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81.
提出了电弧炉电极调节系统的数学模型 ,并在此模型基础上推导出了离散时间模型参考自适应控制规律。然后根据推导出的自适应律对电弧炉系统进行仿真研究 ,仿真结果表明自适应控制系统具有较好的跟踪性能。 相似文献
82.
The problem of channel sharing by rate adaptive streams belonging to various classes is considered. Rate adaptation provides
the opportunity for accepting more connections by adapting the bandwidth of connections that are already in the system. However,
bandwidth adaptation must be employed in a careful manner in order to ensure that (a) bandwidth is allocated to various classes
in a fair manner (system perspective) and (b) bandwidth adaptation does not affect adversely the perceived user quality of
the connection (user quality). The system perspective aspect has been studied earlier. This paper focuses on the equally important
user perspective. It is proposed to quantify user Quality of Service (QoS) through measures capturing short and long-term
bandwidth fluctuations that can be implemented with the mechanisms of traffic regulators, widely used in networking for the
purpose of controlling the traffic entering or exiting a network node. Furthermore, it is indicated how to integrate the user
perspective metrics with the optimal algorithms for system performance metrics developed earlier by the authors. Simulation
results illustrate the effectiveness of the proposed framework.
Nikos G. Argiriou received the Diploma degree in Electrical Engineering from the Department of Electrical Engineering, Telecommunication Division, Aristotle University of Thessaloniki, Greece, in 1996. He worked as a researcher, on secure medical image transmission over networks, at the Image Processing Lab at the same university during 1996–1997. During 1998–2000 he was a researcher for the European Project Esprit Catserver concerning the use of advanced Quality of Service techniques in CATV networks. He received his Ph.D. degree at Aristotle University of Thessaloniki in 2007. His current research interests are in the development and implementation of QoS techniques for wired and wireless networks. Leonidas Georgiadis received the Diploma degree in Electrical Engineering from Aristotle University, Thessaloniki, Greece, in 1979, and his M.S. and Ph.D degrees both in Electrical Engineering from the University of Connecticut, in 1981 and 1986, respectively. From 1986 to 1987 he was Research Assistant Professor at the University of Virginia, Charlottesville. In 1987 he joined IBM T. J. Watson Research Center, Yorktown Heights as a Research Staff Member. Since October 1995, he has been with the Telecommunications Department of Aristotle University, Thessaloniki, Greece. His interests are in the area of wireless networks, high speed networks, routing, scheduling, congestion control, modeling and performance analysis. 相似文献
Leonidas GeorgiadisEmail: |
Nikos G. Argiriou received the Diploma degree in Electrical Engineering from the Department of Electrical Engineering, Telecommunication Division, Aristotle University of Thessaloniki, Greece, in 1996. He worked as a researcher, on secure medical image transmission over networks, at the Image Processing Lab at the same university during 1996–1997. During 1998–2000 he was a researcher for the European Project Esprit Catserver concerning the use of advanced Quality of Service techniques in CATV networks. He received his Ph.D. degree at Aristotle University of Thessaloniki in 2007. His current research interests are in the development and implementation of QoS techniques for wired and wireless networks. Leonidas Georgiadis received the Diploma degree in Electrical Engineering from Aristotle University, Thessaloniki, Greece, in 1979, and his M.S. and Ph.D degrees both in Electrical Engineering from the University of Connecticut, in 1981 and 1986, respectively. From 1986 to 1987 he was Research Assistant Professor at the University of Virginia, Charlottesville. In 1987 he joined IBM T. J. Watson Research Center, Yorktown Heights as a Research Staff Member. Since October 1995, he has been with the Telecommunications Department of Aristotle University, Thessaloniki, Greece. His interests are in the area of wireless networks, high speed networks, routing, scheduling, congestion control, modeling and performance analysis. 相似文献
83.
针对某型涡轴发动机燃油调节器试验台定制开发了CAT系统;该系统是根据试验要求,结合当前先进的计算机测控技术,利用基于虚拟仪器技术的VXI总线数据采集系统,采用PID闭环控制模式,设计实现了集信号采集、过程控制、数据分析、记录存贮等多功能为一体的测控系统,具有工作稳定可靠、操作简单、维护方便等特点;实际应用表明,该系统满足该试验的技术要求,运行良好。 相似文献
84.
基于PI控制律的通用递阶模糊控制器 总被引:1,自引:0,他引:1
为解决常规模糊控制器存在的通用性和工程简便性问题,针对动态特性随操作条件变化对象建立自适应递阶模糊控制器,实现闭环模糊增益调度,并引入稳定监督控制使控制系统具有工程稳定性。 相似文献
85.
阐述了国产矿井提升机PC电控系统的发展过程及现状 ,指出了其没有完全实现PC化的主要原因 ,并提出了使其完全PC化的对策。最后 ,介绍了提升机制动系统用PC控制的实现方法。 相似文献
86.
A novel inner loop sliding mode current control scheme for induction motor speed drives is proposed in this paper. The controller design is based on the nonlinear mathematical model of an induction motor in a coordinate system oriented along the rotor flux. The parameters of the PI speed controller are taken into consideration in the inner loop sliding mode current control. Rigorous stability verification for the overall system is provided in this paper. The chattering in sliding mode control is attenuated using the reaching law design method. The experimental results show that the proposed approach exhibits robust tracking performance in the presence of motor parameter variations and load disturbances. 相似文献
87.
介绍电动汽车充电系统对电网的谐波影响.采用三电平PWM整理器对谐波进行抑制,设计电压电流双闭环的三电平PWM整流电路.分别对输出直流电压和输入电网电压和电流采样,经过PI调节器控制,使输出电压波形稳定,并使电网侧电流和电压达到基本同相,从而减小充电机对电网的谐波影响,提高单位功率因数. 相似文献
88.
实时数据库PI是电厂厂级监控信息体系常用的非关系型实时数据库,其数据存储量大,信息量丰富完整.大量的冗余信息、非关系型的数据存储方式等特点,给工业管理应用带来了数据信息采集和数据处理等各方面的问题.本文以P1实时数据为数据采集源,采用基于分层、模块化的软件体系架构,对实时数据库数据采集处理流程进行功能模块划分、设计和实现.针对客户相关需求,设计了极值采集算法,并在系统完成之后,连接电厂正在运行的PI实时数据库进行了实际测试,根据测试结果进行了性能方面的调整改进.从系统的运行结果来看,解决了以PI实时数据库为数据采集源的二次开发应用中所出现的问题,满足了工业管理应用方面的需求. 相似文献
89.
基于前馈控制的交流伺服系统精确定位的研究 总被引:2,自引:0,他引:2
介绍了交流伺服电动机数学模型,叙述了伺服控制系统的设计原理和具体方法,在位置环、速度环和电流环的3环PI伺服控制系统的基础上,引进位置前馈控制来提高定位控制的性能,研究了前馈PI的控制方法.通过仿真进行了与普通伺服控制系统的对比,未加前馈控制跟踪误差较大,在位置环加前馈控制恒速段跟踪误差较小,但在加减速度段,误差成单调变化,在速度环上再加上前馈控制,位置跟踪误差会更接近于零.结果表明,引进前馈控制的PI交流伺服系统可以实现高精度位置控制,验证了前馈控制在指令信号跟踪性和抗干扰性方面的良好效果. 相似文献
90.
从巨型机组励磁系统设备维护的经济性、技术服务的快捷性、设备升级改造的方便性以及对核心控制技术的可控性等方面考虑,龙滩水电站机组励磁系统的国产化改造显得尤为迫切。对龙滩水电站700MW机组励磁系统进行了国产化改造,介绍了改造实现方法和相关新技术的应用。 相似文献