Gauss-Weierstrass算子线性组合的加权Lp-逼近

首先给出了Gauss-Weierstrass算子的一类线性组合在Lp空间加权逼近的正、逆定理和逼近阶的特征刻划的一个一般结果，然后具体给出了一类加Jacobi权逼近的正、逆定理和逼近阶的特征刻划．     

Bayesian analysis of herding behaviour: an application to Spanish equity mutual funds

This paper proposes a dynamic Bayesian rolling window estimation procedure applied to the three‐factor model of Fama and French to analyse herding behaviour in the style exposures of mutual funds. This procedure allows a user to dynamically select the length of the estimation window by means of weighted likelihood functions that discount the loss of information because of time. This method is very flexible and allows us to consider different approaches of detecting herding behaviour by taking into account the uncertainty associated in the estimation of the style coefficients. In particular, the paper first determines the convergence behaviour following the traditional LSV herding measure and then refines this method by removing the influence exerted by market conditions, such as market volatility and returns, on this convergence. This process is empirically illustrated by an application to Spanish equity mutual funds. Copyright © 2014 John Wiley & Sons, Ltd.     

基于灰色关联神经网络的主机热力参数监测研究

为了对船舶主动力系统的热力性能参数进行监测研究,以确保故障预警的可靠性,针对主机热力参数间的非线性关系,建立了基于灰色关联分析的BP神经网络监测模型(GRA-BP),通过灰色关联分析和信息熵加权对网络输入量进行预处理,并利用遗传算法优化网络的初始权值和阈值,提高模型监测精度。最后,以实船主机排气温度为待监测对象,验证了该监测模型的准确性,平均相对误差为0.549℃,优于传统网络的监测结果。     

Random weighted projections,random quadratic forms and random eigenvectors

We present a concentration result concerning random weighted projections in high dimensional spaces. As applications, we prove (1) New concentration inequalities for random quadratic forms. (2) The infinity norm of most unit eigenvectors of a random ±1 matrix is of order . (3) An estimate on the threshold for the local semi‐circle law which is tight up to a factor. © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 47, 792–821, 2015     

高阶多维半离散中心迎风格式及其应用

提出了求解多维对流-扩散方程的四阶半离散中心迎风格式。该格式以中心加权基本无振荡(CWENO)重构为基础,同时考虑到在Riemann扇内波传播的局部速度,从而更加准确地估计出了局部Riemann扇的宽度,最终既回避了网格的交错,又降低了格式的数值粘性,建立了介于迎风格式和中心格式之间的半离散中心迎风格式。本文还将该四阶半离散中心迎风格式与涡度-流函数方法相结合,有效地求解了二维不可压Euler方程组和Navier-Stokes方程组。     

Detecting and describing the modular structures of weighted networks

In the functional properties of complex networks, modules play a central role. In this paper, we propose a new method to detect and describe the modular structures of weighted networks. In order to test the proposed method, as an example, we use our method to analyse the structural properties of the Chinese railway network. Here, the stations are regarded as the nodes and the track sections are regarded as the links. Rigorous analysis of the existing data shows that using the proposed algorithm, the nodes of network can be classified naturally. Moreover, there are several core nodes in each module. Remarkably, we introduce the correlation function $G_{rs}$, and use it to distinguish the different modules in weighted networks.     

石油企业生产经营系统监测预警指标体系和预警方法研究

为保证石油企业的持续稳定发展，本文根据石油企业的生产经营特点，建立了石油企业生产经营系统监测预警指标体系，在此基础上应用加权平均法构建了石油企业生产经营综合评价预警模型，并以胜利油田为例加以应用分析。     

Difference of generalized integration operators on the space of Cauchy transforms

In this paper, the boundedness and compactness of the differences of generalized integration operators from the space of Cauchy integral transforms to the Bloch-type spaces and the weighted Dirichlet spaces are investigated.     

Reduced‐cost sparsity‐exploiting algorithm for solving coupled‐cluster equations

We present an algorithm for reducing the computational work involved in coupled‐cluster (CC) calculations by sparsifying the amplitude correction within a CC amplitude update procedure. We provide a theoretical justification for this approach, which is based on the convergence theory of inexact Newton iterations. We demonstrate by numerical examples that, in the simplest case of the CCD equations, we can sparsify the amplitude correction by setting, on average, roughly 90% nonzero elements to zeros without a major effect on the convergence of the inexact Newton iterations.     

无线传感器网络的自身定位算法研究

自身定位算法在无线传感器网络技术的目标定位和跟踪等方面起着举足轻重的作用,而算法的优劣直接影响着自身定位和目标定位的精度．以传统的DV-hop算法为依据,提出了一种WDH（Weighted-DV-hop）定位算法,在获得跳数的步骤中,根据接收到的传播信号区分强弱程度,并取0．d．5或1作为跳数递增量的加权修正值,来得到新的跳数．最后通过Matlab平台实现算法的验证,表明其可以明显地提高定位的精度．