Search results for "fixed"
showing 10 items of 639 documents
Trial Methods for Nonlinear Bernoulli Problem
1997
In this article we consider a free boundary problem which is related to formation of waves on a fluid surface (for example the ship waves). We study the possibility to construct ‘trial’ methods where one solves a sequence of standard flow problems formulated in different geometries that converge to the final free boundary. Furthermore, we use the shape optimization techniques to analyse the convergence of the fixed point iteration near a fixed point. For stream function case we conclude that the fast convergence can be obtained by using non-standard boundary conditions and we present numerical results to confirm the analysis.
Host–virus evolutionary dynamics with specialist and generalist infection strategies: Bifurcations, bistability, and chaos
2019
In this work, we have investigated the evolutionary dynamics of a generalist pathogen, e.g., a virus population, that evolves toward specialization in an environment with multiple host types. We have particularly explored under which conditions generalist viral strains may rise in frequency and coexist with specialist strains or even dominate the population. By means of a nonlinear mathematical model and bifurcation analysis, we have determined the theoretical conditions for stability of nine identified equilibria and provided biological interpretation in terms of the infection rates for the viral specialist and generalist strains. By means of a stability diagram, we identified stable fixed…
Influence of a collagen membrane and recombinant platelet-derived growth factor on vertical bone augmentation in implant-fixed deproteinized bovine b…
2012
Combinations of bone substitute block materials with membrane techniques as well as with growth factors are possible options to enhance the prognosis of vertical bone augmentation. Therefore, the aim of the pilot study was to compare the influence of a collagen membrane and a signal protein (rhPDGF-BB) on vertical bone augmentation with a stable fixed block material (deproteinized bovine bone [DBB]).In 12 rabbits, a DBB-block was implant-fixed on the tibia in a split-leg-design. Included were: DBB only (control), DBB + collagen membrane (test), DBB + rhPDGF-BB (test) and DBB + rhPDGF-BB + collagen membrane (test). 24 samples were examined after 3 (n = 12) and 6 weeks (n = 12). Calculated pa…
Brightness and contrast do not affect visually induced motion sickness in a passively-flown fixed-base flight simulator
2016
Abstract Background Visually Induced Motion Sickness (VIMS) or simulator sickness is often elicited by a visual stimulus that lacks the appropriate vestibular or proprioceptive feedback. In this study, we chose to investigate the effects of brightness and contrast of the visual scene on VIMS. Hypothesis We hypothesized that visual environments differing in brightness or contrast would differentially induce VIMS. The symptoms of VIMS should be most severe for the combination of high brightness and high contrast and conversely lowest for the low brightness and low contrast condition. Methods 33 healthy subjects were tested in a fixed-base flight simulator. Each subject flew in four consecutiv…
Tirdzniecības atvērtības ietekme uz ekonomikas izaugsmi, CAE valstu empīriskais pētījums
2021
Darba mērķis ir izpētīt tirdzniecības atvērtības ietekmi uz ekonomikas izaugsmi, izmantojot 16 Centrālās un Austrumeiropas valstu paneļa datus 2010. – 2019. gadā, salīdzinot 4 dažādus tirdzniecības atvērtības rādītājus. Apvienotie OLS un fiksētie efekti tiek izmantoti kā primārie novērtētāji, un noturības analīzei tiek izmantots sistēmas GMM tests. Apkopoto OLS un fiksēto šķērsgriezumu regresiju iegūtie rezultāti parāda, ka dažādos tirdzniecības atvērtības mērījumos tirdzniecības atvērtība pozitīvi un ļoti nozīmīgi ietekmē ekonomikas izaugsmi. GMM sistēmas testi parāda tirdzniecības atvērtības negatīvo ietekmi uz ekonomikas izaugsmi, bet nozīmīgumu ieguva tikai divi atvērtības rādītāji.
Efficacy of tiotropium and olodaterol fixed-dose combination in patients with COPD on β-blockers
2015
Introduction: The efficacy and safety of a new once-daily (QD) fixed-dose combination (FDC) with tiotropium (T), a long-acting muscarinic antagonist, and olodaterol (O), a long-acting β 2 -agonist, was established for the treatment of COPD in the TONADO studies (NCT01431274; NCT01431287). This analysis evaluates the efficacy of the FDC in a subpopulation of patients receiving β-blockers (BBs) in these studies. Methods: Two replicate, randomised, double-blind, parallel-group, 52-week, Phase III trials assessed the efficacy and safety of T+O FDC (2.5/5 μg; 5/5 μg; Respimat ® inhaler) QD compared to the monocomponents. Key primary end point data for the combined analysis of the replicate trial…
Stochastic sensitivity of bull and bear states
2021
We study the price dynamics generated by a stochastic version of a Day–Huang type asset market model with heterogenous, interacting market participants. To facilitate the analysis, we introduce a methodology that allows us to assess the consequences of changes in uncertainty on the dynamics of an asset price process close to stable equilibria. In particular, we focus on noise-induced transitions between bull and bear states of the market under additive as well as parametric noise. Our results are obtained by combining the stochastic sensitivity function (SSF) approach, a mixture of analytical and numerical techniques, due to Mil’shtein and Ryashko (1995) with concepts and techniques from th…
Evaluation of Small Vase and Y-trellis Orchard Systems for Peach and Nectarine Production in Mediterranean Regions
2015
Two peach planting systems, Small Vase (SV) and Y-trellis (Y), were evaluated and compared in the Mediterranean settings of Southern Italy. The two orchards were located next to each other on relatively uniform soil and terrain, and the observations included two peach (âRich Mayâ and âSummer Richâ) and two nectarine (âBig Bangâ and âNectarossâ) cultivars. In the SV system, trees were spaced at 4.5 A 2.5 m (888 trees/ha), whereas in the Y system, trees were spaced at 5.5 A 2 m (909 trees/ha) and no canopy gap was left between rows. Yield per tree; fruit size grade; unit price of sold peaches for each size grade; materials, labor and associated costs for cultural management;…
INTEGRAL SOLUTIONS TO A CLASS OF NONLOCAL EVOLUTION EQUATIONS
2010
We study the existence of integral solutions to a class of nonlinear evolution equations of the form [Formula: see text] where A : D(A) ⊆ X → 2X is an m-accretive operator on a Banach space X, and f : [0, T] × X → X and [Formula: see text] are given functions. We obtain sufficient conditions for this problem to have a unique integral solution.
Rotation correlation time as a measure of microviscosity of excited state isomerization reactions of three cyanine dyes in n-alcohol solutions
1994
Abstract Rotation correlation times of three chemically similar cyanine dyes of different sizes in n -alcohol solutions have been recorded at several temperatures by using polarized picosecond spectroscopy. For all three dyes the linear temperature dependencies of τ or on η/ T were observed to be independent of solvent up to viscosities of about 60 cP. The rotational motion of the dyes proceeds at much slower rates than the excited state isomerization in viscous solutions of the same fluidity. Isomerization seems to depend on special solvent-induced changes of the force field of the reactant and clearly proceeds faster, especially for the two larger dyes, than predicted by Kramers' theory a…