33 research outputs found
A tabu search approach for the reconstruction of binary images without empty interior region
In this paper, we are concerned with a discrete tomography problem. We seek to reconstruct a binary image from its orthogonal projections, i.e, its horizontal and vertical line sums without interior black holes. We provide a tabu search approach to minimize the number of holes while satisfying the projections. We test our approach on some random binary images. Computational results show that the algorithm proposed produces near-optimal solutions for all test problems
Common variation in PHACTR1 is associated with susceptibility to cervical artery dissection
Cervical artery dissection (CeAD), a mural hematoma in a carotid or vertebral artery, is a major cause of ischemic stroke in young adults although relatively uncommon in the general population (incidence of 2.6/100,000 per year). Minor cervical traumas, infection, migraine and hypertension are putative risk factors, and inverse associations with obesity and hypercholesterolemia are described. No confirmed genetic susceptibility factors have been identified using candidate gene approaches. We performed genome-wide association studies (GWAS) in 1,393 CeAD cases and 14,416 controls. The rs9349379[G] allele (PHACTR1) was associated with lower CeAD risk (odds ratio (OR) = 0.75, 95% confidence interval (CI) = 0.69-0.82; P = 4.46 × 10(-10)), with confirmation in independent follow-up samples (659 CeAD cases and 2,648 controls; P = 3.91 × 10(-3); combined P = 1.00 × 10(-11)). The rs9349379[G] allele was previously shown to be associated with lower risk of migraine and increased risk of myocardial infarction. Deciphering the mechanisms underlying this pleiotropy might provide important information on the biological underpinnings of these disabling conditions
Mercury DPM: fast, flexible particle simulations in complex geometries part II: applications
MercuryDPM is a particle-simulation software developed open-source by a global network of researchers. It was designed ab initio to simulate realistic geometries and materials, thus it contains several unique features not found in any other particle simulation software. These features have been discussed in a companion paper published in the DEM7 conference proceedings; here we present several challenging setups implemented in MercuryDPM . Via these setups, we demonstrate the unique capability of the code to simulate and analyse highly complex geotechnical and industrial applications.These tups implemented include complex geometries such as (i) a screw conveyor, (ii) steady-state inflow conditions for chute flows, (iii) a confined conveyor belt to simulate a steady-state breaking wave, and(iii)aquasi-2D cylindrical slice to efficiently study shear flows.MercuryDPM is also parallel, which we showcase via a multi-million particle simulations of a rotating drum. We further demonstrate how to simulate complex particle interactions, including: (i)deformable, charged clay particles; and (ii) liquid bridges and liquid migration in wet particulates, (iii) non-spherical particles implemented via superquadrics. Finally, we show how to analyse and complex systems using the unique micro-macro mapping (coarse-graining) tool MercuryCG
Comparative return of imports into the state of Negri Sembilan during the years, 1916 and 1915.
Supplement to the F.M.S Government Gazette, May 11th, 1917. It also contains 'Comparative return of exports into the state of Negri Sembilan during the years, 1916 and 1915'
DISCRETE TOMOGRAPHY AND FUZZY INTEGER PROGRAMMING
Abstract. We study the problem of reconstructing binary images from four projections data in a fuzzy environment. Given the uncertainly projections, we want to find a binary image that respects as best as possible these projections. We provide an iterative algorithm based on fuzzy integer programming and linear membership functions
Effect of combined natural convection and non-gray gas radiation on entropy generation through a cylindrical annulus
Numerical analysis of entropy generation through non-grey gas radiation in a cylindrical annulus
Amorphous and Semicrystalline Blends of Poly(vinylidene fluoride) and Poly(methyl methacrylate): Characterization and Modeling of the Mechanical Behavior
International audienceAfter extensive studies starting in the 1970s in relation to miscibility and piezoelectric properties, the blends of poly(vinylidene fluoride) (PVDF) and poly(methyl methacrylate) (PMMA) have been revisited with the aim of assessing their mechanical behavior. Depending on the amount of PVDF, either amorphous or semicrystalline blends are produced. Typically, the blends remain amorphous when their PVDF content does not exceed 40 wt. %. Blend composition influence on the values of the glass transition temperature, T(g), and on its mechanical expression, T(alpha), is extensively discussed. Then, emphasis is put on the stress-strain behavior in tension and compression over the low deformation range covering the elastic, anelastic, and viscoplastic response. The reported data depend, as expected, on temperature and strain rate and also, markedly, on blend composition and degree of crystallinity. Molecular arguments, based on the contribution of the glass transition motions are proposed to account for the observed behavior. Thanks to the understanding of phenomena at the molecular level, accurate models can be selected in the view of mechanical modelin
Reconstruction of binary matrices under adjacency and timetabling constraints
We are concerned with binary matrix reconstruction from their orthogonal projections. To the basic problem we add new kinds of constraints such as adjacency constraints among neighbors, and bounded distance. Complexity results and polynomial time algorithms are given
