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Logics for Contravariant Simulations [chapter]

Ignacio Fábregas, David de Frutos Escrig, Miguel Palomino
2010 Lecture Notes in Computer Science  
Now we show that their behaviors have also simple and natural logical characterizations, though more elaborated than those for the plain simulation semantics.  ...  Covariant-contravariant simulation and conformance simulation are two generalizations of the simple notion of simulation which aim at capturing the fact that it is not always the case that "the larger  ...  Logical Characterizations of the New Semantics Covariant-Contravariant Simulations The class L S characterizing the simulation semantics is defined in [3] as that containing tt, conjunctions i∈I ϕ  ... 
doi:10.1007/978-3-642-13464-7_18 fatcat:4vdzdborivf5znirmhl5i6o3py

Relating Modal Refinements, Covariant-Contravariant Simulations and Partial Bisimulations [chapter]

Luca Aceto, Ignacio Fábregas, David de Frutos Escrig, Anna Ingólfsdóttir, Miguel Palomino
2012 Lecture Notes in Computer Science  
This paper studies the relationships between three notions of behavioural preorder that have been proposed in the literature: refinement over modal transition systems, and the covariant-contravariant simulation  ...  The translations are also shown to preserve the modal properties that can be expressed in the logics that characterize those preorders.  ...  bisimulation set B, one can use the simpler, negation-free logic for the covariant-contravariant simulation preorder.  ... 
doi:10.1007/978-3-642-29320-7_18 fatcat:mttjpfiujnaqpnyoxfccwr4tfu

On the specification of modal systems: A comparison of three frameworks

Luca Aceto, Ignacio Fábregas, David de Frutos-Escrig, Anna Ingólfsdóttir, Miguel Palomino
2013 Science of Computer Programming  
This paper studies the relationships between three notions of behavioural preorder that have been proposed in the literature: refinement over modal transition systems, and the covariant-contravariant simulation  ...  The translations are also shown to preserve the modal properties that can be expressed in the logics that characterize those preorders.  ...  bisimulation set B, one can use the simpler, negation-free logic for the covariant-contravariant simulation preorder.  ... 
doi:10.1016/j.scico.2013.02.004 fatcat:tfpjtrqcxvcrrifqg4ypm3vlqu

Graphical representation of covariant-contravariant modal formulae

Luca Aceto, Ignacio Fábregas, David de Frutos-Escrig, Anna Ingólfsdóttir, Miguel Palomino
2011 Electronic Proceedings in Theoretical Computer Science  
Covariant-contravariant simulation is a combination of standard (covariant) simulation, its contravariant counterpart and bisimulation.  ...  We show in this paper that the formulae from the covariant-contravariant modal logic that admit a "graphical" representation by means of processes, modulo the covariant-contravariant simulation preorder  ...  Acknowledgement The authors would like to thank the anonymous referees for their comments and suggestions. Reflection and Preservation of Properties in Coalgebraic (bi)Simulations  ... 
doi:10.4204/eptcs.64.1 fatcat:tughygyofjappe325d3jtfpibq

Equational Characterization of Covariant-Contravariant Simulation and Conformance Simulation Semantics

Ignacio Fábregas, David de Frutos Escrig, Miguel Palomino
2010 Electronic Proceedings in Theoretical Computer Science  
Covariant-contravariant simulation and conformance simulation generalize plain simulation and try to capture the fact that it is not always the case that "the larger the number of behaviors, the better  ...  We have previously studied their logical characterizations and in this paper we present the axiomatizations of the preorders defined by the new simulation relations and their induced equivalences.  ...  In [12] we have also briefly presented the logical characterizations of the two semantics.  ... 
doi:10.4204/eptcs.32.1 fatcat:vn4pa4cjqnb2tbevzp4vsyfjqq

An arbitrary curvilinear-coordinate method for particle-in-cell modeling

C A Fichtl, J M Finn, K L Cartwright
2012 Computational Science & Discovery  
A generalized, curvilinear coordinate formulation of Poisson's equations to solve for the electrostatic fields on the uniform logical grid is also developed.  ...  A new approach to the kinetic simulation of plasmas in complex geometries, based on the Particle-in- Cell (PIC) simulation method, is explored.  ...  Acknowledgments The authors thank L Chacon, V Roytershteyn and G L Delzanno for many helpful discussions. The work of  ... 
doi:10.1088/1749-4699/5/1/014011 fatcat:6ts25xt2z5e7bdlkfefp7feoxm

Category Theoretic Models of Data Refinement

Michael Johnson, David Naumann, John Power
2009 Electronical Notes in Theoretical Computer Science  
The first is given by adjoint simulations; the second is given by the notion of lax logical relation.  ...  a first order imperative language, then study two main alternatives for extending that category theoretic analysis in order to account for higher order languages.  ...  extensions exist for total simulations even when the language includes contravariant constructs.  ... 
doi:10.1016/j.entcs.2008.12.064 fatcat:qb5nt34mwrdf3ceyywi2njt6ve

A SEGREGATED SOLUTION ALGORITHM FOR INCOMPRESSIBLE FLOWS IN GENERAL CO-ORDINATES

TONY W. H. SHEU, SHI-MIN LEE
1996 International Journal for Numerical Methods in Fluids  
A semi-implicit segregated solution algorithm felicitous for a large-scale flow simulation was utilized to solve the entire set of basic equations iteratively.  ...  Now that smoothness of the pnssure field is attainable, the remaining task is to ensure a disuete divergence-fire velocity field for an incompmsible flow simulation.  ...  As a consequence, any flow simulation involving contravariant velocity components is under the influence of grid uniformity and skewness.  ... 
doi:10.1002/(sici)1097-0363(19960330)22:6<515::aid-fld356>3.0.co;2-n fatcat:pv4m4mupcbehpkrw42ngzwcmsy

Refinement Modal Logic Based on Finite Approximation of Covariant-Contravariant Refinement

Huili Xing
2019 IEEE Access  
INDEX TERMS Approximation, axiom system, covariant-contravariant n-refinement, modal logic.  ...  for nCCRML, and explores some important properties of this axiom system: soundness, completeness, and decidability.  ...  ACKNOWLEDGMENTS The authors would like to thank the anonymous referees for their valuable suggestions, which have helped them to improve the presentation of the paper.  ... 
doi:10.1109/access.2019.2895078 fatcat:7ququeewk5c4nbhv2worteovzu

A curvilinear, fully implicit, conservative electromagnetic PIC algorithm in multiple dimensions

L. Chacón, G. Chen
2016 Journal of Computational Physics  
We extend a recently proposed fully implicit PIC algorithm for the Vlasov-Darwin model in multiple dimensions [Chen and Chacón, Comput. Phys.  ...  allows efficient use of large cell sizes, which are determined by accuracy considerations, not stability, and can be orders of magnitude larger than required in a standard explicit electromagnetic PIC simulation  ...  for a generic vector S, contravariant components are defined as S α = S · α and covariant components as S α = S · ∂x ∂ξ α .  ... 
doi:10.1016/j.jcp.2016.03.070 fatcat:d325drbgkreevlryamm5hwsaxa

A conservative implicit-PIC scheme for the hybrid kinetic-ion fluid-electron plasma model on curvilinear meshes [article]

A. Stanier, L. Chacon
2021 arXiv   pre-print
application, and a helical m=1 mode simulation for magnetic fusion energy application.  ...  Here, a novel conservative scheme for this model employing implicit particle-in-cell techniques is extended to arbitrary coordinate systems via curvilinear maps from logical to physical space.  ...  The mesh used for the simulation is shown in Fig. 8 .  ... 
arXiv:2110.03886v1 fatcat:s625t6nr6vdsdf3mwdsxcxln3a

Diagram techniques for multiple view geometry

Alberto Ruiz, Pedro E Lopez-de-Teruel
2009 2009 IEEE 12th International Conference on Computer Vision  
Multilinear algebra is a powerful theoretical tool for visual geometry, but widespread usage of traditional typographical notation often hides its conceptual elegance and simplicity.  ...  illustrated in several constructions, including straightforward derivations of the standard multiview relations (Fundamental Matrix, Trifocal and Quadrifocal Tensors), and nearly mechanical procedures for  ...  We thank the anonymous reviewers for their helpful comments.  ... 
doi:10.1109/iccv.2009.5459414 dblp:conf/iccv/RuizL09 fatcat:375vqvwgmjam3nxfrtbn4pecgq

Proofs of life: molecular-biology reasoning simulates cell behaviors from first principles [article]

René Vestergaard, Emmanuel Pietriga
2019 arXiv   pre-print
Constructivity and execution guarantee simulation when working over domain-specific languages.  ...  A main implication of our construction is that formal correctness provides a complementary perspective on science that is as fundamental there as for pure mathematics.  ...  , and Mun'de Vestergaard for discussions.  ... 
arXiv:1811.02478v3 fatcat:ohh5o3fvg5f4haxq2ril7tf4pa

General geometry PIC for MIMD computers

J.W. Eastwood, R.W. Hockney, W. Arter
1993 International Conference on Plasma Sciences (ICOPS)  
There, both the contravariant and covariant basis vectors are sketched for node I of the element.  ...  Although the software is suitable for parallel benchmarking. much work remains before it becomes a usable tool for microwave device simulation; the initialisation is difficult to use in 0 its present form  ... 
doi:10.1109/plasma.1993.593470 fatcat:qgme2wm5svddheuctxgfjo3rvq

Testing Semantics: Connecting Processes and Process Logics [chapter]

Dusko Pavlovic, Michael Mislove, James B. Worrell
2006 Lecture Notes in Computer Science  
This approach is based on generalizing from duality theories that now are common in semantics to logical connections, which are simply contravariant adjunctions.  ...  Our basic philosophy is that tests can be used as a basis for modeling interactions, as well as processes and the data on which they operate.  ...  Logical connections A logical connection is a contravariant adjunction M op ⊣ P : S op / / T between a category of "spaces" and a category of "types" or "theories".  ... 
doi:10.1007/11784180_24 fatcat:ba75kgvhsncpvdp6bcu7zijp74
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