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991.
992.
针对视频图像中单个运动目标的分割问题,提出了一种基于Kirsch边缘算子的视频运动目标分割算法,该算法将Kirsch算子检测到的边缘作为主分割信息,运动矢量场作为次要分割信息。首先利用双重尺度的运动矢量场进行累加和滤波处理来获得辅助分割信息;然后将Kirsch算子的模板分解为差值模板和公共模板以提高边缘的抗噪性;最后用自适应状态标记的方法将边缘信息和运动矢量信息相融合来准确地分割运动目标。实验结果表明该方法分割比较精确。 相似文献
993.
Chen Su Xinxing Xia Haifeng Li Xu Liu Cuifang Kuang Jun Xia Baoping Wang 《中国光学快报(英文版)》2014,12(6):60007-29
Based on light field reconstruction and motion recognition technique,a penetrable interactive floating 3D display system is proposed.The system consists of a high-frame-rate projector,a flat directional diffusing screen,a high-speed data transmission module,and a Kinect somatosensory device.The floating occlusioncorrect 3D image could rotate around some axis at different speeds according to user’s hand motion.Eight motion directions and speed are detected accurately,and the prototype system operates efficiently with a recognition accuracy of 90%on average. 相似文献
994.
The resolution of the parallax image is inversely proportional to the view number in the horizontal direction for the traditional autostereoscopic display based on a parallax barrier. To balance the resolution in the vertical and horizontal directions, two parallax interleaved barriers are designed. The liquid crystal display panel provides the synthetic image with square pixel units, and the pixels in a unit are distributed to different horizontal views. Two parallax interleaved barriers work together to modulate pixels in vertical and horizontal directions. 3D display with uniform resolution and low crosstalk is demonstrated. 相似文献
995.
In this paper, a recently introduced cellular automata (CA) model is used for a statistical analysis of the inner micro-scopic structure of synchronized traffic flow. The analysis focuses on the formation and dissolution of clusters or platoons of vehicles, as the mechanism that causes the presence of this synchronized traffic state with a high flow. This platoon formation is one of the most interesting phenomena observed in traffic flows and plays an important role both in manual and automated highway systems (AHS). Simulation results, obtained from a single-lane system under periodic boundary conditions indicate that in the density region where the synchronized state is observed, most vehicles travel together in pla- toons with approximately the same speed and small spatial distances. The examination of velocity variations and individual vehicle gaps shows that the flow corresponding to the synchronized state is stable, safe and highly correlated. Moreover, results indicate that the observed platoon formation in real traffic is reproduced in simulations by the relation between vehicle headway and velocity that is embedded in the dynamics definition of the CA model. 相似文献
996.
Consequent entanglement concentration of a less-entangled electronic cluster state with controlled-not gates 下载免费PDF全文
We present a highly efficient entanglement concentration protocol (ECP) for a four-electron system in a less-entangled cluster state. In this ECP, we only require one pair of less-entangled electron cluster states and one ancillary electron to complete the task. With the help of the controlled-not (CNOT) gate, the concentrated maximally entangled state can be retained for further application with some success probability. On the other hand, the discarded items can be reused to obtain a high success probability. All the features make this ECP useful in the current quantum information field. 相似文献
997.
Copper phthalocyanine junctions, fabricated by magnetron sputtering and evaporating methods, show multi-polar (unipolar and bipolar) resistance switching and the memory effect. The multi-polar resistance switching has not been observed simultaneously in one organic material before. With both electrodes being cobalt, the unipolar resistance switching is universal. The high resistance state is switched to the low resistance state when the bias reaches the set voltage. Generally, the set voltage increases with the thickness of copper phthalocyanine and decreases with increasing dwell time of bias. Moreover, the low resistance state could be switched to the high resistance state by absorbing the phonon energy. The stability of the low resistance state could be tuned by different electrodes. In Au/copper phthalocyanine/Co system, the low resistance state is far more stable, and the bipolar resistance switching is found. Temperature dependence of electrical transport measurements demonstrates that there are no obvious differences in the electrical transport mechanism before and after the resistance switching. They fit quite well with Mott variable range hopping theory. The effect of A1203 on the resistance switching is excluded by control experiments. The holes trapping and detrapping in copper phthalocyanine layer are responsible for the resistance switching, and the interfacial effect between electrodes and copper phthalocyanine layer affects the memory effect. 相似文献
998.
针对现有爬壁机器人规划算法难以实现在线自适应高效规划的问题,设计了一种基于模糊K-Means算法和经典Sarsa(λ)算法自适应爬壁机器人规划算法;首先,对爬壁机器人的动力学模型进行了建模和分析,然后,对爬壁机器人规划中的状态进行自适应聚集从而实现值函数的近似,设计了K值可变的改进模糊K均值聚类算法对状态进行自适应地在线聚类,将聚类中心对应的值函数作为整个聚类所有数据对象的值函数的近似值,最后,对基于模糊K均值聚类算法和Sarsa(λ)算法的爬壁机器人在线规划算法进行了定义和描述,在MATLAB环境下对简单障碍物场景和复杂障碍物场景分别仿真实验,实验结果表明文中方法能有效地进行路径规划,随着情节数的增加,规划结果逐渐收敛到最优值,同时在环境变化时,收敛效果不受影响,具有较好的稳定性,是一种高效地实现爬壁机器人在线规划的方法。 相似文献
999.
轮轨作用力对车辆的运行品质及安全有重要影响;现有轮轨力测量方法采用了特制的测力轮对测量和轨道静态测量,其成本高、周期长、稳定性差;对现有轮轨力测量方法进行了研究,提出了降维状态观测器的方法观测轮轨力;建立单轮对车辆轨道垂向耦合模型,以车辆状态响应值与轨道激励作为降维状态观测器的输入;通过Matlab仿真计算,得出轮对振动位移的观测值快速收敛于仿真值,轮轨力有很好的吻合性;随着车辆速度增加振动位移收敛时间变长,轮轨力误差增大;结果表明,在一定条件下,此方法能够很好的地观测轮轨力的大小,为轮轨力的实时估计提供一种的新方法。 相似文献
1000.
现有的ARINC429总线通信检测设备无法满足对综合显示控制系统中多通道信号同时检测的需求,为了解决这一问题,重点研究了PCI接口的总线通信板卡设计,给出了利用C#语言设计综合显示控制系统测试软件的方法;设计时,运用结构化、模块化、标准化的思想确立了总体方案;利用板卡提供的接口函数实现了用户应用层程序、PCI驱动程序、接口底层控制程序的衔接;采用Form窗体实现了可视化操作界面;试验时通过对比测试软件和综合显示控制系统上的收发数据,可以快速确定存在问题的总线通道,实现对系统的故障分析和诊断。 相似文献