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981.
Currently, embedded systems have been widely used for ubiquitous computing environments including digital setup boxes, mobile
phones, and USN (Ubiquitous Sensor Networks). The significance of security has been growing as it must be necessarily embedded
in all these systems. Up until now, many researchers have made efforts to verify the integrity of applied binaries downloaded
in embedded systems. The research of problem solving is organized into hardware methods and software-like methods. In this
research, the basic approach to solving problems from the software perspective was employed. From the software perspective,
unlike in the existing papers (Seshadri et al., Proc. the IEEE symposium on security and privacy, 2004; Seshadri et al., Proc. the symposium on operating systems principals, 2005) based on the standardized model (TTAS.KO-11.0054.
2006) publicized in Korea, there is no extra verifier and conduct for the verification function in the target system. Contrary
to the previous schemes (Jung et al. , 2008; Lee et al., LNCS, vol. 4808, pp. 346–355, 2007), verification results are stored in 1 validation check bit, instead of storing signature value for application binary files
in the i-node structure for the purpose of reducing run-time execution overhead. Consequently, the proposed scheme is more
efficient because it dramatically reduces overhead in storage space, and when it comes to computing, it performs one hash
algorithm for initial execution and thereafter compares 1 validation check bit only, instead of signature and hash algorithms
for every application binary. Furthermore, in cases where there are frequent changes in the i-node structure or file data
depending on the scheme application, the scheme can provide far more effective verification performance compared to the previous
schemes. 相似文献
982.
Sangseok Yun Bongjin Jun Daijin Kim Jaewoong Kim Sukhan Lee Mun-Taek Choi Munsang Kim Joong-Tae Park Jae-Bok Song 《Journal of Intelligent and Robotic Systems》2012,67(2):79-99
This paper describes a scheme for proactive human search for a designated person in an undiscovered indoor environment without human operation or intervention. In designing and developing human identification with prior information a new approach that is robust to illumination and distance variations in the indoor environment is proposed. In addition, a substantial exploration method with an octree structure, suitable for path planning in an office configuration, is employed. All these functionalities are integrated in a message- and component-based architecture for the efficient integration and control of the system. This approach is demonstrated by succeeding human search in the challenging robot mission of the 2009 Robot Grand Challenge Contest. 相似文献
983.
Seok-Ho Yoon Jung-Hwan Shin Sang-Wook Kim Sunju Park Jae Bum Lee 《Information Sciences》2012,184(1):215-229
In the blogosphere, there exist posts relevant to a particular subject and blogs that show interest in the subject. In this paper, we define a set of such posts and blogs as a blog community and propose a method for extracting the blog community associated with a particular subject. The proposed method is based on the idea that the blogs who have performed actions (e.g., read, comment, trackback, scrap) to the posts of a particular subject are the ones with interest in the subject, and that the posts that have received actions from such blogs are the ones that contain the subject. The proposed method starts with a small number of manually-selected seed posts containing the subject. Then, the method selects the blogs that have performed actions to the seed posts over some threshold and the posts that have received actions over some threshold. Repeating these two steps gradually expands the blog community. This paper presents various techniques to improve the accuracy of the proposed method. The experimental results show that the proposed method exhibits a higher level of accuracy than the methods proposed in prior research. This paper also discusses business applications of the extracted community, such as target marketing, market monitoring, improving search results, finding power bloggers, and revitalization of the blogosphere. 相似文献
984.
Object recognition is a well studied but extremely challenging field. We present a novel approach to feature construction for object detection called Evolution-COnstructed Features (ECO features). Most current approaches rely on human experts to construct features for object recognition. ECO features are automatically constructed by uniquely employing a standard genetic algorithm to discover multiple series of transforms that are highly discriminative. Using ECO features provides several advantages over other object detection algorithms including: no need for a human expert to build feature sets or tune their parameters, ability to generate specialized feature sets for different objects, no limitations to certain types of image sources, and ability to find both global and local feature types. We show in our experiments that the ECO features compete well against state-of-the-art object recognition algorithms. 相似文献
985.
Accurate depth estimation is a challenging, yet essential step in the conversion of a 2D image sequence to a 3D stereo sequence. We present a novel approach to construct a temporally coherent depth map for each image in a sequence. The quality of the estimated depth is high enough for the purpose of2D to 3D stereo conversion. Our approach first combines the video sequence into a panoramic image. A user can scribble on this single panoramic image to specify depth information. The depth is then propagated to the remainder of the panoramic image. This depth map is then remapped to the original sequence and used as the initial guess for each individual depth map in the sequence. Our approach greatly simplifies the required user interaction during the assignment of the depth and allows for relatively free camera movement during the generation of a panoramic image. We demonstrate the effectiveness of our method by showing stereo converted sequences with various camera motions. 相似文献
986.
The feature of brevity in mobile phone messages makes it difficult to distinguish lexical patterns to identify spam. This paper proposes a novel approach to spam classification of extremely short messages using not only lexical features that reflect the content of a message but new stylistic features that indicate the manner in which the message is written. Experiments on two mobile phone message collections in two different languages show that the approach outperforms previous content-based approaches significantly, regardless of language. 相似文献
987.
Feature selection plays an important role in pattern recognition systems. In this study, we explored the problem of selecting effective heart rate variability (HRV) features for recognizing congestive heart failure (CHF) based on mutual information (MI). The MI-based greedy feature selection approach proposed by Battiti was adopted in the study. The mutual information conditioned by the first-selected feature was used as a criterion for feature selection. The uniform distribution assumption was used to reduce the computational load. And, a logarithmic exponent weighting was added to model the relative importance of the MI with respect to the number of the already-selected features. The CHF recognition system contained a feature extractor that generated four categories, totally 50, features from the input HRV sequences. The proposed feature selector, termed UCMIFS, proceeded to select the most effective features for the succeeding support vector machine (SVM) classifier. Prior to feature selection, the 50 features produced a high accuracy of 96.38%, which confirmed the representativeness of the original feature set. The performance of the UCMIFS selector was demonstrated to be superior to the other MI-based feature selectors including MIFS-U, CMIFS, and mRMR. When compared to the other outstanding selectors published in the literature, the proposed UCMIFS outperformed them with as high as 97.59% accuracy in recognizing CHF using only 15 features. The results demonstrated the advantage of using the recruited features in characterizing HRV sequences for CHF recognition. The UCMIFS selector further improved the efficiency of the recognition system with substantially lowered feature dimensions and elevated recognition rate. 相似文献
988.
989.
Zeeshan Pervez Asad Masood Khattak Sungyoung Lee Young-Koo Lee 《The Journal of supercomputing》2012,62(1):431-460
This paper addresses the issue of data governance in a cloud-based storage system. To achieve fine-grained access control over the outsourced data, we propose Self-Healing Attribute-based Privacy Aware Data Sharing in Cloud (SAPDS). The proposed system delegates the key distribution and management process to a cloud server without seeping out any confidential information. It facilitates data owner to restrain access of the user with whom data has been shared. User revocation is achieved by merely changing one attribute associated with the decryption policy, instead of modifying the entire access control policy. It enables authorized users to update their decryption keys followed by each user revocation, making it self-healing, without ever interacting with the data owner. Computation analysis of the proposed system shows that data owner can revoke n′ users with the complexity of O(n′). Besides this, legitimate users can update their decryption keys with the complexity of O(1). 相似文献
990.
Proactive thermal management in green datacenters 总被引:1,自引:1,他引:0
Eun Kyung Lee Indraneel Kulkarni Dario Pompili Manish Parashar 《The Journal of supercomputing》2012,60(2):165-195
The increasing demand for faster computing and high storage capacity has resulted in an increase in energy consumption and
heat generation in datacenters. Because of the increase in heat generation, cooling requirements have become a critical concern,
both in terms of growing operating costs as well as their environmental and societal impacts. Presently, thermal management
techniques make an effort to thermally profile and control datacenters’ cooling equipment to increase their efficiency. In
conventional thermal management techniques, cooling systems are triggered by the temperature crossing predefined thresholds.
Such reactive approaches result in delayed response as the temperature may already be too high, which can result in performance
degradation of hardware. 相似文献