23 research outputs found

    Toward a multiscale modeling framework for understanding serotonergic function

    Get PDF
    Despite its importance in regulating emotion and mental wellbeing, the complex structure and function of the serotonergic system present formidable challenges toward understanding its mechanisms. In this paper, we review studies investigating the interactions between serotonergic and related brain systems and their behavior at multiple scales, with a focus on biologically-based computational modeling. We first discuss serotonergic intracellular signaling and neuronal excitability, followed by neuronal circuit and systems levels. At each level of organization, we will discuss the experimental work accompanied by related computational modeling work. We then suggest that a multiscale modeling approach that integrates the various levels of neurobiological organization could potentially transform the way we understand the complex functions associated with serotonin

    Exploring Local Governance and E-Services in Qatar

    No full text
    Properly implemented, e-government enables improved government efficiency and greater engagement with citizens. The State of Qatar has implemented many e-government initiatives but little has been done to investigate their progress. This study aims to bridge the knowledge gap by shedding the light on a specific e-government initiative: the Baladiya application system, the electronic service for municipalities. It uses qualitative data from semi-structured interviews conducted with the director of customer service in each of the municipalities in Qatar. An inductive approach allowed findings to emerge. E-government provides a broad array of services to local users however three main aspects remain problematic. First, the high quantity but low quality of information received from users via e-government hinders the customer relations. Second, while services are readily available, e-government channels are not widely adopted. Finally, the complex process for service delivery contributes to create a relatively opaque user experience

    Influence of compaction pressure on the mechanical and acoustic properties of compacted earth blocks: An inverse multi-parameter acoustic problem

    No full text
    International audienceIn this work we focus on the study of the acoustic and mechanical behavior of compressed earth blocks (CEBs). The aim was to study the influence of compaction pressure on the compressive strength and intrinsic acoustic parameters influencing sound absorption of these materials (porosity, tortuosity, airflow resistivity, viscous characteristic length). Specimens made by varying the applied compaction pressure and therefore having various bulk densities were studied. Low bulk density CEBs where stabilized by adding 15% cement. The acoustic absorption coefficients of the different specimens were determined experimentally employing data obtained using the Kundt tube. The intrinsic acoustic parameters were identified by minimizing the discrepancies between the experimentally measured absorption coefficient (α) and the theoretical one modeling the CEBs using the equivalent fluid model. The results showed that the acoustic and mechanical behavior of CEBs were strongly influenced by the applied compaction pressure including, inter alia, the bulk density of the specimen and the added cement used as stabilizer

    Characterization of compressed earth blocks using low frequency guided acoustic waves

    No full text
    International audienceThe objective of this work was to analyze the influence of compaction pressure on the intrinsic acoustic parameters (porosity, tortuosity, airflow resistivity, viscous and thermal characteristic lengths) of compressed earth blocks through their identification by solving an inverse acoustic wave transmission problem. A low frequency acoustic pipe (60-6000 Hz of length 22 m, internal diameter 3.4 cm) was used for the experimental characterization of the samples. The parameters were identified by the minimization of the difference between the transmission coefficients data obtained in the pipe with that from an analytical interaction model in which the compressed earth blocks were considered as having rigid frames. The viscous and thermal effects in the pores were accounted for by employing the Johnson-Champoux-Allard-Lafarge model. The results obtained by inversion for high-density compressed earth blocks showed some discordance between the model and experiment especially for the high frequency limit of the acoustic characteristics studied. This was as a consequence of applying high compaction pressure rendering them very highly resistive therefore degrading the signal to noise ratios of the transmitted waves. The results showed that the airflow resistivity was very sensitive to the degree of the applied compaction pressure used to form the blocks

    Modernizing Training on Renewable Energies in the Maghreb Transfer of experience (MOMATE)

    No full text
    Le projet vise à développer une formation de type DUT (Diplôme Universitaire de Technologie) en ingénierie des Energies Renouvelables et à soutenir l'émergence de technopoles spécialisées dans les Energies Renouvelables. L'objectif est de développer des compétences permettant d'acquérir des connaissances de base sur la production d'électricité à partir d'énergies renouvelables (éolienne, solaire, photovoltaïque, etc.). El proyecto pretende desarrollar un programa de formación como el DUT (Diplôme Universitaire de Technologie) en ingeniería de Energías Renovables y apoyar la aparición de tecnopolos especializados en Energías Renovables. Para ello se pretende desarrollar competencias que permitan adquirir conocimientos básicos sobre la producción de energía eléctrica a partir de energías renovables (eólica, solar, fotovoltaica, etc.)The project aims to develop a DUT (University Diploma of Technology) type training in Renewable Energies engineering and to support the emergence of technology parks specializing in Renewable Energies. The objective is to develop skills allowing to acquire basic knowledge on the production of electricity from renewable energies (wind, solar, photovoltaic, etc.). The project intends to launch a training program such as the DUT (University Diploma of Technology) in Renewable Energy Engineering and to support the appearance of engineers specializing in Renewable Energy. Para ello claims to desarrollar competences that allow to acquire basic knowledge sober the production of electrical energy from renewable energies (electrical, solar, photovoltaic, etc.)MOMAT
    corecore