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In geometric constraint solving, the constraints are represented with an equation system F(U, X) = 0, where X denotes the unknowns and U denotes a set of parameters. The target solution for X is noted XT. A witness is a couple (UW, XW) such that F(UW, XW) = 0. The witness is not the target solution, but they share the same combinatorial features, even when the witness and the target lie on two distinct...
The problem of robust stabilization is considered for a class of nonlinear systems in the presence of uncertain system parameters, external disturbances, and unknown time-varying virtual control coefficients. It is supposed that the upper bounds of external disturbances, and the upper and lower bounds of unknown time-varying virtual control coefficients are unknown. Some improved adaptation laws with...
In this paper, a new definition of a Lα operator is introduced for considering the right coprime factorization theory to stabilize the nonlinear system. First, some basic knowledge about nonlinear operators are reviewed. Second, the new definition of the Lα operator is introduced, and then based on the Lα operator, some theorems are derived. And considering the right coprime factorization, the new...
Network based recommendation systems leverage the topology of the underlying graph and the current user context to rank objects in the database. Random-walk based techniques, such as PageRank, encode the structure of the graph in the form of a transition matrix of a stochastic process from which the significances of the nodes in the graph are inferred. Personalized PageRank (PPR) techniques complement...
This paper presents two new design methods for self-repairing control systems (SRCSs) based on nonlinear high-gain feedback. The SRCS can replace the failed sensor with the back-up. For self-repairing against sensor failures, the nonlinear detection filter is utilized, that has a finite escape time if the sensor fails. Monitoring the diverging signal from the detection filter makes it possible to...
Local oriented statistical information booster (LOSIB) is a descriptor enhancer based on the extraction of the gray level differences along several orientations. Specifically, the mean of the differences along particular orientations is considered. In this paper we have carried out some experiments using several classical texture descriptors to show that classification results are better when they...
Computing descriptors for image features is a crucial task in many applications. A good feature descriptor is capable of providing invariance to geometric and lightning transformations while consuming as few memory as possible. Recently, there were proposed new approaches to compute a feature descriptor that rely on pixel intensity comparisons in order to generate a binary string, generating binary...
Scene acquisition using RGB and Near Infra-Red (NIR) filters generates useful visual information about scene contents. But it induces significant intensity and textural changes between RGB and NIR images of the same scene. It becomes a challenging problem to perform interest point based image matching under such intensity and textural changes. To cope with this problem, a novel method for the description...
Recently, spectral manifold learning algorithms on pattern recognition and machine learning orientation have found wide applications. The common strategy for these algorithms, e.g., Locally Linear Embedding (LLE), facilitates neighborhood relationships which can be constructed by knn or ∊ criterion. This paper presents a simple technique for constructing the nearest neighborhood by combining ℓ2 and...
In this paper we investigate the problem of embedding a number of points given certain (but typically not all) inter-pair distance measurements. This problem is relevant for multi-dimensional scaling problems with missing data, and is applicable within anchor-free sensor network node calibration and anchor-free node localization using radio or sound TOA measurements. There are also applications within...
The Max-Tree is an efficient data structure that represents all connected components resulting from all possible image upper threshold values. Usually, most of its nodes represent irrelevant extrem a, i.e. noise, or small variations of a connected component. This paper proposes the Maximal Max-Tree Simplification (MMS) filter with a normalized threshold criterion (MMS-T) and a Maximally Stable Extremal...
A novel affine registration technique is proposed which efficiently handles the partial occlusion problem. The proposed method is working without point wise correspondences or radiometric information's. The aligning transformation is found by solving a system of non-linear equations and minimizing the area of occlusions. Each equation is generated by integrating a non-linear function over the foreground...
We compare the objective functions used by GR2T [1] and the L2E estimator [2] that have both been proposed for robust parameter estimation. We show their similarity when estimating location parameters. Of particular interest is their ability for dealing with the scale parameter that is often unknown and acts as a nuisance parameter. Both techniques are tested experimentally for regression (e.g. to...
This paper presents the structure of model reference adaptive control based on fuzzy basis function. Initially, the techniques of fuzzy basis function are introduced to approach uncertain (or unknown) nonlinear systems. In addition, a heuristic adaptive algorithm, which is robust feature under the Lyapunov stability criterion is developed so that the output of the plant tracks a reference model output...
Differential uncertainty is involved in actual system inevitably. That brings great inconvenience for the controller design. In this paper we treat the differential uncertainty as a separate item, and use the robust control theory to analyze the robust performance. Considering the impact of parameter variations, un-model dynamics and external disturbances, we design robust H2/H8 controller. We use...
An auto-landing guidance law on the basis of sliding mode control (SMC) is presented in this paper for landing an unpowered reusable launch vehicle (URLV) at the predetermined landing site. The guidance scheme, which takes the full nonlinear point-mass dynamics into account, is developed in three-dimensional space. For the sake of dealing with large initial condition errors, the guidance process is...
This paper focuses on an internal model tracking control problem of an uncertain impulsive switched system. The contribution of this study is to develop an internal model tracking control law integrated with the guaranteed cost control algorithm for uncertain impulsive switched systems. Firstly, an uncertain impulsive switched system with guaranteed cost control is stated and some important theorems...
Dynamic stability analysis is one of important issue in electrical power system study. This paper aims to analyze and design the control of power generation operation system in small disturbance events. This condition is affected by changes in the prime mover of mechanical power input in generator system due to power fluctuation in load, so that the system becomes unstable. In the analysis of electrical...
The paper presents a new robust adaptive augmented backstepping control scheme for rapid turning maneuver of a high agility unmanned aerial vehicle (UAV). The proposed control scheme consists of a baseline backstepping controller which can deal with the couplings of kinematic and inertial during fast rolling and generates commands tracking control inputs, and a robust adaptive compensator which can...
This paper puts forward a four-axis dual rotor unmanned aerial vehicle (UAV) and builds the mathematical model. For this model, an aircraft trajectory control method based on robust compensation is presented. To reduce the effects of external disturbances and model parameters' uncertainty, the robust compensator is added to the classical PD control. Simulation results demonstrate that this method...
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