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21.
Dimitris Giakoumis Nikolaos Kaklanis Konstantinos Votis Dimitrios Tzovaras 《Universal Access in the Information Society》2014,13(2):227-248
His paper presents a tool facilitating developers of user interfaces (UIs) to experience accessibility limitations that can be posed from various disabilities during the interaction of impaired users with their developments. In this respect, various aspects of visual, hearing, physical and cognitive impairments have been modelled through filters providing approximate, yet, realistic simulations over them. These filters have formed the basis for the developed tool, which can be used either on its own (as a standalone application), or be embedded in the NetBeans Integrated Development Environment. The tool, named DIAS, allows for impairment simulations to be performed over Java, mobile and web applications. Moreover, it integrates two of the most common assistive technologies (ATs), namely a screen reader and a magnifier. As a result, developers of UIs can not only experience how interaction would be affected from various impairments, but they can also understand how their developments would be perceived by impaired users through an AT. This work aims to provide an integrated, practical solution for impairment simulation, which could be easily adopted by developers, thus realistically increasing the possibilities for the future development of interactive applications that are more accessible to users with disabilities. 相似文献
22.
Nikolaos Dimitratos Jose Antonio Lopez-Sanchez David Morgan Albert Carley Laura Prati Graham J. Hutchings 《Catalysis Today》2007,122(3-4):317-324
Solvent free oxidation of benzyl alcohol was investigated in the absence of a base using Au catalysts prepared by sol immobilization on titania and carbon supports. Comparison between the Au supported catalysts revealed that activity and distribution of products was dependent on the nature of support and heat treatment. Specifically, heat pre-treatment of the Au catalysts has a beneficial effect in terms of activity, but is detrimental in terms of selectivity to the benzaldehyde. We conclude that sol immobilization is a suitable technique for preparing gold catalysts with small particle size and narrow particle size distributions and very high activity and selectivity for benzyl alcohol oxidation. 相似文献
23.
Nikolaos?Nenadis Maria?TsimidouEmail author 《Journal of the American Oil Chemists' Society》2002,79(12):1191-1195
Rapid 1,1-diphenyl-2-picrylhydrazyl (DPPH•) tests are often applied to classify the scavenging activity of phenolic compounds (AH). Published analytical protocols differ
in more than one experimental condition, and results for the relative order or magnitude of activity are often contradictory.
In this work, parameters such as duration of test, [AH]/[DPPH•] molar ratio, and solvent effects were examined and discussed. The test duration and the value of the [AH]/[DPPH•] ratio did not influence the order of activity among tested antioxidants. Ethanol, commonly used as solvent in such tests,
was compared with acetonitrile and tert-butyl alcohol. Solvent properties such as the ability to form hydrogen bonds with the AH seem to influence the level of the
relative activity (%RSA). Higher %RSA values were observed in ethanol. The activity of the most polar compounds was affected
the most, and in some cases (caffeic, dihydrocaffeic, and rosmarinic acids) the order of activity was changed owing to different
kinetics. Standardization of the analytical protocol should include a 20-min reaction period and a molar ratio that permits
attainment of a 60–80% RSA value for the most potent antioxidant. Solvent choice is critical for classifying activity. Safe
classification can be based only on results from kinetic studies. 相似文献
24.
The dynamic swelling behavior of poly(2-hydroxyethyl methacrylate-co-methyl methacrylate) and poly(2-hydroxyethyl methacrylate-co-N-vinyl-2-pyrrolidone) in water was followed at 37°C. The results were analyzed in terms of a simple non-Fickian transport equation, which expresses the fractional penetrant uptake as an exponential function of the diffusion time. The exponent n, which indicates Fickian or non-Fickian transport mechanism, was correlated to the content of the more hydrophilic component of the copolymer. Photomicrographs obtained with polarized light offer new information about the position and movement of the penetrant front in glassy, hydrophilic polymers. 相似文献
25.
Papatheodorou Nikolaos Kouroupetroglou Georgios Pino Alexandros Giannopoulos Panagiotis-Alexios Makris Gerasimos Papageorgiou Charalambos 《Universal Access in the Information Society》2021,20(2):321-331
Universal Access in the Information Society - We present an investigation of the systematic differences in upper limb motor skills between children with learning disabilities (LDs) and children... 相似文献
26.
Nikolaos Petsas Giorgos Kouzilos Giorgos Papapanos Michalis Vardavoulias Angeliki Moutsatsou 《Journal of Thermal Spray Technology》2007,16(2):214-219
The purpose of the present work was the investigation and characterization of the quality of air in a thermal spray industry,
in Greece. The activities that take place in the specific facility, as well as in most other similar industries, include thermal
spraying and several mechanical and metallurgical tasks that generate airborne particles, such as grit-blasting, cutting and
grinding of metallic components. Since the main focus of this work was the workers exposure to airborne particles and heavy
metals, portable air samplers with quartz fiber filters, were used daily for 8 h. Three samplers, carried from different employees,
were used for a period of 1 month. Results showed that both particles and heavy metals concentrations were low, even in the
production site, which was the most susceptible area. The only exceptions were observed in the case of cleaning and maintenance
activities in the thermal spray booth and in the case of spraying outside the booth. The main reason for the low concentrations
is the fact that most of the activities that could produce high-particle concentrations are conducted in closed, well-ventilated
systems. Statistical elaboration of results showed that particles are correlated with Ni, Cu, Co. The same conclusion is extracted
for Fe, Mn. These correlations indicate possible common sources. 相似文献
27.
28.
Konstantinos Makantasis Eftychios Protopapadakis Anastasios Doulamis Nikolaos Doulamis Nikolaos Matsatsinis 《Multimedia Tools and Applications》2016,75(22):15017-15049
Falls have been reported as the leading cause of injury-related visits to emergency departments and the primary etiology of accidental deaths in elderly. Thus, the development of robust home surveillance systems is of great importance. In this article, such a system is presented, which tries to address the fall detection problem through visual cues. The proposed methodology utilizes a fast, real-time background subtraction algorithm, based on motion information in the scene and pixels intensity, capable to operate properly in dynamically changing visual conditions, in order to detect the foreground object. At the same time, it exploits 3D space’s measures, through automatic camera calibration, to increase the robustness of fall detection algorithm which is based on semi-supervised learning approach. The above system uses a single monocular camera and is characterized by minimal computational cost and memory requirements that make it suitable for real-time large scale implementations. 相似文献
29.
Nikolaos Gianniotis Christoph Schnörr Christian Molkenthin Sanjay Singh Bora 《Pattern Analysis & Applications》2016,19(2):475-485
Variational methods are employed in situations where exact Bayesian inference becomes intractable due to the difficulty in performing certain integrals. Typically, variational methods postulate a tractable posterior and formulate a lower bound on the desired integral to be approximated, e.g. marginal likelihood. The lower bound is then optimised with respect to its free parameters, the so-called variational parameters. However, this is not always possible as for certain integrals it is very challenging (or tedious) to come up with a suitable lower bound. Here, we propose a simple scheme that overcomes some of the awkward cases where the usual variational treatment becomes difficult. The scheme relies on a rewriting of the lower bound on the model log-likelihood. We demonstrate the proposed scheme on a number of synthetic and real examples, as well as on a real geophysical model for which the standard variational approaches are inapplicable. 相似文献
30.