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This paper presents a method to detect small flooded areas from images which contain also vegetation zones. So, two classes are considered: flood class and vegetation. For the learning phase a supervised technique based on small patches is used. Based on efficiency analysis, the Histograms of Oriented Gradients on H colour channel and mean intensity on gray level are selected as discriminated features...
In this paper, an adaptive adjustment method for the kernel parameter used in the kernel adaptive filters (KAFs) is proposed. The KAF is one of the linear-in-the-parameters (LIP) nonlinear filters, and is based on the kernel method used in machine learning. Typically, the Gaussian kernel function is used, but there is no effective method for automatically adjusting its parameter that influences the...
Social network analysis can be used to investigate collaboration in learning networks, which can be modeled as social graphs. We have already proposed a conceptual framework for knowledge extraction and visualization from a social media-based learning environment, starting from specific educational needs identified by the instructors. In the current paper, we experimentally validate this framework...
Over the past years, the worldwide population, especially in developed countries, faces a new issue: the ageing of the population. In developed countries, special attention is paid to monitoring and providing medical services to the elderly. In EU, the number of persons dealing with cardiovascular diseases is increasing. The number of persons needing special medical services depends on the economic...
The 2-dimensional bin packing problem appears in various fields across many industries such as wood, glass, or paper industries. They may differ in terms of specific constraints with respects to each area but they all share a common objective that is to maximize the material utilization. Belonging to the class of NP-Hard problems, there exist no efficient method to solve it, but only approximate solution...
The reports from last years outline the fact that the web crawlers (robots, bots) activities generate more than a half of web traffic on Internet. Web robots can be good (used for example by search engines) or bad (for bypassing security solutions, scraping, spamming or hacking), but usually all take up the internet bandwidth and can cause damage to businesses that rely on web traffic or content....
One of interesting problems, arising with deployment of large-scale systems, is integration of its nodes (systems / devices). In this work, we discus how to apply semantic technologies, as a mechanism to support node integration and facilitate interoperability within the developed ecosystem. We focus on pragmatic aspects of the proposed solution, discussed from the perspective of the Dependable Embedded...
Two wheel balancing robot referred as inverted pendulum is analyzed and implemented using Lego Mindstorms kit. The mathematical model was derived based on inverted pendulum equations with real parameters values appropriate to the real robot. The linearized state space mathematical model was converted into δ-domain counterpart due to the advantages of discrete time δ-operator in the context of finite...
A significant raise in the use of illicit psychoactive substances has been reported in the last decade. This trend is probably due, especially in the case of amphetamine-type stimulants (ATS), to the fact that they are the easily synthesized. Globalization offers new ways of procuring the precursors of these substances (e.g. online) and helps cover the increasing production needs of clandestine laboratories...
This paper presents a method to improve the conservative (shape-independent) controllers from guaranteed-cost LMIs using Q-learning policy iteration setups which learn optimal controllers from data. In this context, the proposed approach uses an initial parametrization based on the LMI solution and the learning process includes parameters related to the nonlinearity of the system (and its gradient)...
A quasi-optimal regulator design problem is solved for nonlinear control objects described in the state-space by nonlinear matrix ordinary differential equations with quadratically-cubic nonlinearities, where polynomial terms are constructed using the Kronecker matrix product. A.A. Krasovskiy's generalized work criterion is used as the cost functional. The Lyapunov function is determined by the integration...
The purpose of this study is to design a LQR controller for the SEPIC (Single-Ended Primary-Inductor Converter) converter which is widely employed in industrial DC-DC power conversion and is also starting to see widespread use in PV applications. Circuit-Averaging-Method is used to acquire the mathematical model of the given system. Controllers are designed based on the Small-Signal model. LQR and...
State space model of descriptor continuous-time linear system with different fractional orders is addressed. Necessary and sufficient conditions for positivity of the descriptor continuous-time linear system with different fractional orders are formulated. Decentralized controller for stabilization of the class of positive descriptor fractional systems is given. Method for finding gain matrix of the...
Optimization of anti-windup controller design is achieved for non-linear systems with actuator saturation. The systems are represented as Euler-Lagrange systems, and the proportional and integral (PI) controller, in which the gravity term is cancelled by a non-linear compensation technique, is used. The goal of optimization is to minimize the saturated input, i.e., the difference between the control...
We propose herein a data-driven dead-zone (DZ) compensation strategy using a model-free Virtual Reference Feedback Tuning (VRFT) approach. The VRFT tuning scheme is accommodated for two controller structures: the first one which explicitly includes a model of the DZ inverse to be identified and the second one which uses a Neural Network (NN) to model the controller to be identified. The main question...
This paper presents a vibration control design to the string-tip-mass system by using a non-symmetric peak-detector mechanism. Previously, this peak-detector system was used as an easy algorithm to mitigate vibration on a real flexible structure. Moreover, its mathematical representation is simple and it just has two parameters to tune. Following this former experience, we adequate this strategy to...
The paper provides new results for testing the flow-invariance of time-dependent sets with arbitrary shapes, with respect to trajectories of continuous-time nonlinear systems. The approach represents a generalization of a criterion used in the qualitative analysis of ordinary differential equations with solutions in closed sets with hyper-rectangular form. Given a nonlinear dynamical system for investigation,...
Inverted pendulum is one of the fundamental benchmarks in application areas of control engineering and robotics. It is a good example of single input multi output (SIMO) systems. In this paper, identification of a cart inverted pendulum system is carried out and real time control of the system is accomplished by using the PI-PD controller. PI-PD controller is a good approach to control integrating...
This paper defines an optimal quadratic cost bound as a performance index for linear time varying systems subject to a finite time stability constraint. In particular, a sufficient condition for achieving such a guaranteed cost bound satisfying simultaneously the finite time stable constraint is given in terms of differential linear matrix inequalities. This condition is then exploited for the design...
This work faces the problem of frequency deviation in microgrid systems. The considered microgrid includes renewable energy sources such as wind and solar photovoltaic. As long as these sources provide an irregular power supply or there is a sudden change in the system load, the power system frequency deviates. In order to compensate such deviations, alternative, conventional energy sources should...
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