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991.
992.
Knowledge and Information Systems - In the field of time series data mining, the accuracy of the simple, but very successful nearest neighbor (NN) classifier directly depends on the chosen...  相似文献   
993.
The paper discusses the numerical model and provides the analysis of a graphene coaxial line suitable for sub-micron sensors and other applications utilized especially in biomedicine. In the wider perspective, the areas and disciplines targeted by the presented concept include biology, medicine, prosthetics, and microscopic solutions for modern actuators or SMART elements. The proposed hybrid numerical model is based on analyzing a periodic structure with high repeatability, and it exploits the conception of a graphene polymer having its basic dimension in nanometers. The model simulates both the transient analysis and the actual random motion of an electric charge in the structure as the source of spurious signals, and it also considers the harmonic signal propagation along the structure; moreover, the model examines whether and how the signal will be distorted at the beginning of the modeled electric line, given the various termination versions. The results of the analysis are necessary for further use of the designed sensing devices based on graphene structures.  相似文献   
994.
Two solutions to the polynomial filter’s transfer function synthesis problem are considered for comparison in the frequency and time domain: the broad class of filters with a critical monotonic amplitude characteristic (CMAC) in the passband and filters which use Chebyshev (C) polynomials. To complete the synthesis procedure for linear phase applications, group delay correctors are considered, for which a convenient approximation procedure is proposed here. Comparisons of the original functions and the corrected ones are performed in the frequency and time domain. It is shown that when CMAC and C are compared as such, the latter is by no means preferable from the selectivity point of view, while the opposite stands when the comparison is based on passband amplitude distortions. When phase-corrected filtering functions are compared, based on circuit complexity and time domain performance, the CMAC are shown to be preferable.  相似文献   
995.
The Sentinel-2 satellite currently provides freely available multispectral bands at relatively high spatial resolution but does not acquire the panchromatic band. To improve the resolution of 20 m bands to 10 m, existing pansharpening methods (Brovey transform [BT], intensity–hue–saturation [IHS], principal component analysis [PCA], the variational method [P + XS], and the wavelet method) required adjustment, which was achieved using higher resolution multispectral bands in the role of a panchromatic band to fuse bands at a lower spatial resolution. After preprocessing, six bands at lower resolution were divided into two groups because some image fusion methods (e.g. BT, IHS) are limited to a maximum of three input bands of a lower resolution at a time. With respect to the spectral range, the higher resolution band for the first group was synthesized from bands 4 and 8, and band 8 was selected for the second group. Given that one of the main remote sensing applications is land-cover classification, the classification accuracy of the fusion methods was assessed as well as the comparison with reference bands and pixels. The supervised classification methods were Maximum Likelihood Classifier, artificial neural networks, and object-based image analysis. The classification scheme contained five classes: water, built-up, bare soil, low vegetation, and forest. The results showed that most of the fusion methods, particularly P + XS and PCA, improved the overall classification accuracy, especially for the classes of forest, low vegetation, and bare soil and in the detection of coastlines. The least satisfying results were obtained from the wavelet method.  相似文献   
996.
An indium oxide‐based precursor solution has been developed by spin coating method. In order to apply this material to mass production, material, process, and equipment optimizations for slot die coating have been implemented. Slot die coating is a cost‐effective and scalable process and already applied to photoresist materials in the display industry. The indium oxide‐based precursor solution has been coated on bare glasses and thin‐film transistor substrates by a mass production‐type slot die coater. Mobility of over 10 cm2/Vs is achieved for the first time for a large area at an annealing temperature of 350 °C. The homogeneity of the film will be presented.  相似文献   
997.
The paper deals with the modeling and control of redundantly actuated parallel mechanisms. The redundant actuation means the redundant number of actuators, that is, more actuators than degrees of freedom of the mechanism. These machines bring the possibility of removing the backlash by the so-called antibacklash control. However, control of such a structure suffers from several new control problems like the danger of mutual fighting of the redundant actuators. This is especially problematic if the geometric imperfections appear. The presented solution is based on the usage of robust sliding mode control for uncertain dynamics. The paper explains classic approach of sliding mode control and its new modification based on the uniform usage of all actuators replaced by the fictitious auxiliary drives. The verification of the proposed algorithms is presented by two planar mechanisms with four actuators and three degrees of freedom. The first one is the fiber-driven mechanism, and the second one is the rigid 4RRR mechanism “Crosshead.”  相似文献   
998.
Linear time-invariant discrete-time plant, with no restrictions on the form of the state equation and with scalar control, is considered. The exponentially stabilizing state feedback control algorithm is developed by Lyapunov’s second method leading to the variable structure system with chattering free sliding modes. Essentially, the control algorithm drives the system from an arbitrary initial state to a prescribed so-called sliding subspace S, in finite time and with prescribed velocity estimate. Inside the sliding subspace S, the system is switched to the sliding mode regime and stays in it forever. The proposed algorithm is tested on the real system in practice, direct current (DC) servo motor, and simulation and experimental results are given. Also, it is compared with another already known algorithm from literature.  相似文献   
999.
Multimedia Tools and Applications - Overlapped fingerprints are often found in latent fingerprints lifted from crime scenes and in live-scan fingerprint images when the surface of fingerprint...  相似文献   
1000.
In this paper we present Brushables—a novel approach to example‐based painting that respects user‐specified shapes at the global level and preserves textural details of the source image at the local level. We formulate the synthesis as a joint optimization problem that simultaneously synthesizes the interior and the boundaries of the region, transferring relevant content from the source to meaningful locations in the target. We also provide an intuitive interface to control both local and global direction of textural details in the synthesized image. A key advantage of our approach is that it enables a “combing” metaphor in which the user can incrementally modify the target direction field to achieve the desired look. Based on this, we implement an interactive texture painting tool capable of handling more complex textures than ever before, and demonstrate its versatility on difficult inputs including vegetation, textiles, hair and painting media.  相似文献   
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