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751.
后摩尔时代的封装技术 总被引:2,自引:1,他引:1
童志义 《电子工业专用设备》2008,37(9)
综述了进入后摩尔时代半导体业界面临制造技术极限的挑战所进行的各种应对措施的现状,着重介绍了叠层封装、系统级封装、晶圆级封装、硅通孔技术等一些新型的三维垂直封装技术在电子电路集成方面的进展及高密度3D芯片封装的前景。 相似文献
752.
《Discrete Mathematics》2022,345(6):112835
In this work we describe the spectra of all rational numbers that could be a density of a strictly balanced uniform hypergraph. We also introduce some specific constructions of strictly balanced uniform hypergraphs, and exploit them to generalize some results about Zero-One Law and Zero-One k-Law to the case of random uniform hypergraphs. 相似文献
753.
通过预实验确定智能手机磁传感器的位置后,用其测量亥姆霍兹线圈轴线的磁场分布,验证毕奥-萨伐尔定律及磁场的叠加原理,提供一种较为精确而简便的测量磁场的新方法. 相似文献
754.
755.
Jun Xu Yong‐Bing Tang Xue Chen Chun‐Yan Luan Wen‐Feng Zhang Juan Antonio Zapien Wen‐Jun Zhang Hoi‐Lun Kwong Xiang‐Min Meng Shuit‐Tong Lee Chun‐Sing Lee 《Advanced functional materials》2010,20(23):4190-4195
Bundles of homogeneously alloyed Cu2?x(SySe1?y) nanowires with various compositions (0 ≤ y ≤ 1) are controllably prepared via a simple water‐evaporation method under mild conditions. It is found that the nanowire bundles have similar copper contents (0.37 ≤ x ≤ 0.44) and morphologies, and the same face centered cubic (fcc) crystal structure and growth orientation of [110] over the entire composition range of y. To the best of the authors' knowledge, this is the first report on cubic phased ternary Cu2?x(SySe1?y) compounds. It is found that lattice parameter of the Cu2?x(SySe1?y) compound changes linearly with the S content. It is also shown that the direct and the indirect bandgaps of the nanowires vary quadratically with the S content and have bowing parameters of 0.20 and 0.21 eV respectively. Energy‐gap‐tuning via compositional change is achieved for both the direct (1.48?1.87 eV) and the indirect (0.50?0.90 eV) bandgaps. The trends of lattice parameter and bandgap variations are consistent with those described by Végard's Law. 相似文献
756.
757.
菲涅耳数字全息在图像加密中的应用 总被引:2,自引:1,他引:1
基于小波变换和光学菲涅尔变换原理,提出一种新的数字水印算法。首先,原始的水印图像经过离散菲涅尔变换转化成数字全息图,并对数字全息图进行灰度变换;再对宿主图像进行一层小波分解;最后将变换后的数字全息图嵌入到宿主图像较大的小波系数中。实验结果表明,该水印算法具有较强的鲁棒性,能抵抗较大的剪切、有损压缩和滤波等攻击。 相似文献
758.
In this letter, a parametric analysis of the Fresnel‐field antenna measurement method is performed for a square aperture. As a result, the optimum number of Fresnel fields for one far‐field point is guided as Mopt=Nopt=D2/λR+5, where D is the antenna diameter, λ is the wavelength, and R is the distance between the source antenna and the antenna under test. For the aperture size 5 ≤ Lx/λ ≤ 20, the tolerable distances for gain errors of 0.5 dB and 0.2 dB can be guided as R0.5 dB ≈ 1.2Lx/λ and R0.2 dB ≈ 2.0Lx/λ, where Lx is the lateral length of the square aperture. The tolerable distances for 20 ≤ Lx/λ ≤ 200 are also proposed. This measurement guideline can be fully utilized when performing the Fresnel‐field antenna measurement method. 相似文献
759.
《Stochastic Processes and their Applications》2020,130(1):262-296
Focusing on stochastic systems arising in mean-field models, the systems under consideration belong to the class of switching diffusions, in which continuous dynamics and discrete events coexist and interact. The discrete events are modeled by a continuous-time Markov chain. Different from the usual switching diffusions, the systems include mean-field interactions. Our effort is devoted to obtaining laws of large numbers for the underlying systems. One of the distinct features of the paper is the limit of the empirical measures is not deterministic but a random measure depending on the history of the Markovian switching process. A main difficulty is that the standard martingale approach cannot be used to characterize the limit because of the coupling due to the random switching process. In this paper, in contrast to the classical approach, the limit is characterized as the conditional distribution (given the history of the switching process) of the solution to a stochastic McKean–Vlasov differential equation with Markovian switching. 相似文献
760.
Moshe Kress Jonathan P. Caulkins Gustav Feichtinger Dieter Grass Andrea Seidl 《European Journal of Operational Research》2018,264(1):46-54
Lanchester (1960) modeled combat situations between two opponents, where mutual attrition occurs continuously in time, by a pair of simple ordinary (linear) differential equations. The aim of the present paper is to extend the model to a conflict consisting of three parties. In particular, Lanchester’s main result, i.e. his Square Law, is adapted to a triple fight. However, here a central factor – besides the initial strengths of the forces – determining the long run outcome is the allocation of each opponent’s efforts between the other two parties. Depending on initial strengths, (the) solution paths are calculated and visualized in appropriate phase portraits. We are able identify regions in the state space where, independent of the force allocation of the opponents, always the same combatant wins, regions, where a combatant can win if its force allocation is wisely chosen, and regions where a combatant cannot win itself but determine the winner by its forces allocation. As such, the present model can be seen as a forerunner of a dynamic game between three opponents. 相似文献