4,090 research outputs found
Un modelo pragmático de la comunicación escrita en el aula de ciencias
En este artículo presentamos un modelo pragmático aproximado de la comunicación escrita en el aula de ciencias. Nos hemos basado eminentemente en las ideas de Umberto Eco sobre la interpretación de textos. Hemos denominado a este modelo aproximación interpretativa (ApIn). El modelo ApIn nos lleva a una nueva visión de la realidad de aula, que trae consigo una reinterpretación de muchos aspectos didácticos y, muy en especial, de la evaluación del aprendizaje. A su vez, el enfoque pragmático permite estudiar de una manera original el problema de la relación entre lenguaje científico y lenguaje ordinario en la enseñanza de las ciencias.In this paper, we present an approximated pragmatic model of written communication in the science classroom. It is mainly based on Umberto Eco's ideas on text interpretation. We have called this model Interpretative Approximation (ApIn, for the Spanish, aproximación interpretativa). The ApIn model brings about a re-interpretation of many didactic features and, in particular, of didactic assessment. Besides, this pragmatic approach allows a fresh view on the problem of the relationship between scientific and ordinary language in the framework of science teaching
Teucrium x motae nothosp. nov. para el SE Ibérico
Con motivo de las recolecciones que
uno de los autores viene realizando en la
mitad oriental de la provincia de Almería, se
ha encontrado un nuevo híbrido del género
Teucrium cuyos progenitores corresponden a
Teucrium carolipaui subsp. fontqueri (Sennen
Dos novedades corológicas importantes de orquídeas raras en el sureste ibérico
Two important chorological novelties of rare orchids in the south-east of the Iberian PeninsulaPalabras clave. Corología, sureste de España, orquídeas, Aceras anthropophorum, Epipactis microphylla.Key words. Geographical distribution, south-east of Spain, orchids, Aceras anthropophorum, Epipactis microphylla
An experimental strategy for characterizing inductive electromagnetic energy harvesters
Condition monitoring of high voltage power lines through self-powered sensor systems has become a priority for utilities with the aim of detecting potential problems, enhancing reliabilityof the power transmission and distribution networks and mitigating the adverse impact of faults. Energy harvesting from the magnetic field generated by the alternating current flowing through highvoltage lines can supply the monitoring systems with the required power to operate without relying onhard-wiring or battery-based approaches. However, developing an energy harvester, which scavengesthe power from such a limited source of energy, requires detailed design considerations, which maynot result in a technically and economically optimal solution. This paper presents an innovativesimulation-based strategy to characterize an inductive electromagnetic energy harvester and the power conditioning system. Performance requirements in terms of the harvested power and output voltage range, or level of magnetic core saturation can be imposed. Different harvester configurations, whichsatisfy the requirements, have been produced by the simulation models. The accuracy and efficiency ofthis approach is verified with an experimental setup based on an energy harvester, which consists ofa Si-steel magnetic core and a power conditioning unit. For the worst-case scenario with a primary current of 5 A, the maximum power extracted by the harvester can be as close as 165 mW, resulting ina power density of 2.79 mW/cm3.Comunidad de MadridAgencia Estatal de Investigació
Utilización de criterios bioclimáticos y florísticos en la subdivisión biogeográfica del sector subbético (provincia Bética)
Utilización de criterios bioclimáticos yflorísticos en la subdivisión biogeo gráfica del sector subbético (provincia bética, España). Se han estudiado los distintos subsectores reconocidos hasta el momento del sector Subbético: Subbético-Maginense, Cazorlense, Alcaracense y Subbético-Murciano. Atendiendo al régimen de precipitaciones, se han observado diferencias significativas tanto en las precipitaciones anuales, como en su distribución estacional. En los tres primeros subsectores predominan las de carácter invernal; en el Subbético-Murciano las primaverales-otoñales, con mayor incidencia de las de verano. Asimismo, se han analizado los taxones característicos de cada subsector. Del análisis del conjunto de los datos, se ha detectado una gran afinidad entre los subsectores Cazorlense y Alcaracense considerando este último una variante fría del anterior, por lo que se propone la fusión de ambos en un nuevo subsector Alcaracino-Cazorlense. El subsector Subbético-Maginense, con un alto grado de singularidad, presenta mayor influencia de los sectores béticos colindantes. El subsector Subbético-Murciano engloba los territorios más continentales y de mayor influencia iberolevantina
Comparison on the durability of different portland cements after five years exposure to sulfate and to sea water attack
Experimental research has been performed to relate specific cement characteristics to deterioration due to sulfate and sea water attack after five year exposure, and to study different test method suitability for sulfate and marine resistance. Sulfate resistance testing have been performed on mortar specimens made with fifteen cement types of statistically diverse chemical composition according to European standard EN 197-1, most of them with sulfate resistant properties according to Spanish regulations. Chemical and mechanical characteristics were studied to determine the variation in properties of selected cements. SO3 content, type and amount of additions, C3A, and C4AF content were used to examine relationships between these characteristics and the results of sulfate resistance. Mortar specimens testing using Na2SO4 as the aggressive medium according to ASTM 1012 (with w/c ratio adapted to prENV 196-X:1995) was performed using each type of cement; identical specimens were also stored in sea water, and in lime saturated water (blank condition), up to five year age. Additionally these cements were tested conforming ASTM 452 and Koch and Steinegger test. Recommended acceptance limits for sulfate resistance of cements concerning to each used test method were evaluated in order to explore their suitability. Relationships between cement characteristics, degradation, expansive products obtained by X-ray diffraction techniques and maximum expansion after applied storage treatments, were correlated at final age, to redefine cement characteristics for sulfate resistant and marine resistant Portland cemen
Inhibiting crypto‐ransomware on windows platforms through a honeyfile‐based approach with R‐Locker
Ministerio de Economia y Competitividad, Grant/Award Number: TIN2017-83494-RAfter several years, crypto‐ransomware attacks still constitute a principal threat for individuals
and organisations worldwide. Despite the fact that a number of solutions are
deployed to fight against this plague, one main challenge is that of early reaction, as
merely detecting its occurrence can be useless to avoid the pernicious effects of the
malware. With this aim, the authors introduced in a previous work a novel antiransomware
tool for Unix platforms named R‐Locker. The proposal is supported on a
honeyfile‐based approach, where ‘infinite’ trap files are disseminated around the target
filesystem for early detection and to effectively block the ransomware action. The authors
extend here the tool with three main new contributions. First, R‐Locker is migrated to
Windows platforms, where specific differences exist regarding FIFO handling. Second,
the global management of the honeyfiles around the target filesystem is now improved to
maximise protection. Finally, blocking suspicious ransomware is (semi)automated
through the dynamic use of white‐/black‐lists. As in the original work for Unix systems,
the new Windows version of R‐Locker shows high effectivity and efficiency in
thwarting ransomware action.Spanish Government TIN2017-83494-
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