• Journal of Institute of Control, Robotics and Systems
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• v.5 no.5
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• pp.600-613
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• 1999

This paper focuses on development of a performance manager for IEEE 802.4 token bus networks to serve large-scale integrated systems. In order to construct the management algorithm, the principles of fuzzy logic, genetic algorithm, and neural network have been combined to represent human knowledge and to imitate of human inference mechanism. Through the simulation experiments, it is shown that the proposed performance manager is capable of improving the network performance without a priori knowledge.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.11a
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• pp.198-200
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• 2001

Grager-Induced colony formation was examined using strains of green alga Scenedemus dimorphus (Turpin) Kutzing. Alga was cultured in a medium with or without filtered water in which Daphnia magna or Moina macrocopa had been reared. Colony formation was obviously promoted in S. dimorphus by exposure to zooplankton filtered water (ZFW), showing in proportion to the volume of zooplankton filtered water in cultured media. The particle volume as well as the number of cells per one colony of S. dimorphus increased between 24 and 48 hours after exposure to ZFW, which were caused by an infochemical released from from Daphnia or Moina probably as a part of defense mechanism against zooplankton grazing.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.417-420
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• 2005

Plants generally produce secondary metabolites in nature as a defense mechanism against pathogenic and insect attack. In this study, we applied several abiotic elicitors in order to enhance growth and ginseng saponin biosynthesis in the hairy roots of P. ginseng. Generally, elicitor treatments were found to inhibit the growth of the hairy roots, although simultaneously enhancing ginseng saponin biosynthesis. The addition of selenium at inoculum time did not significantly affect ginseng saponin biosynthesis. However, when 0.5 mM selenium was added as an elicitor after 21 days of culture, ginseng saponin content and productivity increased to about 1.31 and 1.33 times control levels, respectively. These results suggest that processing time for the generation of ginseng saponin in a hairy root culture can be reduced via the application of an elicitor.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.592-598
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• 1992

For a high bandwidth, accurate end of arm motion control with good disturbance rejection, the, Momentum Management Approach to Motion control (MMAM) is proposed. The MMAM is a kind of position control technique that uses inertial forces, applied at or near the end of arm to achieve, high bandwidth and accuracy in movement and in the face of force disturbances. To prove the concept of MMAM, the, end point, control of a flexible manipulator is considered. For this purpose, a flexible beam is mounted on the x-y table, and the MMAM actuator is attached on the top of the flexible beam. A mathematical model is developed for the flexible, beam being controlled by the, MMAM actuator and slide base DC motor. A system identification method is applied to estimate some system parameters in the, model which can not be determined because of the complexity of the mechanism. For the end point, control of the. flexible beam, the, optimal linear output feedback control is introduced.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.10
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• pp.1583-1589
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• 2001

Metal matrix composites with whisker reinforcements have significant potentials for demanding mechanical applications including defense, aerospace, and automotive industries. Especially metal matrix composites, which are reinforced with aluminum borate whisker, have been used leer the part of piston head in automobile because of good specific strength and wear resistance. In this study, AC4CH-based metal matrix composites with $Al_{18}$B$_{4}$ $O_{33}$ reinforcement have been produced using squeeze casting method, after T6 heat treatment, we evaluated fatigue life property of matrix and MMC composite and investigated fracture mechanism.m.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.1023-1026
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• 2005

지난 몇 년간 DDoS 공격의 기법들은 더욱 복잡해지고 효과적으로 변하였으며, 공격자를 추적하기는 더욱 힘들어지고 있다. 이러한 문제들에 대응하기 위해 다양한 패킷 필터링 기법과 공격자 추적 기법등 많은 연구들이 진행되어 왔다. 하지만 이러한 노력에도 불구하고 DDoS 공격은 여전히 인터넷의 안정성을 위협하는 요소로 작용하고 있다. 따라서 본 논문에서는 이러한 위협에 대응하기 위하여 Active Edge 라우터 기반의 분산 서비스 거부공격대응 기법을 제안하고자 한다. 제안된 방법의 경우 기존의 중간 라우터(intermediate-router)의 오버헤더, 공격경로 재구성에 필요한 오버헤더, 재구성된 공격경로의 부정확성과 같은 기존의 기법들이 지니고 있던 단점들을 보완하고 있다. 또한 제안된 방법의 경우 공격 패킷을 공격대상 네트워크가 아닌 공격자가 위치하고 있는 네트워크에서 제거함으로서 공격패킷의 필터링 효과를 더욱 향상 시켰다.

• Proceedings of the Korean Information Science Society Conference
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• 2010.06d
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• pp.26-29
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• 2010

네트워크 대역폭 소모 위주로 발생했던 DDoS 공격이 최근에는 웹서비스 대상 시스템 부하 유발을 통해 가용성을 떨어뜨리는 응용계층에서의 DDoS 공격 위주로 발생하고 있다. 이러한 DDoS 공격에 대응하기 위해 History, IP 분산도, GRT, Behavior 기반 등 다양한 대응 메커니즘이 연구되고 있지만 연구초기 단계에 머물러 있다. 본 논문에서는 Admission Control 기반 DDoS 공격대응 메커니즘을 제안하고, 시스템 개발을 통해 성능을 검증하였다. 제안된 메커니즘은 지금까지 발생한 모든 응용계층 DDoS 공격유형에 대응 가능하며, 기존 Behavior 기반 대응기법은 오탐지 가능성이 있으나 제안하는 메커니즘은 오탐지가 발생하지 않는 장점이 있어, 상용 환경에 바로 적용할 수 있을 것으로 예상된다.

• Journal of Powder Materials
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• v.22 no.4
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• pp.247-253
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• 2015

The sintering mechanisms of nanoscale copper powders have been investigated. A molecular dynamics (MD) simulation with the embedded-atom method (EAM) was employed for these simulations. The dimensional changes for initial-stage sintering such as characteristic lengths, neck growth, and neck angle were calculated to understand the densification behavior of copper nano-powders. Factors affecting sintering such as the temperature, powder size, and crystalline misalignment between adjacent powders have also been studied. These results could provide information of setting the processing cycles and material designs applicable to nano-powders. In addition, it is expected that MD simulation will be a foundation for the multi-scale modeling in sintering process.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.369-369
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• 2003

Hemocytes in marine bivalves play important immunological roles in discrimination, opsonization and phagocytosis of foreign materials as a defense mechanism. In this study we report the flow cytometric implications to investigate the immune parameters such as the compositional and the functional characteristics of hemocytes isolated from the Manila clams, Ruditapes philippinarum. Heterogeneity of the hemocytic cell population was determined by the forward scatter (FSC) and side scatter (SSC) cytometric profile which showed three populations: granulocytes, hyalinocytes and small agranular cells. In addition, phagocytosis rate was measured after adding fluorescent-labeled particles. The data were initially analysed for two-parameters: FSC and SSC, then the fluorescent (FL 1) frequency distribution histogram of the hemocyte population was subsequently obtained.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.1-8
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• 2011

A unique biophysical membrane which surrounds the milk fat globules is called the milk fat globule membrane (MFGM). Various researches were studied about origin, composition, structure and bioactive components of MFGM. Bioactive protein components of MFGM play an important beneficiary function such as defense mechanism in new born. Among the bioactive lipid components from MFGM phospholipids showed health enhancing functions. The phospholipids also help in the production of certain dairy product from deterioration. MFGM phospholipids also showed antioxidant activity in some dairy products such as butter and ghee produced from milk of buffalo. Based on the beneficial effects, researchers developed MFGM as functional ingredients in various food products. This current review focuses on health enhancing function of MFGM and its components in various dairy products.