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61.
62.
本文主要讨论了Java的线程及其特点,以及Java中的同步机制。对Java环境下多线程程序的开发做了探讨。 相似文献
63.
随着VLSI技术的发展,工艺映射的目标从面积最小化转向为延时限制下的面积最小化。然而,求延时限制下面积最小化工艺映射技术仅仪在近地阶段。本文给出求解该问题的精确算法以及有关理论结果。 相似文献
64.
S. K. Barton Y. O. Al-Jalili 《International Journal of Satellite Communications and Networking》1993,11(5):287-298
This paper describes a multi-carrier demodulator (MCD) architecture which is capable of demodulating a mixture of signals of different data rates, such as are found in present day transparent transponders. No extra restrictions are placed on the signal transmission rates, bandwidths, channel spacings, frequency stabilities, independent timing, etc. beyond what is already specified by INTELSAT and EUTELSAT. The only exception to this is that no signal should straddle the centre frequency of the existing 72 MHz bandwidth transponders. The system is a refinement of the ‘frequency domain’ filtering approach described in References 7 and 8. The main improvement is in performing the symbol timing recovery in the frquency domain before converting to the time domain. This leads to reductions in computational complexity in both the timing recovery and the frequency to time conversion process. All of these functions can be performed by standard DSP processors. Only the initial time to frequency domain transform requires ASIC technology. 相似文献
65.
Here we present a system of coupled phase oscillators with nearest neighbors coupling, which we study for different boundary
conditions. We concentrate at the transition to the total synchronization. We are able to develop exact solutions for the
value of the coupling parameter when the system becomes completely synchronized, for the case of periodic boundary conditions
as well as for a chain with fixed ends. We compare the results with those calculated numerically.
相似文献
66.
利用声表面波抽头延迟线实现突发通信的快速同步 总被引:12,自引:2,他引:10
在突发通信系统中,同步是系统的关键技术,要求同步快、可靠、易实现、抗干扰能力强。本文介绍用声表面波抽头延迟线完成系统快速同步的方法,可满足系统对同步的要求。 相似文献
67.
首先提出了用GSM900无线基站在做近海海域覆盖时会出现的一些问题,并阐述了其原因:随后给出了处理这些问题的解决方案,最后提供了一个在实际工程中对某海域覆盖型基站的测试实例。 相似文献
68.
本文介绍一个多相同步时序数字电路的时序模型及时序冲突的检验算法。该方法能检查出时序冲突类型,冲突的具体位置及时钟系统设置的合理性。该算法已在Sum-4/SPARC上实现,能快速准确检查出非覆盖多相时钟同时时序电路存在的时序冲突,冲突覆盖率高。 相似文献
69.
We study synchronization transitions and pattern formation on small-world networks consisting of Morris-Lecar excitable neurons in dependence on the information transmission delay and the rewiring probability. In addition, networks formed via gap junctional connections and coupling via chemical synapses are considered separately. For gap-junctionally coupled networks we show that short delays can induce zigzag fronts of excitations, whereas long delays can further detriment synchronization due to a dynamic clustering anti-phase synchronization transition. For the synaptically coupled networks, on the other hand, we find that the clustering anti-phase synchronization can appear as a direct consequence of the prolongation of information transmission delay, without being accompanied by zigzag excitatory fronts. Irrespective of the coupling type, however, we show that an appropriate small-world topology can always restore synchronized activity if only the information transmission delays are short or moderate at most. Long information transmission delays always evoke anti-phase synchronization and clustering, in which case the fine-tuning of the network topology fails to restore the synchronization of neuronal activity. 相似文献
70.
We analyze the critical transitions (a) to endemic states in an SIS epidemiological model, and (b) to full synchronization in an ensemble of coupled chaotic maps, on networks where, at any given time, each node is connected to just one neighbour. In these “monogamous” populations, the lack of connectivity in the instantaneous interaction pattern—that would prevent both the propagation of an infection and the collective entrainment into synchronization—is compensated by occasional random reconnections which recombine interacting couples by exchanging their partners. The transitions to endemic states and to synchronization are recovered if the recombination rate is sufficiently large, thus giving rise to a bifurcation as this rate varies. We study this new critical phenomenon both analytically and numerically. 相似文献