• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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• pp.706-708
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• 1999

In recent years, analog to digital converter is significant component in high frame rate system. But, in the future. as long as minimum line width is reduced, matching between speed and resolution may be worse. In this paper, first-order $\Sigma-\Delta$ analog to digital converter is adopted and designed as its solutions. Hspice simulation is performed, using $0.65{\mu}m$ CMOS 2-poly 2-metal model parameter.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
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• pp.325-328
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• 2000

The control of the data retention time is a main issue for realizing future high density dynamic random access memory. In this paper, we propose the new implantation scheme by gate-related ion beam shadowing effect and buffer-enhanced $\Delta$ Rp increase using buffered N- implantation with tilt and 4X-rotation that is designed on the basis of the local-field-enhancement model of the tail component. We report an excellent tail improvement of the retention time distribution attributed to the reduction of electric field across the cell junction due to the redistribution of N- concentration which is intentionally caused by Ion Beam Shadowing and Buffering Effect using tilt implantation with 4X-rotation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.591-596
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• 2001

Micron-size mechanical devices are becoming more prevalent, both in commercial applications and in scientific inquiry. Within the last decade, a dramatic increase in research activities has taken place, mostly due to the rapidly expanding growth of applications in areas of MEMS(Micro-Electro-Mechanical Systems), bioengineering, chemical systems, and advanced energy systems. In this study, we have described the effects of vortex viscosity variation on the flowfields in a micro-slot between rotating surfaces of revolution using a micropolar fluid theory. In order to solve this problem, we have used boundary layer equations and applied non-zero values of the microrotation vector on the wall. The results are compared with the corresponding flow problems for Newtonian fluid. Results show that the coefficient $\delta$ controls the main part of velocity ${\upsilon}_x$ and the coefficient M controls the main part of microrotation component ${\Omega}_{\theta}$.

• 한국기계가공학회지
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• 제8권4호
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• pp.90-96
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• 2009

The loading condition of actual construction works is complex. The shear effect of mixed-mode load component are crack propagation mechanism in step larger than the crack initial mechanism. Therefore, in this study received a mixed-mode loading on fatigue crack stress ratio on crack propagation path and speed of progress to learn whether stress affects crack propagation. ${\Delta}$ P a constant state of fatigue tests in Mode I, II give the same stress ratio, frequency 10Hz, sinusoidal waveform was used. A lower stress ratio fatigue crack propagation angle is small. This is less affected by the Mode II. Therefore, a mixed-mode fatigue crack propagation is to progress by the Mode. Stress ratio in a mixed mode crack in the path of progress and found a lot of impact.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2020년도 하계학술대회
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• pp.546-549
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• 2020

본 논문에서는 최신 비디오 코딩 기술에서 잔차(Residual)신호 변환을 효율적으로 수행하기 위한 부동기저(Basis)를 사용하는 방법을 제안한다. 기존의 DCT-II 나 DST-VII 과 같은 고정 기저를 사용하는 방법은 대부분의 잔차신호들에 대해 효과적으로 비상관화(decorrelation)를 수행하지만 복잡한 잔차 신호일수록 성능이 떨어지는 문제가 있었다. 이러한 압축 성능하락 문제를 줄이기 위하여 PCA(Principle Component Analysis) 방법 중 하나인 KLT(Karhunen-Loeve Transform)를 이용하여 부동(floating) 변환 기저를 유도하는 방법을 제안한다. 기존의 KLT 를 이용한 변환 커널 유도 방법들의 문제점인 부호화기 및 복호화기 계산 복잡도를 줄이기 위하여 KL 커널을 분해가능한(Separable) 2 개의 1 차원 커널로 유도하는 방법을 제안하고, 원본 잔차신호와 유사한 텍스처를 찾아 커널을 예측하는 과정을 간소화하는 방법을 제안한다. 제안하는 방법은 HEVC 에서 실험되었으며 정지영상 코딩 Main-Profile 에서 평균 1.4%가량의 BD-PSNR(Bjontegaard Delta-Peak Signal to Noise Ratio) 성능 향상을 보였으며 특히 스크린 컨텐츠 영상에서 최대 4.5%의 성능 향상을 보인다.

• BMB Reports
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• 제48권1호
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• pp.36-41
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• 2015

Recently, we demonstrated that human serum amyloid P component (SAP) specifically recognizes exposed bacterial peptidoglycan (PGN) of wall teichoic acid (WTA)-deficient Staphylococcus aureus ${\Delta}$tagO mutant cells and then induces complement-independent phagocytosis. In our preliminary experiments, we found the existence of human serum immunoglobulins that recognize S. aureus PGN (anti-PGNIgGs), which may be involved in complement-dependent opsonophagocytosis against infected S. aureus cells. We assumed that purified serum anti-PGN-IgGs and S. aureus ${\Delta}$tagO mutant cells are good tools to study the molecular mechanism of anti-PGN-IgG-mediated phagocytosis. Therefore, we tried to identify the intracellular molecule(s) that is involved in the anti-PGN-IgG-mediated phagocytosis using purified human serum anti-PGN-IgGs and different S. aureus mutant cells. Here, we show that anti-PGN-IgG-mediated phagocytosis in phorbol myristate acetate-treated U937 cells is mediated by $Ca^{2+}$ release from intracellular $Ca^{2+}$ stores and anti-PGN-IgGdependent $Ca^{2+}$ mobilization is controlled via a phospholipase C${\gamma}$-2-mediated pathway.

• 한국전기전자재료학회논문지
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• 제18권4호
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• pp.285-296
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• 2005

Reduced pressure chemical vapor deposition technology has been used to study SiGe heterostructure epitaxy and device issues, including SiGe relaxed buffers, proper control of Ge component and crystalline defects, two dimensional delta doping, and their influence on electrical properties of devices. From experiments, 2D profiles of B and P presented FWHM of 5 nm and 20 nm, respectively, and doses in 5×10/sup 11/ ∼ 3×10/sup 14/ ㎝/sup -2/ range. The results could be employed to fabricate SiGe/Si heterostructure field effect transistors with both Schottky contact and MOS structure for gate electrodes. I-V characteristics of 2D P-doped HFETs revealed normal behavior except the detrimental effect of crystalline defects created at SiGe/Si interfaces due to stress relaxation. On the contrary, sharp B-doping technology resulted in significant improvement in DC performance by 20-30 ％ in transconductance and short channel effect of SiGe HMOS. High peak concentration and mobility in 2D-doped SiGe heterostructures accompanied by remarkable improvements of electrical property illustrate feasible use for nano-sale FETs and integrated circuits for radio frequency wireless communication in particular.

• 한국식품영양과학회지
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• 제42권7호
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• pp.1079-1085
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• 2013

본 연구에서는 오미자 농축액 첨가량(0~5%)에 따른 소스의 품질특성과 혈당강하능 및 관능적 특성에 미치는 영향에 대해 조사하였다. 오미자 농축액 첨가량이 증가할수록 수분함량, 총 페놀함량 및 환원당은 증가하였고 pH는 감소하였다. 소스의 이화학 시험 결과 당도, 환원당, 총 페놀함량, ${\alpha}$-amylase 저해율 및 ${\alpha}$-glucosidase 저해율 등은 오미자 농축액의 첨가량에 따라 증가하였다. 소스의 색도는 오미자 농축액 첨가량이 증가함에 따라 명도는 감소하였고, 적색도, 황색도 및 ${\Delta}E$ 값은 증가하였다. 관능적 특성은 소스만 섭취 하였을 때 4% 첨가한 오미자 소스에서 가장 높은 기호도를 나타내었고, 닭 가슴살과 함께 섭취하였을 때 5% 첨가한 오미자 소스의 기호도가 가장 높았다.

• 한국의류산업학회지
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• 제13권6호
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• pp.972-982
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• 2011

The purpose of this study is to improve the method of color developing with alkali solution as a promotor of color developing for feasible use. Cotton fabric was dyed with persimmon extract ranged with 0~3% alkali component with 5 types of strong to mild alkali solution. Heat treatment for color developing was applied to fabric dyed with persimmon extract and alkali mixing solution. Tests were carried out to analyze the change of surface color, ${\Delta},Ea^*b^*$, and water repellent of the dyed cotton fabric. The alkali mixing sample showed higher ${\Delta},Ea^*b^*$ value than control one without alkali mixing on the base of dyed fabric due to high color developing by alkali in the initial step of dyeing process. As alkali concentration increased, deeper dark color appeared on the fabric. The fabric color was changed to more dark in the application of sodium hydroxide, sodium carbonate, potassium carbonate in the initial step of dyeing process but color was not changed by increased heating time. However, the fabric showed a slight dark color with sodium acetate and more color change than that of the fabric dyed with persimmon extract without alkali. Therefore, sodium acetate seemed to a suitable promotor for color developing in persimmon extract dyeing. Property of water repellent was showed after color developing by heating with low concentration of alkali treatment.

• 한국통신학회논문지
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• 제27권8B호
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• pp.796-801
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• 2002

CL1(closed loop mode 1)은 3GPP WCDMA가 규정한 폐루프(closed loop) 송신 다이버시티 기술 중의 하나로서, 기지국에 설치된 2개의 송신 안테나를 통해 방사되는 신호들의 위상을 적절히 조절하여 가입자 단말기의 입력단에 나타나는 신호의 전력을 최대화하고자 하는 방식이다. 이 방식의 핵심 요소는 서로 다른 송신 안테나를 거쳐 가입자 수신기에 도달하는 수신 신호간의 위상 차이 정보를 가입자 단말기가 부호화하여 기지국에 전달하는 것이다. 본 논문에서는 적응 델타 변조(adaptive delta modulation) 방식으로 위상 차이 정보를 표현하여 전달하는 새로운 방안을 제안하고, 이를 기존의 CL1 방식에서 사용하는 위상 차이 표현 방안과 비교한다. 컴퓨터 실험 결과, 페이딩(fading) 특성이 비교적 천천히 변하는 환경에서, 제안한 방식이 CL1의 경우보다 위상 차이를 좀 더 정확하게 표현할 수 있으며, 이로 인해 궁극적으로 더 낮은 BER을 확보할 수 있음을 확인하였다.