Search results for "PROB"
showing 10 items of 8859 documents
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…
Combining similarity measures in content-based image retrieval
2008
The purpose of content based image retrieval (CBIR) systems is to allow users to retrieve pictures from large image repositories. In a CBIR system, an image is usually represented as a set of low level descriptors from which a series of underlying similarity or distance functions are used to conveniently drive the different types of queries. Recent work deals with combination of distances or scores from different and usually independent representations in an attempt to induce high level semantics from the low level descriptors of the images. Choosing the best method to combine these results requires a careful analysis and, in most cases, the use of ad-hoc strategies. Combination based on or…
Employing fuzzy logic in the diagnosis of a clinical case
2010
Fuzzy logic is a logical calculus which operates with many truth values (while classical logic works with the two values of true and false). Since fuzzy logic considers the truth of scientific statements like something softened, it is fruitfully applied to the study of biological phenomena, biology is indeed considered the field of complexity, uncertainty and vagueness. In this paper fuzzy logic is successfully applied to the clinical diagnosis of a patient who suffers from different diseases bound by a complex causal chain. In this work it is presented a mathematical foundation of fuzzy logic (with connectives and inference rules) and then the application of fuzzy reasoning to the study of…
Cyber Security Strategy Implementation Architecture in a Value System
2018
In this chapter, we introduce an approach toward enhancing the quality of strategy implementation. As a framework, we use cybersecurity strategy implementation planning and execution. Justification for this work is the observed need to be able to perform strategy readjustment processes quickly and in an agile way, when needed. This requires processes and practices that are simple enough and executable with small resources in a relatively short timeframe. The problem statement can be formulated as follows: “We need to determine an utterly simplified, noncomplicated model to help us to tackle the complex problem of implementing a cybersecurity strategy of adequate efficiency in a changing ope…
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. >
An unsupervised region growing method for 3D image segmentation
1995
The paper deals with 3D shape decomposition problem, objects are modelled as finite unions of almost-convex primitives. A new region growing method is proposed to extract meaningful objects parts. Parts are individuated by performing a set-partitioning of surface dominating points. The partition step returns labelled seeds from which to start a region growing procedure that propagate labels onto object surface patches. A fuzzy concept of λ-convexity is introduced to test noised real images. Experimental results are given.
Spatial homogeneity from temporal stability: Exploiting the combined hyper-frequent revisit of Terra and Aqua to guide Earth System Science
2021
Abstract The terrestrial component of the Earth system has witnessed considerable changes in the past decades due to anthropogenic action. Throughout this period, the NASA Terra mission has been constantly monitoring the surface with the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument. When combined with the MODIS instrument on-board of the Aqua platform, we obtain a hyper-frequent revisit capability providing sub-daily observations globally at a moderate resolution of ~250 m, but with a strong multi-angular variation of the observation footprint. Here we propose to exploit this particular configuration provided by the combined Terra + Aqua constellation to infer spatial ho…
Extending the Transactional View on Public–Private Partnership Projects: Role of Relational and Motivational Aspects in Goal Alignment
2019
AbstractIn public–private partnerships (PPPs), aligning the goals of the public sector with those of the private contractor is usually achieved using incentives informed by agency theory. However, ...
Signaling through the 2008 Beijing Olympics—Using Mega Sport Events to Change the Perception and Image of the Host
2011
Abstract This paper provides an analysis on internet news reports about the Beijing Olympics 2008 and how China signaled throughout the event to external target groups. The analysis shows how the geographical areas China, USA, Europe and the “Rest of the World” perceived the Games. The results were interpreted regarding the principal agent theories' signaling to reduce information asymmetry for business and tourism and costly signaling to generate symbolic capital. Seven hundred and forty news reports were collected between 1 July and 30 September 2008, using Google Alerts with the keywords “Olympic Games Beijing 2008”. The reports were analysed with a quantitative content analysis using a …
Optimization of the straightness measurements on rough surfaces by Monte Carlo simulation
2013
Summary The straightness error of a coordinate measuring machine (CMM) is determined by measuring a rule standard. Thanks to a reversal technique, the straightness uncertainty of the CMM is theoretically dissociated from the straightness uncertainty of the rule. However, stochastic variations of the whole measurement system involve uncertainties of the CMM straightness error. To quantify these uncertainties, different sources of stochastic variations are listed with their associated probability density functions. Then Monte Carlo methods are performed first to quantify error and secondly to optimize measurement protocol. It is shown that a 5-measurement distance from 0.1 mm to each measurem…