2,851 research outputs found

    Review of ADCs for imaging

    Get PDF
    The aim of this article is to guide image sensors designers to optimize the analog-to-digital conversion of pixel outputs. The most common ADCs topologies for image sensors are presented and discussed. The ADCs specific requirements for these sensors are analyzed and quantified. Finally, we present relevant recent contributions of specific ADCs for image sensors and we compare them using a novel FOM. © (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use onlyPeer reviewe

    A high dynamic range image sensor with linear response based on asynchronous event detection

    Get PDF
    This paper investigates the potential of an image sensor that combines event-based asynchronous outputs with conventional integration of photocurrents. Pixels voltages can be read out following a traditional approach with a source follower and analog-to-digital converter. Furthermore, pixels have circuitry to implement Pulse Density Modulation (PDM) sending out pulses with a frequency that is proportional to the photocurrent. Both read-out approaches operate simultaneously. Their information is combined to render high dynamic range images. In this paper, we explain the new vision sensor concept and we develop a theoretical analysis of the expected performance in standard AMS 0.18mm HV technology. Moreover, we provide a description of the vision sensor architecture and its main blocksPeer reviewe

    Determination of Optimal Grazing Management for Dairy Cows in Galicia (Spain) Using a Decision Support System

    Get PDF
    GRAZEMORE is a decision support system (DSS) oriented to evaluate dairy grazing management decisions on pasture growth and milk production. The system integrates a herbage growth model (Barrett et al., 2003) and a herbage intake model (Delagarde et al., 2004) and has been validated in several EU countries. The objective of this work was to use this DSS to determine optimal grazing management of dairy cows at three supplementation levels and three grazing management strategies under Galician conditions

    Field-induced magnetic anisotropy in La0.7Sr0.3CoO3

    Full text link
    Magnetic anisotropy has been measured for the ferromagnetic La0.7Sr0.3CoO3 perovskite from an analysis of the high-field part of the magnetization vs. field curves, i.e., the magnetic saturation regime. These measurements give a magnetic anistropy one order of magnitude higher than that of reference manganites. Surprisingly, the values of the magnetic anisotropy calculated in this way do not coincide with those estimated from measurements of coercive fields which are one order of magnitude smaller. It is proposed that the reason of this anomalous behaviour is a transition of the trivalent Co ions under the external magnetic field from a low-spin to an intermediate-spin state. Such a transition converts the Co3+ ions into Jahn-Teller ions having an only partially quenched orbital angular momentum, which enhances the intra-atomic spin-orbit coupling and magnetic anisotropy.Comment: Accepted of publication in Europhysics Letters, 11 pages, 5 figure

    Modifications in the distribution of met-enkephalin in the cat spinal cord after administration of clonidine. An immunocytochemical study

    Get PDF
    We have studied the modifications in the distribution of methionine-enkephalin in the cat spinal cord after intravenous or intrathecal administration of clonidine by using an immunocytochemical technique. In animals not treated with the substance, a very high density of immunoreactive fibers was found in layers I and 11; a high density in the dorso-lateral funiculus and in the reticular formation; a moderate density in layers 111, IV and V; and a low density in layer VI. However, after intravenous or intrathecal administration of clonidine a decrease in fibers containing met-enkephalin was observed in layers I and I1 (high or moderate density), the dorso-lateral funiculus, and the reticular formation (moderate or low density), and in layers IV and V (low or very low density). In all cases, the decrease in the immunoreactivity was more marked when clonidine was administered intrathecally. Our results suggest that clonidine induces the release of metenkephalin in the spinal cord. They further suggest that the opioid peptide released could be involved in the control of nociceptive transmission by inhibiting the release of neurotransmitters (e.g., substance P). In summary, our study shows that clonidine could be involved in antinociceptive mechanisms in the cat spinal cord
    corecore