Search results for "Vision"
showing 10 items of 5066 documents
Les théories de la gouvernance : de la gouvernance des entreprises à la gouvernance des systèmes nationaux
2006
(VF)L'objectif de cet article est de faire une synthèse des théories de la gouvernance. Dans la première partie sont présentées les théories micro de la gouvernance en opposant les théories cognitives aux théories diciplinaires. La seconde partie est dévolue aux théories macro de la gouvernance sur la base de la distinction entre les théories fondées sur l'appropriation de la rente organisationnelle et celles accordant un rôle dominant à la production. Cette synthèse met en évidence que la vision financière de la gouvernance n'est qu'un cas très particulier qui présente de nombreuses limites;(VA)The objective of this article is to make a survey of the different corporate governance theories…
Comment améliorer la prévision des ventes pour le marketing ? Les apports de la théorie du chaos
2013
La littérature en marketing constate un décalage entre les avancées réalisées par les chercheurs qui développent de nouvelles méthodes de prévision des ventes, et l'usage massif de méthodes traditionnelles reposant sur l'hypothèse de linéarité des processus analysés. Cette recherche expose la contribution potentielle de la théorie du chaos à l'amélioration de la prévision des ventes. Une illustration de ces apports est proposée avec une application à la prévision des ventes de consoles de jeux vidéo au Japon. Les résultats mettent en évidence la capacité de la méthode proposée à détecter la présence de chaos dans la série et montrent la possibilité de préciser l'horizon de prévisibilité des…
Model selection using limiting distributions of second-order blind source separation algorithms
2015
Signals, recorded over time, are often observed as mixtures of multiple source signals. To extract relevant information from such measurements one needs to determine the mixing coefficients. In case of weakly stationary time series with uncorrelated source signals, this separation can be achieved by jointly diagonalizing sample autocovariances at different lags, and several algorithms address this task. Often the mixing estimates contain close-to-zero entries and one wants to decide whether the corresponding source signals have a relevant impact on the observations or not. To address this question of model selection we consider the recently published second-order blind identification proced…
Gear classification and fault detection using a diffusion map framework
2015
This article proposes a system health monitoring approach that detects abnormal behavior of machines. Diffusion map is used to reduce the dimensionality of training data, which facilitates the classification of newly arriving measurements. The new measurements are handled with Nyström extension. The method is trained and tested with real gear monitoring data from several windmill parks. A machine health index is proposed, showing that data recordings can be classified as working or failing using dimensionality reduction and warning levels in the low dimensional space. The proposed approach can be used with any system that produces high-dimensional measurement data. peerReviewed
Visual-manual in-car tasks decomposed: text entry and kinetic scrolling as the main sources of visual distraction
2013
Distraction effects of in-car tasks with a touch screen based navigation system user interface were studied in a driving simulator experiment with eye tracking. The focus was to examine which particular in-car task components visually distract drivers the most. The results indicate that all of the visual-manual in-car tasks led to increased levels of experienced demands and to lower driving speeds. The most significant finding was that text entry and kinetic scrolling of lists were the main sources of visual distraction whereas simple selection tasks with familiar target locations led to least severe distraction effects.
Revisiting rainfall to explore exam questions and performance on CS1
2015
The Rainfall problem comprises small tasks that have been used to investigate student performance in introductory programming. We conducted several kinds of analyses to inform our understandings of student performance in CS1 relating to this problem. We analyzed implementation approaches and program errors, as in related studies, and also explored the role of test writing vis-a-vis the most common student error. Finally, using correlation analyses and manual inspection of the exam answers, we studied how well the Rainfall problem served as an exam question. The students' implementation choices reflected their familiarity with particular loop constructs, while the single most common error co…
Interface Detection Using a Quenched-Noise Version of the Edwards-Wilkinson Equation
2015
We report here a multipurpose dynamic-interface-based segmentation tool, suitable for segmenting planar, cylindrical, and spherical surfaces in 3D. The method is fast enough to be used conveniently even for large images. Its implementation is straightforward and can be easily realized in many environments. Its memory consumption is low, and the set of parameters is small and easy to understand. The method is based on the Edwards-Wilkinson equation, which is traditionally used to model the equilibrium fluctuations of a propagating interface under the influence of temporally and spatially varying noise. We report here an adaptation of this equation into multidimensional image segmentation, an…
Role of Acquisition Intervals in Private and Public Cloud Storage Costs
2014
The volume of worldwide digital content has increased nine-fold within the last five years, and this immense growth is predicted to continue in the foreseeable future to reach 8 ZB by 2015. Traditionally, organizations proactively have built and managed their private storage facilities to cope with the growing demand for storage capacity. Recently, many organizations have instead welcomed the alternative of outsourcing their storage needs to the providers of public cloud storage services due to the proliferation of public cloud infrastructure offerings. The comparative cost-efficiency of these two alternatives depends on a number of factors, such as the prices of the public and private stor…
Designing browsing for in-car music player
2012
User interface features of a touch based mobile music player and their comparative impact on driver distraction when searching music albums were investigated. In a driving simulator experiment (N=18) three scrolling methods buttons, swipe and kinetic were compared, whereat the number of music tracks presented in a list-style format varied between three, five and seven items per page. Half of the participants used the music player in a portrait mode and half of them in a landscape mode. It was expected that swipe supports less severe distraction effects than kinetic or button due to systematic page-by-page scrolling and low levels of pointing accuracy required for browsing. Three items shoul…
Depth perception in tablet-based augmented reality at medium- and far-field distances
2013
Current augmented reality (AR) systems often fail to indicate the distance between the user and points of interest in the environment. Empirical evaluations of human depth perception in AR settings compared to real world settings are needed. Our goal in this study was to understand tablet-based AR depth perception by comparing it with real-world depth perception.