• Title/Summary/Keyword: active agents

검색결과 656건 처리시간 0.026초

분산 임칩 탐지 에이전트를 기반으로 한 지능형 침입탐지시스템 설계 (Design of Intelligent Intrusion Detection System Based on Distributed Intrusion Detecting Agents : DABIDS)

  • 이종성;채수환
    • 한국정보처리학회논문지
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    • 제6권5호
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    • pp.1332-1341
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    • 1999
  • Rapid expansion of network and increment of computer system access cause computer security to be an important issue. Hence, the researches in intrusion detection system(IDS)are active to reduce the risk from hackers. Considering IDS, we propose a new IDS model(DABIDS : Distributed Agent Based Intelligent intrusion Detection System) based on distributed intrusion detecting agents. The DABIDS dynamically collects intrusion behavior knowledge from each agents when some doubtable behaviors of users are detected and make new agents codes using intrusion scenario data base, and broadcast the detector codes to the distributed intrusion detecting agent of all node. This DABIDS can efficiently solve the problem to reduce the overhead for training detecting agent for intrusion behavior patterns.

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A study on constructing GIS component repository on web using registration/retrieval agents

  • Jo, Myung-Hee;Jo, Yun-Won;Bu, Ki-Dong
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.949-951
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    • 2003
  • To improve the reusability and interoperability of GIS components, we propose the registration/retrieval agents, which can search the locating of users' frequently used components in not only the GIS domain but also other spatial information technologies such as GPS, ITS, RS and FM. The registration/retrieval agents increase the reusability through the GIS component based development under distributed GIS components environment and enables the rapid setting of application on the web. Moreover, users can understand easily the information of GIS component and have the effective investment, timeliness and reliability while they have less maintenance effort by agent. In order to design and implement this system on web, HTML and ASP (Active Serve Page), and JAVA were used. In addition, the performance of this system was verified through comparing others, which are similar to.

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Natural Modulators of Estrogen Biosynthesis and Function as Chemopreventive Agents

  • Bhat, Krishna P.L.;Pezzuto, John M.
    • Archives of Pharmacal Research
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    • 제24권6호
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    • pp.473-484
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    • 2001
  • There is clearly a need for novel breast cancer chemopreventive agents with enhanced potency and specificity with tittle or no side effects. To this end, several new chemical moieties have been synthesized or isolated from natural sources. In this reviewal we have described some agents currently in use or under development for treatment or prevention of breast cancer, as well as our own strategies for the discovery of natural product modulators of estrogen biosynthesis and function. In particulars bioassay-guided fractionation of active plant extracts is a unique method for identifying agents with novel mechanisms of action, some of which should be useful for prevention of human cancer. Further, with the advent of combinatorial chemistry and high throughput screening, even greater progress may now be expected with natural product leads.

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Enantiomer의 분리에 이용될 수 있는 Chelate Resin의 개발 (제1보) -가교 폴리스티렌 Resin Matrix의 염화메칠화에 있어서의 용매효과- (Development of Optically Active Chelate Resin for Direct Resolution of Enantiomers (I) -Solvent Effects in Chloromethylation of Crosslinked Polystyrene Resin Matrix-)

  • 김길수;전동원;박경혜
    • Journal of Pharmaceutical Investigation
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    • 제18권2호
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    • pp.69-81
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    • 1988
  • We studied on the synthesis of chloromethylated polystyrene as a precursor of optically active polymers for direct resolution of optical isomers. Changing the degree of crosslinking and the kind of crosslinking agents, several polystyrene resin matrices were synthesized. The matrices were chloromethylated with methylal and chlorosulfonic acid as chloromethylating agents. The effects of solvents of various dielectric constants on the chloromethylation were quantitavely examined. We also synthesized chloromethylated polystyrene of macroreticular type that retained large surface area and good physical stability. The differences between the macroreticular type and macroporous type were investigated.

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국내 시판중인 소아용 피부 보습 제품의 분석 및 고찰 (Analysis of Baby Moisturizers Marketing in Korea)

  • 김윤영;서영민;김장현
    • 대한한방소아과학회지
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    • 제22권3호
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    • pp.63-73
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    • 2008
  • Objectives : The purpose of this study is to analyze the baby moisturizers and give information about basis of herbal moisturizer. Methods : We selected 243 goods by searching with keywords as "baby moisturizer" at 6 major web search engines, 12 web shopping malls in Korea. 10 items were evaluated under three evaluation criteria such as type of product, ingredient and function of goods. Results : Study resulted that the most type of moisturizers were lotion type. 80% of the products contained medical agents. Ingredients of medical agents were herbal medicine, aroma oil, vitamin and extract. The moisturizer for atopic dermatitis contained ceramide about half. The ingredient of herbal medicine existed usually as excipients, not as active ingredient. Conclusion : It is necessary to study and develop new products contained herbal medicine as active ingredient based on the oriental medical theory.

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Therapeutic Agents against Bacteria Causing Porcine Pneumonia

  • Lee, Joo-Yong;Lyoo, Young-Soo;Park, Dong-Ki;Jung, Ji-Hyun;Lee, Chul-Hoon;Kim, Min-Kyun;Lim, Yoon-Gho
    • Journal of Microbiology and Biotechnology
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    • 제11권6호
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    • pp.1102-1105
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    • 2001
  • In order to find therapeutic agents for porcine pneumonia, we screened far antibacterial activities of methanol extracts of 81 higher plants against four pathogenic microorganisms of Heamophilus parasuis, Pasteurella multocida, Actinobacillus pleuropneumonia, and Bordetella bronchiseptica, and found the bark of Cinnamomi cortex showed potent activities. Since this was inexpensive, we purified active compounds from it. The structures of the final active fractions were obtained through an activity-guided fractionation and their antibacterial activities are reported here.

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Alginic acid-silica hydrogel coatings for the protection of ssmotic distillation membranes against wet-out by surface-active agents

  • Xu, J.B.;Spittler, D.A.;Bartley, J.P.;Johnson, R.A.
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.354-354
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    • 2006
  • Alginic acid-silica hydrogel films was prepared for testing as protective coating materials for PTFE OD membranes. Unprotected hydrophobic membranes are subject to wet-out when contacted by surface-active agents. Films were characterised using SEM, XRD, DSC, mechanical strength measurements, and water-swelling measurements. In OD trials using coated membranes, no wet-out occurred over the 15 h duration of three consecutive 5 h OD trials using orange oil-water mixtures. In the case of detergent solutions, the coating afforded protection to the membrane for 4-5 h. In a separate trial, no wet-out occurred when the coated side of the membrane was placed in contact with 1.2 wt % orange oil for 72 hours.

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산화환원 화학 종이 단 분자 층으로 화학 흡착된 전극에서의 전기화학적 정류 (Electrochemical Rectification at Electrode Chemically Modified with Redox Active Agents at Monolayer)

  • 이치우;윤정현;오미경
    • 전기화학회지
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    • 제10권1호
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    • pp.43-47
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    • 2007
  • 산화환원 화학 종이 화학적으로 흡착 된 전극에서의 전자 이동 현상은 흡착 화학 종이 전극표면에 흡착 되기 전과는 다르게 흡착 된 산화환원 화학 종의 전자 이동 특성에 전적으로 의존한다. 이러한 전극 표면에서의 전자이동에 관한 기본적인 변화는 전자 이동 현상에 관한 기초 연구를 넘어 전기화학 촉매, 전기화학적 바이오센서, 분자전자공학 등에 유용한 지식이 되고 있다. 본 고에서는 산화환원 화학 종이 자기 조립 막을 형성하여 화학적으로 흡착 된 전극을 사용 할 때 전극/용액 계면에서 관측 되는 전기화학 정류 전류와 전압 사이의 관계에 대한 상관관계를 소개 한다.

미역줄나무의 항암활성에 관한 연구 (Study on the Antitumor Activity of Tripterygium Regelii Sprague)

  • 박완수
    • 동의생리병리학회지
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    • 제19권2호
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    • pp.441-445
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    • 2005
  • Tripterygium regelii has been used as an oriental medicine, especially antiparasitic, anti-inflammatory and detoxifying agents in East asia. During our research to develop new antitumor agents from natural products, MeOH ext. and CH2Cl2 ext. of Tripterygium regelii showed the potent antitumor activity. In order to purify active compounds from Tripterygium regelii, activity-guided fractionation was carried out. Silica gel and RP-18 column chromatography for the active fraction led to the isolation of two compounds and their antitumor activities were studied. Those two compounds didn't show potent antitumor activity against human tumor cell lines. The structure of two compounds were determined by $^1H-NMR$, $^{13}C-NMR$, DEPT, $^1H-^{13}C$ COSY and IR spectrum. Compound I and Compound II were turned out to be Celastrol, and ${\beta}-sitosteryl-3-o-{\beta}-D-glucopyranoside$ respectively.

Synthesis of Water-Soluble Aminoaryloxy-Methylamino Cosubstituted Polyphosphazenes as Carrier Species for Biologically Active Agents

  • 권석기
    • Bulletin of the Korean Chemical Society
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    • 제22권11호
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    • pp.1243-1247
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    • 2001
  • The water-soluble poly(aminoaryloxy-methylamino phosphazene) has been synthesized and investigated as a polymeric carrier species for the covalent attachment of biologically active agents. The cyclic trimeric model systems were utilized for the synthesis of polymeric analogues containing bioactive side groups. The sodium salt of 4-acetamidophenol was first allowed to react with (NPCl2)3 or (NPCl2)n and was then treated with excess methylamine to yield derivatives of type [NP(NHCH3)x(OArNHCOCH3)y]3 or [NP(NHCH3)x(OArNHCOCH3)y]n. The 4-acetamido groups were then hydrolyzed to 4-aminophenoxy units with potassium tert-butoxide. Coupling reactions between amino group and N-acetylglycine was accomplished with the use of dicyclohexylcarbodiimide. Their properties and structural characterization are discussed.