Search results for "algorithm"

An algorithm for earthquakes clustering based on maximum likelihood

2007

In this paper we propose a clustering technique set up to separate and find out the two main components of seismicity: the background seismicity and the triggered one. We suppose that a seismic catalogue is the realization of a non homogeneous space-time Poisson clustered process, with a different parametrization for the intensity function of the Poisson-type component and of the clustered (triggered) component. The method here proposed assigns each earthquake to the cluster of earthquakes, or to the set of independent events, according to the increment to the likelihood function, computed using the conditional intensity function estimated by maximum likelihood methods and iteratively chang…

Pretreatment T790M mutation detection by ultrasensitive PCR assay as predictor of efficacy in non-small lung cancer (NSCLC) patients treated with 1st…

2019

Restricted Neighborhood Search Clustering Revisited: An Evolutionary Computation Perspective

2013

Protein-protein interaction networks have been broadly studied in the last few years, in order to understand the behavior of proteins inside the cell. Proteins interacting with each other often share common biological functions or they participate in the same biological process. Thus, discovering protein complexes made of groups of proteins strictly related, can be useful to predict protein functions. Clustering techniques have been widely employed to detect significative biological complexes. In this paper, we integrate one of the most popular network clustering techniques, namely the Restricted Neighborhood Search Clustering (RNSC), with evolutionary computation. The two cost functions in…

3D Tools for CH Documentation

2020

The research focuses on the digital Computer Assisted Restoration procedures to guide the measure of integration of an artefact, innovating and implementing traditional research methods. Non-invasive 3D Digitalization techniques with high-performance devices allow the generation of applications for high-resolution visualization of three-dimensional environments with the possibility of navigating, analyzing and consulting virtual models in real time. The innovative application of 3D digital technologies has demonstrated that the integrated use of the new technology can be a useful tool to improve the entire process of collecting, storing and consulting information and data related to diagnos…

Complying With the First Law of Robotics: An Analysis of the Occupational Risks Associated With Work Directed by an Algorithm/Artificial Intelligence

2020

It is increasingly common for companies to use artificial intelligence mechanisms, which may be more or less advanced, to manage work, that is, to establish work shifts and production times, design and allocate tasks for workers, recruit workers, evaluate performance and dismiss employees. Companies rely on technology to gather all the information available, process it and make the management decisions (productivity optimisation) that will benefit them the most. This replaces human supervisors and middle managers, as well as experts in human resources, leaving the management of workers in the hands of automated processes directed by algorithms – or in its most advanced stage, to be undertak…

Enhanced detection of contrast regions in echocardiograms by adaptive quantization

2002

The statistics of ultrasound echo images are governed by Rayleigh statistics. The authors derive some experimentally verifiable predictions of this theory, compare them with experimental results obtained from echocardiographic images, and derive a new color coding scheme, (adaptive quantization) that is adapted to the signal-dependent noise predicted by theory. This results in some technical advantages and in an improved discrimination of regions of the echo image that are enhanced by echo contrast material. >

Sensorless control of permanent magnet synchronous motors for wide speed range applications

2006

This paper deals with sensorless control of Interior Permanent Magnet Synchronous Motors (IPMS) based on the estimation of speed and rotor angular position. The above estimate is based on the injection of high frequency stator currents able to generate a signal similar to that generated by a resolver connected to the axis of the motor. A new digital algorithm has been designed to demodulate the above signal whose implementation can be carried out on the same DSP that processes the control algorithm. In this paper a new scheme of speed and angular position estimator is proposed and justified on the theoretic point of view. The experimental results here shown validate the effectiveness of the…

<title>Human cell texture analysis with quincunx spline wavelet transform</title>

1999

Wavelet transforms are efficient tools for texture analysis and classification. Separable techniques are classically used but present several drawbacks. First, diagonal coefficients contain poor information. Second, the other coefficients contain useful information only if the texture is oriented in the vertical and horizontal directions. So an approach of texture analysis by non-separable transform is proposed. An improved interscale resolution is allowed by the quincunx scheme and this analysis leads to only one detail image where no particular orientation is favored. New orthogonal isotropic filters for the decomposition are constructed by applying McClellan transform on one dimension B-…

Hidden Markov Random Field model and BFGS algorithm for Brain Image Segmentation

2016

Brain MR images segmentation has attracted a particular focus in medical imaging. The automatic image analysis and interpretation became a necessity. Segmentation is one of the key operations to provide a crucial decision support to physicians. Its goal is to simplify the representation of an image into items meaningful and easier to analyze. Hidden Markov Random Fields (HMRF) provide an elegant way to model the segmentation problem. This model leads to the minimization problem of a function. BFGS (Broyden-Fletcher-Goldfarb-Shanno algorithm) is one of the most powerful methods to solve unconstrained optimization problem. This paper presents how we combine HMRF and BFGS to achieve a good seg…

<title>Multiresolution description of range images through 2D quincunx wavelet analysis</title>

1999

In this paper, we present a method for performing a multi- scale analysis on range images by using the wavelet transform, that is capable of revealing multi-resolution information. An accurate non-contact optical system based upon laser triangulation is used to determine the depth information of the object being scanned. The resulting range image is treated as a gray-level image by using a multi- resolution approach based on the generalization of the cascade algorithm using the quincunx wavelet transform. The quincunx wavelet assures very fine analysis. This method allows reconstruction of non-subsampled images that correspond to decompositions previously done at chosen scales. Multi-resolu…