Search results for "Format"

A comparison between two feature selection algorithms

2017

This article provides a comparison of two feature selection algorithms, Information Gain Thresholding and Koller and Sahami's algorithm in the context of text document classification on the Reuters Corpus Volume 1 dataset. The algorithms were evaluated by testing the performance of classifiers trained on the features they select from a given dataset. Results show that Koller and Sahami's algorithm consistently outperforms Information Gain Thresholding by capturing interactions between features and avoiding redundancy among features, although it achieves its gains through increased complexity and longer running time.

Computing variations of entropy and redundancy under nonlinear mappings not preserving the signal dimension: quantifying the efficiency of V1 cortex

2021

In computational neuroscience, the Efficient Coding Hypothesis argues that the neural organization comes from the optimization of information-theoretic goals [Barlow Proc.Nat.Phys.Lab.59]. A way to confirm this requires the analysis of the statistical performance of biological systems that have not been statistically optimized [Renart et al. Science10, Malo&Laparra Neur.Comp.10, Foster JOSA18, Gomez-Villa&Malo J.Neurophysiol.19]. However, when analyzing the information-theoretic performance, cortical magnification in the retina-cortex pathway poses a theoretical problem. Cortical magnification stands for the increase the signal dimensionality [Cowey&Rolls Exp. Brain Res.74]. Conventional mo…

Paschen β line shape studies in low-temperature plasmas

2003

Line shape calculations and measurements of the Paschen β line of hydrogen (λ=12818 Å) are reported. Measurements were performed at electron densities of the plasma between 1015 cm-3 and 1016 cm-3. A wall-stabilized arc operated at atmospheric pressure in a helium-hydrogen gas mixture was applied as the excitation source. The radiation of the plasma, originating from nearly homogeneous plasma layers, in the end-on direction, was analyzed. A grating spectrometer equipped with a CCD detector was used for the radiation detection. The measured line profiles are compared with results of available experimental and theoretical Stark broadening data e.g. based on simulation techniques, applied also…

Crowdsourcing as a mode of open innovation: Exploring drivers of success of a multisided platform through system dynamics modelling

2020

This article aims to explore drivers of success of a crowdsourcing platform. The study conceptualizes crowdsourcing as a mode of open innovation and places such a concept within the context of the sharing economy. Upon this framework, the paper analyses the case of InnoCentive, a successful crowdsourcing platform where innovation-driven organizations search for solutions to their R&D tasks. The system dynamics model frames main InnoCentive business processes and offers a causal perspective on the relationships between platform performance—in terms of users base—and resources structure. The discussion on simulation outputs is carried out through a dynamic performance management view of p…

Timing the information system upgrade

2010

A system upgrade requires careful planning as its implications to organizational systems might be enormous. Although in IS literature the requirements and process of systems upgrade have been discussed, the timing when to upgrade and what factors guide it has been of lesser interest. Consequently, in this paper we focus on information systems upgrading and its timing from the perspective of the user organization. Upgrading is enabled by the availability of a new software version. When to upgrade, meanwhile, is determined by the business interests of the customer organization, business calendar, development projects, and the vendor. These factors were identified by interviewing 14 IT manager…

Systematic conformational search analysis of the SRR and RRR epimers of 7-hydroxymatairesinol

2010

An extensive and systematic conformational search was performed on the two epimers of the natural lignan 7-hydroxymatairesinol (HMR), by means of a home-made Systematic Conformational Search Analysis (SCSA) code, designed to select more and more stable conformers through sequential geometry optimization of trial structures at increasing levels of calculation theory. In the present case, the starting molecular structures were selected by the semi-empirical AM1 method and filtered – i.e. decreased in number by choosing the more stable species – on the basis of their energy calculated by the HF method and the 6-31G(d) basis set. The geometries obtained were further refined by performing densit…

Controverse : l'efficacité de la vidéosurveillance

2012

revue "M3. Société urbaine et action publique"quadrimestriel édité par la Direction de la Prospective du Grand Lyon; En juillet 2007, le ministère de l’Intérieur a lancé un vaste plan de développement de la vidéosurveillance dans les espacesurbains. Cinq ans plus tard, l’efficacité de ces dispositifs n’est toujours pas démontrée, qu’il s’agisse de préventionde la délinquance ou d’aide à l’élucidation d’affaires criminelles. La vidéosurveillance dite intelligente constitue-t-elle une solution pour pallier ce déficit de résultat ?

Traitements et cancer : systèmes d’informations et représentations d’un jeune public – étude comparative Stafford-Dijon

2015

Transitions en système

2020

Cette illustration conçue par l'auteur et co-réalisée avec l'association Alterre Bourgogne-Franche-Comté vise à synthétiser le concept de la Transition, fonctionnant comme un système, où chaque élément est lié aux autres, de telle sorte qu'on ne peut efficacement concevoir une banche de transition sans structurer les autres dans une même dynamique.Cette modélisation est issue de travaux de recherche de l'auteur qui sont en cours de publication (sur 2022 et 2023) dans le cadre de l'Observatoire de la Transition Socio-Écologique (MSHE C. N. Ledoux, Université de Franche-Comté et CNRS, Université de Bourgogne), et dans le cadre d'une Habilitation à Diriger les Recherches en cours.

Information Integration, Coordination Failures, and Quality of Prescribing

2020

Poor information flows hamper coordination, potentially leading to suboptimal decisions in health care. We examine the effects of a nationwide policy of information integration on the quality of prescribing. We use the rollout of an electronic prescribing system in Finland and prescription-level administrative data. We find no effect on the probability of co-prescribing harmful drug combinations in urban regions. In rural regions, this probability reduces substantially, by 35 percent. The effect is driven by prescriptions from unspecialized physicians and from multiple physicians. Improving the local information environment thus enhances coordination and narrows differences in the quality o…