• Structural Engineering and Mechanics
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• 제5권5호
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• pp.565-576
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• 1997

The material-based homogenization design method generates arbitrary topologies of initial structural design as well as reinforcement structural design by controlling the amount of material available. However, if a small volume constraint is specified in the design of Lightweight structures, thin and slender structures are usually obtained. For these structures stability becomes one of the most important requirements. Thus, to prevent overall buckling (that is, to increase stability), the objective of the design is to maximize the buckling load of a structure. In this paper, the buckling analysis is restricted to the linear buckling behavior of a structure. The global stability requirement is defined as a stiffness constraint, and determined by solving the eigenvalue problem. The optimality conditions to update the design variables are derived based on the sequential convex approximation method and the dual method. Illustrated examples are presented to validate the feasibility of this method in the design of structures.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.189-192
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• 2008

A 5.8-inch wide-QQVGA flexible full-color active-matrix OLED display was fabricated on a plastic substrate. Low-voltage-operation organic TFTs and high-efficiency phosphorescent OLEDs were used as the backplane and emissive pixels, respectively. The fabricated display clearly showed color moving images when the driving voltage was below 15 V.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.886-889
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• 2006

Twin Auxiliary Electrodes were applied to the counter sustain electrode structure plasma display panels for the improvement of luminous efficiency. In advanced, we investigated the spatiotemporal behaviors of excited $Xe^{\ast\ast}(2p)$ atoms in that structure unit cell with various applied voltage conditions for the auxiliary electrodes. The near-IR emissions were observed by an ICCD camera combined with narrow band pass filter. As a partial result, the intensity of IR emissions and the response time were improved with the proposed twin auxiliary electrodes.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.235-238
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• 2006

Interface formation between $12CaO{\cdot}7Al_2O_3(C12A7:e^-)$ and Alq3 was investigated using in-situ ultra-violet photoelectron spectroscopy (UPS) and X-ray photoelectron spectroscopy (XPS). The work function and vacuum level shift of $C12A7:e^-$ were change by different surface treatment from 2.6eV to 4.2eV. Also vacuum level shift $(\Delta)$ at the interface were from +0.3eV to -0.3eV.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.401-406
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• 2003

New planar discharge structured AC-PDP has been developed by using TFCS (Thick Film Ceramic Sheet) technology. By applying TFCS to AC-PDP, a sustaining electrode and scanning electrodes are embedded in the TFCS. It is shown that panel performances such as electrical and optical characteristics are superior to commercialized coplanar AC-PDP as well as cost reduction. Moreover the experimental result shows panel performances can be improved drastically by continuous development.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.694-699
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• 1989

This paper presents a technique for an autonomous mobile robot to locate its own position in a visual way. The developed mobile robot perceives its surroundings through an equipped TV camera and acquires the visual information necessary for its next behavior. The robot which is assumed to move in a laboratory environment identifies its position by recognizing three different marks in the environment and analyzing the positional relation between these marks and itself. This technique was examined by an experiment and a satisfactory result was obtained.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.987-990
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• 2002

Fine grayscale data exceeding 8 bits per pixel is mapped into the sRGB color space so as to be displayed on a 24-bit sRGB CRT monitor. The characteristics of the pseudo gray generated by mapping are investigated in terms of the CIELAB color difference and chromaticities.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.1316-1319
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• 2002

In this paper, an online SNR estimator is derived for turbo coded multicode DS/SS systems in Nakagami fading channels. The multicode DS/SS approach is one of promising solutions to obtain higher-rate data transmission in DS/SS technologies. Turbo coding has paid much attention because of the significant improvements on error rate performances in various communication systems including multicode DS/SS systems. However, in the turbo decoding, channel state information, especially signal-to-noise ratio (SNR) at the correlator outputs, is desired in order to obtain such improvements. We evaluate the accuracy of the derived SNR estimation. It is shown that the bit error rate performance using our SNR estimation is close to the performance with perfect knowledge of channel state information.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.188-192
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• 2001

Magnetic separation and sulphidization-flotation for recovery of nickel and copper from two types of scraped condenser wastes, containing 8- l4% nickel and 2-4% copper, were studied. The effects of magnetic field intensities, classification, and grinding on the recovery of nickel and copper were investigated. According to the characteristics of nickel and copper in the scraps, classification-magnetic separation, different magnetic field intensities, and stages-grinding-cleaning of rough concentrate were investigated. The nickel concentrates containing 38-65% nickel with 84-97% recoveries and the copper concentrates containing 25-43% nickel with 35-60% recoveries were obtained by classification-magnetic separation. In addition, copper concentrates containing 26-45% copper with 76-88% recoveries were obtained by sulphidization-flotation from magnetic tailings and middling products.

• Natural Product Sciences
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• 제3권1호
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• pp.49-54
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• 1997

We studied the attachment-repelling activity of flavonoids, stilbenes, and their glycosides against the blue mussel Mytilus edulis galloprouincialis. Molecular mechanics calculations have shown that the most stable conformations of potent repellents 29 and 32 were the same. On the basis of these results, structure-activity relationships of these compounds are discussed.