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Formal Verification of a Programmable Hypersurface [chapter]

Panagiotis Kouvaros, Dimitrios Kouzapas, Anna Philippou, Julius Georgiou, Loukas Petrou, Andreas Pitsillides
2018 Lecture Notes in Computer Science  
This paper presents work in progress on the design and formal verification of a programmable metasurface, the Hypersurface, as part of the requirements of the VISORSURF research program (HORIZON 2020 FET-OPEN  ...  This paper shares the experience of a rigorous design procedure for the Hypersurface network, that involves iterations between designing a network and its protocols and the formal evaluation of each design  ...  The Hypersurface: Requirements and Design Parameters In this section we present the main requirements and design parameters of the Hypersurface, as imposed in the context of the VISORSURF programme and  ... 
doi:10.1007/978-3-030-00244-2_6 fatcat:rpihi2fcsfawho5527eg7numj4

Observational cosmology using characteristic numerical relativity: Characteristic formalism on null geodesics

P. J. van der Walt, N. T. Bishop
2012 Physical Review D  
The characteristic formalism of numerical relativity is based on a system of coordinates aligned with outgoing null cones.  ...  This is because after refocussing, the diameter distance ceases to be a unique measure of distance.  ...  A simple choice of bang function is implemented as a verification model: t B (r) = br, (43) with b being a constant.  ... 
doi:10.1103/physrevd.85.044016 fatcat:ahshokwamncvdeivkfehsglrki

Observational cosmology using characteristic numerical relativity

P. J. van der Walt, N. T. Bishop
2010 Physical Review D  
In a numerical experiment using the characteristic formalism, it is shown how the historical evolution of a LTB universe compares to that of the ΛCDM model given identical observational data on a local  ...  The characteristic formalism in numerical relativity, which has been developed to study gravitational waves, and the observer metric approach in observational cosmology both make use of coordinate systems  ...  Verification results A simple choice of bang function is implemented as a verification model: t B (r) = br, (33) with b being a constant.  ... 
doi:10.1103/physrevd.82.084001 fatcat:w5fgfsq5ajcoloyolytoaoxeyy

Computational Issues in Intelligent Control: Discrete-Event and Hybrid Systems [chapter]

XENOFON D. KOUTSOUKOS, PANOS J. ANTSAKLIS
2000 Soft Computing and Intelligent Systems  
The design, simulation, and verification of intelligent control systems is highly nontrivial and typically involves significant amount of computations.  ...  In particular, we discuss how the design, simulation, and verification of discrete-event and hybrid systems, which are central in intelligent control, requires the development of computationally efficient  ...  Nikos Chrisochoides of the Computer Science and Engineering Department at the University of Notre Dame for his valuable assistance concerning the parallel computing architecture.  ... 
doi:10.1016/b978-012646490-0/50006-8 fatcat:tpqu57oywrhwtfcrvohzhr3trq

Process modelling for hybrid control

G. Mušič, M. Šikovc, B. Zupančič
2002 Systems Analysis Modelling Simulation  
A discrete-event plant model is developed and a discrete controller is designed to prevent entering into a forbidden region of the state space.  ...  Paper deals with modelling methods for the purpose of control of hybrid systems, a class of dynamic systems where the behaviour of interest is determined by interacting time continuous and discrete-event  ...  Models can be analysed by well developed techniques, and control can be synthesised in a formal way.  ... 
doi:10.1080/716067185 fatcat:rgqkznlh5zf6pb22cuz2ptsmha

Obtaining time-dependent multi-dimensional dividing surfaces using Lagrangian descriptors

Matthias Feldmaier, Andrej Junginger, Jörg Main, Günter Wunner, Rigoberto Hernandez
2017 Chemical Physics Letters  
We extend the formalism---constructed using Lagrangian Descriptors---to systems with additional bath degrees of freedom.  ...  The propagation of reactant ensembles provides a numerical demonstration that our dividing surface is recrossing-free and leads to exact TST rates.  ...  Acknowledgments AJ acknowledges the Alexander von Humboldt Foundation, Germany, for support through a Feodor Lynen Fellowship.  ... 
doi:10.1016/j.cplett.2017.09.008 fatcat:7ipgmpwfjncctlh4kab3bxvyy4

Analysis of the state of prestressed structure using data collection simulation technique

Szczepan Woliński, Tomasz Pytlowany, K. Wilde, M. Niedostatkiewicz
2019 MATEC Web of Conferences  
Desing basis, procedures and results of the DOE technique use were presented on the example of a post-tensioned beam designed in accordance with the requirements of Eurocode 2.  ...  The paper presents a method of analysing the impact of basic variables on parameters characterizing the state of prestressed structures in transient and persistent design situation based on computer simulations  ...  In order to use a multi-dimensional hypersurface of the response surface to the practical sensitivity analysis, i.e. the choice of design solution close to optimum or for verification of a particular solution  ... 
doi:10.1051/matecconf/201926208006 fatcat:3pxkqvazpjemdnu24qbnk5dgue

Conformal Infinity

Jörg Frauendiener
2004 Living Reviews in Relativity  
The notion of conformal infinity has a long history within the research in Einstein's theory of gravity.  ...  Finally, it is shown that the conformal field equations provide a very powerful method within numerical relativity to study global problems such as gravitational wave propagation and detection.  ...  conserved quantities; • multipole moments; • asymptotic quantization procedures; • H-spaces and the twistor programme; • the null hypersurface formulation of general relativity; • the conformal field equations  ... 
doi:10.12942/lrr-2004-1 pmid:28179863 pmcid:PMC5256109 fatcat:edevz7b5j5dlrps64ida5rlc7m

Conformal Infinity

Jörg Frauendiener
2000 Living Reviews in Relativity  
The notion of conformal infinity has a long history within the research in Einstein's theory of gravity.  ...  Finally, it is shown that the conformal field equations provide a very powerful method within numerical relativity to study global problems such as gravitational wave propagation and detection.  ...  quantities; multipole moments; asymptotic quantization procedures; H-spaces and the twistor programme; the null hypersurface formulation of general relativity; the conformal field equations and their  ... 
doi:10.12942/lrr-2000-4 pmid:28163630 pmcid:PMC5253926 fatcat:vymcmlisvvcwlai6gfqeclppny

Integrability of dispersionless Hirota type equations in 4D and the symplectic Monge-Ampere property [article]

E.V. Ferapontov, B. Kruglikov, V. Novikov
2018 arXiv   pre-print
In 4D this yields a complete classification of integrable dispersionless PDEs of Hirota type through a list of heavenly type equations arising in self-dual gravity.  ...  We also give a criterion of linerisability of a Hirota type equation via flatness of the corresponding conformal structure, and study symmetry properties of integrable equations.  ...  The programmes are available from the arXiv version of this paper.  ... 
arXiv:1707.08070v2 fatcat:ewy3vn5binehrms5eoo6ridnui

Polynomial duality-symmetric lagrangians for free p-forms

Sukruti Bansal, Oleg Evnin, Karapet Mkrtchyan
2021 European Physical Journal C: Particles and Fields  
equations of motion that shows a great economy and simplicity of this formalism.  ...  AbstractWe explore the properties of polynomial Lagrangians for chiral p-forms previously proposed by the last named author, and in particular, provide a self-contained treatment of the symmetries and  ...  Research of S.B. and O.E. is supported by the CUniverse research promotion initiative (CUAASC) at Chulalongkorn University.  ... 
doi:10.1140/epjc/s10052-021-09049-0 fatcat:thavbtuop5gcbgrmity5om6zuy

Killing spinor data on distorted black hole horizons and the uniqueness of stationary vacuum black holes

M J Cole, I Rácz, J A Valiente Kroon
2018 Classical and quantum gravity  
Once the existence of a Hermitian Killing vector is guaranteed, one can use a characterisation of the Kerr spacetime due to Mars to identify the particular subfamily of 2-metrics giving rise to a member  ...  In particular, we provide conditions on the bifurcation sphere ensuring the existence of a Killing spinor.  ...  JAVK thanks the hospitality of the Wigner Institute in the course of a visit related to this work.  ... 
doi:10.1088/1361-6382/aade6e fatcat:qhvue3c4xzbazgcyq2cjnm4itm

Noncommutative Geometry, Hodge Theorem and Holography [article]

I. P. Zois
2009 arXiv   pre-print
Some time ago we presented an article (which was in fact the outline of a research programme) in which we argued for the need to develop a nonommutative version of topological quantum field theories (NCTQFT  ...  Hogan et all, has demonstrated the possibility to get experimental verification of holography; if this comes true, then that would indicate that quantum gravity is indeed a TQFT.  ...  The NC version of this should be obtained in a straightforward way for the case of a, say, noncommutative 3-sphere and using the NC Laplacian.  ... 
arXiv:0912.2449v1 fatcat:5hboadvkfzemxi4aafes2bxtdq

The Experiment Paradox in Physics

Michał Eckstein, Paweł Horodecki
2020 Foundations of Science  
We argue that the unravelled paradox induces a new type of 'ontic' underdetermination, which has deep consequences for the methodological foundations of physics.  ...  Modern physics is founded on two mainstays: mathematical modelling and empirical verification. These two assumptions are prerequisite for the objectivity of scientific discourse.  ...  The work of ME was supported by the National Science Centre in Poland under the research grant Sonatina (2017/24/C/ST2/00322).  ... 
doi:10.1007/s10699-020-09711-y fatcat:iul533wmwzg6xezsvuntsgnvg4

Conformal boundary operators, T-curvatures, and conformal fractional Laplacians of odd order [article]

A. Rod Gover, Lawrence J. Peterson
2018 arXiv   pre-print
Combined with the (conformal Laplacian power) GJMS operators, a suitable selection of the boundary operators yields formally self-adjoint elliptic conformal boundary problems.  ...  Working on a conformal manifold with boundary, we show that the operators yield odd-order conformally invariant fractional Laplacian pseudo-differential operators.  ...  In a similar way, a hypersurface invariant is actually a rule which defines an invariant in a neigbourhood of any hypersurface (Σ, c) of any (M, c).  ... 
arXiv:1802.08366v1 fatcat:wekyubcwunewpg2krwy2dii54e
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