This paper proposes a real-time distributed algorithm for a team of smart cameras to self-organize and perform video surveillance of an open boundary. In particular, our algorithm simultaneously partitions the boundar...
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Robust asymptotic stability for hybrid systems is considered. For this purpose, a generalized solution concept is developed. The first step is to characterize a hybrid time domain that permits an efficient description...
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Robust asymptotic stability for hybrid systems is considered. For this purpose, a generalized solution concept is developed. The first step is to characterize a hybrid time domain that permits an efficient description of the convergence of a sequence of solutions. Graph convergence is used. Then a generalized solution definition is given that leads to continuity with respect to initial conditions and perturbations of the system data. This property enables new results on necessary conditions for asymptotic stability in hybrid systems.
An important index to evaluate the process efficiency of coal preparation is the mineral liberation degree of pulverized coal,which is greatly influenced by the particle size and shape distribution acquired by image *...
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An important index to evaluate the process efficiency of coal preparation is the mineral liberation degree of pulverized coal,which is greatly influenced by the particle size and shape distribution acquired by image ***,the agglomeration effect of fine powders and the edge effect of granular images caused by scanning electron microscopy greatly affect the precision of particle image *** this study,we propose a novel image segmentation method derived from mask regional convolutional neural network based on deep learning for recognizing fine coal ***,an atrous convolution is introduced into our network to learn the image feature of multi-sized powders,which can reduce the missing segmentation of small-sized agglomerated ***,a new mask loss function combing focal loss and dice coefficient is used to overcome the false segmentation caused by the edge *** final comparative experimental results show that our method achieves the best results of 94.43%and 91.44%on AP50 and AP75 respectively among the comparison *** addition,in order to provide an effective method for particle size analysis of coal particles,we study the particle size distribution of coal powders based on the proposed image segmentation method and obtain a good curve relationship between cumulative mass fraction and particle size.
Hybrid systems with memory are dynamical systems exhibiting both hybrid and delay phenomena. We present a general modelling framework for such systems using hybrid functional inclusions, whose generalized solutions ar...
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We show that the robustification method of Krstic et al. (1996) for nonlinear systems with linear input unmodeled dynamics guarantees global boundedness of closed loop solutions when the unmodeled dynamics subsystem i...
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We show that the robustification method of Krstic et al. (1996) for nonlinear systems with linear input unmodeled dynamics guarantees global boundedness of closed loop solutions when the unmodeled dynamics subsystem is relative degree zero and minimum phase. We also prove that the solutions can be made to converge to an arbitrarily small ball around the origin.
Analyzes the robustness of a nonlinear observer design introduced previously by the authors. For uncertainties in the nonlinearities, bounds are given within which the observer error gradually increases with an increa...
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ISBN:
(纸本)0780366387
Analyzes the robustness of a nonlinear observer design introduced previously by the authors. For uncertainties in the nonlinearities, bounds are given within which the observer error gradually increases with an increase in the uncertainty. For dynamic modeling errors, a robust output-feedback design is developed using ISS small-gain tools. A jet engine compressor example is used to illustrate the design.
We consider the problem of steering an autonomous vehicle to locate a radiation source utilizing measurements of the radiation intensity only. We propose a control algorithm that locates the source through a sequence ...
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We consider the problem of steering an autonomous vehicle to locate a radiation source utilizing measurements of the radiation intensity only. We propose a control algorithm that locates the source through a sequence of line minimizations of the radiation intensity. We implement in a hybrid controller, with sample-and-hold and logic variables, a discretized version of the algorithm suitable for steering a point-mass vehicle. The algorithm confers global convergence and practical stability properties to the closed-loop hybrid system. We discuss these properties and characterize the region of convergence for the vehicle. Convergence and stability results are supplemented with simulations.
Auto-regulatory transcriptional feedback, where the protein expressed from a gene inhibits its own transcription, is known to reduce stochastic fluctuations in protein numbers. Recent work has demonstrated the existen...
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ISBN:
(纸本)9781424445233
Auto-regulatory transcriptional feedback, where the protein expressed from a gene inhibits its own transcription, is known to reduce stochastic fluctuations in protein numbers. Recent work has demonstrated the existence of negative feedback loops not only at the transcriptional level but also at the translational level. We investigate the noise suppression abilities of feedback loops at the translational level and compare them with transcriptional feedback. In particular, we consider two feedbacks at the translational level: translation blocking feedback, where the protein inhibits the translation of its mRNA, and degradation enhancing feedback, where the protein increases the degradation rate of its mRNA. We derive analytical formulas for the protein noise level corresponding to different feedback mechanisms. These noise levels are then compared with each other for fixed steady-state average number of protein and mRNA molecules. We show that translation blocking feedback always yields smaller levels of protein noise than transcriptional feedback. We further show that the difference between the protein noise levels with translation blocking and transcriptional feedback critically depends on how fast the protein dynamics is compared to the mRNA dynamics. In particular, this difference increases as we make the protein dynamics faster than the mRNA dynamics, while making it slower has an opposite effect. Finally, we show that degradation enhancing feedback provides the same noise level as transcriptional feedback. This result shows that regulation at the translational level may not always be better than regulation at the transcriptional level in terms of reducing noise in the protein population.
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