25,898 research outputs found

    Validation of a new flying quality criterion for the landing task

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    A strong correlation has been found to exist between flight path angle peak overshoot and pilot ratings for the landing task. The use of flightpath overshoot as a flying quality metric for landing is validated by correlation with four different in-flight simulation programs and a ground simulation study. Configurations tested were primarily medium-weight generic transports. As a result of good correlation with this extensive data base, criterion boundaries are proposed for landing based on the flight path peak overshoot metric

    Strong Evidence of Normal Heat Conduction in a one-Dimensional Quantum System

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    We investigate how the normal energy transport is realized in one-dimensional quantum systems using a quantum spin system. The direct investigation of local energy distribution under thermal gradient is made using the quantum master equation, and the mixing properties and the convergence of the Green-Kubo formula are investigated when the number of spin increases. We find that the autocorrelation function in the Green-Kubo formula decays as t1.5\sim t^{-1.5} to a finite value which vanishes rapidly with the increase of the system size. As a result, the Green-Kubo formula converges to a finite value in the thermodynamic limit. These facts strongly support the realization of Fourier heat law in a quantum system.Comment: 7 pages 6 figure

    Theory of 2δ\delta-kicked Quantum Rotors

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    We examine the quantum dynamics of cold atoms subjected to {\em pairs} of closely spaced δ\delta-kicks from standing waves of light, and find behaviour quite unlike the well-studied quantum kicked rotor (QKR). Recent experiments [Jones et al, {\em Phys. Rev. Lett. {\bf 93}, 223002 (2004)}] identified a regime of chaotic, anomalous classical diffusion. We show that the corresponding quantum phase-space has a cellular structure, arising from a unitary matrix with oscillating band-width. The corresponding eigenstates are exponentially localized, but scale with a fractional power, L0.75L \sim \hbar^{-0.75}, in contrast to the QKR for which L1L \sim \hbar^{-1}. The effect of inter-cell (and intra-cell) transport is investigated by studying the spectral fluctuations with both periodic as well as `open' boundary conditions.Comment: 12 pages with 14 figure

    Hierarchical ResNeXt Models for Breast Cancer Histology Image Classification

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    Microscopic histology image analysis is a cornerstone in early detection of breast cancer. However these images are very large and manual analysis is error prone and very time consuming. Thus automating this process is in high demand. We proposed a hierarchical system of convolutional neural networks (CNN) that classifies automatically patches of these images into four pathologies: normal, benign, in situ carcinoma and invasive carcinoma. We evaluated our system on the BACH challenge dataset of image-wise classification and a small dataset that we used to extend it. Using a train/test split of 75%/25%, we achieved an accuracy rate of 0.99 on the test split for the BACH dataset and 0.96 on that of the extension. On the test of the BACH challenge, we've reached an accuracy of 0.81 which rank us to the 8th out of 51 teams

    The Theory of Caustics and Wavefront Singularities with Physical Applications

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    This is intended as an introduction to and review of the work of V, Arnold and his collaborators on the theory of Lagrangian and Legendrian submanifolds and their associated maps. The theory is illustrated by applications to Hamilton-Jacobi theory and the eikonal equation, with an emphasis on null surfaces and wavefronts and their associated caustics and singularities.Comment: Figs. not include

    Dephasing in matter-wave interferometry

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    We review different attempts to show the decoherence process in double-slit-like experiments both for charged particles (electrons) and neutral particles with permanent dipole moments. Interference is studied when electrons or atomic systems are coupled to classical or quantum electromagnetic fields. The interaction between the particles and time-dependent fields induces a time-varying Aharonov phase. Averaging over the phase generates a suppression of fringe visibility in the interference pattern. We show that, for suitable experimental conditions, the loss of contrast for dipoles can be almost as large as the corresponding one for coherent electrons and therefore, be observed. We analyze different trajectories in order to show the dependence of the decoherence factor with the velocity of the particles.Comment: 9 pages, 1 eps-figure. To appear in J. Phys. A: Math. Ge

    Discussion paper: A new distributed infrastructure and services market

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    This discussion paper was completed with the support of the Australian Council for Infrastructure Development (AusCID). It seeks to build the case, firstly, for change towards more distributed (or decentralised) infrastructure and service provision; secondly, for private sector involvement in that change; and thirdly for thinking about it from an industry perspective in terms of a new and very different market with a wealth of different opportunities. We are working to form a partnership between AusCID, ISF and other stakeholders to take the analysis to the next level and help to realise the opportunities identified. This work could involve assessing the nature and potential size of the market in distributed infrastructure and services, identifying and evaluating the opportunities within it, understanding the barriers and challenges in creating it and outlining some possible strategies to overcome those barriers. Three key drivers are helping to create new opportunities and a market in distributed infrastructure and services which looks very different to the traditional infrastructure market. We have defined this Distributed Infrastructure and Services (DIS) market as one involving products and services that: - increase efficiency and conservation - provide distributed and decentralised supply - involve change to the system as a whole These can be complementary to the existing infrastructure industry as well as offering new and very different opportunities. To help make the DIS opportunities a reality, we identified a need to understand the change and its potential from an industry perspective. We have started to do so in this discussion paper by examining the case for change in five categories: - the growth market - product and service opportunities - competitor development and opportunity - policy and economic incentives - existing business improvemen

    Calculation of the Aharonov-Bohm wave function

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    A calculation of the Aharonov-Bohm wave function is presented. The result is a series of confluent hypergeometric functions which is finite at the forward direction.Comment: 12 pages in LaTeX, and 3 PostScript figure
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