982 resultados para ELECTRONIC FUNDS TRANSFER


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Au Niger, le taux de mortalité maternelle est estimé à 535 décès pour 100 000 naissances vivantes (INS, 2013) et la probabilité pour un nouveau-né de mourir avant l’âge d’un mois est de 33 ‰. Depuis 2006, le Niger a mis en place une politique de gratuité des soins pour les femmes enceintes et les enfants de 0 à 5 ans, ce qui a contribué à une amélioration significative de la fréquentation des centres de santé. En mars 2012, un processus délibératif fut organisé pendant une conférence de trois jours pour échanger sur les acquis, limites et perspectives de cette nouvelle politique avec 160 participants dont des chercheurs, des humanitaires, des décideurs politiques et des intervenants sur le terrain. L’objectif de cette recherche est de comprendre les effets de cette conférence ainsi que d’explorer les activités du comité de suivi de la feuille de route. La recherche a été réalisée durant deux mois en été 2014 à Niamey et à N’guiguimi. Elle a reposé sur l’utilisation du cadre conceptuel de Boyko et al., (2012) qui permet de décrire les principales caractéristiques et les effets attendus des dialogues délibératifs et comprendre comment les dialogues délibératifs peuvent contribuer à l’élaboration de politiques sur la base de données probantes. Nous avons mis un accent particulier sur les trois formes d’utilisation des connaissances présentées par Dagenais et al., (2013) : instrumentale, conceptuelle et persuasive. Des entretiens semi-directifs ont été effectués avec 22 acteurs impliqués dans la mise en oeuvre des recommandations. Ils ont été enregistrés, retranscrits intégralement et traités avec le logiciel QDA Miner. Les résultats de l’analyse des discours recueillis révèlent une utilisation instrumentale des recommandations et plus visible chez les humanitaires que les décideurs et les acteurs de la société civile. Il ressort aussi de cette analyse une utilisation conceptuelle et persuasive des recommandations à un degré plus faible parmi tous les acteurs. Le comité de suivi de la feuille route de la conférence n’a pratiquement pas fonctionné, par conséquent, le processus n’a pas eu l’impact souhaité. Les principales raisons de cet échec sont liées au contexte de mise en oeuvre des recommandations (arrestation de plusieurs agents du ministère de la Santé publique qui sont des membres clés du comité de suivi à cause du détournement des fonds GAVI, manque de volonté technique et politique) et/ou aux conditions financières (absence de primes pour les membres du comité et de budget de fonctionnement.). Les iv résultats obtenus ont permis de comprendre les énormes défis (contextuels, financiers notamment) qui restent à relever en matière de transfert de connaissance dans le secteur de santé publique au Niger. En ce qui concerne la suite de la conférence, il faudrait accélérer la redynamisation du comité de suivi en le dotant d’un fonds de fonctionnement et en créant une agence autonome de gestion de la gratuité des soins; et renforcer le soutien politique autour de l’Initiative Santé Solidarité Sahel.

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The introduction of electronically-active heteroanions into polyoxometalates (POMs) is one of the emerging topics in this field. The novel clusters have shown unprecedented intramolecular electron-transfer features that can be directly mediated by the incorporated heteroanions. In this thesis, we will focus on the study of phosphite (HPO32-) as new non-traditional heteroanions, discover HPO32- templated nanostructures, investigate their electronic behaviours as well as understand the self-assembly process of HPO32--templated species. The thesis starts with incorporating HPO32- into POM cages. The feasibility of this work was illustrated by the successful trapping of HPO32- into a “Trojan Horse” type {W18O56} nanocage. The reactivity of embedded {HPO3} was fully studied, showing the cluster undergoes a structural rearrangement in solution whereby the {HPO3} moieties dimerise to form a weakly interacting (O3PH···HPO3) moiety. In the crystalline state a temperature-dependent intramolecular redox reaction and structural rearrangement occurs. This rearrangement appears to proceed via an intermediate containing two different templates, a pyramidal {HPO3} and a tetrahedral {PO4} moiety. {HPO3} templated POM cages were then vigorously expanded and led to the isolation of five either fully oxidised or mixed-valence clusters trapped with mono-, di-, or tri- {HPO3}. Interestingly, an intriguing 3D honeycomb-like host-guest structure was also synthesised. The porous framework was self-aggregated by a tri-phopshite anion templated {W21} cluster with a {VO4} templated Wells-Dawson type {W18} acting as a guest species within the hexagonal channels. Based on this work, we further extended the templating anions to two different redox-active heteroanions, and discovered a unique mixed-heteroatom templated system built by pairing redox-active {HPIIIO3} with {TeO3}, {SeO3} or {AsO3}. Two molecular systems were developed, ie. “Trojan Horse” type [W18O56(HPO3)0.8(SeO3)1.2(H2O)2]8- and cross-shaped [H4P4X4W64O224]32-/36-, where X=TeIV, SeIV, AsIII. In the case of {W18(HPO3)0.8(SeO3)1.2}, the compound is found to be a mixture of heteroleptic {W18(HPO3)(SeO3)} and homoleptic {W18(SeO3)2} and {W18(HPO3)2}, identified by single crystal x-ray diffraction, NMR as well as high resolution mass spectrometry. The cluster exhibited similar temperature-dependent electronic features to “Trojan Horse” type {W18(HPO3)2O56}. However, due to the intrinsic reactivity difference between {HPO3} and {SeO3}, the thermal treatment leads to the formation of an unusual species [W18O55(PO4)(SeO3)]5-, in which {HPO3} was fully oxidised to {PO4} within the cage, whereas and lone-pair-containing {SeO3} heteroanions were kept intact inside the shell. This finding is extremely interesting, as it demonstrated that multiple and independent intramolecular electronic performance can be achieved by the coexistence of distinct heteroatoms within a single molecule. On the other hand, the cross-shaped [H4P4X4W64O224]32-/36- were constructed by four {W15(HPO3)(XO3)} building units linked by four {WO6} octahedra. Each building unit traps two different heteroatoms. It is interesting to note that the mixed heteroatom species show self-sorting, with a highly selective positional preference. Smaller ionic sized {HPO3} are self-organised into the uncapped side of {W15} cavity, whereas closed side are occupied by larger heteroatoms, which is surprisingly opposed to steric hindrance. Density functional theory (DFT) calculations are currently underway to have a full understanding of the preference of heteroatom substitutions. This series of clusters is of great interest in terms of achieving single molecule-based heteroatom-dependent multiple levels of electron transfer. It has opened a new way to design and synthesise POMs with higher diversity of electrical states, which may lead to a new type of Q-bits for quantum computing. The third chapter is focused on developing polyoxotungstate building blocks templated by {HPO3}. A series of building blocks, {W15O48(HPO3)2}, {W9O30(HPO3)} {W12O40(HPO3)2} and hexagonal {W6O18(HPO3)} have been obtained. The first four building blocks have been reported with {SeO3} and/or {TeO3} heteroanions. This result demonstrates {HPO3} has a similar reactivity as {SeO3} and {TeO3}, therefore studying the self-assembly of {HPO3}-based building blocks would be helpful to have a general understanding of pyramidal heteroatom-based molecular systems. The hexagonal {W6O18(HPO3)} is observed for the first time in polyoxotungstates, showing some of reactivity difference between {HPO3} and {SeO3} and {TeO3}. Furthermore, inorganic salts and pH values have some directing influence on the formation and transformation of various building blocks, resulting in the discovery of a family of {HPO3}-based clusters with nuclearity ranging from {W29} to {W106}. High resolution mass spectrometry was also carried out to investigate the cluster solution behaviour and also gain information of building block speciation. It is found that some clusters experienced decomposition, which gives rise to potential building blocks accountable for the self-assembly.

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Developments in theory and experiment have raised the prospect of an electronic technology based on the discrete nature of electron tunnelling through a potential barrier. This thesis deals with novel design and analysis tools developed to study such systems. Possible devices include those constructed from ultrasmall normal tunnelling junctions. These exhibit charging effects including the Coulomb blockade and correlated electron tunnelling. They allow transistor-like control of the transfer of single carriers, and present the prospect of digital systems operating at the information theoretic limit. As such, they are often referred to as single electronic devices. Single electronic devices exhibit self quantising logic and good structural tolerance. Their speed, immunity to thermal noise, and operating voltage all scale beneficially with junction capacitance. For ultrasmall junctions the possibility of room temperature operation at sub picosecond timescales seems feasible. However, they are sensitive to external charge; whether from trapping-detrapping events, externally gated potentials, or system cross-talk. Quantum effects such as charge macroscopic quantum tunnelling may degrade performance. Finally, any practical system will be complex and spatially extended (amplifying the above problems), and prone to fabrication imperfection. This summarises why new design and analysis tools are required. Simulation tools are developed, concentrating on the basic building blocks of single electronic systems; the tunnelling junction array and gated turnstile device. Three main points are considered: the best method of estimating capacitance values from physical system geometry; the mathematical model which should represent electron tunnelling based on this data; application of this model to the investigation of single electronic systems. (DXN004909)

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The electronic conduction of thin-film field-effect-transistors (FETs) of sexithiophene was studied. In most cases the transfer curves deviate from standard FET theory; they are not linear, but follow a power law instead. These results are compared to conduction models of "variable-range hopping" and "multi-trap-and-release". The accompanying IV curves follow a Poole-Frenkel (exponential) dependence on the drain voltage. The results are explained assuming a huge density of traps. Below 200 K, the activation energy for conduction was found to be ca. 0.17 eV. The activation energies of the mobility follow the Meyer-Neldel rule. A sharp transition is seen in the behavior of the devices at around 200 K. The difference in behavior of a micro-FET and a submicron FET is shown. (C) 2004 American Institute of Physics.

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A wide range of non-destructive testing (NDT) methods for the monitoring the health of concrete structure has been studied for several years. The recent rapid evolution of wireless sensor network (WSN) technologies has resulted in the development of sensing elements that can be embedded in concrete, to monitor the health of infrastructure, collect and report valuable related data. The monitoring system can potentially decrease the high installation time and reduce maintenance cost associated with wired monitoring systems. The monitoring sensors need to operate for a long period of time, but sensors batteries have a finite life span. Hence, novel wireless powering methods must be devised. The optimization of wireless power transfer via Strongly Coupled Magnetic Resonance (SCMR) to sensors embedded in concrete is studied here. First, we analytically derive the optimal geometric parameters for transmission of power in the air. This specifically leads to the identification of the local and global optimization parameters and conditions, it was validated through electromagnetic simulations. Second, the optimum conditions were employed in the model for propagation of energy through plain and reinforced concrete at different humidity conditions, and frequencies with extended Debye's model. This analysis leads to the conclusion that SCMR can be used to efficiently power sensors in plain and reinforced concrete at different humidity levels and depth, also validated through electromagnetic simulations. The optimization of wireless power transmission via SMCR to Wearable and Implantable Medical Device (WIMD) are also explored. The optimum conditions from the analytics were used in the model for propagation of energy through different human tissues. This analysis shows that SCMR can be used to efficiently transfer power to sensors in human tissue without overheating through electromagnetic simulations, as excessive power might result in overheating of the tissue. Standard SCMR is sensitive to misalignment; both 2-loops and 3-loops SCMR with misalignment-insensitive performances are presented. The power transfer efficiencies above 50% was achieved over the complete misalignment range of 0°-90° and dramatically better than typical SCMR with efficiencies less than 10% in extreme misalignment topologies.

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Today, modern System-on-a-Chip (SoC) systems have grown rapidly due to the increased processing power, while maintaining the size of the hardware circuit. The number of transistors on a chip continues to increase, but current SoC designs may not be able to exploit the potential performance, especially with energy consumption and chip area becoming two major concerns. Traditional SoC designs usually separate software and hardware. Thus, the process of improving the system performance is a complicated task for both software and hardware designers. The aim of this research is to develop hardware acceleration workflow for software applications. Thus, system performance can be improved with constraints of energy consumption and on-chip resource costs. The characteristics of software applications can be identified by using profiling tools. Hardware acceleration can have significant performance improvement for highly mathematical calculations or repeated functions. The performance of SoC systems can then be improved, if the hardware acceleration method is used to accelerate the element that incurs performance overheads. The concepts mentioned in this study can be easily applied to a variety of sophisticated software applications. The contributions of SoC-based hardware acceleration in the hardware-software co-design platform include the following: (1) Software profiling methods are applied to H.264 Coder-Decoder (CODEC) core. The hotspot function of aimed application is identified by using critical attributes such as cycles per loop, loop rounds, etc. (2) Hardware acceleration method based on Field-Programmable Gate Array (FPGA) is used to resolve system bottlenecks and improve system performance. The identified hotspot function is then converted to a hardware accelerator and mapped onto the hardware platform. Two types of hardware acceleration methods – central bus design and co-processor design, are implemented for comparison in the proposed architecture. (3) System specifications, such as performance, energy consumption, and resource costs, are measured and analyzed. The trade-off of these three factors is compared and balanced. Different hardware accelerators are implemented and evaluated based on system requirements. 4) The system verification platform is designed based on Integrated Circuit (IC) workflow. Hardware optimization techniques are used for higher performance and less resource costs. Experimental results show that the proposed hardware acceleration workflow for software applications is an efficient technique. The system can reach 2.8X performance improvements and save 31.84% energy consumption by applying the Bus-IP design. The Co-processor design can have 7.9X performance and save 75.85% energy consumption.

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Transportation research makes a difference for Iowans and the nation. Implementation of cost effective research projects contributes to a transportation network that is safer, more efficient, and longer lasting. Working in cooperation with our partners from universities, industry, other states, and FHWA, as well as participation in the Transportation Research Board (TRB), provides benefits for every facet of the DOT. This allows us to serve our communities and the traveling public more effectively. Pooled fund projects allow leveraging of funds for higher returns on investments. In 2010, Iowa led fifteen active pooled fund studies, participated in twenty-two others, and was wrapping-up, reconciling, and closing out an additional 6 Iowa Led pooled fund studies. In addition, non-pooled fund SPR projects included approximately 20 continued, 9 new, and over a dozen reoccurring initiatives such as the technical transfer/training program. Additional research is managed and conducted by the Office of Traffic and Safety and other departments in the Iowa DOT.

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This paper presents a study related with measuring of radio frequency emissions. The purpose is to determine the level of interference generated by wireless power transfer equipment in a specific frequency range, and to compare those levels to the existing standards. The technology of wireless power transfer, especially for electric vehicles batteries charging, is rapidly developing in the recent years. An increasing use of this technology in industrial and consumer electronic products has raised concerns about the possible unfavorable health-effects onto the human being. Another concern is raised from the high intensity fields produced by wireless power transfer systems which will generate highly undesired influence on other electrical and electronic equipment. As a protection against the potential health effects, the governments imposed limits on the occupational and general public exposure to the radio frequencies. These limitations are set out in national and international safety guidelines, standards and regulations. The measurement and evaluation of the human exposure to electromagnetic fields are essential to guarantee occupational and general public safety.

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Two dimensional flow of a micropolar fluid in a porous channel is investigated. The flow is driven by suction or injection at the channel walls, and the micropolar model due to Eringen is used to describe the working fluid. An extension of Berman's similarity transform is used to reduce the governing equations to a set of non-linear coupled ordinary differential equations. The latter are solved for large mass transfer via a perturbation analysis where the inverse of the cross-flow Reynolds number is used as the perturbing parameter. Complementary numerical solutions for strong injection are also obtained using a quasilinearisation scheme, and good agreement is observed between the solutions obtained from the perturbation analysis and the computations.

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Visible, near-infrared, IR and Raman spectra of magnesian gaspeite are presented. Nickel ion is the main source of the electronic bands as it is the principal component in the mineral where as the bands in IR and Raman spectra are due to the vibrational processes in the carbonate ion as an entity. The combination of electronic absorption and vibrational spectra (including near-infrared, FTIR and Raman) of magnesian gaspeite are explained in terms of the cation co-ordination and the behaviour of CO32– anion in the Ni–Mg carbonate. The electronic absorption spectrum consists of three broad and intense bands at 8130, 13160 and 22730 cm–1 due to spin-allowed transitions and two weak bands at 20410 and 30300 cm–1 are assigned to spin-forbidden transitions of Ni2+ in an octahedral symmetry. The crystal field parameters evaluated from the observed bands are Dq = 810; B = 800 and C = 3200 cm–1. The two bands in the near-infrared spectrum at 4330 and 5130 cm–1 are overtone and combination of CO32– vibrational modes. For the carbonate group, infrared bands are observed at 1020 cm–1(1 ), 870 cm–1 (2), 1418 cm–1 (3) and 750 cm–1 (4), of which3, the asymmetric stretching mode is most intense. Three well resolved Raman bands at 1571, 1088 and 331 cm–1 are assigned to 3, 1 and MO stretching vibrations.