Search results for " and Control"
showing 10 items of 385 documents
Finite Alphabet Control of Logistic Networks with Discrete Uncertainty
2014
We consider logistic networks in which the control and disturbance inputs take values in finite sets. We derive a necessary and sufficient condition for the existence of robustly control invariant (hyperbox) sets. We show that a stronger version of this condition is sufficient to guarantee robust global attractivity, and we construct a counterexample demonstrating that it is not necessary. Being constructive, our proofs of sufficiency allow us to extract the corresponding robust control laws and to establish the invariance of certain sets. Finally, we highlight parallels between our results and existing results in the literature, and we conclude our study with two simple illustrative exampl…
Reminiscence and dementia: a therapeutic intervention.
2015
ABSTRACTBackground:Dementia is a significant public health problem. One non-pharmacological therapy that has shown its effectiveness is reminiscence, which is a psychological intervention designed to address issues of particular relevance to older adults. The aim of this study was to examine the benefits of an integrative reminiscence program in elderly people with dementia.Methods:A quasi-experimental design and purposeful sampling were conducted at two retirement homes. Forty-two elderly adults with dementia were studied to measure the effect of the therapy (23 in the experimental group and 19 in the control group). The treatment group activity was held in 10 sessions.Results:The treatmen…
Global Linear Stability Analysis of the Flow Around a Superhydrophobic Circular Cylinder
2016
International audience; Over the last few years, superhydrophobic (SH) surfaces have been receiving an increasing attention in many scientific areas by virtue of their ability to enhance flow slip past solid walls and reduce the skin-friction drag. In the present study, a global linear-stability analysis is employed to investigate the influence of the SH-induced slip velocity on the primary instability of the 2D flow past a circular cylinder. The flow regions playing the role of 'wavemaker' are identified by considering the structural sensitivity of the unstable mode, thus highlighting the effect of slip on the global instability of the considered flow. In addition, a sensitivity analysis t…
Lead-Lag-Shaped Interactive Force Estimation by Equivalent Output Injection of Sliding-Mode
2020
Estimation of interactive forces, which are mostly unavailable for direct measurement on the interface between a system and its environment, is an essential task in various motion control applications. This paper proposes an interactive force estimation method, based on the well-known equivalent output injection of the second-order sliding mode. The equivalent output injection is used to obtain a frequency-unshaped quantity that appears as a matched external disturbance and encompasses the interactive forces. Afterwards, a universal lead-lag shaper, depending on dynamics of the motion control system coupled with its environment, is used to extract an interactive force quantity. Once identif…
Reference tracking control of hypersonic vehicles using switched linear parameter-varying approach
2013
This paper is concerned with the control problem of the air-breathing hypersonic vehicle using switched linear parameter-varying (LPV) systems approach. By linearizing the nonlinear model of the hypersonic vehicle at trim points and dividing the velocity scope into several partitions, a switched LPV model for the underlying systems is derived. With aid of multiple Lyapunov-like functions technique, the controllers ensuring the tracking of given commands of the closed-loop system are designed under the mode-independent and mode-dependent switching logics, respectively. Simulation results for the hypersonic vehicle show the effectiveness of the proposed method and the advantages of the mode-d…
Model Identification of a Network as Compressing Sensing
2013
In many applications, it is important to derive information about the topology and the internal connections of dynamical systems interacting together. Examples can be found in fields as diverse as Economics, Neuroscience and Biochemistry. The paper deals with the problem of deriving a descriptive model of a network, collecting the node outputs as time series with no use of a priori insight on the topology, and unveiling an unknown structure as the estimate of a "sparse Wiener filter". A geometric interpretation of the problem in a pre-Hilbert space for wide-sense stochastic processes is provided. We cast the problem as the optimization of a cost function where a set of parameters are used t…
Transmission Heterogeneity and Control Strategies for Infectious Disease Emergence
2007
Background The control of emergence and spread of infectious diseases depends critically on the details of the genetic makeup of pathogens and hosts, their immunological, behavioral and ecological traits, and the pattern of temporal and spatial contacts among the age/stage-classes of susceptible and infectious host individuals. Methods and Findings We show that failing to acknowledge the existence of heterogeneities in the transmission rate among age/stage-classes can make traditional eradication and control strategies ineffective, and in some cases, policies aimed at controlling pathogen emergence can even increase disease incidence in the host. When control strategies target for reduction…
Phylogeography and genetic variation of Triatoma dimidiata, the main Chagas disease vector in Central America, and its position within the genus Tria…
2008
Background Among Chagas disease triatomine vectors, the largest genus, Triatoma, includes species of high public health interest. Triatoma dimidiata, the main vector throughout Central America and up to Ecuador, presents extensive phenotypic, genotypic, and behavioral diversity in sylvatic, peridomestic and domestic habitats, and non-domiciliated populations acting as reinfestation sources. DNA sequence analyses, phylogenetic reconstruction methods, and genetic variation approaches are combined to investigate the haplotype profiling, genetic polymorphism, phylogeography, and evolutionary trends of T. dimidiata and its closest relatives within Triatoma. This is the largest interpopulational …
Effects of gender and the representations about the importance of parenthood in the emotional adjustment in couples undergoing assisted reproductive …
2021
Infertility is defined as “the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse” [1]. The emotional adjustment of couples undergoing ART has been widely studied, evidencing the experience of infertility and its treatment have negative effects on the psychological well-being in many cases [2,3]. However, few studies were dedicated to study the role of the intrapersonal attributes of adjustment to infertility, such as attitudes toward parenthood, among this population. Therefore, this study aimed to explore the relationship between emotional adjustment and representations about the importance of parenthood (rejection of childfree lifest…
Bericht des permanenten Sanitäts-Comité der Stadt Riga über seine Wirksamkeit im Jahre 1878
1879
Inhalt: Einleitung ; I. Die Maßnahmen gegen drohende Epidemien ; II. Die Verunreinigungen der Straßen, Höfe, Plätze etc. ; III. Die fließenden und stagnirenden Gewässer ; IV. Die Latrinen und deren Vereinigung ; V. Die Fabriken und gewerblichen Anlagen ; VI. Das Leichen- und Beerdigungswesen ; VII. Die Bibliothek ; BEILAGE : 1. Bericht über den Stadtkanal / Dr. E. Bochmann, F. Weber, H. Malcher ; 3. Untersuchungsresultate der dem Stadtkanal entnommenen Schlammproblem ; 2. Bericht über die W. Franz'sche Knochenküche / Dr. J. Stavenhagen, Berichterstatter, Dr. Gehewe, F. Weber.