• 대한전자공학회논문지
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• 제9권5호
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• pp.19-26
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• 1972

V.V.C다이오드를 사용한 수정주파수 변조방식에 대한 간단한 소개와 그의 변사직선성, 변조왜곡 및 중심주파수의 안정도등 제반특성이 휴대용 간이형 FM송신기 변체기로서 적합한지를 실험적결과로써 기각하였다. 또한 52.750MHz에서 직접주파수변조하는 단일채늘 송수신기 및 10.7MHz에서 순파수변조하고 채늘발진기에서 나오는 주파수와 합성하여 운용주파수로 하는 2채늘 송수신기(무조정으로40채늘)등 이종류의 송수신기를 시작품으로 제작히여 우수한 종합특성을 얻었으며 이로써 실용성을 입증하였다.

• Journal of applied mathematics & informatics
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• 제35권1_2호
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• pp.121-130
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• 2017

This study is concerned with the existence of positive solution for the following nonlinear elliptic system $$\{-M_1(\int_{\Omega}{\mid}x{\mid}^{-ap}{\mid}{\nabla}u{\mid}^pdx)div({\mid}x{\mid}^{-ap}{\mid}{\nabla}u{\mid}^{p-2}{\nabla}u)\\{\hfill{120}}={\mid}x{\mid}^{-(a+1)p+c_1}\({\alpha}_1A_1(x)f(v)+{\beta}_1B_1(x)h(u)\),\;x{\in}{\Omega},\\-M_2(\int_{\Omega}{\mid}x{\mid}^{-bq}{\mid}{\nabla}v{\mid}^qdx)div({\mid}x{\mid}^{-bq}{\mid}{\nabla}v{\mid}^{q-2}{\nabla}v)\\{\hfill{120}}={\mid}x{\mid}^{-(b+1)q+c_2}\({\alpha}_2A_2(x)g(u)+{\beta}_2B_2(x)k(v)\),\;x{\in}{\Omega},\\{u=v=0,\;x{\in}{\partial}{\Omega},$$ where ${\Omega}$ is a bounded smooth domain of ${\mathbb{R}}^N$ with $0{\in}{\Omega}$, 1 < p, q < N, $0{\leq}a$ < $\frac{N-p}{p}$, $0{\leq}b$ < $\frac{N-q}{q}$ and ${\alpha}_i,{\beta}_i,c_i$ are positive parameters. Here $M_i,A_i,B_i,f,g,h,k$ are continuous functions and we discuss the existence of positive solution when they satisfy certain additional conditions. Our approach is based on the sub and super solutions method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.530-533
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• 1998

In this paper, a new scheme of a boosted voltage generator (BVG) is designed for low powr DRAM's. The designed BVG can supply stable $V_{pp}$ using a new circuit operting method. This method controls charge pumping capability by switching the supply voltage and ring oscillator frequency of driving circuit, so the BVG can save area and reduce the powr dissipation during $V_{pp}$ maintaining period. The charge pumping circuit of the BVG suffers no $V_{T}$ loss and is to be applicable to low-voltage DRAM's. $V_{pp}$ level detecting circuit can detect constant value of $V_{pp}$ against temperature variation. The level of $V_{pp}$ varies -0.55%~0.098% during its maintaining period. Charge pumping circuit can make $V_{pp}$ level up to 2.95V with $V_{cc}$ =1.5V. The degecting level of $V_{pp}$ level detecting circuit changes -0.34% ~ 0.01% as temperature varies from -20 to 80.deg. C. The powr dissipation during V.$_{pp}$ maintaining period is 4.1mW.W.1mW.

• 품질경영학회지
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• 제25권2호
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• pp.15-27
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• 1997

This paper describes a highly accelerated life test (HALT, USPCBT) method for rapid qualification testing of STH PWB(Silver Through Hole Printed Wiring Boards). This method was carried out to be an alternative to the present time-consuming standard 1344 hours life testing(THB). The accelerated life test conditions were $121^{\circ}C$/95%R.H. at 50V bias and without bias. Their results are compared with those observed in the standard 1344 hours life test at $40^{\circ}C$/95%R.H. at 50V bias and without bias. The studies were focused on the samples time-to-failure as well as the associated conduction and failure mechanisms. The abrupt drop of insulation resistance is due to the absorption of water vapour. And the continuous drop of insulation resistance is due to the Ag migration. The ratios of time-to-failure of HALT(USPCBT) to THB were 25 and 11 at 50V bias and without bias respectively.

• 한국잠사곤충학회지
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• 제35권1호
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• pp.73-76
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• 1993

비형광성 염료인 Rhodamine-B를 누에의 기생파리인 Exorista bombysis(Louis)의 성충사료에 첨가하여 산란한 알을 표시한 실험으로써 비행 범위에 대한 조사를 행하였다. 이 방법은 시간이 절약되고 처리가 안전하며 표시된 알을 쉽게 관찰할 수 있으며, 또한 염료가 처리된 사료를 섭식한 파리의 치사율이나 산란성에는 나쁜 영향을 미치지 않았다. 그러나 이 파리가 산란한 알의 부화율을 저하시키는 경향이 있었다.

• 한국식품저장유통학회지
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• 제11권3호
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• pp.319-324
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• 2004

감귤과피의 열수, 에탄을 및 설탕 추출방법에 따른 항균활성을 비교 조사하였다 그 결과 감귤껍질의 열수 및 에탄올 추출물에서는 항균활성이 나타나지 않았으나, 설탕추출물에서 높은 항균활성을 나타내었다. 10$\%$(w/v) 설탕용액에서 9일간 추출하였을 때 8종의 균주 모두에서 항균활성이 가장 높았다 또한 최소저해농도는 S. aureus에서 0.5$\%$(v/v), B. subtilis, M. luteus 및 E. coli는 1.5%(viv), S. mutans는2.0$\%$(v/v) 각각 나타났다. 감귤 껄질 추출물은 40$\~$100$^{\circ}C$, 1시간 처리범위에서 항균성은 매우 안정하였으나, pH의 변화에서는 불안정하게 나타났다. 이상의 결과로 감귤껍질 추출물은 열안정성이 높은 항균성 소재로 개발이 기대되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1322_1323
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• 2009

The $V_{1.85}W_{0.15}O_5$ thin films deposited on Pt/Ti/$SiO_2$/Si substrates by RF sputtering method exhibited fairly good TCR and dielectric properties. It was found that film crystallinity, dielectric properties, and TCR properties were strongly dependent upon the annealing temperature. The dielectric constants of the $V_{1.85}W_{0.15}O_5$ thin films annealed at $400^{\circ}C$ were 38.11, with a dielectric loss of 1%, respectively. Also, the TCR values of the $V_{1.85}W_{0.15}O_5$ thin films annealed at $400^{\circ}C$ were about -3.45%/K.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 Techno-Fair 및 추계학술대회 논문집 전기물성,응용부문
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• pp.117-118
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• 2008

The $V_{1.85}W_{0.15}O_5$ thin films deposited on Pt/Ti/$SiO_2$/Si substrates by RF sputtering method exhibited fairly good TCR and dielectric properties. It was found that film crystallinity, dielectric properties, and TCR properties were strongly dependent upon the annealing temperature. The dielectric constants of the $V_{1.85}W_{0.15}O_5$ thin films annealed at $400^{\circ}C$ were 38.11, with a dielectric loss of 1%, respectively. Also, the TCR values of the $V_{1.85}W_{0.15}O_5$ thin films annealed at $400^{\circ}C$ were about -3.45%/K.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1248-1249
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• 2008

The $V_{1.8}W_{0.2}O_5$ thin films deposited on $Pt/Ti/SiO_2/Si$ substrates by RF sputtering method exhibited fairly good TCR and dielectric properties. It was found that film crystallinity, dielectric properties, and TCR properties were strongly dependent upon the annealing temperature. The dielectric constants of the $V_{1.8}W_{0.2}O_5$ thin films annealed at 400$^{\circ}C$ were 38.11, with a dielectric loss of 0.134, respectively. Also, the TCR values of the $V_{1.8}W_{0.2}O_5$ thin films annealed at 400$^{\circ}C$ were about -3.15%/K.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.961-963
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• 2000

Most of the application standard of the low-voltage devices have applied one the IEC standard another the UL standard. European union applied the IEC60947-1 standard has not exceed 1000V a.c. or 1500V d.c.. Therefore. it is necessary to the low-voltage device has expended for rated operational voltage with our products. The export of European market shall be made for the CE-Marking in accordance with IEC60947-1 ( Low-voltage switchgear and controlgear). We shall be considered for the requirement with the IEC standard. In this time to study for power supply system at EU ( European union. At that time for design and development in order to the construction and test method among the study for the rated insulation voltage at less then 690V.