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191.
This paper is devoted to the investigation of stability for a class of coupled impulsive Markovian jump reaction-diffusion systems on networks (CIMJRDSNs). By using graph theory, a systematic method is provided to construct global Lyapunov functions for the CIMJRDSNs. Based on Lyapunov functions and stochastic analysis method, some novel stability principles associated with the topology property of the networks are established.  相似文献   
192.
In recent years,bank credit business is booming with the increasing borrowing intention of China’s listed companies,and debt financing has become the major approach among listed companies’financing strategies.As a series of institutional arrangements about rights,responsibilities and benefits between different shareholders,corporate governance mechanism has a significant influence on the cost of debt financing.This paper employs variable coefficient panel data model to investigate the relationship of the listed company’s debt financing costs and corporate governance mechanism in terms of structural characteristics and time series characteristics.The results show that optimizing the structure of both Board of Directors and Board of Supervisors,establishing a reasonable management incentive system and reducing the concentration of ownership properly can directly contribute to a lower company’s debt financing costs.Meanwhile,property rights have an interactive influence on corporate governance from four aspects,which indirectly effect in company’s debt financing costs.  相似文献   
193.
This paper introduces a generalized multivariate Gumbel (GMG) distribution using a survival copula. Various dependence properties of the GMG distribution and some analytical properties of the generators of the GMG distribution are studied. Furthermore, the authors also investigate the dependence behavior of the residual lifetime vector of the GMG distribution. As an illustration, the GMG distribution is applied to fit a real data set.  相似文献   
194.
This article presents a general form of the estimator for identifying dispersion effects from unreplicated two-level factorial experiments, and shows that the widely used estimators such as the BH, MH, and AMH estimators are all special cases of the proposed one, designated as the G estimator. The unbiased condition of the G estimator is proved, and a lower bound of variance of the G estimator is provided. A simulation based on a realistic design illustrates the variation of the variance and MSE (mean square error) of the G estimator on different coefficients. This estimator may be more flexible and has better performance than other methods such as the BH and MH estimators by appropriately selecting the coefficients.  相似文献   
195.
带有参数的数据包络分析C~2R模型   总被引:1,自引:1,他引:1  
本文为了改进C~2R模型反映决策单元相对信息不完全的不足,提出了参数型数据包络分析模型,讨论了这个模型的有关性质,给出了阔值和有效值的概念.经过理论分析和实例验证,这两个值可更好地反映决策单元的相对信息.  相似文献   
196.
用GPS和集群通信组成动态指挥调度系统   总被引:1,自引:0,他引:1  
GPS(全球定位系统)是应用广泛的定位、导航系统,集群通信系统是专用业务移动通信网发展的高级形式,将GPS与集群通信相结合组成动态指挥调度系统是一个实现车辆动态监控的优选方案。本文探讨了这种方案,给出了实验系统设计。  相似文献   
197.
本文分析了黑河水库水温、水质与黑河水库取水建筑物的关系。建立了黑河水库水库水量水质综合优化调度的动态确定性多目标非线性数学模型。并按逐次逼近的逐步优化法(PAPOA法)对数学模型进行求解计算。经分析计算证明,该数学模型概念清晰,结构合理,计算精度较高,且优化迭代计算速度快,占计算机内存量小,避免了动态多目标优化中的“维数灾”。可供规划、设计及管理等阶段在分层型综合利用的水库水量水质综合优化调度中使用。  相似文献   
198.
本文利用非光滑分析理论,采用公理化方法研究了非光滑情形下的动态协商对策问题,给出其Nash协商解的必要条件,并给予了严格的数学证明.  相似文献   
199.
Li  Yapeng  Deng  Ye  Xiao  Yu  Wu  Jun 《系统科学与复杂性》2019,32(6):1630-1640
To investigate the attack and defense strategies in complex networks, the authors propose a two-player zero-sum static game model with complete information which considers attack and defense strategies simultaneously. The authors assume that both the attacker and defender have two typical strategies: Targeted strategy and random strategy. The authors explore the Nash equilibriums of the attacker-defender game and demonstrate that when the attacker's attack resources are not so significantly abundant as the defender's resources, there exists a pure-strategy Nash equilibrium in both model networks and real-world networks, in which the defender protects the hub targets with large degrees preferentially, while the attacker prefers selecting the targets randomly. When the attack resources are much higher than defense resources, both the attacker and the defender adopt the targeted strategy in equilibriums. This paper provides a new theoretical framework for the study of attack and defense strategies in complex networks.  相似文献   
200.
Li  Wanxing  Long  Yonghong 《系统科学与复杂性》2019,32(6):1727-1746
This paper proposes a flexible additive-multiplicative Cox-Aalen hazard model which allows time-varying covariate effects for the subdistribution in a competing risks study. Weighted estimating equation approaches under an covariates-dependent adjusted weight by fitting the Cox proportional hazard model for the censoring distribution are established for inference on the model parametric and nonparametric components. In addition, large number properties are presented and the finite sample behavior of the proposed estimators is evaluated through simulation studies, estimators from the proposed method perform satisfactorily on reduction of the bias. The authors apply our model to a competing risks data set from a tamoxifen trail for breast cancer study.  相似文献   
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