Search results for "550"
showing 10 items of 1192 documents
A collaborative writing approach to wikis: Design, implementation, and evaluation
2011
Published version of an article from the journal:Issues in Informing Science and Information Technology. Also available from the publisher: http://iisit.org/Vol8/IISITv8p431-449Hadjerrouit224.pdf Wikis provide teachers with potentially significant opportunities for creating socially engaged tasks that require active student participation and collaboration. Wikis allow students to work together to develop content on the web, giving them a sense of how writing can be carried out collaboratively. Collaborative writing offer opportunities not only to practice literature review, academic reading and writing, but also to stimulate reflection, knowledge sharing, and critical thinking. However, des…
Editorial: Special Issue on "5G Workshop on Networks, Services and Applications" : topics from the 1st Joint Workshop between Center for TeleInFrastr…
2010
Published version of an article in Wireless Personal Communications, 57(3), 313-316. Also available from the publisher at http://dx.doi.org/10.1007/s11277-010-0068-7 The first joint workshop between Center for TeleInFrastruktur (CTIF), Denmark and Center for Wireless Innovation (CWI), Norway, was held in Aalborg, Denmark on October 8, 2009, focusing on yet undefined term, "5G mobile networks". This Special Issue features eleven selected papers based on networks, services and applications aspects of 5G.
Developing web-based learning resources in school education: a user-centered approach
2010
Published version of an article from the journal:Interdisciplinary Journal of Knowledge and Learning Objects. Also available from the publisher:http://www.ijello.org/Volume6/IJELLOv6p115-135Hadjerrouit688.pdf Web-based learning resources (WBLRs) are potentially powerful tools for enhancing teachingand learning processes in school education. They can provide teachers and learners with a widerange of new and exciting experiences that are not possible in a traditional classroom. However,WBLRs are still the domain of technical and software experts rather than teachers and learners.As a result, much of the development of WBLRs is carried out without a true understanding ofissues pertinent to lea…
A novel policy-driven reversible anonymisation scheme for XML-based services
2015
Author's version of an article in the journal: Information Systems. Also available from the publisher at: http://dx.doi.org/10.1016/j.is.2014.05.007 This paper proposes a reversible anonymisation scheme for XML messages that supports fine-grained enforcement of XACML-based privacy policies. Reversible anonymisation means that information in XML messages is anonymised, however the information required to reverse the anonymisation is cryptographically protected in the messages. The policy can control access down to octet ranges of individual elements or attributes in XML messages. The reversible anonymisation protocol effectively implements a multi-level privacy and security based approach, s…
Examen de las dinámicas socio-ecológicas en el valle medio del Xuquer (Valencia) desde el Paleolítico Medio hasta el Calcolítico
2017
En paisajes intensamente modificados por terrazas agrícolas y otros usos modernos del suelo, el patrón espacial y temporal del poblamiento prehistórico puede ser difícil de detectar usando métodos de prospección arqueológica tradicionales orientados a la localización de yacimientos part iculares. El abancalamiento del territorio para su explotación agrícola es norma común en el área de trabajo, por lo que es necesario examinar el paisaje en su conjunto, en lugar de intentar localiza r zonas concretas de actividad ant rópica prehistórica. Para superar estos desafíos, se ha empleado una estrategia estratificada, seleccionando aleato ria me nte las parcelas a prospectar, para examinar las diná…
Zvaigžņotā Debess: 2009, Vasara (204)
2009
Contents: E.Conners. The Trojan Asteroids ; V.Šmēlings. Men on the Moon! ; E.Bervalds. Astronomical Domes and “Sauna” ; Z.Alksne, A.Alksnis. Sakurai’s Object Fails to Escape Own Dust ; Z.Alksne, A.Alksnis. R CrB Stars Surrounded by Dust Clouds ; M.Gills. April Started with Astronomy ; A.Alksnis. First Stamps Dedicated to Astronomy by Latvia’s Post-Office ; I.Pundure. Arturs Balklavs and Astronomy of Latvia (till 1969) ; M.Sudārs. Satellite Collisions – What Threat Do They Pose? ; I.Vilks. Dwarf Planets Names in Latvian ; Announcement on the 2nd International Symposium on Dark-sky Parks: 14-19 September 2009, Slovenia ; A.Andžāns. The Best Way to Fight Darkness Is to Switch on Light (Intervi…
Extending the search for neutrino point sources with iceCube above the horizon
2009
Point source searches with the IceCube neutrino telescope have been restricted to one hemisphere, due to the exclusive selection of upward going events as a way of rejecting the atmospheric muon background. We show that the region above the horizon can be included by suppressing the background through energy-sensitive cuts. This approach improves the sensitivity above PeV energies, previously not accessible for declinations of more than a few degrees below the horizon due to the absorption of neutrinos in Earth. We present results based on data collected with 22 strings of IceCube, extending its field of view and energy reach for point source searches. No significant excess above the atmosp…
Enhancements of the refractory submicron aerosol fraction in the Arctic polar vortex: feature or exception ?
2014
In situ measurements with a four-channel stratospheric condensation particle counter (CPC) were conducted at up to 20 km altitude on board the aircraft M-55 Geophysica from Kiruna, Sweden, in January through March (EUPLEX 2003, RECONCILE 2010) and in December (ESSenCe 2011). During all campaigns air masses from the upper stratosphere and mesosphere were subsiding inside the Arctic winter vortex, thus initializing a transport of refractory aerosol into the lower stratosphere (Θ 3 were generally detected. Up to 8 of these 11 particles per cm3 were found to contain thermo-stable (at 250 °C) residuals with diameters of 10 nm to about 1 μm. Particle mixing ratios (150 mg−1) and fractions of non-…
Observation of the suppression of the flux of cosmic rays above 4x10^19eV
2008
The energy spectrum of cosmic rays above 2.5 × 10¹⁸ eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index γ of the particle flux, J ∝ E-γ, at energies between 4 × 10¹⁸ eV and 4 × 10¹⁹ eV is 2.69 ± 0.02(stat) ± 0.06(syst), steepening to 4.2 ± 0.4(stat) ± 0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.
Impact of Manaus City on the Amazon Green Ocean atmosphere: ozone production, precursor sensitivity and aerosol load
2010
As a contribution to the Large-Scale Biosphere-Atmosphere Experiment in Amazonia – Cooperative LBA Airborne Regional Experiment (LBA-CLAIRE-2001) field campaign in the heart of the Amazon Basin, we analyzed the temporal and spatial dynamics of the urban plume of Manaus City during the wet-to-dry season transition period in July 2001. During the flights, we performed vertical stacks of crosswind transects in the urban outflow downwind of Manaus City, measuring a comprehensive set of trace constituents including O<sub>3</sub>, NO, NO<sub>2</sub>, CO, VOC, CO<sub>2</sub>, and H<sub>2</sub>O. Aerosol loads were characterized by concentrations of t…