Exploiting symmetries in skyrmionic micromagnetic simulations : cylindrical and radial meshes

Altres ajuts: Acord transformatiu CRUE-CSICMicromagnetic simulations are an essential tool in the theoretical study of magnetic skyrmions. When confined into nanometric samples, these structures can serve as bits of information among other possible applications. Accurate simulations are one of the major sources of theoretical results. In the case of confined skyrmions, it is known that the boundaries play a critical role in their stabilization. However, most of the micromagnetic simulations are done using a finite-difference method with quadrilateral meshes, that do not exactly fit the boundaries. The use of this mesh can introduce a significant numerical error that can completely change the results of the simulations. We present here two different finite-difference meshes to study skyrmions in confined disks, taking advantage of the symmetry of that geometry. A two-dimensional cylindrical mesh for non-symmetric scenarios but geometrically symmetric (boundary conditions) that reduces the propagation of the numerical error, and the particular case of a one dimensional mesh for axisymmetric scenarios where the computation time is hugely reduced

Public Perception of Urban Air Quality Using Volunteered Geographic Information Services

Investigating perceived air quality (AQ) in urban areas is a rather new topic of interest. Papers presenting results from studies on perception of AQ have thus far focused on the individual characteristics leading to a certain AQ perception or have compared personal perception with on-site measurements. Here we present a novel approach, namely applying volunteered geographic information (VGI) technologies in urban AQ monitoring. We present two smartphone applications that have been developed and applied in two EU projects (FP7 CITI-SENSE and H2020 hackAIR) to obtain citizens’ perception of AQ. We focus on observations reported through the smartphone apps for the greater Oslo area in Norway. In order to evaluate whether the reports on perceived AQ contain information about the actual spatial patterns of AQ, we carried out a comparison of the perception data against the output from the high-resolution urban AQ model EPISODE. The results indicate an association between modelled annual average pollutant concentrations and the provided perception reports. This demonstrates that the spatial patterns of perceived AQ are not entirely random but follow to some extent what would be expected due to proximity of emission sources and transport. This information shows that VGI about citizens’ perception of AQ has the potential to identify areas with low environmental quality for urban development

Critical Issues and Lessons Learned in Establishing Concurrent International MS Degree Programs in Engineering Technology

Globalization, competitiveness, and innovation are frequently employed themes as governments, business and industry and universities attempt to respond to the challenges facing them. Clearly business as usual is not likely to be successful in the future. One strategic response for universities has been a significant impetus – in many parts of the world – towards dual, joint or concurrent degree programs involving international partners. It is perhaps not surprising that engineering is among the disciplines that make most use of international collaboration but it seems that engineering technology programs do not yet participate as extensively in this aspect of international education. Furthermore, it seems that much of the movement towards such collaborative degrees is occurring at the Master’s level

Concurrent Masters Degrees Across the Atlantic: Innovations, Issues and Insights

Atransatlantic degree consortium to implement a four-semester dual masters degree initiative across a three-institution consortium consisting of Purdue University (USA), the Technological University Dublin (DIT), and the Universitat Politècnica de Catalunya (Spain) is presented in this paper

Mobile technologies and personalized environmental information for supporting sustainable mobility in Oslo: The citisense-mob approach

Abstract Urban and peri-urban growth is increasing world-wide and Europe is now one of the most urbanized continents in the world. Oslo is one of the fastest growing cities in Europe. This creates pressure on its infrastructure, including traffic and environmental urban quality. Additionally, vehicular traffic is a major contributor to CO 2 emissions, which impacts climate change. It is recognized that air quality is a major factor for human health however, although different measures have been implemented, improving air quality and lowering carbon emissions still remains an unsolved problem in Oslo. The main objective of Citi-Sense-MOB is to demonstrate how using innovative technology to continuously measure environmental data at the road level combined with innovative Information and Communication Technologies (ICT) can help to create a dynamic city infrastructure for realtime city management, access to personalized environmental information and sustainable development. The output from the project will be mobile services for citizens and authorities based on the use of near real-time data on air quality and CO 2 emissions at road level. The societal importance of these services arises from a need to mitigate the effects of air pollution and climate change, and to combat respiratory diseases related to traffic-related air pollution. In order to motivate citizens to use the information generated by the project, Citi-Sense-MOB will provide them with personalized environmental information, as for instance alerting systems when pollution levels exceed a critical threshold. Customized information will also be provided to authorities consisting of detailed air quality maps at high spatial resolution and an evaluation of possibilities to reduce CO 2 emissions by improving driving practices in public urban fleets

The valve uptake index : improving assessment of prosthetic valve endocarditis and updating [ 18 F]FDG PET/CT(A) imaging criteria

Diagnosis of prosthetic valve endocarditis (PVE) by positron emission computed tomography angiography (PET/CTA) is based on visual and quantitative morpho-metabolic features. However, the fluorodeoxyglucose (FDG) uptake pattern can be sometimes visually unclear and susceptible to subjectivity. This study aimed to validate a new parameter, the valve uptake index [VUI, maximum standardized uptake value (SUVmax)−mean standardized uptake value (SUVmean)/SUVmax], designed to provide a more objective indication of the distribution of metabolic activity. Secondly, to re-evaluate the utility of traditionally used PVE imaging criteria and determine the potential value of adding the VUI in the diagnostic algorithm of PVE. Retrospective analysis of 122 patients (135 prosthetic valves) admitted for suspicion of endocarditis, with a conclusive diagnosis of definite (N = 57) or rejected (N = 65) PVE, and who had undergone a cardiac PET/CTA scan as part of the diagnostic evaluation. We measured the VUI and recorded the SUVmax, SUVratio, uptake pattern, and the presence of endocarditis-related anatomic lesions. The VUI, SUVmax, and SUVratio values were 0.54 ± 0.1 vs. 0.36 ± 0.08, 7.68 ± 3.07 vs. 3.72 ± 1.11, and 4.28 ± 1.93 vs. 2.16 ± 0.95 in the 'definite' PVE group vs. the 'rejected' group, respectively (mean ± SD; P 0.45 showed a sensitivity, specificity, and diagnostic accuracy for PVE of 85%, 88%, and 86.7% and increased diagnostic ability for confirming endocarditis when combined with the standard diagnostic criteria. The VUI demonstrated good diagnostic accuracy for PVE, even increasing the diagnostic power of the traditionally used morphometabolic parameters, which also confirmed their own diagnostic performance. More research is needed to assess whether the integration of the VUI into the PVE diagnostic algorithm may clarify doubtful cases and thus improve the diagnostic yield of PET/CTA

Modeling PM10 Originating from Dust Intrusions in the Southern Iberian Peninsula Using HYSPLIT

The Hybrid Single-Particle Lagrangian Integrated Trajectories (HYSPLIT) model has been applied to calculate the spatial and temporal distributions of dust originating from North Africa. The model has been configured to forecast hourly particulate matter#10 mm(PM10) dust concentrations focusing on the impacts over the southern Iberian Peninsula. Two full years (2008 and 2009) have been simulated and compared against surface background measurement sites. A statistical analysis using discrete and categorical evaluations is presented. The model is capable of simulating the occurrence of Saharan dust episodes as observed at the measurement stations and captures the generally higher levels observed in eastern Andalusia, Spain, with respect to the western Andalusia station. But the simulation tends to underpredict the magnitude of the dust concentration peaks. The model has also been qualitatively compared with satellite data, showing generally good agreement in the spatial distribution of the dust column