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991.
Geiger iterative algorithm is very strict to the initial value. If the initial value is not selected suitably, it is difficult to enter the convergence range, thus increasing the number of iterations. The acoustic emission source location based on phase difference time delay estimation method reduces the error of acoustic emission location, but it has some shortcomings in accuracy. Based on the above problems, this paper presents a new algorithm for Geiger optimization based on source localization. Firstly, the initial value of Geiger is obtained by using the phase difference method. Then, the optimal solution is obtained by the iterative solution of Geiger algorithm and the least square method. The simulation results show that this method can effectively solve the problem of selecting the initial value of Geiger, so that it can quickly enter the convergence range, improving the convergence speed and positioning accuracy, comparing the positioning results of the United States PCI-2 type acoustic emission instrument, the average error reduced by about 5 mm.  相似文献   
992.
993.

Automatic online multiple pedestrian tracking is a rather important and challenging task in the field of machine vision. A new multiple pedestrian tracking system is proposed in this paper, which combines pedestrian detection, motion prediction, target matching and adaptive location adjustment methods. The clip-split strategy was adopted for optimization of the detected pedestrian candidates, which resulted in great improvement of the tracking accuracies, especially when the marginal areas of the detected target candidates contained background scenes. For each frame, the proposed adaptive location adjustment method was used to adjust the location and scale of the targets to deal with drifting problems where necessary, especially after severe occlusions. Experimental results on three challenging real-world datasets demonstrated that the proposed tracker has excellent performance over other state-of-the-art trackers based on MOT metrics.

  相似文献   
994.
The profile of the nano-mold can also influence the replication precision of the final 2D polymer nanochannels. In the present work, the aspect ratio of the nano-mold, the duty ratio of the nano-mold, and the thickness ratio were investigated by numerical simulation method. The replication precision of the 2D polymer nanochannels is evaluated by imprinting ratio. The simulation results show that the lower aspect ratio and duty ratio is associated with higher imprinting ratio. However, the imprinting ratio increases with the thickness ratio at beginning and then keeps nearly unchanged as the thickness ratio continuously increases. The proper thickness ratio is two. The imprinting temperature and pressure were also optimized according the imprinting ratio. The simulation results show that the optimal imprinting temperature and pressure were 120 °C and 1.5 MPa, respectively.  相似文献   
995.
Machine vision is an excellent tool for inspecting a variety of items such as textiles, fruit, printed circuit boards, electrical components, labels, integrated circuits, machine tools, etc. This paper presents an intelligent system that incorporates machine vision with artificial intelligent networks to automatically inspect thermal fuses. An effective inspection flow is proposed to detect four commonly seen defects, including black-dot, small-head, bur, and flake during the production of thermal fuses. Backpropagation neural networks and learning vector quantization performance is compared in detecting the bur defect because of its illegibility. Different numbers of defective samples were screened out from a production line in a case study company and used to demonstrate the efficacy of the proposed system. Currently, the proposed inspection system is operating at the case study company, replacing four to six human inspectors. The system not only ensures the quality of the thermal fuses produced, but also reduced the cost of manual visual inspection.  相似文献   
996.
This article presents a simulation method for the design of a digitally controlled oscillator (DCO). Electromagnetic (EM) simulations are essential and inevitable for modern LC oscillator design. Although EM‐simulators provide high accuracy, the EM‐simulation time is very long when metal‐oxide‐metal (MoM) capacitors are present. The proposed frame‐based EM‐simulation can significantly reduce the EM‐simulation time even in the presence of MoM capacitors without influencing the accuracy. To verify the proposed method, a DCO was fabricated using a 55‐nm CMOS process. Measurements of the DCO are in good agreement with the frame‐based post‐layout simulation results. In addition, the DCO has good performances with a low power consumption of approximately 0.68 mW.  相似文献   
997.
Multiple instance learning attempts to learn from a training set consists of labeled bags each containing many unlabeled instances. In previous works, most existing algorithms mainly pay attention to the ‘most positive’ instance in each positive bag, but ignore the other instances. For utilizing these unlabeled instances in positive bags, we present a new multiple instance learning algorithm via semi-supervised laplacian twin support vector machines (called Miss-LTSVM). In Miss-LTSVM, all instances in positive bags are used in the manifold regularization terms for improving the performance of classifier. For verifying the effectiveness of the presented method, a series of comparative experiments are performed on seven multiple instance data sets. Experimental results show that the proposed method has better classification accuracy than other methods in most cases.  相似文献   
998.
A variety of saliency models based on different schemes and methods have been proposed in the recent years, and the performance of these models often vary with images and complement each other. Therefore it is a natural idea whether we can elevate saliency detection performance by fusing different saliency models. This paper proposes a novel and general framework to adaptively fuse saliency maps generated using various saliency models based on quality assessment of these saliency maps. Given an input image and its multiple saliency maps, the quality features based on the input image and saliency maps are extracted. Then, a quality assessment model, which is learned using the boosting algorithm with multiple kernels, indicates the quality score of each saliency map. Next, a linear summation method with power-law transformation is exploited to fuse these saliency maps adaptively according to their quality scores. Finally, a graph cut based refinement method is exploited to enhance the spatial coherence of saliency and generate the high-quality final saliency map. Experimental results on three public benchmark datasets with state-of-the-art saliency models demonstrate that our saliency fusion framework consistently outperforms all saliency models and other fusion methods, and effectively elevates saliency detection performance.  相似文献   
999.
The tagging systems have been studied by many researchers in the past decade. Tagging methods have been widely used on the web for searching and recommending images. Social tags are the keywords annotated by users to the images, which contains the information for searching and classifying the images. Tag recommendation system allows mitigating the individual preferences to annotate and recommender images. However, irrelevant and noise tags are frequently included in tags. In this paper, we propose image tag recommendation based on the friends’ relationships in social network (TRboFS) to recommender tags for a new image, both the tags assigned to the favorite images and the friendships of the users who upload the image are employed to predict the tags of the images. Empirical analyses on real datasets show that the proposed approach achieves superior performance to existing approaches.  相似文献   
1000.
We consider the optimal pricing problem for a model of the rich media advertisement market, that has other related applications. Our model differs from traditional position auctions in that we consider buyers whose demand might be multiple consecutive slots, which is motivated by modeling buyers who may require these to display a large size ad. We study three major pricing mechanisms, the Bayesian pricing model, the maximum revenue market equilibrium model and an envy-free solution model. Under the Bayesian model, we design a polynomial-time computable truthful mechanism that optimizes the revenue. For the market equilibrium paradigm, we find a polynomial-time algorithm to obtain the maximum revenue market equilibrium solution. In the envy-free setting, an optimal solution is presented for the case where the buyers have the same demand for the number of consecutive slots. We present results of a simulation that compares the revenues from the above schemes.  相似文献   
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