3,410 research outputs found
Elastic-DF: Scaling Performance of DNN Inference in FPGA Clouds through Automatic Partitioning
No full textCustomized 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
Activation of the Notch pathway in Down syndrome: cross-talk of Notch and APP.
No full textABSTRACT Down syndrome (DS) patients suffer
from mental retardation, but also display enhanced
-APP production and develop cortical amyloid
plaques at an early age. As -APP and Notch are both
processed by -secretase, we analyzed expression of the
Notch signaling pathway in the adult DS brain and in a
model system for DS, human trisomy 21 fibroblasts by
quantitative PCR. In adult DS cortex we found that
Notch1, Dll1 and Hes1 expression is up-regulated.
Moreover, DS fibroblasts and Alzheimer disease cortex
also show overexpression of Notch1 and Dll1, indicating
that enhanced -APP processing found in both DS
and AD could be instrumental in these changes. Using
pull-down studies we could demonstrate interaction of
APP with Notch1, suggesting that these transmembrane
proteins form heterodimers, but independent of
-secretase. We could demonstrate binding of the intracellular
domain of Notch1 to the APP adaptor
protein Fe65. Furthermore, activated Notch1 can transactivate
an APP target gene, Kai1, and vice versa,
activated APP can trans-activate the classical Notch
target gene Hes1. These data suggest that Notch expression
is activated in Down syndrome, possibly
through cross-talk with APP signaling. This interaction
might affect brain development, since the Notch pathway
plays a pivotal role in neuron-glia differentiation.—
Activation of the Notch pathway in Down syndrome:
cross-talk of Notch and APP. Fischer, D. F., van Dijk,
R., Sluijs, J. A., Nair, S. M., Racchi, M., Levelt, C. N.,
van Leeuwen, F. W., Hol, E. M. FASEB J. 19, 1451–1458
(2005
Hydrodynamical turbulence by fractal fourier decimation
No full textWe 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.'
No full textResponse by the author (Vukovich) to a review of Illiberal China (my 2019 monograph
DF AND HF LASER SPECTRA
No full textW. 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 Molecular constants derived by combining these laser measurements with other available data will be presented
OPTOACOUSTIC MEASUREMENT OF DF LASER ABSORPTION BY METHANE
No full textAuthor 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 region. Construction and calibration of the spectrophone will be discussed
Modeling and design of df/dt-based inertia control for power converters
No full textS.1553-1564Power systems with high penetration rates of inverter-based generation units exhibit reduced system inertia. Faults like plant outages or fault-induced system splits then cause an increased rate of change of frequency and may lead to frequency instability. One of the proposed schemes to provide synthetic inertia with power electronic converters is the frequency-derivative-based (df/dt) approach. Converters with this method inject an active current that is proportional to the derivative of the grid frequency to mimic the inertia of synchronous plants. Specification of synthetic inertia is currently being discussed for future grid codes. In this paper, we show that the frequency derivative in the df/dt controller is subject to a severe bandwidth limitation. Considerable low-pass filtering is indispensable to avoid instability due to the excitation of local oscillation modes in the harmonic frequency range. We have found a first-order lag with a time constant around 1 s to be required for a robustly stable system with common parameters. A new discrete-time linear model that accurately represents sampling effects is introduced and comprehensively described. A df/dt control design is proposed that leads to a robustly stable system. Model and control design are validated by laboratory experiments, especially regarding mechanisms of instability. The main finding of this paper-applying a df/dt controller harbors the risk of merely shifting the initial danger of system-wide frequency instability to local stability problems-is important for power plant manufacturers as well as system operators.5Nr.
Generalized Tukey-type distributions with application to financial and teletraffic data
No full textConstructing skew and heavy-tailed distributions by transforming a standard normal variable goes back to Tukey (1977) and was extended and formalized by Hoaglin (1983) and Martinez & Iglewicz (1984). Applications of Tukey's GH distribution family - which are composed by a skewness transformation G and a kurtosis transformation H - can be found, for instance, in financial, environmental or medical statistics. Recently, alternative transformations emerged in the literature. Rayner & MacGillivray (2002b) discuss the GK distributions, where Tukey's H-transformation is replaced by another kurtosis transformation K. Similarly, Fischer & Klein (2004) advocate the J-transformation which also produces heavy tails but - in contrast to Tukey's H-transformation - still guarantees the existence of all moments. Within this work we present a very general kurtosis transformation which nests H-, K- and J-transformation and, hence, permits to discriminate between them. Applications to financial and teletraffic data are given. --
Comparison of system architecture and converter topology for a solar powered electric vehicle charging station
No full textAccepted Author ManuscriptOld - EWI-ESE-DC&S DC systems & StoragePhotovoltaic Materials and Device
Simulation of a surface-transverse wave (STW) biosensor for DF-1 cells
No full textA 250 MHz Surface-Transverse Wave (STW) resonator is employed as a sensor element for the
detection of DF-1 cells. STW belongs to the shear-horizontal acoustic plate modes (SH-APM) waves’
family where it has attracted plenty considerable interest. STWs are horizontally polarized shear waves
which are generated and detected by the interdigital transducers (IDTs) similar to surface-acoustic wave
(SAW) resonators [1]. Detection of chemical and biological agents in aqueous solutions is a difficult
problem, especially when the detection technique has to be sensitive, power-efficient and very handy.
Acoustic plate mode is a mode of vibration where particle motion is parallel to the surface. This makes it
possible to produce a sensitive sensor capable of operating in fluids [2]. This paper presents the biosensor
prototype utilizing STW resonator
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