28,049 research outputs found
LEGaTO: first steps towards energy-efficient toolset for heterogeneous computing
LEGaTO is a three-year EU H2020 project which started in December 2017. The LEGaTO project will leverage task-based programming models to provide a software ecosystem for Made-in-Europe heterogeneous hardware composed of CPUs, GPUs, FPGAs and dataflow engines. The aim is to attain one order of magnitude energy savings from the edge to the converged cloud/HPC.Peer ReviewedPostprint (author's final draft
GREAT: the SOFIA high-frequency heterodyne instrument
We describe the design and construction of GREAT, the German REceiver for
Astronomy at Terahertz frequencies operated on the Stratospheric Observatory
for Infrared Astronomy (SOFIA). GREAT is a modular dual-color heterodyne
instrument for highresolution far-infrared (FIR) spectroscopy. Selected for
SOFIA's Early Science demonstration, the instrument has successfully performed
three Short and more than a dozen Basic Science flights since first light was
recorded on its April 1, 2011 commissioning flight.
We report on the in-flight performance and operation of the receiver that -
in various flight configurations, with three different detector channels -
observed in several science-defined frequency windows between 1.25 and 2.5 THz.
The receiver optics was verified to be diffraction-limited as designed, with
nominal efficiencies; receiver sensitivities are state-of-the-art, with
excellent system stability. The modular design allows for the continuous
integration of latest technologies; we briefly discuss additional channels
under development and ongoing improvements for Cycle 1 observations.
GREAT is a principal investigator instrument, developed by a consortium of
four German research institutes, available to the SOFIA users on a
collaborative basis
A Survey on Compiler Autotuning using Machine Learning
Since the mid-1990s, researchers have been trying to use machine-learning
based approaches to solve a number of different compiler optimization problems.
These techniques primarily enhance the quality of the obtained results and,
more importantly, make it feasible to tackle two main compiler optimization
problems: optimization selection (choosing which optimizations to apply) and
phase-ordering (choosing the order of applying optimizations). The compiler
optimization space continues to grow due to the advancement of applications,
increasing number of compiler optimizations, and new target architectures.
Generic optimization passes in compilers cannot fully leverage newly introduced
optimizations and, therefore, cannot keep up with the pace of increasing
options. This survey summarizes and classifies the recent advances in using
machine learning for the compiler optimization field, particularly on the two
major problems of (1) selecting the best optimizations and (2) the
phase-ordering of optimizations. The survey highlights the approaches taken so
far, the obtained results, the fine-grain classification among different
approaches and finally, the influential papers of the field.Comment: version 5.0 (updated on September 2018)- Preprint Version For our
Accepted Journal @ ACM CSUR 2018 (42 pages) - This survey will be updated
quarterly here (Send me your new published papers to be added in the
subsequent version) History: Received November 2016; Revised August 2017;
Revised February 2018; Accepted March 2018
Unsupervised Anomaly-based Malware Detection using Hardware Features
Recent works have shown promise in using microarchitectural execution
patterns to detect malware programs. These detectors belong to a class of
detectors known as signature-based detectors as they catch malware by comparing
a program's execution pattern (signature) to execution patterns of known
malware programs. In this work, we propose a new class of detectors -
anomaly-based hardware malware detectors - that do not require signatures for
malware detection, and thus can catch a wider range of malware including
potentially novel ones. We use unsupervised machine learning to build profiles
of normal program execution based on data from performance counters, and use
these profiles to detect significant deviations in program behavior that occur
as a result of malware exploitation. We show that real-world exploitation of
popular programs such as IE and Adobe PDF Reader on a Windows/x86 platform can
be detected with nearly perfect certainty. We also examine the limits and
challenges in implementing this approach in face of a sophisticated adversary
attempting to evade anomaly-based detection. The proposed detector is
complementary to previously proposed signature-based detectors and can be used
together to improve security.Comment: 1 page, Latex; added description for feature selection in Section 4,
results unchange
Flow detectors having mechanical oscillators, and use thereof in flow characterization systems
An improved system (100), resonator flow detector (102) and method for characterizing a fluid sample that includes o injecting a fluid sample into a mobile phase of a flow characterization system (106), and detecting a property of the fluid sample > or of a component thereof with a flow detector (102) comprising a mechanical resonator (120), preferably one that is operated at a frequency less than about 1 MHz, such as tuning fork resonator
- …