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.62), whereas average craving tool use was of 3.22 ± 1.67 times with an average of 38.25 ± 49 modules completed for the low-use sample. Data analysis Computational modeling As in

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.V. Byrne Y. Ventikos 2008 The haemodynamics of endovascular aneurysm treatment: a computational modelling approach for estimating the influence of multiple coil

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The temperature field calculation of the diesel engine piston could be calculated depending on formula ( 18 ). The computational model and boundary conditions After the crude oil entered the storage tank and the status of

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Abstract  

The University of Texas at Austin Neutron Depth Profiling (UT-NDP) facility was utilized to analyze varying cathode compositions in lithium battery materials. Battery materials included LiCoO2, LiMn1/3Ni1/3Co1/3O2, and LiFePO4. The cells were made at The University of Texas at Austin as coin cells with lithium anodes. The NDP analysis method for Li in battery materials was benchmarked between two facilities and with computational models.

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In the pond snail Lymnaea stagnalis, a firm phase-locked coupling of pneumostome movements to the locomotor cycle was observed during terrestrial locomotion, thus demonstrating that the coordination between locomotor and respiratory rhythms is a natural behavioral event in this animal. The results of computational modelling suggest a possible scheme of coordination between these motor rhythms which is based on inhibitory projection from the central pattern generator for locomotion to that for respiration. These findings allow the neuronal mechanisms underlying coordination of two rhythmic behaviors to be investigated.

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abstract  

The results of computational modeling and experimental data on some thermophysical properties of selected polymers were compared. Different engineering polymers, e.g. polycarbonates and terephthalate polyesters, were considered and their glass transition temperatures and thermal stabilities were determined, by using thermoanalytical methods, e.g. DSC and TG. Measurements were carried out with Perkin-Elmer DSC 7 and TGA 7 instruments. Molecular modeling and computer calculations were performed at the Interdisciplinary Computer Modeling Center (ICM) of Warsaw University, using a Cray El 98 computer and the Insight II software of BIOSYM Technologies Inc. Reasonably good agreement was found between the experimental and calculated values of the glass transition temperatures of the investigated polymers, e.g. for poly(butylene terephthalate)T g (calc.)=74‡C andT g (experim.)=70‡C. Discrepancies were observed for the temperature of half decompositionT d,1/2, some of them can be explained by effects of polymer molecular weight and/or char-forming effects.

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Graduate students in the Mechanical Engineering department at the University of Texas at Austin have designed and modeled a fast neutron prompt-gamma activation analysis facility as part of a new course introduced in the graduate program titled “The Design of Nuclear Systems.” The students were responsible for creating a design concept as well as implementing and modeling the concept to ensure its safety and functionality. The purpose of the class was to give graduate students the independence to create a project of their own vision, but to do so in a collaborative and formal manner as will be necessary in their future work. The fast neutron PGAA facility was successfully designed and computational models have been analyzed to display benefits of the fast neutron facility compared to the thermal neutron PGAA facility that also exists at The University of Texas at Austin.

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Abstract

Lifts are indispensable for the evacuation of mobility-impaired people from buildings in case of emergency. It is necessary to quantify the movement parameters of these people and describe the entire process using a suitable algorithm. The aim of the research was to quantify the times and speeds of movement for a person using a wheelchair and for an injured person. An experiment in situ was used. During the experiment, arrivals at the lift, cabin entries, and exits were monitored. The results include the times and speeds of a mobility-impaired person's movement. The experiments showed that a person using a wheelchair was slower than an injured person. The results can be used to expand computational models to account for the possibility of using lifts for evacuation.

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Dolgozatomban a teljesség igénye nélkül áttekintem a figyelem megosztásával (concurrent multitasking) foglalkozó pszichológiai irodalmat. Klasszikus vizsgálatokból és alapvető kísérleti paradigmákból kiindulva felvázolom a nagyobb elméletek (üvegnyak- és kapacitásmegosztó elméletek és komputációs modellek) történetét és jelenlegi helyzetét. Dolgozatom végén külön foglalkozom a gyakorlásnak a párhuzamos feldolgozásra gyakorolt feltételezett hatásaival.

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Interventional Medicine and Applied Science
Authors:
Róbert Bordás
,
Santhosh Seshadhri
,
Gábor Janiga
,
Martin Skalej
, and
Dominique Thévenin

Abstract

The treatment of cerebral aneurysms, found in roughly 5% of the population and associated in case of rupture to a high mortality rate, is a major challenge for neurosurgery and neuroradiology due to the complexity of the intervention and to the resulting, high hazard ratio. Improvements are possible but require a better understanding of the associated, unsteady blood flow patterns in complex 3D geometries. It would be very useful to carry out such studies using suitable numerical models, if it is proven that they reproduce accurately enough the real conditions. This validation step is classically based on comparisons with measured data. Since in vivo measurements are extremely difficult and therefore of limited accuracy, complementary model-based investigations considering realistic configurations are essential. In the present study, simulations based on computational fluid dynamics (CFD) have been compared with in situ, laser-Doppler velocimetry (LDV) measurements in the phantom model of a cerebral aneurysm. The employed 1:1 model is made from transparent silicone. A liquid mixture composed of water, glycerin, xanthan gum and sodium chloride has been specifically adapted for the present investigation. It shows physical flow properties similar to real blood and leads to a refraction index perfectly matched to that of the silicone model, allowing accurate optical measurements of the flow velocity. For both experiments and simulations, complex pulsatile flow waveforms and flow rates were accounted for. This finally allows a direct, quantitative comparison between measurements and simulations. In this manner, the accuracy of the employed computational model can be checked.

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