3,252 research outputs found

    Alasdair MacIntyre as a Marxist and as a critic of Marxism

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    This essay reconstructs Alasdair MacIntyre's engagement with Marxism with a view both to illuminating the co-ordinates of his mature thought and to outlining a partial critique of that thought. While the critique of Marxism outlined in After Virtue is well known, until recently Marx's profound influence on MacIntyre was obscured by a thoroughly misleading attempt to label him as a communitarian thinker. If this erroneous interpretation of MacIntyre's mature thought is now widely discredited, the fact that he has distanced himself from several of the arguments he previously gave for rejecting Marxism both reduces the theoretical space between his mature thought and his early Marxism and highlights a consistent theme in his critique of Marxism since the 1960s to which this essay is addressed: his dissatisfaction with the ethical dimension of Marxist attempts to theorise the relationship between socialist militants and the working-class movement from below

    Launch Vehicle Operations Simulator

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    The Saturn Launch Vehicle Operations Simulator (LVOS) was developed for NASA at Kennedy Space Center. LVOS simulates the Saturn launch vehicle and its ground support equipment. The simulator was intended primarily to be used as a launch crew trainer but it is also being used for test procedure and software validation. A NASA/contractor team of engineers and programmers implemented the simulator after the Apollo XI lunar landing during the low activity periods between launches

    On Strategy and Tactics Marxism and Electoral Politics

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    The rise of Syriza and Podemos alongside debates amongst Egyptian and other socialists about participation in parliamentary elections has reignited considerable interest across the international left about the issue of parliamentary elections. It is hard to imagine a more apt moment for the publication of August Nimtz’s study of Lenin’s practical and theoretical engagement with this subject. While praising Nimtz’s scholarship, this essay challenges his interpretation of the relationship between strategy and tactics in Lenin’s thought and the position of elections therein. It concludes with an attempt to unpick what is of general significance in Lenin’s engagement with electoral politics from more local details of interest only to scholars of Russian history

    Magnetic Resonance Image Processing using Levy

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    We consider the physical nature of the self-diffusion of water molecules in tissue and explore how (Nuclear) Magnetic Resonance (MR) imaging may be used as a means of measuring the rate of diffusion in vivo. A discussion is presented on how these techniques may be implemented as a non-invasive means of assessing the response of tumours to novel therapeutics including some of the basic advantages and disadvan- tages when compared to other methods. The physical basis and mathematical models for diffusion are considered together with models for the distribution of the diffusion co- efficient including a LĂ©vy distributed model. Using a LĂ©vy distributed diffusion model, we develop a novel algorithm for the purpose of improving the signal-to-noise ratio of MR images

    Non-Gaussian Anisotropic Diffusion Processing for Medical Imagining Using the OsiriX DICOM Viewer

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    Medical imaging is a fertile area for computer graphics, image processing and real time visualization. In this paper we present a method for reducing noise in CT (Computed Tomography) and MR (Magnetic Resonance) images that (in addition to other noise sources) is characteristic of the numerical procedures required to construct the images, namely, the (inverse) Radon Transform. In both cases, MR imaging in particular, an additional noise source is due to the process of diffusion thereby predicating use of the Anisotropic Diffusion method for noise suppression. This method is based on a diffusion model for noise generation where the Diffusivity is taken to be non-isotropic (inhomogeneous) or anisotropic and is, in the absence of a priori information, computed through application of an edge detection algorithm. In this paper we extend the approach to include theeffect of fractional diffusion (when the underlying statistical model associated with the diffusion process is non-Gaussian) and derive a corresponding Finite Impulse Response Filter. The algorithms developed are implemented using the OsiriX DICOM (Digital Imaging and Communications in Medicine), a high performance open source image data visualization system for the development of processing and visualization tools

    Road user charging and implications for transport policy: Findings from the CURACAO project

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    This paper reports on the outcomes of a European project, CURACAO, designed to support the implementation of urban road user charging (URUC) as a demand management tool in urban areas. The project did this through engagement with a User Group of cities interested in pursuing URUC to identify the barriers preventing them from doing so. The project reviewed the complete process of setting up a URUC scheme from the setting of objectives, through to scheme design, predicting impacts, achieving acceptability and the implementation process and presented its findings in a State of the Art Report and a Case Studies Report. The State of the Art Report provides evidence collated from research and practice to address a series of 14 themes identified by the User Group, including objectives; scheme design; technology; business systems; prediction; traffic, environmental, economic and equity impacts; appraisal; acceptability; transferability; implementation; and evaluation. The Case Study Report reviewed 16 proposed or implemented schemes in Europe, focusing on pricing objectives, scheme design, the implementation process and scheme results. On this basis, the CURACAO Consortium developed a list of policy recommendations aimed at cities and regional authorities, national governments, and the European Commission. The paper summarises the main findings of the State of the Art Report and the case studies. On this basis, it outlines the policy recommendations which were drawn, and identifies future research needs

    Practical Materialism: Engels’s Anti-DĂŒhring as Marxist Philosophy

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    Frederick Engels’s Anti-DĂŒhring was the most important theoretical response to the emerging reformist tendencies within European socialism in the 19th century. It also proved to be Engels’s most influential, and controversial work. Because it is, as Hal Draper points out, ‘the only more or less systematic presentation of Marxism’ by either by Marx or Engels, anyone wanting to reinterpret Marx must first detach it from his seal of approval. It is thus around Anti-DĂŒhring and related texts that debates about the relationship of Marx to ‘Engelsian’ Marxism have tended to focus. This essay re-engages with debates about Engels’s mature work with a view to unpicking his contribution to Marxism from caricatured criticisms of his thought

    NMR Studies of the free Energy Landscape of Intrinsically Disordered Proteins in their free and Bound Forms

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    A Conceptual Model to Explain Dark Matter and Dark Energy

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    t This paper considers a conceptual model that attempts to explain ‘Dark Matter’ and ‘Dark Energy’. The model is based on considering a gravitational field to be the result of a mass (a Higgs field) scattering pre-existing cosmic background space-time waves or ‘Uber-waves’. The term ‘Uber’ is used to denote an outstanding or supreme example of a particular kind of gravitational wave with cosmic-scale wavelengths that are far in excess of those associated with the gravitational waves generated by accelerating masses. Such waves are taken to be the very lowest frequency components associated with the spectrum of space-time waves generated by the ‘Big Bang’ and are supported by the expanding fabric of space-time produced at the point of the big bang, i.e. the lowest frequency components of a cosmological spectrum whose bandwidth is the a Planck frequency (∌ 1043 Hz). Like electromagnetic waves, Uber waves are taken to propagate with an upper velocity consistent with the speed of light and interact with, and are scattered by, a Higgs field. This interaction produces the effect of a mass locally curving space-time, an idea that is contrary to the conventional model associated with General Relativity where mass is taken to curve space-time directly which otherwise remains ‘flat’. By assuming the pre-existence of background Uber waves, we consider the concave curvature of such waves to generate an apparent attractive gravitational force. This attractive force is taken to govern the formation of large scale structures of matter (galaxies and super-clusters of galaxies, for example) in the conventional sense but surrounded by a residual background gravitational field. It is this residual field that gives rise to the effect known as dark matter where more gravity (as an attractive only force) appears to be available than that which can be accounted for by the observed (luminous) mass, a luminosity that is generated primarily by nuclear fusion in stars. The convex curvature of Uber waves is considered to account for cosmic voids within which gravity is a repulsive force and where large scale structures of matter can therefore not be formed. This is considered to explain the super-large cosmic voids or super voids that are observed. These are regions of the universe where there is an absence of rich super clusters of matter. In these anti-gravity zones, only relatively small structures of matter can be formed by electrostatic forces alone which are then repelled from each other when their mass becomes significant enough for the force of anti-gravity to become significant. In such regions of an Uber wave, the matter generated from electrostatic forces builds up to produce a weak gravitational repulsive field due to the low mass density within a void. However, due to the immense size of these cosmic voids, they are taken to generate a net repulsive force which is considered to be the reason for the acceleration associated with the expansion of the universe; the effect of dark energy. This effect also accounts for the cosmic web structure in which luminescent matter appears to exist in relatively thin connective filaments. The purpose of this paper is to provide a conceptual model and not to investigate the ideas proposed in any significant mathematical detail. This is accomplished by building up the ideas on a case-by-case basis, coupled with a series of thought experiments but without resorting to specific physical scales or the physical parameters associated with these scales other than, by default, the speed of light and Newton’s gravitational constant

    On the Chirp Function, the Chirplet Transform and the Optimal Communication of Information

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    —The purpose of this extended paper is to provide a review of the chirp function and the chirplet transform and to investigate the application of chirplet modulation for digital communications, in particular, the transmission of binary strings. The signiïŹcance of the chirp function in the solution to a range of fundamental problems in physics is revisited to provide a background to the case and to present the context in which the chirp function plays a central role, the material presented being designed to show a variety of problems with solutions and applications that are characterized by a chirp function in a fundamental way. A study is then provided whose aim is to investigate the uniqueness of the chirp function in regard to its use for convolutionalcodinganddecoding,thelattercase(i.e.decoding) being related to the autocorrelation of the chirp function which provides a unique solution to the deconvolution problem. Complementary material in regard to the uniqueness of a chirp is addressed through an investigation into the selfcharacterizationofthechirpfunctionuponFouriertransformation. This includes a short study on the eigenfunctions of the Fourier transform, leading to a uniqueness conjecture which is based on an application of the Bluestein decomposition of a Fourier transform. The conjecture states that the chirp function is the only phase-only function to have a self-characteristic Fourier transform, and, for a speciïŹc scaling constant, a conjugate eigenfunction. In the context of this conjecture, we consider the transmission of information through a channel characterized by additive noise and the detection of signals with very low Signal-to-Noise Ratios. It is shown that application of chirplet modulation can provide a simple and optimal solution to the problem of transmitting binary strings through noisy communication channels, a result which suggests that all digital communication systems should ideally by predicated on the application of chirplet modulation. In the latter part of the paper, a method is proposed for securing the communication of information (in the form of a binary string) through chirplet modulation that is based on prime number factorization of the chirplet (angular) bandwidth. Coupled with a quantum computer for factorizing very large prime numbers using Shor’s algorithm, the method has the potential for designing a communications protocol speciïŹcally for users with access to quantum computing when the factorization of very large prime numbers is required. In thisrespect,and,intheïŹnalpartofthepaper,weinvestigatethe application of chirplet modulation for communicating through the ‘Water-Hole’. This includes the introduction of a method for distinguishing between genuine ‘intelligible’ binary strings through the Kullback-Leibler divergence which is shown to be statistically signiïŹcant for a number of natural languages
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