• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.670-674
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• 2012

The photovoltaic performance of solid-state dye-sensitized solar cells employing hole transport material (HTM), 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenyl-amine)-9,9'-spirobifluorene (spiro-MeOTAD), has been investigated in terms of HTM overlayer thickness. Two important parameters, soak time and spin-coating rate, are varied to control the HTM thickness. Decrease in the period of loading the spiro-MeOTAD solution on $TiO_2$ layer (soak time) leads to decrease in the HTM overlayer thickness, whereas decrease in spin-coating rate increases the HTM overlayer thickness. Photocurrent density and fill factor increase with decreasing the overlayer thickness, whereas open-circuit voltage remains almost unchanged. The improved photocurrent density is mainly ascribed to the enhanced charge transport rate, associated with the improved charge collection efficiency. Among the studied HTM overlayer thicknesses, ca. 230 nm-thick HTM overlayer demonstrates best efficiency of 4.5% at AM 1.5G one sun light intensity.

• Water Engineering Research
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• 제6권1호
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• pp.17-30
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• 2005

The bed evolution of the stretch of the River Rhine between km-812.5 and km-821.5 is characterised by general bed degradation as a result of the river training works and dredging activities of the last two centuries. The degradation of the river bed affects the water levels, and so the navigation conditions. To combat the erosion of the river bed with the aim to keep up the shipping traffic and to avoid the ecological system damages due to water level reductions, sand-gravel-mixtures were added to the river (so called artificial grain feeding activities). This paper presents the results of an application of a graded sediment transport model in order to study morpholodynamical characteristics due to artificial grain feeding activities in the river stretch. The finite element code TELEMAC2D was used for flow calculation by solving the 2D shallow water equation on non-structured grids. The sediment transport module SISYPHE has been developed for graded sediment transport using a multiple layer model. The needs to apply such graded sediment transport approaches to study morphological processes in the domain are discussed. The calculations have been carried out for the case of middle water flow and different size-fraction distributions. The results show that the grain feeding process could be well simulated by the model.

• Journal of applied mathematics & informatics
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• 제11권1_2호
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• pp.215-241
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• 2003

In this paper, solute transport in heterogeneous aquifers using a modified Fokker-Planck equation (MFPE) is investigated. This newly developed mathematical model is characterised with a time-, scale-dependent dispersivity. A two-dimensional finite volume quadrilateral mesh method (FVQMM) based on a quadrilateral background interpolation mesh is developed for analysing the model. The FVQMM transforms the coupled non-linear partial differential equations into a system of differential equations, which is solved using backward differentiation formulae of order one through five in order to advance the solution in time. Three examples are presented to demonstrate the model verification and utility. Henry's classic benchmark problem is used to show that the MFPE captures significant features of transport phenomena in heterogeneous porous media including enhanced transport of salt in the upper layer due to its parameters that represent the dependence of transport processes on scale and time. The time and scale effects are investigated. Numerical results are compared with published results on the some problems.

• 한국전기전자재료학회논문지
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• 제27권10호
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• pp.657-661
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• 2014

When an abnormal condition occurs due to a fault current at a consumer location where electricity is supplied through high-Tc superconducting(HTS) cable, the HTS cable would be damaged if there is no appropriate method to protect it. The fault-current-limiting type HTS cable that is suggested in this study has a structure of transport part and limit part. It conduct a zero impedance transport current at ordinary operations and carry out a fault current limiting at extraordinary operations. To make a perfect this structure, it is essential to investigate electrical properties of transport part that comprise the fault-current-limiting type HTS cable. In this paper, transport part that comprise HTS wire with copper stabilization layer is examined the current transport properties and the stability evaluation.

• 한국해안해양공학회:학술대회논문집
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• 한국해안해양공학회 1995년도 정기학술강연회 발표논문 초록집
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• pp.66-70
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• 1995

The oscillatory boundary layer that develops when surface waves propagate over the sea bottom affects many flow-pendent phenomena in the coastal zone. Examples of such phenomena are wave energy dissipation due to bottom friction and the initiation and transport of sediment (Grant and Madsen 1986). In nature the boundary layer under waves will almost always be turbulent (Nielsen 1992). (omitted)

• 한국멀티미디어학회:학술대회논문집
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• 한국멀티미디어학회 2002년도 춘계학술발표논문집(하)
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• pp.840-843
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• 2002

본 논문에서는 전송계층에서의 안전한 통신을 위한 사실상의 표준으로서 자리를 잡고 있는 Secure Sockets Layer(SSL)와 Transport Layer Security(TLS)의 Handshake 프로토콜 취약성을 평가하기 위한 평가 도구를 제안한다. SSL/TLS Handshake 프로토콜 고유의 취약성과는 달리 구현 제품들에서의 문제점으로 인하여 보안성이 결여될 수 있다. 현재 SSL/TLS를 구현한 제품들이 다양하게 구현되어 있으나 구현과정에서 벤더나 프로그래머에 따라 SSL/TLS Handshake 프로토콜 고유의 취약성들이 다르게 표출될 수 있으므로 본 논문에서는 이들 구현제품들의 문제점으로 인한 보안성 결여를 평가하기 위한 도구를 개발한다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.458-460
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• 2008

Four kinds of copolymers with fluorene and biphenylamine units were synthesized by palladium-catalyzed polycondensation reaction. These polymers were characterized in terms of their UV/Visible and photoluminescence (PL) properties in solution and film state. These polymers were also studied as a hole transporting material in the polymer light emitting diode (PLED) devices.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 컴퓨터소사이어티 추계학술대회논문집
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• pp.251-254
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• 2003

DMB is a next-generation multimedia broadcasting system that not only enables digital broadcasting services such as transmission of CD-duality audio, traffic information, and real-time stock information, but also allows reception of high-quality digital TV in high-speed driving conditions. In the DMB system, MPEG-2 TS(Transport Stream) multiplex method and MPEG-4 System SL(Sync Layer) have been selected as the delivery layer. In this paper, an efficient interface scheme between an MPEG-2 TS processing hardware and software-implemented MPEG-4 system within a DMB terminal device is proposed.

• 한국인쇄학회지
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• 제9권1호
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• pp.1-11
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• 1991

In this reseach, double-layered photoconductor consist of the carrier generation layer(CGL) of $\varepsilon$ type copper phthalocyanine thin film by an aqueous coating method and the carrier transport layer(CGL) of polyvinyl carbazol(PVK) by spin coating. We inverstigated effect of the surfactant solution and cathod electrolysis to the crystal type of $\varepsilon$-CuPc in CGL with TEM, SEM and X- ray diffraction spectroscopy and studied the mechanism of an aqueous coating for the preparation of CGL. The effect of the washing of CGL about the electrophotographic characteristics of the $\varepsilon$-CuPc/PVK doublelayered photoconductors is studied also.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.119.4-119
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• 1998