Search results for "Lier"

Classification of SD-OCT Volumes for DME Detection: An Anomaly Detection Approach

2016

International audience; Diabetic Macular Edema (DME) is the leading cause of blindness amongst diabetic patients worldwide. It is characterized by accumulation of water molecules in the macula leading to swelling. Early detection of the disease helps prevent further loss of vision. Naturally, automated detection of DME from Optical Coherence Tomography (OCT) volumes plays a key role. To this end, a pipeline for detecting DME diseases in OCT volumes is proposed in this paper. The method is based on anomaly detection using Gaussian Mixture Model (GMM). It starts with pre-processing the B-scans by resizing, flattening, filtering and extracting features from them. Both intensity and Local Binar…

La valutazione della qualità dei servizi ospedalieri: applicazione dei modelli ad equazioni strutturali ad un caso concreto

2002

Primitives detection by a discrete and non linear approach : application to the detection and caracterization of interest points for 3D meshes

2010

This manuscript is dedicated to the detection and caracterization of interest points for 3D meshes. First of all, we show the limitations of the curvature measure on sharp edges, the measure usually used for the analysis of meshes. Then, we present a generalization of the SUSAN operator for meshes, named SUSAN-3D. The saliency measure proposed quantify the local variation of the surface and classify directly the analysed vertices in five classes: salient, crest, flat, valley and cavity. The meshes under consideration are manifolds and can be closed or non-closed, regulars or irregulars, dense or not and noised or not. The accuracy of the SUSAN-3D operator is compared to two curvature operat…

On the distribution of education and democracy

2006

This paper empirically analyzes the influence of the distribution of education on democracy by controlling for unobservable heterogeneity and by taking into account the persistency of some of the variables. The most novel finding is that increase in the education attained by the majority of the population is what matters for the implementation and sustainability of democracy, rather than the average years of schooling. We show this result is robust to issues pertaining omitted variables, outliers, sample selection, or a narrow definition of the variables used to measure democracy.

Gamma-ray position reconstruction in large lanthanum-halide crystals with SiPM readout: analytical vs. neural-network algorithms

2019

The main objective of this research was to achieve an excellent gamma-ray position reconstruction with very large monolithic scintillation crystals coupled to pixelated silicon photosensors. Analyzing the scintillation-light distribution measured along the SiPM-pixels one can get a sub-pixel accuracy for the position reconstruction. The quality of the latter depends on both the characteristics of the crystal-photosensor assembly, and the goodness of the algorithm used to reconstruct the gamma-ray hit location. We have carried out a systematic study for 511 keV gamma-rays using three different crystal thicknesses of 10 mm, 20 mm and 30 mm, all of them with planar geometry and a base size of …

Valutazione dell’efficacia degli interventi progettuali nella costa di ladispoli

2014

Comparison among different dynamic shakedown approaches

2017

The paper concerns the search for the limit load multiplier of structures subjected to seismic actions under shakedown conditions. The search problem is treated referring to two fundamental different approaches: The unrestricted dynamic shakedown approach and a new stochastic one recently proposed. The comparison between the above cited approaches is effected with the aim of evaluate the goodness of the obtainable results and the related computational effort. The structure sensitivity with respect to shakedown is evaluated through the analysis of the shakedown limit load multiplier cumulative distribution function. This function is determined by means of the stochastic approach, adopting th…

Value, supplier dependence and long‐term orientation

2011

PurposeIn organizational markets, many companies tend to reduce the number of providers to focus on establishing relationships with few of them. The purpose of this paper is to analyze the influence of relationship value and dependence of supplier on long‐term orientation and customer loyalty in the setting of relationships between travel agencies and their main providers.Design/methodology/approachA partial least square regression is performed to test a proposed model that links several relational variables with outcomes in terms of customer loyalty.FindingsResults provide support for the positive indirect influence of relationship value on long‐term orientation, while customer dependence …

Robust refinement of initial prototypes for partitioning-based clustering algorithms

2007

Non-uniqueness of solutions and sensitivity to erroneous data are common problems to large-scale data clustering tasks. In order to avoid poor quality of solutions with partitioning-based clustering methods, robust estimates (that are highly insensitive to erroneous data values) are needed and initial cluster prototypes should be determined properly. In this paper, a robust density estimation initialization method that exploits the spatial median estimate to the prototype update is presented. Besides being insensitive to noise and outliers, the new method is also computationally comparable with other traditional methods. The methods are compared by numerical experiments on a set of syntheti…

Il grano duro e la filiera siciliana della pasta

2014

Primi contributi sull'economia della filiera cerealicola siciliana con particolare riferimento alla pasta.