Distributed Second-Order Continuous-Time Optimization via Adaptive Algorithm with Nonuniform Gradient Gains

Journal of Systems Science and Complexity - This paper addresses the distributed adaptive optimization problem over second-order multi-agent networks (MANs) with nonuniform gradient gains. A...     

Constrained Consensus of Continuous-Time Heterogeneous Multi-Agent Networks with Nonconvex Constraints and Delays

Journal of Systems Science and Complexity - This paper studies the continuous-time constrained consensus of heterogeneous multi-agent networks with nonconvex input and velocity constraints, where...     

Robust stabilization for multi-input polytopic nonlinear systems

This paper deals with the problem of the stabilization for multi-input polytopic nonlinear systems. Based on the robust control Lyapunov function, a sufficient condition for the existence of time-invariant, continuous, asymptotically stabilizing state feedback controller is derived. It is shown that the obtained sufficient condition is also necessary if there exists a state feedback controller such that the closed-loop system has a robust Lyapunov function for all possible uncertainties. Moreover, a universal formula for constructing stabilizing controller is proposed and the existence of the corresponding Lyapunov function is proven. Particularly, a Lyapunov function is constructed for the polytopic nonlinear system in canonical form. Finally, the feasibility of the proposed control law is verified by a numerical example.     

Consensus of Linear Multi-Agent Systems with Persistent Disturbances via Distributed Output Feedback

This paper addresses the consensus problem of general linear multi-agent systems with persistent disturbances by distributed output feedback. Suppose that states of agents can not be obtained directly. Several estimators are designed to observe states of agents and the unknown disturbances.A protocol is proposed to drive all agents achieve consensus. Based on the method of model transformation and the property of permutation matrix, sufficient conditions for consensus are obtained in terms of linear matrix inequalities. Finally, simulations are given to show the effectiveness of presented results.     

单性木兰幼苗与成年植株叶片光合功能及结构比较

为探究单性木兰（Kmeria septentrionalis）幼苗、成年植株叶片结构和光合特性的差异情况以及内在联系,揭示单性木兰叶片结构对光合速率的影响规律,本研究采用Li-6400便携式光合仪测定单性木兰幼苗和成年植株叶片的光合-光响应曲线,并通过电镜扫描比较其幼苗和成年植株叶面解剖特征的差异。结果表明：单性木兰成年植株的净光合速率显著高于幼苗;最大净光合速率（P_max）和光饱和点（LSP）存在显著性差异;成年植株对强光的利用能力高于幼苗,而幼苗较成年植株有更好的弱光利用能力;幼苗和成年植株的总叶绿素[Chl（a+b）]、类胡萝卜素（Car）、叶片厚度（LT）、气孔面积（SA）、气孔密度（SD）、栅栏组织厚度（PPT）和气孔横轴长度（SW）均存在显著性差异;Car、Chl（a+b）、SA和SD对光合生理特性的影响最为显著。因此,建议在单性木兰的引种栽培中,将幼苗进行遮阴处理,随着植株生长可适当减小遮阴度,待植株成年后可不做遮阴处理。     

企业主导的某境外工程项目非传统安全应急处置案例研究

"一带一路"背景下,我国企业积极参与"一带一路"沿线各国的经济合作和工程建设,业务分布广、参与人员众多。相应地,境外工程项目各类安全风险问题也随之凸显。本文以境外某项目"4.26"突发应急事件发生后,企业自身组织开展的应急撤离为例,探索应急处置体系在境外工程项目非传统安全领域的应用。尤其是与国家主导的、军事参与的境外非传统安全应急工作相比,对国内企业自我主导建立境外项目应急体系更具有参考价值。