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991.
Cadmium‐Free InP/ZnSeS/ZnS Heterostructure‐Based Quantum Dot Light‐Emitting Diodes with a ZnMgO Electron Transport Layer and a Brightness of Over 10 000 cd m−2 下载免费PDF全文
992.
Hyun?Seok?HongEmail author Jun?Woong?Kim Sang?Jin?Jung Chong?Ook?Park 《Journal of Electroceramics》2005,15(2):151-157
Practical small-sized thick film CO2 sensor with self-heater was fabricated with Na β -Alumina (NBA), Na2Ti6O13-TiO2, and Na2CO3 as a solid electrolyte, reference electrode, and a sensing electrode, respectively. The measured EMF from the sensor followed the Nernstian behavior with CO2 concentration change in the range of 400 to 600∘C (350–580 mW power consumption). However, in the aspect of stability, densification of the NBA thick film and prevention of Na2CO3 evaporation were needed. In this study, an Al2O3 porous layer deposited on Na2CO3 was effective in improving the durability during operation of the sensor. It is thought that Al2O3 suppresses evaporation of Na2CO3. 相似文献
993.
Yu-Dong Bae Byung-Kwon Kang Byeonghoon Park Sang-Moon Lee Young Hyun Kim Hong-Kwon Kim Mun-Kue Park In Kim Jang D.-H. 《IEEE journal of selected topics in quantum electronics》2005,11(1):135-140
Semicooled operation at 40/spl deg/C of electroabsorptive modulator integrated laser (EML) for intermediate reach communication has been demonstrated. Reproducible operation at the elevated temperature was achieved through a device parameter optimized based on the temperature dependence of the dc characteristics of EML and a design of multi-quantum-well structure providing both relevant output power and high-frequency bandwidth at 40/spl deg/C. Good eye pattern and near zero chirp with the average power over 0 dBm are obtained at 40/spl deg/C, with an estimated lifetime over 20 years. 相似文献
994.
Magnetic Resonance Materials in Physics, Biology and Medicine - This study aims to compare an electrocardiogram (ECG)-gated four-dimensional (4D) phase-contrast (PC) magnetic resonance imaging... 相似文献
995.
Jae‐Won Yang Hyun‐Lark Do 《International Journal of Circuit Theory and Applications》2014,42(6):620-631
A soft‐switching high step‐up DC‐DC converter with a single magnetic component is presented in this paper. The proposed converter can provide high voltage gain with a relatively low turn ratio of a transformer. Voltage doubler structure is selected for the output stage. Due to this structure, the voltage gain can be increased, and the voltage stresses of output diodes are clamped as the output voltage. Moreover, the output diode currents are controlled by a leakage inductance of a transformer, and the reverse‐recovery loss of the output diodes is significantly reduced. Two power switches in the proposed converter can operate with soft‐switching due to the reflected secondary current. The voltages across the power switches are confined to the clamping capacitor voltage. Steady‐state analysis, simulation, and experimental results for the proposed converter are presented to validate the feasibility and the performance of the proposed converter. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
996.
Taking the effects of transmission network into account, strategic forward contracting induced by the interaction of generation firms’ strategies in the spot and forward markets is investigated. A two-stage game model is proposed to describe generation firms’ strategic forward contracting and spot market competition. In the spot market, generation firms behave strategically by submitting bids at their nodes in a form of linear supply function (LSF) and there are arbitrageurs who buy and resell power at different nodes where price differences exceed the costs of transmission. The owner of the grid is assumed to ration limited transmission line capacity to maximize the value of the transmission services in the spot market. The Cournot-type competition is assumed for the strategic forward contract market. This two-stage model is formulated as an equilibrium problem with equilibrium constraints (EPEC); in which each firm's optimization problem in the forward market is a mathematical program with equilibrium constraints (MPEC) and parameter-dependent spot market equilibrium as the inner problem. A nonlinear complementarity method is employed to solve this EPEC model. 相似文献
997.
Sang Su Kim Jun-Ki Chung Mun Heum Park Jong Kuk Kim Jae-Yong Kim Won-Jeong Kim 《Journal of Electroceramics》2006,17(2-4):151-155
The Bi3.4La0.6Ti3O12 (BLT) thin film and powder have been prepared by a sol-gel method with annealing at 700°C. Randomly oriented BLT thin film exhibits a large remanent polarization, 2P r = 72 μC/cm2, with a dc applied field strength of 320 kV/cm. Structure of sol-gel derived BLT powder has been investigated by neutron scatterings, and refined by a Rietveld method resulting a reasonable goodness of fit (wR p = 6.7%, and R p = 5.7%) using an orthorhombic (B2cb, a = 5.4221 Å, b = 5.4032 Å, and c = 32.8361 Å). Two different TiO6 octahedra exhibit different polarization directions; (100) from Ti(1)O6, and (011) from Ti(2)O6, which explains the observed large 2P r of the randomly oriented BLT thin film. 相似文献
998.
Porous carbon materials (SM-C, HS-C and TM-C) were prepared using commercial colloidal silicas (SM-30, HS-40 and TM-50) and
a resorcinol-formaldehyde resin as a removable template and a carbon precursor, respectively. All of the prepared carbons
had high surface areas with narrow pore size distributions. In particular, the pore diameter of the carbons could be controlled
over a range of mesopore size by the use of an appropriate silica employed as a template. Mesoporous carbon templated using
TM-50 had the largest pore size, while that for SM-C, was the smallest. Pt nanoparticles were supported on these mesoporous
carbons for use as a catalyst in a polymer electrolyte membrane fuel cell (PEMFC). The crystallite size of the Pt catalyst
was found to be closely related to the properties of the corresponding carbon support. A carbon support with a large pore
size and a high surface roughness was found to favor the dispersion of Pt crystallite. In a single cell test, the Pt catalysts
supported on mesoporous carbons exhibited higher cell performance than that on activated carbon. In particular, the Pt/TM-C
catalyst showed the best cell performance among the catalysts tested. In addition to the high surface area of the active metal,
the large pore size of the Pt/TM-C appears to have positive effect on the distribution of ionomer, resulting in facile formation
of a triple-phase boundary. 相似文献
999.
Young-uk Chung Dong-Ho Cho 《Intelligent Transportation Systems, IEEE Transactions on》2006,7(2):147-155
Code division multiple access (CDMA)-based radio-on-fiber road-vehicle communication systems were proposed to support real-time streaming services in intelligent transportation systems (ITSs). Soft handoff should be provided for real-time streaming services because these services are required to guarantee real-time property and quality of service (QoS). However, soft handoff of real-time streaming services causes the shortage of resource in view of the system. In this paper, the double-adjustment soft-handoff (DASH) scheme is proposed to support seamless service regardless of the shortage of resource and maximize the resource efficiency when real-time streaming services are served in CDMA-based ITSs. The DASH scheme adjusts the data rate of a call when it starts and finishes soft handoff. The performance of the DASH scheme is evaluated by analytical and simulation methods. Performances are evaluated with respect to the blocking probability, the handoff failure probability, and the carried traffic. Numerical results show that the proposed scheme can give relative good maintenance of calls and good throughput. 相似文献
1000.
Wooyoung Kim Pil Kim Ji Bong Joo Hyun Khil Shin Kwang S. Jung Jongheop Yi 《Journal of Electroceramics》2006,17(2-4):679-682
Porous carbon materials with a cylindrical pore structure were prepared using ordered mesoporous silica as a removable template.
To investigate the effect of the structural and textural properties of the products on hydrogen adsorption capacity, different
carbon precursors and synthetic methods were used in their preparation. All of the carbon materials prepared showed a well-defined
pore structure with a high surface area irrespective of the carbon precursor used in the preparation. Hydrogen adsorption
tests indicated that the capacity of the materials for hydrogen adsorption was highly dependent on total surface area and
the pore structure. Based on the N2 sorption results, the total surface area was directly correlated with the hydrogen adsorption capacity. 相似文献