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151.
Cloud computing is a methodology and not a technology. Adaptation of cloud computing services for robotic applications is relatively straightforward while adaptation of underlying ideas will require a new design attitude. Cloud computing is a cost-effective and dynamic business model. Currently cloud robotics is understood as a client server methodology which enables robots utilize resources and services placed at centralized servers. These cloud servers treat robots as any other client computer offering them platform, infrastructure, process or algorithm as a service. HTM5 is an OMG MDA based multi-view meta-model for agent oriented development of cloud robotic systems. HTM5 encourages design of peer-to-peer service ecosystems based on an open registry and matchmaking mechanism. In peer-to-peer cloud robotics, a robot can trade its hardware, software and functional resources as a service to other robots in the ecosystem. The peer-to-peer trade in such systems may be driven by contracts and relationships between its member agents. This article discusses trade-view model of HTM5 methodology and its use in developing a cloud robotic ecosystem that implements peer-to-peer, contract based economy. The article also presents a case study with experiments that implement distributed artificial intelligence and peer-to-peer service oriented trade on simulated and real robot colonies.  相似文献   
152.
An adaptive power system stabilizer (APSS) employing a new self-optimizing pole shifting control strategy and its application to a power system are described in this paper. Based on an identified model of the system, the control is computed by an algorithm which shifts the closed-loop poles of the system to some optimal locations inside the unit circle in the z-domain to minimize a given performance criterion. With the self-optimization property, outside intervention in the controller design procedure is minimized, thus simplifying the tuning procedure during commissioning. Also, a new method of calculating the variable forgetting factor in real-time parameter identification is discussed. Studies show that the proposed APSS can provide good damping of the power system over a wide operating range and significantly improve the dynamic performance of the system  相似文献   
153.
154.
Ki-1 large cell anaplastic lymphoma is a recently described variant of malignant lymphoma. A retrospective study of 10 cases of Ki-1 lymphoma was carried out at the Armed Forces Institute of Pathology (AFIP) Rawalpindi to document its clinical and morphological features. The morphological features were evaluated by a study of paraffin embedded sections stained with haematoxylin and eosin stains. Immunohistochemical stains for BER-H2 and leucocyte common antigen (LCA) were performed in all cases. The age of the patients ranged from 2 to 60 years and male to female ratio was 2.3:1. Cervical lymphadenopathy was the most common presentation. Histologically, there was a complete effacement of the lymph node architecture in 8 cases. The Reed-Sternberg like cells were seen in 2 and histiocyte like cells in 7 cases. Immunohistochemically all cases were positive for BER-H2. It is suggested that the possibility of Ki-1 lymphoma should be considered in all cases of lymphoma with pleomorphic morphology.  相似文献   
155.
Copper tellurite glasses containing NiO, CoO and Lu2O3 were prepared by the melt-quenching technique. The composition used was 65TeO2-(35-x)CuO-xTMO (mol%), where TMO indicates NiO, CoO, Lu2O3, and for NiO- and CoO-doped glasses,x has the values 0, 0.5, 1 to 4, and for Lu2O3 doped glasses x=0 to 4. Electron spin resonance (ESR) spectra of all glasses were recorded at room temperature. The results on glasses doped with NiO, CoO and Lu2O3 are discussed in terms of oxidation-reduction, cross-relaxation and interelectronic repulsion processes, respectively. Cobalt oxide is found to be more effective in relaxing the ESR spectrum than nickel and lutetium oxides when substituted in copper tellurite glasses.  相似文献   
156.
Recent advances in the area of quantum functional devices are discussed. After a discussion of the functional device concept, resonant-tunneling bipolar transistors (RTBTs) with a double barrier in the base region are described. Design considerations for RTBTs with ballistic injection and the first observation of minority-electron ballistic RT are presented. RTBTs using thermionic injection and exhibiting a high peak-to-valley ratio at room temperature in the transfer characteristics are also described. Multiple-state RTBTs and their DC and microwave performance are then discussed. Circuit applications of RTBTs also are discussed. It is shown that RTBTs allow the implementation of many analog and digital circuit functions with a greatly reduced number of transistors and show considerable promise for multiple-valued logic. Experimental results on frequency multipliers and parity bit generators are presented. Analog-to-digital converters are memory circuits are also discussed. Two novel superlattice-base transistors are reported. Negative transconductance is achieved by suppression of injection into minibands. Gated quantum-well RT transistors are also discussed  相似文献   
157.
M. Malik  J. Mathew  J. Dey 《Acta Mechanica》2003,164(1-2):75-89
Summary. It is shown that the mechanism of linear instability of boundary-layer flows driven by favorable and adverse pressure gradients can be understood as a kinematic resonant interaction between inviscid and viscous partial modes. This kind of interaction has been proposed by Baines, Majumdar and Mitsudera [4] for the Blasius boundary layer. Here, this proposal has been examined for more general flows and quantitative confirmation has been obtained. Piecewise linear approximations of Falkner-Skan velocity profiles are taken as the mean flows. To understand the mechanism, it proves sufficient to examine eigensolutions of the viscous part obtained by enforcing no-slip. This leads to the prediction of the parameters for maximum growth in the space of Reynolds number and wave number. In the case of adverse pressure gradient the inviscid flow itself is unstable due to the presence of an inflexion point. We show that the instability mechanism stated above has a role in the flows of this kind, too.  相似文献   
158.
Morphometric techniques were employed to assess perineurial capillary abnormalities in the sural nerve of 20 diabetic patients with neuropathy and 10 normal control subjects. Structural abnormalities were related to quantitative neurophysiological and neuropathological measures of neuropathy. Perineurial capillary endothelial cell area (P < 0.001) and endothelial cell profile number (P < 0.01) were increased and luminal area (P < 0.001) was reduced in diabetic patients when compared with control subjects. A significant relationship was observed between endothelial cell hyperplasia and measures of neuropathic severity. These findings provide evidence for perineurial capillary luminal occlusion due primarily to both endothelial cell hypertrophy and hyperplasia. Such a reduction in luminal size is expected to reduce transperineurial and hence endoneurial blood flow, resulting in endoneurial hypoxia and hence human diabetic neuropathy.  相似文献   
159.
We present a detailed experimental and theoretical investigation of hot electron effects occurring in AlGaAs/GaAs Heterojunction Bipolar Transistors (HBT's) operating at low current densities. Electrons heated by the strong electric field at the base-collector junction give rise to impact ionization and light emission. A new general purpose weighted Monte Carlo procedure has been developed to study such effects. The importance of dead-space effects on the multiplication factor of the device is demonstrated. Good agreement is found between theory and experiment  相似文献   
160.
We compare ECR plasma etch fabrication of self-aligned thin emitter carbondoped base InGaAs/InP DHBT structures using either CH4/H2/Ar or BCl3/N2 etch chemistries. Detrimental hydrogen passivation of the carbon doping in the base region of our structure during CH4/H2/Ar dry etching of the emitter region is observed. Initial conductivity is not recovered with annealing up to a temperature of 500°C. This passivation is not due to damage from the dry etching or from the MOMBE growth process, since DHBT structures which are ECR plasma etched in BCl3/N2 have the same electrical characteristics as wet etched controls. It is due to hydrogen implantation from the plasma exposure. This is supported with secondary ion mass spectroscopy profiles of structures which are etched in CH4/D2/Ar showing an accumulation of deuterium in the C-doped base region.  相似文献   
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