based on the image acquisition model. To show the validity of the proposed algorithms, experiments are carried out and presented in this paper. The experimental results show that the reconstructed images have a uniform angular resolution and a rectilinear form in horizontal axis, which are natural to human.

약물(藥物)의 '승강부심(升降浮沈)' 이론과 방제상(方劑上)의 운용례(運用例)에 대한 연구

  • Kim, Yong-Jin;Jo, Hak-Jun
    • Journal of Korean Medical classics
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    • v.19 no.3
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    • pp.33-46
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    • 2006
  • 통과대약물적(通過對藥物的)'승강부심(升降浮沈)'이론화기재방제학적운용방면적연구득출여하결론(理論和其在方劑學的運用方面的硏究得出如下結論): 1. 대약물적(對藥物的)'승강부심(升降浮沈)'대래영향적인소유(帶來影響的因素有), 기미후박지음양(氣味厚薄之陰陽), 한열온경지사기(寒熱溫京之四氣), 산고감신함지오미(酸苦甘辛鹹之五味), 이급약용부위(以及藥用部位), 약물적재질(藥物的材質), 약물적생숙등(藥物的生熟等). 2. 재약성작용상가구분위(在藥性作用上可區分爲), 승부적약성구유소풍(升浮的藥性具有疏風), 산한(散寒), 선폐(宣肺), 투진(透疹), 승양(升陽), 통비(通痺), 최토(催吐), 개궁등작용(開窮等作用), 이침강약성구유통편(而沈降藥性具有通便), 사화(瀉火), 이수(利水), 진정안신(鎭靜安神), 평간개탕(平肝漑湯), 평단(平端), 강역(降逆), 고정(固精), 삽장(澁腸), 지대등자용(止帶等作用). 3. 근거재(根據在), ${\ulcorner}$의학입문(醫學入門) 본초(本草)${\lrcorner}$ 중장결고등인적이론(中張潔古等人的理論), 치풍문적약가귀납위'승'적작용(治風門的藥可歸納爲'升'的作用), 치열문적약가귀납위'심'적작용(治熱門的藥可歸納爲'沈'的作用), 치조문적약가귀납위'강'적작용(治操門的藥可歸納爲'降'的作用), 치한문적약가귀납위'부'적작용(治寒門的藥可歸納爲'浮'的作用), 단시실제상부동적'승강부심'작용시상혼재일기적(但是實際上不同的'升降浮沈'作用是相混在一起的). 4. 재(在) ${\ulcorner}$의학입문(醫學入門)${\lrcorner}$, ${\ulcorner}$의방집해(醫方集解)${\lrcorner}$, ${\ulcorner}$의방고(醫方考)${\lrcorner}$ 중구체응용등약물적승강부심이론(中具體應用等藥物的升降浮沈理論), 내설명료방제적조성원리(來說明了方劑的組成原理), 저일점적용어소유처방(這一點適用於所有處方), 단시주요국한어중기적허약혹심현부교(但是主要局限於中氣的虛弱或心賢不交), 음허화왕등(陰虛火旺等).

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A Study on the Exhaust Gas Created by Staged Combustion and Gas Generator Cycle LRE by Using CEA (CEA를 이용한 다단연소사이클 및 가스발생기 사이클 LRE 배출가스 성분 분석)

  • Moon, In-Sang;Moon, Il-Yoon;Lee, Soo-Yong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.863-866
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    • 2011
  • Recently environmental issue is more and more emphasized and 'Green Growth' became on of the key words of this Government. Based on this trend, the exhaust gases out of the gas generator cycle and the staged combustion cycle LRE whose propellants are kerosene and LOx were compared. For this purse, 8 tonf class of each cycle engine was designed and the amount and the components of the gases were investigated by using CEA. As expected, the staged combustion cycle engine generates less pollutants than the other cycle. In addition, the graphite that is generated by the gas generator can be reacted with the oxygen in the atmosphere creating additional pollutants.

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The Dependence of Temperature and Frequency for the Dissipation Factor in Liquid Dielectrics (액체절연체(실리콘유) 유전정접의 온도및 주파수의존성)

  • 이돈희;소병문;이수원;김왕곤;홍진웅
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1993.11a
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    • pp.85-89
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    • 1993
  • Silicone oil exhibits the properies of both organic and inorganic substances and, thus, it has many superior properties such as higher thermal resistance and lower thermal oxidation level when compared to other dielectric liquids. In order to investigate the dielectric characteristics, dielectric liquids of viscosity 1 [cSt] is chosen as the specimen and experiment is performed in the temperature range of 20∼65 [$^{\circ}C$] and frequency range of 30∼1${\times}$10$\^$6/ [Hz] respectively. As a result, the observed linear decrease in dissipation factor at the frequency range below 3 [kHz] is due to the influence of frequency, whereas the increase in dissipation factor at higher frequency range is contributed by electrode's resistance. At a fixed frequency of 30 [kHz], increasing temperature results in higher peak value and wide width of the absorption curve. This is due to the increase in dipole and viscosity. As temperature increases, dipole moment is decreased from 0.98 to 0.64 [debye]. The activation energy which causes the relaxation and loss of dielectric is obtained about 15 [kcal/mole].

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Patterns of Income and Household Expenses Arrangements and Determinants Within Dual-Income Families (맞벌이 가구의 수입관리 유형 및 가계비관리 유형과 영향요인)

  • Lee, Su-Jin
    • Journal of the Korean Home Economics Association
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    • v.48 no.10
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    • pp.51-64
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    • 2010
  • The purpose of this study was to demonstrate the patterns of income and household expense arrangements within dual-income families. The data was obtained from the F-GENS Korea Panel Survey of Ochanomizu University. The responses were gathered from both married and unmarried people, primarily in Seoul and the metropolitan area, of ages ranging from 25 to 44. The sample for this study was comprised of data from 399 double-income households. Crosstab and multinominal logistic regression models were used to analyze the data. The results were as follows. First, dual-income families choose a pooling system as their income arrangement. Second, variables determining the income arrangement were the husband's age, school attainment, annual average income, and average working hour per day. Third, variables that affected the household expenses arrangement included the husband's level of schooling attained and the husband’s job type. Fourth, the ideology of the economic community effected both the income and household expenses arrangement.