To improve the results of the Delay-And-Sum (DAS) beamformer a weighting factor based on a measurement of the phase dispersion of the signals in the image point under consideration has been proposed. With this objective, the spectral analysis of the phase dispersion is used here to obtain a new descriptor that can be easily computed and introduced as a ponderation factor in the beamforming proc...

This paper describes the problem of modelling toxicity of environmental pollutants using molecular descriptors from a systems theoretical viewpoint. It is shown that current toxicity modelling problems systematically incorporate very high levels of noise a priori. By means of a set of individual and combined models self-organised by KnowledgeMiner from a high-dimensional molecular descriptor da...

The recently introduced molecular descriptor (Single Exponential Decay Detector - SEDD) [P. de Silva, J. Korchowiec, T. A. Wesolowski, ChemPhysChem 2012, 13, 3462] is used to visualize bonding patterns in molecules. In each point of space SEDD is simply related to the electron density: SEDD(r) = In[1/rho2(del(del rho/rho)2)2]. Either experimental or computed densities rho(r) can be used to eval...

This paper is concerned with the problem of robust stability of Markovian jump singularly perturbed descriptor systems with uncertain switchings and nonlinear perturbations for any 2 .0, N , where N is a pre-defined positive scalar. A linear matrix inequality (LMI) condition is firstly established to guarantee the existence and uniqueness of a solution. Then, an -independent condition in terms ...

In this document, the SURF detector-descriptor scheme used in the OpenSURF library is discussed in detail. First the algorithm is analysed from a theoretical standpoint to provide a detailed overview of how and why it works. Next the design and development choices for the implementation of the library are discussed and justified. During the implementation of the library, it was found that some ...

In this article, we describe the recognition system of Amazigh handwritten letters. The SURF descriptor, specifically the SURF-36, and the GIST descriptor are used for extracting feature vectors of each letter from our database which consists of 25740 manuscripts isolated Amazigh characters. All the feature vectors of each letter form a training set which is used to train the neural network so ...

In this work, we present a novel local descriptor for video sequences. The proposed descriptor is based on histograms of oriented 3D spatio-temporal gradients. Our contribution is four-fold. (i) To compute 3D gradients for arbitrary scales, we develop a memory-efficient algorithm based on integral videos. (ii) We propose a generic 3D orientation quantization which is based on regular polyhedron...

Various types of moments have been used to recognize image patterns in a number of applications. However, only few works have paid attention to the completeness property of the invariant descriptor set, which is of fundamental importance from the theoretical as well as the practical points of views. This paper proposes a systematic method to extract a complete set of similarity invariants (tran...

Humans are extremely proficient at perceiving natural scenes and understanding their contents. Scene recognition in Human is the natural activity by which human can easily recognize the scene even if the scene is complex, partially occluded or blurred. In machine vision the recognition rate is less compared with human vision. To improve the recognition rate of the machine vision an efficient st...