Personal multimedia services over a common home and access networking environment

This article presents a new end-to-end architecture model that will enable the deployment of a plethora of different multimedia services from diverse suppliers competitively coexisting over a common access and home networking environment. The model is focused on personal multimedia communication services and terminals. The proposed model is a segmentation of the end-to-end multimedia chain into several business segments. The interfaces among segments and functional entities inside each segment are identified and defined in the work. In order to study the impact level of the results achieved, a comparison with the approximation to NGN provided by current standardization bodies in the field (3GPP and TISPAN) is also included in the article. This comparison highlights the advantages of using this model as a solution to offer PMC services.     

A numerical analysis of muzzle blast precursor flow

A new computational technique, involving the formation of grids by conformal mappings, the use of the λ-scheme and of shock fittings is applied to solve the Navier-Stokes equations which describe the flow field behind the precursor shock consequent to the firing of a gun, until the bullet is entirely out of the barrel. The numerical analysis is presented in detail and reasons for the choice of the technique are discussed. Three examples are presented, discussed and compared with experimental results.     

High-velocity transport of nanoparticles through 1-D nanochannels at very large particle to channel diameter ratios

We explore the possibility of generating high-velocity flows of nanoparticles through flat-rectangular nanochannels, which are only 50% deeper than the diameter of the particles. Using the shear-driven flow principle, 200-nm particles can, for example, be transported through a 300-nm-deep channel at velocities up to 35 mm/s (upper limit of our current setup). Working under high-pH conditions, the velocity of the carboxylated nanoparticles still respects the small-molecule velocity law, despite the high degree of confinement to which the particles are subjected. The high degree of confinement is also found to lead to a reduced band broadening. When injecting sharply delimited particle plugs, the plate heights observed for the flow of 0.2-microm particles through a 0.3-microm channel (with plate heights of the order of 1-2 microm) are, for example, approximately 1 order of magnitude smaller than for the flow of 1.0-microm particles through a 1.4-microm channel. It is also found that the band broadening is, within its statistical variation, independent of the fluid velocity over a large range of particle velocities (5-35 mm/s). The flow method distinguishes itself from pressure-driven field-flow fractionation and hydrodynamic chromatography in that the mean particle velocity is independent of the particle size over the entire range of possible particle to channel diameter ratios.     

Importance and reduction of the sidewall-induced band-broadening effect in pressure-driven microfabricated columns

The influence of the detailed design of the sidewall region upon the over-all band-broadening in microfabricated packed-bed or collocated monolithic support structure (COMOSS) columns has been investigated using computational fluid dynamics (CFD) simulation techniques. It is shown that, under unretained solute conditions, very small structural variations of the order of only 5% of the particle diameter can give rise to a 4-fold increase of the band-broadening. A comprehensive study has been made to quantify this effect as a function of the fluid velocity, the particle diameter, the channel widths, and of course, the sidewall region design. Because the sidewall effect can be fully attributed to a mismatch between the flow rates in the column center and in the sidewall region, it is fortunately also quite straightforward to avoid it. A very simple design, yielding band-broadening values identical to that of a hypothetical sidewall-less column for all possible values of the flow velocity, the particle diameter, or the channel width is proposed.     

Design and preparation of μ‐bimodal porous scaffold for tissue engineering

The aim of this study was to prepare poly‐?‐caprolactone (PCL) foams, with a well‐defined micrometric and bimodal open‐pore dimension distribution, suitable as scaffolds for tissue engineering. The porous network pathway was designed without using toxic agents by combining gas foaming (GF) and selective polymer extraction techniques. PCL was melt‐mixed with thermoplastic gelatin (TG) in concentrations ranging from 40 to 60 wt %, to achieve a cocontinuous blend morphology. The blends were subsequently gas foamed by using N₂‐CO₂ mixtures, with N₂ amount ranging from 0 to 80 vol %. Foaming temperature was changed from 38 to 110°C and different pressure drop rates were used. After foaming, TG was removed by soaking in H₂O. The effect of blend compositions and GF process parameters on foam morphologies was investigated. Results showed that different combinations of TG weight ratios and GF parameters allowed the modulation of macroporosity fraction, microporosity dimension, and degree of interconnection. By optimizing the process parameters it was possible to tailor the morphologies of highly interconnected PCL scaffolds for tissue engineering. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Proposed Framework for Evaluating Quality of Experience in a Mobile,Testbed-oriented Living Lab Setting

The framework presented in this paper enables the evaluation of Quality of Experience (QoE) in a mobile, testbed-oriented Living Lab setting. As a result, it fits within the shift towards more user-centric approaches in innovation research and aims to bridge the gap between technical parameters and human experience factors. In view of this, Quality of Experience is seen as a multi-dimensional concept, which should be considered from an interdisciplinary perspective. Although several approaches for evaluating perceived QoE have been proposed in the past, they tend to focus on a limited number of objective dimensions and fail to grasp the subjective counterparts of users’ experiences. We therefore propose a distributed architecture for monitoring network Quality of Service (QoS), context information and subjective user experience based on the functional requirements related to real-time experience measurements in real-life settings. This approach allows us to evaluate all relevant QoE-dimensions in a mobile context.     

Poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate)/Poly-L-lactide blends: Thermal and mechanical properties

Blends of poly(3-hydroxybutyrate)–poly(3-hydroxyvalerate) (PHBV) and poly(L -lactides) (PLLA) have been prepared by solvent casting. Compatibility, thermal behavior, morphology, and mechanical properties of systems with various compositions were studied using differential scanning calorimetry (DSC), dynamic mechanical measurement, tensile tests, scanning electron microscopy (SEM), and wide-angle X ray (WAXS). Glass transition temperature of solvent cast materials, detected by dynamic mechanical analysis (DMA), showed partial molecular interactions between PHBV and PLLA. Crystallinity of the PLLA phase slightly decreased with increasing amount of PHBV, confirming the partial dispersion of PLLA in the PHBV phase. Mechanical properties were analyzed with theoretical models able to predict the behavior of heterogeneous systems. Phase separation was confirmed by SEM observations. © 1994 John Wiley & Sons, Inc.     

Updating of a DRASTIC-based Method for Specific Vulnerability Assessment in Carbonate Aquifers

Abstract

Some methodological modifications are suggested to improve a DRASTIC-based method as a reliable predictor of microbial contamination in extensively fractured and subordinately karstified carbonate aquifers. These modifications will allow a better assessment of vulnerability induced by the concentrated infiltration of surface runoff in two different scenarios: (a) when the karst system is entirely located within an unsaturated aquifer and (b) when the karst system is partially located within a saturated medium. The effectiveness of the updated method has been experimentally verified by comparing the vulnerability values with the results of a hydrogeological and microbiological study at a test site.     

Blinded by anger or feeling the love: How emotions influence advice taking.

Across 2 experiments, the authors demonstrate that emotional states influence how receptive people are to advice. The focus of these experiments is on incidental emotions, emotions triggered by a prior experience that is irrelevant to the current situation. The authors demonstrate that people who feel incidental gratitude are more trusting and more receptive to advice than are people in a neutral emotional state, and people in a neutral state are more trusting and more receptive to advice than are people who feel incidental anger. In these experiments, greater receptivity to advice increased judgment accuracy. People who felt incidental gratitude were more accurate than were people in a neutral state, and people in a neutral state were more accurate than were people who felt incidental anger. The results offer insight into how people use advice, and the authors identify conditions under which leaders, policy makers, and advisors may be particularly influential. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

PYRITE PARTICLE SIZE DISTRIBUTION AND PYRITIC SULFUR REDUCTION IN CRUSHED COALS: A PRELIMINARY REPORT

Six bituminous coals were ground to 28, 100, and 400 mesh x 0, and examined by optical automated image analysis (AIA) to estimate their pyrite particle size distributions and degree of liberation (DOL). These data were used to determine the feasibility of estimating specific-gravity-based pyritic sulfur reduction by AIA methods. Preliminary results indicate that further research is warranted. A review of the progress is presented.