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We examine how noise interacts with encoding mechanisms of neuronal stimulus in a cold receptor. From ISI series and bifurcation diagrams it is shown that there are considerable differences in interval distributions and impulse patterns caused by purely deterministic simulations and noisy simulations. The ISI-distance can be used as an effective and powerful way to measure the noise effects on spike trains of the cold receptor quantitatively. It is also found that spike trains observed in cold receptors can be more strongly affected by noise for low temperatures than for high temperatures in some aspects; meanwhile, the spike train has greater variability with increasing noise intensity. 相似文献
884.
We consider the problem often encountered in constructing large cluster states, that is, the σx measurements in the depolarizing noise, and present a regulation to calculate the error propagation and the accumulation. Rohde et al. first pointed out the question [Phys. Rev. A 75 (2007) 010302(R)]. A quantitative analysis is given on the disadvantage influence of the probabilistic gate and noisy environment on the construction of two-dimensional (213) scalable cluster states. Positivity of partial transpose criteria is used to predict whether the final state is distillable or not. A critical value on the error tolerance in constructing cluster states is determined, which could be used as a test-bed for successful construction of scalable 2D cluster states. Furthermore, our quantitative analysis would also be helpful to find optimal approach to suppress the noise accumulation. 相似文献
885.
Phase Transition Behavior of LiCr 0.35 Mn0.65O2 under High Pressure by Electrical Conductivity Measurement 下载免费PDF全文
The electrical conductivity of powdered LiCr 0.35 Mn0.65O2 is measured under high pressure up to 26.22 GPa in the temperature range 300-413 K by using a diamond anvil cell. It is found that both conductivity and activation enthalpy change discontinuously at 5.36 GPa and 21.66 GPa. In the pressure range 1.10-5.36 GPa, pressure increases the activation enthalpy and reduces the carrier scattering, which finally leads to the conductivity increase. In the pressure ranges 6.32-21.66 GPa and 22.60-26.22 GPa, the activation enthalpy decreases with pressure increasing, which has a positive contribution to electrical conductivity increase. Two pressure-induced structural phase transitions are found by in-situ x-ray diffraction under high pressure, which results in the discontinuous changes of conductivity and activation enthalpy. 相似文献
886.
2010年是激光发明50周年.文章首先回顾了50年前激光的发明,说明基础科学创新的重大引领作用.接着概述了50年来激光领域的重大进展,包括激光器技术及其应用研究的进展;举例说明了激光应用对基础科学的反馈和推动作用;归纳了高能激光器的几个发展趋势;分析了激光的军事应用及其科学技术支撑.最后给出了激光50年发展史的4点启示和今后的3类发展方向. 相似文献
887.
Dapeng DU 《数学年刊B辑(英文版)》2020,41(6):861-872
The author proposes an alternative way of using fixed point theory to get the existence for semilinear equations. As an example, a nonlocal ordinary differential equation is considered. The idea is to solve homogeneous equations in the linearization. One feature of this method is that it does not need the equation to have special structures, for instance, variational structures, maximum principle, etc. Roughly speaking, the existence comes from good properties of the suitably linearized equation. The idea may have wider application. 相似文献
888.
本文对Lorentz空间型中的正常2-调和超曲面进行了完全分类,它的形状算子的极小多项式的阶数至多是2. 相似文献
889.
In this paper we focus on the sequential k-out-of-n model with covariates. We assume that the lifetime distribution given covariates belongs to the exponential family, and deal with log-linear model of the scale parameter of the exponential distribution. The maximum likelihood estimators (MLEs) of the model parameters with order restrictions are derived and some properties of the MLEs are discussed, and we give the algorithm of MLES and the result of simulation. 相似文献
890.
In this paper,we investigate a discrete semi-ratio dependent predator-prey system with Holling IV type functional response.For general nonautonomous case,sufficient conditions which ensure the permanence and the global stability of the system are obtained.Meanwhile,we discuss the existence of the positive periodic solution and global stability of the system. 相似文献