Receding Horizon Estimation for Linear Discrete-time Systems with Multi-channel Observation Delays

This paper investigates the receding horizon state estimation for the linear discrete-time system with multi-channel observation delays. The receding horizon estimation is designed by the reorganized observation technique and the linear unbiased estimation method. The estimation gains are developed by solving a set of Riccati equations, and a stability result about the state estimation is shown. Finally, an example is given to illustrate the efficiency of the receding horizon state estimation.

Robust model predictive control for continuous uncertain systems with state delay

This paper is concerned with robust model predictive control for linear continuous uncertain systems with state delay and control constraints, A piecewise constant control sequence is calculated by minimizing the upper-bound of the infinite horizon quadratic cost function, At each sampling time, the sufficient conditions for the existence of the model predictive control are derived, and expressed as a set of linear matrix inequalities. The robust stability of the closed-loop svstems is guaranteed bv the proposed design method. A numerical example is given to illustrate the main results.

Determination and Evaluation of Heavy Metal Content of Freshwater Economic Fish in Northeast Guangdong

Concentrations of lead( Pb),cadmium( Cd),chromium( Cr),copper( Cu),zinc( Zn) and manganese( Mn) were measured in various organs( such as in liver and muscle) from 9 species of freshwater economic fishes which were collected from northeast area of Guangdong Province. The concentration of metals was measured by inductively coupled plasma atomic emission spectrometry( ICP- AES). Results showed that the levels of metals in hepatopancreas of the fishes were found in order of Zn > Pb > Cu > Hg > Cd,while in muscles were Zn > Cr> Pb > Mn > Cu > Cd. In general,the metals concentrations were significantly higher in liver samples than that in muscle samples. Based on the " pollution index of single factor",the fishes,to one degree or another,were polluted by Pb,Cd,Cr,Cu and Zn,and pollution levels were mostly followed by Pb > Cd > Cr > Cu > Zn. The indexes of Pb and Cd tested in hepatopancreas of the fishes were in a majority exceeded the national safety criteria for food in China. What's more,it was found that the contents of the heavy metals in fishes did not vary with the trophic level which they belong to. In summary,the fishes were polluted by Pb,Cd,Cr,Cu and Zn to some extent,which indicated that hidden danger of heavy metals pollution was present in ecological environment or safety in fishery production in the area.

ROBUST MODEL PREDICTIVE CONTROL OF CONTINUOUS UNCERTAIN SYSTEMS

作者使柔韧的模型担心为有 polytopic 不确定性和输入限制的线性连续系统的预兆的控制。在每采样时间，一片明智的经常的控制顺序被解决一套线性矩阵不平等获得。预兆的控制被给的模型的存在上的足够的条件，和靠近环的系统的柔韧的稳定性被保证。一个模拟例子说明建议方法的效率。

Optimal linear estimator for discrete-time systems with random delays

In this paper, optimal estimation for discrete-time linear time-varying systems with randomly state and measurement delays is considered. By introducing a set of binary random variables, the system is converted into the one with both multiplicative noises and constant delays. Then, an estimator which includes the cases of smoothing and filter- ing, is derived via the projection formula, and the solution is given in terms of a partial difference Riccati equation with boundary conditions. A predictor for such systems is also presented based on the proposed filter and smoother. The ob- tained estimators have the same dimension as the original state. Conditions for existence, uniqueness, and stability of the steady-state optimal estimators are studied for time-invariant cases. In this case, the obtained estimators are very easy to implement and all calculations can be performed off line, leading to a linear time-invariant estimator.