584 research outputs found
New Composite Materials in the Technology for Drinking Water Purification from Ionic and Colloidal Pollutants
Multi-axis integrated Hall magnetic sensors
Conventional Hall magnetic sensors respond only to the magnetic field component perpendicular to the surface of the sensor die. Multi-axis sensing capability can be provided in the following two ways: (a) by integrating magnetic flux concentrators on the die, and (b) by using vertical Hall devices. Here we review the most important two-and three-axis integrated Hall magnetic sensors based on these concepts. Their applications include mapping of magnetic fields and sensing angular position
Removal of cationic dye from water by activated pine cones
Adsorption of a cationic phenothyazine dye methylene blueonto activated carbon prepared from pine cones was investigated with the variation in parameters of contact time, dye concentration and pH. The kinetic data were found to follow the pseudo-second-order kinetic modelclosely. The equilibrium data were best represented by the Langmuir isotherm with maximum adsorption capacity of 233.1 mg g-1. Adsorption was favored by using a higher solution pH. Textural analysis by nitrogen adsorption was used to determine specific surface area and pore structure of the obtained carbon. Boehm titrations revealed that carboxylic groups are present in the highest degree on the carbon surface. The results indicate that the presented method for activation of pine cones could yield activated carbon with significant porosity, developed surface reactivity and considerable adsorption affinity toward cationic dye methylene blue
Interpretation and the Constraints on International Courts
This paper argues that methodologies of interpretation do not do what they promise – they do not constrain interpretation by providing neutral steps that one can follow in finding out a meaning of a text – but nevertheless do their constraining work by being part of what can be described as the legal practice
Configurable LDPC Decoder Architecture for Regular and Irregular Codes
Low Density Parity Check (LDPC) codes are one of the best error correcting codes that enable the future generations of wireless devices to achieve higher
data rates with excellent quality of service. This paper presents two novel flexible decoder architectures. The first one supports (3, 6) regular codes of rate 1/2 that can be used for different block lengths. The second decoder is more general and supports both regular and irregular LDPC codes with twelve combinations of code lengths −648, 1296, 1944-bits and code rates-1/2, 2/3, 3/4, 5/6- based on the IEEE 802.11n standard. All codes correspond to a block-structured parity check matrix, in which the sub-blocks are either a shifted identity matrix or a zero matrix. Prototype architectures for both LDPC decoders have been implemented and tested on a Xilinx field programmable gate array.NokiaNational Science Foundatio
Disease Combinations Associated with Physical Activity Identified: The SMILE Cohort Study
In the search of predictors of inadequate physical activity, an investigation was conducted into the association between multimorbidity and physical activity (PA). So far the sum of diseases used as a measure of multimorbidity reveals an inverse association. How specific combinations of chronic diseases are associated with PA remains unclear. The objective of this study is to identify clusters of multimorbidity that are associated with PA. Cross-sectional data of 3,386 patients from the 2003 wave of the Dutch cohort study SMILE were used. Ward's agglomerative hierarchical clustering was executed to establish multimorbidity clusters. Chi-square statistics were used to assess the association between clusters of chronic diseases and PA, measured in compliance with the Dutch PA guideline. The highest rate of PA guideline compliance was found in patients the majority of whom suffer from liver disease, back problems, rheumatoid arthritis, osteoarthritis, and inflammatory joint disease (62.4%). The lowest rate of PA guideline compliance was reported in patients with heart disease, respiratory disease, and diabetes mellitus (55.8%). Within the group of people with multimorbidity, those suffering from heart disease, respiratory disease, and/or diabetes mellitus may constitute a priority population as PA has proven to be effective in the prevention and cure of all three disorders
Synergistic Effects of Six Chronic Disease Pairs on Decreased Physical Activity: The SMILE Cohort Study
Little is known about whether and how two chronic diseases interact with each other in modifying the risk of physical inactivity. The aim of the present study is to identify chronic disease pairs that are associated with compliance or noncompliance with the Dutch PA guideline recommendation and to study whether specific chronic disease pairs indicate an extra effect on top of the effects of the diseases individually. Cross-sectional data from 3,386 participants of cohort study SMILE were used and logistic regression analysis was performed to study the joint effect of the two diseases of each chronic disease pair for compliance with the Dutch PA guideline. For six chronic disease pairs, patients suffering from both diseases belonging to these disease pairs in question show a higher probability of noncompliance to the Dutch PA guideline, compared to what one would expect based on the effects of each of the two diseases alone. These six chronic disease pairs were chronic respiratory disease and severe back problems; migraine and inflammatory joint disease; chronic respiratory disease and severe kidney disease; chronic respiratory disease and inflammatory joint disease; inflammatory joint disease and rheumatoid arthritis; and rheumatoid arthritis and osteoarthritis of the knees, hips, and hands
Modelling and Simulation of Asynchronous Real-Time Systems using Timed Rebeca
In this paper we propose an extension of the Rebeca language that can be used
to model distributed and asynchronous systems with timing constraints. We
provide the formal semantics of the language using Structural Operational
Semantics, and show its expressiveness by means of examples. We developed a
tool for automated translation from timed Rebeca to the Erlang language, which
provides a first implementation of timed Rebeca. We can use the tool to set the
parameters of timed Rebeca models, which represent the environment and
component variables, and use McErlang to run multiple simulations for different
settings. Timed Rebeca restricts the modeller to a pure asynchronous
actor-based paradigm, where the structure of the model represents the service
oriented architecture, while the computational model matches the network
infrastructure. Simulation is shown to be an effective analysis support,
specially where model checking faces almost immediate state explosion in an
asynchronous setting.Comment: In Proceedings FOCLASA 2011, arXiv:1107.584
Degradation of crystal violet over heterogeneous TiO2-based catalysts: The effect of process parameters
In this study, modified sol-gel method was employed to synthesize the pure and Zr-doped titania catalysts. Brunauer-Emmett-Teller (BET) method was applied to determine porosity, X-ray diffraction (XRD) analysis was used to study crystal structure, scanning electron microscopy (SEM) was used to investigate morphology and Fourier transform infrared spectroscopy (FTIR) was used to examine surface properties/total acidity of the obtained catalysts samples. Photocatalytic activity was tested in the reaction of crystal violet (CV) dye decolourization/degradation under UV light irradiation. The effects of several photocatalysis operational parameters were considered, such as catalyst dosage, initial dye concentrations, duration of UV irradiation treatment, as well as catalysts calcination temperatures and dopant amounts. The obtained results indicated faster dye decolourization/degradation with the increase of the catalyst dosage and the decrease of initial CV concentrations. The Zr-doping affects photocatalytic properties, i.e. CV decolourization/degradation of the prepared catalytic materials. Thus, addition of 5 wt.% of ZrO2 to titania increases photocatalytic effect for similar to 15% and addition of 10 wt.% of ZrO2 improves the photocatalytic efficiency of titania for nearly 30%
AR2, a novel automatic muscle artifact reduction software method for ictal EEG interpretation: Validation and comparison of performance with commercially available software.
Objective: To develop a novel software method (AR2) for reducing muscle contamination of ictal scalp electroencephalogram (EEG), and validate this method on the basis of its performance in comparison to a commercially available software method (AR1) to accurately depict seizure-onset location. Methods: A blinded investigation used 23 EEG recordings of seizures from 8 patients. Each recording was uninterpretable with digital filtering because of muscle artifact and processed using AR1 and AR2 and reviewed by 26 EEG specialists. EEG readers assessed seizure-onset time, lateralization, and region, and specified confidence for each determination. The two methods were validated on the basis of the number of readers able to render assignments, confidence, the intra-class correlation (ICC), and agreement with other clinical findings. Results: Among the 23 seizures, two-thirds of the readers were able to delineate seizure-onset time in 10 of 23 using AR1, and 15 of 23 using AR2 (
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