4,657 research outputs found
WHIDE—a web tool for visual data mining colocation patterns in multivariate bioimages
Motivation: Bioimaging techniques rapidly develop toward higher resolution and dimension. The increase in dimension is achieved by different techniques such as multitag fluorescence imaging, Matrix Assisted Laser Desorption / Ionization (MALDI) imaging or Raman imaging, which record for each pixel an N-dimensional intensity array, representing local abundances of molecules, residues or interaction patterns. The analysis of such multivariate bioimages (MBIs) calls for new approaches to support users in the analysis of both feature domains: space (i.e. sample morphology) and molecular colocation or interaction. In this article, we present our approach WHIDE (Web-based Hyperbolic Image Data Explorer) that combines principles from computational learning, dimension reduction and visualization in a free web application
Multiresolution signal decomposition schemes. Part 2: Morphological wavelets
In its original form, the wavelet transform is a linear tool. However, it has been increasingly recognized that nonlinear extensions are possible. A major impulse to the development of nonlinear wavelet transforms has been given by the introduction of the lifting scheme by Sweldens. The aim of this report, which is a sequel to a previous report devoted exclusively to the pyramid transform, is to present an axiomatic framework encompassing most existing linear and nonlinear wavelet decompositions. Furthermore, it introduces some, thus far unknown, wavelets based on mathematical morphology, such as the morphological Haar wavelet, both in one and two dimensions. A general and flexible approach for the construction of nonlinear (morphological) wavelets is provided by the lifting scheme. This paper discusses one example in considerable detail, the max-lifting scheme, which has the intriguing property that it preserves local maxima in a signal over a range of scales, depending on how local or global these maxima are
A Hybrid Deep Learning Approach for Texture Analysis
Texture classification is a problem that has various applications such as
remote sensing and forest species recognition. Solutions tend to be custom fit
to the dataset used but fails to generalize. The Convolutional Neural Network
(CNN) in combination with Support Vector Machine (SVM) form a robust selection
between powerful invariant feature extractor and accurate classifier. The
fusion of experts provides stability in classification rates among different
datasets
Application of digital interferogram evaluation techniques to the measurement of 3-D flow fields
A system for digitally evaluating interferograms, based on an image processing system connected to a host computer, was implemented. The system supports one- and two-dimensional interferogram evaluations. Interferograms are digitized, enhanced, and then segmented. The fringe coordinates are extracted, and the fringes are represented as polygonal data structures. Fringe numbering and fringe interpolation modules are implemented. The system supports editing and interactive features, as well as graphic visualization. An application of the system to the evaluation of double exposure interferograms from the transonic flow field around a helicopter blade and the reconstruction of the three dimensional flow field is given
From homogeneous to fractal normal and tumorous microvascular networks in the brain
We studied normal and tumorous three-dimensional (3D) microvascular networks in primate and rat
brain. Tissues were prepared following a new preparation technique intended for high-resolution
synchrotron tomography of microvascular networks. The resulting 3D images with a spatial
resolution of less than the minimum capillary diameter permit a complete description of the entire
vascular network for volumes as large as tens of cubic millimeters. The structural properties of the
vascular networks were investigated by several multiscale methods such as fractal and power-
spectrum analysis. These investigations gave a new coherent picture of normal and pathological
complex vascular structures. They showed that normal cortical vascular networks have scale-
invariant fractal properties on a small scale from 1.4 lm up to 40 to 65 lm. Above this threshold,
vascular networks can be considered as homogeneous. Tumor vascular networks show similar
characteristics, but the validity range of the fractal regime extend to much larger spatial dimensions.
These 3D results shed new light on previous two dimensional analyses giving for the first time a
direct measurement of vascular modules associated with vessel-tissue surface exchange
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