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11.
MacDonald Angus W. III; Goghari Vina M.; Hicks Brian M.; Flory Janine D.; Carter Cameron S.; Manuck Stephen B. 《Canadian Metallurgical Quarterly》2005,19(6):814
Convergent and divergent validity are critically important in developing psychological measures that reveal interpretable deficits in disordered populations. This article reports on 2 studies that evaluated the validity of context processing measures. In Experiment 1, a confirmatory factor analysis of data from 481 healthy adults established the convergent validity of 2 context processing measures and showed that context processing accounted for significant amounts of variance in standard IQ and working memory measures. In Experiment 2, 20 schizophrenia patients, 16 of their healthy siblings, and 28 controls were evaluated using a novel, short context processing measure, the dot pattern expectancy (DPX) task. The DPX was sensitive to specific deficits in schizophrenia patients and their healthy siblings. These findings support the construct validity of context processing measures, suggest context processing is a component of intellectual functioning, and demonstrate that brief context processing measures remain sensitive to psychopathological deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
12.
Computers in police cruisers 总被引:1,自引:0,他引:1
A typical police cruiser is filled with electronic devices, displays, and inputs, all competing for the officer's attention. The Project54 system integrates those devices, and its speech-based user interface lets officers operate them without taking their eyes off the road. 相似文献
13.
Bashirullah R. Wentai Liu Cavin R. III Edwards D. 《Solid-State Circuits, IEEE Journal of》2006,41(2):461-473
This paper describes an adaptive bandwidth bus (ABB) architecture based on hybrid current/voltage mode repeaters for long global RC interconnect static busses that achieves high-data rates while minimizing the static power dissipation associated with current-mode signaling. Attaining a maximum aggregate bandwidth of 16 Gb/s (i.e., 1 Gb/s per line) across lossy on-chip interconnects spanning 1.75 cm in length, the bus core fabricated in 0.35 /spl mu/m CMOS technology dissipates approximately 93 mW with a supply of 2.5 V and signal activity of 0.5, equivalent to 5.71 pJ/bit. Experimental results using a 16-bit reference bus design that can be externally programmed to operate in voltage, current or adaptive modes indicate a 50% reduction in power dissipation over current-mode (CM) sensing, and an improvement in interconnection delay and signaling bandwidth of 35%-70% and 66% over voltage-mode (VM) sensing, respectively. 相似文献
14.
HAROLD W. LEWIS III 《国际通用系统杂志》2013,42(1-2):97-114
Abstract On the subject of fuzzy set-based approximate reasoning, this paper attempts to present a perspective that is both rigorously stated and different from the standard approach as stated by Mamdani and many others. Functionally speaking, this alternative perspective produces results essentially the same as the standard one, and in fact we intend to prove that subject to certain assumptions the results will be exactly die same. We feel however that the alternative perspective offers advantages in that it makes a more appropriate and more understandable use of such concepts as fuzzy relations, the extension principle, and fuzzy composition. If indeed it can lead to a clearer and more widespread understanding of the approximate reasoning formalism then this could conceivably spark broader interest in fuzzy control and other applications. 相似文献
15.
16.
J. C. F. Millett N. K. Bourne N. T. Park G. Whiteman G. T. Gray III 《Journal of Materials Science》2011,46(11):3899-3906
The response of metallic materials to shock loading, like all loading regimes, is controlled largely by factors operating at the microscopic or atomic levels. Over the past few years, face-centred cubic (fcc) metals have received a level of attention where the role of features such as stacking fault energy and precipitation hardening have been investigated. We now turn our attention to body-centred cubic (bcc) metals. In the past, only tantalum, tungsten, and their alloys have received significant attention at high strain-rate conditions due to their use by the ordnance community. In particular, this investigation examines the shear strength of these materials at shock loading conditions. Previous results on tantalum, tungsten, and a tungsten heavy alloy are reviewed, and more recent experiments on niobium, molybdenum, and Ta–2.5 wt% W presented. Results are discussed in terms of known deformation mechanisms and variations of Peierl’s stress. 相似文献
17.
Sokolich M. Chen M.Y. Rajavel R.D. Chow D.H. Royter Y. Thomas S. III Fields C.H. Binqiang Shi Bui S.S. James Chingwei Li Hitko D.A. Elliott K.R. 《Solid-State Circuits, IEEE Journal of》2004,39(10):1615-1621
We describe a quasi-planar HBT process using a patterned implanted subcollector with a regrown MBE device layer. Using this process, we have demonstrated discrete SHBT with f/sub t/>250 GHz and DHBT with f/sub t/>230 GHz. The process eliminates the need to trade base resistance for extrinsic base/collector capacitance. Base/collector capacitance was reduced by a factor of 2 over the standard mesa device with a full overlap between the heavily doped base and subcollector regions. The low proportion of extrinsic base/collector capacitance enables further vertical scaling of the collector even in deep submicrometer emitters, thus allowing for higher current density operation. Demonstration ring oscillators fabricated with this process had excellent uniformity and yield with gate delay as low as 7 ps and power dissipation of 6 mW/CML gate. At lower bias current, the power delay product was as low as 20 fJ. To our knowledge, this is the first demonstration of high-performance HBTs and integrated circuits using a patterned implant on InP. 相似文献
18.
Yang Y. Markow M.S. Welch A.J. Rylander H.G. III 《Quantum Electronics, IEEE Journal of》1990,26(12):2232-2239
A multiple-layer phantom consisting of a thin absorbing layer sandwiched between two nonabsorbing layers was created to simulate laser-induced thermal lesions in the eye. The nonabsorbing layers consisted of clear egg white, and the thin (20-40-μm) absorbing layer was created with black spray paint. Heat generated in the absorbing layer during 0.5-10-s argon irradiation was conducted to the adjacent egg white. Sufficient heat produced a region of coagulation that was graphically evidenced by the characteristic whiteness of cooked egg white. Light reflected from the lesion was monitored with a video camera and used as a feedback signal to control irradiation time. The laser irradiation was automatically ended when the diameter of the reflectance parameter related to coagulation thickness reached a preselected value 相似文献
19.
Whelan C.S. Marsh P.F. Hoke W.E. McTaggart R.A. Lyman P.S. Lemonias P.J. Lardizabal S.M. Leoni R.E. III. Lichwala S.J. Kazior T.E. 《Solid-State Circuits, IEEE Journal of》2000,35(9):1307-1311
This paper reports on state of-the-art HEMT devices and circuit results utilizing 32% and 60% indium content InGaAs channel metamorphic technology on GaAs substrates. The 60% In metamorphic HEMT (MHEMT) has achieved an excellent 0.61-dB minimum noise figure with 11.8 dB of associated gain at 26 GHz. Using this MHEMT technology, two and three-stage Ka-band low-noise amplifiers (LNAs) have demonstrated <1.4-dB noise figure with 16 dB of gain and <1.7 with 26 dB of gain, respectively. The 32% In MHEMT device has overcome the <3.5-V drain bias limitation of other MHEMT power devices, showing a power density of 650 mW/mm at 35 GHz, with Vds=6 V 相似文献
20.
D. Richard Brown III H. Vincent Poor Sergio Verdú C. Richard Johnson Jr. 《Journal of Signal Processing Systems》2002,30(1-3):217-233
This paper considers the application of multiuser detection techniques to improve the quality of downlink reception in a multi-cell IS–95 digital cellular communication system. In order to understand the relative performance of suboptimum multiuser detectors including the matched filter detector, optimum multiuser detection in the context of the IS–95 downlink is first considered. A reduced complexity optimum detector that takes advantage of the structural properties of the IS–95 downlink and exhibits exponentially lower complexity than the brute-force optimum detector is developed. The Group Parallel Interference Cancellation (GPIC) detector, a suboptimum, low-complexity multiuser detector that also exploits the structure of the IS–95 downlink is then developed. Simulation evidence is presented that suggests that the performance of the GPIC detector may be near-optimum in several cases. The GPIC detector is also tested on a snapshot of on-air data measured with an omnidirectional antenna in an active IS–95 system and is shown to be effective for extracting weak downlink transmissions from strong out-of-cell cochannel interference. The results of this paper suggest that the GPIC detector offers the most performance gain in scenarios where weak downlink signals are corrupted by strong out-of-cell cochannel interference. 相似文献