Search results for "EXPA"
showing 10 items of 820 documents
Asymptotic stability of solutions to Volterra-renewal integral equations with space maps
2012
Abstract In this paper we consider linear Volterra-renewal integral equations (VIEs) whose solutions depend on a space variable, via a map transformation. We investigate the asymptotic properties of the solutions, and study the asymptotic stability of a numerical method based on direct quadrature in time and interpolation in space. We show its properties through test examples.
A Dirichlet problem for the Laplace operator in a domain with a small hole close to the boundary
2016
We study the Dirichlet problem in a domain with a small hole close to the boundary. To do so, for each pair $\boldsymbol\varepsilon = (\varepsilon_1, \varepsilon_2 )$ of positive parameters, we consider a perforated domain $\Omega_{\boldsymbol\varepsilon}$ obtained by making a small hole of size $\varepsilon_1 \varepsilon_2 $ in an open regular subset $\Omega$ of $\mathbb{R}^n$ at distance $\varepsilon_1$ from the boundary $\partial\Omega$. As $\varepsilon_1 \to 0$, the perforation shrinks to a point and, at the same time, approaches the boundary. When $\boldsymbol\varepsilon \to (0,0)$, the size of the hole shrinks at a faster rate than its approach to the boundary. We denote by $u_{\bolds…
Excimer laser atherectomy in an uncrossable long chronic total occlusion through the subintimal space
2020
We present a successfully chronic total occlusions (CTO) coronary recanalisation with the subadventitial space by excimer laser atherectomy (ELCA) adjunctive therapy. Angiogram revealed non-significant diffuse disease of the left coronary system with a complex long proximal right coronary artery (RCA) CTO (J-CTO score 4) and collaterals (Rentrop Grade 2 and Werner classification CC1) from the septal branches (Figure 1, Panel A). CTO PCI of the RCA was then indicated and planned. Initially, antegrade approach and a retrograde approach technique were attempted without success. Thereafter, a rescue Antegrade Dissection Reentry strategy (ADR) was applied. A Pilot 200 (Abbott) was advanced in a …
In situ observations of new particle formation in the tropical upper troposphere: the role of clouds and the nucleation mechanism
2011
New particle formation (NPF), which generates nucleation mode aerosol, was observed in the tropical Upper Troposphere (UT) and Tropical Tropopause Layer (TTL) by in situ airborne measurements over South America (January–March 2005), Australia (November–December 2005), West Africa (August 2006) and Central America (2004–2007). Particularly intense NPF was found at the bottom of the TTL. Measurements with a set of condensation particle counters (CPCs) with different <i>d</i><sub>p50</sub> (50% lower size detection efficiency diameter or "cut-off diameter") were conducted on board the M-55 <i>Geophysica</i> in the altitude range of 12.0–20.5 km and on board …
Macroeconomic fluctuations and educational inequalities in suicide mortality among working-age men in the Baltic countries and Finland in 2000–2015: …
2020
Abstract Introduction In the 2000s, the Baltic countries experienced unprecedented economic growth followed by a deep recession. This study aimed to examine changes and educational inequalities in suicide mortality among working-age men in the Baltic countries and Finland in relation to macroeconomic fluctuations. Methods We analysed changes in overall suicide mortality and by educational level between the 2000–2003, 2004–2007, 2008–2011 and 2012–2015 periods among men aged 30–64 years using census-linked longitudinal mortality data. We estimated age-standardised mortality rates, mortality rate ratios (Poisson regression), the relative index of inequality and slope index of inequality. Resu…
Durability assessment of basalt fiber polymer as reinforcement to expanded clay concrete in harsh environment
2021
Basalt fiber-reinforced polymer composites are receiving considerable attention as they represent a low-cost green source of raw materials. In most cases, fiber-reinforced polymer composites face harsh environments, such as chloride ions in coastal marine environments or cold regions with salt deicing. The resistance of fiber-reinforced polymers subjected to the above environments is critical for the safe design and application of such composites. This research aims to develop a framework to investigate the durability properties of the lightweight expanded clay basalt fiber polymer reinforced concrete exposed to the NaCl environment. The specified quantity of concrete structural elements wa…
A correction method for dynamic analysis of linear systems
2004
Abstract This paper proposes an analytical method to improve the accuracy of the dynamic response of classically damped linear systems, as given by a standard truncated modal analysis. Upon computing the first m undamped modes of a n-degree-of-freedom system, two sets of equations in the Rn nodal space are built, which are uncoupled and govern the contribution to the response of the m computed modes and the remaining (n−m) unknown modes, respectively. The first set is solved in the Rm modal space by using the m available modes; the second set is solved in a reduced R(n−m) nodal space, without computing additional modes. Specifically, it is shown that the particular solution of the second se…
The influence of the cycloid disc bearing type on the cycloidal speed reducer efficiency
2021
The robotics industry has experienced a rapid expansion in the last decade. As a result, the market of speed reducers with high gear ratios, high precision and a compact design is growing rapidly. In addition to these characteristics, it is very important for gear trains to have high efficiency. Because of their compact design, cycloidal speed reducers are not exposed to axial forces, which is their important characteristic. This means that radial bearings can be used in their supports. The bearing type has significant effects not only on the design and dimensions of the cycloid speed reducer but also on its efficiency. In this paper, an analysis of power losses for different types of rolli…
Empirical molecular dynamics study of structural, elastic and thermodynamic properties of zinc-blende-like SiGe compound
2004
Abstract A three-body potential coupled with a molecular-dynamics method is used to calculate structural and thermodynamic properties of the hypothetical IV–IV compound SiGe in zinc-blende phase. A good agreement between the calculated and theoretical values of the lattice constant, the bulk modulus and its derivative, and the cohesive energy is obtained. We also compute the elastic constants, Debye temperature, lattice thermal expansion, and the specific heat. We investigate also, the structural properties of SiGe when rock-salt phase appears.
Bioactive compounds from mustard flours for the control of patulin production in wheat tortillas
2016
Abstract Patulin (PAT) is a toxic fungal metabolite produced by Penicillium, Aspergillus and Byssochlamys growing especially in fruit and cereals. PAT exhibits a number of toxic effects in animals and its presence in food is undesirable. In this study the reduction of the mycotoxin PAT produced by a strain of Penicillium expansum, on wheat tortillas was studied using volatile bioactive compounds present in the oriental and yellow mustard flour and also using the standard solution of the antifungal compound allyl isothiocyanate (AIT), developing an active packaging with two different systems of release of those bioactive compounds. Also the kinetic of volatilization of the compounds used in …