998 resultados para modèle KA


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ka-Map ("ka" as in ka-boom!) is an open source project that is aimed at providing a javascript API for developing highly interactive web-mapping interfaces using features available in modern web browsers. ka-Map currently has a number of interesting features. It sports the usual array of user interface elements such as: interactive, continuous panning without reloading the page; keyboard navigation options (zooming, panning); zooming to pre-set scales; interactive scalebar, legend and keymap support; optional layer control on client side; server side tile caching

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Propuesta didáctica de fonética de la lengua catalana. Cuento interactivo para escolares del ciclo inicial y de educación infantil. Incluye juegos de construcción de palabras con los sonidos de la lengua catalana y actividades de apoyo para el trabajo de logopedia. Resumen tomado de la publicación.

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Le filtrage de Bucy-Kalman s'applique au modèle d'état comprenant des équations linéaires bruitées, décrivant l'évolution de l'état et des équations linéaires bruitées d'observation . Ce filtrage consiste dans le cas gaussien, à calculer de façon récursive, la loi de probabilité, a posteriori, de l'état, au vu de l' observation actuelle et des observations passées . Le filtrage par densités approchées permet de traiter des équations d'état, non linéaires ou à bruits non Gaussiens. Pour un coefficient de rappel aléatoire, cas typique d'une situation de changements de modèles, l'article introduit une famille de lois de probabilité, paramétrées, bimodales servant, par ajustement des paramètres, à approcher les lois a posteriori de l'état aux divers instants . Les paramètres sont recalculés récursivement, lors des mises à jour et des prédictions.

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Subfossil pollen and plant macrofossil data derived from 14C-dated sediment profiles can provide quantitative information on glacial and interglacial climates. The data allow climate variables related to growing season warmth, winter cold, and plant-available moisture to be reconstructed. Continental-scale reconstructions have been made for the mid-Holocene (MH, around 6 ka) and Last Glacial Maximum (LGM, around 21 ka), allowing comparison with palaeoclimate simulations currently being carried out as part of the fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change. The synthesis of the available MH and LGM climate reconstructions and their uncertainties, obtained using modern analogue, regression and model-inversion techniques, is presented for four temperature variables and two moisture variables. Reconstructions of the same variables based on surface-pollen assemblages are shown to be accurate and unbiased. Reconstructed LGM and MH climate anomaly patterns are coherent, consistent between variables, and robust with respect to the choice of technique. They support a conceptual model of the controls of Late Quaternary climate change whereby the first-order effects of orbital variations and greenhouse forcing on the seasonal cycle of temperature are predictably modified by responses of the atmospheric circulation and surface energy balance.

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The 8.2 ka event was triggered by a meltwater pulse (MWP) into the North Atlantic and resultant reduction of the thermohaline circulation (THC). This event was preceded by a series of at least 14 MWPs; their impact on early Holocene climate has remained almost unknown. A set of high-quality paleoclimate records from across the Northern Hemisphere shows evidence for a widespread and significant climatic anomaly at ∼9.2 ka B.P. This event has climatic anomaly patterns very similar to the 8.2 ka B.P. event, cooling occurred at high latitudes and midlatitudes and drying took place in the northern tropics, and is concurrent with an MWP of considerable volume (∼8100 km3). As the 9.2 ka MWP occurs at a time of enhanced baseline freshwater flow into the North Atlantic, this MWP may have been, despite its relatively small volume, sufficient to weaken THC and to induce the observed climate anomaly pattern.

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There are many geochemical reconstructions of environmental change in the mid and high latitudes but relatively few in the tropical latitudes, despite their considerable potential for reconstructing environmental processes that cannot be identified using more traditional proxies. Here we present one reconstruction of environmental change for the tropics. This reconstruction covers the past 50 ka using a suite of geochemical data from the high-resolution sequence of Lynch's Crater in northeast Queensland, Australia, a region highly sensitive to El Niño-Southern Oscillation (ENSO) activity. The 23 major oxides and trace elements measured could be summarised by extracting three axes using principal components analysis (accounting for 72% of the variability). The data indicate that the greatest variability in the geochemical data accounted for erosional activity within the catchment that was associated with past changes in the frequency of ENSO activity (though this was less sensitive during wetter periods, probably as a result of buffering by high vegetation cover). The remaining variability was largely explained by elements that form complexes with organic compounds (e.g., humic acids) and those that are important nutrients for specific vegetation types (and therefore a measure of vegetation distribution). For more detailed reconstructions, further work is required to disentangle the complex controls of elements within sedimentary sequences.

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High-resolution pollen and dinoflagellate cyst records from sediment core M72/5-25-GC1 were used to reconstruct vegetation dynamics in northern Anatolia and surface conditions of the Black Sea between 64 and 20 ka BP. During this period, the dominance of Artemisia in the pollen record indicates a steppe landscape and arid climate conditions. However, the concomitant presence of temperate arboreal pollen suggests the existence of glacial refugia in northern Anatolia. Long-term glacial vegetation dynamics reveal two major arid phases ~64–55 and 40–32 ka BP, and two major humid phases ~54–45 and 28–20 ka BP, correlating with higher and lower summer insolation, respectively. Dansgaard–Oeschger (D–O) cycles are clearly indicated by the 25-GC1 pollen record. Greenland interstadials are characterized by a marked increase in temperate tree pollen, indicating a spread of forests due to warm/wet conditions in northern Anatolia, whereas Greenland stadials reveal cold and arid conditions as indicated by spread of xerophytic biomes. There is evidence for a phase lag of ~500 to 1500 yr between initial warming and forest expansion, possibly due to successive changes in atmospheric circulation in the North Atlantic sector. The dominance of Pyxidinopsis psilata and Spiniferites cruciformis in the dinocyst record indicates brackish Black Sea conditions during the entire glacial period. The decrease of marine indicators (marine dinocysts, acritarchs) at ~54 ka BP and increase of freshwater algae (Pediastrum, Botryococcus) from 32 to 25 ka BP reveals freshening of the Black Sea surface water. This freshening is possibly related to humid phases in the region, to connection between Caspian Sea and Black Sea, to seasonal freshening by floating ice, and/or to closer position of river mouths due to low sea level. In the southern Black Sea, Greenland interstadials are clearly indicated by high dinocyst concentrations and calcium carbonate content, as a result of an increase in primary productivity. Heinrich events show a similar impact on the environment in the northern Anatolia/Black Sea region as Greenland stadials.

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Climate change is often cited as a major factor in social change. The so-called 8.2 ka event was one of the most pronounced and abrupt Holocene cold and arid events. The 9.2 ka event was similar, albeit of a smaller magnitude. Both events affected the Northern Hemisphere climate and caused cooling and aridification in Southwest Asia. Yet, the impacts of the 8.2 and 9.2 ka events on early farming communities in this region are not well understood. Current hypotheses for an effect of the 8.2 ka event vary from large-scale site abandonment and migration (including the Neolithisation of Europe) to continuation of occupation and local adaptation, while impacts of the 9.2 ka have not previously been systematically studied. In this paper, we present a thorough assessment of available, quality-checked radiocarbon (14C) dates for sites from Southwest Asia covering the time interval between 9500 and 7500 cal BP, which we interpret in combination with archaeological evidence. In this way, the synchronicity between changes observed in the archaeological record and the rapid climate events is tested. It is shown that there is no evidence for a simultaneous and widespread collapse, large-scale site abandonment, or migration at the time of the events. However, there are indications for local adaptation. We conclude that early farming communities were resilient to the abrupt, severe climate changes at 9250 and 8200 cal BP.

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The potential impact of the abrupt 8.2 ka cold event on human demography, settlement patterns and culture in Europe and the Near East has emerged as a key theme in current discussion and debate. We test whether this event had an impact on the Mesolithic population of western Scotland, a case study located within the North Atlantic region where the environmental impact of the 8.2 ka event is likely to have been the most severe. By undertaking a Bayesian analysis of the radiocarbon record and using the number of activity events as a proxy for the size of the human population, we find evidence for a dramatic reduction in the Mesolithic population synchronous with the 8.2 ka event. We interpret this as reflecting the demographic collapse of a low density population that lacked the capability to adapt to the rapid onset of new environmental conditions. This impact of the 8.2 ka event in the North Atlantic region lends credence to the possibility of a similar impact on populations in Continental Europe and the Near East.

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Syfte: Syftet med denna studie var att undersöka vilka metoder som kan användas av sjuksköterskor för att uppnå följsamhet gällande genomförande av livsstilsförändringar hospatienter med diabetes typ 2 samt effekten av dessa. Metod: Uppsatsen har genomförts somen systematisk litteraturstudie. Artiklar har sökts i databaserna ELIN@Dalarna, Cinahl samtPubMed. Endast vetenskapliga artiklar som har publicerats mellan 2003 och 2008, tillgängligai fulltext, har inkluderats. Sexton kvantitativa artiklar ligger till grund för resultatdelen.Resultat: Användandet av telefonsamtal som hjälpmedel för sjuksköterskan att nå ut tilldiabetespatienterna har visat sig kunna öka diabetespatienters följsamhet vad gäller dieten.Automatiserade telefonsamtal har påvisats kunna hjälpa till att öka följsamheten gällandefysisk aktivitet. Även SMS som kommunikationsmedel mellan sjuksköterskan och patientenhar visat sig kunna öka följsamheten gällande fysisk aktivitet. Genom användandet utavvideokonferensutrustning för informering kring bland annat kost, motion och diabetessymtomhar en påtagbar livsstilsförändring kring diet kunnat påvisas.

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Syftet med denna studie var att undersöka hur lärare som undervisar i år 3 till 9 på en skola, medvetet arbetar med läsning och tränar elevers läsförståelse och läsförmåga. Syftet var även att se hur läsundervisningen på skolan förhåller sig till Frank Smiths och Caroline Libergs teorier om läsning. Undersökningen genomfördes i två delar, dels genom enkätstudie och dels genom läroboksanalys av två läroböcker som används på skolan. Enkäten besvarades av fyra klasslärare och nitton ämneslärare på skolan. Resultaten visade att majoriteten av lärarna har formell utbildning om hur läsförmågan utvecklas, men flertalet anser att deras kompetens inte räcker till för att hjälpa eleverna att bli bättre läsare. Majoriteten använder också undervisningsmetoder där eleverna får öva läsförmågan minst en gång i veckan. De flesta lärarna använder läroböcker regelbundet och av de analyserade böckerna ansågs historieboken inte ha ett särskilt meningsfull innehåll medan svenskboken ansågs ha ett meningsfullt textinnehåll.

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Syftet med denna studie var att undersöka vilka icke-farmakologiska omvårdnadsåtgärder som bidrar till reducerad förekomst av beteendestörningar och ökar välbefinnandet hos personer med demens. Studien utfördes som en systematisk litteraturstudie där 15 artiklar inkluderades. Icke-farmakologiska omvårdnadsåtgärder som inkluderades i den här studien var musik, aktivitet och träning och massage och beröring. Beteendestörningar framför allt agitation kan lindras med hjälp av massage och beröring, aktivitet samt musikterapi i olika former. Det är viktigt att utforma alla dessa omvårdnadsåtgärder utifrån individen för att erhålla ett gott resultat. Även välbefinnandet påverkas positivt av dessa icke-farmakologiska omvårdnadsåtgärder. Fördelarna med dessa omvårdnadsåtgärder är att de är enkla att utföra och lära ut, kostnadseffektiva och har få biverkningar. I denna litteraturstudie framgår även att det sociala samspelat har en viktig roll för att personer med demens upplever välbefinnande. Slutsatsen är att det borde vara enkelt att använda sig av dessa effektiva metoder i både demensvård och annan vård.

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Studiens syfte är att med hjälp av denna systematiska litteraturstudie undersöka om förändringar inom teknikämnet i årskurs 1-6 kan öka flickors teknikintresse. Frågeställningen som det sökts svar på i aktuell internationell forskning, är följande: Anser aktuell forskning att skolan bör förändras för att öka teknikintresset hos flickor i årskurs 1-6, och i så fall, varför och på vilket sätt? För att få svar på frågeställningarna har systematiska sökningar i databaserna Eric (Proquest), Summon och www.avhandlingar.se gjorts. Engelska sökord som är aktuella för ämnet har valts ut för att ge en bred men ändå riktad sökning. Resultatet till studien är baserad på två avhandlingar och fem artiklar, varav en artikel är en metaanalys och fyra är forskningsstudier. Resultatet visar att flickors teknikintresse kan öka med hjälp av en mer genusmedveten undervisning som tar hänsyn till flickor och pojkars olika intressen. Det har också visat sig att det är av stor vikt för flickor att få en tidig god teknikundervisning för att öka självförtroendet inom ämnet, då val till framtida utbildningar och yrken görs tidigt. För att dessa åtgärder ska kunna genomföras krävs det att lärare och skolledare får mer utbildning i ämnet teknik och hur en genusmedveten undervisning kan bedrivas.  

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The paleoclimatic record of Jureia Paleolagoon, coastal southeastem Brazil, includes cyclic and gradual changes with different intensities and frequencies through geological time, and it is controlled by astronomical, geophysical, and geological phenomena. These variations are not due to one single cause, but they result from the interaction of several factors, which act at different temporal and spatial scales. Here, we describe paleoenvironmental evidence regarding climatic and sea level changes from the last 9400 cal yr BP at the Jureia Paleolagoon - one of the main groups of protected South Atlantic ecosystems. Geochemical evidences were used to identify anomalies from multi-proxy analyses of a paleolagoon sediment core. The anomalies of centennial scale were correlated to climate and transgression-regression cycles from the Holocene period. Decadal scale anomalous oscillations in the Quaternary paleolagoon sediments occur between 9400 and 7500 cal yr BP, correlated with long- and short-term natural events, which generated high sedimentation rates, mainly between 8385 and 8375 cal yr BP (10 cm/yr). Our results suggest that a modem-day short-duration North Atlantic climatic event, such as the 82 ka event, could affect the environmental equilibrium in South America and intensify the South American Summer Monsoon. (C) 2011 University of Washington. Published by Elsevier Inc. All rights reserved.

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Millennial variability is a robust feature of many paleoclimate records, at least throughout the last several glacial cycles. Here we use the mean signal from Antarctic climate events 1 to 4 to probe the EPICA Dome C temperature proxy reconstruction through the last 500 ka for similar millennial-scale events. We find that clusters of millennial events occurred in a regular fashion over half of the time during this with a mean recurrence interval of 21 kyr. We find that there is no consistent link between ice-rafted debris deposition and millennial variability. Instead we speculate that changes in the zonality of atmospheric circulation over the North Atlantic form a viable alternative to freshwater release from icebergs as a trigger for millennial variability. We suggest that millennial changes in the zonality of atmospheric circulation over the North Atlantic are linked to precession via sea-ice feedbacks and that this relationship is modified by the presence of the large, Northern Hemisphere ice sheets during glacial periods.