621 research outputs found

    Dimensional Accuracy in X-Ray Computed Tomography Imaging

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    X-ray computed tomography (CT) has become an important non-destructive evaluation technique. CT contributes to a wide range of nondestructive evaluation (NDE) applications [1]. These include typical NDE applications (e.g., defect detection and quality control), more advanced NDE applications (e.g., process development and model verification), and the more recent application of CT-based metrology (e.g., geometric inspection and reverse engineering). In the traditional applications of CT, the user is concerned with defect sensitivity, which is a combination of spatial resolution, contrast sensitivity and slice thickness [2]. For CT-based metrology, the term “defect sensitivity” has little meaning; dimensional accuracy of the system becomes paramount

    Controle automático da umidade do solo com energia solar para pequenos produtores.

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    Esse trabalho tem por objetivo apresentar um protótipo autônomo de irrigação energizado por uma célula fotovoltaica de 5 W, baseado na plataforma Arduino (código e hardware aberto). O sistema consiste de um sensor de umidade do solo que ao atingir um dado sinal elétrico aciona um dispositivo solenoide de liberação do fluxo de água em uma rede de irrigação. O sistema tem custo aproximado de R$240, é de fácil manipulação e manutenção, e funciona de maneira autônoma durante o dia quando há energia solar disponível. O emprego do sistema pode aumentar a produtividade de pequenos produtores pela redução do estresse em períodos de seca

    Infrared Nonlinear Optics

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    Contains report on one research project.U.S. Air Force - Office of Scientific Research (Contract F49620-80-C-0008

    Neurenteric cyst at the dorsal craniocervical junction in a child: Case report

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    Neurenteric cysts, also known as enterogenous cysts, are uncommon, benign, congenital lesions that usually occur in the posterior mediastinum but can be seen at any level of the neuraxis. Here, we report a pediatric patient with a neurenteric cyst in the dorsal craniocervical junction as the only third reported pediatric case in the literature in this rare location, and describe the clinical course and pathologic findings with a review of the literature on this rare entity

    Infrared Nonlinear Optics

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    Contains report on one research project.U.S. Air Force - Office of Scientific Research (Contract F49620-80-C-0008

    Early and Middle Holocene Hunter-Gatherer Occupations in Western Amazonia: The Hidden Shell Middens

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    We report on previously unknown early archaeological sites in the Bolivian lowlands, demonstrating for the first time early and middle Holocene human presence in western Amazonia. Multidisciplinary research in forest islands situated in seasonally-inundated savannahs has revealed stratified shell middens produced by human foragers as early as 10,000 years ago, making them the oldest archaeological sites in the region. The absence of stone resources and partial burial by recent alluvial sediments has meant that these kinds of deposits have, until now, remained unidentified. We conducted core sampling, archaeological excavations and an interdisciplinary study of the stratigraphy and recovered materials from three shell midden mounds. Based on multiple lines of evidence, including radiocarbon dating, sedimentary proxies (elements, steroids and black carbon), micromorphology and faunal analysis, we demonstrate the anthropogenic origin and antiquity of these sites. In a tropical and geomorphologically active landscape often considered challenging both for early human occupation and for the preservation of hunter-gatherer sites, the newly discovered shell middens provide evidence for early to middle Holocene occupation and illustrate the potential for identifying and interpreting early open-air archaeological sites in western Amazonia. The existence of early hunter-gatherer sites in the Bolivian lowlands sheds new light on the region's past and offers a new context within which the late Holocene "Earthmovers" of the Llanos de Moxos could have emerged. © 2013 Lombardo et al

    A life in progress: motion and emotion in the autobiography of Robert M. La Follette

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    This article is a study of a La Follette’s Autobiography, the autobiography of the leading Wisconsin progressive Robert M. La Follette, which was published serially in 1911 and, in book form, in 1913. Rather than focusing, as have other historians, on which parts of La Follette’s account are accurate and can therefore be trusted, it explains instead why and how this major autobiography was conceived and written. The article shows that the autobiography was the product of a sustained, complex, and often fraught series of collaborations among La Follette’s family, friends, and political allies, and in the process illuminates the importance of affective ties as well as political ambition and commitment in bringing the project to fruition. In the world of progressive reform, it argues, personal and political experiences were inseparable
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