Search results for " Stab"
showing 10 items of 1773 documents
New delay-dependent stability of Markovian jump neutral stochastic systems with general unknown transition rates
2015
This paper investigates the delay-dependent stability problem for neutral Markovian jump systems with generally unknown transition rates GUTRs. In this neutral GUTR model, each transition rate is completely unknown or only its estimate value is known. Based on the study of expectations of the stochastic cross-terms containing the integral, a new stability criterion is derived in terms of linear matrix inequalities. In the mathematical derivation process, bounding stochastic cross-terms, model transformation and free-weighting matrix are not employed for less conservatism. Finally, an example is provided to demonstrate the effectiveness of the proposed results.
A Hybrid Control Strategy for Quadratic Boost Converters with Inductor Currents Estimation
2020
International audience; This paper deals with a control strategy for a DC-DC quadratic boost converter. In particular, a hybrid control scheme is proposed to encompass a control law and an observer for the estimation of the system states, based only on the measurements of the input and output voltages. Differently from classical control methods, where the controller is designed from a small-signal model, here the real model of the system is examined without considering the average values of the discrete variables. Using hybrid dynamical system theory, asymptotic stability of a neighborhood of the equilibrium point is established, ensuring practical stability of the origin, which contains es…
Dissipativity-Based Small-Gain Theorems for Stochastic Network Systems
2016
In this paper, some small-gain theorems are proposed for stochastic network systems which describe large-scale systems with interconnections, uncertainties and random disturbances. By the aid of conditional dissipativity and showing times of stochastic interval, small-gain conditions proposed for the deterministic case are extended to the stochastic case. When some design parameters are tunable in practice, we invaginate a simpler method to verify small-gain condition by selecting one subsystem as a monitor. Compared with the existing results, the existence-and-uniqueness of solution and ultimate uniform boundedness of input are removed from requirements of input-to-state stability and smal…
Modelling Rainfall-induced Shallow Landslides at Different Scales Using SLIP - Part II
2016
Abstract This paper (Part II) is companion of another one published in this Conference (Part I). Both the papers describe the approach followed in the application of the SLIP model at different scales to foresee the triggering mechanism of rainfall-induced shallow landslides. In particular, this paper (Part II) focuses on the modeling at medium and large scale (regional and national level). The possibility of using the same means to model the phenomenon from the scale of the representative elementary volume (i.e. flume laboratory tests) to the medium and large scale (hundreds or thousands square kilometers wide areas) allowed from the one hand to strengthen the model assumptions and on the …
A risk assessment proposal for underground cavities in Hard Soils-Soft Rocks
2018
Abstract Underground calcarenite quarries in Marsala (Sicily) have been involved in a number of collapses that have, seriously damaged numerous buildings. The stability conditions were therefore examined in order to assess risk conditions within the historical centre of the town and the surrounding areas, which are subject to urban expansion. Starting with an extensive collection of historical information, the research was carried out through surveys of the cavities, systematic sampling of material, petrographic analysis and geotechnical testing. The results of laboratory tests and in situ investigations provided a geotechnical characterization of both the intact material and the rock mass.…
A time-varying observer for linear systems with asynchronous discrete-time measurements
2017
International audience; In this paper we propose a time-varying observer for a linear continuous-time plant with asynchronous discrete-time measurements. The proposed observer is contextualized in the hybrid systems framework providing an elegant setting for the proposed solution. In particular some theoretical tools are provided, in terms of LMIs, certifying asymptotic stability of a certain compact set where the estimation error is zero. Moreover the case of asynchronous measurements is considered, i.e. when the measurements are not provided in well defined time instants, but they occur at an arbitrary time in a certain time interval. A design procedure based on the numerical solution of …
Trifluoroethanol modulates α-synuclein amyloid-like aggregate formation, stability and dissolution
2016
The conversion of proteins into amyloid fibrils and other amyloid-like aggregates is closely connected to the onset of a series of age-related pathologies. Upon changes in environmental conditions, amyloid-like aggregates may also undergo disassembly into oligomeric aggregates, the latter being recognized as key effectors in toxicity. This indicates new possible routes for in vivo accumulation of toxic species. In the light of the recognized implication of α-Synuclein (αSN) in Parkinson's disease, we present an experimental study on supramolecular assembly of αSN with a focus on stability and disassembly paths of such supramolecular aggregate species. Using spectroscopic techniques, two-pho…
Guava: phytochemical composition of a potential source of antioxidants for cosmetic and/or dermatological applications
2017
Made available in DSpace on 2018-11-28T14:21:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01. Added 1 bitstream(s) on 2019-10-09T18:26:25Z : No. of bitstreams: 1 S1984-82502017000200612.pdf: 803011 bytes, checksum: 199524e8d40cccb25490594ec61b3ed8 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) PADC-FCF-UNESP Fundação para o Desenvolvimento da UNESP (FUNDUNESP) Guava (Psidium guajava L.) is a native fruit of the American tropics with commercial applications for its taste, flavor and aroma. Numerous pharmacological uses have been described for it, such as the antiseptic effect of it…
Abundance and δ13C values of fatty acids in lacustrine surface sediments: Relationships with in-lake methane concentrations
2018
Proxy-indicators in lake sediments provide the only approach by which the dynamics of in-lake methane cycling can be examined on multi-decadal to centennial time scales. This information is necessary to constrain how lacustrine methane production, oxidation and emissions are expected to respond to global change drivers. Several of the available proxies for reconstructing methane cycle changes of lakes rely on interpreting past changes in the abundance or relevance of methane oxidizing bacteria (MOB), either directly (e.g. via analysis of bacterial lipids) or indirectly (e.g. via reconstructions of the past relevance of MOB in invertebrate diet). However, only limited information is availabl…
Assembly, growth and conductive properties of tellurium nanorods produced by Rhodococcus aetherivorans BCP1
2018
AbstractTellurite (TeO32−) is a hazardous and toxic oxyanion for living organisms. However, several microorganisms can bioconvert TeO32− into the less toxic form of elemental tellurium (Te0). Here, Rhodococcus aetherivorans BCP1 resting (non-growing) cells showed the proficiency to produce tellurium-based nanoparticles (NPs) and nanorods (NRs) through the bioconversion of TeO32−, depending on the oxyanion initial concentration and time of cellular incubation. Te-nanostructures initially appeared in the cytoplasm of BCP1 cells as spherical NPs, which, as the exposure time increased, were converted into NRs. This observation suggested the existence of an intracellular mechanism of TeNRs assem…