• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.235-235
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• 2010

The Anti-reflection coating(ARC) properties can be formed on silicon substrate using a simple electrochemical etching technique. This etching step can be improve solar cell efficiency for a solar cell manufacturing process. This paper is based on the removal of silicon atoms from the surface a layer of porous silicon(PSi). Porous silicon is form by anodization and can be obtained in an electrolyte with hydrofluoric. It have demonstrated the feasibility of a very efficient porous Si layer, prepared by a simple, cost effective, electrochemical etching method. We expect our research can results approaching to lower than 10% of reflectance by optimization of process parametaer.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.369-372
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• 2002

This paper presents a family of continuous conduction mode with constant-switching pulse width modulator controllers. Unified implementation of quasi steady state approach for various DC-DC converters topoiogies is illustrated. The property and control low for quasi-state approach will be discussed in this paper. The different procedures will be discussed in details with different results for five commonly used DC-DC converters. Both trailing and leading edge pulse width modulation are used. Leading edge modulation can some times lead to simpler control circuitry as will be demonstrated in some circuits. These controllers do not require the multiplier in the voltage feed back loop, error amplifier in the current loop and rectified line voltage sensor, which are needed by traditional control methods. Controller examples and design arc analyzed.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.28-33
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• 2001

Using liquid media of Bacillus licheniformis, extraction with butanol and fractionation with n-hexane and ethyl acetate(EtOAc) were performed, From the EtOAc fraction, the isolation was also performed using chromatography. Three isoflavonoids were isolated from the liquid media of Bacillus licheniformis and identified as diadzein, genistein and genistin by Mass and NMR spectroscopic analysis.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2010.06a
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• pp.67-68
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• 2010

위치 기반 서비스(LBS)는 유비쿼터스(Ubiquitous) 시대에 필요한 핵심 엔진으로 그 중요성이 논의되어 왔다. LBS 시스템은 GPS 뿐만 아니라 휴대폰을 통한 고속 인터넷 접속을 사용하여 사용자의 위치 추적과 같은 기술이 현재 서비스된다. 그러나 소프트웨어 측면에서 대부분의 위치 기반 서비스는 서비스 제공자 위주의 일부 특정 상황을 가정한 서비스 모델 또는 사전에 정의된 일정 지역과 한정된 상황에서의 상황 인식(Context Aware) 서비스 제공이 대부분이다. 그러나 이러한 방법론들은 현실 적용이 어려운 문제점이 제기되고 있다. 본 연구에서는, 사용자들의 상환인식을 통하여 사용자의 특성 지식과 공간지리 선호도 지식 정보 추론을 통한 Geo-Ontology통합시스템을 제시한다. 본 연구에서는 Geo-Ontology통합시스템 중에서 사용자의 상황인지기반 LBS시스템을 제시한다. 사용자들의 개인적인 특성 지식과 공간지리 선호도 지식을 구축할 수 있으며, 이러한 특성으로 구축된 지식 기반 하에 입력된 사용자 정보와 추론을 통하여 사용자의 현재 상황에 대한 가장 적절한 추천 결과가 도출되는 프로토타입 시스템을 제공 할 수 있음을 보였다.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.234-240
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• 2000

The Energy is the basis for almost all industrial activities and domestic needs. But recently there are increasing concerns internationally over environmental problems and consequent climate changes caused by the excessive use of fossil fuels. Furthermore the price of crude oil is increasing steadily with unstable supplies. In order to solve these national energy problems, the utilization of Ocean Energy is introduced as one of the best alternative technologies for the future. OTEC Power Plant has been installed at the West Inchon Power Plant Site. Temperature differences of $20{\sim}25^{\circ}C$ have been utilized for plant operations, where R22 is used as a working fluid. The system is composed of low pressure turbine, plate type heat exchanger, and pumps. In the present investigation the experimental results, such as gross power, net power and objective function, are analysed when temperature differences change from the reference design point.

• Clinical and Experimental Pediatrics
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• v.49 no.8
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• pp.898-901
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• 2006

Constrictive pericarditis represents a rare cause of protein-losing enteropathy in children. Reported is an 11-year-old girl with protein-losing enteropathy (PLE) as the principal manifestations of constrictive pericarditis. After total pericardiectomy, symptoms and signs of PLE disappeared. Doppler echocardiography including tissue Doppler imaging is a useful noninvasive initial diagnostic tool for differential diagnosis of diastolic heart failure.

• IEMEK Journal of Embedded Systems and Applications
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• v.8 no.4
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• pp.195-204
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• 2013

The embedded software has been developed in the forms of various versions that provides similar service based on product family. For increase usefulness of product family, software must has well-structured and reusable properties. Software architecture is important to improve adaptability in model-based development of embedded software mounted onto product family. In this paper, we proposed a technique of ADD(Attribute-Driven Design)-based software architecture design for low power software development. This technique provides a chance to consider the power consumption issue in design phase of software, and makes possible to develop low power embedded software.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1621-1626
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• 2000

A simplified modeling approach for occupied car seats was demonstrated to be feasible. The model, consisting of interconnected masses, springs and dampers, was initially broken down into subsystems and experiments conducted to determine approximate values for model parameters. A short study of the effect of changing model parameters on natural frequencies, mode shapes and resonance locations in frequency response functions was given, highlighting the influence of particular model parameters on features in the mannequin's vibration response. Good agreement between experimental and simulation frequency response estimates was obtained. Future work should include optimization of parameter estimates, the inclusion of viscoelastic and nonlinear elements in addition to the linear springs and dampers, and finally extensions to a 3D model.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.44-51
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• 2000

The reactivity of a range of volatile organic compounds with differing functional groups observed over 0.5% $Pt/{\gamma}-Al_2O_3$ catalyst. In general, the reactivity pattern observed was alcohols > aromatics > ketones > cycloalkane > alkanes. The deep conversion was increased as reaction temperature was increased. A correlation was found between the reactivity of the individual and the strength of the weakest C-Hbond in structure. The conversion of volatile organic compounds increases in order methanol > benzene > cyclohexane > MEK > n-hexane. That is the effect of differences in total dissociation energy. An apparent zeroth-order kinetics with respect to inlet concentration have been observed. A simple multicomponent model based on two-stage redox model made reasonably good predictions of conversion over the range of parameters studied. thus, the catalytic process was suggested as the new VOCs control technology.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.9
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• pp.1381-1387
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• 1989

For the fabrication of ohmic contact to p-type GaAs, In Liquid Metal Ions were implanted into p-type GaAs (Zn:1.5x10**19/cm**3). After the samples were processed by Infrared rapid thermal annealing (IRTA0 or Furance Annealing (FA), I-V and specific contact contact resistivity were measured. Specific contact resistivity was found to be 1.7x10**-5 \ulcorner-cm\ulcornerin IRTA 750\ulcorner, 10 sec annealed sample. The surface characteristics of the samples were investigated with SEM, RHEED, AES. From these results we can know that implanted In ions were formed mixing layer of InAs at the surface.