62 research outputs found

    Cities and energy:urban morphology and residential heat-energy demand

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    Our aim is better understanding of the theoretical heat-energy demand of different types of urban form at a scale of 500 m × 500 m. The empirical basis of this study includes samples of dominant residential building typologies identified for Paris, London, Berlin, and Istanbul. In addition, archetypal idealised samples were created for each type through an analysis of their built form parameters and the removal of unwanted ‘invasive’ morphologies. The digital elevation models of these real and idealised samples were run through a simulation that modelled solar gains and building surface energy losses to estimate heat-energy demand. In addition to investigating the effect of macroscale morphological parameters, microscale design parameters, such as U-values and glazing ratios, as well as climatic effects were analysed. The theoretical results of this study suggest that urban-morphology-induced heat-energy efficiency is significant and can lead to a difference in heat-energy demand of up to a factor of six. Compact and tall building types were found to have the greatest heat-energy efficiency at the neighbourhood scale while detached housing was found to have the lowest

    El modelo de propaganda de Herman y Chomsky: Análisis de prensa sobre la huelga general del 29 de marzo de 2012

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    Este estudio pretende aproximar la visión del modelo de propaganda de Herman y Chomsky al contexto de los medios de comunicación españoles en la actualidad. Para ello es necesario definir la relación existente entre la teoría y el campo de estudio, que serán cuatro diarios generalistas españoles, dos estatales y dos regionales (Comunidad Valenciana). En este sentido, esta parte de la introducción orienta sobre dichos puntos en común para establecer un patrón de análisis. Este análisis se llevará a cabo sobre las noticias publicadas en papel en dichos medios, sin embargo el acceso a los datos relacionados con la publicación de esas noticias (teletipos originales, tratamiento requerido, limitaciones técnicas o estilísticas, etc.) es complicado para un investigador inexperto.Viejo Sánchez, P. (2013). El modelo de propaganda de Herman y Chomsky: Análisis de prensa sobre la huelga general del 29 de marzo de 2012. Universitat Politècnica de València. http://hdl.handle.net/10251/28863Archivo delegad

    Evidence of thermal transport anisotropy in stable glasses of vapour deposited organic molecules

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    Vapour-deposited organic glasses are currently in use in many optoelectronic devices. Their operation temperature is limited by the glass transition temperature of the organic layers and thermal management strategies become increasingly important to improve the lifetime of the device. Here we report the unusual finding that molecular orientation heavily influences heat flow propagation in glassy films of small molecule organic semiconductors. The thermal conductivity of vapour-deposited thin-film semiconductor glasses is anisotropic and controlled by the deposition temperature. We compare our data with extensive molecular dynamics simulations to disentangle the role of density and molecular orientation on heat propagation. Simulations do support the view that thermal transport along the backbone of the organic molecule is strongly preferred with respect to the perpendicular direction. This is due to the anisotropy of the molecular interaction strength that limit the transport of atomic vibrations. This approach could be used in future developments to implement small molecule glassy films in thermoelectric or other organic electronic devices.Comment: main manuscript: 17 pages and 7 figures; supplementary material: 6 pages and 7 figure

    Modeling smart grids as complex systems through the implementation of intelligent hubs

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    ICINCO 2010The electrical system is undergoing a profound change of state, which will lead to what is being called the smart grid. The necessity of a complex system approach to cope with ongoing changes is presented: combining a systemic approach based on complexity science with the classical views of electrical grids is important for an understanding the behavior of the future grid. Key issues like different layers and inter-layer devices, as well as subsystems are discussed and proposed as a base to create an agent-based system model to run simulations

    Using the system dynamics paradigm in teaching and learning technological university subjets

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    2nd International Conference on Education and New Learning TechnologiesKnowledge of Differential Equations is applied to various scientific fields such as physics, chemistry, biology and engineering and therefore often an important part in the basic subjects of mathematics in the first college courses related to those areas. The logic and common sense seems to indicate teachers use these basic skills acquired by students and employ them to curricula development in the following intensification courses, but unfortunately it is not usually the case. According to the authors, that is because instead of using a generic software to set up and solve the problems of Differential Equations that arise at different areas, what we have is a proliferation of software applied to solve special case problems. Some of these programs offer sophisticated graphical user interfaces to create complex system models, usually by putting together some library components, as if it were a puzzle, but without the need to set up the differential equations. According to the authors, this method, although valuable to solve some specific problems very quickly, is aberrant from the educational point of view, because it allows students to solve problems without knowing what they are doing or how they are doing. Worse, if a complication arises in the problem statement, for which there are no pieces in the puzzle, or execution errors occurs due to an incorrect construction, then they are not able solve the problem. Because of this, software that does not hide the equations and with the user can know at any moment what he/she is doing, from the mathematical point of view, is missing. According to the authors, any simulation program including the System Dynamics paradigm meets this condition because its GUI is very close to differential equations and the Initial Value Problem. The modelling of a system using this paradigm is simply to raise because an initial value problem associated with the system is quickly represented by the graphical user interface of the simulation program. This article presents some learning experiences focused on "problem based learning" using AnyLogic, which provides the System Dynamics paradigm to perform simulations of physical systems. The program provides a graphical environment that allows to perform animations very easily. The first on is to simulate the filling of a tank of water where the model is a first order non-linear differential equation. This case is instructive as it is very easy to raise the initial value problem and may be valid to review some concepts already forgotten by the students such as for example the derivative, integral, differential equation and initial value problem. Other simulation exercises posed to students are the control of a cart by a force, a parabolic shooting, and other mechanical, electrical and thermal examples

    Transcranial direct current stimulation in neglect rehabilitation after stroke: a systematic review.

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    Hemispatial neglect is one of the most frequent attention disorders after stroke. The presence of neglect is associated with longer hospital stays, extended rehabilitation periods, and poorer functional recovery. Transcranial direct current stimulation (tDCS) is a new technique with promising results in neglect rehabilitation; therefore, the objective of this systematic review, performed following the PRISMA guidelines, is to evaluate the effectiveness of tDCS on neglect recovery after stroke. The search was done in MEDLINE (PubMed), Web of Science, Scopus, Cochrane Library, and BioMed Central databases. A total of 311 articles were found; only 11 met the inclusion criteria, including 152 post-stroke patients in total. Methodological quality and risk of bias were assessed for all the studies, and methodological characteristics of the studies, sample sizes, methods, main results, and other relevant data were extracted. tDCS intervention ranged from one to twenty sessions distributed in 1 day to 4 weeks, with intensity ranged from 1 to 2 mA. We found moderate evidence for the efficacy of tDCS in the rehabilitation of hemispatial neglect after a stroke, being more effective in combination with other interventions. Nonetheless, the limited number of studies and some studies' design characteristics makes it risky to draw categorical conclusions. Since scientific evidence is still scarce, further research is needed to determine the advantage of this treatment in acute, sub-acute and chronic stroke patients. Future studies should include larger samples, longer follow-ups, and broader neurophysiological assessments, with the final aim of establishing the appropriate use of tDCS as an adjuvant intervention in neurorehabilitation settings.pre-print964 K

    Una concepción moderna de Técnicas de Inteligencia Artificial en la Universidad de Alicante

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    Este trabajo tiene como objetivo presentar la estructura de la asignatura Técnicas de Inteligencia Artificial en la Universidad de Alicante haciendo especial hincapié en los recursos (nuevas tecnologías, material docente y aplicaciones software) empleados durante el desarrollo de la misma. Parte de estos recursos docentes están siendo empleados como herramienta de apoyo para la adaptación al Espacio Europeo de Educación Superior

    Biological differences between in vitro produced bovine embryos and parthenotes

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    Parthenotes may represent an alternate ethical source of stem cells, once biological differences between parthenotes and embryos can be understood. In this study, we analyzed development, trophectoderm (TE) differentiation, apoptosis/necrosis, and ploidy in parthenotes and in vitro produced bovine embryos. Subsequently, using real-time PCR, we analyzed the expression of genes expected to underlie the observed differences at the blastocyst stage. In vitro matured oocytes were either fertilized or activated with ionomycin C6-DMAP and cultured in simple medium. Parthenotes showed enhanced blastocyst development and diploidy and reduced TE cell counts. Apoptotic and necrotic indexes did not vary, but parthenotes evidenced a higher relative proportion of apoptotic cells between inner cell mass and TE. The pluripotence-related POU5F1 and the methylation DNMT3A genes were downregulated in parthenotes. Among pregnancy recognition genes, TP-1 was upregulated in parthenotes, while PGRMC1 and PLAC8 did not change. Expression of p66shc and BAX/BCL2 ratio were higher, and p53 lower, in parthenotes. Among metabolism genes, SLC2A1 was downregulated, while AKR1B1, PTGS2, H6PD, and TXN were upregulated in parthenotes, and SLC2A5 did not differ. Among genes involved in compaction/blastulation, GJA1 was downregulated in parthenotes, but no differences were detected within ATP1A1 and CDH1.Within parthenotes, the expression levels of SLC2A1, TP-1, and H6PD, and possibly AKR1B1, resemble patterns described in female embryos. The pro-apoptotic profile is more pronounced in parthenotes than in embryos, which may differ in their way to channel apoptotic stimuli, through p66shc and p53 respectively, and in their mechanisms to control pluripotency and de novo methylation

    Programación de mundos virtuales: experiencia docente en un curso no reglado

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    Una particularidad de las carreras de Informática es que tratan sobre el estudio de una tecnología en constante cambio y evolución. Los cursos complementarios especiales que ofrecen algunas universidades, permiten a los alumnos acceder a las últimas tecnologías de forma práctica sin necesidad de esperar a un cambio en los planes de estudio. Además, su convalidación por créditos de libre elección les permiten aparecer en el expediente académico oficial del alumno. Presentamos nuestra experiencia en uno de estos cursos, dedicado a la creación de mundos virtuales, indicando su estructura y sus características. Esta experiencia nos ha permitido constatar las ventajas de plantear cursos sobre tecnologías emergentes y el interés que despiertan entre los alumnos, especialmente si, como ocurre en este, se caracterizan por su aplicabilidad y su interactividad
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