186 research outputs found
Irregular Turbo Codes in Block-Fading Channels
We study irregular binary turbo codes over non-ergodic block-fading channels.
We first propose an extension of channel multiplexers initially designed for
regular turbo codes. We then show that, using these multiplexers, irregular
turbo codes that exhibit a small decoding threshold over the ergodic
Gaussian-noise channel perform very close to the outage probability on
block-fading channels, from both density evolution and finite-length
perspectives.Comment: to be presented at the IEEE International Symposium on Information
Theory, 201
Principios metodológicos para trabajar la didáctica de las matemáticas en los grados de Educación Primaria de la UIC.
Research based on a mathematical program based on six Psychopedagogical principles applying, chosen from a qualitative literature review process and mathematics curriculum of primary education. The paper justifies the application of these principles in order to equip future teachers whith applicable instrument for thought in their work as teachers, help reduce school failure in math and bring this content to everyday life of students.Investigación en base a una programa matemático basado en la aplicación de seis principios psicopedagógicos escogidos a partir de un proceso cualitativo de análisis bibliográfico y curricular de las matemáticas de la Educación Primaria. El artículo justifica la aplicación de estos principios con el objetivo de dotar a los futuros maestros y maestras de instrumentos aplicables y de reflexión para que, en su tarea como docentes, ayuden a disminuir el fracaso escolar en matemáticas y aproximar estos contenidos a la vida cotidiana del alumnado
Els Misteris dels productes de neteja
Embrutar i netejar són dos fenòmens quotidians. Explicar-los, però, no és feina fàcil. En
aquest treball experimental es proposa als alumnes el fet d'investigar d'una manera qualitativa
i mitjançant reaccions senzilles els principals responsables de l'acció netejadora d'alguns
dels productes de neteja més coneguts i fins i tot més televisius.Washing and dirtying are two daily phenomena. Explaining them is not an easy task.
In these laboratory practices, students are encouraged to investigate the main cleaning
products in a qualitative way and by using simple chemical reaction
«Els Elements en capsa»: una taula periòdica real
Tots, en algun moment de la nostra vida, hem hagut d'estudiar la taula periòdica. Què hagués passat si, en lloc de
memoritzar símbols químics, haguéssim pogut manipular-los? En aquest article es presenta com es pot construir
una taula periòdica real i quines aplicacions didàctiques en poden derivar.In some moment of our life, all of us have had to study the periodic table. What would have had happened if
instead of memorizing chemical symbols, we had been able to manipulate them? In this article we show how a real
periodic table can be constructed and which didactic applications can be derived
The Capston Project as a means to improve the quality of assessment within the teaching practice area: A proposal by the Universitat Internacional de Catalunya
[ES] La evaluación de las prácticas educativas sigue, en general, un proceso sistemático que se articula en
torno al eje tutor o tutora de la escuela, tutor o tutora de prácticas de la universidad y autoevaluación
del alumnado. Las percepciones subjetivas, los vínculos personales que se establecen y la imposibilidad
de visualizar de forma continuada cómo el alumnado gestiona su práctica educativa pueden conllevar
algunos sesgos en la objetividad deseada en toda evaluación. Estos sesgos afectarían la calidad de
nuestras evaluaciones. El presente artículo pretende aportar argumentos al valor que puede tener el
Trabajo de Fin de Grado, incluido en el módulo Practicum, como elemento de confirmación de la
competencia educativa personal. Al mismo tiempo se aporta una propuesta de modelo de evaluación de
dicho trabajo, basado en la organización de las tareas que tiene que desarrollar el alumnado, los tutores
y tutoras universitarios y, en este caso, los expertos y expertas constituidos como Tribunal. El referente
de nuestra evaluación viene determinado por las competencias descritas en la normativa propia de la
Facultad de Educación de la Universitat Internacional de Catalunya, reformuladas como resultados de
aprendizaje. En conclusión se pretende adecuar la observación y evaluación de los comportamientos
durante las prácticas a unos indicadores o ítems, lo más específicos posible y contextualizados a las
distintas realidades educativas. Y por lo que respecta al Trabajo de Fin de Grado se pretende utilizar el
mismo sistema, pero centrándonos más en los aspectos profesionalizadores, de espíritu emprendedor,
creatividad y toma de decisiones.[EN] The evaluation of educational practices is, in general, a systematic process that revolves around the axis
tutor school, tutor college practices and students’ self-assessment. The subjective perceptions and the
personal bonds that are established and the inability to visualize in a continuous manner how students
manage their educational practice can lead to some biases in the objectivity required for any evaluation. These biases affect the quality of our assessments. This article attempts to provide arguments to
support the value of the Capstone Project, included in the Practicum module, as a confirmation of the
personal educational competence. At the same time this model provides a proposal for the assessment
of the project, based on the organization of the tasks that students, tutors and university tutors have to
carry out, including, in this case, the members of the Assessment Jury. The benchmark of our evaluation
is set by the competences described in the regulations of the Faculty of Education at the Universitat
Internacional de Catalunya, reformulated as learning outcomes. In conclusion, it aims to adapt the
observation and assessment of the teaching-practice behaviours to a set of indicators or items as specific
as possible and contextualized to different educational realities. And with regard to the Capstone Work
we intend to use the same criteria, but focusing on the professionalizing aspects of entrepreneurial
spirit, creativity and decision making.Fuertes Camacho, MT.; Balaguer Fàbregas, MC. (2012). El TFG como elemento de mejora de la calidad en la evaluación del módulo prácticum: propuesta de la Universitat Internacional de Catalunya (UIC). REDU. Revista de Docencia Universitaria. 10(2):329-343. https://doi.org/10.4995/redu.2012.6111OJS329343102Cid, A.; Zabalza, M.A.; Sanmamed, M.; Raposo, M. y Iglesias, M.L. (Coords.) (2007). Buenas prácticas en el Prácticum. Actas del IX Symposim Internacional sobre Practicum y Prácticas en empresas en la formación universitaria. Pontevedra: Imprenta UniversitariaColl, C.; Palacios, J. y Marchesi, A. (2008). Desarrollo psicológico y educación II. Psicologia de la Educación. Madrid: AlianzaDe Lara, E. y Quintanal, J. (2006). El prácticum en las titulaciones de educación: Reflexiones y experiencias. Madrid: Dykinson S.L.De Miguel Díaz, M., Alfaro Rocher, I., Apodaca Urquijo, P., Arias Blanco, J., García Jiménez, E., Lobato Fraile, C., et al. (2006). Metodologías de enseñanza y aprendizaje para el desarrollo de competencias: Orientaciones para el profesorado universitario ante el espacio europeo de educación superior. Madrid: Alianza Editorial.Huertas, J.A.; Tapia, A.; Trías, D.; Ardura, A. y García, E, (2011). Los escenarios académicos, las identidades de los estudiantes universitarios y el movimiento y cambio de las orientaciones motivacionales entre ellos. En C. Monereo y J.I. Pozo (Eds.) La Identidad en Psicología de la Educación. Madrid: Narcea.MEC (2007). Orden ECI 3854/2007 de 27 de diciembre. Boletín Oficial del Estado. Págs. 53735- 53738MEC (2007a). Orden ECI 3857/2007 de 27 de diciembre. Boletín Oficial del Estado. Págs. 53747- 53750Woolfolk, A.; Hugues, M. y Walkup, V. (2008). Psychology in Education. Essex: Pearso
Assessment of the Impact of Long Integration Time in Geosynchronous SAR Imagery of Agricultural Fields by Means of GB-SAR Data
Geosynchronous Synthetic Aperture Radar (GeoSAR) missions offer the advantage of near-continuous monitoring of specific regions on Earth, making them essential for applications that require continuous information. However, wind induced motion along the inherent long integration time can result in image defocusing, with potential degradation of retrieved information. This paper aims to investigate the impact of GEOSAR long integration time in Synthetic Aperture Radar (SAR) imaging and derived products (time series of backscatter and coherence) required to extract agriculture relevant soil or crop parameters of interest. The study is based on the extensive HydroSoil data acquisition campaign carried out over barley and corn crops, funded by the European Space Agency (ESA). The collected raw data are used to synthesize equivalent apertures with integration times of up to 4 hours, similar to those acquired with a GeoSAR. These Ultra Slow apertures facilitate the assessment of the impact of agricultural scene decorrelation on the generation of images with extended integration times.This work was funded by the European Space Agency (ESA Contract No. 4000132509/20/NL/FF/ab with UPC), supported by the Spanish MCINN funds Unidad de Excelencia Maria de Maeztu MDM-2016-0600 and under projects PID2020-117303GB-C21/AEI/10.13039/501100011033 and PID2020-117303GB-C22/AEI/10.13039/501100011033
Hunting performance of captive-born South China tigers (Panthera tigris amoyensis) on free-ranging prey and implications for their reintroduction
The South China tiger (Panthera tigrisamoyensis), although listed by the IUCNas critically endangered, is probably
extinct in the wild. This leaves captive-born animals as the only stock available for reintroductions. Because
reintroduced tigers will not survive in the wild unless they hunt proficiently, we aimed to determine whether
captive-born tigers were able to hunt free-ranging prey and to evaluate their hunting performance as a criterion
for reintroduction. The effect of other variables on subsequent hunting success, such as the availability of stalking
cover and the upbringing history of tigers while they were cubs were also explored, given their relevance in reintroduction
programs. Twelve tigers over two years of agewere fittedwith GPS collars and placed individually in
100 ha enclosures to determine their kill rate of blesbuck (Damaliscus pygargus), as a measure of their hunting
performance. All tigers but one successfully hunted blesbuck, although kill rate varied substantially amongst individuals,
ranging from one blesbuck every 3.14 days to no blesbuck. Tigers also killed other species indicating
plasticity in their hunting behavior, and showed higher kill rates in the enclosure where cover was more abundant,
confirming the importance of stalking cover in hunting success for this species. Results showed that the
presence of the mother during cub development was not necessary for cubs to hunt later in life, although it
had a positive effect on kill rate. Our study represents the first empirical evidence that captive-born tigers can
successfully hunt free-ranging prey adequately to meet their energetic demands, validating the use of captive animals
to recover wild populations, should other reintroduction criteria be met. Moreover, that tigers adapted to
the African veld ecoregion suggests they should be able to adapt back to southern China where opportunities for
stalking and ambush are more numerous.University of Pretoria.http://www.elsevier.com/locate/bioc2016-12-31hb201
Structure and reactivity of surface oxides on Pt(110) during catalytic CO oxidation
We present the first structure determination by surface x-ray diffraction during the restructuring of a model catalyst under reaction conditions, i.e., at high pressure and high temperature, and correlate the restructuring with a change in catalytic activity. We have analyzed the Pt(110) surface during CO oxidation at pressures up to 0.5 bar and temperatures up to 625 K. Depending on the O2/CO pressure ratio, we find three well-defined structures: namely, (i) the bulk-terminated Pt(110) surface, (ii) a thin, commensurate oxide, and (iii) a thin, incommensurate oxide. The commensurate oxide only appears under reaction conditions, i.e., when both O2 and CO are present and at sufficiently high temperatures. Density functional theory calculations indicate that the commensurate oxide is stabilized by carbonate ions (CO2−3). Both oxides have a substantially higher catalytic activity than the bulk-terminated Pt surface
Neuroanatomical correlates of olfactory loss in normal aged subjects
In non-demented older persons, smell dysfunction, measured premortem, has been associated with postmortem brain degeneration similar to that of Alzheimer's disease. We hypothesized that distinct measures of gray and white matter integrity evaluated through magnetic resonance imaging (MRI) techniques could detect degenerative changes associated with age-related olfactory dysfunction. High-resolution T1-weighted images and diffusion-tensor images (DTI) of 30 clinically healthy subjects aged 51 to 77 were acquired with a 3-Tesla MRI scanner. Odor identification performance was assessed by means of the University of Pennsylvania Smell Identification Test (UPSIT). UPSIT scores correlated with right amygdalar volume and bilateral perirhinal and entorhinal cortices gray matter volume. Olfactory performance also correlated with postcentral gyrus cortical thickness and with fractional anisotropy and mean diffusivity levels in the splenium of the corpus callosum and the superior longitudinal fasciculi. Our results suggest that age-related olfactory loss is accompanied by diffuse degenerative changes that might correspond to the preclinical stages of neurodegenerative processes
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