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101.
Ki-Whan Song Yong Kyu Lee Jae Sung Sim Hoon Jeoung Jong Duk Lee Byung-Gook Park You Seung Jin Young-Wug Kim 《Electron Devices, IEEE Transactions on》2005,52(8):1845-1850
We have developed an integration technology for the single electron transistor (SET)/CMOS hybrid systems. SET and CMOS transistors can be optimized without any possible degradation due to mixing dissimilar devices by adopting just one extra mask step for the separate gate oxidation (SGOX). We have confirmed that discrete devices show ideal characteristics required for the SET/CMOS hybrid systems. An SET shows obvious Coulomb oscillations with a 200-mV period and CMOS transistors show high voltage gain. Based on the hybrid process, new hybrid circuits, called periodic multiband filters, are proposed and successfully implemented. The new filter is designed to perform a filtering operation according to the periodic multiple blocking bands of which a period is originated from the SET. Such a novel function was implemented efficiently with a few transistors by making full use of the periodic nature of SET characteristics. 相似文献
102.
Sang-Gil Park Hyun-Jin Sim Ji-Hyun Yoon Jae-Eun Jeong Byoung-Jae Choi Jae-Eung Oh 《Journal of Mechanical Science and Technology》2009,23(10):2801-2806
Human hearing is very sensitive to sound, so a subjective index of sound quality is required. Each situation of sound evaluation
is composed of Sound Quality (SQ) metrics. When substituting the level of one frequency band, we could not see the tendency
of substitution at the whole frequency band during SQ evaluation. In this study, the Design of Experiments (DOE) is used to
analyze noise from an automotive Heating, Ventilating, and Air Conditioning (HVAC) system. The frequency domain is divided
into 12 equal parts, and each level of the domain is given an increase or decrease due to the change in frequency band based
on the “loud” and “sharp” sound of the SQ analyzed. By using DOE, the number of tests is effectively reduced by the number
of experiments, and the main result is a solution at each band. SQ in terms of the “loud” and “sharp” sound at each band,
the change in band (increase or decrease in sound pressure) or no change in band will have the most effect on the identifiable
characteristics of SQ. This will enable us to select the objective frequency band. Through the results obtained, the physical
level changes in arbitrary frequency domain sensitivity can be determined. 相似文献
103.
Monolithically integrated grating cavity tunable lasers 总被引:1,自引:0,他引:1
Oh Kee Kwon Jong Hoi Kim Kang Ho Kim Eun Deok Sim Hyun Soo Kim Kwang Ryong Oh 《Photonics Technology Letters, IEEE》2005,17(9):1794-1796
A novel grating cavity tunable laser is proposed and experimentally demonstrated. It is realized by monolithically integrating a semiconductor optical amplifier, a dispersive element, a phase-control section, and an etched diffraction grating in a single chip. Tuning operation is based on electrically controlled beam deflection provided by dispersive element and phase matching by phase-control section. With the electrical control, the wavelength tuning of 8.5 nm with a sidemode suppression ratio of about 35 dB has been successfully achieved. 相似文献
104.
Laura Moss Derek Sleeman Malcolm Sim Malcolm Booth Malcolm Daniel Lyndsay Donaldson Charlotte Gilhooly Martin Hughes John Kinsella 《Knowledge》2010,23(4):309-315
Within the medical domain there are clear expectations as to how a patient should respond to treatments administered. When these responses are not observed it can be challenging for clinicians to understand the anomalous responses. The work reported here describes a tool which can detect anomalous patient responses to treatment and further suggest hypotheses to explain the anomaly. In order to develop this tool, we have undertaken a study to determine how Intensive Care Unit (ICU) clinicians identify anomalous patient responses; we then asked further clinicians to provide potential explanations for such anomalies. The high level reasoning deployed by the clinicians has been captured and generalised to form the procedural component of the ontology-driven tool. An evaluation has shown that the tool successfully reproduced the clinician’s hypotheses in the majority of cases. Finally, the paper concludes by describing planned extensions to this work. 相似文献
105.
106.
M. Anicete-Santos R. C. Lima E. Orhan M. A. M. A. Maurera L. G. P. Simões G. Souza P. S. PIZANI E. R. Leite J. A. Varela E. Longo 《Scientific Modeling and Simulation》2005,12(2-3):111-119
The SrWO4 (SWO) powders were synthesized by the polymeric precursor method and annealed at different temperatures. The SWO structure was obtained by X-ray diffraction and the corresponding photoluminescence (PL) spectra was measured. The PL results reveal that the structural order–disorder degree in the SWO lattice influences in the PL emission intensity. Only the structurally order–disordered samples present broad and intense PL band in the visible range. To understand the origin of this phenomenon, we performed quantum-mechanical calculations with crystalline and order–disordered SWO periodic models. Their electronic structures were analyzed in terms of band structure. The appearance of localized levels in the band gap of the order–disordered structure was evidenced and is a favorable condition for the intense PL to occur. 相似文献
107.
108.
Jorge Laine Joaquin Brito Francisco Severino Germán Castro Patricia Tacconi Simón Yunes José Cruz 《Catalysis Letters》1990,5(1):45-54
The effect of prereduction on CO oxidation activity of unsupported copper-chromite oxide catalysts was examined. Results were found to be in good agreement with two mechanisms for a surface copper enrichment due to CO prereduction which produced an activity increase in the copper-chromite catalyst. 相似文献
109.
Christian L.A. Sze Wey Chua Tian Yeong Sim Ling Xiang Liu 《IEEE transactions on instrumentation and measurement》2001,50(2):259-262
We have measured the hysteresis in output voltage arising from loss of power for three Fluke 732B dc voltage references. Continuously powering the internal temperature-controlled oven provides the best accuracy with such Zener-diode-based dc voltage references. Batteries are used to provide power continuity when shipping between laboratories. We have shown that for these particular instruments, an apparent hysteresis induced by humidity is likely to dominate any hysteresis arising from loss of battery power when transit between laboratories takes three days or more. Our conclusion is that as much, if not more, care needs to be taken when dealing with humidity than with loss of battery power when shipping between laboratories. When the highest accuracy of dc voltage comparison is required, it becomes necessary to apply voltage corrections using the measured values of humidity coefficients and the relative humidity occurring during transit 相似文献
110.