• 한국해양공학회지
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• 제19권2호
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• pp.1-11
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• 2005

In the present paper, the hydrodynamic properties of a Rahmen type flexible porous breakwater with dual fixed pontoon system interacting with obliquely or normally incident small amplitude waves are numerically investigated. This system is composed of dual vertical porous membranes hinged at the side edges of dual fixed pontoons, and a submerged horizontal membrane that both ends are hinged at the steel frames mounted pontoons. The dual vertical membranes are extended downward and hinged at bottom steal frame fixed into seabed. The wave blocking and dissipation mechanism and its effects of permeability, Rahmen type membrane and pontoon geometry, pretensions on membranes, relative dimensionless wave number, and incident wave headings are thoroughly examined.

• 한국컴퓨터산업학회논문지
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• 제3권7호
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• pp.953-956
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• 2002

인터넷 사용 증가로 인한 통신망에 대한 위협은 갈수록 증대되고 있다. 이에 대한 방안으로 많은 보안장비들이 개발되어 설치되고 있으며, 침입차단시스템에 이어 근래에는 침입탐지시스템에 대한 연구와 개발이 활성화되고 있다. 그러나, 네트워크의 규모가 커지고, 관리 대상 시스템의 수가 방대해짐에 따라 현재의 단일 네트워크 단위의 관리로는 해결이 어렵다. 본 논문에서는 IETF에서 진행되고 있는 PBNM(Policy-Based Network Management) 기술을 도입하여 대규모의 네트워크의 보안을 관리하기 위한 통합 침입탐지시스템(Integrated Intrusion Detection System:IIDS)을 설계한다. 통합 침입탐지시스템은 다수의 침입탐지 에이전트로 구성되어 있으며, 시스템의 요구사항과 기능별 요소들에 대하여 기술하고 있다.

• Journal of Astronomy and Space Sciences
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• 제33권3호
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• pp.207-210
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• 2016

Under the assumption of the presence of a medium-scale E × B drift vortex of plasma in the daytime midlatitude F region, and using a simplified ionospheric model, we demonstrate that the E × B drift produces noticeable perturbations in the horizontal distribution of the plasma density in the upper F region. The pattern of ion density perturbations shows two separate medium scale domains of enhanced and reduced ion density with respect to the background. The E × B drift does not produce multiple small-scale ion density irregularities through plasma mixing because of the suppression effect of the field-aligned ambipolar plasma diffusion.

• 한국해안해양공학회지
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• 제5권2호
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• pp.84-90
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• 1993

구형 해저지형과 이안제를 가진 해안에 대한 완경사방정식의 해를 구하는데 반복기법(Conjugate Gradient Method, Panchang et al., 1991)을 사용하였다. 지형 및 구조물로 인한 파랑의 전파변형에 대한 계산결과가 실험치와도 잘 일치하였다. 종내 과도한 기억용량 때문에 광역에는 완경사방정식을 그대로 사용하기가 어려웠지만 이 기법을 사용하면 그런 어려움은 해결된 것으로 판단된다. 특히 소요되는 계산시간이 짧고 복잡한 지형 및 구조물에 대해서도 별 어려움 없이 적용할 수 있는 것이 큰 장점이다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제13권3호
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• pp.57-65
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• 2007

Over the last years several studies have been carried out in the welfare facilities for the elderly in Japan. These have mainly focused on small scale projects, multi-functional houses and on the improvement of specifically designed equipments. This study examines the residents' life patterns and using patterns in group living having various space constitution and, does it for the purpose of looking for the formation of well state places, life patterns and the domains to use spaces for the aged who became independent. I intend to grasp their life patterns by physical space constitution and to show a direction of the house form that they can live in while feeling relieved in areas.

• Genomics & Informatics
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• 제7권1호
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• pp.26-31
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• 2009

Heat shock proteins are a class of molecular chaperones that can be found in nearly all organisms from Bacteria, Archaea and Eukarya domains. Heat shock proteins experience increased transcription during periods of heat induced osmotic stress and are involved in protein disaggregation and refolding as part of a cell's danger signaling cascade. Heat shock protein, Hsp20 is a small molecular chaperone that is approximately 20kDa in weight and is hypothesized to prevent aggregation and denaturation. Hsp20 can be found in several strains of Proteobacteria, which comprises the largest phyla of the Bacteria domain and also contains several medically significant bacterial strains. Genomic analyses were performed to determine a common evolutionary pattern among Hsp20 sequences in Proteobacteria. It was found that Hsp20 shared a common ancestor within and among the five subclasses of Proteobacteria. This is readily apparent from the amount of sequence similarities within and between Hsp20 protein sequences as well as phylogenetic analysis of sequences from proteobacterial and non-proteobacterial species.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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• pp.79-82
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• 1999

Using Small Angle Light Scattering (SALS), the effect of quench depth on the kinetics of phase separation for ternary solution blends was investigated. The system was composed of two polymers (polystyrene and polybutadiene) and a solvent (toluene). The analyses of the early stage of phase separation were based of the Cahn-Hilliard theory [1,5]. Apparent diffusion coefficients and the fastest mode of fluctuations were evaluated, when quench depth of the system were varied near the critical composition of polymer. In the late stage of phase separation, the domain growth showed a power law with the 1/3 exponent, i.e. $q_m(t)~t^{-1/3}$. For comparison between real images and scattering profiles with time, the image of phase domains with time were obtained by using Laser Confocal Scanning Microscopy (LSCM).

• 한국세라믹학회지
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• 제40권11호
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• pp.1047-1057
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• 2003

A sub-nanometer resolution Scanning Nonlinear Dielectric Microscope (SNDM) was developed for observing ferroelectric polarization. We also demonstrate that the resolution of SNDM is higher than that of a conventional piezo-response imaging. Secondly, we report new SNDM technique detecting higher nonlinear dielectric constants $\varepsilon$$\_$3333/ and $\varepsilon$$\_$33333/. Higher order nonlinear dielectric imaging provides higher lateral and depth resolution. Finally, the formation of artificial small inverted domain is reported to demonstrate that SNDM system is very useful as a nano-domain engineering tool. The nano-size domain dots were successfully formed in LiTaO$_3$ single crystal. This means that we can obtain a very high density ferroelectric data storage with the density above 1T-bits/inch$^2$.

• Macromolecular Research
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• 제15권5호
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• pp.396-402
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• 2007

The dielectric properties and various pattern-forming states of dual-frequency material in a nematic phase, as well as its mixture containing low concentrations of reactive monomers, are reported. The dielectric relaxation behaviors of nematic MLC 2048 are presented and compared to its mixture containing both mesogenic and nonmesogenic reactive monomers. The sign-inversion frequency of the dielectric anisotropy was significantly shifted on the addition of small amounts of the reactive monomers. However, all three mixtures used in this study essentially exhibited the same field-induced instabilities at different frequencies and voltage domains of the applied electric field. A broad band of modulated states were found to exist above a critical voltage and within a voltage dependent frequency band in the vicinity of the sign-inversion frequency, $f_I$, of the dielectric anisotropy. As the $f_I$ of the mixtures shifted, so did the bands of the modulated state of the different mixtures and the temperatures, which were well matched with the measured $f_I$ value.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.297-300
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• 2005

This paper presents vibration control of an engine mount for a passenger vehicle utilizing ER fluid and piezoelectric actuator. The proposed engine mount can be isolated the vibration of wide frequency range with many types of amplitude. The main function of ER fluid is to attenuate vibration for low frequency with large amplitude, while the piezoelectric actuator is activated in hish frequency range with small amplitude. A mathematical model of the engine mount is derived using Hydraulic model and mechanical model. After formulating the governing equation of motion, then field-dependent dynamic stiffness of the engine mount is evaluated for various engine speed and excitation amplitude conditions. Then robust controller is designed to attenuate vibration of wide range frequency component. Computer simulation is undertaken in order to evaluate the vibration control performance such as transmissibility magnitude in frequency domains.