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L' ail en thérapeutique (de l'Egypte ancienne à nos jours)
No full textAIX-MARSEILLE2-BU Pharmacie (130552105) / SudocSudocFranceF
Particle swarm optimization applications to mpeg-4 transmission over ZigBee
No full textThe IEEE 802.15.4 standard commonly known as Zig8ee is a wireless sensor targeted at applications that require low data rate, low power and less expense. IEEE 802.15.4 standard is limited to a through-rate of 250kbps maximum providing supports for small packet file transitions and is design to provide highly efficient connectivity. Hence, IEEE 802.15.4 is not designed and cannot be used to transfer large amounts of data. Therefore, in this research MPEG-4 video transmission over ZigBee is the aim as its bandwidth is too low and the limitation could become a real problem which makes the video transmission over IEEE 802.15.4 networks difficult to achieve. Due to the low bandwidth of the ZigBee any large amount of data needs to be optimized at the targeted bitrate. Optimization techniques are widely used in engineering and computer science as well as being used in real environment applications to overcome complex issues and in particular; an artificial intelligence technique known as Particle Swann Optimization (PSO) has becoming very popular. PSO is a population-based stochastic optimization technique, inspired by the social behavior of flocks of birds, and colonies of ants and bees. Such intelligence is decentralized, self-organized and distributed throughout an environment and used by swarm to solve problems. In this research, the problem solving strategy decided on the use of PSO to optimize the transmission of MPEG-4 video over Zig8ee, which requires a much lower computation and accordingly it can be executed faster. A novel solution to transmit MPEG-4 over IEEE 802.15.4 has been developed and this research further utilizes a technique to regulate the quantization patterns and output an optimal frame rate by using an "Adaptive Scalar Quantization", which prevents excessive data loss of MPEG-4 video over IEEE 802.15.4 transmission. The computer simulation results confirm that adaptive scalar quantization video coding do improve the quality of picture and reduce data loss and prevents excessive data loss, and use of particle swarm optimization can improve QoS and empower video within the MPEG-4 compression technique to be transmitted over IEEE 802.15.4 standard compared to conventional MPEG video transmissions.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Does the police service need a values-based decision- making model : if so, what should that model look like?
No full textUK policing lacked a single decision making mode! which explicitly required decision makers to consider values affecting their judgement. Motivation for the applied aspect of this work was to develop such a model. The wider research concerned the identification of the values underpinning policing. Consequently, it was essential to understand how values were engaged with and reflected by policing. Policing here was defined as a profession and a preliminary hypothesis for the research was that a single set of values would cross cut the service. An analysis of the stated police values across services in the UK indicated this was not the case. A review of the literature confirmed that in reality, officers take decisions that require discretion. Whilst this was necessary to ensure legitimacy, little training was offered in the application and understanding of discretion. From the literature it was apparent policing reflected various ethical theories at different times. However the service slanted towards the deontological. This position which argues this was reflected within interviews undertaken for the research. From the data, conclusions were drawn that policing was predicated on the three values of integrity, fairness and respect; values which were also reflected in submissions made by members of internet based professional networks. Interviews and focus groups also established that 'service values', i.e. those which underpinned the generic delivery of policing, were insufficient to guide officers in decision making on the ground. This research demonstrated that policing would benefit from a values-based decision-making model. The model was developed, piloted and evaluated in parallel with research for this thesis. As a result of the study, knowledge has been added to policing through the development of this model. It now forms a component of the recently endorsed National Decision Making Model for policing (ACPO Professional Ethics:National Decision Model 2012) and has become part of the curriculum for accredited firearms and senior leadership training in Scotland. Additionally, integrity and fairness have been included in the Scottish Government's proposed new Oath of Constable. As a result of this research, the author is involved with Government in developing definitions for these terms.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
The background to the Representation of the People Act of 1918
No full textEThOS - Electronic Theses Online ServiceGBUnited Kingdo
Static and fatigue behaviour of simply supported and continuous composite beams of steel and concrete
No full textEThOS - Electronic Theses Online ServiceGBUnited Kingdo
Activities of the Slovak Centre of Scientific and Technical Information in the field of Grey Literature
No full textIn this year Slovak Centre of Scientific and Technical Information (CVTI SR) celebrates the 75th anniversary of its establishment. In course of its existence our institution went through various organizational changes and we can say that today it is not only a library but also an information centre supporting science in Slovakia, participating in many national and international projects.
The main objective of paper is to inform the international grey literature community about the mission, objectives and activities of CVTI SR as an institution, which is the only one in Slovakia comprehensively dealing with grey literature.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
GreyGuide - Guide to Good Practice in Grey Literature: A Community Driven Open Resource Project
No full textThe goal of this project is to develop an open source repository of good practices in the field of grey literature. That which originated in monographic form will now open and expand to include content from the global grey literature community. Such practices will range from the production and processing of grey literature through to its distribution, uses, and preservation. The repository will contain guidelines such as those in handling theses and dissertations, how to write research reports, metadata required for working papers as well as good practices in the subject areas of agriculture, health, education, energy, environment, et cetera. The purpose of an online repository of good practice in grey literature will provide the many stakeholders in government, academics, business and industry with the benefits of experience, sustained management, and proven results.
The procedure initially applied in this project deals with the design and development of a template that will capture data and information about published as well as proposed good practices within a standard format. While the metadata captured in the template are indeed standardized, their accompanying full-text documents need not be. Furthermore, the template seeks to identify intended users of a good practice, as well as metadata that will facilitate the search and retrieval of records in the repository. Technical developments related to the design and construction of the repository, its eventual platform as well as its maintenance are other related issues addressed in the project. While there are no direct costs associated with the project, each partner is committed to allocate human and material resources needed to carry out their related tasks.
It is expected that the initial phase in acquiring records for the repository will rely on channels available through the Grey Literature Network Service. Populating the repository will be somewhat time-consuming and the first harvest will not produce an abundance of records. The project is long term; however it is all the more worthwhile. The GreyGuide will provide a unique resource in the field of grey literature that is long awaited and which responds to the information needs of a diverse, international grey literature community.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
A Social Networking Research Environment for Scientific Data Sharing: The D4Science Offering
No full textModern science calls for innovative practices to facilitate research collaborations that span institutions, disciplines, and countries. Scientists and practitioners are called to produce enhanced forms of scientific communication thus to make it possible for others to identify errors, to support, reject or refine theories and to reuse data for further understanding and knowledge. This scenario can benefit a lot from Internet-based services aiming at providing individual users having at their disposal scarce resources with interaction-oriented facilities, i.e., social computing, and elastic access to facilities on demand, i.e., cloud computing. In this paper, we present the D4Science approach that by leveraging social computing and cloud computing realises an integrated web-based working environment where scientists have at their fingertips what is needed to accomplish a scientific investigation. In particular, we present the large array of collaboration-oriented facilities obtained by integrating social networking paradigms with virtual research environments.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
Comportement à la rupture et caractérisation mécanique des caoutchoucs cristallisants sous contrainte
No full textL'objet du travail exposé dans ce mémoire de thèse de Doctorat est d'obtenir une loi de comportement anisotrope représentative de la cristallisation sous contrainte dans le caoutchouc, de l'intégrer dans un calcul macroscopique éléments finis, et de comprendre l'influence de ce phénomène sur la propagation de fissures dans ce matériau par un critère de taux de restitution d'énergie. Le problème modèle qui motive cette étude est celui de l'endurance des pneumatiques. Après une introduction générale des difficultés qui se posent dans l'endurance des pneumatiques, nous rappelons en première partie quelques notions essentielles sur le cadre mécanique. La partie II est l'occasion de s'intéresser au cadre de calcul du taux de restitution d'énergie par des méthodes de dérivation par rapport au domaine. Nous proposons alors une extension formelle de ce type de méthode au cas du comportement viscoplastique. Cette extension est proposée dans un premier cas où les processus dissipatifs et le processus de rupture sont découplés. Elle est alors testée et validée par différences finies sur des cas de calculs élastoplastiques. On propose ensuite une méthode de calcul du taux de restitution d'énergie dans le cas couplé par un état adjoint. Cette méthode est testée sur un problème viscoélastique simple. Dans la partie III, on se propose de construire une loi de comportement constitutive de la cristallisation sous contrainte. Le point de départ est une analyse microscopique que l'on passe à l'échelle macroscopique dans le cadre du modèle de micro-sphère qui nous permet de caractériser la relation contrainte-déformation, l'anisotropie des réponses locales et les effets localement induits par la cristallisation en fond de fissure. Cette construction se fonde sur des observations expérimentales de base en insistant sur les aspects constitutifs du comportement cyclique. La loi obtenue est ensuite comparée à plusieurs mesures expérimentales sur un panel exhaustif de chargements. Cela nous permet de montrer une bonne reproductibilité des résultats expérimentaux notamment en ce qui concerne les chargements cycliques et l'évolution de l'anisotropie. Pour finir, la partie IV aborde le problème de l'impact de la cristallisation sur la rupture du caoutchouc par les méthodes proposées dans les deux parties précédentes. On montre alors qu'on peut obtenir un profil de fissure et une zone cristallisée très semblable à ceux obtenus expérimentalement. De plus, l'extension du taux de restitution d'énergie proposée est appliquée à une éprouvette Pure Shear présentant de la cristallisation. L'évolution du taux de restitution d'énergie avec le chargement appliqué à l'éprouvette est alors comparée à l'évolution de la vitesse de propagation en fatigue.The following Ph D dissertation first objective is to develop a tractable anisotropic constitutive equation for strain induced-crystallizing rubber. This equation is developed at a microscopic level and then intergrated in a macroscopic framework in a finite element code. Finally the influence of strain induced crystallization on crack propagation is assessed using an associated energy release rate. The underlying goal of this study is to address the problem of tyres' endurance. After introducing the difficulties linked to tyres' endurance, basic notions on the mechanical framework at play are introduced in the first part. Part II deals with energy release rate calculations using domain's derivation methods. We then propose a formal extension of this kind of method to viscoplastic behaviour. A first case is treated where dissipative processes and failure mechanisms are uncoupled. This extension is then tested and validated on cases of elastoplastic computations. Another method to calculate the energy release rate in the coupled case is constructed using an adjoint state. This is then tested with a simple viscoelastic problem. The purpose of part III is to construct a constitutive equation for strain induced crystallizing rubber in a micro-sphere framework, so that it is possible to chararacterize stress strain relation, anisotropy of the local response and effects of crystallization at the crack tip. The approach is based on state-of-the-art experimental observations, with emphasis on the constitutive aspects of cyclic behaviour. The constitutive law is then compared with many experimental measurements, for a large panel of loading characteristics. It is shown that experimental data are well reproduced, especially these where cyclic loading and anisotropy evolution are at play. Finally, part IV deals with impact of crystallization on rubber failure, using the methods introduced in the two previous parts. The predicted failure profile and crystallized zone are quite similar to data retrieved from experiments. Moreover, the proposed extension of the energy release rate has been applied to a pure shear test sample where crystallization is happening. The evolution of energy release rate with loading is then compared to the evolution of crack propagation speed in fatigue.PALAISEAU-Polytechnique (914772301) / SudocSudocFranceF
Analyse multi-angulaire polarimétrique du site archéologique de Samarra à partir des capteurs spatiaux RADARSAT-2 et ALOS PALSAR
No full textCette recherche a pour objectif d'étudier l'impact des micro-ondes sur des structures archéologiques toujours visibles de l'ancienne cité de Samarra, la capitale de l'ancien Abbasside Califat situé en Iraq. Trois zones ont été sélectionnées pour cette recherche Doctorale : une cité octogonale, trois champs de courses et la cité de al-Mutawakkiliyya. Les menaces à lesquelles le site est exposé et son importance historique ont permis d'inscrire la cité sur la liste UNESCO des sites en danger (2007). Cela a donné une raison de plus pour enquêter sur cette zone au moyen des capteurs SAR RADARSAT-2 et ALOS PALSAR. Le potentiel de l'imagerie SAR, en fait, est bien connu, en particulier pour les régions du Monde où des enquêtes in situ ne sont pas autorisées en raison de l'instabilité politique (comme dans le cas de Samarra) et en raison de la possibilité d'acquérir quelque soit la couverture nuageuse et dans tout genre d'illumination (jour / nuit).This work has as goal to study the microwaves behavior over the archaeological structures still visible in the historical city of Samarra, the capital of the ancient Abbasid Caliphate located in Iraq. Three areas were taken into account for the Ph.D. research: an octagonal city, three racecourses stadiums and the city of al-Mutawakkiliyya. Threats to which the site is exposed and its historical importance let the city to be inscribed in the list of UNESCO sites in danger (2007). This gave a reason more to investigate this area by means of SAR RADARSAT-2 and ALOS PALSAR satellites. SAR potentiality, in fact, is well known, in particular for those areas of the World where surveys in situ are not allowed because of political instability (as in the case of Samarra) and because of the possibility of acquiring with any cloud cover conditions and in any kind of illumination (day/night).RENNES1-Bibl. électronique (352382106) / SudocSudocFranceF