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101.
We propose a system that allows the user to design a continuous flow animation starting from a still fluid image. The basic idea is to apply the fluid motion extracted from a video example to the target image. The system first decomposes the video example into three components, an average image, a flow field and residuals. The user then specifies equivalent information over the target image. The user manually paints the rough flow field, and the system automatically refines it using the estimated gradients of the target image. The user semi-automatically transfers the residuals onto the target image. The system then approximates the average image and synthesizes an animation on the target image by adding the transferred residuals and warping them according to the user-specified flow field. Finally, the system adjusts the appearance of the resulting animation by applying histogram matching. We designed animations of various pictures, such as rivers, waterfalls, fires, and smoke. 相似文献
102.
Tiago?OliveiraEmail author Ken?Satoh Paulo?Novais José?Neves Hiroshi?Hosobe 《Autonomous Agents and Multi-Agent Systems》2017,31(3):656-695
In this work a default revision mechanism is introduced into speculative computation to manage incomplete information. The default revision is supported by a method for the generation of default constraints based on Bayesian networks. The method enables the generation of an initial set of defaults which is used to produce the most likely scenarios during the computation, represented by active processes. As facts arrive, the Bayesian network is used to derive new defaults. The objective with such a new dynamic mechanism is to keep the active processes coherent with arrived facts. This is achieved by changing the initial set of default constraints during the reasoning process in speculative computation. A practical example in clinical decision support is described. 相似文献
103.
104.
Jorge Lopez-Moreno Jorge JimenezSunil Hadap Ken AnjyoErik Reinhard Diego Gutierrez 《Computers & Graphics》2011,35(1):99-111
Recent works in image editing are opening up new possibilities to manipulate and enhance input images. Within this context, we leverage well-known characteristics of human perception along with a simple depth approximation algorithm to generate non-photorealistic renditions that would be difficult to achieve with existing methods. Once a perceptually plausible depth map is obtained from the input image, we show how simple algorithms yield powerful new depictions of such an image. Additionally, we show how artistic manipulation of depth maps can be used to create novel non-photorealistic versions, for which we provide the user with an intuitive interface. Our real-time implementation on graphics hardware allows the user to efficiently explore artistic possibilities for each image. We show results produced with six different styles proving the versatility of our approach, and validate our assumptions and simplifications by means of a user study. 相似文献
105.
In a mobile environment, querying a database at a stationary server from a mobile client is expensive due to the limited
bandwidth of a wireless channel and the instability of the wireless network. We address this problem by maintaining a materialized
view in a mobile client's local storage. Such a materialized view can be considered as a data warehouse. The materialized
view contains results of common queries in which the mobile client is interested. In this paper, we address the view update
problem for maintaining the consistency between a materialized view at a mobile client and the database server. The content
of a materialized view could become incoherent with that at the database server when the content of the database server and/or
when the location of the client is changed. Existing view update mechanisms are ‘push-based’. The server is responsible for
notifying all clients whose views might be affected by the changes in database or the mobility of the client. This is not
appropriate in a mobile environment due to the frequent wireless channel disconnection. Furthermore, it is not easy for a
server to keep track of client movements to update individual client location-dependent views. We propose a ‘pull-based’ approach
that allows a materialized view to be updated at a client in an incremental manner, requiring a client to request changes
to its view from the server. We demonstrate the feasibility of our approach with experimental results.
Received 27 January 1999 / Revised 26 November 1999 / Accepted 17 April 2000 相似文献
106.
Len Seligman Paul Lehner Ken Smith Chris Elsaesser David Mattox 《Journal of Intelligent Information Systems》2000,14(1):29-50
We are interested in information management for decision support applications, especially those that monitor distributed, heterogeneous databases to assess time-critical decisions. Users of such applications can easily be overwhelmed with data that may change rapidly, may conflict, and may be redundant. Developers are faced with a dilemma: either filter out most information and risk excluding critical items, or gather possibly irrelevant or redundant information, and overwhelm the decision maker. This paper describes a solution to this dilemma called decision-centric information monitoring (DCIM). First, we observe that decision support systems should monitor only information that can potentially change some decision. We present an architecture for DCIM that meets the requirements implied by this observation. We describe techniques for identifying the highest value information to monitor and techniques for monitoring that information despite autonomy, distribution, and heterogeneity of data sources. Finally, we present lessons learned from building LOOKOUT, which is to our knowledge the first implementation of a top-to-bottom system performing decision-centric information monitoring. 相似文献
107.
Replica Placement Strategies in Data Grid 总被引:1,自引:0,他引:1
Replication is a technique used in Data Grid environments that helps to reduce access latency and network bandwidth utilization.
Replication also increases data availability thereby enhancing system reliability. The research addresses the problem of replication
in Data Grid environment by investigating a set of highly decentralized dynamic replica placement algorithms. Replica placement
algorithms are based on heuristics that consider both network latency and user requests to select the best candidate sites
to place replicas. Due to dynamic nature of Grid, the candidate site holds replicas currently may not be the best sites to
fetch replicas in subsequent periods. Therefore, a replica maintenance algorithm is proposed to relocate replicas to different
sites if the performance metric degrades significantly. The study of our replica placement algorithms is carried out using
a model of the EU Data Grid Testbed 1 [Bell et al. Comput. Appl., 17(4), 2003] sites and their associated network geometry. We validate our replica placement
algorithms with total file transfer times, the number of local file accesses, and the number of remote file accesses. 相似文献
108.
Evans WJ Yoo CS Lee GW Cynn H Lipp MJ Visbeck K 《The Review of scientific instruments》2007,78(7):073904
We have developed a unique device, a dynamic diamond anvil cell (dDAC), which repetitively applies a time-dependent load/pressure profile to a sample. This capability allows studies of the kinetics of phase transitions and metastable phases at compression (strain) rates of up to 500 GPa/s (approximately 0.16 s(-1) for a metal). Our approach adapts electromechanical piezoelectric actuators to a conventional diamond anvil cell design, which enables precise specification and control of a time-dependent applied load/pressure. Existing DAC instrumentation and experimental techniques are easily adapted to the dDAC to measure the properties of a sample under the varying load/pressure conditions. This capability addresses the sparsely studied regime of dynamic phenomena between static research (diamond anvil cells and large volume presses) and dynamic shock-driven experiments (gas guns, explosive, and laser shock). We present an overview of a variety of experimental measurements that can be made with this device. 相似文献
109.
Armstrong MR Boyden K Browning ND Campbell GH Colvin JD DeHope WJ Frank AM Gibson DJ Hartemann F Kim JS King WE LaGrange TB Pyke BJ Reed BW Shuttlesworth RM Stuart BC Torralva BR 《Ultramicroscopy》2007,107(4-5):356-367
Although recent years have seen significant advances in the spatial resolution possible in the transmission electron microscope (TEM), the temporal resolution of most microscopes is limited to video rate at best. This lack of temporal resolution means that our understanding of dynamic processes in materials is extremely limited. High temporal resolution in the TEM can be achieved, however, by replacing the normal thermionic or field emission source with a photoemission source. In this case the temporal resolution is limited only by the ability to create a short pulse of photoexcited electrons in the source, and this can be as short as a few femtoseconds. The operation of the photo-emission source and the control of the subsequent pulse of electrons (containing as many as 5 x 10(7) electrons) create significant challenges for a standard microscope column that is designed to operate with a single electron in the column at any one time. In this paper, the generation and control of electron pulses in the TEM to obtain a temporal resolution <10(-6)s will be described and the effect of the pulse duration and current density on the spatial resolution of the instrument will be examined. The potential of these levels of temporal and spatial resolution for the study of dynamic materials processes will also be discussed. 相似文献
110.
Ken Maynard Patrick Moss Marcus Whitehead S. Narayanan Matt Garay Nathan Brannon Raj Gopal Kantamneni & Todd Kustra 《Expert Systems》2001,18(2):88-98
Although developments on software agents have led to useful applications in automation of routine tasks such as electronic mail filtering, there is a scarcity of research that empirically evaluates the performance of a software agent versus that of a human reasoner, whose problem-solving capabilities the agent embodies. In the context of a game of a chance, namely Yahtzee©, we identified strategies deployed by expert human reasoners and developed a decision tree for agent development. This paper describes the computer implementation of the Yahtzee game as well as the software agent. It also presents a comparison of the performance of humans versus an automated agent. Results indicate that, in this context, the software agent embodies human expertise at a high level of fidelity. 相似文献