Search results for "linear"
showing 10 items of 7165 documents
The dissipative linear Boltzmann equation for hard spheres
2005
The authors prove existence and uniqueness of a Maxwellian, normalized equilibrium state for a dissipative linear Boltzmann equation with hard-sphere collision kernel modeling a granular gas and, for initial data with finite temperature and entropy, strong L 1 convergence (obtained through compactness arguments) toward the equilibrium of the solutions in the space-homogeneous case. The form of the equilibrium state, which is universal for the family of collision operators including hard, soft and Maxwellian interactions, is guessed through a grazing collision asymptotics and then proved to be the equilibrium state through Fourier analysis. Uniqueness and strong L 1 convergence proofs follow…
Liquid Phase Micro-Extraction of Linear Alkylbenzene Sulfonate Anionic Surfactants in Aqueous Samples
2011
Hollow fiber liquid phase micro-extraction (LPME) of linear alkylbenzene sulfonates (LAS) from aqueous samples was studied. Ion pair extraction of C10, C11, C12 and C13 homologues was facilitated with trihexylamine as ion-pairing agent, using di-n-hexylether as solvent for the supported liquid membrane (SLM). Effects of extraction time, acceptor buffer concentration, stirring speed, sample volume, NaCl and humic acids were studied. At 10–50 µg L−1 linear R2-coefficients were 0.99 for C10 and C11 and 0.96 for C12. RSD was typically ~15%. Three observations were especially made. Firstly, LPME for these analytes was unusually slow with maximum enrichment observed after 15–24 h (depending on sa…
PALERMO 2019: GREEN LINE
2017
L'organizzazione di un Laboratorio internazionale di Progettazione Architettonica ha rivelato l'importanza di accostare figure provenienti dal mondo accademico e istituzionale ancor prima che Palermo presentasse la sua proposta di candidatura a Capitale Europea della Cultura 2019. Questa esperienza, che si è rivelata utile per definire alcuni spazi incerti della città, è risultata assai stimolante per la comunità scientifica e per le istituzioni coinvolte. La consapevolezza del ruolo di servizio e di indirizzo che la comunità scientifica deve assumersi nei confronti del proprio territorio, i rimando ai temi che riguardano l'architettura e il territorio della città mediterranea, l'attenzione…
Pairwise and higher-order measures of brain-heart interactions in children with temporal lobe epilepsy
2022
Abstract Objective. While it is well-known that epilepsy has a clear impact on the activity of both the central nervous system (CNS) and the autonomic nervous system (ANS), its role on the complex interplay between CNS and ANS has not been fully elucidated yet. In this work, pairwise and higher-order predictability measures based on the concepts of Granger Causality (GC) and partial information decomposition (PID) were applied on time series of electroencephalographic (EEG) brain wave amplitude and heart rate variability (HRV) in order to investigate directed brain-heart interactions associated with the occurrence of focal epilepsy. Approach. HRV and the envelopes of δ and α EEG activity re…
Stability, electronic structure, and optical properties of protected gold-doped silver Ag29-xAux (x = 0-5) nanoclusters
2017
In this work, we used density functional theory (DFT) and linear response time-dependent DFT (LR-TDDFT) to investigate the stability, electronic structure, and optical properties of Au-doped [Ag29−xAux(BDT)12(TPP)4]3− nanoclusters (BDT: 1,3-benzenedithiol; TPP triphenylphosphine) with x = 0–5. The aim of this work is to shed light on the most favorable doped structures by comparing our results with previously published experimental data. The calculated relative energies, ranging between 0.8 and 10 meV per atom, indicate that several doped Ag29−xAux nanoclusters are likely to co-exist at room temperature. However, only the Au-doped [Ag29−xAux(BDT)12(TPP)4]3− nanoclusters that have direct bon…
Algebriskās nevienādības 11. klases matemātikas mācību riekšmeta saturā
2016
Bakalaura darba mērķis: Atbalsta materiālu izveide efektīvākai tēmas „Algebriskas nevienādības” apguvei. Lai sasniegtu darba mērķi, autore veica pētījumu, aptaujājot 13 matemātikas skolotājas no trīs novadu skolām. Analizējot aptauju, autore noskaidroja matemātikas skolotāju viedokli par tēmas „Algebriskas nevienādības” mācību procesu. Autore secināja, ka tēma „Algebriskas nevienādības” skolēniem ir saprotama, ja ir stabilas un labas pamatzināšanas no pamatskolas kursa. Visnozīmīgākais tēmas apguvē ir skolēnu patstāvīgais darbs, kā arī mācību stundā uzdotie mājas darbi zināšanu nostiprināšanai. Izanalizējot matemātikas skolotāju ieteikumus, autore izstrādāja atbalsta materiālus, kas veicina…
PUASONA VIENĀDOJUMA RISINĀŠANA ELEKTRONU STRUKTŪRAS SIMULĀCIJĀS AR DAŽĀDU PERIODISKUMU
2022
Puasona vienādojuma risināšana ir neatņemama elektronu struktūras aprēķinu sastāvdaļa. Atkarībā no pētāmās sistēmas periodiskuma, elektrostatiskajam potenciālam ir izdevīgi pielietot dažādus robežnosacījumus, taču pievienoto plakano viļņu bāzē Puasona vienādojumu risina, izmantojot periodiskus robežnosacījumus. Šajā darbā es implementēju Puasona vienādojuma risināšanas metodes, kas ir piemērotas arī aprēķinos joniem, molekulām, polimēriem un divdimensiju materiāliem. Šāda pieeja saglabā augstu precizitāti, arī samazinot vienības šūnas izmēru. Demonstrēju lielu ieguvumu nelokālas apmaiņas aprēķinos, izmantojot manu implementēto metodi.
MR3631681 Reviewed Nigsch, E. A.(A-WIENM) On a nonlinear Peetre's theorem in full Colombeau algebras. (English summary) Comment. Math. Univ. Carolin.…
2017
Colombeau algebras are defined as quotients of spaces containing the representatives of generalized functions given by smooth mappings: R:C∞(Ω,D(Ω))→C∞(Ω), where Ω is an open subset of Rn. In this paper the notion of locality defined by the author for a representative R of a nonlinear generalized function is characterized in such a way that the representative depends only on its ∞-jet. Finally, the author examines the possibility of defining a notion of order for the mapping R.
On a Robin (p,q)-equation with a logistic reaction
2019
We consider a nonlinear nonhomogeneous Robin equation driven by the sum of a \(p\)-Laplacian and of a \(q\)-Laplacian (\((p,q)\)-equation) plus an indefinite potential term and a parametric reaction of logistic type (superdiffusive case). We prove a bifurcation-type result describing the changes in the set of positive solutions as the parameter \(\lambda \gt 0\) varies. Also, we show that for every admissible parameter \(\lambda \gt 0\), the problem admits a smallest positive solution.
Computation of lock-in range for classic PLL with lead-lag filter and impulse signals
2016
For a classic PLL with square waveform signals and lead-lag filter for all possible parameters lock-in range is computed and corresponding diagrams are given. peerReviewed