• Title/Summary/Keyword: DES[2]

검색결과 549건 처리시간 0.028초

하드웨어 암호화 기법의 설계 및 성능분석 (Design and Performance Evaluation of Hardware Cryptography Method)

  • 아재용;고영웅;홍철호;유혁
    • 한국정보과학회논문지:정보통신
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    • 제29권6호
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    • pp.625-634
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    • 2002
  • 암호화는 송수신자 사이에 메시지 전달이 비밀스럽게 이루어 질 수 있도록 보장해주는 기법이다. 이러한 암호화 알고리즘은 높은 계산량을 필요로 하며, 결과적으로 프로세서 자원을 과도하게 사용하는 문제를 가지고 있다. 이러한 문제점을 해결하기 위하여 암호화 알고리즘을 하드웨어 방식으로 구현함으로써 시스템의 부하를 줄여주는 기법이 제시되고 있다. 본 논문에서는 하드웨어 암호화 기법에 대한 설계 및 구현에 대해서 언급하고 있으며, 하드웨어 암호화 알고리즘과 소프트웨어 암호화 알고리즘에 대한 성능을 비교 분석하였다. 실험 결과에서, 계산 복잡도가 낮은 DES 알고리즘은 하드웨어 방식을 적용하여도 높은 입출력 오버헤드에 의해서 성능이 향상되지 않지만, 계산 복잡도가 높은 Triple DES는 하드웨어 방식을 적용하였을 때, 대략 2-4배 성능이 향상됨을 볼 수 있었다.

Application of Living Ionic Polymerizations to the Design of AB-Type Comb-like Copolymers of Various Topologies and Organizations

  • Lanson, David;Ariura, Fumi;Schappacher, Michel;Borsali, Redouane;Deffieux, Alain
    • Macromolecular Research
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    • 제15권2호
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    • pp.173-177
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    • 2007
  • Living anionic and cationic polymerizations have been combined to prepare various types of comb-like copolymers composed of polystyrene (PS) and polyisoprene (PI) blocks, with a precisely controlled architecture. According to the relative placement of these elementary building blocks, combs with randomly distributed PS and PI or with poly(styrene-b-isoprene) diblock branches (I & II, respectively) can be prepared. The reaction procedure initially includes the synthesis of a poly(chloroethylvinyl ether) using living cationic polymerization, which is used as the reactive backbone to successively graft $PS^-Li^+$ and $PI^-Li^+$ or $PI-b-PS^-Li^+$ to obtain structures (I) or (II). The synthesis of Janus-type PS-comb-b-PI-combs (III) initially involves the synthesis of a diblock backbone using living cationic polymerization, which bears two distinct reactive functions having either a protected or activated form. Living $PS^-Li^+$ and $PI^-Li^+$ are then grafted, in two separate steps, onto each of the reactive functions of the backbone, respectively.

Phase-Field Modelling of Zinc Dendrite Growth in ZnAlMg Coatings

  • Mikel Bengoetxea Aristondo;Kais Ammar;Samuel Forest;Vincent Maurel;Houssem Eddine Chaieb;Jean-Michel Mataigne
    • Corrosion Science and Technology
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    • 제23권2호
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    • pp.93-103
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    • 2024
  • In the present work, a phase-field model for dendritic solidification is applied to hot-dip ZnAlMg coatings to elucidate the morphology of zinc dendrites and the solute segregation leading to the formation of eutectics. These aspects define the microstructure that conditions the corrosion resistance and the mechanical behaviour of the coating. Along with modelling phase transformation and solute diffusion, the implemented model is partially coupled with the tracking of crystal orientation in solid grains, thus allowing the effects of surface tension anisotropy to be considered in multi-dendrite simulations. For this purpose, the composition of a hot-dip ZnAlMg coating is assimilated to a dilute pseudo-binary system. 1D and 2D simulations of isothermal solidification are performed in a finite element solver by introducing nuclei as initial conditions. The results are qualitatively consistent with existing analytical solutions for growth velocity and concentration profiles, but the spatial domain of the simulations is limited by the required mesh refinement.

상이한 몰 비율의 LB 공융용매 처리에 따른 BCTMP 섬유 및 수초지 특성의 변화 (Changes of BCTMP Fibers and Handsheets Properties by the Treatment of LB DES at Different Molar Ratios)

  • 최경화;남윤석;이명구;류정용
    • 펄프종이기술
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    • 제48권1호
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    • pp.75-81
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    • 2016
  • This study was conducted to investigate the effects of deep eutectic solvent (DES) treatment on BCTMP fibers and handsheets properties. DES was prepared using lactic acid and betaine (LB), and the molar ratio of these two components mixtures was controlled to 2:1 (LB 2:1) and 5:1 (LB 5:1). As results, 2% of BCTMP pulp (o.d. weight) was extracted when it was treated by LB 5:1 at $50^{\circ}C$ for 12 hours, stirring constantly at 120 rpm. In contrast, lignin was not extracted when BCTMP was mildly treated by the LB DES mixed with 50% of distilled water at the reacting condition of temperature $60^{\circ}C$ for 2 hours using water bath. These results indicate that conditioned water content and adequate reaction time are needed to achieve effective extraction of lignin. It was also found that stiffening of cellulose fiber due to the mild treatment of LB DES to BCTMP fiber leads to the increase of paper bulk without the loss of strength.

CONVERGENCE ANALYSIS OF PERTURBED HEMIVARIATIONAL INEQUALITIES

  • Mansour, Mohamed-Ait;Riahi, Hassan
    • Journal of applied mathematics & informatics
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    • 제14권1_2호
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    • pp.329-341
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    • 2004
  • We consider the rate of convergence for a class of perturbed hemivariational inequalities in reflexive Banach Spaces. Our results can be viewed as an extension and refinement of some previous known results in this area.

독일 의약품법상의 의약품 위험책임 (Gef$\ddot{a}$hrdungshaftung F$\ddot{u}r$ Arzneimittelsch$\ddot{a}$den nach dem deutschen Arzneimittelgesetz)

  • 전경운
    • 의료법학
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    • 제10권1호
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    • pp.363-388
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    • 2009
  • i) Das deutsche Arzneimittelgesetz(AMG) vom 24. 8. 1976 hat neben der Einf$\ddot{u}$hrung des Zulassungsverfahren f$\ddot{u}$r Arzneimittel anstelle des bisherigen Registrieungsverfahrens vor allem auf dem Gebiet des Haftungsrechts eine bedeutende Neuerung gebracht: die Gef$\ddot{a}$hrdungshaftung f$\ddot{u}$r den pharmazeutischen Unternehmer. Gem$\ddot{a}{\ss}$ $\S$84 AMG ist der pharmazeutische Unternehmer zum Schadensersatz verpflichtet. wenn infolge der Anwndung eines Arzneimittels ein Mensch get$\ddot{o}$tet oder K$\ddot{o}$rper oder die Gesundheit eines Menschen nicht unerheblich verletzt wird. Pharmazeutischer Unternehmer ist, wer das Arzneimittel unter seinem Namen in Verkehr bringt. ii) Die Ersatzpflicht des pharmazeutisches Unternehmers besteht jedoch nur in zwei F$\ddot{a}$llen: a) Das Arzneimittel hat bei bestimmungsgemm$\ddot{a}{\ss}$em Gebrauch sch$\ddot{a}$dliche Wirkungen, die $\ddot{u}$ber ein nach den Erkenntnissen der medizinischen Wissenschaft vertretbares Ma$\ss$ hinausgehen($\S$84 Abs. 1 Satz 2 Nr. 1 AMG). b) Der Schaden ist infolge einer nicht den Erkenntnissen der medizinischen Wissenschaft entsprechenden Kennzeichnung, Fachinformarion oder Gebrauchsinformation eingetreten($\S$84 Abs. 1 Satz 2 Nr. 2 AMG). iii) Mit dem 2. Schadensersatzrechts$\ddot{a}$nderungsgesetz ist, dem Konzept von $\S$6 Umwelthaftungsgesetz folgend, eine gesetzliche Kausalit$\ddot{a}$tsvermutung eingef$\ddot{u}$hrt worden. Ist das angewendete Arzneimittel nach den Gegebenheiten des Einzelfalls geeignet, den entstandenen Schaden zu verursachen, so soll vermutet werden, da$\ss$ das Arzneimittel auch den konkreten Schaden beim Anwender verursacht hat($\S$84 II AMG). Der pharmazeutische Unternehmer hat dann diese Vermutung zu wiederlegen. iv) Gem$\ddot{a}{\ss}$ $\S$94 AMG hat der pharmazeutische Unternehmer f$\ddot{a}$r seine Haftpflicht Deckungsvorsorge entweder durch eine Hafpflichtversicherung oder eine Freistellungs- oder Gew$\ddot{a}$hrleistungsverpflichtung eines Inl$\ddot{a}$ndischen Kreditinstituts zu treffen. v) Aber koreanisches Arzneimittelgesetz hat keine Gef$\ddot{a}$hrdungshaftung f$\ddot{u}$r Arzneimittelschaden. Es gibt nur Gefahrdungshaftung des Hersteller aufgrund des Produkthaftungsgesetzes, das auf das Arzneimittel Anwendung findet. Ich glaube, in Zukuft soll koreanisches AMG die Gef$\ddot{a}$hrdungshaftung f$\ddot{u}$r den pharmazeutischen Unternehmer regeln.

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관상동맥 약물 용출 스텐트 삽입 후 항혈소판제제 3제요법과 2제요법의 임상적 효과 비교 (Effect of Triple Compared to Dual Antiplatelet Therapy After Drug-Eluting Stent Implantation in Percutaneous Coronary Intervention)

  • 예경남;김정태;이숙향
    • 한국임상약학회지
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    • 제22권2호
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    • pp.113-122
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    • 2012
  • ACC/AHA/SCAI Guideline recommends for administration dual antiplatelet therapy after drug-eluting stent (DES) to prevent restenosis and stent thrombosis in patients with percutaneous coronary intervention (PCI). Recently triple antiplatelet therapy including cilostazol is known to reduce restenosis and stent thrombosis significantly after DES implantation. However, there is lack of data providing the efficacy of triple antiplatelet therapy. The purpose of this study is to evaluate the clinical effects of the triple therapy after DES implantation compared with the dual therapy. This retrospective study collected data from medical charts of 251 patients who received DES implantation between Jul 2006 and Jun 2008. They received either dual antiplatelet therapy (N = 154 clopidogrel and aspirin; Dual group) or triple antiplatelet therapy (N = 97 cliostazol, clopidogrel and aspirin; Triple group). Major adverse cardiac event rates (MACE, included total death, myocardial infarction, target lesion revascularization) at 12 months, 24 months, stent thrombosis, rates of bleeding complications and adverse drug reactions were compared between these two groups. Compared with the dual group, the triple group had a similar incidence of the MACE rates at 24months (12.3% vs. 12.4%, p = 0.99). There is no difference in overall stent thrombosis between two groups (Dual group 2.6% vs. Triple group 4.1%, p = 0.5). Subgroup analysis showed that diabetic patients got more benefit in reducing MACE rates but, there is no statistical difference. Bleeding complications and adverse drug effects were not different significantly. As compared with dual antiplatelet therapy, triple antiplatelet therapy did not reduce the 12-months, 24-months MACE rates and stent thrombosis. Bleeding complications and adverse drug effects were not different.

Bending analysis of nano-SiO2 reinforced concrete slabs resting on elastic foundation

  • Mohammed, Chatbi;Baghdad, Krour;Mohamed A., Benatta;Zouaoui R., Harrat;Sofiane, Amziane;Mohamed Bachir, Bouiadjra
    • Structural Engineering and Mechanics
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    • 제84권5호
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    • pp.685-697
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    • 2022
  • Nanotechnology has become one of the interesting technique used in material science and engineering. However, it is low used in civil engineering structures. The purpose of the present study is to investigate the static behavior of concrete plates reinforced with silica-nanoparticles. Due to agglomeration effect of silica-nanoparticles in concrete, Voigt's model is used for obtaining the equivalent nano-composite properties. Furthermore, the plate is simulated mathematically with higher order shear deformation theory. For a large use of this study, the concrete plate is assumed resting on a Pasternak elastic foundation, including a shear layer, and Winkler spring interconnected with a Kerr foundation. Using the principle of virtual work, the equilibrium equations are derived and by the mean of Hamilton's principle the energy equations are obtained. Finally, based on Navier's technique, closed-form solutions of simply supported plates have been obtained. Numerical results are presented considering the effect of different parameters such as volume percent of SiO2 nanoparticles, mechanical loads, geometrical parameters, soil medium, on the static behavior of the plate. The most findings of this work indicate that the use of an optimum amount of SiO2 nanoparticles on concretes increases better mechanical behavior. In addition, the elastic foundation has a significant impact on the bending of concrete slabs.

감마선($^{60}Co$) 처리 효과에 의한 억새의 변이체 유기 및 유망 계통 육성 (Promising line development of sweet sorghum by gamma-ray treatment)

  • 이문섭;복태규;최윤표;이희봉
    • 농업과학연구
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    • 제38권1호
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    • pp.7-10
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    • 2011
  • In order to develop the new Miscanthus varieties for biomass, characteristics of collected materials were surveyed. Also, they were treated with S-azide(Sodium-azide) and DES(dethyl sulfate) for promising lines and 0.2% Colchicine for polyploidy, respectively. CNU-J1 line induced with chemical, DES and S-azide treatment showed shorter than others in stem height and stem diameter. CNU-N1 line treated with 10 mM DES showed earlier than non-treated lines in flowering as 7days. Among selected lines, the CNU-J1 line was crossed with DB-1 selected as a superior line and their hybrid was expected to be high in biomass than others. Especially, CNU-W1 line treated with 2.5~5.0 mM DES showed heading in M1 generation.