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1.
With the Smart Grid revolution and the increasing interest in renewable energy sources, the management of the electricity consumption and production of individual households and small residential communities is becoming an essential element of new power systems. The electric energy chain can greatly benefit from a flexible interaction with end-users based on the optimization of load profiles and the exploitation of local generation and energy storage. This paper proposes a framework for the development of a complete energy management system for individual residential units and small communities of domestic users, taking into account both the power system and the final users’ perspectives. All the main elements of the framework are considered, and contributions are provided on the users’ habits profiling, electricity generation forecast, energy load, and storage optimization. Specifically, we propose a linear regression model to predict the photovoltaic panels production, a stochastic method to forecast the home appliances usage, and two optimization models to optimize the electricity management of residential users with the goal of minimizing their bills. The study shows that it is possible to reduce the energy bill of residential users through the electricity optimization driven by dynamic energy prices. Moreover, remarkable improvements of the electric grid efficiency can be achieved with the cooperation among users, confirming that services for the coordination of the demand of groups of users allow huge benefits on the power system performance.  相似文献   
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This paper presents a method to compute response sensitivities of finite element models of structures based on a three‐field mixed formulation. The methodology is based on the direct differentiation method (DDM), and produces the response sensitivities consistent with the numerical finite element response. The general formulation is specialized to frame finite elements and details related to a newly developed steel–concrete composite frame element are provided. DDM sensitivity results are validated through the forward finite difference method (FDM) using a finite element model of a realistic steel–concrete composite frame subjected to quasi‐static and dynamic loading. The finite element model of the structure considered is constructed using both monolithic frame elements and composite frame elements with deformable shear connection based on the three‐field mixed formulation. The addition of the analytical sensitivity computation algorithm presented in this paper extends the use of finite elements based on a three‐field mixed formulation to applications that require finite element response sensitivities. Such applications include structural reliability analysis, structural optimization, structural identification, and finite element model updating. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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Mice homozygous for a disruption in the Mdr2 gene (Mdr2 (-/-) mice) lack the Mdr2 P-glycoprotein (P-gp) in the canalicular membrane of the hepatocyte and are unable to excrete phosphatidylcholine into the bile. These mice develop a nonsuppurative cholestatic liver disease, presumably caused by the high concentrations of free cytotoxic bile acids in bile. We generated transgenic mice that express the human homolog of Mdr2, MDR3, specifically in the liver by the use of an albumin promoter. In these mice the MDR3 P-gp is exclusively located in the canalicular membrane of hepatocytes and phospholipid excretion into bile is restored. Mice that contain the same amount of MDR3 P-gp as that of Mdr2 P-gp in wild-type mice, also excrete the same amount of phospholipids. No histopathological abnormalities were observed in the livers of these mice. In mice that express MDR3 at a higher or lower level, the phospholipid excretion correlated with the amount of MDR3 P-gp. We conclude that the human MDR3 P-gp is functionally homologous to the murine Mdr2 P-gp and that it can fully replace this P-gp in Mdr2 (-/-) mice, restoring the excretion of phospholipids into the bile. The phospholipid excretion is limited by the amount of MDR3 or Mdr2 P-gp. The excretion of cholesterol is not tightly coupled to the excretion of phospholipids in these mice, because a very low phospholipid excretion level is sufficient to give almost wild-type cholesterol excretion into the bile.  相似文献   
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SPIDER, the ion source test bed in the ITER neutral beam test facility, is under construction and its operation is expected to start in 2014. Control and data acquisition for SPIDER are undergoing final design. SPIDER CODAS, as the control and data acquisition system is referred to, is requested to manage 25 plant units, to acquire 1000 analogue signals with sampling rates ranging from a few S/s to 10 MS/s, to acquire images with up to 100 frames per second, to operate with long pulses lasting up to 1 h, and to sustain 200 MB/s data throughput into the data archive with an annual data storage amount of up to 50 TB. SPIDER CODAS software architecture integrates three open-source software frameworks each addressing specific system requirements. Slow control exploits the synergy among EPICS and Siemens S7 programmable controllers. Data handling is by MDSplus a data-centric framework that is geared towards the collection and organization of scientific data. Diagnostics based on imaging drive the design of data throughput and archive size. Fast control is implemented by using MARTe, a data-driven, object-oriented, real-time environment. The paper will describe in detail the progress of the system hardware and software architecture and will show how the software frameworks interact to provide the functions requested by SPIDER CODAS. The paper will focus on how the performance requirements can be met with the described SPIDER CODAS architecture, describing the progress achieved by carrying out prototyping activities.  相似文献   
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Granisetron, Ondansetron and Tropisetron, three 5-HT3 antagonists showing anti-emetic activity, were analysed by HPLC on lipophilic stationary phases. The addition of an amine or quaternary ammonium salt to the eluents was a powerful tool in the analysis of these basic substances. The influence on chromatographic parameters of pH, ionic strength and various counter-ions in the aqueous phase as well as of different organic modifiers is discussed. Some of the proposed experimental conditions allow a more strictly partition-based separation mechanism and can produce chromatographic parameters suitable for structure-activity studies. These experimental conditions are also suitable for analysis of the considered compounds in pharmaceutical dosage forms or in biological fluids.  相似文献   
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Dynamic traffic is becoming important in WDM networks. In the transition towards full dynamic traffic, WDM networks optimized for a specific set of static connections will most likely also be used to support on-demand lightpath provisioning. Our paper investigates the issue of routing of dynamic connections in WDM networks which are also loaded with high-priority protected static connections. By discrete-event simulation we compare various routing strategies in terms of blocking probability and we propose a new heuristic algorithm based on an occupancy cost function which takes several possible causes of blocking into account. The behavior of this algorithm is tested in well-known case-study mesh networks, with and without wavelength conversion. Moreover, Poissonian and non-Poissonian dynamic traffics are considered.  相似文献   
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Hardness measurements by Vickers and Brinell indentations are liable to error, even when performed by experienced operators. The authors examine the problems involved in such measurements and the standards and specifications under which they are made. They conclude that some causes of error not yet fully understood and the effects of differences in optical microscopes are not taken into account. Greater standardisation of measurement systems has become necessary.  相似文献   
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