2,134 research outputs found

    Elastic-DF: Scaling Performance of DNN Inference in FPGA Clouds through Automatic Partitioning

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    Customized compute acceleration in the datacenter is key to the wider roll-out of applications based on deep neural network (DNN) inference. In this article, we investigate how to maximize the performance and scalability of field-programmable gate array (FPGA)-based pipeline dataflow DNN inference accelerators (DFAs) automatically on computing infrastructures consisting of multi-die, network-connected FPGAs. We present Elastic-DF, a novel resource partitioning tool and associated FPGA runtime infrastructure that integrates with the DNN compiler FINN. Elastic-DF allocates FPGA resources to DNN layers and layers to individual FPGA dies to maximize the total performance of the multi-FPGA system. In the resulting Elastic-DF mapping, the accelerator may be instantiated multiple times, and each instance may be segmented across multiple FPGAs transparently, whereby the segments communicate peer-to-peer through 100 Gbps Ethernet FPGA infrastructure, without host involvement. When applied to ResNet-50, Elastic-DF provides a 44% latency decrease on Alveo U280. For MobileNetV1 on Alveo U200 and U280, Elastic-DF enables a 78% throughput increase, eliminating the performance difference between these cards and the larger Alveo U250. Elastic-DF also increases operating frequency in all our experiments, on average by over 20%. Elastic-DF therefore increases performance portability between different sizes of FPGA and increases the critical throughput per cost metric of datacenter inference. Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Computer Engineerin

    Hydrodynamical turbulence by fractal fourier decimation

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    We present a systematic numerical investigation of high-resolution 3D isotropic and homogeneous turbulence resolved on a decimated set of Fourier modes. Fractal decimation acts to decrease the effective dimensionality of the flow by allowing triadic interactions only in a set of Fourier modes N(k) proportional to k^DF for large k. While keeping the symmetries of the original 3D Navier-Stokes equations unchanged, a dramatic change in small-scale statistics is detected at decreasing the fractal dimension DF . Already at fractal dimension DF = 2.8, a global self-similar behaviour is observed in the inertial range of scales, the consequence of such transition are the restoration of the scaling symmetry and vorticity distribution that becomes close to Gaussian. We relate the results to the different roles of local vs non-local interactions in the energy transfer range

    'Response by the author, Daniel F. Vukovich.'

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    Response by the author (Vukovich) to a review of Illiberal China (my 2019 monograph

    DF AND HF LASER SPECTRA

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    1^{1}W. B. Roh and K. Narahari Rao, J. Mol. Spectrosc. 49, 317 (1974).""Author Institution: Department of Physics, The Ohio State University; Department of Electrical Engineering, The Ohio State UniversityA pulsed laser was used as a source to study DF and HF infrared laser spectra with a grating spectrometer. The rotational structure observed for the 1-0, 2-1, and 3-2 bands of DF, and the 1-0 and 2-1 bands of HF has been measured by following a procedure similar to that used for the CO laser spectra.1spectra.^{1} Molecular constants derived by combining these laser measurements with other available data will be presented

    OPTOACOUSTIC MEASUREMENT OF DF LASER ABSORPTION BY METHANE

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    Author Institution:An optoacoustic system has been constructed for measurement of absorption of DF laser radiation. Absorption by methane in Argon and Nitrogen has been measured at 15 DF laser lines in the 3.6 – 4.0 μm\mu m region. Construction and calibration of the spectrophone will be discussed

    Experimental analysis of the flow dynamics in the suction chamber of an external gear pump

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    Time-Resolved Particle Image Velocimetry (TRPIV) has been used to investigate the flow inside the suction chamber of an external gear pump where the movement of the fluid through the pump is maintained by the rotation of the gears. The main purpose of this paper is to study the characteristics of the complex flow pattern of this pump system in order to help in improving its total performance. The applied experimental techniques establish a method that allows visualising the flow inside the gear pump with a high rotational velocity system. Small micro air bubbles have been used as flow seeding. The images have been processed using domestic PIV software that uses specific aspects of the TRPIV technique. Instantaneous and phase-locked ensemble average fluid motions have been obtained for different gear pump rotational velocities to investigate the turbulence effect of rotating gears to the system.Peer Reviewe

    Experimental analysis of the flow dynamics in the suction chamber of an external gear pump

    No full text
    Time-Resolved Particle Image Velocimetry (TRPIV) has been used to investigate the flow inside the suction chamber of an external gear pump where the movement of the fluid through the pump is maintained by the rotation of the gears. The main purpose of this paper is to study the characteristics of the complex flow pattern of this pump system in order to help in improving its total performance. The applied experimental techniques establish a method that allows visualising the flow inside the gear pump with a high rotational velocity system. Small micro air bubbles have been used as flow seeding. The images have been processed using domestic PIV software that uses specific aspects of the TRPIV technique. Instantaneous and phase-locked ensemble average fluid motions have been obtained for different gear pump rotational velocities to investigate the turbulence effect of rotating gears to the system.Peer ReviewedPostprint (published version

    Numerical analysis of the shaft motion in the journal bearing of a gear pump

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    This paper describes a numerical analysis of the dynamics of the shaft in the journal bearing of a gear pump.Peer Reviewe

    Numerical analysis of the shaft motion in the journal bearing of a gear pump

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    This paper describes a numerical analysis of the dynamics of the shaft in the journal bearing of a gear pump.Peer ReviewedPostprint (published version

    Comparison of system architecture and converter topology for a solar powered electric vehicle charging station

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    Accepted Author ManuscriptOld - EWI-ESE-DC&S DC systems & StoragePhotovoltaic Materials and Device
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