ROBUST RELIABLE CONTROLLER DESIGN FOR A CLASS OF TIME-VARYING UNCERTAIN SYSTEMS

The normal H ∞ control design deals with both plant modeling uncertainties and exogenous signal uncertainties by constructing a controller which stabilizes uncertain li near systems while satisfying an H ∞ norm bound constraint on disturbance attenuation for all admissible uncertainties. However, the control design may result in unsatisfactory performances or even instabilities in the event of sensor failures in practical plants. This paper focuses on the problem of the design of robust reliable H ∞ control for a class of time varying uncertainty system with sensor failures. The paper presents a novel technique which deal with this problem by solving three linear matrix inequalities (LMIs). The strict proof guarantees the feasibility of this approach.

Highly Effective Detection of Amitraz in Honey by Using Surface-Enhanced Raman Scattering Spectroscopy Coupled with Chemometric Methods

As an effective and universal acaricide, amitraz is widely used on beehives against varroasis caused by the mite Varroa jacobsoni. Its residues in honey pose a great danger to human health. In this study, a sensitive, rapid, and environmentally friendly surface-enhanced Raman spectroscopy method (SERS) was developed for the determination of trace amount of amitraz in honey with the use of silver nanorod (AgNR) array substrate. The AgNR array substrate fabricated by an oblique angle deposition technique exhibited an excellent SERS activity with an enhancement factor of -10^7. Density function theory was employed to assign the characteristic peak of amitraz. The detection of amitraz was further explored and amitraz in honey at concentrations as low as 0.08 mg/kg can be identified. Specifically, partial least square regression analysis was employed to correlate the SERS spectra in full-wavelength with Camitraz to afford a multiple-quantitative amitraz predicting model. Preliminary results show that the predicted concentrations of amitraz in honey samples are in good agreement with their real concentrations. Compared with the conventional univariate quantitative model based on single peak’s intensity, the proposed multiple-quantitative predicting model integrates all the characteristic peaks of amitraz, thus offering an improved detecting accuracy and anti-interference ability.

Robust Adaptive FTC against Sensor Fault

This paper addresses the problem of robust Fault-Tolerant （FT） design for large-scale systems. This particular class constitutes complex system which can be decomposed into N-interconnected subsystems. Special attention is paid to two different design architectures of an Active Fault-Tolerant Control （AFTC）. An AFTCS is characterized by an online Fault Detection and Isolation （FDI） process and a control reconfiguration mechanism. As the AFTC system offers the possibility to choose different controllers, the controller may be the most appropriate choice for the faulty situation and obtaining better performance. The goal of each adaptive controller is to accommodate sensor anomalies. Continuous, Linear and Time Invariant （LTI） complex system with faulty sensors and external disturbances is proposed. This study focuses on two different internal structures of the system. In this paper the direct adaptive method based on feedback controller design is applied both centralized and decentralized architectures. The controller gain is updated online using an adaptive law which takes into account the estimation of the faults and the disturbances. Then from the both classes of systems structures the adaptation controller performances, in terms of stability and fault effect rejection capability, are studied and compared. The proposed techniques are finally evaluated in the light of a simulation for a centralized interconnected system that can be decomposed into N-subsystems with some strong interconnections.

镜头前,我即主角! 正能量超人丁沛桐

比起丁沛桐这个名字,朋友更喜欢称他丁丁。喜欢潮流,热衷自己热爱的事物,不被外界所左右。身兼数职,但每天仍能精力充沛出现在每个人面前。喜欢硬朗的铆钉装饰,也爱色彩斑斓的饰品以及柔软的长毛兔……在生活中的每一面都有丁丁精彩的演绎,只要在镜头前,他即是夺目主角。

丁沛桐 人类需要柔软

喜欢硬朗的铆钉装饰,也爱色彩斑斓的饰品以及柔软的长毛兔。丁沛桐在时尚达人的道路上步幅逐渐加快,期待他成为下一个被国际认识的中国街拍达人。1我害怕它突然消失因为工作忙,我没有喂养狗狗,只养了一只长毛兔。但是会帮助邻居照顾一只金毛寻回猎犬,对我和狗狗来说最惊险的,有一次带它出去散步时它突然跑开,一下子不见了……趁着夜色我找了好久,心惊胆战。对外界我们总习惯展露内心坚硬的一面,但面对狗狗,似乎才有特别真实的触动。

Robust high-resolution beam-forming based on high order cross sensor processing method

In order to obtain the robust high-resolution beamforming, a high order cross sensor processing(CSP) approach is developed. According to the relation ship between the target bearing and the phase difference of each element receiving signal, this method exploits the property that the same diagonal of covariance matrix with the same phase difference and obtains(2M-1)(N-1)virtual elements(N is the original array number) by executing M order CSP. The extended virtual elements can effectively increase the physical aperture of linear array, reduce the main lobe width of beam-forming, and improve the bearing resolution. The CSP method accumulates the data on the same sub-diagonal of the covariance matrix, which can decrease the impact of background noise on beam-forming. The theoretical analysis and experimental results both show that this method has high resolution in bearing estimation, compared with the MUSIC method, which has better robustness under the lower signal-to-noise ratio(SNR).

A novel robust design method for the sense mode of a MEMS vibratory gyroscope based on fuzzy reliability and Taguchi design

This paper proposes a novel robust design method for the sense mode of a MEMS vibratory gyroscope based on fuzzy reliability and Taguchi design. The principles of fuzzy reliability and Taguchi design are both introduced and described in detail. Experimental results demonstrate that the signal to noise ratio of the robust design scheme is better than those of the other experimental schemes.Over the full temperature range from -40 to 80°C, the temperature sensitivities of phase margin, gain margin, sensitivity margin,the maximum amplitude of open loop system, bandwidth of closed loop system, and the performance function of the robust design system are all smaller than those of the original design system. Meanwhile, the temperature sensitivity of the bandwidth of the robust design system is improved to 126 from 1075 ppm/°C. Moreover, the bias drift over the full temperature range of the robust design system is improved to 61°/h from 179°/h.

Oseltamivir decorated gold nanorods for visible rapid detection of influenza virus

In the present study,we developed a novel colorimetric strategy for the visible rapid detection of the influenza virus based on the unique optical properties of gold nanorods.Specifically,lipoic acid-modified Oseltamivir(OS),which is a strong neuraminidase inhibitor and used as the first-line drug in the treatment of influenza,was synthesized and further attached to the surface of gold nanorods(OS-LA-GNRs).The absorption band and density of OS-LA-GNRs were changed with the decreasing distance between the nanoparticles induced by the target-specific aggregation via strong neuraminidase–OS binding.All of these could be visible with the naked eyes and measured by UV-visible spectrophotometry.The results showed that our system had a comparable limit of detection(LOD)to the commercial colloidal gold stripes,making it feasible for wide diagnostic applications.