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991.
Lee Cha DiVerdi Stephen H llerer Tobias 《IEEE transactions on visualization and computer graphics》2009,15(1):20-33
We present an immaterial display that uses a generalized form of depth-fused 3D (DFD) rendering to create unencumbered 3D visuals. To accomplish this result, we demonstrate a DFD display simulator that extends the established depth-fused 3D principle by using screens in arbitrary configurations and from arbitrary viewpoints. The feasibility of the generalized DFD effect is established with a user study using the simulator. Based on these results, we developed a prototype display using one or two immaterial screens to create an unencumbered 3D visual that users can penetrate, examining the potential for direct walk-through and reach-through manipulation of the 3D scene. We evaluate the prototype system in formative and summative user studies and report the tolerance thresholds discovered for both tracking and projector errors. 相似文献
992.
Lee Taehee H llerer Tobias 《IEEE transactions on visualization and computer graphics》2009,15(3):355-368
We describe a novel markerless camera tracking approach and user interaction methodology for augmented reality (AR) on unprepared tabletop environments. We propose a real-time system architecture that combines two types of feature tracking. Distinctive image features of the scene are detected and tracked frame-to-frame by computing optical flow. In order to achieve real-time performance, multiple operations are processed in a synchronized multi-threaded manner: capturing a video frame, tracking features using optical flow, detecting distinctive invariant features, and rendering an output frame. We also introduce user interaction methodology for establishing a global coordinate system and for placing virtual objects in the AR environment by tracking a user's outstretched hand and estimating a camera pose relative to it. We evaluate the speed and accuracy of our hybrid feature tracking approach, and demonstrate a proof-of-concept application for enabling AR in unprepared tabletop environments, using bare hands for interaction. 相似文献
993.
Choe Sungyul Kim Junho Lee Haeyoung Lee Seungyong 《IEEE transactions on visualization and computer graphics》2009,15(1):160-173
Previous mesh compression techniques provide decent properties such as high compression ratio, progressive decoding, and out-of-core processing. However, only a few of them supports the random accessibility in decoding, which enables the details of any specific part to be available without decoding other parts. This paper proposes an effective framework for the random accessibility of mesh compression. The key component of the framework is a wire-net mesh constructed from a chartification of the given mesh. Charts are compressed separately for random access to mesh parts and a wire-net mesh provides an indexing and stitching structure for the compressed charts. Experimental results show that random accessibility can be achieved with competent compression ratio, which is only a little worse than single-rate and comparable to progressive encoding. To demonstrate the merits of the framework, we apply it to process huge meshes in an out-of-core manner, such as out-of-core rendering and out-of-core editing. 相似文献
994.
Soo-Yong Shin In-Hee Lee Young-Min Cho Kyung-Ae Yang Byoung-Tak Zhang 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2009,39(6):1606-1616
Probe design is one of the most important tasks in successful deoxyribonucleic acid microarray experiments. We propose a multiobjective evolutionary optimization method for oligonucleotide probe design based on the multiobjective nature of the probe design problem. The proposed multiobjective evolutionary approach has several distinguished features, compared with previous methods. First, the evolutionary approach can find better probe sets than existing simple filtering methods with fixed threshold values. Second, the multiobjective approach can easily incorporate the user's custom criteria or change the existing criteria. Third, our approach tries to optimize the combination of probes for the given set of genes, in contrast to other tools that independently search each gene for qualifying probes. Lastly, the multiobjective optimization method provides various sets of probe combinations, among which the user can choose, depending on the target application. The proposed method is implemented as a platform called EvoOligo and is available for service on the Web. We test the performance of EvoOligo by designing probe sets for 19 types of Human Papillomavirus and 52 genes in the Arabidopsis Calmodulin multigene family. The design results from EvoOligo are proven to be superior to those from well-known existing probe design tools, such as OligoArray and OligoWiz. 相似文献
995.
An extension of the Cauer ladder development for synthesizing singly terminated filters with symmetric and asymmetric responses is presented. Basically, a driving‐point immittance including reactive constant elements is carried out in such a way that provides the transmission zeros. The reactive constant elements are introduced into the synthesis for two reasons. The first is to consider the possibility of the asymmetric position of transmission zeros in the real frequency axis. The second one is to obtain canonical forms, i.e. networks with the minimum number of elements in the case of symmetrical responses. To validate the proposed method, a filter with asymmetrical response has been synthesized, comparing different topologies for its use in multiplexers. This fact is illustrated with a Ku‐band elliptic response diplexer designed in H‐plane rectangular waveguide. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009. 相似文献
996.
In a highly competitive market, customers' product affection is a critical factor to product success. However, understanding customers' affective needs is difficult to grasp; product design practitioners often misunderstand what customers really want. In this study we report our experience in developing and using an affective design framework that identified critical affective features customers have on products and are systematically incorporated into product design attributes. To identify key affective features such as luxuriousness, we utilized the Kansei engineering methodology. This approach consists of three steps: (1) selecting related affective features and product design attributes through a comprehensive literature survey, expert panel opinion, and focus group interviews; (2) conducting evaluation experiments; and (3) developing Kansei models using multivariate statistical analysis and analyzing critical product design attributes. To demonstrate applicability of the proposed affective design framework, 30 customers and 30 product design practitioners participated in an evaluation experiment for car crash pads, and 44 customers and 20 designers participated in an evaluation experiment for two interior room products (wallpapers and flooring materials). The evaluation experiments were conducted via systematically developed questionnaires consisting of a 7‐point semantic differential scale and a 100‐point magnitude estimation scale. The results of the experiments were analyzed using principal component regression and quantification theory type I method. Using the analyzed survey data, the relationship between luxuriousness and related affective features and product design attributes were identified. This relationship indicated that there was a significant difference in the perception of luxuriousness between customers and designers. Consequently, it is expected that the results of this study could provide a foundation for developing affective products. © 2009 Wiley Periodicals, Inc. 相似文献
997.
Hak-Man Kim Jong-Joo Lee Myong-Chul Shin Seok-Soo Kim 《Information Systems Frontiers》2009,11(5):523-528
For more efficient and economical management of substations under SCADA (Supervisory Control and Data Acquisition) systems, the concept of a smart substation has been introduced using intelligent and ubiquitous IT (Information Technology) techniques. A multi-functional platform needs to perform more intelligent and ubiquitous functions of smart substation effectively. In this paper, we propose a multi-functional platform to implement smart substations effectively. A prototype hardware, functions and communication interfaces on an embedded platform are introduced. Also, we suggest operating system architecture for smart substations. 相似文献
998.
Xiaonan Lu Saurabh Kataria William J. Brouwer James Z. Wang Prasenjit Mitra C. Lee Giles 《International Journal on Document Analysis and Recognition》2009,12(2):65-81
Authors use images to present a wide variety of important information in documents. For example, two-dimensional (2-D) plots
display important data in scientific publications. Often, end-users seek to extract this data and convert it into a machine-processible
form so that the data can be analyzed automatically or compared with other existing data. Existing document data extraction
tools are semi-automatic and require users to provide metadata and interactively extract the data. In this paper, we describe
a system that extracts data from documents fully automatically, completely eliminating the need for human intervention. The
system uses a supervised learning-based algorithm to classify figures in digital documents into five classes: photographs,
2-D plots, 3-D plots, diagrams, and others. Then, an integrated algorithm is used to extract numerical data from data points
and lines in the 2-D plot images along with the axes and their labels, the data symbols in the figure’s legend and their associated
labels. We demonstrate that the proposed system and its component algorithms are effective via an empirical evaluation. Our
data extraction system has the potential to be a vital component in high volume digital libraries. 相似文献
999.
As service robots and other ubiquitous technology have evolved, an increasing need for the autonomous navigation of mobile
objects has arisen. In a large number of localization schemes, the absolute-position estimation method, which relies on navigation
beacons or landmarks, has been widely used as it has the advantages of being economical and accurate. However, only a few
of these schemes have expanded their application to complicated workspaces, or those that have many rooms or blocks. As the
navigation of mobile objects in complicated workspaces is vital for ubiquitous technology, multiblock navigation is necessary.
This article presents methodologies and techniques for the multiblock navigation of the indoor localization system with active
beacon sensors. This new indoor localization system design includes ultrasonic attenuation compensation, dilution-of-precision
analysis, and a fault detection and isolation algorithm using redundant measurements.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
1000.
Yau-Zen Chang Jung-Fu Hou Yung-Pyng Chang Shih-Tseng Lee 《Artificial Life and Robotics》2009,14(2):228-232
In this article, we investigate the problem of integrating a binocular stereo vision system and a laser range finder to construct
a 3-D map of the environment. The proposed scheme is realized by using the alignment parameters obtained in the 2-D map construction
of the laser range finder for the 3-D data generated by the stereo vision system. The 2-D map alignment task is formulated
as an optimization problem of minimizing the alignment errors between local maps and selected parts of the developing global
map. The problem is then solved using the Simplex method. To increase the robustness of the searching process, multiple initial
guesses are provided in the Simplex method. The performance of the proposed architecture is verified by experimental results
from a mobile vehicle for obstacle avoidance. 相似文献