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Monitoring shot-to-shot variations of soft x-ray sources using aluminum foils
No full textInternational audienc
Special Issue on Behavior Adaptation, Interaction, and Artificial Perception for Assistive Robotics
No full textInternational audienceThis special issue aims at examining and promoting recent developments in the Assistive/Social Robotics field and future directions including the related challenges and how these can be overcome with particular focus on computational intelligence methodologies. With robots being integrated more and more in our environments and daily activities, the effectiveness of robotics applications has to rely on robots' ability to perceive, reason, and adapt on-the-fly to the users' behavior and needs. In particular, the development of personal robots, as assistive technological tools, challenges researchers to develop socially intelligent and adaptive robots that can collaborate with people in real environment. This special issue is comprised of 14 papers, fostering discussions and investigations in robot behavior adaptation and learning, in socially assistive robotics, and in developing reliable systems for natural interactions between humans and robots. Several aspects and perspectives are taken into consideration by the authors covering various topics such as adaptability during real-world human-robot interactions ; new reinforcement learning and learning by teaching techniques especially used in the context of child-robot interaction ; social robot responses, perception and adaptation by means of a semantic representation; robots acceptability and security. Furthermore, several assistive applications for the elderly, children, and people are presented. B Mariacarla Staff
Analyse spectrale et simulation numérique de cavités contenant un matériau négatif
No full textThis thesis achieves a theoretical and numerical studies of cavities partially filled with a negative material, that is a material for which the magnetic permeability and/or the electric permittivity (or at least their real part) become negative in some frequency ranges. This study is part of the main thrust of the work started in our team focusing on the electromagnetic wave propagation in presence of such negative materials, at a given fraquency. The purpose of this thesis is to take into account the frequency dispersion, that is the frequency dependence of the permeability and/or the permittivity, considering the frequency as the spectral parameter. We highlight the essential spectrum arising from the presence of negative material, as well as the resulting resonance phenomena, for different models describing this material. The theoretical study focuses on the case of polygonal bi-dimensional cavities for the Drude and the Lorentz models (with dissipation or not). The theoretical study of the simplest model (the non dissipative Drude model) is extended to the case of a curved (but regular) interface. This model is also the subject of a numerical study, aimed at exploring the effect of a finite element discretization of the theoretical problem, and thus highlight the difficulties to numerically notice some of the resonance phenomena.Cette thèse réalise une étude théorique et numérique du spectre de cavités partiellement composées de matériau négatif, c'est-à-dire de matériau pour lequel la perméabilité magnétique et/ou la permittivité électrique (ou au moins leur partie réelle) deviennent négatives dans certaines plages de fréquences. Cette étude s'inscrit dans la continuité des travaux engagés dans notre laboratoire qui se concentrent sur la propagation des ondes électromagnétiques en présence de matériau négatif, à fréquence fixée. L'objectif de cette thèse est de prendre en compte la dispersion fréquentielle, autrement dit la dépendance en fréquence de la perméabilité et de la permittivité, en considérant la fréquence comme paramètre spectral. Nous mettons en évidence le spectre essentiel résultant de la présence de matériau négatif ainsi que les phénomènes de résonance qui en découlent, pour différents modèles décrivant ce matériau.L'étude théorique se concentre sur le cas de cavités bidimensionnelles polygonales pour les modèles de Drude et de Lorentz (avec et sans dissipation). L'étude théorique du modèle le plus simple (Drude non dissipatif) est étendue au cas d'une interface courbe (mais régulière).Ce modèle fait également l'objet d'une étude numérique, visant à explorer l'effet d'une discrétisation éléments finis du problème théorique, et ainsi mettre en avant les difficultés à observer numériquement certains des phénomènes de résonance
Integration of Sentinel-1A and Sentinel-2B Data for Land Use and Land Cover Mapping of the Kirkuk Governorate, Iraq
No full textInternational audienceLand use and land cover maps are essential to aid our knowledge of modelling the environment, managing water. Multispectral and SAR Satellite data consider the main and valuable resource for LULC mapping. Because of the presence of clouds, creating a precise LULC map using multispectral data is a challenge. Herein, the goal of this study is to generate a precise map of LULC of Kirkuk city using different classification methods and to evaluate the impact of combining SAR and optical Sentinel (1A and 2B) data on classification efficiencies. Gram–Schmidt (GS) method was applied to combine the multispectral Sentinel 2B data and Sentinel-1A (VH, VV). The efficiency of using four commonly-used classification algorithms was then compared to specify the optimal method for LULC classification. The finding reveals that the greatest accuracy of 97.93% with a kappa coefficient of 0.97 was produced using the SVM algorithm applied to multispectral Sentinel-2B data. while the DT-KNN algorithm was most efficient when it applied to Sentinel-2B-VH data with an accuracy of 97.60 %. The overall accuracy of RF is also improved when it applied to Sentinel-1A-VV than Sentinel-1A-VH and multispectral data. Additionally, the method developed will be helpful to researchers who continue to use diverse data sources to map various regions. These mapping results represent an essential step toward future soil mapping and mineral estimation
A Hadoop-Based Platform for Patient Classification and Disease Diagnosis in Healthcare Applications
No full textInternational audienceNowadays, the increasing number of patients accompanied with the emergence of new symptoms and diseases makes heath monitoring and assessment a complicated task for medical staff and hospitals. Indeed, the processing of big and heterogeneous data collected by biomedical sensors along with the need of patients' classification and disease diagnosis become major challenges for several health-based sensing applications. Thus, the combination between remote sensing devices and the big data technologies have been proven as an efficient and low cost solution for healthcare applications. In this paper, we propose a robust big data analytics platform for real time patient monitoring and decision making to help both hospital and medical staff. The proposed platform relies on big data technologies and data analysis techniques and consists of four layers: real time patient monitoring, real time decision and data storage, patient classification and disease diagnosis, and data retrieval and visualization. To evaluate the performance of our platform, we implemented our platform based on the Hadoop ecosystem and we applied the proposed algorithms over real health data. The obtained results show the effectiveness of our platform in terms of efficiently performing patient classification and disease diagnosis in healthcare applications
Multiscale pink-beam microCT imaging at the ESRF-ID17 biomedical beamline
No full textInternational audienc
Modular Deployment of UML Models for V&V Activities and Embedded Execution
No full textInternational audienc
Quantum erasing of laser emission in N + 2
No full textInternational audienceCavity-free lasing of N + 2 induced by a femtosecond laser pulse at 800 nm is nearly totally suppressed by a delayed twin control pulse. We explain this surprising effect within the V-scheme of lasing without population inversion. A fast transfer of population between nitrogen ionic states X 2 Σ + g and A 2 Π u , induced by the second pulse, terminates the conditions for amplification in the system. Appearance of short lasing bursts at delays corresponding to revivals of rotational wave packets are explained along the same lines
The turnpike property in maximization of microbial metabolite production
No full textInternational audienceWe consider the problem of maximization of metabolite production in bacterial cells. Numerical methods showed that the major phase of the solutions for different initial states and final times is the singular regime which exhibits a special structure reminiscent of the turnpike phenomenon. We prove that singular trajectories indeed have the turnpike property by providing an estimate both on singular trajectories and on the associated controls. This result can be further used for construction of simple realistic suboptimal control strategies
Effective resonant model and simulations in the time-domain of wave scattering from a periodic row of highly-contrasted inclusions
No full textInternational audienceThe time-domain propagation of scalar waves across a periodic row of inclusions is considered in 2D. As the typical wavelength within the background medium is assumed to be much larger than the spacing between inclusions and the row width, the physical configuration considered is in the low-frequency homogenization regime. Furthermore, a high contrast between one of the constitutive moduli of the inclusions and of the background medium is also assumed. So the wavelength within the inclusions is of the order of their typical size, which can further induce local resonances within the microstructure. In Pham et al. (2017), two-scale homogenization techniques and matched-asymptotic expansions have been employed to derive, in the harmonic regime, effective jump conditions on an equivalent interface. This homogenized model is frequency-dependent due to the resonant behavior of the inclusions. In this context, the present article aims at investigating, directly in the time-domain, the scattering of waves by such a periodic row of resonant scatterers. Its effective behavior is first derived in the time-domain and some energy properties of the resulting homogenized model are analyzed. Time-domain numerical simulations are then performed to illustrate the main features of the effective interface model obtained and to assess its relevance in comparison with full-field simulations