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991.
针对随机共振方法以系统的参数和噪声强度的匹配为研究背景的局限性,为解决级联双稳系统参数的合理选取的问题及克服自适应随机共振单参数优化的不足之处,提出了一种基于级联随机共振与自适应粒子群(APSO)算法相结合的方法。该方法以系统的输出信噪比为优化目标函数,采用自适应粒子群算法较强的全局搜索能力和粒子(待优化参数)的多样性,对级联双稳态随机共振的级联系统参数进行同步优化,使系统处于最佳随机共振工作状态。仿真结果表明,该方法可以提高输出信噪比及算法的收敛速度,实现良好的检测效果。 相似文献
992.
刘长远 《太赫兹科学与电子信息学报》2023,21(1):44-49
短波环境中存在着大量令人感兴趣的莫尔斯信号,为了降低人工侦收成本,研究了莫尔斯信号在短波环境下的窄带信号自动识别技术。针对短波信道环境,提出一种联合时频域特征的快速识别算法,并给出短波环境下莫尔斯窄带识别算法的流程设计,最后获得算法的实测结果。实验结果表明,该算法下的莫尔斯识别具有较快的速度和较好的识别率,以及较低的虚警率和漏警率。 相似文献
993.
Analysis of Physiological Responses and Use of Fuzzy Information Granulation–Based Neural Network for Recognition of Three Emotions 下载免费PDF全文
In this study, we investigate the relationship between emotions and the physiological responses, with emotion recognition, using the proposed fuzzy information granulation–based neural network (FIGNN) for boredom, pain, and surprise emotions. For an analysis of the physiological responses, three emotions are induced through emotional stimuli, and the physiological signals are obtained from the evoked emotions. To recognize the emotions, we design an FIGNN recognizer and deal with the feature selection through an analysis of the physiological signals. The proposed method is accomplished in premise, consequence, and aggregation design phases. The premise phase takes information granulation using fuzzy c‐means clustering, the consequence phase adopts a polynomial function, and the aggregation phase resorts to a general fuzzy inference. Experiments show that a suitable methodology and a substantial reduction of the feature space can be accomplished, and that the proposed FIGNN has a high recognition accuracy for the three emotions using physiological signals. 相似文献
994.
Ahmad M. Rateb Sharifah K. S. Yusof 《International Journal of Communication Systems》2015,28(3):546-559
Compressed sensing is an emerging technique in the field of digital signal acquisition. It promises almost exact recovery of high‐dimensional signals from a very small set of measurements. However, this technique is challenged by the task of recovering signals immersed in noise. In this paper, we derive upper and lower bounds on mean squared recovery error of noisy signals. These bounds are valid for any number of acquired measurements and at any signal‐to‐noise ratio. This work is highly useful for the design of any compressed sensing‐based real world application by quantifying recovery error entailed with realistic digital signal acquisition scenarios. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
995.
996.
Blind Source Separation of Instantaneous Mixture of Delayed Sources Using High‐Order Taylor Approximation 下载免费PDF全文
Wei Zhao Zhigang Yuan Yuehong Shen Yufan Cao Yimin Wei Pengcheng Xu Wei Jian 《ETRI Journal》2015,37(4):727-735
This paper deals with the problem of blind source separation (BSS), where observed signals are a mixture of delayed sources. In reference to a previous work, when the delay time is small such that the first‐order Taylor approximation holds, delayed observations are transformed into an instantaneous mixture of original sources and their derivatives, for which an extended second‐order blind identification (SOBI) approach is used to recover sources. Inspired by the results of this previous work, we propose to generalize its first‐order Taylor approximation to suit higher‐order approximations in the case of a large delay time based on a similar version of its extended SOBI. Compared to SOBI and its extended version for a first‐order Taylor approximation, our method is more efficient in terms of separation quality when the delay time is large. Simulation results verify the performance of our approach under different time delays and signal‐to‐noise ratio conditions, respectively. 相似文献
997.
998.
Consider the lattice of bounded linear operators on the space of Borel measures on a Polish space. We prove that the operators which are continuous with respect to the weak topology induced by the bounded measurable functions form a sublattice that is lattice isomorphic to the space of transition kernels. As an application we present a purely analytic proof of Doob's theorem concerning stability of transition semigroups. 相似文献
999.
1000.
一种数字信号调制方式识别方法 总被引:2,自引:2,他引:0
数字信号调制方式的识别是近年来迅速发展起来的一门新技术,它是信号分析领域的重要组成部分。调制识别技术具有很高的实用价值。在军用和民用方面都有重要应用,如通过调制识别技术查清相关信号的参数和性质。这里针对短波信道条件下的MPSK信号调制识别问题,研究了一种基于功率谱和谱相关为特征的调制方式的分类与识别方案。该方案中提取了以信号功率谱的各种特征为主要的特征参数,通过对BPSK、QPSK、8PSK几种常用的数字信号进行仿真识别表明,该方法简单便于工程实现,具有很好的实用性。 相似文献