输入向量控制细胞神经网络全局指数稳定

利用输入向量来控制细胞神经网络的稳定性.所得结果表明,当输入向量的绝对值大于某个仅仅只与细胞神经网络的物理参数有关的值时,不附加其它任何条件,细胞神经网络是全局指数稳定的.也讨论了输入向量的部分分量的绝对值大于某个仅仅只与细胞神经网络的物理参数有关的值时,细胞神经网络的全局指数稳定性,所得结论推广和改进了某些已有文献的相应结果.     

具连续分布时滞的抛物型系统的变结构控制

基于比较原理,利用推广的向量Hanalay微分不等式,Dini导数,结合Green公式及不等式分析技术,研究一类具分布时滞的抛物型控制系统的变结构控制问题．首先对所导出的滑动模运动方程,在仅要求系数矩阵是个M-矩阵的条件下,获得了滑动模运动方程全局指数稳定性的充分条件,建立了滑动模运动方程全局指数稳定性定理．其次,设计了仅由状态函数描述的变结构控制器,给出了运动轨线到达滑动模态区的时间的估计．     

Control Charts for Monitoring Linear Profiles with Within‐Profile Correlation Using Gaussian Process Models

Profile monitoring is the utilization of control charts for checking the stability of the quality of a product over time when the product quality is characterized by a function at each time point. Most existing control charts for monitoring profiles are based on the assumption that the observations within each profile are independent of each other, which is often invalid in practice. Successive measurements within profiles often exhibit spatial or serial correlation. This paper focuses on Phase II linear profile monitoring when within‐profile data are correlated. A Gaussian process model is used to describe the within‐profile correlation (WPC). Two Shewhart‐type multivariate control charts are proposed to monitor the linear trend term and the WPC separately in Phase II. Our proposed approaches are compared with alternative methods through numerical simulations in which different in‐control WPCs are considered. Simulation studies show that the proposed control charts are sensitive to changes in the linear trend term when the correlation is strong and effective in detecting large shifts in the WPC. Finally, an example is given to illustrate the implementation of our proposed control charts. Copyright © 2013 John Wiley & Sons, Ltd.     

MML方法在航空航天系统可靠性分析中的应用

修正的极大似然估计法是一种基于经典估计理论系统的可靠性分析方法中较优的算法。主要介绍MML方法及其在航空航天系统可靠性分析中的应用。     

Optimal control of the vibrations of a non-linear string†

A mathematical model for a vibrating non-linear string is constructed. An optimal control problem with a quadratic cost criterion is posed and necessary conditions for optimal controls are derived.     

Optimal schedule and effort considering the penalty cost of schedule delay in software development

This study presents an optimization model that considers the penalty cost due to the contract-schedule delay, when trading off between scheduling and effort in software development project. The optimal combination between the schedule and the effort is shown to depend on the penalty cost. This study also addresses analysis for the effects of software size misestimation and penalty cost change. A simple example is given to illustrate the results of our study.     

Necessary and sufficient conditions for exponential stability of a family of generalized Liénard differential equations

A class of generalized Liénard differential equations determined by prescribed bilateral bounds for the nonlinear terms is considered. Necessary and sufficient conditions for exponential stability of the system expressed in the indicated bounds are found. The results are compared with known sufficient stability conditions obtained via the Lyapunov function method.     

Broadband semi‐parametric estimation of long‐memory time series by fractional exponential models

This article proposes broadband semi‐parametric estimation of a long‐memory parameter by fractional exponential (FEXP) models. We construct the truncated Whittle likelihood based on FEXP models in a semi‐parametric setting to estimate the parameter and show that the proposed estimator is more efficient than the FEXP estimator by Moulines and Soulier (1999) in linear processes. A Monte Carlo simulation suggests that the proposed estimation is more preferable than the existing broadband semi‐parametric estimation.     

低气压对玻璃板表面污闪电压的影响

本提供了玻璃平板染污表面在气压１０１～１０ｋＰａ范围内的交直流放电试验数据，并按此求得正负极性直流伏安特性和交流伏安特性与气压的关系。提出发展中电弧的必要前提是δＰ／δＸ＞０，低气压下弧道因污闪电压随气压的降低而降低。低气压下弧道因冷却减弱而变粗，弧根处因离子的产生和复合减少而使电弧变暗，正离子在电场作用下对污层的撞击减弱，清洁区消失。     

施工企业最佳质量成本函数模型建立及应用

提出利用分部分项工程返修率评价施工企业的质量水平，并利用指数函数模型去模拟、求解最佳质量成本．