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This paper focuses on the problem of synchronization stability analysis for complex dynamical networks with coupling delays, both continuous and discrete cases are considered. With the method of delay partitioning, less conservative criteria are derived in the form of linear matrix inequalities (LMIs). Numerical examples are provided to show the effectiveness of the proposed results.
The steam and water system of boiler is always divided into a drum level control system and a main steam temperature control system independently. The coupling is existed actually between these two loops, but it is often ignored by engineer or system designer. In this paper, the coupling between the drum level control system and the main steam temperature control system is determined by the controlled...
This paper discusses the problem of finite frequency positive real control for singularly perturbed systems based on GKYP lemma. The purpose of this study is to design a state feedback controller such that the resulting closed-loop system is stable, and achieves the extended strictly positive realness for singularly perturbed systems at low and high frequencies. By employing GKYP lemma, respectively,...
In the converter steelmaking vaporized cooling process, the serious ldquofalse water levelrdquo phenomenon appears at the drum water level of waste heat recovery boiler as the gas is burnt completely. According to the energy conversation law, a steam flow feed-forward compensator is designed as the open-loop controller to improve the previous control system. It is used to overcome the great nonlinearity...
A real-time simulation approach with rapid prototyping for digital electronic engine control (DEEC) is proposed, and an ECU-in-the-loop real-time simulation platform with this approach is developed. The software-hardware framework of this platform is mainly composed of MATLAB/RTW for rapid prototyping from aero-engine modeling to embedded implementation, VxWorks real-time operating system (RTOS) for...
The differential J2 influence is a big challenge to design periodic relative motion between two spacecrafts on neighboring eccentric orbits. A linearized time-variant equation is presented to describe the formation dynamics in the presence of J2 disturbances. For five kinds of basic formation configurations, numerical simulations show that the spacecrafts will not separate over time, when the initial...
Having analyzed the drawbacks of image retrieval methods based on content, a novel image retrieval algorithm based on spacial color distribution entropy is proposed in this paper. Firstly, an image is segmented several regions by this algorithm. Secondly, spacial color distribution entropy is designed for each region, which takes not only the local color feature of the region into consideration, but...
Modal analysis of satellite system is the basic requirement for the satellite structural design. The theory of normal modes is analysed rounded in this paper. And the finite element model of a small satellite, of which the monolithic structure is honeycomb sandwich plate, is established by using the finite element analysis software PATRAN/NASTRAN. Furthermore, the equivalent model for honeycomb sandwich...
The linear time-invariant systems of equivalent one another in algebra represent mathematical models of a same physical system described in different state vectors. Algebra equivalent observer (AEO) is derived from the non singularity of state space presentation in linear system, which is a very important concept in control theory. For the rapid calculation of parameters of AEO, which have effect...
An integrated flight control system is designed according to the six DOF nonlinear model of pitching channel of hypersonic vehicle X-43A. The system is composed of one fuzzy controller and two PD controllers. Based on genetic algorithm, the optimization process of fuzzy control rules and PD feedback parameters is carried out automatically without expertspsila knowledge and training data in advance...
Aiming at the rapidity control problem of direct drive electro-hydraulic (DDEH) servo rocket rudder, a design method of adaptive fuzzy sliding mode control with friction torque dynamic compensation is presented. The friction torque dynamic compensation method is introduced to enhance the response of the system. The adaptive fuzzy controller is introduced to solve the problem of the uncertain parameter...
Using the advantage of polynomial spline interpolation to represent spatial curves with good approximation effect and mature technology, an instruction format with polynomial spline curves, which is suitability for five axes coordinated real-time interpolation, is presented against the current five axes coordinated linear interpolation method with drawbacks of low-speed, low-accuracy and great NC...
Collaborative filtering is the process of predicting how a user would rate a given item from other user ratings. we propose a new collaborative filtering algorithms, ratio-based collaborative filtering algorithms, by calculating the ratio between the ratings of one item and another for users who rated both to predict the ratings. Ratio-based collaborative filtering algorithms are easy to implement,...
In this paper we propose a novel variational formulation for arbitrary surface reconstruction from 3D scattered points. An implicit surface is adopted for its more advantages, such as continuity and differentiability, easy estimation of points inside or outside the shape, and convenient implementation for these complicated set operations. The presented new energy functional in this paper considers...
Geomagnetic field is one of the geophysical fields of the Earth and can be used to limit the error accumulation of the inertial navigation system (INS). A geomagnetic aided navigation system is proposed in the paper. Two alternate processes are designed in the system - the match and the filter. In the former part, a contour constraint based correlation method is used to eliminate the initial position...
This paper presents the lateral/directional stability and control analysis and the control design results for the Reusable Launch Vehicle on suborbital reentry. The relative location of the open-loop quadratic poles and zeros is discussed. The feedback of roll rate to aileron is of better effectiveness to damping the Dutch roll than the feedback of yaw rate. To avoid the adverse yaw by ailerons, a...
A modular, configurable, interoperable, scalable configuration computer numerical control (CCNC) system is built and implemented that provided a way for rapid customization and development of a new CNC system by combining the advantages from the technology of component. After analyzing the key technologies of the CCNC system, such as object-oriented, component and modularization, the conception of...
Oscillators with bounded delayed input are stabilized by a sliding mode control law. In the control law, sign function is replaced by high gain function to avoid chattering in the presence of time delay. A condition is developed to determine the gain. Simulation is conducted to show the effectiveness of the theoretical analysis.
GPS (Global Positioning System) have high position and velocity precision, star sensor is a high accuracy attitude measurement system, SINS (Strapdown Inertial Navigation System) can get all navigation information precisely at short period. In order to realize high-precision navigation, according to analyze the error model of above systems, both of the state equations and measurement equations were...
Piezoelectric materials are finding increasing applications in active vibration control of structures. A widely used modeling technique for piezoelectric flexible structures is the assumed modes method which results in an infinite dimensional model of the composite structure. The paper builds the model of piezoelectric flexible structures and calculates the modal frequency by the application of ANSYS...
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