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41.
ABSTRACT

The side near-surface mounted (SNSM) method is a new flexural strengthening method for reinforced concrete (RC) beams which was proposed to allow near-surface mounted (NSM) strengthening to be applied on beams with small width. As a relatively new strengthening method, further studies are needed to determine the effects of strengthening parameters on the flexural performance of RC beams. In response to that, this paper presents a parametric study on the concrete cover separation failure of SNSM strengthened beams using a simulation method based on the moment-rotation (M/θ) approach.  相似文献   
42.
ABSTRACT

This paper proposes a novel hybrid strategy based on intelligent approaches to forecast electricity consumptions. The proposed forecasting strategy includes three main steps: (a) the evaluation of a correlation coefficient for socio-economic indicators on electric energy consumptions, (b) the classification of historical and socio-economic indicators using the proposed feature selection method, (c) the development of a new combined method using Adaptive Neuro-Fuzzy Inference System and Whale Optimization Algorithm to predict electrical energy consumptions. The simulation results have been tested and validated by real data sets achieved within 1992 and 2010 in two pilot cases in a developing country (Iran) and a developed one (Italy). The research findings pinpointed the greater accuracy and stability of the new developed method for electrical energy consumption forecasting compared to existing single and hybrid benchmark models.  相似文献   
43.
Avoiding collisions with obstacles in a clustered environment is a difficult task for autonomous vehicles. Deterministic algorithms cannot address all scenarios encountered and may fail to perform in dynamically changing environments. Neural networks, owing to their ability to map complex relationships between multiple input-output patterns, can learn the task of maneuvering around and in-between obstacles to reach a goal state. The Cerebellar Model Arithmetic Computer (CMAC) neural network in particular is based on a model of human sensory motor responses and can efficiently model responsive control actions. A CMAC neural network controller was developed and examined, in simulation, for its suitability to capture a driver's function of steering and braking. The performance of the controller was tested in a simulation of a moving platform (vehicle) encountering obstacles of various shapes, whereas the CMAC was trained only with limited shapes and scenarios. Preliminary simulation results have shown the CMAC's ability to successfully generalize its learned patterns to avoid obstacles after only a few training sessions. The CMAC output is generated in a computationally efficient manner with physically and economically realizable memory sizes. Therefore, real-time hardware implementation of the controller is feasible. This research demonstrates that the method has the ability to accommodate more complex scenarios.  相似文献   
44.
Two applications of the numerical method for the inverse heat conduction problem are presented. This numerical method calculates the surface temperature and heat flux using an internal experimental temperature evolution. In the case of aluminum alloys, the question of stability and sensitivity to error measurements is investigated and applied to actual quench cooling. For steel application (high heating and cooling rates), a new calculation procedure is developed to solve the problem of solution stability due to the nonmonotonous initial temperature profile generated by the superficial heating. This new calculation procedure allows the martensite tempered zones to be explained and localized.  相似文献   
45.
46.
This study aimed to evaluate the cytotoxicity effects of various polyethylene glycols (PEGs), and construction and characterization of polybutylcyanoacrylate (PBCA) nanoparticles. Cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on rat glioma C6 cell line, and PBCA nanoparticles were prepared by emulsion polymerization method. Also, the nanoparticles were characterized by dynamic light scattering and scanning electron microscopy. The findings showed that PEGs were approximately safe and cytotoxicity was inversely proportional with their molecular weights. In addition, the size of nanoparticles were increased with reducing molecular weights of PEGs. PEGs with negligible cytotoxicity and stabilizing functionality were demonstrated in this study.  相似文献   
47.
Electrically conductive coatings are mainly required for static charge dissipation and electromagnetic/radio frequency interference (EMI/RFI) shielding. Electrically conductive coatings are prepared by the incorporation of the metallic pigments/graphite onto the binder. In the present investigation graphite is used as the conductive filler and epoxy polymer as binder. Optimization of the solid content and pigment volume concentration (PVC) of the coating is done by varying the composition of the binder and pigment volume. To get the minimum resistivity value offered by the coating. The resistivity of the coating was measured by means of the four-probe resistivity method. The effect of inclusion of carbon black as additional pigment is also studied. The results are presented and discussed in this paper.  相似文献   
48.
This paper unveils two efficient free running (FR) quenching circuits with the aim of reducing quenching time (QT) to minimize avalanche charge. Likewise, one circuit is compactly designed with low power consumption, suitable for single-photon avalanche diode ( SPAD) with hold-off time below 10 ns. In second circuit, tunable hold-off and reset-time are provided within a wide range without decreasing QT, which are desirable in many applications. Proper operation and circuit uncertainty is assessed by Monte Carlo analysis in a standard 90-nm complementary metal-oxide semiconductor (CMOS) technology. In a bid to do a comparison between previously reported circuits and the proposed circuits, they are simulated with same SPAD model and parameters and results corroborate the proposed circuits guarantee active quenching time (AQT) of below 1 ns. Proposed circuits with current and area consumption of 0.74 μA, 32 μm2 for 7-ns dead time and 16.2 μA, 93 μm2 for 21-ns dead time are more efficient in terms of QT, area, and power consumption in comparison with other works.  相似文献   
49.
Ganiyev  Sabuhi  Azim Khairi  M.  Ahmad Fauzi  D.  Abdullah  Yusof  Hasbullah  N. F. 《Semiconductors》2017,51(12):1666-1670
Semiconductors - In this paper the effects of high energy (3.0 MeV) electrons irradiation over a dose ranges from 6 to 15 MGy at elevated temperatures 298 to 448 K on the current-voltage...  相似文献   
50.
The anelastic Stokes eigenmodes are computed for a fluid confined, in presence of gravity, between two horizontally infinite plates. These eigenmodes are described by one horizontal wave number k. The eigenvalues λ(k 2) are proved to be all negative. They depend monotonically upon k, behaving like k 2 for very large k. Two particular values of k are considered, i.e., k=2?π and k=0, and the stratification parameter of the equilibrium state is taken between 0 (incompressible approximation) and 10 (upper limit of the anelastic configuration). The k=2?π eigenvalue problem is solved numerically while the k=0 is solved both numerically and analytically. Two physical configurations are analyzed, one with no-slip boundary conditions imposed on both horizontal walls, and one with no-stress, while imposing no flow through these boundaries in both cases. The main results are: (i) the smaller the stratification, the larger the decay rate, (ii) the eigenmodes are localized in the lower part of the channel, their vertical extension increasing with the eigenmode spatial frequency, (iii) the Neumann eigenmode decay rates are smaller than their Dirichlet counterparts, except for k=0, where it is just the reverse, (iv) a general trend seems to emerge from the present study, regarding the way the numerical eigenvalues of an elliptic operator compare with the analytical ones, viz., the numerical spectrum overestimates (in absolute value) the analytical spectrum, slightly in the low frequency part of the spectrum and more and more strongly in the upper part.  相似文献   
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