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951.
952.
参考目标模型中混入的背景噪声会弱化目标特征的描述,导致目标跟踪定位误差。为减少误差,依据目标与背景处于不同深度平面的特点,提出了基于深度信息辅助的和改进的背景加权直方图的MeanShift跟踪算法,能够有效削弱核窗口中的背景干扰信息,突出目标的颜色特征信息,并适时自适应更新核带宽,减少因目标尺寸变小时引入较多的背景干扰信息。实验结果表明该算法迭代次数更少,具有良好的跟踪定精度。 相似文献
953.
We propose a proof system for reasoning on certain specifications of secure authentication systems. For this purpose, a new logic, sequence-indexed linear-time temporal logic (SLTL), is obtained semantically from standard linear-time temporal logic (LTL) by adding a sequence modal operator that represents a sequence of symbols. By this sequence modal operator, we can appropriately express message flows between clients and servers and states of servers in temporal reasoning. A Gentzen-type sequent calculus for SLTL is introduced, and the completeness and cut-elimination theorems for it are proved. SLTL is also shown to be PSPACE-complete and embeddable into LTL. 相似文献
954.
Rui‐Qing Ma Richard Hewitt Kamala Rajan Jeff Silvernail Ken Urbanik Michael Hack Julie J. Brown 《Journal of the Society for Information Display》2008,16(1):169-175
Abstract— Organic light‐emitting‐device (OLED) devices are very promising candidates for flexible‐display applications because of their organic thin‐film configuration and excellent optical and video performance. Recent progress of flexible‐OLED technologies for high‐performance full‐color active‐matrix OLED (AMOLED) displays will be presented and future challenges will be discussed. Specific focus is placed on technology components, including high‐efficiency phosphorescent OLED technology, substrates and backplanes for flexible displays, transparent compound cathode technology, conformal packaging, and the flexibility testing of these devices. Finally, the latest prototype in collaboration with LG. Phillips LCD, a flexible 4‐in. QVGA full‐color AMOLED built on amorphous‐silicon backplane, will be described. 相似文献
955.
Ken Naitoh 《Artificial Life and Robotics》2008,13(1):10-17
The frequencies of purines and pyrimidines in double-strand DNA are in a symmetric ratio of 1: 1, while the asymmetric density
ratios of purines and pyrimidines in RNA and artificial ribozymes are between 1: 1 and approximately 1: 1.5. The frequency
ratio in DNA is deterministic, while that in RNA is fairly stochastic. Symbiotic fusion of deterministic symmetry and stochastic
asymmetry, which can be seen at the molecular, cell and whole-body levels, is a key concept for understanding the self-organizing
processes in living organisms. The left-right symmetric distribution of arms and legs is observed in outward appearance, although
the inner body, including the heart and the liver, is asymmetric. A minimum hypercycle of four cycles at the origin of life
is also in the symbiotic fusion of symmetry and asymmetry. The inevitability of deterministic symmetry and stochastic asymmetry
underlying life is systematically revealed on the basis of physics as the weft and molecular biology as the warp.
This work was presented in part at the First European Workshop on Artificial Life and Robotics, Vienna, Austria, July 12–13,
2007 相似文献
956.
Ogura S Kaneko K Miyajima S Ohshima K Yamaguchi K Mochizuki T 《Proteomics. Clinical applications》2008,2(12):1620-1627
Proteins secreted from specific cancer cells have a high potential for use as tumor markers. We identified secreted proteins produced by 15 different carcinoma cell lines grown in serum-free medium using MS/MS. Proneurotensin/neuromedin N (proNT/NMN) was found in conditioned medium from four of seven small cell lung carcinoma cell lines but not from eight nonsmall cell lung carcinoma cell lines. These results indicate proNT/NMN has potential as a specific tumor marker of small cell lung carcinoma. 相似文献
957.
958.
PC energy use is a growing cost to enterprises, with most machines remaining fully powered on, even while idle, for most of the time. The Network Connectivity Proxy maintains network presence for PCs but lets them sleep while idle, thus saving energy and reducing total cost of ownership. 相似文献
959.
A decomposition of fuzzy relations 总被引:1,自引:0,他引:1
Pedrycz W. Hirota K. Sessa S. 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2001,31(4):657-663
This study is concerned with a decomposition of fuzzy relations, that is their representation with the aid of a certain number of fuzzy sets. We say that some fuzzy sets decompose an original fuzzy refraction if the sum of their Cartesian products approximate the given fuzzy relation. The theoretical underpinnings of the problem are presented along with some linkages with Boolean matrices (such as a Schein rank). Subsequently, we reformulate the decomposition of fuzzy relations as a problem of numeric optimizing and propose a detailed learning scheme leading to a collection of decomposing fuzzy sets. The role of the decomposition in a general class of data compression problems (including those of image compression and rule-based system condensation) is formulated and discussed in detail. 相似文献
960.
We address the problem of filtering, selecting and placing labels on a dynamic map, which is characterized by continuous zooming and panning capabilities. This consists of two interrelated issues. The first is to avoid label popping and other artifacts that cause confusion and interrupt navigation, and the second is to label at interactive speed. In most formulations the static map labeling problem is NP-hard, and a fast approximation might have O(n log n) complexity. Even this is too slow during interaction, when the number of labels shown can be several orders of magnitude less than the number in the map. In this paper we introduce a set of desiderata for "consistent" dynamic map labeling, which has qualities desirable for navigation. We develop a new framework for dynamic labeling that achieves the desiderata and allows for fast interactive display by moving all of the selection and placement decisions into the preprocessing phase. This framework is general enough to accommodate a variety of selection and placement algorithms. It does not appear possible to achieve our desiderata using previous frameworks. Prior to this paper, there were no formal models of dynamic maps or of dynamic labels; our paper introduces both. We formulate a general optimization problem for dynamic map labeling and give a solution to a simple version of the problem. The simple version is based on label priorities and a versatile and intuitive class of dynamic label placements we call "invariant point placements". Despite these restrictions, our approach gives a useful and practical solution. Our implementation is incorporated into the G-Vis system which is a full-detail dynamic map of the continental USA. This demo is available through any browser 相似文献