2,699 research outputs found

    Clubs, parties, factions

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    Historical debate over the political clubs of the French Revolution over the past two centuries has turned on the question of whether factionalism grew out of their democratic principles or from external circumstances. This chapter suggests that neither ideology nor circumstances can fully account for this radicalization. Instead, the conditions of a ‘weak state’ must be addressed. When authorities were unable or unwilling to implement legislation or to respond to demands coming from society, the clubs often intervened, militating for action to be taken. Tax collection and the crisis of subsistence constituted two crucial issues that the state failed to managed. The clubs, which were divided on these issues, found themselves debating them in a context in which no legal limits on slander (another state weakness) existed. Unchecked calumny poisoned intra and inter-club relations and contributed to factionalism

    Capitalism's alter ego : the birth of reciprocity in eighteenth-century France

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    This article traces the concept of reciprocity from its emergence in French philosophy during the Enlightenment to its recent growth in the humanities and social sciences. After charting the term’s accelerated use in French and English in the modern period, the article shows how its meaning has continually wavered between exchange equivalence (barter) and generosity and obligation (the gift, the Golden Rule). During the Enlightenment, these meanings converged in efforts to naturalize commerce and justify liberal economic reforms. A free-market society, it was argued, would be fair and bountiful. Upon the failure of such reforms in the early French Revolution, reciprocity and its new synonym “fraternity” became detached from economic liberalism. As capitalism became increasingly associated with wealth inequality in the nineteenth century, reciprocity became the watchword of capitalism’s critics, who tried to conceptualize social bonds in terms other than those offered by Homo economicus

    Engineering calculations for communications satellite systems planning

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    A procedure is described that was used to calculate minimum required satellite separations based on total link carrier to interference requirements. Also summarized are recent results with a switching algorithm for satellite synthesis problems. Analytic solution value bounds for two of the satellite synthesis models studied are described. Preliminary results from an empirical study of alternate mixed integer programming models for satellite synthesis are presented. Research plans for the near future are discussed

    The Informal Logic of Mathematical Proof

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    Informal logic is a method of argument analysis which is complementary to that of formal logic, providing for the pragmatic treatment of features of argumentation which cannot be reduced to logical form. The central claim of this paper is that a more nuanced understanding of mathematical proof and discovery may be achieved by paying attention to the aspects of mathematical argumentation which can be captured by informal, rather than formal, logic. Two accounts of argumentation are considered: the pioneering work of Stephen Toulmin [The uses of argument, Cambridge University Press, 1958] and the more recent studies of Douglas Walton, [e.g. The new dialectic: Conversational contexts of argument, University of Toronto Press, 1998]. The focus of both of these approaches has largely been restricted to natural language argumentation. However, Walton's method in particular provides a fruitful analysis of mathematical proof. He offers a contextual account of argumentational strategies, distinguishing a variety of different types of dialogue in which arguments may occur. This analysis represents many different fallacious or otherwise illicit arguments as the deployment of strategies which are sometimes admissible in contexts in which they are inadmissible. I argue that mathematical proofs are deployed in a greater variety of types of dialogue than has commonly been assumed. I proceed to show that many of the important philosophical and pedagogical problems of mathematical proof arise from a failure to make explicit the type of dialogue in which the proof is introduced.Comment: 14 pages, 1 figure, 3 tables. Forthcoming in Perspectives on Mathematical Practices: Proceedings of the Brussels PMP2002 Conference (Logic, Epistemology and the Unity of the Sciences Series), J. P. Van Bendegem & B. Van Kerkhove, edd. (Dordrecht: Kluwer, 2004

    Green construction in India: gaining a deeper understanding

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    A workshop on green construction was organized in New Delhi in July 2008 by Jamia Millia University, India and University of Salford, U.K., aiming to increase 'green' practices that are environmentally friendly and energy efficient. The workshop included participants from regulatory bodies, public and private construction companies and researchers. The object of the workshop was to provide an opportunity to capture issues, challenges and research issues in green practices throughout the supply chain in the construction sector in India. The methodology constituted a survey that was provided to all participants, where eight questions were composed by the facilitators. The participants were asked about their views on voluntary and compulsory ways of assessment and audit of green implementation in India. The findings of the workshop featured major challenges, drivers, initiatives, and the ways of effective implementation as well as enforcement on the discussed topic

    Application of heuristic satellite plan synthesis algorithms to requirements of the WARC-88 allotment plan

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    Creation of an Allotment Plan for the Fixed Satellite Service at the 1988 Space World Administrative Radio Conference (WARC) represented a complex satellite plan synthesis problem, involving a large number of planned and existing systems. Solutions to this problem at WARC-88 required the use of both automated and manual procedures to develop an acceptable set of system positions. Development of an Allotment Plan may also be attempted through solution of an optimization problem, known as the Satellite Location Problem (SLP). Three automated heuristic procedures, developed specifically to solve SLP, are presented. The heuristics are then applied to two specific WARC-88 scenarios. Solutions resulting from the fully automated heuristics are then compared with solutions obtained at WARC-88 through a combination of both automated and manual planning efforts

    Frequency Domain Functional Near-Infrared Spectrometer (fNIRS) for Crew State Monitoring

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    A frequency domain functional near-infrared spectrometer (fNIRS) and accompanying software have been developed by the NASA Glenn Research Center as part of the Airspace Operations and Safety Program (AOSP) Technologies for Airplane State Awareness (TASA)SE211 Crew State Monitoring (CSM) Project. The goal of CSM was to develop a suite of instruments to measure the cognitive state of operators while performing operational activities. The fNIRS was one of the instruments intended for the CSM, developed to measure changes in oxygen levels in the brain noninvasively

    A low-luminosity soft state in the short period black hole X-ray binary Swift J1753.5-0127

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    We present results from the spectral fitting of the candidate black hole X-ray binary Swift J1753.5-0127 in an accretion state previously unseen in this source. We fit the 0.7-78 keV spectrum with a number of models, however the preferred model is one of a multi-temperature disk with an inner disk temperature kTin=0.252±0.003\mathrm{k}T_\mathrm{in}=0.252\pm0.003 keV scattered into a steep power-law with photon index Γ=6.390.02+0.08\Gamma=6.39^{+0.08}_{-0.02} and an additional hard power law tail (Γ=1.79±0.02\Gamma=1.79\pm0.02). We report on the emergence of a strong disk-dominated component in the X-ray spectrum and we conclude that the source has entered the soft state for the first time in its ~10 year prolonged outburst. Using reasonable estimates for the distance to the source (33 kpc) and black hole mass (5M5M_{\odot}), we find the unabsorbed luminosity (0.1-100 keV) to be 0.60\approx0.60% of the Eddington luminosity, making this one of the lowest luminosity soft states recorded in X-ray binaries. We also find that the accretion disk extended towards the compact object during its transition from hard to soft, with the inner radius estimated to be Rin=28.00.4+0.7RgR_{\mathrm{in}}=28.0^{+0.7}_{-0.4} R_g or ~12Rg12R_g, dependent on the boundary condition chosen, assuming the above distance and mass, a spectral hardening factor f=1.7f=1.7 and a binary inclination i=55i=55^{\circ}.Comment: 10 pages, 5 figures, accepted for publication in MNRA

    A NuSTAR observation of the reflection spectrum of the low mass X-ray binary 4U 1728-34

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    We report on a simultaneous NuSTAR and Swift observation of the neutron star low-mass X-ray binary 4U 1728-34. We identified and removed four Type I X-ray bursts during the observation in order to study the persistent emission. The continuum spectrum is hard and well described by a black body with kT=kT= 1.5 keV and a cutoff power law with Γ=\Gamma= 1.5 and a cutoff temperature of 25 keV. Residuals between 6 and 8 keV provide strong evidence of a broad Fe Kα\alpha line. By modeling the spectrum with a relativistically blurred reflection model, we find an upper limit for the inner disk radius of Rin2RISCOR_{\rm in}\leq2 R_{\rm ISCO}. Consequently we find that RNS23R_{\rm NS}\leq23 km, assuming M=1.4{\mbox{\rm\,M_{\mathord\odot}}} and a=0.15a=0.15. We also find an upper limit on the magnetic field of B2×108B\leq2\times10^8 G.Comment: 9 pages, 8 figure

    The smooth cyclotron line in Her X-1 as seen with NuSTAR

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    Her X-1, one of the brightest and best studied X-ray binaries, shows a cyclotron resonant scattering feature (CRSF) near 37 keV. This makes it an ideal target for detailed study with the Nuclear Spectroscopic Telescope Array (NuSTAR), taking advantage of its excellent hard X-ray spectral resolution. We observed Her X-1 three times, coordinated with Suzaku, during one of the high flux intervals of its 35d super-orbital period. This paper focuses on the shape and evolution of the hard X-ray spectrum. The broad-band spectra can be fitted with a powerlaw with a high-energy cutoff, an iron line, and a CRSF. We find that the CRSF has a very smooth and symmetric shape, in all observations and at all pulse-phases. We compare the residuals of a line with a Gaussian optical depth profile to a Lorentzian optical depth profile and find no significant differences, strongly constraining the very smooth shape of the line. Even though the line energy changes dramatically with pulse phase, we find that its smooth shape does not. Additionally, our data show that the continuum is only changing marginally between the three observations. These changes can be explained with varying amounts of Thomson scattering in the hot corona of the accretion disk. The average, luminosity-corrected CRSF energy is lower than in past observations and follows a secular decline. The excellent data quality of NuSTAR provides the best constraint on the CRSF energy to date.Comment: 13 pages, 13 figures, accepted for publication in Ap
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