1,999 research outputs found

    Electric road vehicles - overview, concepts and research at Reutlingen university

    Get PDF
    The paper details the architecture of fully electrified vehicles as well as their new electronic systems. Examples of up-to-date electrical passenger cars are given. A very important question, that is the environmental foot-print of electrical vehicles compared to conventional ones, is examined. A research project is introduced where a fleet of two-wheeled vehicles is available for day-to-day use. Research on vehicles, software for fleet management and battery range prediction is described.В данной статье привeдены подробные сведения о принципе работы электрифицированных транспортных средств, а также описаны их новые электрические системы. Показан примеры уже существующих электрических пассажирских транспортных средств. Рассмотрено влияние электрифицированного транспорта на окружающую среду в сравнении с обычными видами транспорта. Приведен проект исследований, в рамках которого для ежедневного использования существует парк двух колесных электрифицированных транспортных средств. Описаны исследования, непосредственно связанные с электрифицированным транспортом, определением точного времени разряда батареи, а также программным обеспечением, позволяющим управлять парком таких транспортных средств.У статті наведено докладні відомості щодо принципів роботи електрифікованих транспортних засобів, а також описано їх нові електричні системи. Показано приклади вже існуючих електричних пасажирських транспортних засобів. Розглянуто вплив електрифікованого транспорту на навколишнє середовище у порівнянні із звичайними видами транспорту. На- ведено проект досліджень, у рамках якого існує парк двоколісних електрифікованих транспортних засобів для щоденного використання. Описано дослідження, безпосередньо пов'язані із електрифікованим транспортом, визначенням точного часу розряду батареї, а також програмним забезпеченням, що дозволяє керувати парком таких транспортних засобів

    Micro-mechanical sensor for the spectral decomposition of acoustic signals

    Get PDF
    An array of electret-biased frequency-selective resonant microelectromechanical system (MEMS) acoustic sensors was proposed to perform analysis of stress pulses created during an impact between two materials. This analysis allowed classification of the stiffness of the materials involved in the impact without applying post-impact signal processing. Arrays of resonant MEMS sensors provided filtering of the incident stress pulse and subsequent binning of time-domain waveforms into frequency-based spectra. Results indicated that different impact conditions and materials yielded different spectral characteristics. These characteristics, as well as the resulting sensor array responses, are discussed and applied to impact classification. Each individual sensor element in the array was biased by an in situ charged electret film. A microplasma discharge apparatus embedded within the microsensor allowed charging of the electret film after all device fabrication was complete. This enabled electret film integration using high-temperature surface micromachining processes that would typically lead to discharge of traditionally formed electret materials. This also eliminated the traditional wafer-bonding and post-fabrication assembly processes required in conventional electret integration approaches. The microplasma discharge process and resulting electret performance are discussed within the context of the MEMS acoustic sensor array.Ph.D.Committee Chair: Allen, Mark; Committee Member: Brand, Oliver; Committee Member: Michaels, Jennifer; Committee Member: Michaels, Thomas; Committee Member: Ready, Jud W

    Benchmarking high fidelity single-shot readout of semiconductor qubits

    Full text link
    Determination of qubit initialisation and measurement fidelity is important for the overall performance of a quantum computer. However, the method by which it is calculated in semiconductor qubits varies between experiments. In this paper we present a full theoretical analysis of electronic single-shot readout and describe critical parameters to achieve high fidelity readout. In particular, we derive a model for energy selective state readout based on a charge detector response and examine how to optimise the fidelity by choosing correct experimental parameters. Although we focus on single electron spin readout, the theory presented can be applied to other electronic readout techniques in semiconductors that use a reservoir.Comment: 19 pages, 8 figure

    Dark matter within high surface brightness spiral galaxies

    Get PDF
    We present results from a detailed dynamical analysis of five high surface brightness, late type spirals, studied with the aim to quantify the luminous-to-dark matter ratio inside their optical radii. The galaxies' stellar light distribution and gas kinematics have been observed and compared to hydrodynamic gas simulations, which predict the 2D gas dynamics arising in response to empirical gravitational potentials, which are combinations of differing stellar disk and dark halo contributions. The gravitational potential of the stellar disk was derived from near-infrared photometry, color-corrected to constant (M/L); the dark halo was modelled by an isothermal sphere with a core. Hydrodynamic gas simulations were performed for each galaxy for a sequence of five different mass fractions of the stellar disk and for a wide range of spiral pattern speeds. These two parameters mainly determine the modelled gas distribution and kinematics. The agreement between the non-axisymmetric part of the simulated and observed gas kinematics permitted us to conclude that the galaxies with the highest rotation velocities tend to possess near-maximal stellar disks. In less massive galaxies, with v_max<200 km/s, the mass of the dark halo at least equals the stellar mass within 2-3 R_disk. The simulated gas morphology provides a powerful tool to determine the dominant spiral pattern speed. The corotation radius for all galaxies was found to be constant at R_corotation ~ 3 R_disk and encloses the strong part of the stellar spiral in all cases.Comment: 28 pages, 7 figures; to appear in the Astrophysical Journal, Vol. 586, March 200
    corecore