• 대한기계학회논문집B
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• 제24권7호
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• pp.945-956
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• 2000

The axisymmetric bodies considered in this study have hemispherical and ellipsoidal noses. The near-field pressure fluctuations over each nose model at $Re_D=2.43{\times}10^5$ were investigated in the laminar separation region and developing turbulent boundary layers using a 1/8' pin-holed microphone sensor. The wall pressure fluctuations were also measured in an axisymmetric boundary layer on a cylinder parallel to mean flow at a momentum thickness Reynolds number of 850 and a boundary layer thickness to cylinder radius ratio of 1.88.

• Clinics in Shoulder and Elbow
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• 제23권4호
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• pp.198-202
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• 2020

Simple clavicle fractures can achieve satisfactory results through conservative treatment, and the less frequency of nonunion. Non-union or malunion can occur in displaced clavicle fractures or comminuted shaft fractures. Treatment of displaced comminuted clavicle shaft fractures is performed by holding together the free fragments with interfragmentary screws or wires and fixing them to the clavicle with a plate. Therefore, we performed interfragmentary fixation using open reduction and internal fixation with bioresorbable screws (Mg-Ca alloy, Resomet bioresorbable bone screw; U&I Corp.) and bioresorbable wires (Mg-Ca alloy, Resomet bioresorbable K-wire and pin, U&I Corp.) for displaced comminuted clavicle fractures (Robinson type 2B) and additionally used a metal plate. We expected decreased irritation and infection due to absorption after surgery. We report four cases that were treated in this way.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2003년도 International Symposium
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• pp.109-119
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• 2003

o In order to start SIP Project .Marketing (& ASIC team) should present biz planning, schedule, device/SIP specs., in SIP TFT prior to request SIP development for package development project. .In order to prevent (PCB) revision, test, burn-in, & quality strategy should be fixed by SIP TFT (PE/Test, QA) prior to request for PKG development. .Target product price/cost, package/ test cost should be delivered and reviewed. o Minimum Information for PCB Design, Package Size, and Cost .(Required) package form factor: size, height, type (BGA, QFP), Pin count/pitch .(Estimated) each die size including scribe lane .(Estimated) pad inform. : count, pitch, configuration(in-line/staggered), (open) size .(Estimated) each device (I/O & Core) power (especially for DRAM embedded SIP) .SIP Block diagram, and net-list using excel sheet format o Why is the initial evaluation important\ulcorner .The higher logic power resulted in spec. over of DRAM Tjmax. This caused business drop longrightarrow Thermal simulation of some SIP product is essential in the beginning stage of SIP business planning (or design) stage. (i.e., DRAM embedded SIP) .When SIP is developed using discrete packages, the I/O driver Capa. of each device may be so high for SIP. Since I/O driver capa. was optimized to discrete package and set board environment, this resulted in severe noise problem in SIP. longrightarrow In this case, the electrical performance of product (including PKG) should have been considered (simulated) in the beginning stage of business planning (or design).

• 마이크로전자및패키징학회지
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• 제17권4호
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• pp.27-33
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• 2010

We have successfully demonstrated a high-pin-count and thin embedded-LSI package to realize next generation's mobile terminals. The following three design key points were applied: (i) Using Cu posts, (ii) Using the coreless structure, (iii) Using a Cu plate as the ground plane. In order to quantitatively determine the contribution of the three points, the five-stage process for reducing the number of metal layers is described by means of the electrical simulation. The point-(i) and (ii) are effective from the viewpoint of the power integrity (PI); that is, these points play important roles in reducing the number of metal layers, and especially the point-(ii) contributes at least twice as the point-(i). The point-(iii) is not effective in the PI, but has a few effects on the signal integrity (SI). For reducing the number of metal layers, we should, at first, pay attention whether the PI characteristics fulfill the specification, and then we should confirm the SI characteristics.

• Journal of Communications and Networks
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• 제11권6호
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• pp.538-543
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• 2009

A wiretap channel I is one of the channel models that was proved to achieve unconditional security. However, it has been an open problem in realizing such a channel model in a practical network environment. The paper is committed to solve the open problem by introducing a novel approach for building wiretap channel I in which the eavesdropper sees a binary symmetric channel (BSC) with error probability p while themain channel is error free. By taking advantage of the feedback and low density parity check (LDPC) codes, our scheme adds randomness to the feedback signals from the destination for keeping an eavesdropper ignorant; on the other hand, redundancy is added and encoded by the LDPC codes such that a legitimate receiver can correctly receive and decode the signals. With the proposed approach, unconditionallysecure communication can be achieved through interactive communications, in which the legitimate partner can realize the secret information transmission without a pre-shared secret key even if the eavesdropper has better channel from the beginning.

• 한국전자파학회논문지
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• 제14권7호
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• pp.734-740
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• 2003

본 논문에서는 4개의 다이오드 감쇠기, 비대칭 커플드 라인 커플러, 대칭 커플드 라인 커플러 및 전력 합성기를 이용한 벡터 모듈레이터형 광대역 아날로그 위상변위기를 구현하였다. 가격, 회로의 크기 및 수동소자의 수에 그 장점이 있는 간단한 구조를 제안하였다. P-I-N 다이오드 감쇠기의 감쇠량에 따른 위상변화를 수식적으로 표현하여, 전체회로를 최적화하였다. 제작된 위상변위기는 1 GHz~3 GHz주파수 대역에서 360$^{\circ}$위상변화를 나타내며, $\pm$8.2$^{\circ}$의 최대 위상 오차 및 16$\pm$2.5 dB의 삽입 손실을 나타내었다.

• 융합보안논문지
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• 제10권4호
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• pp.1-11
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• 2010

최근 인터넷을 통해 개인정보 유출사례가 빈번히 발생하고 있으며, 한번 유출된 개인정보는 회수 변경이 어렵고, 명의도용 사기 등 제3의 범죄로 까지 이어지고 있어 국가차원의 대책 마련이 요구된다. 현재 각 포털사(社) 쇼핑몰 등 인터넷 사업자는 회원 가입시 개인정보를 무분별하게 수집하고 있으며 제대로 된 보안관리가 이루어지지 않고 있는 실정이다. 이러한 상황은 시간이 지날수록 해커가 공격할 수 있는 취약 요인의 수만 증가 시킬 뿐이며 보안 관리 범위도 통제할 수 없게 된다. 또한 국내 외 해커들은 금전적 이득을 얻기 위해 개인정보를 선호하고 있어 향후에도 개인정보 유출 사고는 지속 증가할 것으로 예상된다. 이에 본 논문에서 인터넷 회원가입을 위해 수집하는 개인정보 보안 관리 실태를 살펴보고 유출된 개인정보를 인터넷에서 재사용할 수 없도록 하는 공인인증서 기반 개인 인증체계 개선 모델을 제안하기로 한다.

• Preventive Nutrition and Food Science
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• 제18권2호
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• pp.133-138
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• 2013

This study was performed to compare the quality and functionality of broccoli juice as affected by extraction method. Broccoli juice was extracted using method I (NUC Kuvings silent juicer), method II (NUC centrifugal juicer), and method III (NUC mixer), and the quality properties of the broccoli juices were analyzed using three different methods. Additionally, the antioxidative, anticancer, and anti-hyperglycemic activities of broccoli juice prepared by the three different methods were investigated in vitro. The broccoli juice made by method I contained the highest polyphenol and flavonoid contents at 1,226.24 mg/L and 1,018.32 mg/L, respectively. Particularly, broccoli juice prepared by method I showed higher DPPH and ABTS radical scavenging activities than those of the other samples. Additionally, broccoli juice made by method I showed the highest growth inhibitory effects against HeLa, A549, AGS, and HT-29 cancer cells. Broccoli juice prepared by method I had the highest ${\alpha}$-glucosidase inhibitory effects. These results indicate that there are important differences in chemical and functional qualities between juice extraction techniques.

• 한국산학기술학회논문지
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• 제11권9호
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• pp.3517-3523
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• 2010

본 논문은 이중 에너지 DR(Digital Radiography) 방식 중, 단일 조사 X-선(single shot X-ray exposure) 장치와 이중 모드 검출기 모듈 (Low Energy Detector & High Energy Detector)을 이용한 이중 X-선 이미징이 가능한 검출기 모듈에 관한 연구이다. 상용 BIS(baggage inspection system)에서 사용되고 있는 X-선 발생장치의 스펙트럼과 이중 모드 검출기에 대한 특징 및 방사선적 특성을 분석하여 새롭게 제안 할 검출기 모듈의 최적 설계 방향을 기술하고 상용화된 용화된 LED 및 HED 검출기와 새롭게 제안 한 검출기 모듈에 대해 전기적, 광학적, 방사선적 특성 실험을 실시하여, 새롭게 제안된 검출기 모듈이 BIS 용도로 사용 가능함을 증명하였다. 새롭게 제안 된 검출기 모듈이 적용된 BIS에 대해, 기본 특성 실험에 대한 X-선 영상을 획득하여 실험 및 분석을 실시하였다.

• Journal of Yeungnam Medical Science
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• 제3권1호
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• pp.209-213
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• 1986

소아만성B형간염 환아 24명에게 항virus제인 ribavirin을 15mg/kg/day로 14일간 경구투여한 군과 투여하지 않은 대조군으로 나누어 12개월간 혈청 HBsAg과 HBeAg을 추적 검사한 결과 두군 모두에서 HBsAg과 HBeAg의 감소를 볼 수 없었으므로 ribavirin의 소아만성B형간염에 대한 치료효과는 없는것으로 보여진다. 또한 ribavirin 치료에 따른 특별한 부작용도 볼 수 없었다.