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排序方式: 共有1464条查询结果,搜索用时 15 毫秒
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This study aimed to investigate the mechanical properties of concrete containing solid–liquid phase-change material (PCM) and focused on two key factors. First, a systematic study on the mechanical performance of PCM-modified concretes was conducted, including compressive, elastic modulus, and shrinkage tests. Second, because PCM provides high latent heat during the solid–liquid phase change, the effects of the solid phase and liquid phase on the mechanical properties of concrete were also explored. Results of this study showed that the solid–liquid phase of PCM affected the mechanical properties of concrete. For example, the compressive strength of 10% PCM concrete in solid phase (23 °C) and liquid phase (40 °C) at 28 days was 29.30 and 19.57 MPa, respectively. In addition, with increasing PCM content, the mechanical properties were degraded. For example, 10, 20, and 30% of PCM content lowered the compressive strength by 35.4, 58.4, and 74.3%, respectively. Therefore, concrete with PCM may not be suitable for structural elements. However, PCM is an important solution for optimizing energy consumption in modern buildings. It can absorb or emit large amounts of heat to store or release thermal energy. These properties can be used to control building temperatures resulting in energy saving and carbon reduction. 相似文献
23.
Feature Tracking with Automatic Selection of Spatial Scales 总被引:1,自引:0,他引:1
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Tony Tan 《Journal of Computer and System Sciences》2010,76(8):778-791
In this paper we study a subclass of pebble automata (PA) for data languages for which the emptiness problem is decidable. Namely, we show that the emptiness problem for weak 2-pebble automata is decidable, while the same problem for weak 3-pebble automata is undecidable. We also introduce the so-called top view weak PA. Roughly speaking, top view weak PA are weak PA where the equality test is performed only between the data values seen by the two most recently placed pebbles. The emptiness problem for this model is still decidable. It is also robust: alternating, non-deterministic and deterministic top view weak PA have the same recognition power; and are strong enough to accept all data languages expressible in Linear Temporal Logic with the future-time operators, augmented with one register freeze quantifier. 相似文献
25.
One of the main goals of an applied research field such as software engineering is the transfer and widespread use of research
results in industry. To impact industry, researchers developing technologies in academia need to provide tangible evidence
of the advantages of using them. This can be done trough step-wise validation, enabling researchers to gradually test and
evaluate technologies to finally try them in real settings with real users and applications. The evidence obtained, together
with detailed information on how the validation was conducted, offers rich decision support material for industry practitioners
seeking to adopt new technologies and researchers looking for an empirical basis on which to build new or refined technologies.
This paper presents model for evaluating the rigor and industrial relevance of technology evaluations in software engineering.
The model is applied and validated in a comprehensive systematic literature review of evaluations of requirements engineering
technologies published in software engineering journals. The aim is to show the applicability of the model and to characterize
how evaluations are carried out and reported to evaluate the state-of-research. The review shows that the model can be applied
to characterize evaluations in requirements engineering. The findings from applying the model also show that the majority
of technology evaluations in requirements engineering lack both industrial relevance and rigor. In addition, the research
field does not show any improvements in terms of industrial relevance over time. 相似文献
26.
Charles W. Fox Ben Mitchinson Martin J. Pearson Anthony G. Pipe Tony J. Prescott 《Autonomous Robots》2009,26(4):223-239
Actuated artificial whiskers modeled on rat macrovibrissae can provide effective tactile sensor systems for autonomous robots.
This article focuses on texture classification using artificial whiskers and addresses a limitation of previous studies, namely,
their use of whisker deflection signals obtained under relatively constrained experimental conditions. Here we consider the
classification of signals obtained from a whiskered robot required to explore different surface textures from a range of orientations
and distances. This procedure resulted in a variety of deflection signals for any given texture. Using a standard Gaussian
classifier we show, using both hand-picked features and ones derived from studies of rat vibrissal processing, that a robust
rough-smooth discrimination is achievable without any knowledge of how the whisker interacts with the investigated object.
On the other hand, finer discriminations appear to require knowledge of the target’s relative position and/or of the manner
in which the whisker contact its surface.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users.
相似文献
Anthony G. Pipe |
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Stefan Mairhofer James Johnson Craig J. Sturrock Malcolm J. Bennett Sacha J. Mooney Tony P. Pridmore 《Machine Vision and Applications》2016,27(5):721-734
We propose a visual object tracking framework for the extraction of multiple interacting plant root systems from three-dimensional X-ray micro computed tomography images of plants grown in soil. Our method is based on a level set framework guided by a greyscale intensity distribution model to identify object boundaries in image cross-sections. Root objects are followed through the data volume, while updating the tracker’s appearance models to adapt to changing intensity values. In the presence of multiple root systems, multiple trackers can be used, but need to distinguish target objects from one another in order to correctly associate roots with their originating plants. Since root objects are expected to exhibit similar greyscale intensity distributions, shape information is used to constrain the evolving level set interfaces in order to lock trackers to their correct targets. The proposed method is tested on root systems of wheat plants grown in soil. 相似文献
30.
Crusta: A new virtual globe for real-time visualization of sub-meter digital topography at planetary scales 总被引:1,自引:0,他引:1
Tony Bernardin Eric CowgillOliver Kreylos Christopher BowlesPeter Gold Bernd HamannLouise Kellogg 《Computers & Geosciences》2011,37(1):75-85
Virtual globes are becoming ubiquitous in the visualization of planetary bodies and Earth specifically. While many of the current virtual globes have proven to be quite useful for remote geologic investigation, they were never designed for the purpose of serving as virtual geologic instruments. Their shortcomings have become more obvious as earth scientists struggle to visualize recently released digital elevation models of very high spatial resolution (0.5-1 m2/sample) and extent (>2000 km2). We developed Crusta as an alternative virtual globe that allows users to easily visualize their custom imagery and more importantly their custom topography. Crusta represents the globe as a 30-sided polyhedron to avoid distortion of the display, in particular the singularities at the poles characteristic of other projections. This polyhedron defines 30 “base patches,” each being a four-sided region that can be subdivided to an arbitrarily fine grid on the surface of the globe to accommodate input data of arbitrary resolution, from global (BlueMarble) to local (tripod LiDAR), all in the same visualization. We designed Crusta to be dynamic with the shading of the terrain surface computed on-the-fly when a user manipulates his point-of-view. In a similarly interactive fashion the globe's surface can be exaggerated vertically. The combination of the two effects greatly improves the perception of shape. A convenient pre-processing tool based on the GDAL library facilitates importing a number of data formats into the Crusta-specific multi-scale hierarchies that enable interactive visualization on a range of platforms from laptops to immersive geowalls and caves. The main scientific user community for Crusta is earth scientists, and their needs have been driving the development. 相似文献