Search results for "image processing"

Conceptual Characterization of Cybersecurity Ontologies

2020

Part 7:Risk and Security Modeling; International audience; Cybersecurity is known as the practice of protecting systems from digital attacks. Organizations are seeking efficient solutions for the management and protection of their assets. It is a complex issue, especially for great enterprises, because it requires an interdisciplinary approach. The kinds of problems enterprises must deal with and this domain complexity induces misinterpretations and misunderstandings about the concepts and relations in question. This article focus on dealing with Cybersecurity from an ontological perspective. The first contribution is a search of previously existing works that have defined Cybersecurity Ont…

Analysis of the level-crossing rate and average duration of fades of WSSUS channels

2017

Studies of the level-crossing rate (LCR) and the average duration of fades (ADF) are so far only devoted to stochastic processes being a function of one independent variable, which is usually time or in some few cases frequency. In this paper, we study the LCR (ADF) of wide-sense stationary uncorrelated scattering (WSSUS) processes in the time-frequency domain. A closed-form solution will be derived for the so-called time-frequency LCR (ADF) of the absolute value of the time-variant transfer function (TVTF) of WSSUS processes. It is shown that the LCR (ADF) is circularly symmetric in the normalized time-frequency domain. The derived time-frequency LCR contains the time LCR and frequency LCR…

Corrigendum to “Observer-Based Sliding Mode Control for Stabilization of a Dynamic System with Delayed Output Feedback”

2016

Fitting random cash management models to data

2019

Abstract Organizations use cash management models to control balances to both avoid overdrafts and obtain a profit from short-term investments. Most management models are based on control bounds which are derived from the assumption of a particular cash flow probability distribution. In this paper, we relax this strong assumption to fit cash management models to data by means of stochastic and linear programming. We also introduce ensembles of random cash management models which are built by randomly selecting a subsequence of the original cash flow data set. We illustrate our approach by means of a real case study showing that a small random sample of data is enough to fit sufficiently goo…

Long-term ozone exposure of potato: Free radical content and leaf injury analysed by Q-band ESR spectroscopy and image analysis

2008

This paper presents Q-band electron spin resonance (ESR) studies on free radicals (FR) generated in potato leaves exposed to different O(3) levels in open-top chambers (OTC), together with a quantitative study of the relationship between FR signal intensity and area of potato leaf damage. The advantages of Q-band when compared to X-band ESR spectroscopy are analysed, the main advantage being an absence of overlapping between Mn(II) and FR signals, allowing a quantitative study of FR signal intensity. This study also reports on a graphical method developed to quantitatively measure the damaged area on leaves caused by ozone exposure. Results indicate a direct relationship between FR signal i…

Manipulating the alpha level cannot cure significance testing

2018

We argue that making accept/reject decisions on scientific hypotheses, including a recent call for changing the canonical alpha level from p = 0.05 to p = 0.005, is deleterious for the finding of new discoveries and the progress of science. Given that blanket and variable alpha levels both are problematic, it is sensible to dispense with significance testing altogether. There are alternatives that address study design and sample size much more directly than significance testing does; but none of the statistical tools should be taken as the new magic method giving clear-cut mechanical answers. Inference should not be based on single studies at all, but on cumulative evidence from multiple in…

DiDuSoNet: A P2P architecture for Ditributed Dunbar-based Social Networks,

2015

Online Social Networks (OSNs) are becoming more and more popular on the Web. Distributed Online Social Networks (DOSNs) are OSNs which do not exploit a central server for storing users data and enable users to have more control on their profile content, ensuring a higher level of privacy. In a DOSN there are some technical challenges to face. One of the most important challenges is the data availability problem when a user is offline. In this paper we propose DiDuSoNet, a novel P2P Distributed Online Social Network where users can exercise full access control on their data. Our system exploits trust relationships for providing a set of important social services, such as trustness, informati…

Three-Dimensional Flow and Temperature Distribution in Rayleigh-Bènard Convection Using Thermochromic Liquid Crystals and Digital Image Processing

2000

A visual framework to create photorealistic retinal vessels for diagnosis purposes

2020

The methods developed in recent years for synthesising an ocular fundus can be been divided into two main categories. The first category of methods involves the development of an anatomical model of the eye, where artificial images are generated using appropriate parameters for modelling the vascular networks and fundus. The second type of method has been made possible by the development of deep learning techniques and improvements in the performance of hardware (especially graphics cards equipped with a large number of cores). The methodology proposed here to produce high-resolution synthetic fundus images is intended to be an alternative to the increasingly widespread use of generative ad…

Wykorzystanie zasobów baz danych GIS na potrzeby analizy zróżnicowania obszarów wiejskich w aspekcie działań PROW = Application of GIS databases for …

2018

Realizacja działań w ramach Programu Rozwoju Obszarów Wiejskich (PROW) wymaga obiektywnego rozpoznania potrzeb ich wdrażania, w oparciu o wyniki analiz złożonych procesów przyrodniczych i ekono- miczno-demograficznych zachodzących w czasie i przestrzeni obszarów wiejskich. Wzrastająca funkcjonalność Systemów Informacji Geograficznej (GIS) oraz powszechna dostępność do informacji przestrzennej spowodowały, że bazy danych GIS i analizy geoprzestrzenne stały się skutecznym narzędziem wpierającym implementację działań PROW. Celem pracy jest przedstawienie możliwości wykorzystania danych geoinformacyjnych wybranych baz danych GIS do analizy zróżnicowania przestrzennego obszarów wiejskich wojewód…