• 정보보호학회논문지
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• 제21권2호
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• pp.131-138
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• 2011

기존의 FPGA기반 DES 전수조사 시스템은 비용대비 높은 성능을 가지고 있으나, 단일 FPGA에서 DES 알고리즘의 최적화 설계에 대한 연구는 미흡하다. 본 논문에서는 77개 Xilinx Virtex5-LX50 FPGA로 구성된 상용 FPGA 클러스터 시스템의 단일 FPGA에 최적화된 하드웨어 DES를 제안한다. 이를 위해서 DES 코어의 파이프라인 수, DES 코어 수, DES 코어의 동작 주파수 등에 따른 설계 공간 탐색을 수행하여 단일 FPGA에 333MHz로 동작하는 16개의 DES 코어를 집적했다. 또한, 각 FPGA에 공급되는 전력의 제한으로 인한 성능 하락을 줄이기 위해서 저전력 설계를 적용하여 333MHz로 동작하는 8개의 DES 코어를 집적했다. 제안된 DES을 상용 시스템에 적용할 경우, 각각 최대 2.03일과 4.06일 안에 DES 키를 찾을 수 있을 것으로 판단된다.

• Advances in materials Research
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• 제12권2호
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• pp.161-177
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• 2023

This paper proposes an analytical method to investigate the free vibration behaviour of new functionally graded (FG) carbon nanotubes reinforced composite beams based on a higher-order shear deformation theory. Cosine functions represent the material gradation and material properties via the thickness. The kinematic relations of the beam are proposed according to trigonometric functions. The equilibrium equations are obtained using the virtual work principle and solved using Navier's method. A comparative evaluation of results against predictions from literature demonstrates the accuracy of the proposed analytical model. Moreover, a detailed parametric analysis checks for the sensitivity of the vibration response of FG nanobeams to nonlocal length scale, strain gradient microstructure-scale, material distribution and geometry.

• Environmental Analysis Health and Toxicology
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• 제6권1_2호
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• pp.39-57
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• 1991

The effect of red ginseng ethanol extract on the immunotoxicity of diethylstilbestrol (DES) was studied in ICR mice. ICR male mice were divided into S groups (10 mice/group), and red ginseng ethanol extract (50, 100 and 200 mg/kg body wt., respectively) and DES (1 mg/kg body wt.) were injected intraperitoneally (i.p.) to ICR mice once a day for 2 weeks. Mice were sensitized and challenged with sheep red blood cells (S-RBC). Immune response were evaluated by humoral immunity, cell-mediated immunity, non-specific immunity, and circulating leukocyte counts. The results of this study were summarized as followings: 1. The DES-treated control group as compared with normal group showed the tendency to decrease body weight rate and relative liver weight, decreased both humoral and cellular immune responses, phagocyte activity, and circulating leukocyte counts, but increased the natural killer (NK) cell activity. 2. Compared with the DES-treated control group, DES plus red ginseng ethanol extract-treated groups significantly decreased the body weight rate (P<0.01). Relative liver weight was significantly decreased in DES plus red ginseng ethanol extract (50mg/kg)-treated group (P<0.01), but significantly increased in DES plus red ginseng ethanol extract (100mg/kg)-treated group (P<0.01). Relative spleen and thymus weights were significantly enhanced in DES plus red ginseng ethanol extract (100 mg/kg)-treated group (P<0.01), but significantly decreased in DES plus red ginseng ethanol extract (200 mg/kg)-treated group (P<0.01). 3. Both humoral and cellular immune responses were significantly decreased in DES plus red ginseng ethanol extract-treated groups rather than in the DES-treated control group (P<0.01). Especially, it weakened the decrease in DES plus red ginseng ethanol extract (100 mg/kg)-treated group. 4. Phagocyte activity and circulating leukocyte counts were significantly decreased in DES plus red ginseng ethanol extract-treated groups rather than in the DES-treated control group (P<0.01). Especially, it weakened the decrease in DES plus red ginseng ethanol extract (100 mg/kg)-treated group. NK cell activity was significantly enhanced in DES plus red ginseng ethanol extract (100 mg/kg)-treated group (P<0.01), but significantly decreased in DES plus red ginseng ethanol extract (50 and 200 mg/kg)-treated groups (P<0.01).

• 한국항공우주학회지
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• 제38권2호
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• pp.99-110
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• 2010

강한 압축성을 갖는 유동의 DES 해석에서, 일반적인 경험상수 $C_{DES}$ 값 0.65를 사용할 경우 경계층 내에서 인위적으로 LES 모드로 수행된다. 본 연구에서는 S-A DES 모델에서 RANS 모드 보호를 위하여 사용되는 난류 길이와 벽거리 비의 분포 함수를 이용한 $C_{DES}$의 동적 결정 방법을 제시하였다. 동적 $C_{DES}$ 결정식을 초음속 기저 유동장에 적용한 결과 다른 모델 상수를 사용한 기존의 연구 결과에 비하여 우수한 예측을 보여주었다.

• 한국정보통신학회논문지
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• 제17권1호
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• pp.41-48
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• 2013

본 논문에서는 개인기반 클라우드 컴퓨팅 환경에서 복잡하고 시간이 많이 소요되는 3DES 알고리즘에 비해 기존의 DES 암호화 알고리즘을 기반으로 안정성과 속도를 개선한 알고리즘을 제안한다. 제안하는 알고리즘은 DES 알고리즘에 있어 안전성 측면에서 단점인 초기치환 및 최종치환을 위한 고정된 치환테이블을 스프레드 랜덤 인터리버 기법을 적용한 동적 치환박스를 적용하여 보안성을 제고하였다. 기존 알고리즘과의 시뮬레이션 결과 비교를 통해 제안하는 알고리즘을 활용할 경우 최소한의 변경으로 전달 데이터에 대한 기밀성과 안정성을 확보하고 빠른 속도로 암호화 및 복호화를 달성할 수 있음을 확인할 수 있었으며 CBC 모드를 적용하여 가변 길이의 데이터에 대해서도 효과적인 암호화가 가능하다.

• Structural Engineering and Mechanics
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• 제80권6호
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• pp.727-736
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• 2021

In this work, mathematical modeling of the passive vibration controls of a three-layered sandwich beam under hard excitation is developed. Kelvin-Voigt Viscoelastic model is considered in the core. The formulation is based on the higher-order zig-zag theories where the normal and shear deformations are taken into account only in the viscoelastic core. The dynamic behaviour of the beam is represented by a complex highly nonlinear ordinary differential equation. The method of multiple scales is adopted to solve the analytical frequency-amplitude relationships in the super-harmonic resonance case. Parametric studies are carried out by using HSDT and first-order deformation theory by considering different geometric and material parameters.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.56-60
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• 2006

We review our studies on the growth of microcrystalline silicon films by the standard PECVD technique. In situ spectroscopic ellipsometry studies allow the optimization of the complex film structure with respect to competing aspects of the growth process. Fine tuning the hydrogen flux, the ion energy, and the nature of the species contributing to deposition produces unique films with a fully crystallized interface with silicon nitride. These materials have been successfully incorporated in bottom gate TFTs which present mobility values in the range of 1 to 3 $cm^2/V.s$, and stable characteristics when submitted to a bias stress. The stability of these TFTs makes them suitable for driver applications in AMLCDs as well as pixel elements in OLED displays.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1025-1028
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• 2005

Microcrystalline Si (${\mu}c-Si$) TFTs were fabricated using a conventional bottom gate amorphous Si (a-Si) process. A unique ${\mu}c-Si$ deposition technique and TFT architecture was proposed to enhance the reliability of the TFTs. This three-mask TFT fabrication process is comparable with existing a-Si TFT procesess. In order to suppress nucleation at the bottom interface of Si, before deposition of the ${\mu}c-Si$ an $N_2$ plasma passivation was conducted. A typical transfer characteristic of the TFTs shows a low off-current with a value of less than 1 pA and a sub threshold slop of 0.7 V/dec. The DC stress was applied to verify the use of ${\mu}c-Si$ TFTs for AMOLED displays. After 10,000 s of application of the stress, the off-current was even lowered and sub-threshold slope variation was less than 5%. For AMOLED displays, OLED pixel simulation was performed. A pixel current of 13 ${\mu}A$ was achieved with $V_{data}$ of 10 V. After the simulation, a linear equation for the pixel current was suggested.

• 복식
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• 제19권
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• pp.175-194
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• 1992

Le Proche-Orient est le pays de la Bible, Le peuple He breu ancien, appartenant la race des S mits s mi-nomades, est venu avec Abraham, de m sopotamie en Palestine, terre de Canaan. Nous avons consid r les v tements du peuple des anciens H breux en nous basant sur la Bible et en observant des peintures murales et des bas-reliefs des divers payes de l'ancienne poque, Pour comprendre l' volution des v tements des gens de la pr sente r gion palestinienne, nous avons tudi les v tements traditionnels de la race b douine qui m nent jusqu' maintenant une vie nomade dans le m nent jusqu' maintenant une vie nomade dans le d sert, parce que nous n'avons pas pu connaitre le processus d' volution des v tements apr s l'ancienne poque la suite d' v nements historiques compliques. En conclusion, nous pouvons nous r sumer comme suit: 1) Nous pensons que la kimlah, costume important du peuple h breu ancien est devenu abajeh, manteau des B douins, puisque ces v tements servent prot ger le corps lors des changments de temps, et la nuit on les utilise comme couverture et comme sac pour y mettre des objets, et comme tente lors su travail. en un mot, les fonctions de la Simlah et celles de l'abajeh sont les memes l' poque ancienne et maintenant. 2) Nous pensons que la forme et l'utilisation de la Kethoneth ayant une forme de tunique et de la thob des B douins sont presque semblable. La kethoneth et la thob sont la tuniqu importante que portent jusqu' maintenant tous les peuples du Proche-Orient. 3) Comme on le voit dans la Bible, les femmes du peuple h breu et celles des B douins utilisent le voile pour couvrir la e te, et se servent d'accessoires pour d corer leur corps. A l'avenir, les vVtements des Palestiniens, dans une recherche pous approfondie, feront l'objet de a 2 me partie de l' tude des costumes du Proche-Orient.

• Coupled systems mechanics
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• 제12권3호
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• pp.199-220
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• 2023

This article presents a new analytical model to study the effect of porosity on the shear correction factors (SCFs) of functionally graded porous beams (FGPB). For this analysis, uneven and logarithmic-uneven porosity functions are adopted to be distributed through the thickness of the FGP beams. Critical to the application of this theory is a determination of the correction factor, which appears as a coefficient in the expression for the transverse shear stress resultant; to compensate for the assumption that the shear strain is uniform through the depth of the cross-section. Using the energy equivalence principle, a general expression is derived from the static SCFs in FGPB. The resulting expression is consistent with the variationally derived results of Reissner's analysis when the latter are reduced from the two-dimensional case (plate) to the one-dimensional one (beam). A convenient algebraic form of the solution is presented and new study cases are given to illustrate the applicability of the present formulation. Numerical results are presented to illustrate the effect of the porosity distribution on the (SCFs) for various FGPBs. Further, the law of changing the mechanical properties of FG beams without porosity and the SCFare numerically validated by comparison with some available results.