• 제목/요약/키워드: CPA

검색결과 282건 처리시간 0.032초

하드웨어 DES에 적용한 다중라운드 CPA 분석 (Multi-Round CPA on Hardware DES Implementation)

  • 김민구;한동국;이옥연
    • 전자공학회논문지CI
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    • 제49권3호
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    • pp.74-80
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    • 2012
  • 최근 Nakatsu는 전력파형의 정보가 충분하지 못한 환경에서 분석 성능을 향상 시키는 하드웨어 AES(Advanced Encryption Standard)에 대한 다중 라운드 CPA (Correlation Power Analysis, CPA) 분석기법을 제안하였다. 본 논문에서는 하드웨어로 구현된 DES(Data Encryption Algorithm)에 1라운드와 2 라운드를 분석하여 마스터키를 찾아내는 다중 라운드 CPA 분석 방법을 제안한다. 제안된 다중 라운드 CPA 분석 기법은 DPA Contest에서 제공한 하드웨어 DES 암호 알고리즘의 전력파형을 사용하여 시뮬레이션을 하였다. 그 결과 300개의 전력파형의 정보만으로도 마스터키의 모든 정보를 찾을 수 있었다. 또한 단일라운드 CPA 분석 기법보다 다중라운드 CPA 기법이 더 효과적으로 마스터키를 분석하는 것을 검증하였다.

의약품의 용출에 관한 연구(제 17보)-데옥시콜린산나트륨에 분산된 클로르프로파미드의 용출 특성- (Studies on Dissolution Rate of Drugs (XVII)-Dissolution Characteristics of Chlorpropamide Dispersed in Sodium Deoxycholate-)

  • 문기주;서성훈;김수억
    • Journal of Pharmaceutical Investigation
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    • 제19권3호
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    • pp.155-161
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    • 1989
  • Coprecipitates of chlorpropamide (CPA)-sodium deoxycholate (DC-Na) were prepared at various ratios of CPA to the DC-Na. The X-ray diffraction and DSC measurements indicated that CPA in 1:1 and 1:3 w/w CPA-DC-Na coprecipitates did not exist in amorphous form, but the others were amorphous. The dissolution rate of CPA from the CPA-DC-Na coprecipitates increased in distilled water and KP V 2nd disintegration test fluid (pH 6.8), but decreased extremely in KP V 1st disintegration test fluid (pH 1.2). The dissolution rates of CPA-DC-Na coprecipitates were compared with those of CPA alone and CPA-DC-Na physical mixtures. Especially, it was found that the dissolution rate of CPA markedly increased in the case of 1:5 CPA-DC-Na coprecipitate. The concentration of CPA dissolved from CPA-DC-Na coprecipitate reached a plateau within 5-10 min, and thereafter gradually decreased, indicating that CPA released from the coprecipitate was recrystallized.

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방위각 CPA를 이용한 수중표적의 CPA 거리와 속도의 비 추정 (Estimating The Ratio of The CPA Distance to Velocity for Underwater Target using Bearing CPA)

  • 김정훈;윤경식;서익수;이균경
    • 전자공학회논문지
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    • 제53권6호
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    • pp.146-151
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    • 2016
  • 본 논문에서는 등속 직선 기동하는 수중표적의 CPA 상황에서의 방위각 정보를 이용하여 표적의 CPA 거리와 속도의 비를 추정하는 기법을 제시한다. 선행 연구를 통해 근접센서를 이용한 포락선 CPA 기법으로 이 값을 추정하는 방안이 제시되었으나, 이는 표적과 수신 센서의 거리가 가깝거나 다중경로로 인한 간섭효과가 커질 경우 성능이 떨어지는 문제를 가진다. 이에 이를 극복하는 방안으로 표적 방위각 정보를 이용하는 방위각 CPA 기법을 제시한다.

토양중(土壤中) p-Chlorophenoxy Acetic Acid(CPA)의 잔류평가(殘留評價) (On the Persistency of p-Chlorophenoxy Acetic Acid(CPA) in Soil)

  • 박창규;김용환
    • Applied Biological Chemistry
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    • 제24권2호
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    • pp.145-148
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    • 1981
  • A study has been conducted to ascertain persistency of p-chlorophenoxy acetic acid (CPA), a plant growth substance, in soil. CPA was extracted from soil and then converted to a gIc (ECD) sensitive derivative, 2-chloroethyl p-chlorophenoxy acetate (CPA ester) with $BCI_3$ as catalyst. Total recovery of CPA including the chemical conversion was 49.4% and detection limit of CPA in soil, a minimum concentration of the compound which can be identified on chromatogram, was 0.03 ppm. Half life of CPA in clay loam under field conditions was 20 days and that of CPA under laboratory condition was 27.4 days respectively.

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CPA분석을 이용한 기동하는 수신기에서의 표적 속도 추정기법 (Target Velocity Estimation Technique Using CPA Analysis at the Moving Receiver)

  • 이수형;김정수;이균경
    • 한국음향학회지
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    • 제28권4호
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    • pp.336-342
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    • 2009
  • 일정한 주파수의 음향신호를 발생시키는 표적이 기동할 때 한 개의 고정된 센서에서 관측된 신호의 주파수는 시간에 따라 도플러 변이가 발생한다. 이러한 도플러 변이 현상을 이용한 기존의 CPA (Closest Point of Approach) 분석으로 센서 수신기에 표적이 최단거리로 근접했을 때의 시간, 거리, 속력 그리고 실제 신호의 중심주파수를 추정할 수 있다. 본 논문에서는 고정된 단일 센서 대신에 일정한 속도로 기동하는 배열센서 수신기에서 주파수뿐만 아니라 표적의 방위각을 관측하여 이로부터 표적의 실제 기동속도를 추정하는 기법을 제안한다. 그리고 제안한 기법의 성능검증을 위해 오차 분석 및 모의 실험을 수행하였다.

Isolation and characterization of 4-chlorophenoxyacetic acid-degrading bacteria from agricultural soils

  • Chung, Min-Jae;Shin, Se-Young;Park, Yong-Keun;Min, Kyung-Hee;Ka, Jong-Ok
    • Journal of Microbiology
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    • 제35권2호
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    • pp.117-122
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    • 1997
  • Several dominant 4-CPA-degrading bacteria were isoalted from agricultural soils. Most of the isolates were identified as Burkholderia species by fatty acid methyl ester (FAME) analysis, but they were idstinct in chromosomal patterns obtained by PCR amplification of repetitive extragenic palindromic (REP) sequences. These strains were generally restricted in their substrate utilization capabilities. The 4-CPA degradative enzymes were idnducible by 4-CPA and some isolates appeared to mineralize 4-CPA via formation of 4-chlorophenol and 4-chlorocatechol as intermediates during its biodegradation pathway. Plasmid DNAs were not detected from most of the isoaltes and their 4-CPA genes wer on the chromosomal DAN. The 4-CPA degradation patterns in axenic cultures and natural soils varied depending on the strains and soils. The inoculation of 4-CPA degraders much improved the removal of 4-CPA from the 4-CPA treated soils.

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ebXML CPP/CPA 문서 편집기 설계 및 구현 (Design and Implementation of an ebXML CPP/CPA Editor)

  • Moonyoung Chun;Soo-Young Oh;HyeonSung Cho;Hyun-Kyu Cho
    • 한국전자거래학회:학술대회논문집
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    • 한국전자거래학회 2001년도 International Conference CALS/EC KOREA
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    • pp.241-251
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    • 2001
  • B2C e-commerce is now sufficiently stable. Judging from its success, we can expect B2B to similarly improve business processes for a better return on investment. To achieve B2B e-commerce, many consortia have been trying to develop a B2B framework. As a result, the ebXML is started as an international standard for B2B e- commerce based on XML. The exchange of information between two parties requires each party to know the other party's supported business collaborations, the other party's role in the business collaboration, and the technology details about how the other party sends and receive messages. In some cases, it is necessary for the two parties to reach agreement on some of the details. The ebXML CPP and CPA specification defines how to describe these. In this paper, we'll describe our design and implementation of an ebXML CPP and CPA editor which enables each party to create and edit his profiles and which automatically composites two CPPs. Although it is possible to create and edit CPP and CPA documents with general-purpose XML editor, it is not easy to create and edit CPP and CPA documents with a general-purpose XML editor. Moreover, the detailed procedures for CPA formation from CPPs are currently not provided in the specification. Therefore, we propose two approaches for a CPA formation in addition to easy-to-use user interface.

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결빙억제제의 종류, 농도 및 침지시간이 참전복 Haliotis discus hannai 발생배의 생존활성에 미치는 영향 (Effects of Concentration and Immersion Time of Three Cryoprotective Agents on the Embryos Development of Abalone Haliotis discus hannai)

  • 정종균;임한규;손맹현;김종현;정민환;장영진
    • 한국발생생물학회지:발생과생식
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    • 제15권4호
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    • pp.301-308
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    • 2011
  • 결빙억제제(CPA)의 종류, 농도 및 침지시간이 참전복 Haliotis discus hannai 발생배의 생존활성에 미치는 영향을 조사하였다. 4세포, 담륜자 및 피면자를 dimethyl sulfoxide, ethylene glycol, propylene glycol 농도별로 10분, 20분 및 30분간 침지하였다. CPA 침지 후 각 발생배의 발생진행률은 각 CPA 농도가 낮을수록, CPA 침지시간이 짧을수록 높았다. 또한, 피면자에서 비틀림전까지의 발생진행률은 4세포에서 담륜자까지의 것보다 높았다. CPA 침지 후 발생진행률 및 유생활성지수는 ethylene glycol에서 가장 높았다. 참전복 발생배의 냉동보존 효과를 높일 수 있는 CPA 및 농도는 ethylene glycol 2.0 M, 평형시간은 30분인 것으로 추정된다.

흑효모유래 $\beta$-glucan의 패혈증 치료효과 및 항돌연변이 활성 평가 (Anti-mutagenic and Anti-septic Effects of $\beta$-glucan from Aureobasidium pullulans SM-2001)

  • 구세광
    • 한국한의학연구원논문집
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    • 제15권3호
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    • pp.75-82
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    • 2009
  • Anti-mutagenic and anti-septic effects of $\beta$-1,3/1,6-glucan from Aureobasidium pullulans SM-2001 were evaluated on the on the cyclophosphamide (CPA)-cecal ligation puncture (CLP) and CPA-treated mice. To induce immunosuppression and mutagenicity, 150 and 110 mg/kg of CPA were single intraperitoneally injected at 3 or 1 day before CLP or initial $\beta$-glucan administration. In CLP animals, the cecum was mobilized and ligated below the ileocecal valve, punctured through both surfaces twice with a 22-gauge needle. 125 mg/kg of $\beta$-glucan were dissolved in saline and subcutaneously or orally administered in a volume of 10 ml/kg (of body weight), 4 times, 12 hrs intervals from 6 hrs after CLP or 1 day after second dose of CPA. After treatment of $\beta$-glucan, the mortalities were observed in CPA-CLP model, and the appearance of a micronucleus is used as an index for genotoxic potential in CPA model. As results of CPA-CLP sepsis, all animals (9/9, 100%) in CPA-CLP control were dead within 2 days after CLP. In addition, increase of the number of bone marrow MNPCEs indicated mutagenicity were also observed by treatment of CPA. However, $\beta$-glucan treatment effectively inhibited the mortalities in CPA-CLP, and it also reduced the CPA treatment-related mutagenicity, respectively. These results indicated that $\beta$-glucan has effective anti-septic and anti-mutagenic effects and can be used as an agents for treating sepsis and mutagenicity related to high-dose chemotherapy or radiotherapy. However, further studies should be conducted to observe more detail action mechanisms of it's anti-septic and anti-mutagenic effects.

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Alpha-alkylcysteines as Inhibitors for Carboxypeptidase A. Synthesis, Evaluation, and Implication for Inhibitor Design Strategy

  • Lee, Hyun-Soo;Kim, Dong-H.
    • Bulletin of the Korean Chemical Society
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    • 제23권4호
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    • pp.593-597
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    • 2002
  • (R,S)- and (R)-2-Benzylcysteine (1) and (R,S)-2-phenethylcysteine (2) were synthesized and evaluated as inhibitors for carboxypeptidase A (CPA) with the expectation that these compounds exhibit improved inhibitory activities over 2-benzyl-3-mercaptopropanoic acid (BMPA), a potent CPA competitive inhibitor, possibly having additional interactions of their amino group with the carboxylate of Glu-270 of the enzyme upon binding to CPA. Contrary to the expectation, however, the CPA inhibitory potencies of these compounds were found to be much reduced compared with that of BMPA, suggesting that the amino group in the inhibitors rather exerts steric hindrance in binding of these inhibitors to CPA.