共查询到20条相似文献,搜索用时 906 毫秒
1.
Elimination of spiral waves and spatiotemporal chaos by the pulse with a specific spatiotemporal configuration 下载免费PDF全文
Spiral waves and spatiotemporal chaos are sometimes harmful and should be controlled. In this paper spiral waves and spatiotemporal chaos are successfully eliminated by the pulse with a very specific spatiotemporal configuration. The excited position D of spiral waves or spatiotemporal chaos is first recorded at an arbitrary time (to). When the system at the domain D enters a recovering state, the external pulse is injected into the domain. If the intensity and the working time of the pulse are appropriate, spiral waves and spatiotemporal chaos can finally be eliminated because counter-directional waves can be generated by the pulse. There are two advantages in the method. One is that the tip can be quickly eliminated together with the body of spiral wave, and the other is that the injected pulse may be weak and the duration can be very short so that the original system is nearly not affected, which is important for practical applications. 相似文献
2.
3.
本文从数学和物理学的角度分析、讨论了洛伦兹变换的两个重要性质,即“时空对称性”和“时空相对性”。最后又由时空对称平面图推导出了洛伦兹变换。 相似文献
4.
研究了一类噪声诱导的二维复时空系统的同步问题.首先讨论了二维复Ginzburg-Laudau(CGL) 方程随时间和空间变化的时空混沌特性;其次,研究了时空噪声驱动下CGL系统的同步问题.理论上利用线性稳定性分析,得到了常数激励下CGL系统达到稳定态的临界强度;结合噪声的随机性和非零均值特性, 揭示了噪声诱导同步的机理;并从理论上和数值上分别给出了达到同步所需要的控制参数和噪声强度满足的条件,实现了两个非耦合CGL系统的完全同步.结果表明,数值模拟和理论分析有很好的一致性. 相似文献
5.
在狭义相对论的框架下,论述了在时空间隔保持不变的条件下,两个作相对运动的惯性参照系之间的时空变换一定是唯一的,而且这个唯一的变换就是洛伦兹变换。如果不考虑惯性参照系之坐标轴的平移与转动自由度问题,由时空间隔保持不变这一条件就直接得到了通常形式的洛伦兹变换。 相似文献
6.
7.
8.
9.
本文介绍了光纤使用三年来的简单情况;叙述了用氦、氢换气实验的再循环效果;分析了边界层氢和轻、重杂质的时空分布及变化情况;得到了等离子体放电时产生DP和MARFE辐射的时空分布立体图。 相似文献
10.
11.
本文通过实例证明了Schwarzchild解与Booth解是任意空间维Riemann时空中的解的一个亏格 相似文献
12.
13.
定义时空对象代替空间对象作为基本研究单元, 改进传统Moran's I指数为时空Moran's I指数, 以便适于分析道路交通的时空特性; 通过Moran散点图给出时空自相关意义下的交通流时空状态特征分类: 拥堵聚集、畅通聚集、拥堵异质和畅通异质.为说明改进时空Moran's I指数分析法的实际应用价值, 以北京市二环快速路外环方向的车流速度数据为例, 进行时空自相关指标计算, 并从全局与局部自相关两个方面分析时 空自相关指标所反映的交通状态时空分布与演化规律.
关键词:
I指数')" href="#">改进Moran's I指数
交通状态
时空自相关
时空分布 相似文献
14.
15.
A spacetime horizon comprising with a black hole singularity acts like a boundary of a thermal system associated with the notions of temperature and entropy. In the case of static metric of Banados-Teitelboim-Zanelli (BTZ) black hole, the field equations near the horizon boundary can be expressed as a thermal identity dE = TdS+ Pr dA, where E = M is the mass of BTZ black hole, dA is the change in the area of the black hole horizon when the horizon is displaced infinitesimally small, Pr is the radial pressure provided by the source of Einstein equations, S = 41πa is the entropy and T =κ/2π is the Hawking temperature associated with the horizon. This approach is studied further to generalize it for non-static BTZ black hole, showing that it is also possible to interpret the field equation near horizon as a thermodynamic identity dE = TdS + PrdA +Ω+dJ, where Ω+ is the angular velocity and J is the angular momentum of BTZ black hole. These results indicate that the field equations for BTZ black hole possess intrinsic thermodynamic properties near the horizon. 相似文献
16.
本文求出半平面对称非类光电磁场产生的半平面对称静态时空的自旋系数和Weyl张量的复标架分量,结果表明这种时空是Petrov Ⅰ型,即代数一般的。对零矢量和光学标量的性质也作了讨论。
关键词: 相似文献
18.
19.
GAOChang-Jun SHENYou-Gen 《中国物理快报》2003,20(5):618-621
By using the improved brick wall model,we regard the two null horizons in kerr-Newman-de Sitter space-time as two independent thermal equilibrium systems and we calculate the entropies of both horizons due to neutrino field.We propose that the so-called“superradiant”mode cannot be considered because fermion fields does not display supperradiance.In fact,the nonsuperradiant part does exactly show the expected area-law entropy.Moreover,our cut-offε,which does not require an angular cut-off,is independent of angle θ. 相似文献
20.