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61.
Markel Vigo Amaia Aizpurua Myriam Arrue Julio Abascal 《Universal Access in the Information Society》2011,10(1):33-49
Conformance metrics for the mobile web can play a crucial role as far as engineering mobile websites are concerned, especially
if they are automatically obtained. In this way, developers can have an idea in numeric terms of how suitable their developments
are for mobile devices. However, there are a plethora of devices with their own particular features (screen size, formats
support, etc.) that restrict a unified automatic assessment process. This paper proposes a tool-supported method for device-tailored
assessment in terms of conformance with Mobile Web Best Practices 1.0, including the definition of five quantitative metrics
for automatically measuring mobile web conformance: Navigability, Page layout, Page definition, User input and Overall score.
The behaviour of these metrics was analysed for different devices and different web paradigms, both mobile web pages and their
equivalent desktop pages. As expected, the results show that mobile web pages on more capable devices score higher. In addition,
20 users took part in an experiment aimed at discovering how conformance-based scores relate to usability dimensions. The
results demonstrate that automatic scoring approaches strongly correlate with usability scores obtained by direct observation,
such as task completion time and user satisfaction. This correlation is even stronger for the device-tailored assessment than
the one that assumes a general profile for all devices. For instance, results show a strong negative correlation between Overall
score and task completion time: ρ (9) = −0.81, (p < 0.05) for the generalist approach and ρ (9) = −0.88 for the device-tailored one, entailing that mobile web guidelines and
the metrics based on their conformance capture usability aspects. This result challenges the widely accepted belief that conformance
to guidelines does not imply more usable web pages, at least for web accessibility conformance. 相似文献
62.
Amaia Igartua Xana Fernández Rolf Luther Jürgen Rausch Michael Berg Benjamin Duffau Mathias Woydt 《Tribology International》2009,42(4):561-568
The research institution TEKNIKER has coordinated the EUROPEAN Project EREBIO, were different biodegradable lubricants have been formulated by FUCHS and BAM for heavy duty engines (GUASCOR), and passenger cars (RENAULT). In the frame of this article, it has been summarised the results obtained when developing biodegradable passenger car lubricants in combination with triboreactive materials.Replacing hydrocarbon-based oils with biodegradable products is one of the ways to reduce adverse effects on the ecosystem caused by the use of lubricants. The application of low or no sulphur, ash and phosphorous (lowSAP) ester- or polyglycol-based oils, intended for passenger car engine lubricants as substitutes for hydrocarbon-based oils, required the preparation of a composition of lubricants with comparable tribological and functional properties.The study is focussed on passenger car motor oils (PCMO) with reduced metal-organic additives. This is necessary in order to reduce the ash build-up in the after treatment system and therefore improve its efficiency and lifetime. High fuel efficiency and long drain intervals are requested, as well. To follow a line in a consequent way, these oils have to be biodegradable and non-toxic to the aqueous environment according to the directive EC/1999/45, coherent with other international standard. In a modern diesel or gasoline engine, the engine oils has to fulfil quite a number of different functions, such as lubricating and cooling the system, wear protection, soot and particle handling with less deposit tendency and so on.In the paper a study of the biodegradability, toxicity and the tribological properties has been carried out for new developed prototype engine bio-oils. Also, some different plasma sprayed triboreactive coatings have been deposited on cast iron piston rings, being studied also their tribological properties. Finally, the behaviour of the new bio-oils selected and plasma sprayed triboreactive coatings on piston rings have been screened in a real engine. 相似文献
63.
González-Salgado A González-Jaén T Vázquez C Patiño B 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2008,25(6):758-764
Aspergillus flavus is frequently found in food, producing a wide variety of toxins, aflatoxins being the most relevant in food safety. A specific PCR-based protocol for this species is described which allowed discrimination from other closely related species having different profiles of secondary metabolites from the Aspergillus Section Flavi, particularly A. parasiticus. The specific primers were designed on the multi-copy internal transcribed region of the rDNA unit (ITS1-5.8S-ITS2 rDNA) and were tested in a wide sample of related species and other fungal species commonly found in food. The PCR assay was coupled with a fungal enrichment and a DNA extraction method for wheat flour to enhance the sensitivity of the diagnostic protocol. The results indicated that the critical PCR amplification product was clearly observed for wheat flour contaminated by 10(2) spores after 16 h of incubation. 相似文献
64.
Forecasting Weekly Evapotranspiration with ARIMA and Artificial Neural Network Models 总被引:6,自引:0,他引:6
Gorka Landeras Amaia Ortiz-Barredo José Javier López 《Canadian Metallurgical Quarterly》2009,135(3):323-334
Information about the parameters defining water resources availability is a key factor in their management. Reference evapotranspiration (ET0) prediction is fundamental in planning, design, and management of water resource systems for irrigation. The application of time series analysis methodologies, which allow evapotranspiration prediction, is of great use for the latter. The objective of the present study was the comparison of weekly evapotranspiration ARIMA and artificial neural network (ANN)-based forecasts with regard to a model based on weekly averages, in the region of álava situated in the Basque Country (northern Spain). The application of both ARIMA and ANN models improved the performance of 1?week in advance weekly evapotranspiration predictions compared to the model based on means (mean year model). The ARIMA and ANN models reduced the prediction root mean square differences with respect to the mean year model (based on historical averages) by 6–8%, and reduced the standard deviation differences by 9–16%. The variations in the performances of the prediction models evaluated depended on the weekly evapotranspiration patterns of the different months. 相似文献
65.
Additive manufacturing (AM) technologies are currently employed for the manufacturing of completely functional parts and have gained the attention of high-technology industries such as the aerospace, automotive, and biomedical fields. This is mainly due to their advantages in terms of low material waste and high productivity, particularly owing to the flexibility in the geometries that can be generated. In the tooling industry, specifically the manufacturing of dies and molds, AM technologies enable the generation of complex shapes, internal cooling channels, the repair of damaged dies and molds, and an improved performance of dies and molds employing multiple AM materials. In the present paper, a review of AM processes and materials applied in the tooling industry for the generation of dies and molds is addressed. AM technologies used for tooling applications and the characteristics of the materials employed in this industry are first presented. In addition, the most relevant state-of-the-art approaches are analyzed with respect to the process parameters and microstructural and mechanical properties in the processing of high-performance tooling materials used in AM processes. Concretely, studies on the AM of ferrous (maraging steels and H13 steel alloy) and non-ferrous (stellite alloys and WC alloys) tooling alloys are also analyzed.The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-021-00365-y 相似文献
66.
Pedro Egizabal Maider García de Cortázar Amaia Torregaray Amélie Veillère Joël Douin Jean‐François Silvain 《Advanced Engineering Materials》2011,13(9):887-894
Two aluminium alloys with 6 wt% TiB2 particles are studied for applications where increased wear resistance and mechanical strength at high temperature are required. The incorporation of hard ceramic particles has a strong influence on the microstructure and properties of the alloys. TiB2 particles play an important role in the nucleation of the different phases of the alloys during solidification, and in the reduction of grain size and porosity. The solidification patterns of Al‐Si7Mg0.3 + TiB2 (6 wt%) and Al‐Cu5MgTi + TiB2 (6 wt%) materials are compared to their corresponding non‐reinforced alloys, and the microstructures are analyzed. 相似文献
67.
Solar Cells: High‐Entropy Mixtures of Pristine Fullerenes for Solution‐Processed Transistors and Solar Cells (Adv. Mater. 45/2015)
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68.
Characterization of poly (N‐vinyl formamide) by size exclusion chromatography–multiangle light scattering and asymmetric‐flow field‐flow fractionation–multiangle light scattering
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Julieta Zataray Amaia Agirre Paula Carretero Leire Meabe José C. de la Cal Jose R. Leiza 《应用聚合物科学杂志》2015,132(34)
The molar mass and the radius of gyration of three poly N‐vinyl formamide (polyNVF) synthesized in aqueous solution polymerization were characterized using two different fractionation techniques: size exclusion chromatography (SEC) and asymmetric‐flow field‐flow fractionation (AF4) coupled with a multiangle light scattering (MALS) and a refractive index (RI) detector. For the sake of comparison, the polymers were also characterized by MALS using the Zimm plot approach (no fractionation). The dn dc?1 of the poly (N‐vinyl formamide) was measured (0.1564 mL g?1) and it was found to be insensitive to the molar mass (in the range 150–450 kDa) and also to the eluents used (DDI water or mixed eluent DDI water/acetonitrile (80 : 20) at pH = 5.5). Interestingly, the concentrations of the samples injected in the SEC and AF4 should be different because concentrations in the range of 20–40 mg mL?1 used for the AF4 caused overloading and anomalous elution in the SEC and hence misleading molar masses. At adequate concentrations in each fractionation equipment, the molar masses were in reasonable good agreement although AF4/MALS provided larger values than the other two techniques likely because samples were not filtered before injection. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42434. 相似文献
69.
The inactivation and photoreactivation response of six seafood-isolated Listeria monocytogenes and one Listeria innocua strain after pulsed light (PL) treatment was evaluated. The lower inactivation levels found after exposure of treated samples to daylight during the first 90 min of storage confirmed that both L. innocua and L. monocytogenes have the capability to photorepair PL-induced DNA damage upon appropriate conditions. Photoreactivation levels from 0.2 to 2.1 log CFU cm?2 were observed depending on treatment intensity (fluence) and Listeria strain. Complete photorepair of PL-caused damage was not found even after treatments inducing low inactivation levels. Photoreactivation increased up to 2.1 log with the applied fluence up to a threshold able to cause between 2.4 and 5.4 log reductions under dark storage. Photorepair was not avoided but lower photoreactivation was observed after higher fluence inducing more than 6 log reductions under dark storage. Both L. innocua and L. monocytogenes serotype 1/2b exhibited the highest photoreactivation levels whereas serotypes 1/2a showed the lowest ones. The overall inactivation and photoreactivation responses of tested Listeria strains were comparable indicating that L. innocua may be a good surrogate for the safe evaluation, optimization and validation of PL technology to control L. monocytogenes in food products and food processing facilities. 相似文献
70.
Increased Small Intestine Expression of Non‐Heme Iron Transporters in Morbidly Obese Patients With Newly Diagnosed Type 2 Diabetes
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