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191.
1μm宽硅深槽刻蚀技术 总被引:1,自引:1,他引:0
介绍了硅深槽刻蚀的基本原理和影响刻蚀效果的几个主要工艺因素。提出了一种实现1μm宽的硅深槽刻蚀工艺途径;并给出了1μm宽、8μm深、侧壁及底部光洁的硅深槽刻蚀工艺条件。 相似文献
192.
193.
The authors present a method for solving a class of optimization problems with nonsmooth constraints. In particular, they apply the method to the design of narrowband minimum-power antenna array processors which are robust in the presence of errors such as array element placement, look direction misalignment, and frequency offset. They first show that the constrained minimum power problem has a unique global minimum provided that the constraint set is nonempty. Then it is shown how the design problem derived directly from considerations of the sensitivity of the antenna array processor to errors can be transformed into a quadratic programming problem with linear inequality constraints which can be solved efficiently by the standard active set strategy. They also present numerical results for two types of nonsmooth constraints developed to provided robustness. These results confirm the effectiveness of the method 相似文献
194.
Circuit sensitivity to interconnect variation 总被引:1,自引:0,他引:1
Lin Z. Spanos C.J. Milor L.S. Lin Y.T. 《Semiconductor Manufacturing, IEEE Transactions on》1998,11(4):557-568
Deep submicron technology makes interconnect one of the main factors determining the circuit performance. Previous work shows that interconnect parameters exhibit a significant amount of spatial variation. In this work, we develop approaches to study the influence of the interconnect variation on circuit performance and to evaluate the circuit sensitivity to interconnect parameters. First, an accurate interconnect modeling technique is presented, and an interconnect model library is developed. Then, we explore an approach using parameterized interconnect models to study circuit sensitivity via a ring oscillator circuit. Finally, we present an alternative approach using statistical experimental design techniques to study the sensitivity of a large and complicated circuit to interconnect variations 相似文献
195.
用传统的预测效度估计法估计高考预测效度,其估计值往往偏低。为此,本文应用回归分析中混合估计理论提出了高考预测效度的混合估计。这种估计是预测效度的无偏估计,并解决了预测效度估计值偏低的问题。 相似文献
196.
基于邻域统计特性的概率神经网络及其在自动目标识别中的应用 总被引:5,自引:0,他引:5
在概率神经的一种改进模型-FDO网络的基础上,提出在设计网络收敛域时进一步考虑每一像素点周围8邻域的影响,对网络的作用函数加以修,使改进后的网络具有稳定性好且收敛速度快的优点。通过实验对改进前后网络的识别性能加以比较,证明改进后的网络特别适用于噪声图像的识别。 相似文献
197.
198.
Tan Fu Lei Tang Po Chen Horng-Chih Lin Chun-Yen Chang 《Electron Devices, IEEE Transactions on》1995,42(12):2104-2110
A new material, Si-B, is proposed as a solid diffusion source for fabrication of poly-Si contacted p+-n shallow junctions. The junction depth of the Si-B source diode has been measured and compared with that of a BF2+-implanted poly-Si source diode. It was found that the Si-B source diode had a much shallower junction and was less sensitive to thermal budget than the BF2+ source diode. This was attributed to the smaller surface concentration and diffusivity of boron in the silicon in Si-B source diodes. Regarding electrical characteristics of diodes with a junction depth over 500 Å, a forward ideality factor of better than 1.01 over 8 decades and a reverse-current density lower than 0.5 nA/cm2 at -5 V were obtained. As the junction depth shrank to 300 Å, the ideality factor and reverse current density of diodes increased slightly to 1.05 and 1.16 nA/cm2, respectively. These results demonstrated that a uniform ultrashallow p+-n junction can be obtained by using a thin Si-B layer as a diffusion source 相似文献
199.
GaP:(N)的背景光谱和发光尖峰 总被引:1,自引:0,他引:1
获得高分辨GaP(N)光致发光光谱,观察到等电子陷陆束缚激子发光中LO和loc多声子发射,其强度分布答合泊松分布。将声子伴带区分为直接光跃迁和间接光跃迁,并进行了相应讨论,还观察到局域声子效应--光谱相似定律和相当显著的背景光谱。 相似文献
200.
Several distributed power control algorithms that can achieve carrier-to-interference ratio (CIR) balancing with probability one have been proposed previously for cellular mobile systems. In these algorithms, only local information is used to adjust transmitting power. However, a normalization procedure is required in each iteration to determine transmitting power and, thus, these algorithms are not fully distributed. In this paper, we present a distributed power control algorithm which does not need the normalization procedure. We show that the proposed algorithm can achieve CIR balancing with probability one. Moreover, numerical results reveal our proposed scheme performs better than the algorithm presented in Grandhi et al. [1994]. The excellent performance and the fully distributed property make our proposed algorithm a good choice for cellular mobile systems 相似文献