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91.
92.
Xiaoxiang Hu Changhua Hu Zhaoqiang Wang Huijun Gao 《International journal of systems science》2014,45(8):1740-1756
By utilising Takagi–Sugeno (T–S) fuzzy set approach, this paper addresses the robust H∞ dynamic output feedback control for the non-linear longitudinal model of flexible air-breathing hypersonic vehicles (FAHVs). The flight control of FAHVs is highly challenging due to the unique dynamic characteristics, and the intricate couplings between the engine and fight dynamics and external disturbance. Because of the dynamics’ enormous complexity, currently, only the longitudinal dynamics models of FAHVs have been used for controller design. In this work, T–S fuzzy modelling technique is utilised to approach the non-linear dynamics of FAHVs, then a fuzzy model is developed for the output tracking problem of FAHVs. The fuzzy model contains parameter uncertainties and disturbance, which can approach the non-linear dynamics of FAHVs more exactly. The flexible models of FAHVs are difficult to measure because of the complex dynamics and the strong couplings, thus a full-order dynamic output feedback controller is designed for the fuzzy model. A robust H∞ controller is designed for the obtained closed-loop system. By utilising the Lyapunov functional approach, sufficient solvability conditions for such controllers are established in terms of linear matrix inequalities. Finally, the effectiveness of the proposed T–S fuzzy dynamic output feedback control method is demonstrated by numerical simulations. 相似文献
93.
D.J. Progar 《International Journal of Adhesion and Adhesives》1984,4(2):79-86
An adhesive-bonding process cycle study was performed for a polyimidesulphone. The high molecular weight, linear aromatic system possesses properties which make it attractive as a processable, low-cost material for elevated temperature applications. The results of a study to better understand the parameters that affect the adhesive properties of the polymer for titanium alloy adherends are presented. These include the tape preparation, the use of a primer and press and simulated autoclave processing conditions. The polymer was characterized using Fourier transform infrared spectroscopy, glass transition temperature determination, flow measurements, and weight loss measurements. The lap shear strength of the adhesive was used to evaluate the effects of the bonding process variations. 相似文献
94.
《Journal of Systems Architecture》2014,60(10):783-795
Complex systems on chip containing dozens of processing resources with critical communication requirements usually rely on the use of networks on chip (NoCs) as communication infrastructure. NoCs provide significant advantages over simpler infrastructures such as shared busses or point to point communication, including higher scalability, more efficient energy management, higher bandwidth and lower average latency. Applications running on NoCs with more than 10% of bandwidth usage attest that the most significant portion of message latencies refers to buffered packets waiting to enter the NoC, whereas the latency portion that depends on the packet traversing the NoC is sometimes negligible. This work presents an adaptive routing architecture, named Monitored NoC (MoNoC), which is based on a traffic monitoring mechanism and the exchange of high priority control packets. This method enables to adapt paths by choosing less congested routes. Practical experiments show that the proposed path adaptation is a fast process, enabling to transmit packets with smaller latencies, up to 9 times smaller, by using non-congested NoC regions. 相似文献
95.
96.
物联网技术作为一项新兴的技术,已经成为了研究人员研究的热点。智能家居作为物联网的一个重要的分支,几年来发展迅猛,为人们提供了理想的家居环境。人们追求更加理想的生活环境,为了满足人们的追求,我们设计了一款基于zigbee技术的智能化窗帘。该系统是基于zigbee技术的的一款可以无线通信的智能化窗帘。采用的是TI公司的cc2530的zigbee片上应用系统。通过无线传输技术、传感技术等实现窗帘的智能控制。 相似文献
97.
介绍了利用多CPU来设计整流控制器,解决大功率整流装置产生的磁场对整流计算机控制系统产生的干扰。 相似文献
98.
阐述了在D级压力容器制造许可证取换证鉴定评审过程中,取换证制造企业存在的较为普遍的问题。 相似文献
99.
《Journal of Process Control》2014,24(12):7-17
In the presence of rate constraints in actuator, design of cascade controller based on the primary controller conditional integration can result into closed-loop system oscillations. Stability analysis, performed by the describing function technique and confirmed by simulation, demonstrates that the solution based on the Anti-Reset Windup Cascade Control System (ARW CCS) structure is successful. Design and tuning of the ARW CCS secondary controller is a standard ARW single-input single-output problem. In the present paper tuning is proposed for the ARW CCS primary controller. For the serial process modeling simple rules are derived and confirmed by experimental results, obtained on a drum type boiler of a 210 MWe lignite coal fired unit. General design of the ARW CCS is based on the parallel process modeling and optimization of the primary controller. Optimization is performed in the frequency domain, under constraints on the maximum sensitivity, multiplicative uncertainty bound and sensitivity to measurement noise. Simulation and experimental results on a laboratory thermal plant demonstrate effectiveness of the proposed optimization. 相似文献
100.