• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 춘계학술대회
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• pp.710-711
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• 2015

최근 사이버 공격이사회, 국가적 위협으로 대두되고 있다. 최근 신종 악성코드에 의한 A.P.T 공격이 사회적으로 큰 혼란을 야기하고 있다. 이에 따라 기업 내에서 방화벽, IPS, VPN 등의 네트워크 보안 시스템의 통합 관리를 목적으로 하는 통합관제시스템(ESM)의 필요성이 제기되었다. 그러나 기존의 ESM의 방식은 외부에서 내부로 유입되는 트래픽만을 모니터링하는 네트워크 기반 공격 탐지기법을 사용하기 때문에, 외부 사이버 공격만을 차단할 수 있다는 한계점을 가지고 있다. 따라서 본 연구는 주요 IT 기반시설의 네트워크, 시스템, 응용 서비스 등으로부터 발생하는 데이터 및 보안 이벤트 간의 연관성을 분석하여 보안 지능을 향상시키는 빅데이터를 활용한 보안로그시스템을 제안한다. 본 연구에서 제안한 빅데이터를 활용한 보안로그시스템을 통해 분산 기반의 저장/처리 기술 적용하고자 한다.본 기술을 적용한 지능형 정보 분석 플랫폼 구성을 통해, 가용성과 확장성을 확보하여 통합적 보안 관제가 가능하도록 한다. 뿐만 아니라 기업 내로의 악성코드 유입, 감염(전파) 그리고 실시간 모니터링이 가능하여 고객 서비스 만족도가 향상되는 파급효과가 기대된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.367-371
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• 1989

As a menas of designing a robust servo system for electrical motor drive system, an iterative learning control method is proposed by employing the structure of the model algorithmic control. A sufficient condition for the convergency is shown, and via simulation for permanent magnet synchronous motor drive system, it is demonstrated 1hat the method yields a 'good performance even in the presence of the external load distrurbances.

• 생약학회지
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• 제37권3호
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• pp.162-168
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• 2006

The isolation and identification of a new xanthone (6-0-palmitolyl-1,6-dihydroxy-5,7-dimethoxyxanthone) along with n-alkanols, fatty acids, 1,6-dihydroxy-5,7-dimethoxyxanthone, 1,7-dihydroxykanthone, betulinic acid, ${\beta}-sitosterol$, methyl 4-hydroxybenzoate, quercetin, and kaempferol from the aerial parts of Hypericum ascyron was reported. The structures were elucidated by spectroscopic methods, mainly NMR and mass spectrometry.

• 생약학회지
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• 제33권4호통권131호
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• pp.267-271
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• 2002

Prunasin and pomolic acid together with a mixture of ursolic and oleanolic acids, (-)-epicatechin and ${\beta}-sitosterol$ glucoside were isolated from the roots of Chaenomeles japonica. Among these compounds, the isolation of pomolic acid and prunasin is the first report from the genus Chaenomeles.

• Natural Product Sciences
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• 제8권1호
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• pp.26-29
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• 2002

The MeOH extract of Sorbus commixta (Rosaceae) exhibited strong DPPH radical scavenging activity, and through activity-guided fractionation two antioxidant compounds were isolated and identified as $catechin-7-O-{\beta}-D-xylopyranoside$ (1) and $catechin-7-O-\;{\beta}-D-apiofuranoside$ (2) by physicochemical and spectrometric methods. To evaluate the antioxidant effect of these compounds, some in vitro tests, such as the DPPH radical scavenging activity test, the superoxide radical scavenging activity test and the lipid peroxidation inhibitory activity test, were performed. Compounds 1 and 2 showed stronger activities than both a-tocopherol and butylated hydroxy anisole (BHA) in each assay.

• Natural Product Sciences
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• 제12권4호
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• pp.193-196
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• 2006

A mixture of cerebrosides (1) and four triterpenoids (2 - 5) have been isolated from the hexane- and EtOAc-soluble fractions of the roots of Synurus deltoides (Ait.) Nakai (Compositae). Triterpenoid structures were determined as lupeol (2), $\beta-amyrin$ (3), $\alpha-amyrin$ (4), and ursolic acid (5). Synurus cerebrosides (1) were characterized as a common long chain base (2S,3S,4R,8E)-2-amino-8-octadecene-1,3,4-triol and fatty acyl chains; palmitic acid, (2R)-2-hydroxybehenic acid, (2R)-2-hydroxytricosanoic acid, (2R)-2-hydroxylignoceric acid, (2R)-2-hydroxypentacosanoic acid, and (2R)-2-hydroxyhexacosanoic acid. The synurus cerebrosides (1) were the first isolation from a natural source.

• Natural Product Sciences
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• 제14권1호
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• pp.47-50
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• 2008

To evaluate the antiallergic effect of the dried root of Astragalus membranaceus Bunge (AM) (Leguminosae), which inhibited the mouse passive cutaneous anaphylaxis (PCA) reaction in a preliminary experiment, its main constituents, astragalosides I and IV, were isolated and their antiallergic effects were investigated. Astragalosides I and IV inhibited the PCA reaction induced by the IgE-antigen complex, and the scratching behaviors induced by compound 48/80. These constituents reduced the protein expressions of $TNF-{\alpha}$ and IL-4 in IgE-induced RBL-2H3 cells. These findings suggest that astragalosides I and IV as well as AM can improve IgE-induced anaphylaxis and scratching behaviors.

• Archives of Pharmacal Research
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• 제27권12호
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• pp.1211-1215
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• 2004

Ten coumarins were isolated from the root of Angelica dahurica by repeated silica gel column chromatography. Their chemical structures were elucidated on the basic of physicochemical and spectroscopic data. Among them, oxypeucedanin hydrate acetonide (7) was isolated for the first time from this plant. Cytotoxicity of coumarins isolated were determined in vitro against L1210, HL-60, K562, and B16F10 tumor cell lines by MTT method. Pangelin (5) and oxypeucedanin hydrate acetonide (7) showed a potent cytotoxic activity with the $IC_{50}$ values of 8.6 to 14.6 ${\mu}g$ /mL against four kinds of tumor cell lines. Other compounds showed the moderate cytotoxic activity or no activity against the tumor cell lines.

• 한국응용곤충학회:학술대회논문집
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• 한국응용곤충학회 2003년도 추계 학술발표회
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• pp.107-107
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• 2003

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 A
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• pp.395-398
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• 1993

This paper proposes an algorithm to find an optimal trajectory for unspecified paths of the tips of two arms of a dual arm robot. The effective handling a specified object of a dual arm robot closely depends on the effective collision avoidance between parts of robot and the object. For time optimal trajectory without collision, a graphical method is applied for a robot with two degree of freedom. The effectiveness of the proposed method is demonstrated by some simulation results.