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991.
基本矩阵作为分析两视图对极几何的有力工具,在视觉领域中占用重要的地位.分析了传统鲁棒方法在基本矩阵的求解问题中存在的不足,引入了稳健回归分析中的LQS方法,并结合Bucket分割技术,提出一种鲁棒估计基本矩阵的新方法,克服了RANSAC方法和LMedS方法的缺陷.模拟数据和真实图像实验结果表明,本文方法具有更高的鲁棒性和精确度. 相似文献
992.
章毓晋 《中国图象图形学报》2009,14(5):809-837
该文是关于中国图像工程的年度文献综述系列之十四。为了使国内广大从事图像工程研究和图像技术应用的科技人员能够较全面地了解国内图像工程研究和发展的现状,并能够方便地查询有关文献,现从2008年在国内15种有关图像工程重要中文期刊的共120期上发表的3 359篇学术研究和技术应用文献中,选取出915篇属于图像工程领域的文献,并根据各文献的主要内容将其分别归入图像处理,图像分析,图像理解,技术应用和综述5个大类,然后进一步分入23个专业小类(与去年相同)。在此基础上还进行了各期刊各类文献的统计和分析。根据统计分析结果可看到,我国图像工程在2008年许多新进展的情况。特别值得指出的是,在上述15种期刊上所发表的图像工程文献数量在2008年继续增加并达到历史最高,显示了图像工程在中国继续蓬勃发展的趋势。 相似文献
993.
介绍了20LpVTt法气体流量标准装置的设计原理和方案,并给出了装置中主要参数的测试方法及装置的不确定度评定。 相似文献
994.
995.
A. A. Sirota V. G. Popov V. A. Shulgin D. K. Proskurin 《Optical Memory & Neural Networks》2009,18(2):122-128
A neuronet algorithm of interferometer data processing was developed for detection of microoscillations of the object. The
algorithm parameters analysis has been carried out and sensitivity of the technique has been evaluated using experiment and
simulation data.
The article is published in the original. 相似文献
996.
Hiroki Kikuchi Shigeki Hashimoto Shinichiro Tajiri Tsuneo Hayashi Yutaka Sugawara Michio Oka Yoshiyuki Akiyama Akira Nakamura Naoya Eguchi 《Journal of the Society for Information Display》2009,17(3):263-269
Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed. 相似文献
997.
In this paper, we propose a novel method to achieve both dense 3D reconstruction of the scene and estimation of the camera intrinsic parameters by using coplanarities and other constraints (e.g., orthogonalities or parallelisms) derived from relations between planes in the scene and reflected curves of line lasers captured by a single camera. In our study, we categorize coplanarities in the scene into two types: implicit coplanarities, which can be observed as reflected curves of line lasers, and explicit coplanarities, which are, for example, observed as walls of a building. By using both types of coplanarities, we can construct simultaneous equations and can solve them up to four degrees of freedom. To upgrade the solution to the Euclidean space and estimate the camera intrinsic parameters, we can use metric constraints such as orthogonalities of the planes. Such metric constraints are given by, for example, observing the corners of rectangular boxes in the scene, or using special laser projecting device composed of two line lasers whose laser planes are configured to be perpendicular. 相似文献
998.
Zeyad A. Almutairi Tomasz Glawdel Carolyn L. Ren David A. Johnson 《Microfluidics and nanofluidics》2009,6(2):241-251
This study presents a new Y-channel design for measuring the zeta potential and surface conductance of a solid-liquid pairing
using the current monitoring technique. The new design improves the throughput and reliability of the testing apparatus since
the displacement between two solutions can be repeated many times without interfering with the experiments. It also increases
the accuracy of the measurement by producing sharper start and end transitions for the current–time plot of the solution displacement
process. In this design, efforts have been made to minimize the effects of electrolysis, Joule heating and undesired pressure
driven flow on the measurements. An improvement on the current–time slope analysis is also presented. The Y-channel design
was validated by comparing zeta potential measurements to published results. The zeta potential of several biological buffers
relevant to the microfluidic community in plasma treated PDMS/PDMS and PDMS/Glass microchannels are presented. Preliminary
studies of surface conductivity measurements using the Y-channel design were also conducted and are briefly discussed. 相似文献
999.
Harmony search based algorithm for the optimum design of grillage systems to LRFD-AISC 总被引:1,自引:1,他引:0
Harmony search based optimum design method is presented for the grillage systems. This numerical technique imitates the musical
performance process that takes place when a musician searches for a better state of harmony. Jazz improvisation seeks to find
musically pleasing harmony similar to the optimum design process which seeks to find the optimum solution. The design algorithm
considers the serviceability and ultimate strength constraints which are implemented from Load and Resistance Factor Design—American
Institute of Steel Construction (LRFD-AISC). It selects the appropriate W-sections for the transverse and longitudinal beams
of the grillage system out of 272 discrete W-section designations given in LRFD-AISC. This selection is carried out such that
the design limitations described in LRFD-AISC are satisfied and the weight of the system is the minimum. Many design examples
are considered to demonstrate the efficiency of the algorithm presented. 相似文献
1000.
近十多年教育信息化进程导致社会对教育技术人才专业能力需求的变化,要求教育技术专业能力素质的培养从重教学系统设计转变为重媒体资源开发能力。为应对这种转变,本文从社会需求、专业核心能力、地方本科院校教育技术专业媒体技术类课程设置及综合能力培养方面进行了探讨,并提出了改进的措施与建议。 相似文献