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Dynamic gain scheduled control of a Hawk scale model

T. Richardson, M. Lowenberg, C. Jones, A. Dubs
2007 Aeronautical Journal  
In practice, the controller gains are often scheduled against relatively slowly-varying system states such as altitude or velocity.  ...  In this paper, the novel design process, using eigenstructure assignment, is applied to a mathematical second-order longitudinal aircraft model which represents an approximate BAe Hawk wind-tunnel model  ...  is varied.  ... 
doi:10.1017/s0001924000004723 fatcat:z7y6ab4s5zevzds2krngwovgnm

Analogue Hawking Radiation in Nonlinear LC Transmission Lines

Haruna Katayama, Noriyuki Hatakenaka, Ken-ichi Matsuda
2021 Universe  
Analogue systems are used to test Hawking radiation, which is hard to observe in actual black holes.  ...  In this work, we propose analogue Hawking radiation in a nonlinear LC transmission line including nonlinear capacitors with a third-order nonlinearity in voltage.  ...  fluid and (Hawking) phonons in sonic systems are reversed [10] .  ... 
doi:10.3390/universe7090334 fatcat:earld3rdbva4hig42stpmfet34

Optical black-hole analogues

Dentcho A. Genov
2011 Nature Photonics  
This process should be a common optical occurrence, as pointed by Belgiorno et al., and must be considered whenever spontaneous emission processes are studied in systems with varying group and phase velocities  ...  a new type of nonlinear optical process.  ... 
doi:10.1038/nphoton.2011.5 fatcat:jkmgdawsfbamfeksg4ci3hce6a

Quantum Dynamics of Nonlinear Cavity Systems [article]

Paul D. Nation
2010 arXiv   pre-print
This setup allows for quantum effects such as backreaction and analogue space-time fluctuations on the Hawking process.  ...  We investigate the quantum dynamics of three different configurations of nonlinear cavity systems.  ...  Creating a space-time varying current pulse, as in Ref. [93] , can also be accomplished in our device.  ... 
arXiv:1009.3075v1 fatcat:bvqe6jvgindafli7nbunxrjtfy

Experimental evidence of analogue Hawking radiation from ultrashort laser pulse filaments

E Rubino, F Belgiorno, S L Cacciatori, M Clerici, V Gorini, G Ortenzi, L Rizzi, V G Sala, M Kolesik, D Faccio
2011 New Journal of Physics  
In particular, recent progress in the field of transformation optics, i.e. the description of optical systems in terms of curved space-time geometries, has led to a detailed description of methods for  ...  Curved space-times and, in particular, event horizons of astrophysical black holes are expected to excite the quantum vacuum and give rise to an emission of quanta known as Hawking radiation.  ...  Acknowledgments We acknowledge P Di Trapani and A Couairon for technical assistance at the Virtual Institute of Nonlinear Optics (VINO) and the VINO numerical laboratory.  ... 
doi:10.1088/1367-2630/13/8/085005 fatcat:oosp7t43lrf2lh4ls3zjn5r5dq

Optical analogues of black-hole horizons [article]

Yuval Rosenberg
2020 arXiv   pre-print
Hawking radiation is unlikely to be measured from a real black-hole, but can be tested in laboratory analogues.  ...  A refractive index perturbation produce an optical analogue of the black-hole horizon and Hawking radiation that is made of light.  ...  The generation of NRR in media with quadratic nonlinearity was also related to a cascading process [102] , which must also be the case for cubic materials.  ... 
arXiv:2002.04216v2 fatcat:hvadurtvk5fdvgtmat2p4zamq4

Modeling The Intensity Function Of Point Process Via Recurrent Neural Networks [article]

Shuai Xiao, Junchi Yan, Stephen M. Chu, Xiaokang Yang, Hongyuan Zha
2017 arXiv   pre-print
Meanwhile end-to-end training opens the venue for reusing existing rich techniques in deep network for point process modeling.  ...  For utility, our method allows a black-box treatment for modeling the intensity which is often a pre-defined parametric form in point processes.  ...  In fact, Hawkes process uses a full explicit parametric model and RMTPP misses the dense time series features to model time-varying base intensity and assumes a partially parametric form for it.  ... 
arXiv:1705.08982v1 fatcat:fdzqe6urqnfzpbhlxbfpuxk32m

Modeling the Intensity Function of Point Process Via Recurrent Neural Networks

Shuai Xiao, Junchi Yan, Xiaokang Yang, Hongyuan Zha, Stephen Chu
2017 PROCEEDINGS OF THE THIRTIETH AAAI CONFERENCE ON ARTIFICIAL INTELLIGENCE AND THE TWENTY-EIGHTH INNOVATIVE APPLICATIONS OF ARTIFICIAL INTELLIGENCE CONFERENCE  
Meanwhile end-to-end training opens the venue for reusing existing rich techniques in deep network for point process modeling.  ...  For utility, our method allows a black-box treatment for modeling the intensity which is often a pre-defined parametric form in point processes.  ...  In fact, Hawkes process uses a full explicit parametric model and RMTPP misses the dense time series features to model time-varying base intensity and assumes a partially parametric form for it.  ... 
doi:10.1609/aaai.v31i1.10724 fatcat:f4h6w227szbzxj4qknylwtjrnq

Blackbody Emission from Light Interacting with an Effective Moving Dispersive Medium

M. Petev, N. Westerberg, D. Moss, E. Rubino, C. Rimoldi, S. L. Cacciatori, F. Belgiorno, D. Faccio
2013 Physical Review Letters  
Based on these results, diamond is proposed as a promising candidate medium for future studies of Hawking emission from artificial, dispersive horizons.  ...  Intense laser pulses excite a nonlinear polarisation response that may create an effective flowing medium and, under appropriate conditions, a blocking horizon for light.  ...  In Fig. 3(d) , we compare the (comoving) Hawking temperature (solid curve) and the numerically estimated temperatures (red dots) for n with a fixed v and varying n max .  ... 
doi:10.1103/physrevlett.111.043902 pmid:23931369 fatcat:xab4jtcbbvfotb2vqfysciis6i

On the stability and dynamics of stochastic spiking neuron models: Nonlinear Hawkes process and point process GLMs

Felipe Gerhard, Moritz Deger, Wilson Truccolo, Jeff Beck
2017 PLoS Computational Biology  
Stability and dynamics of nonlinear Hawkes processes and PP-GLMs PLOS Computational Biology |  ...  The nonlinear Hawkes process is a statistical model that captures these complex dependencies.  ...  The nonlinear Hawkes process The nonlinear Hawkes process is a flexible class of self-exciting and/or self-inhibiting point process models [9] .  ... 
doi:10.1371/journal.pcbi.1005390 pmid:28234899 pmcid:PMC5325182 fatcat:4cv7fh6xrvhshfkukrpcdh3jsa

Analogue Hawking Radiation in a dc-SQUID Array Transmission Line

P. D. Nation, M. P. Blencowe, A. J. Rimberg, E. Buks
2009 Physical Review Letters  
Being a fundamentally quantum mechanical device, this setup allows for investigations of quantum effects such as back-reaction and analogue space-time fluctuations on the Hawking process.  ...  Biasing the array with a space-time varying flux modifies the propagation velocity of the waveguide, leading to an effective metric with an horizon.  ...  Requiring the propagation speed to vary in both space and time, c 2 !  ... 
doi:10.1103/physrevlett.103.087004 pmid:19792751 fatcat:bp3zyh4cwbcafhqzyhw4jb2msu

High-dimensional Hawkes processes for limit order books: modelling, empirical analysis and numerical calibration

Xiaofei Lu, Frédéric Abergel
2018 Quantitative finance (Print)  
High-dimensional Hawkes processes with exponential kernels are used to describe limit order books in order-driven financial markets.  ...  The observation of inhibition effects is particularly interesting, and leads us to the use of non-linear Hawkes processes.  ...  Nonlinear Hawkes process model This subsection addresses the shortcomings of linear Hawkes models in reproducing some characteristics of forward recurrence times and signature plots.  ... 
doi:10.1080/14697688.2017.1403142 fatcat:aqheryz66nbelbvtzxhiugfgjq

Laser pulse analogues for gravity and analogue Hawking radiation

Daniele Faccio
2012 Contemporary physics (Print)  
, such as Hawking radiation, are predicted to occur also in the analogue systems.  ...  However there is a fundamental difference with respect to Hawking radiation: the thermal emission obtained by standard nonlinear optical parametric processes is thermal with a different temperature characterising  ... 
doi:10.1080/00107514.2011.642559 fatcat:4kcazppce5g7dnjz6dlj7zppp4

Ubiquitous power law scaling in nonlinear self-excited Hawkes processes [article]

Kiyoshi Kanazawa, Didier Sornette
2021 arXiv   pre-print
In parallel, self-excited dynamics is a prevalent characteristic of many systems, from the physics of shot noise and intermittent processes, to seismicity, financial and social systems.  ...  Solving the corresponding master equations, we find that a wide class of such nonlinear Hawkes processes have the PDF of their intensities described by a power law on the condition that (i) the intensity  ...  between stochasticity and nonlinear dynamics in many complex systems.  ... 
arXiv:2102.00242v2 fatcat:cwurorlftracxnwodrd3xc4eje

Analog Hawking radiation from an acoustic black hole in a flowing polariton superfluid

Dario Gerace, Iacopo Carusotto
2012 Physical Review B  
We theoretically study Hawking radiation processes from an analog acoustic black hole in a flowing superfluid of exciton-polaritons in a one-dimensional semiconductor microcavity.  ...  Experimentally observable signatures of the analog Hawking radiation are identified in the scattering of phonon wavepackets off the horizon, as well as in the spatial correlation pattern of quantum fluctuations  ...  DG warmly acknowledges the friendly hospitality of the INO-CNR BEC Center in Trento, where most of this work has been conceived and carried out, and L.C. Andreani for supporting this research.  ... 
doi:10.1103/physrevb.86.144505 fatcat:6j25boqj4zbovhhpz5ec57j6aq
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