1,948 research outputs found

    Design of an Auxiliary Power Distribution Network for an Electric Vehicle

    Get PDF
    This paper presents the design of an auxiliary power distribution network for an electric vehicle. Efficiency is a key element in the design for any electric vehicle and a 48Vdc distribution network will be used throughout the vehicle. The high efficiency Cuk converter has been selected as the most appropriate topology to supply the various distributed loads. To achieve the best compromise between efficiency and component sizes, a switching frequency of 100kHz is used. The results from simulations and experimental measurements are discussed and a range of proposals is also made to modify some of the existing loads to further improve efficiency

    3-loop heavy flavor Wilson coefficients in deep-inelastic scattering

    Full text link
    We present our most recent results on the calculation of the heavy flavor contributions to deep-inelastic scattering at 3-loop order in the large Q2Q^2 limit, where the heavy flavor Wilson coefficients are known to factorize into light flavor Wilson coefficients and massive operator matrix elements. We describe the different techniques employed for the calculation and show the results in the case of the heavy flavor non-singlet and pure singlet contributions to the structure function F2(x,Q2)F_2(x,Q^2).Comment: 4 pages Latex, 2 style files, 4 Figures, Contribution to the Proceedings of QCD '14, Montpellier, Jult 201

    Measuring the activity of European and African Countries using Social Accounting Matrices

    Get PDF
    Economic models at the micro, meso and macro levels presuppose the existence of consistent databases that make it possible to quantify the activity of enterprises, sectors, regions, countries or continents. Such models can also be important aids in the policy decision process, since they permit the construction of scenarios resulting from the adoption of policy measures and the consequent changes that they introduce. When consistent with the United Nations System of National Accounts (SNA), the Social Accounting Matrix (SAM) can include all the nominal flows of the measured part of the economy, at the level of both production and the institutions, and therefore satisfies these requirements. Thus, in its numerical version, a SAM constitutes a database and provides a snapshot of the measured reality at a certain moment, whereas its possible algebraic versions, i.e. models that are based upon it, permit the construction of the above-mentioned scenarios. The possibility and usefulness of constructing SAMs for African countries consistent with the SNA will be examined and experimented. The SAM’s basic structure and consistency within the whole system will be studied, as well as any possible disaggregations, extensions, aggregates, indicators and balances that can be calculated. Other aspects beyond that basic structure will also be examined in order to show to what extent the SAM is capable of covering parts of the economy that are not covered by the SNA.info:eu-repo/semantics/publishedVersio

    Electroluminescence from single nanowires by tunnel injection: an experimental study

    Get PDF
    We present a hybrid light-emitting diode structure composed of an n-type gallium nitride nanowire on a p-type silicon substrate in which current is injected along the length of the nanowire. The device emits ultraviolet light under both bias polarities. Tunnel-injection of holes from the p-type substrate (under forward bias) and from the metal (under reverse bias) through thin native oxide barriers consistently explains the observed electroluminescence behaviour. This work shows that the standard p-n junction model is generally not applicable to this kind of device structure.Comment: 6 pages, 6 figure

    Socio-economic studies with social accounting and sociodemographic matrices : an application to Portugal.

    Get PDF
    In looking for empirical evidence about the activity of countries, a proposal is made for studying (measuring and modelling) the activity of countries through the use of Social Accounting Matrices (SAMs) and Socio-Demographic Matrices (SDMs). SAMs and SDMs are presented as tools that have specific features for conducting studies in several different areas, as well as for supporting policy decision processes. Based on methodological principles that are derived mainly from the works of Richard Stone, emphasis is placed on the desirability of working in a matrix format, which includes not only people (SDM), but also, at the same time, activities, products, factors of production and institutions (SAM). This is considered to be a way of capturing the relevant network of linkages and the corresponding multiplier effects, which can be used for the subsequent modelling of the activity of the countries studied. A method will be proposed for the construction of these matrices. In the case of the SAMs, it is proposed that their design and construction should adopt, at least as their starting point, the latest version of the System of National Accounts (2008 SNA) and the corresponding results of its adoption/adaptation by different countries. The exposition of this proposal is accompanied by an example applied to Portugal.Financial support provided by FCT (Fundação para a Ciência e a Tecnologia)Portugal for the research and writing of this article, which forms part of the Strategic Project for 2011-13 (PEst- OE/EGE/UI0436/2011)

    CoMPASs: IOn programme (Care Of Memory Problems in Advanced Stages of dementia: Improving Our Knowledge): protocol for a mixed methods study

    Get PDF
    Approximately 700 000 people in the UK have dementia, rising to 1.2 million by 2050; one-third of people aged over 65 will die with dementia. Good end-of-life care is often neglected, and detailed UK-based research on symptom burden and needs is lacking. Our project examines these issues from multiple perspectives using a rigorous and innovative design, collecting data which will inform the development of pragmatic interventions to improve care

    Evolution of the Plant Reproduction Master Regulators LFY and the MADS Transcription Factors: The Role of Protein Structure in the Evolutionary Development of the Flower.

    Get PDF
    International audienceUnderstanding the evolutionary leap from non-flowering (gymnosperms) to flowering (angiosperms) plants and the origin and vast diversification of the floral form has been one of the focuses of plant evolutionary developmental biology. The evolving diversity and increasing complexity of organisms is often due to relatively small changes in genes that direct development. These "developmental control genes" and the transcription factors (TFs) they encode, are at the origin of most morphological changes. TFs such as LEAFY (LFY) and the MADS-domain TFs act as central regulators in key developmental processes of plant reproduction including the floral transition in angiosperms and the specification of the male and female organs in both gymnosperms and angiosperms. In addition to advances in genome wide profiling and forward and reverse genetic screening, structural techniques are becoming important tools in unraveling TF function by providing atomic and molecular level information that was lacking in purely genetic approaches. Here, we summarize previous structural work and present additional biophysical and biochemical studies of the key master regulators of plant reproduction - LEAFY and the MADS-domain TFs SEPALLATA3 and AGAMOUS. We discuss the impact of structural biology on our understanding of the complex evolutionary process leading to the development of the bisexual flower

    Perioperative passport: empowering people with diabetes along their surgical journey

    Get PDF
    © 2017 Diabetes UK Aim: To determine whether a handheld ‘perioperative passport’ could improve the experience of perioperative care for people with diabetes and overcome some of the communication issues commonly identified in inpatient extracts. Methods: Individuals with diabetes undergoing elective surgery requiring at least an overnight stay were identified via a customized information technology system. Those allocated to the passport group were given the perioperative passport before their hospital admission. A 26-item questionnaire was completed after surgery by 50 participants in the passport group (mean age 69 years) and by 35 participants with diabetes who followed the usual surgical pathway (mean age 70 years). In addition, the former group had a structured interview about their experience of the passport. Results: The prevalence of those who reported having received prior information about their expected diabetes care was 35% in the control group vs 92% in the passport group (
    corecore