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101.
Claudia Loitsch Gerhard Weber Nikolaos Kaklanis Konstantinos Votis Dimitrios Tzovaras 《User Modeling and User-Adapted Interaction》2017,27(3-5):445-491
Moving between devices is omnipresent, but not for people with disabilities or those who require specific accessibility options. Setting up assistive technologies or finding settings to overcome a certain barrier can be a demanding task for people without technical skills. Context-sensitive adaptive user interfaces are advancing, although migrating access features from one device to another is very rarely addressed. In this paper, we describe the knowledge-based component of the Global Public Inclusive Infrastructure that infers how a device shall be best configured at the operating system layer, the application layer and the web layer to meet the requirements of a user including possible special needs or disabilities. In this regard, a mechanism to detect and resolve conflicting accessibility policies as well as recommending preference substitutes is a main requirement, as elaborated in this paper. As the proposed system emulates decision-making of accessibility experts, we validated the automatic deduced configurations against manual configurations of ten accessibility experts. The assessment result shows that the average matching score of the developed system is high. Thus, the proposed system can be considered capable of making precise decisions towards personalizing user interfaces based on user needs and preferences. 相似文献
102.
Thermal and reduction-oxidation stability of substituted LaMn1−yCoyO3 perovskite-type oxides (0.0 ≤ yCo ≤ 1.0) prepared by the citrate route have been studied by means of surface area, X-ray diffraction, FTIR spectroscopy and magnetic properties. The perovskite orthorhombic structure is found for yCo ≤ 0.5, with the exception of yCo = 0.1, which corresponds better to rhombohedral LaMnO3.15. For yCo > 0.5 the diffraction profiles are quite similar to the cobaltite’s rhombohedral structure. Magnetic iso-field studies (ZFC-FC) reveal that, for yCo ≤ 0.50, the system presents an antiferromagnetic canted-like ordering of the Mn/Co sublattice, in which the presence of divalent Co ion creates Mn3+-Mn4+ pairs that interact ferromagnetically through the oxygen orbital. This interpretation is confirmed by the magnetization loops, in which the magnetic moment increases when substituting Mn for Co. Therefore, the general trend is: for yCo ≤ 0.5, the Co ions are inserted in the manganite structure and for yCo > 0.5, the Mn ions are inserted in cobaltite structure. The enhancement of the ferromagnetic properties and the thermal stability against reduction for yCo = 0.5 is attributed to optimized Co2+-Mn4+ interactions. 相似文献
103.
Sara Morandi Claudia Focardi Mila Nocentini Marta Puggelli Gabriella Caminati 《Food Analytical Methods》2009,2(4):271-281
The development of a fast and reliable screening method for the determination of tetracycline residues in milk is described
and compared to high-performance liquid chromatography. The method is based on europium-sensitized luminescence: The emissive
properties of the lanthanide cation are used as a fingerprint of europium (III) complexation with tetracycline. The optimization
of the extraction and purification procedures provided a simple and convenient route to prepare stable tetracycline samples
that can safely resist freezing cycles. The method is validated for the first time in milk matrix: The results show that accuracy
and precision of the method meet complaints with the criteria of the Commission Decision 2002/657/EC. The proposed method
has a false compliant rate (β error) lower than 5%. 相似文献
104.
105.
Cristiana Bragalli Claudia D’Ambrosio Jon Lee Andrea Lodi Paolo Toth 《Optimization and Engineering》2012,13(2):219-246
We propose a practical solution method for real-world instances of a water-network optimization problem with fixed topology using a nonconvex continuous NLP (NonLinear Programming) relaxation and a MINLP (Mixed Integer NonLinear Programming) search. Our approach employs a relatively simple and accurate model that pays some attention to the requirements of the solvers that we employ. Our view is that in doing so, with the goal of calculating only good feasible solutions, complicated algorithmics can be confined to the MINLP solver. We report successful computational experience using available open-source MINLP software on problems from the literature and on difficult real-world instances. An important contribution of this paper is that the solutions obtained, besides being low cost, are immediately usable in practice because they are characterized by an allocation of diameters to pipes that leads to a correct hydraulic operation of the network. This is not the case for most of the other methods presented in the literature. 相似文献
106.
Photo‐crosslinking of poly[ethene‐stat‐(methacrylic acid)] functionalised with maleimide side groups
Nadine Schmeling Katharina Hunger Gernot Engler Benjamin Breiten Patrick Rölling Alexander Mixa Claudia Staudt Karl Kleinermanns 《Polymer International》2009,58(7):720-727
BACKGROUND: Photo‐crosslinkable polymers are well known and commercially applied as photoresists. But so far they have not been applied as membrane materials for separation processes. They would offer certain advantages in membrane fabrication over conventional crosslinked polymer materials. Therefore, in this work, a poly[ethene‐stat‐(methacrylic acid)] (PEMAA) which is a potential membrane polymer for different separation problems was functionalised with photo‐crosslinkable maleimide side groups. RESULTS: It has been shown that PEMAA can be used as basic polymer material and a conversion with 3‐hydroxypropylmaleimide is possible in order to obtain a photo‐crosslinkable polymer. Investigation of the crosslinking mechanism was performed using stationary infrared and UV‐visible spectroscopy as well as nanosecond transient spectroscopy absorption measurements of a rotating film. Intense transient absorption of the maleimide‐esterified PEMAA occurs at 250 nm in the film pointing to maleimide anion formation and crosslinking via an ionic dimerisation mechanism. CONCLUSION: It is found that crosslinking reactions can be observed spectroscopically in situ using a maleimide‐functionalised PEMAA. Furthermore, experiments can be performed in the liquid phase (polymer in solution) as well as in the solid phase (polymer film) using a rotating polymer film sample. Maleimide anion formation and crosslinking via an ionic dimerisation mechanism can be investigated by variation of the polymer structure as well as the structure of the maleimide side groups. Copyright © 2009 Society of Chemical Industry 相似文献
107.
Neidert Pamela L.; Dozier Claudia L.; Iwata Brian A.; Hafen Megan 《Canadian Metallurgical Quarterly》2010,7(2):103
Individuals with intellectual and developmental disabilities (IDD) have deficits in adaptive behavior, slow rates of learning, and behavior disorders that interfere with learning or place them or others at risk. Since the 1960s, researchers and clinicians in the field of applied behavior analysis have used methods based on principles of learning to increase adaptive behavior and decrease the occurrence of behavior disorders of individuals with IDD. This article provides an overview of assessment and treatment strategies used in behavior analysis to effect positive changes in the quality of life for individuals with IDD and presents an illustrative case study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
When working in safety critical environments, such as railway signalling, technologies are often used to assist the operator in order to make safe decisions as well as to increase efficiency. Keeping mental workload at manageable levels is one of the most critical factors to ensure that tasks can be completed in a safe and effective manner. Numerous methods have been used to measure mental workload, but none of these have managed to show the use of distinct resource pools. This paper therefore measures the levels of usage of different cognitive processes when typical tasks are carried out in two railway signalling environments. To that end, the Multiple Resource Questionnaire is used. The aims of this paper are twofold: First, it establishes the value of the Multiple Resource Questionnaire as a technique in human factors. Second, it investigates and compares the cognitive resources required to carry out the railway signalling task in two different signalling environments. 相似文献
109.
110.
Gelatin nanoparticles produced by a simple W/O emulsion as delivery system for methotrexate 总被引:3,自引:0,他引:3
Cascone MG Lazzeri L Carmignani C Zhu Z 《Journal of materials science. Materials in medicine》2002,13(5):523-526
Biodegradable hydrophilic gelatin nanoparticles, containing different initial amounts of methotrexate (MTX), were prepared using a simple solvent evaporation technique based on a single water-in-oil emulsion and stabilized by the use of glutaraldehyde as cross-linking agent. The effects of several parameters on particle size, drug encapsulation efficiency and drug release were investigated. Size and shape of the nanoparticles were examined by scanning electron microscopy. The release of MTX was monitored in vitro and the mechanism of release was studied. Particles with a mean diameter of 100–200 nm were produced, which were able to release MTX following a diffusion-controlled mechanism of release. It was observed that the initial amount of MTX used for sample loading did not have any effect on the pattern of release, while it affected the amount of drug entrapped into the nanoparticles and also both the release rate and the total amount of drug released. 相似文献