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991.
本文给出了蜜罐和蜜网的定义及分类,介绍了蜜罐的主要技术原理,并且比较和分析了第一代和第二代蜜网模型。 相似文献
992.
80C51原始IP核内部RAM的扩展方案 总被引:2,自引:0,他引:2
80C51系列单片机是一类经典的8位微处理器,其设计方法和体系结构一直是其他各类单片机设计的参考典范,自从20世纪80年代面世以后,得到了极大的发展与应用。直到今天,市场上还有一大部分单片机应用成品将其作为处理核心。基于80C51系列单片机无知识产权保护、市场应用广泛等优点,对其进行功能拓展,既有利于经济上节约成本,也有利于成果的推广使用。 相似文献
993.
Wen Song Xiaohua Li Yuning Zhang Yike Qi Xiaowei Yang 《Journal of the Society for Information Display》2008,16(5):587-593
Abstract— In this paper, several methods to characterize motion blur on liquid‐crystal displays are reviewed. Based on the assumptions of smooth‐pursuit eye tracking and one‐frame temporal luminance integration, a simple algorithm has been proposed to calculate the normalized blurred edge width (N‐BEW) and motion‐picture response time (MPRT) with a one‐frame‐time moving‐window function to LC temporal step response curves. A custom measurement system with a fast‐eye‐sensitivity‐compensated photodiode has been developed to characterize motion blur based on LC response curves (LCRCs). MPRT values obtained by using the algorithm mentioned above and those from the smooth‐pursuit‐camera methods agree. Perception experiments were conducted to validate the correspondence between the simulated results and actual perceived images by the human eyes. In addition, the insufficiency of MPRT to evaluate motion blur on impulse‐type light‐generation LCDs, by analyzing the measurement results of a scanning backlight LCD, is discussed. 相似文献
994.
Wen Gao Bo Cao Shiguang Shan Xilin Chen Delong Zhou Xiaohua Zhang Debin Zhao 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2008,38(1):149-161
In this paper, we describe the acquisition and contents of a large-scale Chinese face database: the CAS-PEAL face database. The goals of creating the CAS-PEAL face database include the following: 1) providing the worldwide researchers of face recognition with different sources of variations, particularly pose, expression, accessories, and lighting (PEAL), and exhaustive ground-truth information in one uniform database; 2) advancing the state-of-the-art face recognition technologies aiming at practical applications by using off-the-shelf imaging equipment and by designing normal face variations in the database; and 3) providing a large-scale face database of Mongolian. Currently, the CAS-PEAL face database contains 99 594 images of 1040 individuals (595 males and 445 females). A total of nine cameras are mounted horizontally on an arc arm to simultaneously capture images across different poses. Each subject is asked to look straight ahead, up, and down to obtain 27 images in three shots. Five facial expressions, six accessories, and 15 lighting changes are also included in the database. A selected subset of the database (CAS-PEAL-R1, containing 30 863 images of the 1040 subjects) is available to other researchers now. We discuss the evaluation protocol based on the CAS-PEAL-R1 database and present the performance of four algorithms as a baseline to do the following: 1) elementarily assess the difficulty of the database for face recognition algorithms; 2) preference evaluation results for researchers using the database; and 3) identify the strengths and weaknesses of the commonly used algorithms. 相似文献
995.
This paper demonstrates a haptic device for interaction with a virtual environment. The force control is added by visual feedback
that makes the system more responsive and accurate. There are two popular control methods widely used in haptic controller
design. First, is impedance control when user motion input is measured, and then, the reaction force is fed back to the operator.
The alternative method is admittance control, when forces exerted by user are measured and motion is fed back to the user.
Both, impedance and admittance control are also basic ways for interacting with a virtual environment. In this paper, several
experiments were performed to evaluate the suitability of force-impedance control for haptic interface development. The difference
between conventional application of impedance control in robot motion control and its application in haptic interface development
is investigated. Open loop impedance control methodology is implemented for static case and a general-purpose robot under
open loop impedance control was developed as a haptic device, while a closed loop model based impedance control was used for
haptic controller design in both static and dynamic case. The factors that could affect to the performance of a haptic interface
are also investigated experimentally using parametric studies. Experimental results for 1 DOF rotational motion and 2 DOF
planar translational motion systems are presented. The results show that the impedance control aided by visual feedback broaden
the applicability of the haptic device and makes the system more responsive and accurate.
相似文献
J. SasiadekEmail: |
996.
对组合电路的测试提出了一种将确定性测试生成方法与内建自测试相结合的设计方案;设计实现了利用D算法生成的测试矢量和伪随机测试序列生成电路共同构成测试矢量生成模块,利用内建自测试方法完成可测性设计,并将两者结合得出组合电路内建自测试的改进方法;分析与实验结果表明,该方法能减少系统硬件占用,同时具有测试向量少、故障覆盖率高的特点。 相似文献
997.
毛文 《数码设计:surface》2008,(10):46-48
文字是电视节目包装中的重要元素之一,除了传达信息的基本功能之外,经常起到决定整体效果的关键作用。节目包装文字设计应突出本台文化和本土文化,文字的设计必须与节目相匹配,形成统一整体。 相似文献
998.
MPEG音频编码标准的实现算法比较复杂,而目前对该算法的优化大部分集中在在对算法的简化上,以减少运算量,在这方面已经有了很大的发展,通过从算法编码实现上,讨论对MP2编码算法的优化. 相似文献
999.
1000.
Jian WS Hsu CY Hao TH Wen HC Hsu MH Lee YL Li YC Chang P 《Computer methods and programs in biomedicine》2007,88(2):102-111
Traditional electronic health record (EHR) data are produced from various hospital information systems. They could not have existed independently without an information system until the incarnation of XML technology. The interoperability of a healthcare system can be divided into two dimensions: functional interoperability and semantic interoperability. Currently, no single EHR standard exists that provides complete EHR interoperability. In order to establish a national EHR standard, we developed a set of local EHR templates. The Taiwan Electronic Medical Record Template (TMT) is a standard that aims to achieve semantic interoperability in EHR exchanges nationally. The TMT architecture is basically composed of forms, components, sections, and elements. Data stored in the elements which can be referenced by the code set, data type, and narrative block. The TMT was established with the following requirements in mind: (1) transformable to international standards; (2) having a minimal impact on the existing healthcare system; (3) easy to implement and deploy, and (4) compliant with Taiwan's current laws and regulations. The TMT provides a basis for building a portable, interoperable information infrastructure for EHR exchange in Taiwan. 相似文献