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941.
The effects of an educational electronic book (e-book) on 149 five- to six-year-old kindergarteners’ emergent literacy levels were researched in two SES groups: low (LSES) (79 children) vs. middle (MSES) (70 children). In each SES group, children were randomly assigned to four groups. Three groups were assigned to work individually in one of three e-book activity modes: “Read story only”, “Read with dictionary”, or “Read and play” during three similar activity sessions and the fourth group served as a control which received the regular program of the kindergarten. Pre- and post-intervention emergent literacy measures included word meaning, word recognition, and phonological awareness. Results show that word meaning of children from both middle and low SES improved following the educational e-book activity, regardless of mode. Second, LSES children’s emergent literacy levels showed relatively greater improvement rates than did those of the MSES children. Third, children in the “Read with dictionary” and “Read and play” activity modes showed more improvement in their emergent literacy levels than did those in the “Read story only” mode. Implications for future research and for education are discussed. 相似文献
942.
Brain reading using full brain support vector machines for object recognition: there is no "face" identification area 总被引:1,自引:0,他引:1
Over the past decade, object recognition work has confounded voxel response detection with potential voxel class identification. Consequently, the claim that there are areas of the brain that are necessary and sufficient for object identification cannot be resolved with existing associative methods (e.g., the general linear model) that are dominant in brain imaging methods. In order to explore this controversy we trained full brain (40,000 voxels) single TR (repetition time) classifiers on data from 10 subjects in two different recognition tasks on the most controversial classes of stimuli (house and face) and show 97.4% median out-of-sample (unseen TRs) generalization. This performance allowed us to reliably and uniquely assay the classifier's voxel diagnosticity in all individual subjects' brains. In this two-class case, there may be specific areas diagnostic for house stimuli (e.g., LO) or for face stimuli (e.g., STS); however, in contrast to the detection results common in this literature, neither the fusiform face area nor parahippocampal place area is shown to be uniquely diagnostic for faces or places, respectively. 相似文献
943.
To improve the performance of scientific applications with parallel loops, dynamic loop scheduling methods have been proposed.
Such methods address performance degradations due to load imbalance caused by predictable phenomena like nonuniform data distribution
or algorithmic variance, and unpredictable phenomena such as data access latency or operating system interference. In particular,
methods such as factoring, weighted factoring, adaptive weighted factoring, and adaptive factoring have been developed based
on a probabilistic analysis of parallel loop iterates with variable running times. These methods have been successfully implemented
in a number of applications such as: N-Body and Monte Carlo simulations, computational fluid dynamics, and radar signal processing.
The focus of this paper is on adaptive weighted factoring (AWF), a method that was designed for scheduling parallel loops
in time-stepping scientific applications. The main contribution of the paper is to relax the time-stepping requirement, a
modification that allows the AWF to be used in any application with a parallel loop. The modification further allows the AWF
to adapt to load imbalance that may occur during loop execution. Results of experiments to compare the performance of the
modified AWF with the performance of the other loop scheduling methods in the context of three nontrivial applications reveal
that the performance of the modified method is comparable to, and in some cases, superior to the performance of the most recently
introduced adaptive factoring method.
相似文献
Ioana BanicescuEmail: |
944.
Jan Rosell Carlos Vázquez Alexander Pérez Pedro Iñiguez 《Journal of Intelligent and Robotic Systems》2008,53(3):223-245
Haptic devices allow a user to feel either reaction forces from virtual interactions or reaction forces reflected from a remote
site during a bilateral teleoperation task. Also, guiding forces can be exerted to train the user in the performance of a
virtual task or to assist him/her to safely teleoperate a robot. The generation of guiding forces relies on the existence
of a motion plan that provides the direction to be followed to reach the goal from any free configuration of the configuration
space (-space). This paper proposes a method to obtain such a plan that interleaves a sampling-based exploration of -space with an efficient computation of harmonic functions. A deterministic sampling sequence (with a bias based on harmonic
function values) is used to obtain a hierarchical cell decomposition model of -space. A harmonic function is iteratively computed over the partially known model using a novel approach. The harmonic function
is the navigation function used as motion plan. The approach has been implemented in a planner (called the Kautham planner) that, given an initial and a goal configuration, provides: (a) a channel of cells connecting the cell that contains
the initial configuration with the cell that contains the goal configuration; (b) two harmonic functions over the whole -space, one that guides motions towards the channel and another that guides motions within the channel towards the goal; and
(c) a path computed over a roadmap built with the free samples of the channel. The harmonic functions and the solution path
are then used to generate the guiding forces for the haptic device. The planning approach is illustrated with examples on
2D and 3D workspaces.
This work was partially supported by the CICYT projects DPI2005-00112 and DPI2007-63665. 相似文献
945.
Cecilia Laschi Gioel Asuni Eugenio Guglielmelli Giancarlo Teti Roland Johansson Hitoshi Konosu Zbigniew Wasik Maria Chiara Carrozza Paolo Dario 《Autonomous Robots》2008,25(1-2):85-101
This paper presents a sensory-motor coordination scheme for a robot hand-arm-head system that provides the robot with the capability to reach an object while pre-shaping the fingers to the required grasp configuration and while predicting the tactile image that will be perceived after grasping. A model for sensory-motor coordination derived from studies in humans inspired the development of this scheme. A peculiar feature of this model is the prediction of the tactile image. The implementation of the proposed scheme is based on a neuro-fuzzy module that, after a learning phase, starting from visual data, calculates the position and orientation of the hand for reaching, selects the best-suited hand configuration, and predicts the tactile feedback. The implementation of the scheme on a humanoid robot allowed experimental validation of its effectiveness in robotics and provided perspectives on applications of sensory predictions in robot motor control. 相似文献
946.
Product development is an important but also dynamic, lengthy and risky phase in the life of a new product. The optimisation of the product development phase through extensive knowledge of the involved procedures is believed to reduce the risks and improve the final product quality. Artificial intelligence and expert systems have been used successfully in optimising the development phase of some new products as it will be demonstrated by the first sections of this publication. This paper presents the first module of an expert system, a neural network architecture that could predict the reliability performance of a vehicle at later stages of its life by using only information from a first inspection after the vehicle’s prototype production. The paper demonstrates how a tool like neural networks can be designed and optimised for use in reliability performance predictions. Also, this paper presents an optimisation methodology that enabled the neural network to deal with the limited amount of available training data, common during new product development, and to finally achieve acceptable prediction performance with small error. A case example is presented to demonstrate the methodology. 相似文献
947.
This paper gives a detailed analysis of the error surfaces of certain recurrent networks and explains some difficulties encountered in training recurrent networks. We show that these error surfaces contain many spurious valleys, and we analyze the mechanisms that cause the valleys to appear. We demonstrate that the principle mechanism can be understood through the analysis of the roots of random polynomials. This paper also provides suggestions for improvements in batch training procedures that can help avoid the difficulties caused by spurious valleys, thereby improving training speed and reliability. 相似文献
948.
In this paper, we address the problem of agent loss in vehicle formations and sensor networks via two separate approaches: (1) perform a ‘self‐repair’ operation in the event of agent loss to recover desirable information architecture properties or (2) introduce robustness into the information architecture a priori such that agent loss does not destroy desirable properties. We model the information architecture as a graph G(V, E), where V is a set of vertices representing the agents and E is a set of edges representing information flow amongst the agents. We focus on two properties of the graph called rigidity and global rigidity, which are required for formation shape maintenance and sensor network self‐localization, respectively. For the self‐repair approach, we show that while previous results permit local repair involving only neighbours of the lost agent, the repair cannot always be implemented using only local information. We present new results that can be applied to make the local repair using only local information. We describe implementation and illustrate with algorithms and examples. For the robustness approach, we investigate the structure of graphs with the property that rigidity or global rigidity is preserved after removing any single vertex (we call the property as 2‐vertex‐rigidity or 2‐vertex‐global‐rigidity, respectively). Information architectures with such properties would allow formation shape maintenance or self‐localization to be performed even in the event of agent failure. We review a characterization of a class of 2‐vertex‐rigidity and develop a separate class, making significant strides towards a complete characterization. We also present a characterization of a class of 2‐vertex‐global‐rigidity. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
949.
Yu. E. Berezkin S. A. Borinskaya A. V. Kuznetsova O. V. Sen’ko 《Pattern Recognition and Image Analysis》2009,19(4):630-633
This work is devoted to the development and substantiation of intellectual data mining as applied to studying folklore and
mythological traditions. The approach is based on use of the functions of distance between traditions. The examples of application
of the methods developed to investigate the interrelation between folklore traditions of the American continent are considered. 相似文献
950.
A. O. Korepanov N. Yu. Ilyasova A. V. Kupriyanov 《Optical Memory & Neural Networks》2009,18(4):343-348
A problem of analyzing blood vessels on retinal images is considered. We suggest a method for extracting vessels using a wavelet
transform. The wavelet transform is modified by adding a wavelet rotation parameter and normalization with respect to the
signal energy within the wavelet carrier limits. The new methods, for constructing the vessel central lines based on the modified
wavelet transform, are being used for vessels geometrical parameters estimation. The parameters of vessels that are located
at the edge of the optic nerve disk are then used while diagnostic criteria formation for eye-ground pathological changes
determining. 相似文献