Static output feedback control for discrete-time fuzzy bilinear system

The problem of designing fuzzy static output feedback controller for T-S discrete-time fuzzy bilinear system （DFBS） is presented. Based on parallel distribution compensation method, some sufficient conditions are derived to guarantee the stability of the overall fuzzy system. The stabilization conditions are further formulated into linear matrix inequality （LMI） so that the desired controller can be easily obtained by using the Matlab LMI toolbox. In comparison with the existing results, the drawbacks, such as coordinate transformation, same output matrices, have been elim- inated. Finally, a simulation example shows that the approach is effective.

Studies on Composting Spent Coffee Grounds by <i>Aspergillus sp</i>and <i>Aspergillus sp</i>in Aerobic Static Batch Temperature Control

Spent Coffee Ground (SCG) is characterized by high organic content, in the form of insoluble polysaccharides bound and phenol compounds. Phenol compounds are toxic to nature and are a cause of environmental pollution. Composting method of this study is aerobic static batch composting with temperature control with adding activators of some fungi such as Aspergillus sp, and Penicillium sp. The purpose of the research is to fill the research gap from previous studies of spent coffee grounds compost, which requires a long time in composting, so that if it is used directly on the soil and plants, the positive effect also requires a long time. The result of composting for 28 days with this method is that mature compost has black crumb and normal pH, with characteristics of C/N ratio below 10: C1 (7.06), C2 (6.99). This value is far from the control with a C/N ratio of 8.33. Decompose rate of macromolecule are above 40% for lignin and 70% for cellulose. Implementation of compost in radish plants, resulting Germination Index above 80% which indicates that the compost is ripe: control (92.39%), C1 (183.88%), C2 (191.86%). The results of the analysis with FTIR also showed that the compost was mature and stable, and rich in minerals. So, it can be concluded that this composting method can speed up composting time and optimize the results of compost produced.

Static shape control of a flat shell structure

The eight-node and forty-DOF piezoelectric shell element were applied to shape control of a flat shell structure. By the direct and converse effects, a distributed piezoelectric sensor layer was used to monitor the shape deformation and a distributed actuator layer was used to suppresse the deflection. A finite element model was for static response of laminated shell with piezoelectric sensors/actuators was derived. The model was verified by calculating piezoelectric polymeric PVDF bimorph beam. The results are in good agreement with those obtained by theoretical analysis of Tzou and Hwang . A case study of the static shape control of a flat shell structure is presented.

Robust H_∞ and H_2 Static Output Feedback Control of Discrete-time Piecewise Affine Singular Systems with Norm-bounded Uncertainties

This paper is concerned with the problem of designing robust H∞and H2static output feedback controllers for a class of discrete-time piecewise-affine singular systems with norm-bounded time-varying parameters uncertainties. Based on a piecewise singular Lyapunov function combined with S-procedure,Projection lemma and some matrix inequality convexifying techniques,sufficient conditions in terms of linear matrix inequalities are given for the existence of an output-feedback controller for the discrete-time piecewiseaffine singular systems with a prescribed H∞disturbance attenuation level,and the H2norm is smaller than a given positive number. It is shown that the controller gains can be obtained by solving a family of LMIs parameterized by one or two scalar variables. The numerical examples are given to illustrate the effectiveness of the proposed design methods.

Output Feedback Controller Design for Discrete-time Switched Singular Systems

This paper is concerned with the problems of robust admissibility and static output feedback( SOF)stabilization for a class of discrete-time switched singular systems with norm-bounded parametric uncertainties.The objective is to design a suitable robust SOF controller guaranteeing the regularity,causality and asymptotic stability of the resulting closed-loop system under arbitrary switching laws. Based on the basic matrix inequality sufficient condition for checking the admissibility of switched singular systems,together with some matrix inequality convexifying techniques,the SOF controller synthesis is developed for the underlying systems. It is shown that the controller gains can be obtained by solving a set of strict linear matrix inequalities( LMIs). A simulation example is given to show the effectiveness of the proposed method.

GPS-RTK在线路测量中的应用研究

为了解决在道路放样测量中点位精度低的问题,在哈伊公路庆安到绥化段(公里桩号为K165+150至203+950)的线路测量中,采用GPS RTK技术进行放样路线上的点位,并采用了RTK测量高程,同时使用普通水准测量的方法对所放出的点位进行水准测量,进行精度对比分析无论是平面还是高程都取得了令人满意的效果。本文主要结合工程实际阐述了GPS在工程控制测量、RTK技术放样过程的应用及效果,并对GPS高程测量精度的进行分析比较,总结了GPS在线路工程应用中的经验,为相关工程应用提供借鉴。

Decentralized Networked Control System Design Using Takagi-Sugeno(TS) Fuzzy Approach

This paper proposes a new method for control of continuous large-scale systems where the measures and control functions are distributed on calculating members which can be shared with other applications and connected to digital network communications.At first, the nonlinear large-scale system is described by a Takagi-Sugeno(TS) fuzzy model. After that, by using a fuzzy LyapunovKrasovskii functional, sufficient conditions of asymptotic stability of the behavior of the decentralized networked control system(DNCS),are developed in terms of linear matrix inequalities(LMIs). Finally, to illustrate the proposed approach, a numerical example and simulation results are presented.

Secure control for discrete-time hidden Markov jump systems subject to replay attacks via output feedback

This paper investigates the static output feedback secure control problem for discrete-time hidden Markov jump systems against replay attacks. The main purpose is to realise that closed-loopsystems are stochastically stable with or without replay attacks. Firstly, the tampered sensorsunder replay attacks can be identified via the proposed detection method. Then, an asynchronousstatic output feedback controller is designed, which can eliminate the negative impactcaused by replay attacks in view of the detection results. Based on the linear matrix inequalitytechnique, some sufficient conditions which ensure the closed-loop systems are stochasticallystable and meet a given H∞ performance are established. Finally, a numerical example and apractical example are given to verify the effectiveness and superiority of the proposed method.

Design and evaluation of control strategies in urban drainage systems in Kunming city

Real time control （RTC） of urban drainage systems （UDSs） is an important measure to reduce combined sewer overflow （CSO） and urban flooding, helping achieve the aims of ＂Sponge City＇. Application of RTC requires three main steps： strategy design, simulation-based evaluation and field test. But many of published RTC studies are system-specific, lacking discussions on how to design a strategy step by step. In addition, the existing studies are prone to use hydrologic model to evaluated strategics, but a more precise and dynamic insight into strategy performance is needed. To fill these knowledge gaps, based on a case UDS in Kunming city, a studio on RTC strategy design and Management Model （SWMM） - uncier four typical rainfall events characterized by different return periods （1-year or 0.5 year） and different spatial distributions （uniform or uneven）. The equal filling strategy outperformss other two strategies and it can achieve 10% more CSO reduction and 5% more flooding reduction relative to the no-tank case.