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Quantum random walk in a two-dimensional lattice with randomly distributed traps is investigated. Distributions of quantum walkers are evaluated dynamically for the cases of Hadamard, Fourier, and Grover coins, and quantum to classical…

Quantum Physics · Physics 2009-09-09 Meltem Gonulol , Ekrem Aydiner , Ozgur E. Mustecaplioglu

We study a symmetric random walk (RW) in one spatial dimension in environment, formed by several zones of finite width, where the probability of transition between two neighboring points and corresponding diffusion coefficient are…

Statistical Mechanics · Physics 2017-04-03 A. V. Nazarenko , V. Blavatska

We develop a method for separating quasars from other variable point sources using SDSS Stripe 82 light curve data for ~10,000 variable objects. To statistically describe quasar variability, we use a damped random walk model parametrized by…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-28 C. L. MacLeod , K. Brooks , Z. Ivezic , C. S. Kochanek , R. Gibson , A. Meisner , S. Kozlowski , B. Sesar , A. C. Becker , W. de Vries

Dynamic Time Warping (DTW) is used for matching pairs of sequences and celebrated in applications such as forecasting the evolution of time series, clustering time series or even matching sequence pairs in few-shot action recognition. The…

Computer Vision and Pattern Recognition · Computer Science 2022-11-02 Lei Wang , Piotr Koniusz

Quasars exhibit stochastic variability across wavelengths, typically well described by a Damped Random Walk (DRW). Occasionally, however, they undergo extreme luminosity changes--known as flares--that represent significant departures from…

Instrumentation and Methods for Astrophysics · Physics 2026-04-15 Atal Agrawal

The optical light curves of many quasars show variations of tenths of a magnitude or more on time scales of months to years. This variation often cannot be described well by a simple deterministic model. We perform a Bayesian comparison of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Rene Andrae , Dae-Won Kim , Coryn A. L. Bailer-Jones

We discuss large deviation properties of continuous-time random walks (CTRW) and present a general expression for the large deviation rate in CTRW in terms of the corresponding rates for the distributions of steps' lengths and waiting…

Statistical Mechanics · Physics 2021-04-14 Adrian Pacheco-Pozo , Igor M. Sokolov

A multifractal random walk (MRW) is defined by a Brownian motion subordinated by a class of continuous multifractal random measures $M[0,t], 0\le t\le1$. In this paper we obtain an extension of this process, referred to as multifractal…

Probability · Mathematics 2008-12-18 Carenne Ludeña

This work explores Doppler information from a millimetre-Wave (mm-W) Frequency-Modulated Continuous-Wave (FMCW) scanning radar to make odometry estimation more robust and accurate. Firstly, doppler information is added to the scan masking…

Robotics · Computer Science 2023-12-15 Fraser Rennie , David Williams , Paul Newman , Daniele De Martini

We consider continuous time random walks (CTRW) for open systems that exchange energy and matter with multiple reservoirs. Each waiting time distribution (WTD) for times between steps is characterized by a positive parameter a, which is set…

Statistical Mechanics · Physics 2010-03-01 Massimiliano Esposito , Katja Lindenberg

Quasars are bright and unobscured active galactic nuclei (AGN) thought to be powered by the accretion of matter around supermassive black holes at the centers of galaxies. The temporal variability of a quasar's brightness contains valuable…

Significant progress in the description of quasar variability has been recently made by employing SDSS and POSS data. Common to most studies is a fundamental assumption that photometric observations at two epochs for a large number of…

Astrophysics · Physics 2009-11-13 C. MacLeod , Z. Ivezic , W. de Vries , B. Sesar , A. Becker

Open quantum walks (OQWs) are a new type of quantum walks which are entirely driven by the dissipative interaction with external environments and are formulated as completely positive trace-preserving maps on graphs. A generalized quantum…

Quantum Physics · Physics 2020-04-06 Ayanda Romanis Zungu , IIya Sinayskiy , Francesco Petruccione

The concept of continuous-time random walks (CTRW) is a generalization of ordinary random walk models, and it is a powerful tool for investigating a broad spectrum of phenomena in natural, engineering, social and economic sciences.…

Statistical Mechanics · Physics 2015-06-12 Hamid Teimouri , Anatoly B. Kolomeisky

We present the first rigorous quantitative analysis of once-reinforced random walks (ORRW) on general graphs, based on a novel change of measure formula.~This enables us to prove large deviations estimates for the range of the walk to have…

Probability · Mathematics 2025-09-05 Andrea Collevecchio , Pierre Tarrès

Random walks provide a simple conventional model to describe various transport processes, for example propagation of heat or diffusion of matter through a medium. However, in many practical cases the medium is highly irregular due to…

Probability · Mathematics 2019-06-10 L. V. Bogachev

The role of classical noise in quantum walks (QW) on integers is investigated in the form of discrete dichotomic random variable affecting its reshuffling matrix parametrized as a SU2)/U(1) coset element. Analysis in terms of quantum…

Quantum Physics · Physics 2015-06-05 D. Ellinas , A. J. Bracken , I. Smyrnakis

We modified the broadband photometric reverberation mapping (PRM) code, JAVELIN, and tested the availability to get broad line region (BLR) time delays that are consistent with the spectroscopic reverberation mapping (SRM) project SDSS-RM.…

Astrophysics of Galaxies · Physics 2018-02-14 Haowen Zhang , Qian Yang , Xue-Bing Wu

Time series data analytics has been a problem of substantial interests for decades, and Dynamic Time Warping (DTW) has been the most widely adopted technique to measure dissimilarity between time series. A number of global-alignment kernels…

Machine Learning · Computer Science 2018-09-17 Lingfei Wu , Ian En-Hsu Yen , Jinfeng Yi , Fangli Xu , Qi Lei , Michael Witbrock

We analyze a sample of optical light curves for 100 quasars, 70 of which have black hole mass estimates. Our sample is the largest and broadest used yet for modeling quasar variability. The sources in our sample have z < 2.8 and 10^6 < M_BH…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-28 Brandon C. Kelly , Jill Bechtold , Aneta Siemiginowska
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