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991.
Wang JX Liao SH Zhu XH Wang Y Ling CX Ding X Fang YM Zhang XH 《Computer methods and programs in biomedicine》2011,104(3):472-479
This paper presents an intuitive nose surgery planning and simulation system, using 3D laser scan image and lateral X-ray image, to provide high quality prediction of the postoperative appearance, and design the patient specific prosthesis model automatically. After initial registration, the internal surface of soft tissue at the nose region was generated by the statistical data for soft tissue thickness adapted by the individual thickness information from the X-ray image. Then, the sketch contour of the 3D scan data on the lateral X-ray image was modified manually or adjusted automatically according to some aesthetic statistical data, to drive the simulation in real time by the state-of-the-art Laplacian surface deformation method. When satisfied with the 3D postoperative appearance, the deformation was mapped to the internal surface of soft tissue, and the change before and after simulation was utilized to generate the patient specific prosthesis model automatically. The surgeons who used the system confirmed that this planning system is attractive and has potential for daily clinical practice. 相似文献
992.
Ilias Diakonikolas Homin K. Lee Kevin Matulef Rocco A. Servedio Andrew Wan 《Algorithmica》2011,61(3):580-605
We give the first algorithm that is both query-efficient and time-efficient for testing whether an unknown function f:{0,1}
n
→{−1,1} is an s-sparse GF(2) polynomial versus ε-far from every such polynomial. Our algorithm makes poly(s,1/ε) black-box queries to f and runs in time n⋅poly(s,1/ε). The only previous algorithm for this testing problem (Diakonikolas et al. in Proceedings of the 48th Annual Symposium on
Foundations of Computer Science, FOCS, pp. 549–558, 2007) used poly(s,1/ε) queries, but had running time exponential in s and super-polynomial in 1/ε. 相似文献
993.
Maxim A. Babenko 《Algorithmica》2011,61(4):898-922
Let G=(VG,AG) be a digraph and let S
⊔
T be a bipartition of VG. A bibranching is a subset B⊆AG such that for each node s∈S there exists a directed s–T path in B and, vice versa, for each node t∈T there exists a directed S–t path in B. 相似文献
994.
Given a set of points in the plane, and a sweep-line as a tool, what is best way to move the points to a target point using a sequence of sweeps? In a sweep, the sweep-line is placed at a start position somewhere in the plane, then moved orthogonally and continuously to another parallel end position, and then lifted from the plane. The cost of a sequence of sweeps is the total length of the sweeps. Another parameter of interest is the number of sweeps. Four variants are discussed, depending on whether the target is a hole or a pile, and whether the target is specified or freely selected by the algorithm. Here we present a ratio 4/π≈1.27 approximation algorithm in the length measure, which performs at most four sweeps. We also prove that, for the two constrained variants, there are sets of n points for which any sequence of minimum cost requires 3n/2?O(1) sweeps. 相似文献
995.
<正>目前,嵌入式技术日益成熟并越来越广泛地应用于工业自动化、医疗监测、通信、汽车电子、生活娱乐等各个领域。迄今为止,只要我们目之能及,嵌入式系统已经"无处不在"、"无所不能"。嵌入式技术在中国有着巨大的发展潜力和市场需求,中国嵌入式市场朝气蓬勃,发展 相似文献
996.
<正>一直以来,基于传感器的系统电路的设计不仅极为耗时、复杂,而且需要针对每个系统开发专用的设计方案。从伊始的挑选传感器、搜索并分析元器件、评估系统性能,到线路布局及电路板装配、核实设计,直至最终的系统建模,很多工程师都要花费几周甚至几个月的时间才能成功开发出一款定制的模拟传感器解决方案,这无疑成为困扰众多工程师的一大难题。 相似文献
997.
998.
Tich Phuoc Tran Thi Thanh Sang Nguyen Poshiang Tsai Xiaoying Kong 《Artificial Intelligence Review》2011,35(4):369-382
In the modern age of Internet connectivity, advanced information systems have accumulated huge volumes of data. Such fast
growing, tremendous amount of data, collected and stored in large databases has far exceeded our human ability to comprehend
without proper tools. There has been a great deal of research conducted to explore the potential applications of Machine Learning
technologies in Security Informatics. This article studies the Network Security Detection problems in which predictive models
are constructed to detect network security breaches such as spamming. Due to overwhelming volume of data, complexity and dynamics
of computer networks and evolving cyber threats, current security systems suffer limited performance with low detection accuracy
and high number of false alarms. To address such performance issues, a novel Machine Learning algorithm, namely Boosted Subspace
Probabilistic Neural Network (BSPNN), has been proposed which combines a Radial Basis Function Neural Network with an innovative
diversity-based ensemble learning framework. Extensive empirical analyses suggested that BSPNN achieved high detection accuracy
with relatively small computational complexity compared with other conventional detection methods. 相似文献
999.
搜索引擎是目前人们寻找网络资源最常用的方式,本系统依照搜索引擎的设计原理,采用多Agent方式,通过对索引模块参数设置实现对校内网不同的资源进行统一整合,建立校内网资源的搜索引擎。该搜索引擎为学校内网提供资源共享的新方式,提高校内资源的利用率,减轻校内网带宽的压力。Abstract: Search engine is the most common way to seek network resources, this system was designed in accordance with the principles of search engine with multi-Agent approach, established search engine of school network resources by setting the index module parame 相似文献
1000.
鼻炎滴剂是中西复方制剂,主要成分有黄芩苷、盐酸麻黄碱、金银花、辛夷油、冰片等.本文研究建立了数学分离-多波长直线回归法,用于测定鼻炎滴剂中黄芩苷和盐酸麻黄碱的含量.黄芩苷和盐酸麻黄碱的最大吸收波长分别为278.0 nm和257.0 nm,将2组分吸收强度较大的242.0 nm~283.0 nm选为测定范围.在测定范围内选择42个点进行测定,使用数学分离-多波长直线回归方法计算分析,直接测定了鼻炎滴剂中的黄芩苷和盐酸麻黄碱含量.本文研究使用的市售鼻炎滴剂中2种药效成分的平均回收率和相对标准偏差分别为102.0%,0.86%和98.2%,0.87%.数学分离-多波长直线回归法简单、快速、准确、适用于鼻炎滴剂的质量控制过程. 相似文献