Search results for "Step"
showing 10 items of 509 documents
One-step reactive processing of low density polyethylene and octavinyl polyhedral oligomeric silsesquioxane
2015
Polyhedral oligomeric silsesquioxane (POSS) are an innovative class of organosilicon compounds suitable for formulation of advanced organic-inorganic hybrid materials. Nanocomposites based POSS found application mostly in high-temperature resistance and fire-resistance materials. POSS are characterized by a three dimensional cage-like structure, made of Si-O bonds, with different organic groups directly linked to the Si atoms of the cage structure. The organic groups can be designed to facilitate the dispersion of the nanoparticle itself in the polymer matrix or also to react with the polymer chain. This work focuses on the possibility to obtain crosslinking of polyethylene using octavinyl-…
Existence and stability of periodic solutions in a neural field equation
2017
We study the existence and linear stability of stationary periodic solutions to a neural field model, an intergo-differential equation of the Hammerstein type. Under the assumption that the activation function is a discontinuous step function and the kernel is decaying sufficiently fast, we formulate necessary and sufficient conditions for the existence of a special class of solutions that we call 1-bump periodic solutions. We then analyze the stability of these solutions by studying the spectrum of the Frechet derivative of the corresponding Hammerstein operator. We prove that the spectrum of this operator agrees up to zero with the spectrum of a block Laurent operator. We show that the no…
Chalcogenide Photonic Crystal Fibers for Near and Middle Infrared Applications
2007
Chalcogenide glasses are based on sulphur, selenium, tellurium and the addition of other elements such as arsenic, germanium, antimony, gallium, etc. Chalcogenide fibers present numerous applications in the IR field, such as telecommunication at 1.55 mum, spectroscopy and military systems in the two atmospherics windows (3-5 mum and 8-12 mum). One of the interests of chalcogenide glasses is to associate high non linear properties with their Infrared transmission from 0.51 mum to 12-18 mum depending on the composition. Indeed, chalcogenide glasses present high third order optical properties, 100 - 1000 times as high as the non linearity of silica glass at 1.55 mum. For many applications, sin…
Static output-feedback control for vehicle suspensions: a single-step linear matrix inequality approach
2013
In this paper, a new strategy to design static output-feedback controllers for a class of vehicle suspension systems is presented. A theoretical background on recent advances in output-feedback control is first provided, which makes possible an effective synthesis of static output-feedback controllers by solving a single linear matrix inequality optimization problem. Next, a simplified model of a quarter-car suspension system is proposed, taking the ride comfort, suspension stroke, road holding ability, and control effort as the main performance criteria in the vehicle suspension design. The new approach is then used to design a static output-feedbackH∞controller that only uses the suspensi…
Estimating trematode prevalence in snail hosts using a single-step duplex PCR: how badly does cercarial shedding underestimate infection rates?
2014
Background: Trematode communities often consist of different species exploiting the same host population, with two or more trematodes sometimes co-occuring in the same host. A commonly used diagnostic method to detect larval trematode infections in snails has been based on cercarial shedding, though it is often criticized as inaccurate. In the present study we compare infection prevalences determined by cercarial emission with those determined, for the first time, by molecular methods, allowing us to quantify the underestimation of single and double infections based on cercarial emission. We thus developed a duplex PCR for two host-parasite systems, to specifically differentiate between sin…
A human factors intervention in a hospital - evaluating the outcome of a TeamSTEPPS program in a surgical ward
2021
AbstractBackgroundPatient safety in hospitals is being jeopardized, since too many patients experience adverse events. Most of these adverse events arise from human factors, such as inefficient teamwork and communication failures, and the incidence of adverse events is greatest in the surgical area. Previous research has shown the effect of team training on patient safety culture and on different areas of teamwork. Limited research has investigated teamwork in surgical wards. The aim of this study was to evaluate the professional and organizational outcomes of a team training intervention among healthcare professionals in a surgical ward after 6 and 12 months. Systems Engineering Initiative…
Dehydration of mildronate dihydrate: a study of structural transformations and kinetics
2014
The dehydration of mildronate dihydrate (3-(1,1,1-trimethylhydrazin-1-ium-2-yl)propionate dihydrate) was investigated by powder X-ray diffraction, thermal analysis, hot-stage microscopy, water sorption–desorption studies and dehydration kinetic studies. It was determined that mildronate dihydrate dehydrated in a single step, directly transforming into the anhydrous form. In order to understand the reasons for a one step dehydration mechanism, crystal structures of dihydrate, monohydrate and anhydrous forms were compared, proving the similarity of the dihydrate and anhydrous forms. In order to understand the reasons for molecule reorganization during dehydration, the energy of the anhydrous …
Structural Signatures of Type IV Isotherm Steps: Sorption of Trichloroethene, Tetrachloroethene, and Benzene in Silicalite-I
2002
We have investigated by in situ neutron diffraction the structural properties of C2HCl3, C2Cl4, and C6D6 sorbed phases in silicalite-1. Our motivation is to correlate the structure of these three confined species to the fact that their adsorption isotherms are characterized by no step, one step, and two steps, respectively. From our detailed neutron diffraction investigation, we deduce that the adsorption isotherm steps are not signatures of phase transitions but are correlated to the different adsorption stages observed during the silicalite-1 loading. For C6D6, such a loading is a three stage process (the C6D6 molecules fill successively, the intersections, then the straight channels and …
La vida cotidiana de los vecinos de Manila a través de sus testamentos e inventarios de bienes
2019
With the general objective indicated in its title, this work tries to highlight relevant aspects in the continuity of the Spanish domain in the Philippines, dependent on the maintenance of the Spanish capital. The inevitable selection of topics has lead the preferences of this work towards the residents collaboration to defend the city, the conversion of many of them into traders of exotic products and singular slaves owners, and their collaboration to an incredible miscegenation due to the ethnic variety. On the other hand, to follow the footsteps of the first generation of residents in Manila, at the end of the 16th century and during the 17th century, this work gives us some information …
Entrevista con Stephen E. Toulmin
1993
El texto que sigue reproduce -prácticamente sin ninguna alteración- la entrevista oral realizada por los autores a Stephen E. Toulmin, con ocasión de la estancia de este último en Madrid, en diciembre de 1992, para participar en el congreso sobre Las crisis de la justicia, organizado por el Consejo General del Poder Judicial. La traducción castellana de la grabación magnetofónica corri6 a cargo de Manuel Jiménez Redondo.