Gaussian density estimates for the solution of singular stochastic Riccati equations

summary:Stochastic Riccati equation is a backward stochastic differential equation with singular generator which arises naturally in the study of stochastic linear-quadratic optimal control problems. In this paper, we obtain Gaussian density estimates for the solutions to this equation

Genome-Wide Linkage in a Highly Consanguineous Pedigree Reveals Two Novel Loci on Chromosome 7 for Non-Syndromic Familial Premature Ovarian Failure

BACKGROUND: The human condition known as Premature Ovarian Failure (POF) is characterized by loss of ovarian function before the age of 40. A majority of POF cases are sporadic, but 10-15% are familial, suggesting a genetic origin of the disease. Although several causal mutations have been identified, the etiology of POF is still unknown for about 90% of the patients.¦METHODOLOGY/PRINCIPAL FINDINGS: We report a genome-wide linkage and homozygosity analysis in one large consanguineous Middle-Eastern POF-affected family presenting an autosomal recessive pattern of inheritance. We identified two regions with a LOD(max) of 3.26 on chromosome 7p21.1-15.3 and 7q21.3-22.2, which are supported as candidate regions by homozygosity mapping. Sequencing of the coding exons and known regulatory sequences of three candidate genes (DLX5, DLX6 and DSS1) included within the largest region did not reveal any causal mutations.¦CONCLUSIONS/SIGNIFICANCE: We detect two novel POF-associated loci on human chromosome 7, opening the way to the identification of new genes involved in the control of ovarian development and function

In-situ structural health monitoring of glass fiber reinforced composites by tufted reinforcement

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From Images or Voxels to FEM models. Application to the meshing of 3D Interlock Composite Structures

International audience3D interlock composites are complex structures composed of thousands of fibers impregnated with resin.The difficulties of creating a mesh of these weaves are known: multiple yarn contacts, interpenetration, nospurious space should be added at the interface, variation of cross-section. A number of approaches proposesto create an idealized geometry as realistic as possible which does not necessarily enable mesh generation.The main difficulty is to transform interpenetrations into conforming contact zones andallow an unstructured tetrahedron mesh generation of the extremely complex shape of the resin. 3D imagessuch as tomography shows this complex arrangements. A 3D model can be easily converted into a voxelrepresentation which is already a FE-model with conforming meshes at the interface between yarns. Thenumber of voxels can be adjusted to the desired accuracy. One of the main shortcoming of thisrepresentation is indeed the jagged effect of the surface model which can seriously alter the accuracy of thefinite element analysis especially overestimated stresses due to the singularities at sharp edges and corners.We propose here an iterative surface smoothing technique inspired from subdivision surface modelling. Nonconnexvolumes are identified and the process is applied on each component while maintaining the interface.A line smoothing technique derived from the surface smoothing is applied at the interface between twoyarns and resin. The smoothing technique can be constrained in order to keep some features such as planarfaces or imposed points. Sharp edges and edges are removed altogether with an undesired terrace-like effectof the voxel model. Nodes are relocated at the end of the process in order to compensate the shrinking of thevolume. The surface of deformed voxels is thereafter split into triangles. Hexahedra (voxels) are quitedeformed during the process and the splitting must be optimized in order to allow a tetrahedron remeshing.A typology of the deformed voxels associated with remeshing configurations into tetrahedra is proposed. Ina few cases, a local remeshing using a 3D mesh generator is performed. The technique proved to be robustand efficient even with highly complex shapes and numerous volumes

Structural health monitoring for GFRP composite by the piezoresistive response in the tufted reinforcements

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Analysis of the impact and compression after impact behavior of tufted laminated composites

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Structural health monitoring by the piezoresistive response of tufted reinforcements in sandwich composite panels

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A New Hydraulic Crash Machine for Composite Structures

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