527 research outputs found
Newton and Bouligand derivatives of the scalar play and stop operator
We prove that the play and the stop operator possess Newton and Bouligand
derivatives, and exhibit formulas for those derivatives. The remainder estimate
is given in a strenghtened form, and a corresponding chain rule is developed.
The construction of the Newton derivative ensures that the mappings involved
are measurable
Hopf bifurcations and simple structures of periodic solution sets in systems with the Preisach nonlinearity
We survey a number of recent results and suggest some new ones on periodic solutions of systems with hysteresis. The main focus of this work is the situation when simple one-parameter structures of periodic regimes appear. We consider forced oscillations, cycles of autonomous systems and Hopf bifurcations from the equilibrium and from infinity
Newton and Bouligand derivatives of the scalar play and stop operator
We prove that the play and the stop operator possess Newton and Bouligand derivatives, and exhibit formulas for those derivatives. The remainder estimate is given in a strengthened form, and a corresponding chain rule is developed. The construction of the Newton derivative ensures that the mappings involved are measurable
On the Mróz Model
We treat the mathematical properties of the one parameter version of the Mróz model for plastic flow. We present continuity results and an energy inequality for the hardening rule and discuss different versions of the flow rule regarding their relation to the second law of thermodynamics
Asymptotic stability of continual sets of periodic solutions to systems with hysteresis
We consider hysteresis perturbations of the system of ODEs which has an asymptotically stable periodic solution . It is proved that if the oscillation of the appropriate projection of is smaller than some threshold number defined by the hysteresis nonlinearity, then the perturbed system has a continuum of periodic solutions with a rather simple structure in a vicinity of . The main result is the theorem on stability of this continuum
An alternative to the Allen-Cahn phase field model for interfaces in solids - numerical efficiency
The derivation of the Allen-Cahn and Cahn-Hilliard equations is based on the
Clausius-Duhem inequality. This is not a derivation in the strict sense of the
word, since other phase field equations can be fomulated satisfying this
inequality. Motivated by the form of sharp interface problems, we formulate
such an alternative equation and compare the properties of the models for the
evolution of phase interfaces in solids, which consist of the elasticity
equations and the Allen-Cahn equation or the alternative equation. We find that
numerical simulations of phase interfaces with small interface energy based on
the alternative model are more effective then simulations based on the
Allen-Cahn model.Comment: arXiv admin note: text overlap with arXiv:1505.0544
Some analytical properties of the multidimensional continuous Mróz model of plasticity
We study the geometrical structure of memory induced by the continuous multidimensional Mr'oz model of plasticity. The results are used for proving the thermodynamic consistency of the model and composition and inversion formulas for input - memory state - output operators. We also show an example of nonuniqueness of solutions to a simple initial value problem involving the Mr'oz operator
A customer's view on policy measures to promote electric vehicles
Electric vehicles represent a promising approach to reduce local vehicle emissions, and thus to improve air quality in urban regions. Their market uptake, however, is still staying below expectations in most countries across Europe, due to monetary and non-monetary barriers. Besides monetary incentives, different non-monetary policy measures to promote electric mobility are either discussed or already in place. Since the different monetary incentives across Europe have proven to be not equally effective in the support of the electric vehicle market uptake, it is expected that non-monetary policy measures will not express the same impact level in different countries, too. Therefore, the project "Incentives for Cleaner Vehicles in Urban Europe" (I-CVUE) aims to understand the efficacy of policy measures that promote electric vehicles in Europe. In order to gain a deeper understanding a stated preference survey was executed that focusses on studying the value of policy measures and further non-monetary aspects of electric vehicle ownership. The online survey was directed at vehicle drivers and fleet managers in Austria, Germany, the Netherlands, the United Kingdom, and Spain. Based on the obtained data, country-specific willingness-to-pay values are deducted, which can be used to assess the utility of electric vehicles. The results are used to derive recommendations to city-level policy makers on efficient measures to promote electric vehicles
Cytoplasmic LSM-1 protein regulates stress responses through the insulin/IGF-1 signaling pathway in Caenorhabditis elegans
This article is distributed exclusively by the RNA Society for the first 12 months after the full-issue publication date. After 12 months, it is available under a Creative Commons License (Attribution-NonCommercial 4.0 International).-- et al.Genes coding for members of the Sm-like (LSm) protein family are conserved through evolution from prokaryotes to humans. These proteins have been described as forming homo-or heterocomplexes implicated in a broad range of RNA-related functions. To date, the nuclear LSm2-8 and the cytoplasmic LSm1-7 heteroheptamers are the best characterized complexes in eukaryotes. Through a comprehensive functional study of the LSm family members, we found that lsm-1 and lsm-3 are not essential for C. elegans viability, but their perturbation, by RNAi or mutations, produces defects in development, reproduction, and motility. We further investigated the function of lsm-1, which encodes the distinctive protein of the cytoplasmic complex. RNA-seq analysis of lsm-1 mutants suggests that they have impaired Insulin/IGF-1 signaling (IIS), which is conserved in metazoans and involved in the response to various types of stress through the action of the FOXO transcription factor DAF-16. Further analysis using a DAF-16:GFP reporter indicated that heat stress-induced translocation of DAF-16 to the nuclei is dependent on lsm-1. Consistent with this, we observed that lsm-1 mutants display heightened sensitivity to thermal stress and starvation, while overexpression of lsm-1 has the opposite effect. We also observed that under stress, cytoplasmic LSm proteins aggregate into granules in an LSM-1-dependent manner. Moreover, we found that lsm-1 and lsm-3 are required for other processes regulated by the IIS pathway, such as aging and pathogen resistance.This work was supported by a grant from the Instituto de Salud Carlos III (ISCIII) (Exp. PI12/01554). R.J. and D.B. were supported by a Natural Sciences and Engineering Research Council (NSERC) Canada grant. D.B. holds a Canada Research Chair. J.C. is a Miguel Servet Researcher (ISCIII). E.C. was supported with a CTP-AIRE fellowship from AGAUR (Generalitat de Catalunya) and a TRANSBIO SUDOE collaborative project.Peer Reviewe
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