• 기술사
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• 제27권3호
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• pp.121-131
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• 1994

3차원 자유 형상 곡면으로 이루어진 선형을 부분적으로 표현하기란 매우 힘들다. 선박 설계에 컴퓨터를 이용한 기술이 적용되기 시작하면서, 기하학적 모델링 기법이 개발되어 왔다. 선형 모델링에서,곡률 변화가 심한 선체 곡면의 국부적인 곡면 형상을 Blending 기법을 써서 표현하는 연구는 이루어지지 않았다. Blend곡면을 써서, 설계시에 도면상에 표시되는 작은 곡면을 부드럽게 표현하는 방법을, 선체표면과 돌출된 접합 부분을 Blending 하고져 하였다. 본 연구에서는, 두개의 Base곡면에 Blend반지름을 입력 했을 때, Blend곡면에 Blending방법을 이용하여 공간 좌표인 Offsets 데이터를 얻을 수 있도록 선박 설계에 적용하여 보았다.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.978-983
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• 2014

The polymer nano composite possess good priority recently for engineering applications. Especially the electrical insulating materials attract the high performance of nano composites. In this work the ballmill synthesiation process of nano sized Alumina ($Al_2O_3$), the preparation of new nano composite material with an content of enamel and synthesized Alumina as 1wt%, 3wt% and 5wt%. Experimental investigation has been carried out for the prepared nano composites materials with respect to dielectric parameter measurements such as dielectric loss (tan ${\delta}$), dielectric constant (${\varepsilon}$), dielectric strength under various temperature. The partial discharge level also measured for all the samples and the PD inception voltage is also observed and compared. Weight loss of the material has been analyzed through TGA. It has been experimentally proved that 3wt% of Alumina nano filler added enamel has significant improvement in the dielectric and thermal properties.

• 한국재료학회지
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• 제11권12호
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• pp.1014-1019
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• 2001

The diamond thin film was deposited on Si(100) substrate from$CH_3OH/H_2O$mixtured gas using a hot filament chemical vapor deposition(HFCVD) method. The deposition condition for samples has been varried with the$CH_3OH/H_2O$composition. Scanning electron microscopy(SEM) and Raman spectroscopy has been employed for the sample analysis. The diamond sample has been obtained below 20Pa with$CH_3OH/H_2O$mixtured gas. The crystallinity of diamond film improved as the composition $CH_3OH$decreases from 60Vol% to 52Vol%, and the sample structure changed from the cauliflower to the diamond structure. But the sample structure was becomes cauliflower at 50Vol% of in$CH_3OH$ in the $CH_3OH/H_2O$. It was shown that the$CH_3OH$ has threshold composition.

• Bulletin of the Korean Chemical Society
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• 제29권5호
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• pp.1013-1017
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• 2008

Syndecan-3 is a cell-surface heparan sulfate proteoglycan, which performs a variety of functions during cell adhension process. It is also a coreceptor for growth factor, mediating cell-cell and cell-matrix interaction. Syndecan-3 contains a cytoplasmic domain potentially associated with the cytoskeleton. Syndecan-3 is specifically expressed in neuron cell and has related to neuron cell differentiation and development of actin filament in cell migration. Syndecans each have a unique, central, and variable (V) region in their cytoplasmic domains. And that region of syndecan-3 may modulate the interactions of the conserved C1 regions of the cytoplasmic domains by tyrosine phosphorylation. Cytoplasmic domain of syndecan-3 has been synthesized for NMR structural studies. The solution structure of syndecan-3 cytoplasmic domain has been determined by two-dimensional NMR spectroscopy and simulated-annealing calculation. The cytoplasmic domain of the syndecan proteins has a tendency to form a dimmer conformation with a central cavity, however, that of syndecan-3 demonstrated a monomer conformation with a flexible region near C-terminus. The structural information might add knowledge about the structure-function relationships among syndecan proteins.

• 대한화장품학회지
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• 제42권2호
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• pp.153-162
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• 2016

본 연구에서는 해파리로부터 콜라겐 추출물을 제조하였고, 이에 대한 보습 효과를 측정하였다. 보습 효과는 caspase 14 발현, filaggrin, hyaluronan synthase-3 (HAS- 3), aquaporin-3 (AQP-3) 및 desmocollin (DSC)을 측정하였다. 그 결과, caspase 14 mRNA 발현은 비교물질인 retinoic acid (RA)와 유사한 효과를 나타냈다. 그리고 콜라겐 추출물은 20 mg/mL의 농도에서 각각 211.7%, 139.9%, 212.5% 및 116.8%의 filaggrin, HAS-3, AQP-3 및 DSC 발현 증가를 나타냈다. 따라서, 본 연구에서 해파리 콜라겐 추출물은 보습 효과를 갖는 화장품 소재로서의 개발 가능성이 클 것으로 기대할 수 있다.

• 한국전자파학회논문지
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• 제18권5호
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• pp.539-546
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• 2007

본 논문에서는 온-칩 스파이럴 인덕터 해석에 대한 3차원 전자장 시뮬레이션 방법을 제시하였으며, 이 방법은 정확히 예측 가능한 CMOS VCO를 설계하는데 적용될 수 있음을 보였다. VCO는 CMOS 0.25 um 표준 공정을 이용하여 LC-공진형으로 구현하였으며, 공진기의 스파이럴 인덕터는 실리콘 기판과의 사이에 그라운드 패턴을 삽입한 경우와 그렇지 않은 경우에 대해 각각 VCO를 구현하여 인덕터의 Q값 개선에 의해 VCO의 위상 잡음이 어느 정도 개선되는지를 검증하였다. 제작된 VCO는 2.5 V 제어 전압에서 3.094 GHz, -12.15 dBm 출력을 가지며, LC 공진에 사용된 단일 인덕터의 Q는 그라운드 패턴을 삽입한 경우 3 GHz에서 8% 정도 개선됨을 시뮬레이션을 통해 검증하였으며, 이로 인한 위상 잡음은 3 MHz 오프셋 주파수에서 9 dB 개선되어짐을 실험을 통해 확인하였다.

• 전자통신동향분석
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• 제37권3호
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• pp.64-73
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• 2022

As the COVID-19 pandemic has decreased face-to-face communication in everyday life, our interest in cultural communication via virtual world has grown significantly. In particular, the demand for applications that use three-dimensional (3D) data generation technology such as virtual reality, augmented reality, virtual performances, and realistic content is rapidly increasing in the entertainment and gaming industries. Additionally, improved computing capacity has increased the demand for high-resolution data. This study investigates the trends in 3D scanning and photogrammetry technologies that can support high-quality 3D data generation and introduces the high-resolution 3D data generation technology developed and reported in ETRI.

• 유기물자원화
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• 제13권3호
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• pp.63-70
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• 2005

음식물류폐기물의 직매립 금지로 종량제 봉투에 버려지던 상당량의 음식물류가 제외되면서 도시생활폐기물의 조성은 최근 급변하고 있다. 이에 본 연구에서는 2004년~2005년 2년간 3회에 걸쳐 중소규모의 도시 내 10개 지점에서 배출되는 도시생활폐기물을 발생원에서 수거하여 폐기물의 물리화학적 조성을 조사하고, 이로부터 음식물류폐기물의 직매립 금지조치가 폐기물의 성상변화에 미치는 영향을 정리하였다. 음식물류폐기물의 직매립 금지로 생활폐기물 중의 음식물류의 함량은 2004년도 대비 중량기준으로 약 12% 감소하였으며, 겉보기 밀도도 약 25% 감소하였다. 또한 전체 폐기물 중의 수분함량은 32.3%로 2004년도에 비하여 14.1% 감소하였으며, 폐기물의 저위발열량은 직매립 금지 후 약 32% 증가하여 2991.4 kcal/kg의 값을 나타내었다. 매립폐기물에 의한 매립가스 발생량은 연간 가스발생량 기준으로 최대 5%가 감소되어 매립지에서의 환경오염물질 배출량의 저감효과도 일부 예측되었다.

• Korean Journal of Acupuncture
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• 제21권1호
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• pp.79-93
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• 2004

Objectives and methods : To study on the anti-cancer, anti-metastasis and immune response improvement effects of Herbal-acupuncture with Sinomenii acuti Lignum infusion solution(SAL-HAS), we injected Sinomenii acuti Lignum infusion solution into Joksamni$(ST_{36})$ of C57BL/6 mouse which is corresponding to human Joksamni(ST36). We observed its effect on the number of $CD25^+/CD4^+,\;CD8^+/CD3e^+,\;CD69^+/B220^+,\;NK1.1^+/CD3e^+$ cells in mouse PBMCs(peripheral blood mononuclear cells), the number of the pulmonary colony, and the effect on MST(mean survival time) and ILS(increase in MST over control) of C57BL/6 mice implanted intravenously with B16-F10 melanoma. Results and Conclusions : 1. The spleen cells proliferation of the sample groups treated with SAL-HAS extract has increased significantly compared with that of the control group. 2. The percentage of the $CD25^+/CD4^+,\;CD8^+/CD3e^+,\;CD69^+/B220^+,\;NK1.1^+/CD3e^+$ cells in C57BL/6 mouse PBMCs of the sample groups treated with SAL-HAS has increased compared with that of the control group. 3. The pulmonary colony number of the sample groups SAL-HAS has decreased significantly compared with that of the control group. 4. MST and ILS of the sample groups SAL-HAS have increased significantly compared with those of the control group.

• Nuclear Engineering and Technology
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• 제54권12호
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• pp.4571-4584
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• 2022

The analysis of rapid flow transients in Reactor Coolant Pumps (RCP) is essential for a reactor safety study. An accurate and precise analysis of the RCP coastdown is necessary for the reactor design. The coastdown of RCP affects the coolant temperature and the colloidal crud in the primary coolant. A realistic and kinetic model has been used to investigate the behavior of activated colloidal crud in the primary coolant and steam generator that solves the pump speed analytically. The analytic solution of the non-dimensional flow rate has been determined by the energy ratio β. The kinetic energy of the coolant fluid and the kinetic energy stored in the rotating parts of a pump are two essential parameters in the form of β. Under normal operation, the pump's speed and moment of inertia are constant. However, in a coastdown situation, kinetic damping in the interval has been implemented. A dynamic model ACCP-SMART has been developed for System Integrated Modular and Advanced Reactor (SMART) to investigate the corrosion due to activated colloidal crud. The Fickian diffusion model has been implemented as the reference corrosion model for the constituent component of the primary loop of the SMART reactor. The activated colloidal crud activity in the primary coolant and steam generator of the SMART reactor has been studied for different equilibrium corrosion rates, linear increase in corrosion rate, and dynamic RCP coastdown situation energy ratio b. The coolant specific activity of SMART reactor equilibrium corrosion (4.0 mg s^-1) has been found 9.63×10^-3 µCi cm^-3, 3.53×10^-3 µC cm^-3, 2.39×10^-2 µC cm^-3, 8.10×10^-3 µC cm^-3, 6.77× 10^-3 µC cm^-3, 4.95×10^-4 µC cm^-3, 1.19×10^-3 µC cm^-3, and 7.87×10^-4 µC cm^-3 for ²⁴Na, ⁵⁴Mn, ⁵⁶Mn, ⁵⁹Fe, ⁵⁸Co, ⁶⁰Co, ⁹⁹Mo, and ⁵¹Cr which are 14.95%, 5.48%, 37.08%, 12.57%, 10.51%, 0.77%, 18.50%, and 0.12% respectively. For linear and exponential coastdown with a constant corrosion rate, the total coolant and steam generator activity approaches a higher saturation value than the normal values. The coolant and steam generator activity changes considerably with kinetic corrosion rate, equilibrium corrosion, growth of corrosion rate (ΔC/Δt), and RCP coastdown situations. The effect of the RCP coastdown on the specific activity of the steam generators is smeared by linearly rising corrosion rates, equilibrium corrosion, and rapid coasting down of the RCP. However, the time taken to reach the saturation activity is also influenced by the slope of corrosion rate, coastdown situation, equilibrium corrosion rate, and energy ratio β.