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991.
Scalable search-based image annotation 总被引:4,自引:0,他引:4
With the popularity of digital cameras, more and more people have accumulated considerable digital images on their personal
devices. As a result, there are increasing needs to effectively search these personal images. Automatic image annotation may
serve the goal, for the annotated keywords could facilitate the search processes. Although many image annotation methods have
been proposed in recent years, their effectiveness on arbitrary personal images is constrained by their limited scalability,
i.e. limited lexicon of small-scale training set. To be scalable, we propose a search-based image annotation algorithm that
is analogous to information retrieval. First, content-based image retrieval technology is used to retrieve a set of visually
similar images from a large-scale Web image set. Second, a text-based keyword search technique is used to obtain a ranked
list of candidate annotations for each retrieved image. Third, a fusion algorithm is used to combine the ranked lists into
a final candidate annotation list. Finally, the candidate annotations are re-ranked using Random Walk with Restarts and only
the top ones are reserved as the final annotations. The application of both efficient search techniques and Web-scale image
set guarantees the scalability of the proposed algorithm. Moreover, we provide an annotation rejection scheme to point out
the images that our annotation system cannot handle well. Experimental results on U. Washington dataset show not only the
effectiveness and efficiency of the proposed algorithm but also the advantage of image retrieval using annotation results
over that using visual features. 相似文献
992.
Image preview is a convenient way to browse large or multiple images on small displays. However, current signal-level image
resampling algorithms may remove many features of interest in the preview image. In this paper, we propose perceptual image
preview which retains more perceptual features such that users can inspect features of interest by viewing the preview image
only and without zooming in. This technology has two components, structure enhancement and perceptual feature visualization.
Structure enhancement enhances the image structure while suppressing subtle details using a gradient modulation method, thus
making the succedent perceptual features more apparent. For perceptual feature visualization, features of interest detected
in the picture is visualized on the structure enhanced preview image. We demonstrate with two examples of most commonly used image quality features, image blur and noise. The effectiveness of the proposed method is validated
by experimental results. 相似文献
993.
Kui Liu Wei-zheng Yuan Jin-jun Deng Bing-he Ma Cheng-yu Jiang 《Microsystem Technologies》2008,14(1):1-6
Microelectromechanical systems plays an important role for studying gaseous or liquid fluid flows experimentally due to the
dimensions of the device on the μm-scale. For aerodynamic applications, the detection of the location of the separation point
of the boundary layer is very important, which is used for active flow control and smart skin adaptive control system. This
paper presents the design and integration methods of a flexible polymide substrate micro thermal sensor array, sensor array
driver circuit, dynamic data acquisition circuit, and criterion algorithm of the boundary layer separation point. The above
algorithms were used to analyze the NACA0012 wind tunnel test data at flow conditions of the velocity 40 m/s and AOA 16°.
The result demonstrated the above system can fulfill the dynamic and real-time of the adaptive control system. 相似文献
994.
Stella Clarke Gerhard Schillhuber Michael F. Zaeh Heinz Ulbrich 《Multimedia Systems》2008,13(4):253-261
The remote nature of telepresence scenarios can be seen as a strongpoint and also as a weakness. Although it enables the remote
control of robots in dangerous or inaccessible environments, it necessarily involves some kind of communication mechanism
for the transmission of control signals. This communication mechanism necessarily involves adverse network effects such as
delay. Three mechanisms aimed at improving the effects of network delay are presented in this paper: (1) Motion prediction
to partially compensate for network delays, (2) force prediction to learn a local force model, thereby reducing dependency
on delayed force signals, and (3) haptic data compression to reduce the required bandwidth of high frequency data. The utilized
motion prediction scheme was shown to improve operator performance, but had no influence on operator immersion. The force
prediction provided haptic feedback through synchronous forces from the local model, thereby stabilizing the control loop.
The developed haptic data compression scheme reduced the number of packets sent across the network by 90%, while improving
the quality of the haptic feedback. 相似文献
995.
Wang-Long Li 《Microsystem Technologies》2008,14(3):315-324
The squeeze film behavior of MEMS torsion mirrors is modeled, analyzed and discussed. Effects of gas rarefaction (first-order
slip-flow model with non-symmetric accommodation coefficients, ACs) and surface roughness are considered simultaneously by
using the average Reynolds type equation (ARTE). Based on the operating conditions with small variations in film thickness
and pressure, the ARTE is linearized. A coordinate transformation, by stretching or contracting the axes by referring to the
roughness flow factors, is proposed to transform the linearized ARTE into a diffusion type modal equation. The dynamic coefficients
(stiffness and damping coefficients) are then derived and expressed in analytical form. The results show that the tilting
frequency (or Γ0 squeeze number), roughness parameters (γ Peklenik numbers, σ standard deviation of composite roughness) and gas rarefaction
parameters (D inverse Knudsen number, ACs) are all important parameters on analyzing the dynamic performance of MEMS torsion mirrors. 相似文献
996.
Vassilis Agouridas Alison McKay Henri Winand Alan de Pennington 《Requirements Engineering》2008,13(1):19-48
This paper reports results of research into the definition of requirements for new consumer products––specifically, electro-mechanical
products. The research dealt with the derivation of design requirements that are demonstrably aligned with stakeholder needs.
The paper describes a comprehensive process that can enable product development teams to deal with statements of product requirements,
as originally collected through market research activities, in a systematic and traceable manner from the early, fuzzy front
end, stages of the design process. The process described has been based on principles of systems engineering. A case study
from its application and evaluation drawn from the power sector is described in this paper. The case study demonstrates how
the process can significantly improve product quality planning practices through revision of captured product requirements,
analysis of stakeholder requirements and derivation of design requirements. The paper discusses benefits and issues from the
use of the process by product development teams, and identifies areas for further research. Finally, the conclusions drawn
from the reported research are presented.
相似文献
Vassilis AgouridasEmail: |
997.
A case study validation of a knowledge-based approach for the selection of requirements engineering techniques 总被引:2,自引:1,他引:1
Requirements engineering (RE) is a critical phase in the software engineering process and plays a vital role in ensuring the
overall quality of a software product. Recent research has shown that industry increasingly recognizes the importance of good
RE practices and the use of appropriate RE techniques. However, due to the large number of RE techniques, requirements engineers
find it challenging to select suitable techniques for a particular project. Unfortunately, technique selection based on personal
experience has limitations with regards to the scope, effectiveness and suitability of the RE techniques for the project at
hand. In this paper, a Knowledge-based Approach for the Selection of Requirements Engineering Techniques (KASRET) is proposed
that helps during RE techniques selection. This approach has three major features. First, a library of requirements techniques
was developed which includes detailed knowledge about RE techniques. Second, KASRET integrates advantages of different knowledge
representation schemata and reasoning mechanisms. Thus, KASRET provides mechanisms for the management of knowledge about requirements
techniques and support for RE process development. Third, as a major decision support mechanism, an objective function evaluates
the overall ability and cost of RE techniques, which is helpful for the selection of RE techniques. This paper makes not only
a contribution to RE but also to research and application of knowledge management and decision support in process development.
A case study using an industrial project shows the support of KASRET for RE techniques selection.
相似文献
Behrouz H. FarEmail: |
998.
999.
Satinder P. Gill 《AI & Society》2008,22(3):283-300
Socio-ethics covers the relation of the individual with the group and with society, as the individual acquires the skills
for social life with others and the conduct of ‘normal responsible behaviour’ (Leal in AI Soc 9:29–32, 1995) that guides moral action. For a consideration of what it means to be socially skilled in everyday human interaction and
the ethical issues arising from the new conditions of interaction that come with the integration of intelligent interactive
artefacts, we will provide an analysis at multiple levels of these phenomena and draw on a variety of application domains,
for example, healthcare and interactive media. 相似文献
1000.
David J. Calverley 《AI & Society》2008,22(4):523-537
As non-biological machines come to be designed in ways which exhibit characteristics comparable to human mental states, the
manner in which the law treats these entities will become increasingly important both to designers and to society at large.
The direct question will become whether, given certain attributes, a non-biological machine could ever be viewed as a “legal
person.” In order to begin to understand the ramifications of this question, this paper starts by exploring the distinction
between the related concepts of “human,” “person,” and “property.” Once it is understood that person in the legal sense can
apply to a non-biological entity such as a corporation, the inquiry then goes on to examine the folk psychology view of intentionality
and the concept of autonomy. The conclusion reached is that these two attributes can support the view that a non-biological
machine, at least in theory, can be viewed as a legal person.
相似文献
David J. CalverleyEmail: |