53,505 research outputs found
On Formal Methods for Collective Adaptive System Engineering. {Scalable Approximated, Spatial} Analysis Techniques. Extended Abstract
In this extended abstract a view on the role of Formal Methods in System
Engineering is briefly presented. Then two examples of useful analysis
techniques based on solid mathematical theories are discussed as well as the
software tools which have been built for supporting such techniques. The first
technique is Scalable Approximated Population DTMC Model-checking. The second
one is Spatial Model-checking for Closure Spaces. Both techniques have been
developed in the context of the EU funded project QUANTICOL.Comment: In Proceedings FORECAST 2016, arXiv:1607.0200
Living IoT: A Flying Wireless Platform on Live Insects
Sensor networks with devices capable of moving could enable applications
ranging from precision irrigation to environmental sensing. Using mechanical
drones to move sensors, however, severely limits operation time since flight
time is limited by the energy density of current battery technology. We explore
an alternative, biology-based solution: integrate sensing, computing and
communication functionalities onto live flying insects to create a mobile IoT
platform.
Such an approach takes advantage of these tiny, highly efficient biological
insects which are ubiquitous in many outdoor ecosystems, to essentially provide
mobility for free. Doing so however requires addressing key technical
challenges of power, size, weight and self-localization in order for the
insects to perform location-dependent sensing operations as they carry our IoT
payload through the environment. We develop and deploy our platform on
bumblebees which includes backscatter communication, low-power
self-localization hardware, sensors, and a power source. We show that our
platform is capable of sensing, backscattering data at 1 kbps when the insects
are back at the hive, and localizing itself up to distances of 80 m from the
access points, all within a total weight budget of 102 mg.Comment: Co-primary authors: Vikram Iyer, Rajalakshmi Nandakumar, Anran Wang,
In Proceedings of Mobicom. ACM, New York, NY, USA, 15 pages, 201
Focused Proofreading: Efficiently Extracting Connectomes from Segmented EM Images
Identifying complex neural circuitry from electron microscopic (EM) images
may help unlock the mysteries of the brain. However, identifying this circuitry
requires time-consuming, manual tracing (proofreading) due to the size and
intricacy of these image datasets, thus limiting state-of-the-art analysis to
very small brain regions. Potential avenues to improve scalability include
automatic image segmentation and crowd sourcing, but current efforts have had
limited success. In this paper, we propose a new strategy, focused
proofreading, that works with automatic segmentation and aims to limit
proofreading to the regions of a dataset that are most impactful to the
resulting circuit. We then introduce a novel workflow, which exploits
biological information such as synapses, and apply it to a large dataset in the
fly optic lobe. With our techniques, we achieve significant tracing speedups of
3-5x without sacrificing the quality of the resulting circuit. Furthermore, our
methodology makes the task of proofreading much more accessible and hence
potentially enhances the effectiveness of crowd sourcing
The Infocus Hard X-ray Telescope: Pixellated CZT Detector/Shield Performance and Flight Results
The CZT detector on the Infocus hard X-ray telescope is a pixellated
solid-state device capable of imaging spectroscopy by measuring the position
and energy of each incoming photon. The detector sits at the focal point of an
8m focal length multilayered grazing incidence X-ray mirror which has
significant effective area between 20--40 keV. The detector has an energy
resolution of 4.0keV at 32keV, and the Infocus telescope has an angular
resolution of 2.2 arcminute and a field of view of about 10 arcminutes. Infocus
flew on a balloon mission in July 2001 and observed Cygnus X-1. We present
results from laboratory testing of the detector to measure the uniformity of
response across the detector, to determine the spectral resolution, and to
perform a simple noise decomposition. We also present a hard X-ray spectrum and
image of Cygnus X-1, and measurements of the hard X-ray CZT background obtained
with the SWIN detector on Infocus.Comment: To appear in the proceedings of the SPIE conference "Astronomical
Telescopes and Instrumentation", #4851-116, Kona, Hawaii, Aug. 22-28, 2002.
12 pages, 9 figure
Microprocessor fault-tolerance via on-the-fly partial reconfiguration
This paper presents a novel approach to exploit FPGA dynamic partial reconfiguration to improve the fault tolerance of complex microprocessor-based systems, with no need to statically reserve area to host redundant components. The proposed method not only improves the survivability of the system by allowing the online replacement of defective key parts of the processor, but also provides performance graceful degradation by executing in software the tasks that were executed in hardware before a fault and the subsequent reconfiguration happened. The advantage of the proposed approach is that thanks to a hardware hypervisor, the CPU is totally unaware of the reconfiguration happening in real-time, and there's no dependency on the CPU to perform it. As proof of concept a design using this idea has been developed, using the LEON3 open-source processor, synthesized on a Virtex 4 FPG
Recommended from our members
ADAR-mediated RNA editing suppresses sleep by acting as a brake on glutamatergic synaptic plasticity.
It has been postulated that synaptic potentiation during waking is offset by a homoeostatic reduction in net synaptic strength during sleep. However, molecular mechanisms to support such a process are lacking. Here we demonstrate that deficiencies in the RNA-editing gene Adar increase sleep due to synaptic dysfunction in glutamatergic neurons in Drosophila. Specifically, the vesicular glutamate transporter is upregulated, leading to over-activation of NMDA receptors, and the reserve pool of glutamatergic synaptic vesicles is selectively expanded in Adar mutants. Collectively these changes lead to sustained neurotransmitter release under conditions that would otherwise result in synaptic depression. We propose that a shift in the balance from synaptic depression towards synaptic potentiation in sleep-promoting neurons underlies the increased sleep pressure of Adar-deficient animals. Our findings provide a plausible molecular mechanism linking sleep and synaptic plasticity
Relative resilience to noise of standard and sequential approaches to measurement-based quantum computation
A possible alternative to the standard model of measurement-based quantum
computation (MBQC) is offered by the sequential model of MBQC -- a particular
class of quantum computation via ancillae. Although these two models are
equivalent under ideal conditions, their relative resilience to noise in
practical conditions is not yet known. We analyze this relationship for various
noise models in the ancilla preparation and in the entangling-gate
implementation. The comparison of the two models is performed utilizing both
the gate infidelity and the diamond distance as figures of merit. Our results
show that in the majority of instances the sequential model outperforms the
standard one in regard to a universal set of operations for quantum
computation. Further investigation is made into the performance of sequential
MBQC in experimental scenarios, thus setting benchmarks for possible cavity-QED
implementations.Comment: 11 pages, 11 figures; close to published versio
- …