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941.
Adaptive Hypermedia 总被引:9,自引:2,他引:7
Adaptive hypermedia is a relatively new direction of research on the crossroads of hypermedia and user modeling. Adaptive hypermedia systems build a model of the goals, preferences and knowledge of each individual user, and use this model throughout the interaction with the user, in order to adapt to the needs of that user. The goal of this paper is to present the state of the art in adaptive hypermedia at the eve of the year 2000, and to highlight some prospects for the future. This paper attempts to serve both the newcomers and the experts in the area of adaptive hypermedia by building on an earlier comprehensive review (Brusilovsky, 1996; Brusilovsky, 1998). 相似文献
942.
Evolutionary Learning of a Fuzzy Behavior Based Controller for a Nonholonomic Mobile Robot in a Class of Dynamic Environments 总被引:1,自引:0,他引:1
D. P. Thrishantha Nanayakkara Keigo Watanabe Kazuo Kiguchi Kiyotaka Izumi 《Journal of Intelligent and Robotic Systems》2001,32(3):255-277
This paper presents an approach for evolving optimum behaviors for a nonholonomic mobile robot in a class of dynamic environments. A new evolutionary algorithm reflecting some powerful features in the natural evolutionary process to have flexibility to deal with changes in the environment is used to evolve optimum behaviors. Furthermore, a fuzzy set based multi-objective fitness evaluation function is adopted in the evolutionary algorithm. The multi-objective evaluation function is designed so that it allows incorporating complex linguistic features that a human observer would desire in the behaviors of the mobile robot movements. To illustrate the effectiveness of the proposed method, simulation results are compared using a conventional evolutionary algorithm. 相似文献
943.
Agustin Ramirez-Agundis Rafael Gadea-Girones Ricardo Colom-Palero Javier Diaz-Carmona 《Journal of Real-Time Image Processing》2007,2(4):271-280
This paper presents a scheme and its Field Programmable Gate Array (FPGA) implementation for a system based on combining the
bi-dimensional discrete wavelet transformation (2D-DWT) and vector quantization (VQ) for image compression. The 2D-DWT works
in a non-separable fashion using a parallel filter structure with distributed control to compute two resolution levels. The
wavelet coefficients of the higher frequency sub-bands are vector quantized using multi-resolution codebook and those of the
lower frequency sub-band at level two are scalar quantized and entropy encoded. VQ is carried out by self organizing feature
map (SOFM) neural nets working at the recall phase. Codebooks are quickly generated off-line using the same nets functioning
at the training phase. The complete system, including the 2D-DWT, the multi-resolution codebook VQ, and the statistical encoder,
was implemented on a Xilinx Virtex 4 FPGA and is capable of performing real-time compression for digital video when dealing
with grayscale 512 × 512 pixels images. It offers high compression quality (PSNR values around 35 dB) and acceptable compression
rate values (0.62 bpp).
相似文献
Javier Diaz-CarmonaEmail: |
944.
945.
Coordination components for collaborative virtual environments 总被引:1,自引:0,他引:1
Alberto B. Raposo Adailton J. A. da Cruz Christian M. Adriano Lo P. Magalhes 《Computers & Graphics》2001,25(6):1025-1039
This paper deals with the behavior of virtual environments from the collaboration point-of-view, in which actors (human or virtual beings) interact and collaborate by means of interdependent tasks. In this sense, actors may realize tasks that are dependent on tasks performed by other actors, while the interdependencies between tasks (through resource management and temporal relations) delineate the overall behavior of a virtual environment. Our main goal is to propose an approach for the coordination of those behaviors. Initially a generic study of possible interdependencies between collaborative tasks is presented, followed by the formal modeling (using Petri Nets) of coordination mechanisms for those dependencies. In order to implement such mechanisms, an architecture of reusable and pluggable coordination components is also introduced. These components are used in an implementation of a multi-user videogame. The presented approach is a concrete step to create virtual societies of actors that collaborate to reach common goals without the risk of getting involved in conflicting or repetitive tasks. 相似文献
946.
Jeffrey Kotula 《Software》2001,31(12):1131-1142
Typical software companies want the applications they market to have a consistent look and feel, so as to brand or identify their particular family of products or product line. Current user interface (UI) implementation techniques serve this business need poorly, tending to treat each application as a unique, independent artifact sharing little, if any, UI implementation code with other applications. Coupled with the overwhelming complexity found in modern UI toolkits, this results in unnecessarily high development costs for interfaces, and is at odds with the need of software companies to devote their resources to value‐added application code rather than incidental user‐interface implementation. This paper presents a model for a domain‐based UI application framework that addresses these issues: consistency in a family of products, both in operation and presentation; reduced implementation costs; and rapid development times. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
947.
Information retrieval from the World Wide Web through the use of search engines is known to be unable to capture effectively
the information needs of users. The approach taken in this paper is to add intelligence to information retrieval from the
World Wide Web, by the modeling of users to improve the interaction between the user and information retrieval systems. In
other words, to improve the performance of the user in retrieving information from the information source. To effect such
an improvement, it is necessary that any retrieval system should somehow make inferences concerning the information the user
might want. The system then can aid the user, for instance by giving suggestions or by adapting any query based on predictions
furnished by the model. So, by a combination of user modeling and fuzzy logic a prototype system has been developed (the Fuzzy
Modeling Query Assistant (FMQA)) which modifies a user's query based on a fuzzy user model. The FMQA was tested via a user
study which clearly indicated that, for the limited domain chosen, the modified queries are better than those that are left
unmodified.
Received 10 November 1998 / Revised 14 June 2000 / Accepted in revised form 25 September 2000 相似文献
948.
陈慧南 《计算机工程与科学》2000,22(1):89-91
本文讨论基于扩充的着色网的事件驱动用户界面规范的实例问题。我们使用扩充的着色网作为对话模型表达互软件的人机交互行为。文中简述了扩充的着色网对话模型,给出 其对象一联系模型及核心算法,最后给出产将扩充的着色网表达的事件驱动用户界面规范转换成可视编程环境的语言程序的方法。 相似文献
949.
叶瑞松 《计算机工程与科学》2000,22(2):28-29
由迭代函数系统可以产生地毯图案 ,这是由于迭代函数系统的随机性选择能产生分形图形。本文从不同的角度 ,利用确定的简单数学模型二维函数 Henon映射所特有的动力系统混沌性质生成了地毯图案。 相似文献
950.
José Maurício S. Bento Terezinha M. C. Della Lucia Rosa T. S. Frighetto 《Journal of chemical ecology》1993,19(10):2347-2351
Males of the sugarcane borer,Migdolus fryanus (Coleoptera: Cerambycidae), are attracted to females by means of a sex pheromone. Mating usually occurs during a few days from October to March under field conditions in São Paulo State, Brazil. This work reports on mating of this species as affected by daily climatic factors, during a single nuptial flight. Maximum male capture by the natural sex pheromone occurred from 1000 to 1100 AM at air and soil temperatures of 30.0°C and relative humidity of 57.0%. As these temperatures increased, females burrowed into the soil, as they are more sensitive to heat than males. Thus, it was concluded that sex pheromone-mediated mating in this cerambycid is directly affected by temperatures of air and soil. 相似文献