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Mapping Out Your Research: From Topic Selection to a Thesis Statement
Co-taught by an instruction librarian and a Writing Center coordinator, this lesson supports history students in exploring a topic and preparing for subsequent research and writing. The first and primary piece of this lesson centers on a topic speed dating activity that encourages students to look beyond the most obvious elements and narratives of their topic and seek nuance and unique perspectives through guided discussion with a peer. This is followed by a class discussion on the role that divergent thinking plays in developing a research question and some time for students to draft their own potential research question. Finally, the session concludes with a brief overview of what comes next in the research and writing process, explaining how the research question leads to a working thesis and outlining the next steps in finding sources
Analysis and Calibration of Loran-C Signals in the Lower St. Lawrence Area Using GPS
Loran-C signals along and in the Lower St. Lawrence River, namely between Québec City and the Gaspesia Peninsula on the south shore, between Québec City and Havre-Saint-Pierre on the North Shore, and between Québec City and Anticosti Island in the river, were analyzed using a mobile Loran-C coverage validation and calibration system consisting of analog and digital Loran-C receivers, differential GPS and data logging systems. The road measurements were made successively during February-March and July-August 1991 to analyse seasonal effects. The signals received from the East Coast Canada Chain (5930M, X, Y, Z) and the Northeast U.S. Chain (9960M, W, X) are discussed herein. The Field Strength and Signal to Noise Ratio measurements are compared with predicted values using various models for conductivity and atmospheric noise. The Time Difference (TD) measurements are first compared between forward and reverse runs along the road profiles to ascertain the quality and reliability of the system utilized. The differences between Winter and Summer TD measurements are then analyzed. A relatively small but significant seasonal effect is found. The GPS-derived TD distortions are compared with those derived using various models for the combined effect of the primary, secondary and additional secondary phase lags. The differences between measured and modeled distortions reaches several jis. The effect of these differences on Loran-C positions is found to reach several hundred metres in many cases. Conclusions related to the results presented herein are made, together with recommendations pertaining to the use of these results and future investigations
GPS for Marine Navigation and Hydrography
Current marine navigation and shipbome surveying accuracy requirements are reviewed. The technical characteristics of GPS are summarized and its single point positioning performance is given and compared with the above requirements. A detailed description and analysis of the three types of observables possible with GPS, namely code, carrier and Doppler frequency measurements, are presented. The following error sources are discussed: cycle slips, Selective Availability, ionospheric and tropospheric effects and multipath. A description of the various receiver measuring techniques currently available, namely C/A code LI, L2 squaring, L2 codeless, P codeless and P code, is given, together with advantages and disadvantages for marine positioning. The single and double differenced observables used in differential GPS (DGPS) mode are analysed in terms of real time versus postmission suitability. The latest techniques for quasi-instantaneous ambiguity resolution such as wide and extra wide-laning are discussed in terms of receiver requirements and operational procedures. An attempt is made at providing DGPS kinematic accuracy estimates for various cases with and without Selective Availability. Trends and prospects are forecast in the following five areas: system enhancements, user equipment, observable types and modelling, marine applications and GPS-related services
La représentation de la réalité chez Bertolt Brecht
La question de la reprĂ©sentation de la rĂ©alitĂ© est centrale aux Ă©laborations de Brecht sur le thĂ©Ăątre. Nombre de ses expĂ©rimentations artistiques ont pour but de montrer le monde social tel quâil est rĂ©ellement â en tant quâil sâagit de quelque chose dâhistorique et de transformable â aux masses qui souffrent des illusions du capitalisme moderne. Ce mĂ©moire a pour objectif dâanalyser sous divers angles le concept de rĂ©alisme tel que lâentend Brecht. Une attention particuliĂšre est portĂ©e au contexte historique, notamment aux dĂ©bats dans lesquels sâinscrivent les textes thĂ©oriques de Brecht. Le premier chapitre couvre son dĂ©bat avec LukĂĄcs et les textes thĂ©oriques sur le rĂ©alisme quâil a Ă©crits afin de se dĂ©fendre des accusations de formalisme. Comme cette dĂ©fense met surtout lâaccent sur le caractĂšre pragmatique du rĂ©alisme artistique, le deuxiĂšme chapitre vise plutĂŽt Ă explorer les conditions prĂ©alables au rĂ©alisme et comment Brecht a tentĂ© de le dĂ©ployer de façon effective au travers son thĂ©Ăątre Ă©pique. Pour y arriver, nous faisons appel aux notions de vĂ©ritĂ©, de popularitĂ© ainsi quâĂ sa critique de la tradition thĂ©Ăątrale basĂ©e sur lâidentification quâil dĂ©veloppe dans divers courts textes thĂ©oriques. Dans le dernier chapitre, la possibilitĂ© dâun rĂ©alisme selon les termes brechtiens est remise en question, notamment en sâintĂ©ressant aux critiques que lui adresse Adorno.The question of the representation of reality is central to Brecht's work on theatre. Many of his artistic experiments aim to show the social world as it really is - as something historical and transformable - to the masses who suffer from the illusions of modern capitalism. The purpose of this master's thesis is to analyze the concept of realism as understood by Brecht from various angles. Close attention has been paid to the historical context, specifically to the debates in which Brecht's theoretical texts are written. The first chapter covers his debate with Lukacs and the theoretical texts on realism that he wrote to defend himself from accusations of formalism. Since this defence emphasizes above all the pragmatic nature of artistic realism, the second chapter aims rather to explore the prerequisite for realism and how Brecht tried to effectively deploy it through his epic theatre. To achieve this, we use the notions of truth, popularity and his critique of the theatrical tradition based on the identification he develops in various short theoretical texts. In the last chapter, the possibility of realism in the Brechtian terms is questioned, in particular by taking an interest in Adorno's criticism of him
Uncovering the topology of configuration space networks
The configuration space network (CSN) of a dynamical system is an effective
approach to represent the ensemble of configurations sampled during a
simulation and their dynamic connectivity. To elucidate the connection between
the CSN topology and the underlying free-energy landscape governing the system
dynamics and thermodynamics, an analytical soluti on is provided to explain the
heavy tail of the degree distribution, neighbor co nnectivity and clustering
coefficient. This derivation allows to understand the universal CSN network
topology observed in systems ranging from a simple quadratic well to the native
state of the beta3s peptide and a 2D lattice heteropolymer. Moreover CSN are
shown to fall in the general class of complex networks describe d by the
fitness model.Comment: 6 figure
On the criticality of inferred models
Advanced inference techniques allow one to reconstruct the pattern of
interaction from high dimensional data sets. We focus here on the statistical
properties of inferred models and argue that inference procedures are likely to
yield models which are close to a phase transition. On one side, we show that
the reparameterization invariant metrics in the space of probability
distributions of these models (the Fisher Information) is directly related to
the model's susceptibility. As a result, distinguishable models tend to
accumulate close to critical points, where the susceptibility diverges in
infinite systems. On the other, this region is the one where the estimate of
inferred parameters is most stable. In order to illustrate these points, we
discuss inference of interacting point processes with application to financial
data and show that sensible choices of observation time-scales naturally yield
models which are close to criticality.Comment: 6 pages, 2 figures, version to appear in JSTA
Pom1 gradient buffering through intermolecular auto-phosphorylation.
Concentration gradients provide spatial information for tissue patterning and cell organization, and their robustness under natural fluctuations is an evolutionary advantage. In rod-shaped Schizosaccharomyces pombe cells, the DYRK-family kinase Pom1 gradients control cell division timing and placement. Upon dephosphorylation by a Tea4-phosphatase complex, Pom1 associates with the plasma membrane at cell poles, where it diffuses and detaches upon auto-phosphorylation. Here, we demonstrate that Pom1 auto-phosphorylates intermolecularly, both in vitro and in vivo, which confers robustness to the gradient. Quantitative imaging reveals this robustness through two system's properties: The Pom1 gradient amplitude is inversely correlated with its decay length and is buffered against fluctuations in Tea4 levels. A theoretical model of Pom1 gradient formation through intermolecular auto-phosphorylation predicts both properties qualitatively and quantitatively. This provides a telling example where gradient robustness through super-linear decay, a principle hypothesized a decade ago, is achieved through autocatalysis. Concentration-dependent autocatalysis may be a widely used simple feedback to buffer biological activities
Combined Acquisition and Tracking Methods for GPS L1 C/A and L1C Signals
As part of the GPS modernization, the GPS L1 C/A signal will be augmented by the L1C signal. With this improvement, for the first time, several signals from the same constellation will be available at the same frequency. In this paper, an acquisition method is implemented to combine the GPS L1 C/A and L1C signals before correlation. The combined acquisition succeeds to acquire the signal at low C/N0, whereas the acquisition of the L1C data channel alone fails. Concerning the tracking, a method to combine the GPS L1 C/A and L1C signals before the discriminator is developed. This method shows better performance than the traditional tracking using only one signal. Finally, a Kalman filter to combine the signals in the tracking is developed. It shows better performance than the traditional tracking in all conditions. Since the L1C signal will not be broadcast before 2013, these methods are tested using a software signal simulator
The Discovery of the Most Metal-Rich White Dwarf: Composition of a Tidally Disrupted Extrasolar Dwarf Planet
Cool white dwarf stars are usually found to have an outer atmosphere that is
practically pure in hydrogen or helium. However, a small fraction have traces
of heavy elements that must originate from the accretion of extrinsic material,
most probably circumstellar matter. Upon examining thousands of Sloan Digital
Sky Survey spectra, we discovered that the helium-atmosphere white dwarf SDSS
J073842.56+183509.6 shows the most severe metal pollution ever seen in the
outermost layers of such stars. We present here a quantitative analysis of this
exciting star by combining high S/N follow-up spectroscopic and photometric
observations with model atmospheres and evolutionary models. We determine the
global structural properties of our target star, as well as the abundances of
the most significant pollutants in its atmosphere, i.e., H, O, Na, Mg, Si, Ca,
and Fe. The relative abundances of these elements imply that the source of the
accreted material has a composition similar to that of Bulk Earth. We also
report the signature of a circumstellar disk revealed through a large infrared
excess in JHK photometry. Combined with our inferred estimate of the mass of
the accreted material, this strongly suggests that we are witnessing the
remains of a tidally disrupted extrasolar body that was as large as Ceres.Comment: 7 pages in emulateapj, 5 figures, accepted for publication in Ap
Turnover, account value and diversification of real traders: evidence of collective portfolio optimizing behavior
Despite the availability of very detailed data on financial market,
agent-based modeling is hindered by the lack of information about real trader
behavior. This makes it impossible to validate agent-based models, which are
thus reverse-engineering attempts. This work is a contribution to the building
of a set of stylized facts about the traders themselves. Using the client
database of Swissquote Bank SA, the largest on-line Swiss broker, we find
empirical relationships between turnover, account values and the number of
assets in which a trader is invested. A theory based on simple mean-variance
portfolio optimization that crucially includes variable transaction costs is
able to reproduce faithfully the observed behaviors. We finally argue that our
results bring into light the collective ability of a population to construct a
mean-variance portfolio that takes into account the structure of transaction
costsComment: 26 pages, 9 figures, Fig. 8 fixe
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