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991.
Dynamic stress on MOSFETs with 900-MHz inverter-like waveforms as well as static (or dc) stress were evaluated experimentally. It showed that the degradation due to dynamic stress is less than that of dc stress for our test transistors. A compact model is used to evaluate the degradation in radio frequency performances, such as transconductance, cutoff frequency, linearity, and noise figure. A class-AB power amplifier is presented as an example to demonstrate the effect of dynamic stress on RF circuit performance.  相似文献   
992.
Improved Estimates for the Accuracy of Small Disjuncts   总被引:2,自引:0,他引:2  
Quinlan  J.R. 《Machine Learning》1991,6(1):93-98
Learning systems often describe a target class as a disjunction of conjunctions of conditions. Recent work has noted that small disjuncts, i.e., those supported by few training examples, typically have poor predictive accuracy. One model of this accuracy is provided by the Bayes-Laplace formula based on the number of training examples covered by the disjunct and the number of them belonging to the target class. However, experiments show that small disjuncts associated with target classes of different relative frequencies tend to have different error rates. This note defines the context of a disjunct as the set of training examples that fail to satisfy at most one of its conditions. An empirical adaptation of the Bayes-Laplace formula is presented that also makes use of the relative frequency of the target class in this context. Trials are reported comparing the performance of the original formula and the adaptation in six learning tasks.  相似文献   
993.
994.
We describe the performance of an experimental 1.5-μm lightwave transmission system operating at 8 Gbit/s over 68.3 km of single-mode fiber. The dispersion penalty is limited to 1 dB through the use of external modulation and is attributable to the intrinsic information bandwidth.  相似文献   
995.
Simulations with regional climate models (RCMs), carried out for the Rhine basin, have been analyzed in the context of implications of the possible future discharge of the Rhine river. In a first analysis, the runoff generated by the RCMs is compared to observations, in order to detect the way the RCMs treat anomalies in precipitation in their land surface component. A second analysis is devoted to the frequency distribution of area averaged precipitation, and the impact of selection of various driving global climate models.  相似文献   
996.
Assessed the validity of A. Ellis's (1971, 1973, 1981) contention that being religious was negatively correlated with mental health. 28 very religious, 34 atheist, and 33 religiously-neutral individuals seeking consultation were compared on the frequency and number of 8 reported problems. Contrary to Ellis's prediction, there were no significant differences among the groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
Certain hyperbolic systems of partial differential equations which are known to be uniformly asymptotically stabilizable using point sensors/actuators (S/A) are considered. The issue to be investigated is the effect on stability when point S/A's are replaced by "concentrated" S/ A's, that is, S/A's which average over small regions of the spatial domain. Although it is known that passing from point to concentrated S/ A's necessarily destroys uniform stability, a necessary and sufficient condition for strong stability is obtained in terms of the S/A weighting functions. In addition, in the special case of a cantilevered beam controlled by a single sensor/actuator pair concentrated at the free end, another, more robust type of stability is shown to hold, even when strong stability does not. The latter result shows that the system energy is bounded by a part which goes uniformly to zero at infinity and a residual which can be explicitly estimated in terms of the support of the weight functions and the initial energy. Furthermore, the residual energy converges to zero as the support reduces to the point at the free end of the beam.  相似文献   
998.
A semiconductor optical amplifier was developed for coarse wavelength-division-multiplexing (CWDM) operating over 1540-1620 nm (C-L band). A unique quantum-well structure was designed to meet the requirements for the CWDM operation such as wide bandwidth, low polarization-dependent gain, and high-saturation power at the short wavelength end of the band (1540 nm). Over the band, 24-dB maximum chip gain was obtained with less than 4.3-dB gain flatness and more than 14.6-dBm saturation power.  相似文献   
999.
It is well known that giant magnetoresistive (GMR) heads used for hard disk drives (HDD) are very sensitive to electrostatic discharge (ESD). In this paper, we describe a method of categorizing ESD damage modes from a standpoint of magnetic influences on the heads as observed by quasi-static test (QST) characteristics as well as electromagnetic characteristics like off-track profiles. In addition, we report an example of GMR stack interlayer diffusion which is one type of hard ESD damage. We also present an example of ESD damage that happened in an actual production process and its preventive measures as guidelines.  相似文献   
1000.
Glibenclamide has limited gastrointestinal absorption. Therefore, different concentrations of sodium lauryl sulphate and tweenR80 were included into the tablet formulations to increase the absorption of the drug and hence, to enhance the BSL lowering in rabbits and human volunteers suffering from maturity onset diabetes mellitus. It was found that the surfactants had enhanced both the rate and extent of BSL lowering in rabbits as well as in diabetic patients in higher concentrations present in the tablet formulations.  相似文献   
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