屈原生卒年考证

关于屈原生卒年,目前盛行"生于公元前340年,卒于公元前278年,享年62岁"的郭沫若说,笔者认为有误。笔者从屈原作品中重新推算,得出的结论为:生年为楚宣王二十七年,公元前343年,为戊寅年,卒年为顷襄王二十二年,享年六十六岁。     

电子文件时代文档管理一体化论

电子文件时代,信息化和网络化为新的档案管理观——文档管理一体化提供了必要的物质技术和理论实践基础。本文对文档管理一体化的理论基础、实践基础、主要障碍以及实现措施等方面进行了探讨。     

环环相扣--完善学位论文数据链

数据采集链的构建体系、功能和数据采集过程是学位论文全文数据库建设的一个重要方面.本文详解了学位论文全文数据采集链及数据采集过程的具体环节,通过特定项目的比较、定量分析,对数据采集总体效果作出了评价,进而探讨了完善数据采集链的有效方法和规范化渠道.     

高等学校学科建设内涵略析

本文从高等学校学科的两重属性和学科的内部结构出发,论述了高等学校学科建设的内涵。在学科管理层,学科建设主要包括学科组织建设、学科体系建设、学科要素建设和学科运行机制建设四个方面。     

学术期刊双向经营的探讨

根据我国学术期刊的经营状况,探讨学术期刊向读者提供产品(刊物)和向作者提供刊文服务的双向经营运行模式.作者刊文服务系根据学术期刊出版成本为核算基础的有偿服务,有利于缓解出版资源有限与日益增长的作者刊文需求之间的矛盾,调整作者与编辑的关系,改善学术期刊经营状况,更多更好地为作者服务.分析了作者服务经营的可行性.     

地学领域几个常见量符号的规范使用

介绍地学书刊中经常出现的同位素比值、同位素组成、元素及氧化物的质量分数、摩尔分数和物质的量含量等 5类量的含义 ,阐明这些量在表达及量符号使用上存在的问题 ,以及如何规范地使用量符号来表达这些量。认为提高地学书刊编辑人员的地学专业知识水平是解决存在问题并正确执行《量和单位》国家标准的关键     

Stabilization of a class of nonlinear parametrized systems by a flexible switching adaptive backstepping

In this paper, we consider global adaptive feedback control of nonlinear systems with unknown parameters entering nonlinearly. Such unknown parameters are also not required to lie in a known compact set. Unlike previous results, our proposed adaptive controller is a new double dynamical switching-type controller in which the controller parameter is tuned in a flexible switching manner via a monotonically decreasing switching logic and the controller combines the traditional adaptive theorem with the switching scheme perfectly. Global stability results of the closed-loop system have been proved.     

Semi-global leader-following coordination of multi-agent systems with input saturation and aperiodic intermittent communications

This paper addresses the semi-global leader-following coordination problem of general linear multi-agent systems, in which the control input of each agent is steered by aperiodically intermittent saturated actuator. Both the case with only one virtual leader and the case with multiple virtual leaders are discussed. By using multiple Lyapunov stability theory and applying algebraic Riccati equation-based low-gain feedback technique, sufficient conditions guaranteeing semi-global consensus tracking and semi-global containment tracking are provided. Numerical simulations finally verify the theoretical analysis.     

Output regulation for a class of positive switched systems

In this paper, a complete procedure for the study of the output regulation problem is established for a class of positive switched systems utilizing a multiple linear copositive Lyapunov functions scheme. The feature of the developed approach is that each subsystem is not required to has a solution to the problem. Moreover, two types of controllers and switching laws are devised. The first one depends on the state together with the external input and the other depends only the error. The conditions ensuring the solvability of the problem for positive switched systems are presented in the form of linear matrix equations plus linear inequalities under some mild constraints. Two examples are finally given to show the performance of the proposed control strategy.