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This note deals with the robust stability analysis for time-delay systems with nonlinear perturbations. Firstly, a new class of Lyapunov functional candidate is proposed to develop some new criteria by considering the additional useful terms and introducing some free-weighting matrices. Then, an augmented Lyapunov functional is introduced to establish a novel improved stability condition. All results obtained are given in terms of linear matrix inequalities. A numerical example is given to illustrate the effectiveness of the proposed methods.

A method for measuring the angle of two elements separated at a large distance by using a common optical reference is proposed. A common light plane or several parallel light planes are projected on these elements. The angles between these elements and the projections of light planes are measured and thereafter the angle between these two elements is determined. A practical example of measuring the angle formed by two elements separated at a distance of 7 m is shown. Its calibration method is also discussed.

This paper studies output feedback stabilization of networked control systems (NCSs) with random delays and random sampling periods. Sampling periods can random switch in three cases according to the high, low and medium three types of network load. The sensor-to-controller (S-C) random delays, controller-to-actuator (C-A) random delays and random sampling periods are modeled as three different Markov chains, respectively. A three-mode-dependent output feedback controller is designed, which depends on not only the current S-C delay but also the most recent available sampling period and the most recent available C-A delay at the controller node. An example is given to illustrate the effectiveness of the result.

The state-of-the-art image retrieval method pays more attention to the local region feature. This chapter proposes an algorithm to extract texture feature based on Laws’ filter. This algorithm performs texture transformation to an image and selects the region of interest. It convolves the input image with Laws’ filter mask. As to the filter mask, this chapter selects a five dimension vector and produces a 5 × 5 matrix as the filter kernel. The experiment shows that the algorithm has high speed and high accuracy in the segmentation process for image retrieval and confirms that it is effective for image retrieval based on the region of interest.

Compressive sensing in seismic signal processing is a construction of the unknown reflectivity sequence from the incoherent measurements of the seismic records. Blind seismic deconvolution is the recovery of reflectivity sequence from the seismic records, when the seismic wavelet is unknown. In this paper, a seismic blind deconvolution algorithm based on Bayesian compressive sensing is proposed. The proposed algorithm combines compressive sensing and blind seismic deconvolution to get the reflectivity sequence and the unknown seismic wavelet through the compressive sensing measurements of the seismic records. Hierarchical Bayesian model and optimization method are used to estimate the unknown reflectivity sequence, the seismic wavelet, and the unknown parameters (hyperparameters). The estimated result by the proposed algorithm shows the better agreement with the real value on both simulation and field-data experiments.

Multi-objective programming with uncertain information has been widely applied in modeling of industrial produce and logistic distribution problems. Usually the expectation value model and chance-constrained model as solution models are used to deal with such uncertain programming. In this paper, we consider the uncertain programming problem which contains random information and rough information and is hard to be solved. A new solution model, called stochastic rough multi-objective synthesis effect (MOSE) model, is developed to deal with a class of multi-objective programming problems with random rough coefficients. The MOSE model contains expectation value model and chance-constrained model by choosing different synthesis effect functions and can be considered as an extension of crisp multi-objective programming model. Combined with genetic algorithm, the optimal solution of the MOSE model can be obtained. It shows that the solutions of the MOSE model are better than that of other solution models. Finally, an illustrative example is provided to show the effectiveness of the proposed method.

In this paper, finite time leader-following consensus problem is discussed for multiple non-holonomic mobile agents. A novel distributed switching control strategy is proposed to guarantee finite-time leader-follower consensus of the multiple non-holonomic mobile agents with the help of time-rescalling technique, finite time Lyapunov theory and graph theory. The states of all the non-holonomic mobile follower agents can be made to reach consensus with the leader by tuning the time-rescalling parameters within any given finite setting time. The numerical simulations are presented to show the effectiveness of the given finite time consensus algorithms.

Constrained optimization problems widely exist in real world applications. A popular method to solve the problems is to transform the constraints to additional objectives and then the transformed problems can be solved by the multiobjective optimization techniques. The original multiobjective optimization techniques, such as Pareto dominance, lack the search bias to the constraints, which may lead to inferior performance of the algorithm. In this paper, first a concept of biased dominance or b-dominance to bias the search directly and explicitly is introduced, and then by combining b-dominance with a differential evolution, a Biased Multiobjective Optimization (BMO) algorithm is proposed for solving the constrained single-objective optimization problems. The BMO algorithm is comprehensively evaluated on 22 well-known benchmark test functions and the experimental results indicate that the BMO algorithm is capable of achieving competitive results compared with other state-of-the-art methods.

This paper proposes a scheduling strategy based on real-time pricing in smart grids. A hierarchical game is employed to analyze the decision-making process of generators and consumers. We prove the existence and uniqueness of Nash equilibrium and utilize a backward induction method to obtain the generation and consumption strategies. Then, we propose two dynamic algorithms for the generators and consumers to search for the equilibrium in a distributed fashion. Simulation results demonstrate that the proposed scheduling strategy can match supply with demand and shift load away from peak time.

The problem of state and output feedback regularization for descriptor systems by Kalman canonical form is investigated. First we give the Kalman canonical form for the descriptor systems, by which structure, the regularization and the impulsive mode elimination can be conveniently explored. Then necessary and sufficient conditions are given for the closed loop system to be regular and impulse-free by a parameterized state or output feedbacks. Furthermore, a structured output P-D feedback is considered and a necessary and sufficient condition for the closed loop systems to be regular and impulse-free by the structured output P-D feedback control is presented. The main results are given in terms of subsystem parameters by the Kalman canonical form, in which the structure of system matrix is revealed. Finally, an example is provided to illustrate the correctness of the theory.

This paper proposes an improved exemplar-based inpainting using image segmentation, image quilting, and spatial blending to reduce the excessively propagating texture and pathological geometric configurations. A graph-based segmentation is used to generate an initial segmented map. The segmented regions are merged by a K -means approach with texture similarity to generate a further texture-based segmented map, which reduces the candidate source space and determines whether to utilize image quilting in the iterative updating process. An improved spatial blending is introduced as a postprocess to smooth the filled image when the filling process is completed. Experimental results show that this exemplar-based inpainting approach has a good visual effect and reduces the computing time.

A 3—D probe for measuring the diameter and form errors at any particular section for small blind holes or slots with diameter or width down to 0.2 mm and depth to diameter ratio up to 20 was developed. Since optical methods are difficult to use for measuring the diameter of blind hole at any cross section, a method with mechanical stylus was used. The stylus is treated as an elastic element and a theory of elastic transmission was developed. The stylus can be introduced to small holes automatically and the deflection of the measuring stylus is compensated. Experiments show that the accuracy is better than 1μm.

In this paper, the problem of finite time consensus is discussed for multiple non-holonomic mobile agents. The objective is to design a distributed finite time control law such that the controlled multiple non-holonomic mobile agents can reach consensus within any given finite settling time. We propose a novel switching control strategy with the help of time-rescalling technique and graph theory. The numerical simulations are presented to show the effectiveness of the method.

The job-shop scheduling problem (JSP) is a hard combinatorial optimization problem. In this paper, the mixed programming of MATLAB and VC is considered to solve the JSP. Firstly, MATLAB is used to implement an improved genetic algorithm (GA), and then the program is packaged into a dynamic link library (DLL). Secondly, VC is used to realize the input/output interface and call the GA DLL to schedule and store the scheduling results into the ORACLE database. Finally, the simulation results show that the improved GA has good optimization performance in solving JSP and the mixed programming design is effective.

Genetic algorithm is a kind of common method to solve nonlinear programming problems. To improve the computational efficiency of the algorithm, a genetic algorithm based on a new real code (NRCGA) was proposed, which could solve a class of nonlinear programming problems. The new real coded strategy can be used to repair all of the infeasible chromosomes by simply sorting and keeping search within the feasible region. NRCGA is more accurate than the existing methods on equality constraint handling. Many examples show that the new algorithm has high search efficiency and strong robustness.

A new angle measurement system with optical grating is presented in the paper. Its distinguishing features are: (1) Gratings having sine function transmissivity are used as the index gratings. The harmonic errors of the Moire fringes are greatly reduced. (2) Errors caused by zero offsets, inequality in amplitude and nonorthogonality in phase of two Moire fringe signals are corrected by real time software error correction. (3) Four unequally spaced reading heads are used to eliminate the errors caused by the graduation error of optical grating and error motions of the spindle. The experimental device gives an accuracy about 0.2 arcseconds.

In this paper, the chaos synchronization of two coupled Duffing system via active disturbance rejection control is investigated. When the controller is not used, the synchronization will occur only if the coupling coefficient satisfies some condition. But when the condition is not satisfied, the synchronization can not be achieved. We adopt the active disturbance rejection control technique to accomplish the chaos synchronization without needing to consider the value of the coupling coefficient and the control scheme is robust to the total disturbance. The simulation results verify the validity of the proposed control approach.

The flexible manufacturing system (FMS) is a complex discrete event dynamic system (DEDS). The Petri net is suitable for describing the DEDS, so the Petri net is used to model the FMS. Aiming at the scheduling optimization of the FMS, an improved genetic algorithm (GA) is proposed and applied to the scheduling of the Petri net model. An approximate optimal solution is given. Then a given FMS example is designed, modeled and optimized, and the effectiveness and real-time of the proposed model and algorithm are proved through the experiment.

The consensus speed of leader-following multi-agent systems with double-integrator dynamics is considered. Based on the feature of leader-following multi-agent system with fixed undirected topology, an improved algorithm is proposed, which is more effective than the traditional algorithm. The maximum consensus speed (maximum convergence speed) of the improved algorithm is also achieved and it is compared to that of the traditional algorithms. Simulation shows the effectiveness and the correctness of the proposed results.

Summary A new method of roundness and spindle error motion measurement is presented in this paper. Roundness error of the workpiece and radial error motion of the spindle are measured simultaneously by using 4 probes mounted with certain angle arrangement. This method gives high accuracy for all harmonics which is difficult for three point method. Based on error analysis a methodology for selecting optimal parameters is given. Both computer simulation and experiment justify the high accuracy of proposed method.

An optical method is proposed for in-situ measurement of angles of space elements separated at a distance of several or several tens of meters. When it is necessary to measure large objects or geometrical elements within a large scale space, it is not always possible to bring these workpieces to conventional coordinate measuring machines (CMMs) which are widely used in industries. Mobile measuring systems provide ideal solutions for these applications. The basic idea of the presented research work is to set up the multiple common optical references through which the dimensional inspections of separation angles of bifacial lines in a large scale space can be fulfilled. The angles between the projection light and each element can be captured through a machine vision system, and thereafter the angles between those corresponding elements can be determined using the geometrical principles. The method and the calibration approach have been validated on our designed work station.

This paper considers semi-global robust finite time stabilization of non-holonomic chained form systems with perturbed terms. The objective is to design a non-smooth state feedback law such that the controlled chained form system is both Lyapunov stable and finite-time convergent within any given settling time for any given initial states. We propose a novel switching control strategy with help of time-rescaling and Lyapmiov-based method.

This paper is devoted to the problem of H ∞ norm computation for discrete-time symmetric descriptor systems. Firstly, we present new versions of the bounded real lemma for the discrete-time systems and generalized bounded real lemma for the discrete-time descriptor systems. Then, we give the explicit expression to H ∞ norm for discrete-time symmetric more general systems and discrete-time symmetric descriptor systems. The results have obvious computational advantages, especially for large scale symmetric systems. Finally, two numerical examples are given to illustrate the results.

A sliding mode controller is designed for the longitudinal dynamics of a generic hypersonic vehicle. A generic nonlinear longitudinal dynamics model for wedge-shaped vehicle is used. Based on the dynamic inverse control, the sliding mode is adopted with the reaching law that contains a linear-quadratic controller. Optimal control techniques can be applied to search the parameters of linear-quadratic controller. Lyapunov stability analysis is included. Simulations demonstrate that the controller designed has good tracking performance and robustness in the presence of parametric uncertainty.

The differential geometry method is proposed to solve the high-accuracy speed control problem of forging machine. Considering the pipe's effect the model is built as a 6-degree affine nonlinear equation which is equivalent to a linear model through differential geometric feedback linearization. For this equivalent linear model the good performance of speed is gained through a pole assignment method. The simulation shows this method is effective.

A new method for straightness measurement based on distance measurement from two reference points is introduced in this paper. “he distinguishing feature of this method is that it does not require a straightness reference. It gives high accuracy due to high accuracy in displacement measurement. A practical device used for quick distance measurement based on a turnable laser interferometer with two end balls is designed. Accuracy analysis of the instrument is given in detail. Theoretical analysis and experiment show that this method gives high accuracy in straightness and straightness error motion measurements.

The delay-dependent H-infinity guaranteed cost control problem for linear systems with state delay is considered. A delay-dependent condition for the existence of H-infinity guaranteed cost state feedback controller is presented in terms of linear matrix inequality such that the resulting closed-loop system is asymptotically stable and guarantees H-infinity performance index. It can be proved that the condition also satisfies the requirement of guaranteed cost control and an upper bound on the given cost function can be obtained. Furthermore, a design method of the optimal H-infinity-guaranteed cost control law is given against the constant initial value. Finally, numerical examples are provided to demonstrate the effectiveness and feasibility of the proposed results.

The backstepping control is investigated for a class of unknown nonlinear systems in parametric-pure-feedback form. Neural networks(NNs) are applied to approximate the unknown dynamics. The adaptive laws of the weights of NN and the ideal sliding mode are derived in the sense of Lyapunov function, so the stability can be guaranteed. The proposed control not only relaxes the assumptions of nonlinear systems, but also holds the robustness. Moreover, the tracking error can converge to zero asymptotically. Simulations illustrate the effectiveness of the proposed approach.

In this paper, the robust stochastic stabilization problem of uncertain Makovian jumping linear systems subject to actuator saturation is considered. The concept of domain of attraction in mean square sense is used to analyze the closed-loop stability. By using a class of stochastic Lyapunov function, a design procedure for the robust and non-fragile state feedback controller is developed based on the linear matrix inequality approach. Finally, a numerical example is provided to show the effectiveness of the method.

In this paper, we consider the problem of designing H∞ static output feedback controller for systems with delayed state, delayed input and sensor failure. Two sufficient conditions for the existence of H∞ output feedback controllers are presented. Furthermore, by using variable transformation and Schur complement, the obtained result can be rewritten as a matrix inequality representation. Through a set of solution of matrix inequalities, we can obtain the static output controller that can make the closed-loop system asymptotically stable, and its H∞ norm being less than the given bound. Finally, an example is presented to show that the effectiveness of the method.

A smart non—contact optical displacement probe in which Holographic Optical Element(HOE) plays a major role is proposed. A HOE is basically a hologram which is a diffraction element recorded in a thin film. In this paper, the equation of the interference fringe patterns of HOE is derived. the patterns of a CGH master are written by e—beam lithography with a resolution reduced ten times. The HOEs are duplicated as 5mm in diameter. Several technique problems, such as double holo—knife—edge method, aspheric objective lens and nonlinearity correction are discussed. The experimental results are presented.

A method of machine geometry calibration using 1-D ball array is presented. A series of balls are equal spaced fixed on a rigid bar. The spacings between balls are calibrated by a special laser interferometer. The position of the balls are sensed by a magnetic socket or a 3-D noncontact capacitive probe. The distinct feature of the ball array is that it gives 3-D positioning errors of the CMK simultaneously. It can be used for measuring all 21 source eroors and for error compensation of CMM. The straightness errors are measured by using reversal method. The angular error motions are determined by measuring the displacement or straightness errors of two parallel lines. The angular error are determined by using the diagonal lines. The 1-D ball array has low cost, high efficiency and high accuracy. It is expected to find wide applications in machine calibration and error compensation.

In order to improve the measurement accuracy of cylinder shell resonating density meter, the paper presents many means of methods to lower the measurement error from the liquid temperature, pressure, viscidity and gas bubble in the liquid, and designs a novel cylinder shell resonating density meter. Taking typical calibration experiments as example, the paper gives the detailed steps of calculating uncertainty component of the cylinder shell resonating density meter, and values the combined uncertainty. The experiments and analysis show the combined uncertainty is 0.96kg/m3 when the measurement result is 785.16 kg/m3, and the relative uncertainty is 0.12%.

This note deals with the delay-dependent stability and stabilization of linear system with state and input delays. Firstly, for the nominal system, by introducing the augmented Lyapunov functional and some free-weighting matrices, new delay-dependent stability and stabilization criteria of the system are presented. Then, these new conditions are extended to handle norm-bounded uncertain systems with state and input delays, which show less conservativeness. Numerical examples are given to illustrate the effectiveness of the proposed results.

This paper considers the robust guaranteed cost control problem for uncertain linear discrete-time systems subject to actuator saturation. By using the linear matrix inequality (LMI) approach, we obtain sufficient conditions for the existence of a state feedback control law, and the problem of designing the optimal guaranteed cost controller is converted to a convex optimization problem with LMI constraints. Numerical examples are given to illustrate the effectiveness of the proposed results.

The purpose of this paper is to design robust guidance laws of the missile to the maneuvering target based on guaranteed cost (GC) control. The robust stabilizing GC controller is designed in terms of linear matrix inequalities (LMIs), and the optimal guaranteed cost (OGC) controller is given. Simulations are implemented by digital control in several cases of maneuvering targets and launching sites, and then performances of proportional navigation (PN), GC and OGC are compared. Simulation results show the effectiveness of the proposed guidance laws.

In this paper, we consider the problems of robust stability and stabilization of Lurpsilae control systems with time-varying delay. Firstly, by making use of an integral inequality, some delay-dependent robust stability conditions of the system are presented. Then, a sufficient stabilization criterion is established in the terms of linear matrix inequality (LMI), based on the above stability condition and matrix decomposition technique. Finally, numerical examples are given to illustrate the effectiveness of the proposed results.

The delay-dependent H-infinity control problem for linear descriptor systems with state delay is considered. A delay-dependent condition for the existence of H-infinity memorial state feedback controller is presented in terms of matrix inequality such that the resulting closed-loop system is asymptotically stable and guarantees H-infinity performance index, and this condition fits the general descriptor system with time-delay whether it is impulse-free or not. The upper bounding on the weighted cross products, which often leads to conservatism, is not required for obtained delay-dependent results. Finally, numerical examples are provided to demonstrate the reduced conservatism and effectiveness of the proposed results.

The problem of uncertain homing missile guidance is considered. The guidance control is designed with the state feedback of guaranteed cost control. On the basis of LMI, the robust stabilizing controller is presented, and a guidance algorithm is given which can successfully guide the missile to the target. Meanwhile, the upper bound of system performance is given. For a portable homing missile, the ideal trajectories are protracted. Simulations show the algorithm can successfully guide the missile to head-on or tail-on the maneuver target. Furthermore, for the same target, comparisons are carried out in the case of the different missile launching site. It is illustrated that the designed guidance algorithm is not only robust to disturbance but also small normal overload especially on the encountering time.

This paper deals with the stability analysis and controller design of linear systems with state delay and input saturation. First, a delay-dependent stability criterion is derived within the framework of linear matrix inequalities by using some free matrices to express the relationship of the terms in the Leibniz-Newton formula. Then the problem of designing linear state feedback laws which guarantees the stability of the closed-loop system and enlarging the domain of attraction is formulated and solved as an optimization problem with LMI constraints. A numerical example is used to demonstrate the effectiveness of the proposed design technique comparing with the previous results.

This paper is devoted to the absolute stability analysis of Lurie systems with time delay. A new delay-dependent Lyapunov function analyzing approach is proposed to reduce the conservativeness in computing the upper bound of the maximum allowed delay. Some new stability conditions are developed in terms of linear matrix inequalities. Examples are provided to demonstrate the reduced conservatism of the proposed methods.

This paper deals with the problem of local stabilization for linear time-delay systems subject to actuator saturation. Different from the traditional Lyapunov-Krasovskii approach to estimate the domain of attraction, a less conservative method based on Lyapunov-Razumikhin approach is presented using linear matrix inequalities technique. The effectiveness of the proposed method is illustrated with an example.

This paper investigates the issue of adaptive finite-time control for hyperchaotic Lorenz–Stenflo systems with parameter uncertainties. Based on finite-time Lyapunov theory, a class of non-smooth adaptive finite time controllers is given to guarantee the adaptive finite-time stability and make the states of the systems converge to the origins within a finite-time. Finally, illustrative examples are presented to verify the effectiveness of the proposed adaptive finite-time controller.