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991.
The main result of this paper is a nonlocal version of Harnack's inequality for a class of parabolic nonlocal equations. We additionally establish a weak Harnack inequality as well as local boundedness of solutions. None of the results require the solution to be globally positive.  相似文献   
992.
As is known, if B=(Bt)t[0,T] is a G-Brownian motion, a process of form 0tηsdBs?0t2G(ηs)ds, ηMG1(0,T), is a non-increasing G-martingale. In this paper, we shall show that a non-increasing G-martingale cannot be form of 0tηsds or 0tγsdBs, η,γMG1(0,T), which implies that the decomposition for generalized G-Itô processes is unique: For arbitrary ζHG1(0,T), ηMG1(0,T) and non-increasing G-martingales K,L, if 0tζsdBs+0tηsds+Kt=Lt,t[0,T],then we have η0, ζ0 andKt=Lt. As an application, we give a characterization to the G-Sobolev spaces introduced in Peng and Song (2015).  相似文献   
993.
We design a quantized sampled-data controller for synchronization of delayed chaotic Lur’e systems. A new approach, extended Wirtinger-inequality-based Lyapunov–Krasovskii functional, is firstly proposed. This approach grasps more sampling information by introducing more free matrices in comparison with some existing methods. Using the system information at the dynamic partitioning point, a zero equality is formulated to fully utilize the inner sampling information. Based on the new approach and zero equality, some novel synchronization criteria are established. In the meantime, the desired quantized sampled-data control gain is obtained with larger sampling period than those in the existing works. Finally, two numerical examples illustrate the merits of the method.  相似文献   
994.
In this paper, we classify all capable nilpotent Lie algebras with the derived subalgebra of dimension 2 over an arbitrary field. Moreover, the explicit structure of such Lie algebras of class 3 is given.  相似文献   
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998.
Yang  Jin Hua  Yang  Qi  Pang  Xue Cheng 《数学学报(英文版)》2019,35(12):1972-1978
In this paper, we continue to discuss the normality concerning omitted holomorphic function and get the following result. Let F be a family of meromorphic functions on a domain D, k ≥ 4 be a positive integer, and let a(z) and b(z) be two holomorphic functions on D, where a(z) 0 and f(z) ≠ ∞ whenever a(z)=0. If for any f ∈ F, f'(z) -a(z)fk(z) ≠ b(z), then F is normal on D.  相似文献   
999.
Auxiliary population information is often available in finite population inference problems, and the empirical likelihood (EL) approach has been demonstrated to be flexible and useful for such problems. The present paper concerns EL when interest centers on inference for the mean of the baseline distribution under two-sample density ratio models. Although dual EL is a convenient technical tool since it has the same maximum point and maximum likelihood as DRM-based EL, it can not combine such auxiliary information into the likelihood conveniently and may have loss of efficiency. By contrast, the classical EL approach of Qin and Lawless\ucite{21} does not have this problem and incorporate seamlessly auxiliary information. Based on the EL using auxiliary information and the dual EL methods, we construct both point and interval estimations and make a careful comparison. Though the point estimation efficiency gain obtained by the former is not noticeable, we find that they may have different performances in interval estimation. In terms of coverage accuracy, the two intervals are comparable for not or moderate skewed populations, and the EL interval using auxiliary information can be much superior for severely skewed populations.  相似文献   
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