Influence of concrete composition on anchorage bond behavior of prestressing reinforcement

An experimental research addressing the effects of concrete composition and strength on anchorage bond behavior of prestressing reinforcement is presented to clarify the effect of material properties that have appeared contradictory in previous literature. Bond stresses and anchorage lengths have been obtained in twelve concrete mixes made up of different cement contents (C) – 350 to 500 kg/m3 – and water/cement (w/c) ratios – 0.3 to 0.5 – with compressive strength at 24 h ranging from 24 to 55 MPa. A testing technique based on measuring the prestressing force in specimens with different embedment lengths has been used. The results show that anchorage length increases when w/c increases, more significantly when C is higher; the effect of C reveals different trends based on w/c. The obtained anchorage bond stresses are greater for higher concrete compressive strength, and their average ratio of 1.45 with respect to transmission bond stresses implies a potential bond capacity.

Tephra from andesitic Shiveluch volcano, Kamchatka, NW Pacific: chronology of explosive eruptions and geochemical fingerprinting of volcanic glass

The ~16-ka-long record of explosive eruptions from Shiveluch volcano (Kamchatka, NW Pacific) is refined using geochemical fingerprinting of tephra and radiocarbon ages. Volcanic glass from 77 prominent Holocene tephras and four Late Glacial tephra packages was analyzed by electron microprobe. Eruption ages were estimated using 113 radiocarbon dates for proximal tephra sequence. These radiocarbon dates were combined with 76 dates for regional Kamchatka marker tephra layers into a single Bayesian framework taking into account the stratigraphic ordering within and between the sites. As a result, we report ~1,700 high-quality glass analyses from Late Glacial–Holocene Shiveluch eruptions of known ages. These define the magmatic evolution of the volcano and provide a reference for correlations with distal fall deposits. Shiveluch tephras represent two major types of magmas, which have been feeding the volcano during the Late Glacial–Holocene time: Baidarny basaltic andesites and Young Shiveluch andesites. Baidarny tephras erupted mostly during the Late Glacial time (~16–12.8 ka BP) but persisted into the Holocene as subordinate admixture to the prevailing Young Shiveluch andesitic tephras (~12.7 ka BP–present). Baidarny basaltic andesite tephras have trachyandesite and trachydacite (SiO₂ < 71.5 wt%) glasses. The Young Shiveluch andesite tephras have rhyolitic glasses (SiO₂ > 71.5 wt%). Strongly calc-alkaline medium-K characteristics of Shiveluch volcanic glasses along with moderate Cl, CaO and low P₂O₅ contents permit reliable discrimination of Shiveluch tephras from the majority of other large Holocene tephras of Kamchatka. The Young Shiveluch glasses exhibit wave-like variations in SiO₂ contents through time that may reflect alternating periods of high and low frequency/volume of magma supply to deep magma reservoirs beneath the volcano. The compositional variability of Shiveluch glass allows geochemical fingerprinting of individual Shiveluch tephra layers which along with age estimates facilitates their use as a dating tool in paleovolcanological, paleoseismological, paleoenvironmental and archeological studies. Electronic tables accompanying this work offer a tool for statistical correlation of unknown tephras with proximal Shiveluch units taking into account sectors of actual tephra dispersal, eruption size and expected age. Several examples illustrate the effectiveness of the new database. The data are used to assign a few previously enigmatic wide-spread tephras to particular Shiveluch eruptions. Our finding of Shiveluch tephras in sediment cores in the Bering Sea at a distance of ~600 km from the source permits re-assessment of the maximum dispersal distances for Shiveluch tephras and provides links between terrestrial and marine paleoenvironmental records.

Gestão de risco: caso da Sonae Indústria

Dissertação para a obtenção do Grau de Mestre em Auditoria Orientador: Mestre Carlos Manuel Antunes Mendes

Ordenamento turístico-sustentável em áreas fragilizadas

O aumento da participação de destinos tidos como “exóticos” no segmento turístico gerou expectativas em muitas regiões do planeta, especialmente nas que apresentam maiores carências a nível económico. A participação no circuito turístico sem precauções de sustentabilidade está na origem do avolumar de fragilidades nas restantes potencialidades naturais e sociais levando, mesmo, à adulteração da identidade local com prejuízo para os recursos aí existentes. A consciencialização de resultados negativos para com o ambiente fez com que as classes envolvidas no sector do turismo conciliassem esforços na defesa das regiões, comunidades e causas ambientais, obrigando os intervenientes a melhorar as políticas de exploração turística e promovendo uma maior participação das gentes locais nos processos. A adesão de Cabo Verde ao circuito turístico, caracterizada pela consciência da potencialidade dos seus valores naturais, humanos e tradicionais necessita, todavia, da implementação de políticas no contexto de um Ordenamento do sector do Turismo com vista a atingir resultados sustentáveis em apoio à frágil situação económica das suas regiões. Neste contexto, a ilha de Santo Antão surge como região de grandes potencialidades, graças ao reconhecimento das suas qualidades. Tendo em consideração a procura crescente no sector, na ilha, pretende-se, com este estudo, contribuir para que o desenvolvimento económico da região se possa desenvolver com base na utilização dos seus recursos, não só pela melhoria das comunidades pelo aumento de emprego e rendimentos, mas também pelo reforço da vida comunitária, da melhoria do bem-estar e da integração social dos residentes e pelo desenvolvimento cultural de toda a ilha. A procura de um turismo com preocupações ambientais conduz à solução dos “3 L’s”, “(Lore, Landscape and Leisure – Tradições, Paisagem e Repouso)”, situação em que Santo Antão é rica, a par dos tipos de turismo científico, de montanha e rural, também disponíveis.

De touch: extending service channels in an airport through touch technologies

This project aimed to create a communication and interaction channel between Madeira Airport and its passengers. We used the pre-existent touch enabled screens at the terminal since their potential was not being utilised to their full capacity. To achieve our goal, we have followed an agile strategy to create a testable prototype and take advantages of its results. The developed prototype is based on a plugin architecture turning it into a maintainable and highly customisable system. The collected usage data suggests that we have achieved the initially defined goals. There is no doubt that this new interaction channel is an improvement regarding the provided services and, supported by the usage data, there is an opportunity to explore additional developments to the channel.

Prevalence of overweight and obesity among migrants in Switzerland: association with country of origin.

Migrants tend to present higher overweight and obesity levels, but whether this relationship applies to all nationalities has seldom been studied. The present study aimed to assess the prevalence of overweight and obesity according to nationality in adults. Cross-sectional population-based samples. Five-year nationwide interview surveys (Swiss Health Surveys - SHS) from 1992 to 2007 (n 63 766) and a local examination survey (CoLaus Study in Lausanne 2004-2006, n 6743). Participants were separated into Swiss, French, German, Italian, Portuguese, Spanish nationals, those from the former Republic of Yugoslavia and from other European and other countries. Compared with Swiss nationals, German and French nationals presented a lower prevalence of overweight and obesity, whereas nationals from Italy, Spain, Portugal and the former Republic of Yugoslavia presented higher levels. Adjusting the SHS data for age, gender, education, smoking, leisure-time physical activity and survey year, a lower risk for overweight and obesity was found for German (OR = 0·80, 95 % CI 0·70, 0·92) and French (OR = 0·74, 95 % CI 0·61, 0·89) nationals, whereas higher risks were found for participants from Italy (OR = 1·45, 95 % CI 1·33, 1·58), Spain (OR = 1·36, 95 % CI 1·15, 1·61), Portugal (OR = 1·25, 95 % CI 1·06, 1·47) and the former Republic of Yugoslavia (OR = 1·98, 95 % CI 1·69, 2·32). Similar findings were observed in the CoLaus Study for Italian (OR = 1·63, 95 % CI 1·29, 2·06), Spanish (OR = 1·54, 95 % CI 1·17, 2·04) and Portuguese (OR = 1·49, 95 % CI 1·16, 1·91) participants and for those from the former Republic of Yugoslavia (OR = 5·34, 95 % CI 3·00, 9·50). Overweight and obesity are unevenly distributed among migrants in Switzerland. Migrants from Southern Europe and from the former Republic of Yugoslavia present higher prevalence rates. This suggests that preventive messages should be tailored to these specific populations.

Identificación del fenomeno "El niño" a través de organismos fitoplanctónicos

Analiza los indicadores del movimiento de aguas ecuatoriales superficiales, subtropicales y aguas frías, indicando su inicio, intensidad y extensión.

L'Écho de Paris

1887/05/17 (Numéro 1156).

« Receuil de la généalogie de la noble maison de Luxembourg ».

Armorial contenant les blasons coloriés des familles issues de Charles, comte de Luxembourg (1156), et des notices historiques sur chacune d'elles. — Il a été composé sous le règne de François Ier.

Français 920

Contient : 1° « Le Livre de maistre PIERRE ABAIELART et de ses espitres, et les espitres que HELOYS lui renvouoit, et la response que maistre Pierre lui faisoit encontre », traduction [de JEAN DE MEUNG] ; 2° « La Confession de ABAELARD à Heloys, jadis sa feme » ; 3° « La Confession d'ABAELART general et especial contre aucune articlez contre lui imposez » ; 4° « L'Espitre de PIERRE, abbé de Clugny, envoyée à Heloïs, lors abbesse du Paraclit, translatée de latin en françoys, en laquelle recommande le dit la vie et la personne de la dite Heloys, et la vie et la mort de maistre P. Abaelart, lors novellement trespassé à Saint Marcel delez Chalon sur la Sone »

Cómo aplicar soluciones creativas a los problemas de tu empresa. Documento de preguntas y respuestas

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