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171.
《Comptes Rendus Physique》2014,15(5):415-420
Electromagnetic intelligence and attacks pose unacceptable risks for the security and safety of critical networks and more specifically the power network. In this paper, it is pointed out how the use of the excess model allows one to extrapolate the very high level of spurious compromising emanations induced by an information system in realistic power network models. It is shown that the design of appropriate protections and risk management methodologies can be enhanced thanks to the extreme value statistics.  相似文献   
172.
The loading criteria of the Lagrangian strain-space formulation of rate-independent plasticity are compared with those of Nguyen and Bui and those of Kuhn–Tucker type. When the latter two sets of conditions are expressed in a fully strain-space form, their relationship to the loading criteria of the strain-space formulation becomes transparent. To cite this article: J. Casey, C. R. Mecanique 330 (2002) 285–290.  相似文献   
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Magnetic study and Mössbauer resonance measurements of the tellurites Fe2Te3O9 and Fe2Te4O11 characterize antiferromagnetic ordering. The transition temperatures determined by Mössbauer resonance, are 34 and 27 K, respectively. At 295 K the values of chemical shifts, 0.35 and 0.39 mm/sec, are typical of high-spin Fe(III) in octahedral coordination. Neutron powder diffraction was used to determine the magnetic structure of Fe2Te4O11 at 4.2 K. It shows antiferromagnetic interactions between Fe3+ ions belonging to [Fe2O10] groups. The magnetic space group is P2a21c.  相似文献   
175.
Halobacterium halobium is a typical kind of extremely halophilic bacterium. Combined with the antibiotic resistance assay, the microcalorimetric method was used to study the promoter function of the cloned DNA fragments from Halobacterium halobium J7 plasmid pHH205 in Escherichia coli TG1. The promoter probe vector, plasmid pKK232-8, was used to form the recombinants. The DNA fragment, which is the promoter for the chloramphenicol acetyl transferase (CAT) gene in plasmid pKK232-8, is about 800 bp, and the chloramphenicol resistance level presented by IC50 is about 200 μg·mL^-1, which suggests a high promoter activity. The conclusions show that there probably exist double-function or trinary-function gene promoters in Halobacterium halobium, and Archaea may contain rich genetic resources.  相似文献   
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177.
《Comptes Rendus Physique》2016,17(10):1060-1071
We review recent developments in nonlinear quantum transport through nanostructures and mesoscopic systems driven by thermal gradients or in combination with voltage biases. Low-dimensional conductors are excellent platforms for analyzing both the thermoelectric and heat dynamics beyond the linear response because, due to their small size, a small temperature difference applied across regions gives rise to large thermal biases. We offer a theoretical discussion based on the scattering approach to highlight the differences between the linear and the nonlinear regimes of transport. We discuss recent experiments on quantum dots and molecular junctions subjected to strong temperature differences. Theoretical predictions concerning the Kondo effect and heat rectification proposals are briefly examined. An important issue is the calculation of thermoelectric efficiencies including nonlinearities. Cross Seebeck effects and nonlinear spin filtering arise in superconductors and topological insulators, while mixed noises between charge and heat currents are also considered. Finally, we provide an outlook on the possible future directions of the field.  相似文献   
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文章阐述了一种基于FPGA+DSP构架的数据采集系统的设计与实现。该系统中FPGA先进行模拟量、频率量、离散量输入的采集,以及RS-422、ARINC429总线的数据接收工作,然后将采集和接收到的数据按约定数据格式,通过HPI发送至DSP,DSP按协议要求完成数据的运算、组合等处理后,FPGA控制HPI读取处理结果并控制离散量输出模块、RS422、ARINC429总线按照所需的数据格式和通讯周期将数据输出至相对应的系统。该系统具有丰富的接口,能满足多种类、不同时序周期的总线通讯。  相似文献   
180.
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