964 resultados para Continental Drift


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An important application of Big Data Analytics is the real-time analysis of streaming data. Streaming data imposes unique challenges to data mining algorithms, such as concept drifts, the need to analyse the data on the fly due to unbounded data streams and scalable algorithms due to potentially high throughput of data. Real-time classification algorithms that are adaptive to concept drifts and fast exist, however, most approaches are not naturally parallel and are thus limited in their scalability. This paper presents work on the Micro-Cluster Nearest Neighbour (MC-NN) classifier. MC-NN is based on an adaptive statistical data summary based on Micro-Clusters. MC-NN is very fast and adaptive to concept drift whilst maintaining the parallel properties of the base KNN classifier. Also MC-NN is competitive compared with existing data stream classifiers in terms of accuracy and speed.

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Offsite pesticide losses in tropical mountainous regions have been little studied. One example is measuring pesticide drift soil deposition, which can support pesticide risk assessment for surface water, soil, bystanders, off target plants and fauna. This is considered a serious gap, given the evidence of pesticide-related poisoning in those regions. Empirical data of drift deposition of a pesticide surrogate, Uranine tracer, within one of the highest potato producing regions in Colombia, characterized by small plots and mountain orography, is presented. High drift values encountered in our study reflect the actual spray conditions using handled knapsack sprayers. Comparison between measured and predicted drift values using three existing empirical equations showed important underestimation. However, after their optimization based on measured drift information, the equations showed a strong predictive power for this study area and the study conditions. The most suitable curve to assess mean relative drift was the IMAG calculator after optimization.

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Floods are the most frequent of natural disasters, affecting millions of people across the globe every year. The anticipation and forecasting of floods at the global scale is crucial to preparing for severe events and providing early awareness where local flood models and warning services may not exist. As numerical weather prediction models continue to improve, operational centres are increasingly using the meteorological output from these to drive hydrological models, creating hydrometeorological systems capable of forecasting river flow and flood events at much longer lead times than has previously been possible. Furthermore, developments in, for example, modelling capabilities, data and resources in recent years have made it possible to produce global scale flood forecasting systems. In this paper, the current state of operational large scale flood forecasting is discussed, including probabilistic forecasting of floods using ensemble prediction systems. Six state-of-the-art operational large scale flood forecasting systems are reviewed, describing similarities and differences in their approaches to forecasting floods at the global and continental scale. Currently, operational systems have the capability to produce coarse-scale discharge forecasts in the medium-range and disseminate forecasts and, in some cases, early warning products, in real time across the globe, in support of national forecasting capabilities. With improvements in seasonal weather forecasting, future advances may include more seamless hydrological forecasting at the global scale, alongside a move towards multi-model forecasts and grand ensemble techniques, responding to the requirement of developing multi-hazard early warning systems for disaster risk reduction.

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This study aims at the determination of a Fram Strait cyclone track and of the cyclone’s impact on ice edge, drift, divergence, and concentration. A 24 h period on 13–14 March 2002 framed by two RADARSAT images is analyzed. Data are included from autonomous ice buoys, a research vessel, Special Sensor Microwave Imager (SSM/I) and QuikSCAT satellite, and the operational European Centre for Medium-Range Weather Forecasts (ECMWF) model. During this 24 h period the cyclone moved northward along the western ice edge in the Fram Strait, crossed the northern ice edge, made a left-turn loop with 150 km diameter over the sea ice, and returned to the northern ice edge. The ECMWF analysis places the cyclone track 100 km too far west over the sea ice, a deviation which is too large for representative sea ice simulations. On the east side of the northward moving cyclone, the ice edge was pushed northward by 55 km because of strong winds. On the rear side, the ice edge advanced toward the open water but by a smaller distance because of weaker winds there. The ice drift pattern as calculated from the ice buoys and the two RADARSAT images is cyclonically curved around the center of the cyclone loop. Ice drift divergence shows a spatial pattern with divergence in the loop center and a zone of convergence around. Ice concentration changes as retrieved from SSM/I data follow the divergence pattern such that sea ice concentration increased in areas of divergence and decreased in areas of convergence.

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Several biotic crises during the past 300 million years have been linked to episodes of continental flood basalt volcanism, and in particular to the release of massive quantities of magmatic sulphur gas species. Flood basalt provinces were typically formed by numerous individual eruptions, each lasting years to decades. However, the environmental impact of these eruptions may have been limited by the occurrence of quiescent periods that lasted hundreds to thousands of years. Here we use a global aerosol model to quantify the sulphur-induced environmental effects of individual, decade-long flood basalt eruptions representative of the Columbia River Basalt Group, 16.5–14.5 million years ago, and the Deccan Traps, 65 million years ago. For a decade-long eruption of Deccan scale, we calculate a decadal-mean reduction in global surface temperature of 4.5 K, which would recover within 50 years after an eruption ceased unless climate feedbacks were very different in deep-time climates. Acid mists and fogs could have caused immediate damage to vegetation in some regions, but acid-sensitive land and marine ecosystems were well-buffered against volcanic sulphur deposition effects even during century-long eruptions. We conclude that magmatic sulphur from flood basalt eruptions would have caused a biotic crisis only if eruption frequencies and lava discharge rates had been high and sustained for several centuries at a time.

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The occurrence of directional microphone drift following hearing aid use has been infrequently examined. This study uses the front-to-side ratio to evaluate changes in directional microphone output from new behind-the-ear hearing aids and following approximately three months of hearing aid use. Results indicate no overall significant differences in the front-to-side ratio between initial and follow-up measurements.

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Electromagnetic induction (EMI) method results are shown for vertical magnetic dipole (VMD) configuration by using the EM38 equipment. Performance in the location of metallic pipes and electrical cables is compared as a function of instrumental drift correction by linear and quadratic adjusting under controlled conditions. Metallic pipes and electrical cables are buried at the IAG/USP shallow geophysical test site in Sao Paulo City. Brazil. Results show that apparent electrical conductivity and magnetic susceptibility data were affected by ambient temperature variation. In order to obtain better contrast between background and metallic targets it was necessary to correct the drift. This correction was accomplished by using linear and quadratic relation between conductivity/susceptibility and temperature intending comparative studies. The correction of temperature drift by using a quadratic relation was effective, showing that all metallic targets were located as well deeper targets were also improved. (C) 2010 Elsevier B.V. All rights reserved.

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The present paper reports on 22 species collected by the Brazilian Program of Living Resources in the Exclusive Economic Zone (REVIZEE). A new genus and species of Cribrilinidae, Corbuliporina crepida n. gen. et sp., is described, along with seventeen other new species: Chaperia brasiliensis n. sp., Amastigia aviculifera n. sp., Isosecuriflustra pinniformis n. sp., Cellaria subtropicalis n. sp., Melicerita brasiliensis n. sp., Arachnopusia haywardi n. sp., Smittina migottoi n. sp., Hippomenella amaralae n. sp., Rogicka joannae n. sp., Malakosaria atlantica n. sp., Turbicellepora winstonae n. sp., Rhynchozoon coalitum n. sp., Stephanollona angusta n. sp., Stephanollona arborescens n. sp., Aulopocella americana n. sp., Conescharellina cookae n. sp. and Conescharellina bocki n. sp. Chorizopora brongniartii (Audouin, 1826) is recorded for the first time in Brazilian waters and a new combination for Rhynchozoon arborescens Canu & Bassler, 1928 is established. New illustrations and taxonomic remarks are included for two little-known species from Brazil, Rogicka scopae (Canu & Bassler, 1928) and Fenestrulina ampla Canu & Bassler, 1928. A compilation of species recorded from deeper waters of the Brazilian coast is included.

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A new genus and species of Normanellidae (Copepoda, Harpacticoida), Paranaiara inajae gen. et sp. nov., is described from the continental shelf off the northern coast of Sao Paulo State, Brazil. The new genus differs from the type genus Normanella Brady, 1880 and Sagamiella Lee & Huys, 1999 in its presence of lamelliform caudal rami, a maxillulary endopod represented by 2 setae, an unarmed maxillipedal syncoxa, and reduced setation on P2 enp-2 (without outer spine) and P3 enp-2 (with only 2 inner setae). All these apomorphic character states are shared with the genus Pseudocletodes Scott & Scott, 1893, formerly placed in the family Nannopodidae (ex Huntemanniidae) and here assigned to the Normanellidae. Pseudocletodes can be differentiated from Paranaiara by the loss of the P1 endopod and of the inner seta on P2-P4 enp-1, the presence of only 2 inner setae on P2 enp-2 (instead of 3) and only 1 inner seta on P4 exp-3 (instead of 2), the presence of a second inner seta on P4 enp-2 (instead of 1), the morphology of the fifth pair of legs which are not medially fused and have only 3 endopodal elements (instead of 4) in the male, and the well developed caudal ramus seta V (instead of rudimentary). It is postulated that prehensility of the P1 endopod was secondarily lost in the common ancestor of Paranaiara and Pseudocletodes. An updated family diagnosis of the Normanellidae and a dichotomous identification key to the 22 currently valid species are presented.

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För att kunna bygga en ny väg måste den först planeras och projekteras. Vägplanering innebär att man undersöker förutsättningarna för att bygga vägen t.ex. konsekvenser för miljö, samhälle, trafiksäkerhet, framkomlighet, tillgänglighet samt tekniska och ekonomiska förutsättningar. Vägprojektering innebär att man bestämmer vägens utformning på detaljnivå t.ex. vägsträckning, bredd, profil, vägutrustning, etc. Planering och projektering av vägar är en komplicerad process med tanke på alla komponenter som en väg består av samt alla aspekter som man måste ta hänsyn till under vägens livstid. Planerings- och projekteringsprocessen utgör en avvägning av många aspekter för att hitta den optimala lösningen. Drift- och underhållsåtgärder på vägnätet föranleds ofta av att problem uppstått på ett fåtal ställen. Kostnaden för att åtgärda dessa ställen kan uppgå till stora belopp under vägens livslängd. Med en lämpligare utformning av vägen hade dessa problem i en del fall sannolikt kunnat undvikas. Bland de aktörer, som är inblandade i planerings- och projekteringsprocessen, finns det olika åsikter om orsaken till att man inte tar tillräcklig hänsyn till drift- och underhållaspekten under planerings- och projekteringsskedet. Vissa aktörer tycker att det är projektörens kunskapsbrister som leder till att vägen får olämplig utformning avseende drift och underhåll. Andra tycker att det är en kombination av olika brister hos väghållaren. Dessa brister kan då finnas i såväl planerings- och projekteringsprocessen som i drift- och underhållsprocessen. Denna rapport presenterar resultatet för en förstudie som har utförts inom doktorandprojektet ”Vägprojektering för minskade drift- och underhållskostnader”. Syftet med förstudien var att identifiera brister och problem på övergripande nivå som leder till att man inte tar tillräcklig hänsyn till drift- och underhållsaspekten vid planerings- och projekteringsprocessen. Ett annat syfte med förstudien var att föreslå förändringsbehov inom planerings- och projekteringsprocessen genom att analysera de identifierade problemen, analysera verksamheten vid planering och projektering, analysera verksamhetens mål, formulera nya mål för verksamheten och fastställa de nödvändiga förändringsbehoven.

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Em 1982 o Brasil participa da Convenção das Nações Unidas para o Direito do Mar. Esta convenção dispõe sobre os usos dos espaços marítimos e oceânicos, buscando a utilização racional e a exploração dos recursos do mar. Devido ao escasso conhecimento da região da plataforma externa e talude continental, surge o programa Avaliação do Potencial Sustentável de Recursos Vivos da Zona Econômica Exclusiva – REVIZEE, tanto para a diversificação da exploração pesqueira quanto para a determinação dos limites sustentáveis de captura. Com base em material coletado em abril de 1998, durante campanha de Bentos concernente ao programa REVIZEE, são fornecidos resultados relativos a Gastropoda encontrados na radial 45, estações hidrográficas 6839 (32o55´70´´S - 50o34´60´´W), 6840 (33o01´45´´S - 50o12´75´´W), 6841 (33o00´16´´S - 50o22´84´´W) e 6842 (32o57´81´´S - 50o29´18´´W), localizadas ao largo de Rio Grande, Rio Grande do Sul, Brasil. Para a avaliação da diversidade bêntica foram utilizados três tipos de amostradores de fundo; Draga de arrasto, Box Corer e Van Veen. Molluscos foram separados dos demais grupos taxonômicos pela equipe do REVIZEE e recebidos pelo laboratório de malacologia da Universidade Federal do Rio Grande do Sul. O material foi triado sob lupa Zeiss Stemi 2000- C ou Wild M-38. O material foi identificado por comparação com os dados da bibliografia e/ou por comparação com exemplares depositados nas coleções do Museu Oceanográfico Eliézer de Carvalho Rios (MORG) e/ou com a coleção particular do Dr. José Carlos Tarasconi São identificados e caracterizados quanto a tamanho, esculturação e área de ocorrência 6.020 exemplares distribuídos em 36 famílias - 80 táxons em nível de espécie, 19 em nível de gênero e 2 em nível de família. A família Turridae é a que apresenta o maior número de táxons com 16 espécies. Turritella hookeri Reeve, 1849 é a espécie mais abundante, com 684 exemplares. Registra-se pela primeira vez para o Rio Grande do Sul as seguintes espécies: Brookula conica (Watson, 1886), Calliostoma echinatum Dall, 1881, Solariela carvalhoi Lopes & Cardoso, 1958, Caecum massambabensis Absalão, 1994, Turritella hookeri Reeve, 1849, Crepidula plana Say, 1822, Natica pusilla Say, 1822, Polinices lacteus (Guilding, 1833), Eulima mulata Rios & Absalão, 1990, Melanella aff. hypsela (Verrill & Bush, 1900), Trachipollia turricula (von Maltzan, 1884), Anachis sparsa Reeve, 1859, Dentimargo janeiroensis (E. A. Smith, 1915), Axelella brasiliensis Verhecken, 1991, Drilliola loprestiana (Calcara, 1841), Mitrolumna biplicata (Dall, 1889), Nannodiella vespuciana (Orbigny, 1842), Stenodrillia goundlachi (Dall & Simpson, 1901), Terebra brasiliensis E. A. Smith, 1873 e Mathilda aff. scitula Dall, 1889. Novos limites de profundidade são registrados para 29 espécies. Com base na lista de espécies encontradas, se discute sobre o limite das Províncias Caribenha e Patagônica e sobre a influência da Laguna dos Patos no Talude Continental ao largo de Rio Grande.