• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.250_251
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• 2009

IEC 61850 based substation automation system mainly consists of human machine interface as a client and a various of IEDs as a server. Both of them should require the field testing for performance verification including IEC 61850 communication services. This means that the test can assure the interoperability of IEC 61850 based substation automation system consisted of multi vendor's products. This paper shows a research result on the field test of the IEC 61850 based HMI and IEDs. And it proposes some engineering solutions for the system implementation.

• 한국컴퓨터산업학회논문지
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• 제2권11호
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• pp.1477-1482
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• 2001

본 논문에서는 개인휴대통신(PCS)의 최소 규격인 J-STD-018을 기준으로, 높은 이득과 낮은 제 3고조파 차단점을 갖는 수동 더블 밸런스 혼합기와 중간 주파 증폭기로 구성된 수신 시스템을 구성하여 수신 파라미터를 시뮬레이션 결과, 수신감도 규격의 파라미터인 잡음지수는 $E_b/N_t=6$일 때 6.746dB이고 상호변조 스퓨리어스 응답 감쇄 규격의 파라미터인 3차 고조파 차단점은 -11.358dBm이었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.239-240
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• 2008

Korea Electric Power Research Institute has being carried out an IEC 61580 communication service test on IED trial products developed related to power IT project, "Development of Prototype for Advanced Substation Automation System based on the Digital Control Technology". This paper describes GOOSE testing, one of the IEC 61850 conformance testing items, which consists of 14 publish and subscribe test cases.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2009년도 춘계학술대회 논문집
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• pp.259-262
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• 2009

IEC 61850 based substation automation system mainly consists of human machine interface and a various of IEDs in charge of protective and control functions of the substation. Both of them should require the performance verification of IEC 61850 communication services because their communication relation is the same as client and server throughout the digital network. This paper shows a research result on the testing method of basic communication interface of the IEC 61850 based client, which was implemented by the analysis of real communication between HMI and IED of IEC 61850 based substation automation system and refereed to IED IEC 61850 conformance test procedures.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.189-192
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• 1988

Nitrided oxides have been investigated recently for application as a replacement for thermally grown $SiO_2$ in MIS devices. In this paper, thin oxides were nitrided in $N_2$ Plasma ambient. With the measurement of the equivalent paralled conductance and capacitance by the using coductance technique, the characterization of Si-SiON interface is developed. The interface state density of Si-SiON is obtained by $1{\times}10^{11}{\sim}9{\times}10^{11}(eV^{-1}Cm^{-2})$. After${\pm}$B-T stress is performed on the sample, the interface state density gets increased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 전문대학교육위원
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• pp.134-136
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• 2004

The results of investigations of $Ag_2Te$ crystal is presented. $Ag_2Te$ crystal was grown by the Bridgman method. The $Ag_2Te$ crystal was an monoclinic structure with lattice constance a = 8.1686 A, b = 9.0425 ${{\AA}}$, c = 8.0065 ${{\AA}}$. Hall effect shows a n-type conductivity in the $Ag_2Te$ crystal. The electrical resistivity values was $1.080e^{-3}{\Omega}cm$ and electron mobility was $-5.48{\times}10^3cm^2/V{\cdot}sec$ at room temperature(RT).

• 전자공학회논문지D
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• 제35D권6호
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• pp.21-27
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• 1998

E-beam 장비로 ZnS:Mn/Zns:Tb 2층 구조의 TFEL 소자를 제작하여 전기, 광학적 특성을 조사하였다. ITO 투명전극과 ATO 절연체가 증착된 유리기판(corning 7059 glass) 위에 E-beam 장비를 이용하여 ZnS:Mn, ZnS:Tb 형광체를 각각 3000 A로 증착하여 총 두께 6000 Å 갖도록 제작하였다. ZnS:Mn/ZnS:Tb TFEL 소자의 스펙트럼은 Mn/sup 2+/ 이온과 Tb/sup 3+/ 이온의 고유한 발광 스펙트럼을 모두 포함하여 540㎚에서 640㎚에 이르는 매우 넓은 범위의 발광 스펙트럼을 나타내었다. 휘도는 인가전압의 크기가 112V에서부터 급격히 증가하여 155 V에서 포화 휘도 1025 Cd/㎡를 나타내었고 최대 전압 185 V에서의 휘도는 2080 Cd/㎡이었다. Capacitance-voltage(C-V) 및 transferred charge-phosphor voltage(Q/sub t/-V/sub p/) 특성으로부터 형광층 capacitance (C/sub p/)와 절연층 capacitance (C/sub i/)가 각각 13.5 nF/㎠, 60 nF/㎠됨을 알 수 있었고, 인가전압의 최대치를 155 V에서 185 V로 증가시킬수록 TFEL 소자의 문턱전압(V/sub thl/)이 126 V에서 93 V로 감소함을 알 수 있었다. 이것은 인가전압을 증가시킬수록 polarization charge가 증가되고 polarization charge에 의해 형성된 형광체 내부전압이 증가되었기에 문턱전압이 감소한 것이다. 또한 처음으로 문턱전압에 관한 수식을 제안하였으며 문턱전압의 이론치와 실험치가 일치하는 것을 확인하였다.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2002년도 추계학술대회 발표 논문집
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• pp.85-90
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• 2002

$RuO_2$/GaN and related contacts were investigated for Schottky contacts in GaN-Based optical and electronic devices. We demonstrated that an $RuO_2$ film forms a stable Schottky contact on a GaN layer with a barrier height (${\Phi}_B$) of 1.46 eV and transmittance of 70% in the visible and near UV region. $RuO_2$/GaN Schottky diode showed a breakdown at over -50V and leakage current of only 0.3 nA at -5V. The $RuO_2$/GaN Schottky type photodetector had the UV/Visible rejection ratio of over $10^5$ and the responsivity of 0.23 A/W at 330 nm. The $RuO_2$ gate AlGaN/GaN EFET exhibited high drain current ($I_d$) of 689.3 mA/mm and high transconductance ($g_m$) of 197.4 mS/mm. Cut-Off frequency ($f_t$) and maximum operating frequency ($f_{max}$) were measured as 27.0 GHz and 45.5 GHz, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제25권12호
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• pp.1726-1733
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• 2012

The effect of genotype, fibre level and fibre source on gut morphology, environment and microflora was studied using 18 Mong Cai (MC) and 18 Landrace${\times}$Yorkshire (LY) pigs, aged around 60 d. The diets were based on maize, rice bran, soybean meal, fish meal and soybean oil, and cassava residue (CR) or brewer's grain (BG) as fibrous ingredient sources in the high-fibre diets (HF). A low-fibre diet (LF), containing around 200 g NDF/kg dry matter (DM), was formulated without CR and BG as feed ingredients. The HF diets (HF-CR and HF-BG) were formulated to contain around 270 g NDF/kg DM. The experiment was arranged according to a $2{\times}3$ factorial completely randomized design with six replications, and lasted 30 d. Crypt density in ileum was lowest (p<0.05) and villus height in jejunum and ileum were the greatest (p<0.05) in pigs fed diet HF-BG. Villus width in ileum was greatest in pigs fed diets HF-CR and HF-BG (p<0.05). Lactic acid bacteria (LAB) counts in stomach were greatest (p<0.05) and E. coli counts in ileum and colon were lowest (p<0.05) in pigs fed diet HF-CR. The concentration of total organic acids in ileum, caecum and colon were greatest (p<0.05), and pH in ileum and colon were lowest (p<0.05) in pigs fed diet HF-CR. Crypt density in ileum was lowest, and villus height in ileum and villus width in jejunum and ileum was greatest in LY pigs (p<0.05). LAB counts in stomach and ileum were greatest, and E. coli counts in ileum were lowest in MC pigs (p<0.05). The concentration of total organic acids in ileum, caecum and colon were greatest (p<0.05) and pH lowest (p<0.05) in MC pigs.

• Asian-Australasian Journal of Animal Sciences
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• 제24권5호
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• pp.643-649
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• 2011

The objective of this study was to determine the effect of feeding direct-fed microbials (DFM) on the growth performance and prophylaxis of calf diarrhea during the pre-weaning period as an alternative to antibiotics. A multi-species DFM was formulated including three lactic acid bacteria (Lactobacillus salivarius Ls29, Pediococcus acidilactia Pa175, and L. plantarum Lp177), three Bacillus strains (B. subtilis T4, B. polymyxa T1 and SM2), one yeast, Saccharomyces boulardii, and a nonpathogenic E. coli Nissle 1917. Lactic acid bacteria and Bacillus strains were selected based on the antibacterial activity against various animal pathogens, especially pathogenic E. coli using agar diffusion methods in vitro. Test and control groups were fed milk replacer and calf starter supplemented with DFM ($10^9$ cfu each of eight species/d/head, n = 29) or with antibiotics (0.1% neomycin sulfate in milk replacer and Colistin 0.08% and Oxyneo 110/110 0.1% in calf starter, n = 15), respectively. Overall fecal score and the incidence rate of diarrhea were reduced in the DFM group compared to the antibiotics one. About 40% of calves in antibiotic group suffered from diarrhea while in DFM group only 14% showed diarrhea. There was no difference in the average daily gain and feed efficiency of two groups. The hematological levels of calves were all within the normal range with no significant difference. In conclusion, the feeding of multispecies DFM during the pre-weaning period could reduce calf diarrhea and there was no difference in the growth performance between the groups, thus showing the potential as an alternative to antibiotics.