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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Jepsen T.C. Laplante P.A. Williams J. Christensen K. Ferrante D. Chang J.M. Miller G. 《IT Professional》2004,6(4):10-17
What will software look like in the future? To answer this question, we conducted a survey of our editorial and industrial advisory boards, as well as a few outsiders. We constructed a set of 13 questions that we thought reflected the original query. We then circulated these questions to our boards, with a request to respond to the questions, or be extend them with additional are questions as appropriate. The answers were far ranging and sometimes surprising. 相似文献
992.
Understanding existing threats against mobile phones helps us better protect our information and prepare for future dangers. Mobile phones have evolved from their roots as analog walkie-talkies to full-scale Internet-enabled computers. Today, mobile phone handsets are arguably the dominant computer form factor consumers purchase. But having such powerful networked computers leads to a new class of malware: viruses, worms, and trojans specifically designed for the mobile environment. Merely enumerating known attacks doesn't help us understand all possible threats. Instead, we present a taxonomy of attacks against mobile phones that shows known as well as potential attacks. 相似文献
993.
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
994.
Surface degradation of polyamide nanocomposites caused by partial discharges using IEC (b) electrodes 总被引:1,自引:0,他引:1
Kozako M. Fuse N. Ohki Y. Okamoto T. Tanaka T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2004,11(5):833-839
Partial discharge (PD) degradation of polyamide both without nanoscale fillers (nanofillers) and with 2,4 and 5 wt% additions of nanofillers was investigated. Such materials were subjected to PDs using the IEC (b) electrodes for evaluation. Comparisons were made as to the surface roughness observed by scanning electron microscopy and atomic force microscopy. It was found that the change in the surface roughness is far smaller in specimens with nanofillers than those without nanofillers, and that the 2 wt% addition is sufficient for improvement of the surface roughness. Furthermore, it was elucidated that the difference of surface roughness of the degraded area due to PDs among the specimens originates from the difference in their crystalline structures. These results indicate that polyamide nanocomposite is more resistance to PDs than polyamide without nanofillers. 相似文献
995.
996.
997.
JIANGHong-yi LONGHai-shan ZHANGLian-meng 《武汉理工大学学报(材料科学英文版)》2004,19(2):55-56
The Mg2 Si-matrix thermoelectric material was stnthesized by low temperature solid-state renc-tion.This paper studies the effects of holding time and reaction temperatare on the particle size and the properties of the material, and also studies effects of doping elemental Sb, Te and their doping seqence on the properties of the materiol. The result shows that excessirely high temperature and elongated holding time of solid-state reaction are harmful, there is a range of partiele size to ensure optimum properties and the doping sequence of Sb or Te without influencing the properties. 相似文献
998.
We consider the parallel machine scheduling problem of minimizing the sum of quadratic job completion times. We first prove that the problem is strongly NP-hard. We then demonstrate by probabilistic analysis that the shortest processing time rule solves the problem asymptotically. The relative error of the rule converges in probability to zero under the assumption that the job processing times are independent random variables uniformly distributed in (0, 1). We finally provide some computational results, which show that the rule is effective in solving the problem in practice. 相似文献
999.
Monitoring Moisture Uptake and Delamination in CFRP-Reinforced Concrete Structures with Electrochemical Impedance Sensors 总被引:1,自引:0,他引:1
Electrochemical impedance spectroscopy (EIS) sensors have been used to inspect carbon fiber reinforced polymer (CFRP) -reinforced concrete structures exposed to a variety of test conditions. Similar specimens were also used to investigate the detection of delamination between the CFRP and the concrete using a modified wedge test configuration. The use of external electrodes attached to the CFRP surface, coupled with the embedded rebar, provided the best results. Equivalent circuit modeling was used to analyze the impedance spectra. Several circuit parameters, especially the capacitance and constant phase element (CPE) magnitude, correlated very well with both bonded area/delamination and moisture. Both parameters exhibit a linear relationship with delamination area. The capacitance also showed a linear relationship with moisture content while the CPE was more strongly dependent on moisture. Differences in the response of the specimens subjected to the different exposure conditions were seen and explained based on the moisture uptake of the various specimens. 相似文献
1000.
Shuvalov G. V. Selyatitskii V. G. Baikalov V. M. Bikmukhametov K. A. Vasil'eva T. V. 《Measurement Techniques》2004,47(8):795-801
The question of developing measurement provisions for the parameters of petroleum products is considered. The main technical features of a KLAN-1 mobile laboratory unit for analyzing petroleum products intended for rapid analysis of fuel and lubricating materials in storage and on sale are provided. 相似文献