1,121 research outputs found
An 826 MOPS, 210 uW/MHz Unum ALU in 65 nm
To overcome the limitations of conventional floating-point number formats, an
interval arithmetic and variable-width storage format called universal number
(unum) has been recently introduced. This paper presents the first (to the best
of our knowledge) silicon implementation measurements of an
application-specific integrated circuit (ASIC) for unum floating-point
arithmetic. The designed chip includes a 128-bit wide unum arithmetic unit to
execute additions and subtractions, while also supporting lossless (for
intermediate results) and lossy (for external data movements) compression units
to exploit the memory usage reduction potential of the unum format. Our chip,
fabricated in a 65 nm CMOS process, achieves a maximum clock frequency of 413
MHz at 1.2 V with an average measured power of 210 uW/MHz
N=2 Generalized Superconformal Quiver Gauge Theory
Four dimensional N=2 generalized superconformal field theory can be defined
by compactifying six dimensional (0,2) theory on a Riemann surface with regular
punctures. In previous studies, gauge coupling constant space is identified
with the moduli space of punctured Riemann surface M_{g,n}. We show that the
weakly coupled gauge group description corresponds to a stable nodal curve, and
the coupling space is actually the Deligne-Mumford compactification
\bar{M}_{g,n}. We also give an algorithm to determine the weakly coupled gauge
group and matter content in any duality frame.Comment: v2, reorganizing the materials, discussions on 2d CFT is remove
Quantitative multi-objective verification for probabilistic systems
We present a verification framework for analysing multiple quantitative objectives of systems that exhibit both nondeterministic and stochastic behaviour. These systems are modelled as probabilistic automata, enriched with cost or reward structures that capture, for example, energy usage or performance metrics. Quantitative properties of these models are expressed in a specification language that incorporates probabilistic safety and liveness properties, expected total cost or reward, and supports multiple objectives of these types. We propose and implement an efficient verification framework for such properties and then present two distinct applications of it: firstly, controller synthesis subject to multiple quantitative objectives; and, secondly, quantitative compositional verification. The practical applicability of both approaches is illustrated with experimental results from several large case studies
More Three Dimensional Mirror Pairs
We found a lot of new three dimensional N = 4 mirror pairs generalizing
previous considerations on three dimensional generalized quiver gauge theories.
We recovered almost all previous discovered mirror pairs with these
constructions. One side of these mirror pairs are always the conventional
quiver gauge theories. One of our result can also be used to determine the
matter content and weakly coupled gauge groups of four dimensional N = 2
generalized quiver gauge theories derived from six dimensional A_N and D_N
theory, therefore we explicitly constructed four dimensional S-duality pairs.Comment: 33 pages, 18 figures version2 minor correction
A note on fermions in holographic QCD
We study the fermionic sector of a probe D8-brane in the supergravity
background made of D4-branes compactified on a circle with supersymmetry broken
explicitly by the boundary conditions. At low energies the dual field theory is
effectively four-dimensional and has proved surprisingly successful in
recovering qualitative and quantitative properties of QCD. We investigate
fluctuations of the fermionic fields on the probe D8-brane and interpret these
as mesinos (fermionic superpartners of mesons). We demonstrate that the masses
of these modes are comparable to meson masses and show that their interactions
with ordinary mesons are not suppressed.Comment: 21+1 pp, 1 figure; v2: typos corrected, refs. adde
Nilpotent orbits and codimension-two defects of 6d N=(2,0) theories
We study the local properties of a class of codimension-2 defects of the 6d
N=(2,0) theories of type J=A,D,E labeled by nilpotent orbits of a Lie algebra
\mathfrak{g}, where \mathfrak{g} is determined by J and the outer-automorphism
twist around the defect. This class is a natural generalisation of the defects
of the 6d theory of type SU(N) labeled by a Young diagram with N boxes. For any
of these defects, we determine its contribution to the dimension of the Higgs
branch, to the Coulomb branch operators and their scaling dimensions, to the 4d
central charges a and c, and to the flavour central charge k.Comment: 57 pages, LaTeX2
Laelaps: An Energy-Efficient Seizure Detection Algorithm from Long-term Human iEEG Recordings without False Alarms
We propose Laelaps, an energy-efficient and fast learning algorithm with no false alarms for epileptic seizure detection from long-term intracranial electroencephalography (iEEG) signals. Laelaps uses end-to-end binary operations by exploiting symbolic dynamics and brain-inspired hyperdimensional computing. Laelaps's results surpass those yielded by state-of-the-art (SoA) methods [1], [2], [3], including deep learning, on a new very large dataset containing 116 seizures of 18 drug-resistant epilepsy patients in 2656 hours of recordings - each patient implanted with 24 to 128 iEEG electrodes. Laelaps trains 18 patient-specific models by using only 24 seizures: 12 models are trained with one seizure per patient, the others with two seizures. The trained models detect 79 out of 92 unseen seizures without any false alarms across all the patients as a big step forward in practical seizure detection. Importantly, a simple implementation of Laelaps on the Nvidia Tegra X2 embedded device achieves 1.7
7-3.9
7 faster execution and 1.4
7-2.9
7 lower energy consumption compared to the best result from the SoA methods. Our source code and anonymized iEEG dataset are freely available at http://ieeg-swez.ethz.ch
Optimal space of linear classical observables for Maxwell k-forms via spacelike and timelike compact de Rham cohomologies
Being motivated by open questions in gauge field theories, we consider non-standard de Rham cohomology groups for timelike compact and spacelike compact support systems. These cohomology groups are shown to be isomorphic respectively to the usual de Rham cohomology of a spacelike Cauchy surface and its counterpart with compact support. Furthermore, an analog of the usual Poincar\ue9 duality for de Rham cohomology is shown to hold for the case with non-standard supports as well. We apply these results to find optimal spaces of linear observables for analogs of arbitrary degree k of both the vector potential and the Faraday tensor. The term optimal has to be intended in the following sense: The spaces of linear observables we consider distinguish between different configurations; in addition to that, there are no redundant observables. This last point in particular heavily relies on the analog of Poincar\ue9 duality for the new cohomology groups
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