2,030 research outputs found
Whole Genome Amplification (WGA) for archiving and genotyping of clinical isolates of Cryptosporidium species
Gotcha! I Know What You are Doing on the FPGA Cloud: Fingerprinting Co-Located Cloud FPGA Accelerators via Measuring Communication Links
In recent decades, due to the emerging requirements of computation
acceleration, cloud FPGAs have become popular in public clouds. Major cloud
service providers, e.g. AWS and Microsoft Azure have provided FPGA computing
resources in their infrastructure and have enabled users to design and deploy
their own accelerators on these FPGAs. Multi-tenancy FPGAs, where multiple
users can share the same FPGA fabric with certain types of isolation to improve
resource efficiency, have already been proved feasible. However, this also
raises security concerns. Various types of side-channel attacks targeting
multi-tenancy FPGAs have been proposed and validated. The awareness of security
vulnerabilities in the cloud has motivated cloud providers to take action to
enhance the security of their cloud environments.
In FPGA security research papers, researchers always perform attacks under
the assumption that attackers successfully co-locate with victims and are aware
of the existence of victims on the same FPGA board. However, the way to reach
this point, i.e., how attackers secretly obtain information regarding
accelerators on the same fabric, is constantly ignored despite the fact that it
is non-trivial and important for attackers. In this paper, we present a novel
fingerprinting attack to gain the types of co-located FPGA accelerators. We
utilize a seemingly non-malicious benchmark accelerator to sniff the
communication link and collect performance traces of the FPGA-host
communication link. By analyzing these traces, we are able to achieve high
classification accuracy for fingerprinting co-located accelerators, which
proves that attackers can use our method to perform cloud FPGA accelerator
fingerprinting with a high success rate. As far as we know, this is the first
paper targeting multi-tenant FPGA accelerator fingerprinting with the
communication side-channel.Comment: To be published in ACM CCS 202
Prison-Based Dog Training Programs: Standard Protocol
Across the United States, the number of prison-based dog training programs (PDPs) has increased substantially over the past several years. Currently, there are approximately 255 PDPs across 47 states that operate in a variety of correctional settings; however, there is little information available on how to successfully develop and implement a PDP. As a result, the research team from the Institute for Human-Animal Connection (IHAC) has developed a standard protocol to help guide PDP development and implementation.
This report identifies common practices of PDPs and incorporates both general and context-specific recommendations that were gathered from interviews with PDP staff, relevant literature, and content experts. In total, 21 interviews with 20 programs were conducted. PDPs were asked about several program features, including policies and procedures, key personnel, funding, materials, physical spaces, supervision and monitoring, safety considerations, animal welfare, handler selection and training, and program benefits.
This report highlights the benefits of PDPs to dogs, humans, prisons, local communities, and society as a whole and identifies challenges related to funding, staffing, and operating in a correctional setting. Findings from the protocol point to the importance of planning, staffing, communication, internal support, and training curriculum in successful program implementation
Neutrino-Induced Giant Air Showers in Large Extra Dimension Models
In models based on large extra dimensions where massive spin 2 exchange can
dominate at high energies, the neutrino-proton cross section can rise to
typical hadronic values at energies above 10^20 eV. The neutrino then becomes a
candidate for the primary that initiates the highest energy cosmic ray showers.
We investigate characteristics of neutrino-induced showers compared to
proton-induced showers. The comparison includes study of starting depth,
profile with depth, lateral particle distribution at ground and muon lateral
distribution at ground level. We find that for cross sections above 20 mb there
are regions of parameter space where the two types of showers are essentially
indistinguishable. We conclude that the neutrino candidate hypothesis cannot be
ruled out on the basis of shower characteristics.Comment: 24 pages, latex, 19 figures; text discussion and references added,
typos corrected; figures and conclusions unchange
Mining and analysis of audiology data to find significant factors associated with tinnitus masker
Objectives: The objective of this research is to find the factors associated with tinnitus masker from the literature, and by using the large amount of audiology data available from a large NHS (National Health Services, UK) hearing aid clinic. The factors evaluated were hearing impairment, age, gender, hearing aid type, mould and clinical comments.
Design: The research includes literature survey for factors associated with tinnitus masker, and performs the analysis of audiology data using statistical and data mining techniques.
Setting: This research uses a large audiology data but it also faced the problem of limited data for tinnitus.
Participants: It uses 1,316 records for tinnitus and other diagnoses, and 10,437 records of clinical comments from a hearing aid clinic.
Primary and secondary outcome measures: The research is looking for variables associated with tinnitus masker, and in future, these variables can be combined into a single model to develop a decision support system to predict about tinnitus masker for a patient.
Results: The results demonstrated that tinnitus maskers are more likely to be fit to individuals with milder forms of hearing loss, and the factors age, gender, type of hearing aid and mould were all found significantly associated with tinnitus masker. In particular, those patients having Age<=55 years were more likely to wear a tinnitus masker, as well as those with milder forms of hearing loss. ITE (in the ear) hearing aids were also found associated with tinnitus masker. A feedback on the results of association of mould with tinnitus masker from a professional audiologist of a large NHS (National Health Services, UK) was also taken to better understand them. The results were obtained with different accuracy for different techniques. For example, the chi-squared test results were obtained with 95% accuracy, for Support and Confidence only those results were retained which had more than 1% Support and 80% Confidence.
Conclusions: The variables audiograms, age, gender, hearing aid type and mould were found associated with the
choice of tinnitus masker in the literature and by using statistical and data mining techniques. The further work in this research would lead to the development of a decision support system for tinnitus masker with an explanation that how that decision was obtained
Saturation of electrical resistivity
Resistivity saturation is observed in many metallic systems with a large
resistivity, i.e., when the resistivity has reached a critical value, its
further increase with temperature is substantially reduced. This typically
happens when the apparent mean free path is comparable to the interatomic
separations - the Ioffe-Regel condition. Recently, several exceptions to this
rule have been found. Here, we review experimental results and early theories
of resistivity saturation. We then describe more recent theoretical work,
addressing cases both where the Ioffe-Regel condition is satisfied and where it
is violated. In particular we show how the (semiclassical) Ioffe-Regel
condition can be derived quantum-mechanically under certain assumptions about
the system and why these assumptions are violated for high-Tc cuprates and
alkali-doped fullerides.Comment: 16 pages, RevTeX, 15 eps figures, additional material available at
http://www.mpi-stuttgart.mpg.de/andersen/saturation
New insight into tuning magnetic phases of RMn6Sn6 kagome metals
Kagome metals with magnetic order offer the possibility of tuning topological
electronic states via external control parameters such as temperature or
magnetic field. ErMnSn (Er) is a member of a group of ,
~rare earth, compounds hosting ferromagnetic Mn kagome nets whose magnetic
moment direction and layer-to-layer magnetic correlations are strongly
influenced by coupling to magnetic moments in neighboring triangular
layers. Here, we use neutron diffraction and magnetization data to examine the
temperature-driven transition in Er from a planar-ferrimagnetic to
distorted-triple-spiral magnetic order. These data inform mean-field
calculations which highlight the fragile, tunable nature of the magnetism
caused by competing Mn-Mn and Mn-Er interlayer magnetic exchange couplings and
Mn and Er magnetic anisotropies. This competition results in the near
degeneracy of a variety of collinear, non-collinear, and non-coplanar magnetic
phases which we show are readily selected and adjusted via changing temperature
or magnetic field. Thermal fluctuations of the Er moment direction provide the
key to this tunability.Comment: 10 pages, 7 figures, Supplementary Informatio
Detecting Microscopic Black Holes with Neutrino Telescopes
If spacetime has more than four dimensions, ultra-high energy cosmic rays may
create microscopic black holes. Black holes created by cosmic neutrinos in the
Earth will evaporate, and the resulting hadronic showers, muons, and taus may
be detected in neutrino telescopes below the Earth's surface. We simulate such
events in detail and consider black hole cross sections with and without an
exponential suppression factor. We find observable rates in both cases: for
conservative cosmogenic neutrino fluxes, several black hole events per year are
observable at the IceCube detector; for fluxes at the Waxman-Bahcall bound,
tens of events per year are possible. We also present zenith angle and energy
distributions for all three channels. The ability of neutrino telescopes to
differentiate hadrons, muons, and possibly taus, and to measure these
distributions provides a unique opportunity to identify black holes, to
experimentally constrain the form of black hole production cross sections, and
to study Hawking evaporation.Comment: 20 pages, 9 figure
Orbital character of the spin-reorientation transition in TbMnSn
Ferromagnetic (FM) order in a two-dimensional kagome layer is predicted to
generate a topological Chern insulator without an applied magnetic field. The
Chern gap is largest when spin moments point perpendicular to the kagome layer,
enabling the capability to switch topological transport properties, such as the
quantum anomalous Hall effect, by controlling the spin orientation. In
TbMnSn, the uniaxial magnetic anisotropy of the Tb ion is
effective at generating the Chern state within the FM Mn kagome layers while a
spin-reorientation (SR) transition to easy-plane order above K
provides a mechanism for switching. Here, we use inelastic neutron scattering
to provide key insights into the fundamental nature of the SR transition. The
observation of two Tb excitations, which are split by the magnetic anisotropy
energy, indicates an effective two-state orbital character for the Tb ion, with
a uniaxial ground state and an isotropic excited state. The simultaneous
observation of both modes below confirms that orbital fluctuations are
slow on magnetic and electronic time scales ps and act as a
spatially-random orbital alloy. A thermally-driven critical concentration of
isotropic Tb ions triggers the SR transition.Comment: 21 page
Extensive air showers with TeV-scale quantum gravity
One of the possible consequences of the existence of extra degrees of freedom
beyond the electroweak scale is the increase of neutrino-nucleon cross sections
() beyond Standard Model predictions. At ultra-high energies
this may allow the existence of neutrino-initiated extensive air showers. In
this paper, we examine the most relevant observables of such showers. Our
analysis indicates that the future Pierre Auger Observatory could be
potentially powerful in probing models with large compact dimensions.Comment: 7 pages revtex, 5 eps fig
- …