989 resultados para Radio science
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A dissertação comenta criticamente as interpretações recentes referentes ao vitalismo no século XVIII, dedicando atenção especial aos Nouveuax Éléments de la Science de lHomme (publicado primeiramente em 1778), de Paul-Joseph Barthez (1734-1806). Até a segunda metade do século XX, como é primeiramente argumentado nesta dissertação, intérpretes do iluminismo entendiam a doutrina mecanicista como a herdeira direta da Revolução Científica, bem como a corrente dominante no mundo das ciências da vida ao longo de todo o século XVIII. Assim, na historiografia do século passado, o vitalismo era ou escassamente mencionado, ou visto como uma retrógrada corrente anti-iluminista. Mais recentemente, vários historiadores e pesquisadores da história das ciências no século XVIII (sobretudo Williams e Reill) entendem o iluminismo de um modo mais amplo e plural, considerando o vitalismo iluminista (um termo proposto por Reill) como parte integrante de um conceito mais dinâmico de iluminismo. A seguir, são apresentados a doutrina mecanicista e seus conceitos centrais, bem como as ideias de alguns dos principais representantes do mecanicismo no século XVII e início do XVIII, no caso, mais especificamente, do mecanicismo newtoniano. Em seguida, são expostos e comentados a doutrina vitalista e seus conceitos, no que é dado destaque ao vitalismo na Universidade de Montpellier. Nesse contexto, são comentados conceitos vitalistas, tal como apresentados nos Nouveuax Éléments de la Science de lHomme, no qual Barthez propõe uma nova fisiologia baseada no princípio vital; nisso são apresentados sua metodologia de pesquisa, o conceito de princípio vital, as forças sensitivas e motrizes do princípio da vida, além dos conceitos de simpatia, sinergia e, por fim, o conceito de temperamento. Esses conceitos ou essa terminologia , tal como é mostrado, não são originalmente concebidos por Barthez, mas foram por ele reapropriados e reformulados em debate com o newtonianismo e demais correntes filosóficas médicas desde a Antiguidade até o século XVIII, assim como com observações e experimentos próprios às investigações médico-científicas da época. Como resultado, é alcançada uma compreensão da doutrina vitalista como um esforço intelectual inovador tanto interagindo quanto integrado com o debate científico contemporâneo, ou seja, os médicos vitalistas se viam e, em geral, eram vistos como atuando segundo os padrões de cientificidade exigidos por seus pares.
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This article introduces a new listing of published scientific contributions from the Freshwater Biological Association (FBA) and its later Research Council associates – the Institute of Freshwater Ecology (1989–2000) and the Centre for Ecology and Hydrology (2000+). The period 1929–2006 is covered. The authors offer also information on specific features of the listing; also an outline of influences that underlay the research, and its scientific scope.
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While synoptic surveys in the optical and at high energies have revealed a rich discovery phase space of slow transients, a similar yield is still awaited in the radio. Majority of the past blind surveys, carried out with radio interferometers, have suffered from a low yield of slow transients, ambiguous transient classifications, and contamination by false positives. The newly-refurbished Karl G. Jansky Array (Jansky VLA) offers wider bandwidths for accurate RFI excision as well as substantially-improved sensitivity and survey speed compared with the old VLA. The Jansky VLA thus eliminates the pitfalls of interferometric transient search by facilitating sensitive, wide-field, and near-real-time radio surveys and enabling a systematic exploration of the dynamic radio sky. This thesis aims at carrying out blind Jansky VLA surveys for characterizing the radio variable and transient sources at frequencies of a few GHz and on timescales between days and years. Through joint radio and optical surveys, the thesis addresses outstanding questions pertaining to the rates of slow radio transients (e.g. radio supernovae, tidal disruption events, binary neutron star mergers, stellar flares, etc.), the false-positive foreground relevant for the radio and optical counterpart searches of gravitational wave sources, and the beaming factor of gamma-ray bursts. The need for rapid processing of the Jansky VLA data and near-real-time radio transient search has enabled the development of state-of-the-art software infrastructure. This thesis has successfully demonstrated the Jansky VLA as a powerful transient search instrument, and it serves as a pathfinder for the transient surveys planned for the SKA-mid pathfinder facilities, viz. ASKAP, MeerKAT, and WSRT/Apertif.
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A substantial amount of important scientific information is contained within astronomical data at the submillimeter and far-infrared (FIR) wavelengths, including information regarding dusty galaxies, galaxy clusters, and star-forming regions; however, these wavelengths are among the least-explored fields in astronomy because of the technological difficulties involved in such research. Over the past 20 years, considerable efforts have been devoted to developing submillimeter- and millimeter-wavelength astronomical instruments and telescopes.
The number of detectors is an important property of such instruments and is the subject of the current study. Future telescopes will require as many as hundreds of thousands of detectors to meet the necessary requirements in terms of the field of view, scan speed, and resolution. A large pixel count is one benefit of the development of multiplexable detectors that use kinetic inductance detector (KID) technology.
This dissertation presents the development of a KID-based instrument including a portion of the millimeter-wave bandpass filters and all aspects of the readout electronics, which together enabled one of the largest detector counts achieved to date in submillimeter-/millimeter-wavelength imaging arrays: a total of 2304 detectors. The work presented in this dissertation has been implemented in the MUltiwavelength Submillimeter Inductance Camera (MUSIC), a new instrument for the Caltech Submillimeter Observatory (CSO).
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The intent of this study is to provide formal apparatus which facilitates the investigation of problems in the methodology of science. The introduction contains several examples of such problems and motivates the subsequent formalism.
A general definition of a formal language is presented, and this definition is used to characterize an individual’s view of the world around him. A notion of empirical observation is developed which is independent of language. The interplay of formal language and observation is taken as the central theme. The process of science is conceived as the finding of that formal language that best expresses the available experimental evidence.
To characterize the manner in which a formal language imposes structure on its universe of discourse, the fundamental concepts of elements and states of a formal language are introduced. Using these, the notion of a basis for a formal language is developed as a collection of minimal states distinguishable within the language. The relation of these concepts to those of model theory is discussed.
An a priori probability defined on sets of observations is postulated as a reflection of an individual’s ontology. This probability, in conjunction with a formal language and a basis for that language, induces a subjective probability describing an individual’s conceptual view of admissible configurations of the universe. As a function of this subjective probability, and consequently of language, a measure of the informativeness of empirical observations is introduced and is shown to be intuitively plausible – particularly in the case of scientific experimentation.
The developed formalism is then systematically applied to the general problems presented in the introduction. The relationship of scientific theories to empirical observations is discussed and the need for certain tacit, unstatable knowledge is shown to be necessary to fully comprehend the meaning of realistic theories. The idea that many common concepts can be specified only by drawing on knowledge obtained from an infinite number of observations is presented, and the problems of reductionism are examined in this context.
A definition of when one formal language can be considered to be more expressive than another is presented, and the change in the informativeness of an observation as language changes is investigated. In this regard it is shown that the information inherent in an observation may decrease for a more expressive language.
The general problem of induction and its relation to the scientific method are discussed. Two hypotheses concerning an individual’s selection of an optimal language for a particular domain of discourse are presented and specific examples from the introduction are examined.
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A review article looking at the type of information requirements commonly shared by scientists and their use of traditional information services. Areas covered include primary requirements of IFE (Institute of Freshwater Ecology) staff, pure versus applied research, informal and personal sources of information, and traditional library and information services. It goes on to describe how research into information systems and technology may improve the wider accessibility and use of information to the scientific community. Technologies covered include online databases, telecommunications, gateways, expert systems, optical technology and applications of CDROM.
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Science Cafes present a casual meeting place where people who may have little or no science background can learn about a current scientific topic in an informal and friendly environment. The coffee shop setting is designed to be inviting and informal so that students, faculty, and community members can feel comfortable and engage in lively and meaningful conversations. The café is organized around an interesting scientific topic with a brief presentation by a scientist and may include a short video clip. A Science Café can (1) provide an opportunity and venue for increasing science literacy, (2) publicize local scientific endeavors, and (3) identify the library as an epicenter of informal education on the campus and in the community. This presentation will describe the development of the Science Café at the University of Southern Mississippi Gulf Coast campus Library in Long Beach and plans for future cafes on the Mississippi coast.
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The first concept of a new library was introduced in 2001 by a faculty member at the University of Texas Marine Science Institute. The suggestion for the construction of a new library was based on two specific reasons: existing library is located in one of the most vulnerable buildings to hurricane damage and the library has outgrown its current space. This presentation provides a general overview of the current status and changing needs of the Marine Science Library and how the idea of a new library finally became a reality
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337 p.
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A new listing of published scientific contributions from the Freshwater Biological Association (FBA) and its later Research Council associates – the Institute of Freshwater Ecology (1989–2000) and the Centre for Ecology and Hydrology (2000+) is provided. The period 1929–2006 is covered. The compilation extends an earlier list assembled by in 1979.
Resumo:
A menudo, el deslumbramiento de los nuevos medios impide el reconocimiento debido a otras alternativas de comunicación social que, de manera persistente y discreta, han llegado a confundirse con nuestra propia vida. Es el caso de este medio invisible, que bien se merecía un congreso dedicado a la mejor radio y a uno de sus mayores inspiradores, Bertolt Brecht, quien ochenta años atrás imaginó una radio interactiva cuando no existía la tecnología necesaria para hacer realidad su sueño. Hoy como ayer, las voces comunicantes de la radio cuentan mil y una historias que los oyentes siguen como si les fuera la vida en ello. Quizá la radio no esté a la cabeza de las industrias creativas, pero su magia sigue desatando la imaginación y la creatividad de las audiencias. Es por eso, y por su cercanía, que da tanta confianza y es tan querida. Nada más lejos de nuestra intención que la autocomplacencia, un virus tanto o más peligroso que el ruido y la cacofonía radiofónica, que de todo hay en el dial. Los participantes en este encuentro nos hemos conjurado a favor de una radio abierta; hecha con cabeza y corazón, como la vida misma; y más acogedora con los jóvenes creadores, que no lo saben todo de la radio, pero, por eso mismo, están mejor preparados para llevar el ritmo que bailan las neuronas de las nuevas audiencias. Una radio que da la palabra a la gente, sabe escuchar, y no se agota en el ejercicio inútil de escucharse a sí misma.
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One of the most challenging problems in mobile broadband networks is how to assign the available radio resources among the different mobile users. Traditionally, research proposals are either speci c to some type of traffic or deal with computationally intensive algorithms aimed at optimizing the delivery of general purpose traffic. Consequently, commercial networks do not incorporate these mechanisms due to the limited hardware resources at the mobile edge. Emerging 5G architectures introduce cloud computing principles to add flexible computational resources to Radio Access Networks. This paper makes use of the Mobile Edge Computing concepts to introduce a new element, denoted as Mobile Edge Scheduler, aimed at minimizing the mean delay of general traffic flows in the LTE downlink. This element runs close to the eNodeB element and implements a novel flow-aware and channel-aware scheduling policy in order to accommodate the transmissions to the available channel quality of end users.
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En este documento se recoge toda la documentación asociada al desarrollo de la aplicación para dispositivos móviles Firefox OS, FM Radio RDS. La experiencia ha sido muy satisfactoria, a pesar de las frustraciones pasadas. Se han conseguido cumplir todos los objetivos establecidos inicialmente, obteniendo como resultado una aplicación muy cercana a la ideada. Se puede considerar una herramienta útil y novedosa para la reproducción de la radio FM en función de la posición en los dispositivos con el sistema operativo móvil Firefox OS. Se tiene previsto añadir futuras mejoras, como darle un enfoque más social. Personalmente, se han logrado alcanzar habilidades en el desarrollo de aplicaciones web que me permitirán realizar otros proyectos futuros. A pesar de no haber cumplido con los plazos establecidos en la planificación principal, la sensación personal es positiva al haber conseguido realizar un trabajo de tal magnitud por cuenta propia.
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This report is an introduction to the concept of treewidth, a property of graphs that has important implications in algorithms. Some basic concepts of graph theory are presented in the first chapter for those readers that are not familiar with the notation. In Chapter 2, the definition of treewidth and some different ways of characterizing it are explained. The last two chapters focus on the algorithmic implications of treewidth, which are very relevant in Computer Science. An algorithm to compute the treewidth of a graph is presented and its result can be later applied to many other problems in graph theory, like those introduced in the last chapter.