1,843 research outputs found

    The Chiloé Mw 7.6 earthquake of 25 December 2016 in Southern Chile and its relation to the Mw 9.5 1960 Valdivia earthquake

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    On 25 December 2016, a Mw 7.6 earthquake broke a portion of the Southern Chilean subduction zone south of Chiloé Island, located in the central part of the Mw 9.5 1960 Valdivia earthquake. This region is characterized by repeated earthquakes in 1960 and historical times with very sparse interseismic activity due to the subduction of a young (~15 Ma), and therefore hot, oceanic plate. We estimate the co-seismic slip distribution based on a kinematic finite fault source model, and through joint inversion of teleseismic body waves and strong motion data. The coseismic slip model yields a total seismic moment of 3.94×1020 Nm that occurred over ~30 s, with the rupture propagating mainly downdip, reaching a peak-slip of ~4.2 m. Regional moment tensor inversion of stronger aftershocks reveals thrust type faulting at depths of the plate interface. The fore- and aftershock seismicity is mostly related to the subduction interface with sparse seismicity in the overriding crust. The 2016 Chiloé event broke a region with increased locking and most likely broke an asperity of the 1960 earthquake. The updip limit of the main event, aftershocks, foreshocks and interseismic activity are spatially similar, located ~15 km offshore and parallel to Chiloé Islands west coast. The coseismic slip model of the 2016 Chiloé earthquake suggests a peak slip of 4.2 m that locally exceeds the 3.38 m slip deficit that has accumulated since 1960. Therefore, the 2016 Chiloé earthquake possibly released strain that has built up prior to the 1960 Valdivia earthquake

    Desempenho mecânico e análise da corrosão das armaduras em concretos produzidos com adição de resíduos de rochas ornamentais

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    Neste trabalho é avaliado o processo de corrosão das armaduras induzido pela ação de íons cloreto em concretos produzidos com adição do Resíduo do Beneficiamento de Rochas Ornamentais (RBRO). No estudo de caracterização, foram avaliadas propriedades físicas, químicas e mineralógicas do RBRO. Foram produzidos concretos com três níveis de relação água/cimento - 0,45; 0,55 e 0,65 -- e quatro níveis de adição de RBRO - 0, 5, 10 e 15%- em relação à massa de cimento. No estado fresco foi avaliada a propriedade de consistência do concreto; no estado endurecido foi avaliada a resistência à compressão axial; as propriedades relacionadas com a durabilidade estudadas foram absorção de água por imersão e fervura, absorção por capilaridade, além de ciclos semanais de indução e aceleração da corrosão por ataque de cloretos e monitoramento do potencial de corrosão. Por último, foi feito o ensaio colorimétrico por aspersão do indicador AgNO3 a 0,1 mol/L. Os resultados mostraram que a adição de RBRO é vantajosa no teor de 5% de RBRO do ponto de vista da resistência mecânica e de durabilidade frente à ação de cloretos.Palavras-chave: durabilidade de concreto armado; corrosão eletroquímica; potencial de corrosão; método colorimétrico; Resíduo do Beneficiamento de Rochas Ornamentais (RBRO)

    Linking Zonal Winds and Gravity II: explaining the equatorially antisymmetric gravity moments of Jupiter

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    The recent gravity field measurements of Jupiter (Juno) and Saturn (Cassini) confirm the existence of deep zonal flows reaching to a depth of 5\% and 15\% of the respective radius. Relating the zonal wind induced density perturbations to the gravity moments has become a major tool to characterise the interior dynamics of gas giants. Previous studies differ with respect to the assumptions made on how the wind velocity relates to density anomalies, on the functional form of its decay with depth, and on the continuity of antisymmetric winds across the equatorial plane. Most of the suggested vertical structures exhibit a rather smooth radial decay of the zonal wind, which seems at odds with the observed secular variation of the magnetic field and the prevailing geostrophy of the zonal winds. Moreover, the results relied on an artificial equatorial regularisation or ignored the equatorial discontinuity altogether. We favour an alternative structure, where the equatorially antisymmetric zonal wind in an equatorial latitude belt between ±21\pm 21^\circ remains so shallow that it does not contribute to the gravity signal. The winds at higher latitudes suffice to convincingly explain the measured gravity moments. Our results indicate that the winds are geostrophic, i.e. constant along cylinders, in the outer 30003000\, km and decay rapidly below. The preferred wind structure is 50\% deeper than previously thought, agrees with the measured gravity moment, is compliant with the magnetic constraints and the requirement of an adiabatic atmosphere and unbiased by the treatment of the equatorial discontinuity

    State-of-the-art on evolution and reactivity

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    This report starts by, in Chapter 1, outlining aspects of querying and updating resources on the Web and on the Semantic Web, including the development of query and update languages to be carried out within the Rewerse project. From this outline, it becomes clear that several existing research areas and topics are of interest for this work in Rewerse. In the remainder of this report we further present state of the art surveys in a selection of such areas and topics. More precisely: in Chapter 2 we give an overview of logics for reasoning about state change and updates; Chapter 3 is devoted to briefly describing existing update languages for the Web, and also for updating logic programs; in Chapter 4 event-condition-action rules, both in the context of active database systems and in the context of semistructured data, are surveyed; in Chapter 5 we give an overview of some relevant rule-based agents frameworks

    Finiteness and children with specific language impairment: an exploratory study

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    Children with specific language impairment (SLI) are well known for their difficulties in mastering the inflectional paradigms; in the case of learning German they also have problems with the appropriate verb position, in particular with the verb in second position. This paper explores the possibilities of applying a broader concept of finiteness to data from children with SLI in order to put their deficits, or rather their skills, into a wider perspective. The concept, as developed by Klein (1998, 2000), suggests that finiteness is tied to the assertion that a certain state of affairs is valid with regard to some topic time; that is, finiteness relates the propositional content to the topic component. Its realization involves the interaction of various grammatical devices and, possibly, lexical means like temporal adverbs. Furthermore, in the acquisition of finiteness it has been found that scope particles play a major role in both first- and second-language learning. The purpose of this paper is to analyze to what extent three German-learning children with SLI have mastered these grammatical and lexical means and to pinpoint the phase in the development of finiteness they have reached. The data to be examined are mostly narrative and taken from conversations and experiments. It will be shown that each child chooses a different developmental path to come to grips with the interaction of these devices

    Aviation fuels of the future − A techno-economic assessment of distribution, fueling and utilizing electricity-based LH2, LCH4 and kerosene (SAF)

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    This paper investigates the techno-economic implications on air travel when fossil-based kerosene is phased out of the market, specifically focusing on the comparison between liquid hydrogen, liquid methane and renewable kerosene for ten exemplary flight routes to estimate the cost of air travel per passenger and 100 km distance travelled for every fuel type. By considering the entire supply chain, including hydrogen production from renewable sources, synthesis, oversea transport, domestic distribution, and utilization, this study addresses the overarching question of whether it is more economical to change the fuel source or the fuel itself to reduce fossil kerosene usage in the aviation industry. It is demonstrated that aircraft acquisition costs play a minor role compared to fuel supply costs and specific fuel demand. The study shows that for electricity-based fuels, liquid hydrogen is the most economic option, even with a potential energy penalty, followed by liquid methane and renewable kerosene. The results for an aircraft with a capacity 180 passengers are 3.08, 4.57 and 5.11 € per 100 passenger kilometers for liquid hydrogen, liquid methane and renewable kerosene, respectively. Challenges regarding storage and isolation requirements for cryogenic fuels in aviation are discussed, with assumptions made that these obstacles can be overcome to realize economic benefits. Additionally, the study suggests potential shifts in aircraft size selection by airlines to mitigate rising fuel prices in the future. The study advocates for the aviation industry's openness to new fuels like liquid hydrogen and liquid methane to alleviate the cost increase associated with phasing out fossil kerosene

    State-of-the-art on evolution and reactivity

    Get PDF
    This report starts by, in Chapter 1, outlining aspects of querying and updating resources on the Web and on the Semantic Web, including the development of query and update languages to be carried out within the Rewerse project. From this outline, it becomes clear that several existing research areas and topics are of interest for this work in Rewerse. In the remainder of this report we further present state of the art surveys in a selection of such areas and topics. More precisely: in Chapter 2 we give an overview of logics for reasoning about state change and updates; Chapter 3 is devoted to briefly describing existing update languages for the Web, and also for updating logic programs; in Chapter 4 event-condition-action rules, both in the context of active database systems and in the context of semistructured data, are surveyed; in Chapter 5 we give an overview of some relevant rule-based agents frameworks

    Ancient DNA Analyses Exclude Humans as the Driving Force Behind Late Pleistocene Musk Ox (Ovibos moschatus) Population Dynamics

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    The causes of the late Pleistocene megafaunal extinctions are poorly understood. Different lines of evidence point to climate change, the arrival of humans, or a combination of these events as the trigger. Although many species went extinct, others, such as caribou and bison, survived to the present. The musk ox has an intermediate story: relatively abundant during the Pleistocene, it is now restricted to Greenland and the Arctic Archipelago. In this study, we use ancient DNA sequences, temporally unbiased summary statistics, and Bayesian analytical techniques to infer musk ox population dynamics throughout the late Pleistocene and Holocene. Our results reveal that musk ox genetic diversity was much higher during the Pleistocene than at present, and has undergone several expansions and contractions over the past 60,000 years. Northeast Siberia was of key importance, as it was the geographic origin of all samples studied and held a large diverse population until local extinction at approximate to 45,000 radiocarbon years before present (14C YBP). Subsequently, musk ox genetic diversity reincreased at ca. 30,000 14C YBP, recontracted at ca. 18,000 14C YBP, and finally recovered in the middle Holocene. The arrival of humans into relevant areas of the musk ox range did not affect their mitochondrial diversity, and both musk ox and humans expanded into Greenland concomitantly. Thus, their population dynamics are better explained by a non-anthropogenic cause (for example, environmental change), a hypothesis supported by historic observations on the sensitivity of the species to both climatic warming and fluctuations

    Nurses Alumni Association Bulletin, Fall 1994

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    1994-1995 Meeting Dates Calendar 1995 Annual Luncheon - Meeting Notice Officers and Committee Chairs Bulletin Publication Committee 1994-1995 Meeting Dates Calendar The President\u27s Message Treasurer\u27s Report News About Our Graduates Fiftieth Anniversary Resume of Minutes of Alumni Association Meetings Department of Nursing 1993-1994 Alumni Office News Jefferson 2000 Fund The Women\u27s Center for Health Promotion Discount Parking for Alumni Cadet Nurse Corps Medical Anecdotes of Faith Ukranian-American Teacher Exchange Happy Birthday Committee Reports In Memoriam, Names of Deceased Graduates Luncheon Photos Class News Jefferson Alumni Identification Card Relief Fund Application Scholarship Application Membership Application Pins, Transcripts, Class Address Lists, Change of address Forms Campus Ma
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