The work presented in this article focuses on designing a disturbance-observer-based fixed-time controller for the quadrotor unmanned aerial vehicle (QUAV) system, which aims to research the attitude control issues of QUAV with state constraints and external disturbances. Firstly, a novel controller depend on adding one power integrator and fixed-time control technique is introduced to implement finite time convergence regardless of original states. Then, the external disturbances of QUAV system are estimated via the disturbance observer. Futhermore, the proposed method is demonstrated to be fixed-time stable through barrier Lyapunov analysis. In the end, theoretical results are also illustrated and supported by simulation studies.

This paper proposes a robust trajectory tracking control strategy based on the high-order fully actuated system approach and disturbance observer. In spite of the strong coupling characteristic and high nonlinearity of the quadrotor unmanned aerial vehicle (QUAV) system, the linear time-invariant system with desired eigenstructures can be obtained by designing a greatly simple robust controller via the direct parametric method. Meanwhile, a disturbance observer (DO) is designed to estimate the external disturbances, and the output of the DO can be adapted for the controller design to compensate for the affect of external disturbances on control performance. Eventually, the numerical simulation results of the QUAV trajectory tracking demonstrate the effectiveness of the developed robust control scheme.

In this paper, an asynchronous advantage actor-critic (A3C) based intelligent temperature control method is proposed for Continuous Stirred Tank Reactor (CSTR) system. Firstly, the overall framework of CSTR system is composed of global network, thread network, environment model and interaction mechanism is designed. Secondly, the process of interaction is designed: the thread network is trained to interact with environmental models by using an asynchronous multi-threaded approach, the trained parameters are updated and synchronized to the global network. Finally, the effectiveness and stability of A3C algorithm is verified by the simulation experiments. The simulation experiments show that the trained A3C network can control the output temperature of the CSTR system to reach the preset temperature and keep it the preset temperature, so the temperature control of the CSTR system is achieved in the A3C algorithm.

针对一类具有未知外部干扰和系统不确定性的两级化学反应器系统,提出了一种基于干扰观测器的回馈递推跟踪控制方案.首先根据两级化学反应器的实际反应过程,建立严格反馈非线性系统模型,将系统反应过程中的未知外部干扰和系统不确定视为复合干扰,设计一种非线性干扰观测器估计复合干扰,并将干扰观测器输出用于控制器设计;进而利用回馈递推控制技术,设计两级化学反应器系统鲁棒控制方案,使系统实际输出跟踪上期望的参考信号,并通过Lyapunov稳定性理论分析闭环系统信号的有界稳定性;最后通过对两级化学反应器系统进行数值仿真实验,验证所提出跟踪控制方案的有效性.

With the development of computer network, the demand of real-time data processing is growing rapidly, and various processing schemes are blossoming.The problem that the demand of various industries, enterprises and institutions for real-time data processing, and its current project development methods and supporting tools are not compatible is gradually highlighted. Therefore, through flume technology, with the use of Ali cloud products,this paper achieve a real-time business processing scheme.from the direction of data stream - data source, data collection, cache queue, real-time processing calculation and data display four directions.

In this paper, considering the simultaneous influence of multi-source disturbances, system modeling uncertainties and input–output constraints, an adaptive robust attitude tracking control scheme is proposed for near space vehicles (NSVs) which is expressed as a stochastic nonlinear system. A multi-dimensional Taylor polynomial network (MTPN) is utilized to handle the system uncertainties, and the nonlinear disturbance observer (NDO) based on MTPN is designed to estimate the external disturbances. Furthermore, by constructing the auxiliary system to tackle the input saturation and introducing the Tan-type barrier Lyapunov function (TBLF) to solve the output constraint, the constrained control strategy can be obtained. Combining with backstepping control (BC) technique and stochastic control method, an adaptive robust stochastic control scheme is developed based on NDO, MTPN, and auxiliary system, and the closed-loop system stability in the sense of probability is analyzed based on stochastic Lyapunov stability theory. Finally, numerical simulations further demonstrate the feasibility of the proposed tracking control scheme.

In this paper, based on exponential Chebyshev (EC) polynomials, an approximation-based finite-time robust tracking control approach is proposed for MIMO stochastic nonlinear systems. To handle the unknown continuous functions, EC polynomials are utilized to estimate the unknown nonlinear functions with arbitrary precision. Combining with backstepping method, the finite-time robust stochastic controller is designed, and the designed control approach can ensure that all the closed-loop system signals are semi-global finite-time stable in probability (SGFSP). Consider the near space vehicles (NSVs) with stochastic input noise, the simulation results of the NSVs attitude motion show the effectiveness of the proposed approach.

随着云计算技术的发展,私有云越来越受到企业的追捧.访问控制管理技术是信息安全体系中不可或缺的组成部分,因此如何做好云计算环境下的访问控制就显得尤为重要.本文在对私有云和访问控制研究的基础上,提出了一种扩展的基于角色的访问控制模型,该模型引入了时效因子和信任因子的概念,通过对其二重认证,提高了访问控制的安全性.

目前,大部分业务支撑系统都配备应急管理系统以便于处理系统故障,但传统的应急系统都具有时间滞后的特点,实用的应急系统的开发必不可少.在阐述业务系统的现状、对应急切换管理的必要性进行分析的基础上提出了应急切换管理系统,并详细描述了应急切换管理系统的功能和关键技术,结合实验数据对系统进行了性能分析.应急切换管理系统创新性的实现了系统故障的自动检测和警告,实现了应急系统的自动切换以及系统故障趋势的预测预警.此外,该应急系统实现成本低,可以有效缩短应急系统的切换时间,减少或消除因系统故障带来的负面影响.

随着学院模块化教学改革的推进,对数学与应用数学专业(师范类)计算机类课程模块化改革进行总结探索.该文首先分析了数学与应用数学专业(师范类)计算机类课程的现状,描述了该专业计算机类课程模块框架,并对所负责模块《计算机基础及其应用模块I》和《计算机基础及其应用模块II》的构建思路及模块内容和考核方案等进行了探讨.

针对信息与计算科学专业特点、就业困境及应用型人才培养总体要求,以合肥学院为例,在人才培养方案调整与优化的基础上,对信息与计算科学专业实践教学体系进行了重建与创新.实践表明,实践教学体系的改革有效地培养了学生的实践能力和创新能力,提高了应用型人才培养质量.

在学院开展模块化教学改革的形势下，秉承培养应用型本科人才的办学定位，对数学专业计算机类课程模块化改革进行探索。本文分析了数学专业计算机类课程的现状，对模块课程进行合理转换，探讨了《程序设计》和《数据结构与算法》模块课程整合的思路及内容和考核方案等。

访问控制是信息网格安全机制的重要方面,它影响到网格系统中用户的操作行为.该文对信息网格及其访问控制的关键问题进行研究,通过分析信息网格的多管理域特点,进一步提出了一个基于函数的访问控制模型,从而解决跨域访问带来的安全性问题.

Information grid is a system which can utilize grid technology to implement the sharing and managing of the information resource,and supply the information services.In the information grid,the adoption of access control mechanism is effected and restricted by the characters of the information grid,that is multi—managing domain.In this article,we make a research on the key problems in the information grid accessing control.and through the analysis that information grid is characterized by the multi-managing domain,we show an accessing control model based on function,which can resolve security difficulties in accessing among managment domains.

Sharing of the resource in the information grid is implemented by access control which can give authorizations to users and the request of information service,the adoption of accesss control mechanism is effected by the character of the information grid--multi-managing domain.In this article, the important problems in information grid accessing control are presented in this article,and we analysis that information grid is characterized by the multi-managing domain, then give the problem of resource sharing among manage domain.At last,this article show a composite authorization and validation mechanism which can change the information dynamicly,which resolve difficulties that accessing among manage domain brings and predigest the operation of management.

A problem of private privileges that child role couldn't obtain because of inherited relation in the RBAC model of information grid was researched,two present resolvations that used private roles and deepness fist notes were analyzed,from which they could result in role inflate and compages explosion.Then a new resolvation with privilege transmit deepness was presented,that was,every privilege of the role could get public attributions,private attributions and a privilege transmit deepness.Meanwhile an algorithm to obtain privilege sets of each role was given.