2,529 research outputs found

    Confidence regions for variance ratios in variance components models

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    Statistical mechanics for constructing confidence intervals for variance ratios in balanced and unbalanced experimental design

    Stochastic compartmental analysis - Some applications and examples of estimation in a pulse labelled system

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    Stochastic compartmental analysis with examples of estimation in pulse labelled syste

    A computer program for the mixed analysis of variance model based on maximum likelihood

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    Computer program for mixed analysis of variance model based on maximum likelihoo

    A 3D Face Modelling Approach for Pose-Invariant Face Recognition in a Human-Robot Environment

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    Face analysis techniques have become a crucial component of human-machine interaction in the fields of assistive and humanoid robotics. However, the variations in head-pose that arise naturally in these environments are still a great challenge. In this paper, we present a real-time capable 3D face modelling framework for 2D in-the-wild images that is applicable for robotics. The fitting of the 3D Morphable Model is based exclusively on automatically detected landmarks. After fitting, the face can be corrected in pose and transformed back to a frontal 2D representation that is more suitable for face recognition. We conduct face recognition experiments with non-frontal images from the MUCT database and uncontrolled, in the wild images from the PaSC database, the most challenging face recognition database to date, showing an improved performance. Finally, we present our SCITOS G5 robot system, which incorporates our framework as a means of image pre-processing for face analysis

    A Proposed Comparison of Fall Roadside Pheasant Counts and Flushing Rates

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    Although the fall roadside pheasant census (Bennett and Hendrickson, 1938) has reflected the fall pheasant population from an administrative standpoint for the past 17 years within the primary range in Iowa (Kozicky, et al., 1952), there still exist the problems of correlating these roadside counts to actual populations or flushing rates. Inasmuch as we do not have any known method of obtaining exact numbers of birds for a given ·section of land at the present time, we cannot develop a method of interpreting the roadside count as reflecting a mean number of birds per acre in the primary pheasant range within a, specified confidence limits. However, it may be possible to relate the index obtained from the roadside count to birds flushed per hour on a section of land. The evaluation would be of assistance to administrators and sportsmen alike. The sportsmen are interested in knowing just how many birds they can expect to flush in an hour of hunting, based on roadside counts, and the administrator would like confirmation on the correlation, if any, between the roadside count and flushing rates

    Implementation of a combined association-linkage model for quantitative traits in linear mixed model procedures of statistical packages

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    Atransmission disequilibrium test for quantitative traits which combines association and linkage analyses is currently available in several dedicated software packages. We describe how to implement such models in linear mixed model procedures that are available in widely used statistical packages such as SPSS. We also briefly mention a few extensions of the model that become naturally available once the model is implemented in such procedures. Genotyping of many microsatellite markers or single nucleotide polymorphisms (SNPs) over the entire genome is becoming increasingly common in human genetics. In those high-resolution maps the average distance between microsatellite markers may be as small as 5 cM and between SNPs one half cM or less. At those small distances it becomes fairly likely that some markers in the set are in linkage disequilibrium (LD) with a gene affecting the trait (a so-called quantitative trait locus or QTL if the trait or the vulnerability distribution is quantitative). Different alleles or combinations of alleles of the markers or SNPs can then be associated with different trait means. Association studies are conducted to discover such allelic effects. Abecasis et al. (2000) generalized the model proposed by Fulker et al. (1999) for combined linkage and association tests, within and between families. The Fulker-Abecasis or F-A model is implemented in the program QTD

    A pp-adic RanSaC algorithm for stereo vision using Hensel lifting

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    A pp-adic variation of the Ran(dom) Sa(mple) C(onsensus) method for solving the relative pose problem in stereo vision is developped. From two 2-adically encoded images a random sample of five pairs of corresponding points is taken, and the equations for the essential matrix are solved by lifting solutions modulo 2 to the 2-adic integers. A recently devised pp-adic hierarchical classification algorithm imitating the known LBG quantisation method classifies the solutions for all the samples after having determined the number of clusters using the known intra-inter validity of clusterings. In the successful case, a cluster ranking will determine the cluster containing a 2-adic approximation to the "true" solution of the problem.Comment: 15 pages; typos removed, abstract changed, computation error remove

    Long-range pollution transport during the MILAGRO-2006 campaign: a case study of a major Mexico City outflow event using free-floating altitude-controlled balloons

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    One of the major objectives of the Megacities Initiative: Local And Global Research Observations (MILAGRO-2006) campaign was to investigate the long-range transport of polluted Mexico City Metropolitan Area (MCMA) outflow and determine its downwind impacts on air quality and climate. Six research aircraft, including the National Center for Atmospheric Research (NCAR) C-130, made extensive chemical, aerosol, and radiation measurements above MCMA and more than 1000 km downwind in order to characterize the evolution of the outflow as it aged and dispersed over the Mesa Alta, Sierra Madre Oriental, Coastal Plain, and Gulf of Mexico. As part of this effort, free-floating Controlled-Meteorological (CMET) balloons, commanded to change altitude via satellite, made repeated profile measurements of winds and state variables within the advecting outflow. In this paper, we present an analysis of the data from two CMET balloons that were launched near Mexico City on the afternoon of 18 March 2006 and floated downwind with the MCMA pollution for nearly 30 h. The repeating profile measurements show the evolving structure of the outflow in considerable detail: its stability and stratification, interaction with other air masses, mixing episodes, and dispersion into the regional background. Air parcel trajectories, computed directly from the balloon wind profiles, show three transport pathways on 18–19 March: (a) high-altitude advection of the top of the MCMA mixed layer, (b) mid-level outflow over the Sierra Madre Oriental followed by decoupling and isolated transport over the Gulf of Mexico, and (c) low-level outflow with entrainment into a cleaner northwesterly jet above the Coastal Plain. The C-130 aircraft intercepted the balloon-based trajectories three times on 19 March, once along each of these pathways; in all three cases, peaks in urban tracer concentrations and LIDAR backscatter are consistent with MCMA pollution. In comparison with the transport models used in the campaign, the balloon-based trajectories appear to shear the outflow far more uniformly and decouple it from the surface, thus forming a thin but expansive polluted layer over the Gulf of Mexico that is well aligned with the aircraft observations. These results provide critical context for the extensive aircraft measurements made during the 18–19 March MCMA outflow event and may have broader implications for modelling and understanding long-range transport

    Banking from Leeds, not London: regional strategy and structure at the Yorkshire Bank, 1859–1952

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    Industrial philanthropist Edward Akroyd created the Yorkshire Penny Savings Bank in 1859. Despite competition from the Post Office Savings Bank after 1861 and a serious reserve problem in 1911, it sustained his overall strategy to become a successful regional bank. Using archival and contemporary sources to build on recent scholarship illustrating how savings banks were integrated into local economies and the complementary roles of philanthropy and paternalism, we analyse an English regional bank's strategy, including an assessment of strategic innovation, ownership changes and management structure. This will demonstrate that the founder's vision continued, even though the 1911 crisis radically altered both strategy and structure

    The Absolute Line Quadric and Camera Autocalibration

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    We introduce a geometrical object providing the same information as the absolute conic: the absolute line quadric (ALQ). After the introduction of the necessary exterior algebra and Grassmannian geometry tools, we analyze the Grassmannian of lines of P^3 from both the projective and Euclidean points of view. The exterior algebra setting allows then to introduce the ALQ as a quadric arising very naturally from the dual absolute quadric. We fully characterize the ALQ and provide clean relationships to solve the inverse problem, i.e., recovering the Euclidean structure of space from the ALQ. Finally we show how the ALQ turns out to be particularly suitable to address the Euclidean autocalibration of a set of cameras with square pixels and otherwise varying intrinsic parameters, providing new linear and non-linear algorithms for this problem. We also provide experimental results showing the good performance of the techniques
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