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Sample records for pointwise ergodic theo

  1. Strong ergodic theorem for commutative semigroup of non ...

    Indian Academy of Sciences (India)

    M Azhini

    2017-08-14

    Aug 14, 2017 ... group of asymptotically nonexpansive in the intermediate sense mappings in a uniformly convex multi-Banach space. Our results enable us to handle simultaneously ergodic theo- rem for asymptotically nonexpansive type mappings and semigroups in the intermediate sense, i.e., we can establish the ...

  2. A stochastic Ergodic Theorem in Von-Neumann algebras | Tijani ...

    African Journals Online (AJOL)

    In this paper we introduce the notion of stochastic convergence of τ- measurable operators and prove a noncommutative extension of pointwise ergodic theorem of G. D. Birkhoff by means of it by using the techniques developed by Petz in [12] Journal of the Nigerian Association of Mathematical Physics Vol. 9 2005: pp.

  3. Vector Valued Martingale-Ergodic and Ergodic-Martingale Theorems

    OpenAIRE

    Shahidi, Farruh; Ganiev, Inomjon

    2012-01-01

    We prove martingale-ergodic and ergodic-martingale theorems for vector valued Bochner integrable functions. We obtain dominant and maximal inequalities. We also prove weighted and multiparameter martingale-ergodic and ergodic martingale theorems.

  4. Lectures on ergodic theory

    CERN Document Server

    Halmos, Paul R

    2017-01-01

    This concise classic by a well-known master of mathematical exposition covers recurrence, ergodic theorems, ergodicity and mixing properties, and the relation between conjugacy and equivalence. 1956 edition.

  5. Basic ergodic theory

    CERN Document Server

    Nadkarni, M G

    2013-01-01

    This is an introductory book on Ergodic Theory. The presentation has a slow pace and the book can be read by any person with a background in basic measure theory and metric topology. A new feature of the book is that the basic topics of Ergodic Theory such as the Poincare recurrence lemma, induced automorphisms and Kakutani towers, compressibility and E. Hopf's theorem, the theorem of Ambrose on representation of flows are treated at the descriptive set-theoretic level before their measure-theoretic or topological versions are presented. In addition, topics around the Glimm-Effros theorem are discussed. In the third edition a chapter entitled 'Additional Topics' has been added. It gives Liouville's Theorem on the existence of invariant measure, entropy theory leading up to Kolmogorov-Sinai Theorem, and the topological dynamics proof of van der Waerden's theorem on arithmetical progressions.

  6. Ergodic theory and dynamical systems

    CERN Document Server

    Coudène, Yves

    2016-01-01

    This textbook is a self-contained and easy-to-read introduction to ergodic theory and the theory of dynamical systems, with a particular emphasis on chaotic dynamics. This book contains a broad selection of topics and explores the fundamental ideas of the subject. Starting with basic notions such as ergodicity, mixing, and isomorphisms of dynamical systems, the book then focuses on several chaotic transformations with hyperbolic dynamics, before moving on to topics such as entropy, information theory, ergodic decomposition and measurable partitions. Detailed explanations are accompanied by numerous examples, including interval maps, Bernoulli shifts, toral endomorphisms, geodesic flow on negatively curved manifolds, Morse-Smale systems, rational maps on the Riemann sphere and strange attractors. Ergodic Theory and Dynamical Systems will appeal to graduate students as well as researchers looking for an introduction to the subject. While gentle on the beginning student, the book also contains a number of commen...

  7. Convergence of multiple ergodic averages

    OpenAIRE

    Host, Bernard

    2006-01-01

    These notes are based on a course for a general audience given at the Centro de Modeliamento Matem\\'atico of the University of Chile, in December 2004. We study the mean convergence of multiple ergodic averages, that is, averages of a product of functions taken at different times. We also describe the relations between this area of ergodic theory and some classical and some recent results in additive number theory.

  8. The pointwise Hellmann-Feynman theorem

    Directory of Open Access Journals (Sweden)

    David Carfì

    2010-02-01

    Full Text Available In this paper we study from a topological point of view the Hellmann-Feynman theorem of Quantum Mechanics. The goal of the paper is twofold: On one hand we emphasize the role of the strong topology in the classic version of the theorem in Hilbert spaces, for what concerns the kind of convergence required on the space of continuous linear endomorphisms, which contains the space of (continuous observables.On the other hand we state and prove a new pointwise version of the classic Hellmann-Feynman theorem. This new version is not yet present in the literature and follows the idea of A. Bohm concerning the topology which is desiderable to use in Quantum Mechanics. It is indeed out of question that this non-trivial new version of the Hellmann-Feynman theorem is the ideal one - for what concerns the continuous observables on Hilbert spaces, both from a theoretical point of view, since it is the strongest version obtainable in this context - we recall that the pointwise topology is the coarsest one compatible with the linear structure of the space of continuous observables -, and from a practical point of view, because the pointwise topology is the easiest to use among topologies: it brings back the problems to the Hilbert space topology. Moreover, we desire to remark that this basic theorem of Quantum Mechanics, in his most desiderable form, is deeply interlaced with two cornerstones of Functional Analysis: the Banach-Steinhaus theorem and the Baire theorem.

  9. Ergodic averages via dominating processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Mengersen, Kerrie

    2006-01-01

    We show how the mean of a monotone function (defined on a state space equipped with a partial ordering) can be estimated, using ergodic averages calculated from upper and lower dominating processes of a stationary irreducible Markov chain. In particular, we do not need to simulate the stationary...... Markov chain and we eliminate the problem of whether an appropriate burn-in is determined or not. Moreover, when a central limit theorem applies, we show how confidence intervals for the mean can be estimated by bounding the asymptotic variance of the ergodic average based on the equilibrium chain....

  10. Pointwise probability reinforcements for robust statistical inference.

    Science.gov (United States)

    Frénay, Benoît; Verleysen, Michel

    2014-02-01

    Statistical inference using machine learning techniques may be difficult with small datasets because of abnormally frequent data (AFDs). AFDs are observations that are much more frequent in the training sample that they should be, with respect to their theoretical probability, and include e.g. outliers. Estimates of parameters tend to be biased towards models which support such data. This paper proposes to introduce pointwise probability reinforcements (PPRs): the probability of each observation is reinforced by a PPR and a regularisation allows controlling the amount of reinforcement which compensates for AFDs. The proposed solution is very generic, since it can be used to robustify any statistical inference method which can be formulated as a likelihood maximisation. Experiments show that PPRs can be easily used to tackle regression, classification and projection: models are freed from the influence of outliers. Moreover, outliers can be filtered manually since an abnormality degree is obtained for each observation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. On the entangled ergodic theorem

    NARCIS (Netherlands)

    Eisner, T.; Kunszenti-kovács, D.

    2013-01-01

    We study the convergence of the so-called entangled ergodic averages 1 Nk !N n1,...,nk=1 T n!(m) m Am−1T n!(m−1) m−1 Am−2 . . . A1T n!(1) 1 , where k " m and ! : {1, . . . ,m} #{1, . . . , k} is a surjective map.We show that, on general Banach spaces and without any restriction on the partition !,

  12. Operator theoretic aspects of ergodic theory

    CERN Document Server

    Eisner, Tanja; Haase, Markus; Nagel, Rainer

    2015-01-01

    Stunning recent results by Host–Kra, Green–Tao, and others, highlight the timeliness of this systematic introduction to classical ergodic theory using the tools of operator theory. Assuming no prior exposure to ergodic theory, this book provides a modern foundation for introductory courses on ergodic theory, especially for students or researchers with an interest in functional analysis. While basic analytic notions and results are reviewed in several appendices, more advanced operator theoretic topics are developed in detail, even beyond their immediate connection with ergodic theory. As a consequence, the book is also suitable for advanced or special-topic courses on functional analysis with applications to ergodic theory. Topics include: •an intuitive introduction to ergodic theory •an introduction to the basic notions, constructions, and standard examples of topological dynamical systems •Koopman operators, Banach lattices, lattice and algebra homomorphisms, and the Gelfand–Naimark theorem •m...

  13. The large deviations theorem and ergodicity

    International Nuclear Information System (INIS)

    Gu Rongbao

    2007-01-01

    In this paper, some relationships between stochastic and topological properties of dynamical systems are studied. For a continuous map f from a compact metric space X into itself, we show that if f satisfies the large deviations theorem then it is topologically ergodic. Moreover, we introduce the topologically strong ergodicity, and prove that if f is a topologically strongly ergodic map satisfying the large deviations theorem then it is sensitively dependent on initial conditions

  14. The ergodic theory of lattice subgroups

    CERN Document Server

    Gorodnik, Alexander

    2010-01-01

    The results established in this book constitute a new departure in ergodic theory and a significant expansion of its scope. Traditional ergodic theorems focused on amenable groups, and relied on the existence of an asymptotically invariant sequence in the group, the resulting maximal inequalities based on covering arguments, and the transference principle. Here, Alexander Gorodnik and Amos Nevo develop a systematic general approach to the proof of ergodic theorems for a large class of non-amenable locally compact groups and their lattice subgroups. Simple general conditions on the spectral theory of the group and the regularity of the averaging sets are formulated, which suffice to guarantee convergence to the ergodic mean

  15. Rapid pointwise stabilization of vibrating strings and beams

    Directory of Open Access Journals (Sweden)

    Alia BARHOUMI

    2009-11-01

    Full Text Available Applying a general construction and using former results on the observability we prove, under rather general assumptions, a rapid pointwise stabilization of vibrating strings and beams.

  16. Speckle dynamics under ergodicity breaking

    Science.gov (United States)

    Sdobnov, Anton; Bykov, Alexander; Molodij, Guillaume; Kalchenko, Vyacheslav; Jarvinen, Topias; Popov, Alexey; Kordas, Krisztian; Meglinski, Igor

    2018-04-01

    Laser speckle contrast imaging (LSCI) is a well-known and versatile approach for the non-invasive visualization of flows and microcirculation localized in turbid scattering media, including biological tissues. In most conventional implementations of LSCI the ergodic regime is typically assumed valid. However, most composite turbid scattering media, especially biological tissues, are non-ergodic, containing a mixture of dynamic and static centers of light scattering. In the current study, we examined the speckle contrast in different dynamic conditions with the aim of assessing limitations in the quantitative interpretation of speckle contrast images. Based on a simple phenomenological approach, we introduced a coefficient of speckle dynamics to quantitatively assess the ratio of the dynamic part of a scattering medium to the static one. The introduced coefficient allows one to distinguish real changes in motion from the mere appearance of static components in the field of view. As examples of systems with static/dynamic transitions, thawing and heating of Intralipid samples were studied by the LSCI approach.

  17. Ergodicity of the generalized lemon billiards

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jingyu [Department of Computer Science, University of Illinois at Urbana-Champaign, Champaign, Illinois 61801-2302 (United States); Mohr, Luke; Zhang, Hong-Kun, E-mail: hongkun@math.umass.edu; Zhang, Pengfei [Department of Mathematics and Statistics, UMass Amherst, Amherst, Massachusetts 01003 (United States)

    2013-12-15

    In this paper, we study a two-parameter family of convex billiard tables, by taking the intersection of two round disks (with different radii) in the plane. These tables give a generalization of the one-parameter family of lemon-shaped billiards. Initially, there is only one ergodic table among all lemon tables. In our generalized family, we observe numerically the prevalence of ergodicity among the some perturbations of that table. Moreover, numerical estimates of the mixing rate of the billiard dynamics on some ergodic tables are also provided.

  18. Enhancement of Visual Field Predictions with Pointwise Exponential Regression (PER) and Pointwise Linear Regression (PLR).

    Science.gov (United States)

    Morales, Esteban; de Leon, John Mark S; Abdollahi, Niloufar; Yu, Fei; Nouri-Mahdavi, Kouros; Caprioli, Joseph

    2016-03-01

    The study was conducted to evaluate threshold smoothing algorithms to enhance prediction of the rates of visual field (VF) worsening in glaucoma. We studied 798 patients with primary open-angle glaucoma and 6 or more years of follow-up who underwent 8 or more VF examinations. Thresholds at each VF location for the first 4 years or first half of the follow-up time (whichever was greater) were smoothed with clusters defined by the nearest neighbor (NN), Garway-Heath, Glaucoma Hemifield Test (GHT), and weighting by the correlation of rates at all other VF locations. Thresholds were regressed with a pointwise exponential regression (PER) model and a pointwise linear regression (PLR) model. Smaller root mean square error (RMSE) values of the differences between the observed and the predicted thresholds at last two follow-ups indicated better model predictions. The mean (SD) follow-up times for the smoothing and prediction phase were 5.3 (1.5) and 10.5 (3.9) years. The mean RMSE values for the PER and PLR models were unsmoothed data, 6.09 and 6.55; NN, 3.40 and 3.42; Garway-Heath, 3.47 and 3.48; GHT, 3.57 and 3.74; and correlation of rates, 3.59 and 3.64. Smoothed VF data predicted better than unsmoothed data. Nearest neighbor provided the best predictions; PER also predicted consistently more accurately than PLR. Smoothing algorithms should be used when forecasting VF results with PER or PLR. The application of smoothing algorithms on VF data can improve forecasting in VF points to assist in treatment decisions.

  19. A computer program for the pointwise functions generation

    International Nuclear Information System (INIS)

    Caldeira, Alexandre D.

    1995-01-01

    A computer program that was developed with the objective of generating pointwise functions, by a combination of tabulated values and/or mathematical expressions, to be used as weighting functions for nuclear data is presented. This simple program can be an important tool for researchers involved in group constants generation. (author). 5 refs, 2 figs

  20. The ergodicity landscape of quantum theories

    Science.gov (United States)

    Ho, Wen Wei; Radičević, Đorđe

    2018-02-01

    This paper is a physicist’s review of the major conceptual issues concerning the problem of spectral universality in quantum systems. Here, we present a unified, graph-based view of all archetypical models of such universality (billiards, particles in random media, interacting spin or fermion systems). We find phenomenological relations between the onset of ergodicity (Gaussian-random delocalization of eigenstates) and the structure of the appropriate graphs, and we construct a heuristic picture of summing trajectories on graphs that describes why a generic interacting system should be ergodic. We also provide an operator-based discussion of quantum chaos and propose criteria to distinguish bases that can usefully diagnose ergodicity. The result of this analysis is a rough but systematic outline of how ergodicity changes across the space of all theories with a given Hilbert space dimension. As a particular example, we study the SYK model and report on the transition from maximal to partial ergodicity as the disorder strength is decreased.

  1. Quantum ergodicity in the SYK model

    Science.gov (United States)

    Altland, Alexander; Bagrets, Dmitry

    2018-05-01

    We present a replica path integral approach describing the quantum chaotic dynamics of the SYK model at large time scales. The theory leads to the identification of non-ergodic collective modes which relax and eventually give way to an ergodic long time regime (describable by random matrix theory). These modes, which play a role conceptually similar to the diffusion modes of dirty metals, carry quantum numbers which we identify as the generators of the Clifford algebra: each of the 2N different products that can be formed from N Majorana operators defines one effective mode. The competition between a decay rate quickly growing in the order of the product and a density of modes exponentially growing in the same parameter explains the characteristics of the system's approach to the ergodic long time regime. We probe this dynamics through various spectral correlation functions and obtain favorable agreement with existing numerical data.

  2. Ergodic Theory, Open Dynamics, and Coherent Structures

    CERN Document Server

    Bose, Christopher; Froyland, Gary

    2014-01-01

    This book is comprised of selected research articles developed from a workshop on Ergodic Theory, Probabilistic Methods and Applications, held in April 2012 at the Banff International Research Station. It contains contributions from world leading experts in ergodic theory, dynamical systems, numerical analysis, fluid dynamics, and networks. The volume will serve as a valuable reference for mathematicians, physicists, engineers, physical oceanographers, atmospheric scientists, biologists, and climate scientists, who currently use, or wish to learn how to use, probabilistic techniques to cope with dynamical models that display open, coherent, or non-equilibrium behavior.

  3. Ergodicity of a single particle confined in a nanopore

    DEFF Research Database (Denmark)

    Bernardi, S.; Hansen, Jesper Schmidt; Frascolli, F.

    2012-01-01

    -ergodic component of the phase space for energy levels typical of experiments, is surprisingly small, i.e. we conclude that the ergodic hypothesis is a reasonable approximation even for a single particle trapped in a nanopore. Due to the numerical scope of this work, our focus will be the onset of ergodic behavior...

  4. Smooth Rényi Entropy of Ergodic Quantum Information Sources

    NARCIS (Netherlands)

    Schoenmakers, Berry; Tjoelker, Jilles; Tuyls, Pim; Verbitskiy, Evgeny

    2007-01-01

    We investigate the recently introduced notion of smooth Rényi entropy for the case of ergodic information sources, thereby generalizing previous work which concentrated mainly on i.i.d. information sources. We will actually consider ergodic quantum information sources, of which ergodic classical

  5. Improving Signal Detection using Allan and Theo Variances

    Science.gov (United States)

    Hardy, Andrew; Broering, Mark; Korsch, Wolfgang

    2017-09-01

    Precision measurements often deal with small signals buried within electronic noise. Extracting these signals can be enhanced through digital signal processing. Improving these techniques provide signal to noise ratios. Studies presently performed at the University of Kentucky are utilizing the electro-optic Kerr effect to understand cell charging effects within ultra-cold neutron storage cells. This work is relevant for the neutron electric dipole moment (nEDM) experiment at Oak Ridge National Laboratory. These investigations, and future investigations in general, will benefit from the illustrated improved analysis techniques. This project will showcase various methods for determining the optimum duration that data should be gathered for. Typically, extending the measuring time of an experimental run reduces the averaged noise. However, experiments also encounter drift due to fluctuations which mitigate the benefits of extended data gathering. Through comparing FFT averaging techniques, along with Allan and Theo variance measurements, quantifiable differences in signal detection will be presented. This research is supported by DOE Grants: DE-FG02-99ER411001, DE-AC05-00OR22725.

  6. Ergodic Interference Alignment with Delayed Feedback

    OpenAIRE

    Kang, Myung Gil; Choi, Wan

    2013-01-01

    We propose new ergodic interference alignment techniques for $K$-user interference channels with delayed feedback. Two delayed feedback scenarios are considered -- delayed channel information at transmitter (CIT) and delayed output feedback. It is proved that the proposed techniques achieve total $2K/(K+2)$ DoF which is higher than that by the retrospective interference alignment for the delayed feedback scenarios.

  7. Ergodic theory of amenable semigroup actions

    Indian Academy of Sciences (India)

    ) (1984). [16] Riazi A and Wong J C S, Characterizations of amenable locally compact semigroups,. Pacific J. Math. 108 (1983) 479–496. [17] Rudin W, Functional analysis (New York: McGraw Hill) (1991). [18] Wong J C S, An ergodic property ...

  8. Boundary plasma control with the ergodic divertor

    International Nuclear Information System (INIS)

    Ghendrih, Ph.; Becoulet, M.; Beyer, P.

    1999-01-01

    Ergodic divertor experiments on Tore Supra provide evidence of significant control of plasma-wall interaction. Theoretical investigation of the laminar region (i.e. governed by parallel transport) indicates that control of the plasma state at the target plate can be achieved with plasma states similar to that observed with the axisymmetric divertor. Analysis of the temperature field with a 2-D test particle code allows one to recover the observed spatial modulation and shows that an intrinsic barrier appears to develop at the separatrix. Energy deposition peaking, analysed with a 3-D code, is strongly reduced when moderate transverse transport is considered. Possible control of upstream parameters can thus be achieved in the ergodic region, for instance a lowering of the parallel energy flux by cross field transport. (author)

  9. Boundary plasma control with the ergodic divertor

    International Nuclear Information System (INIS)

    Ghendrih, Ph.; Becoulet, M.; Beyer, P.

    2001-01-01

    Ergodic divertor experiments on Tore Supra provide evidence of significant control of plasma-wall interaction. Theoretical investigation of the laminar region (i.e. governed by parallel transport) indicates that control of the plasma state at the target plate can be achieved with plasma states similar to that observed with the axisymmetric divertor. Analysis of the temperature field with a 2-D test particle code allows one to recover the observed spatial modulation and shows that an intrinsic barrier appears to develop at the separatrix. Energy deposition peaking, analysed with a 3-D code, is strongly reduced when moderate transverse transport is considered. Possible control of upstream parameters can thus be achieved in the ergodic region, for instance a lowering of the parallel energy flux by cross field transport. (author)

  10. Probability, random processes, and ergodic properties

    CERN Document Server

    Gray, Robert M

    1988-01-01

    This book has been written for several reasons, not all of which are academic. This material was for many years the first half of a book in progress on information and ergodic theory. The intent was and is to provide a reasonably self-contained advanced treatment of measure theory, prob ability theory, and the theory of discrete time random processes with an emphasis on general alphabets and on ergodic and stationary properties of random processes that might be neither ergodic nor stationary. The intended audience was mathematically inc1ined engineering graduate students and visiting scholars who had not had formal courses in measure theoretic probability . Much of the material is familiar stuff for mathematicians, but many of the topics and results have not previously appeared in books. The original project grew too large and the first part contained much that would likely bore mathematicians and dis courage them from the second part. Hence I finally followed the suggestion to separate the material and split...

  11. Are there ergodic limits to evolution? Ergodic exploration of genome space and convergence.

    Science.gov (United States)

    McLeish, Tom C B

    2015-12-06

    We examine the analogy between evolutionary dynamics and statistical mechanics to include the fundamental question of ergodicity-the representative exploration of the space of possible states (in the case of evolution this is genome space). Several properties of evolutionary dynamics are identified that allow a generalization of the ergodic dynamics, familiar in dynamical systems theory, to evolution. Two classes of evolved biological structure then arise, differentiated by the qualitative duration of their evolutionary time scales. The first class has an ergodicity time scale (the time required for representative genome exploration) longer than available evolutionary time, and has incompletely explored the genotypic and phenotypic space of its possibilities. This case generates no expectation of convergence to an optimal phenotype or possibility of its prediction. The second, more interesting, class exhibits an evolutionary form of ergodicity-essentially all of the structural space within the constraints of slower evolutionary variables have been sampled; the ergodicity time scale for the system evolution is less than the evolutionary time. In this case, some convergence towards similar optima may be expected for equivalent systems in different species where both possess ergodic evolutionary dynamics. When the fitness maximum is set by physical, rather than co-evolved, constraints, it is additionally possible to make predictions of some properties of the evolved structures and systems. We propose four structures that emerge from evolution within genotypes whose fitness is induced from their phenotypes. Together, these result in an exponential speeding up of evolution, when compared with complete exploration of genomic space. We illustrate a possible case of application and a prediction of convergence together with attaining a physical fitness optimum in the case of invertebrate compound eye resolution.

  12. Pointwise intensity-based dynamic speckle analysis with binary patterns

    Science.gov (United States)

    Stoykova, Elena; Mateev, Georgy; Nazarova, Dimana; Berberova, Nataliya; Ivanov, Branimir

    2017-06-01

    Non-destructive detection of physical or biological activity through statistical processing of speckle patterns on the surface of diffusely reflecting objects is an area of active research. A lot of pointwise intensity-based algorithms have been proposed over the recent years. Efficiency of these algorithms is deteriorated by the signal-dependent speckle data, non-uniform illumination or varying reflectivity across the object, especially when the number of the acquired speckle patterns is limited. Pointwise processing of a sequence of 2D images is also time-consuming. In this paper, we propose to transform the acquired speckle images into binary patterns by using for a sign threshold the mean intensity value estimated at each spatial point from the temporal sequence of intensities at this point. Activity is characterized by the 2D distribution of a temporal polar correlation function estimated at a given time lag from the binary patterns. Processing of synthetic and experimental data confirmed that the algorithm provided correct activity determination with the same accuracy as the temporal normalized correlation function. It is efficient without the necessity to apply normalization at non-uniform distribution of intensity in the illuminating laser beam and offers acceleration of computation.

  13. Refinement of pointwise linear regression criteria for determining glaucoma progression.

    Science.gov (United States)

    Kummet, Colleen M; Zamba, K D; Doyle, Carrie K; Johnson, Chris A; Wall, Michael

    2013-09-19

    A variety of pointwise linear regression (PLR) criteria have been proposed for determining glaucomatous visual field progression. However, alternative PLR criteria have only been assessed on a limited basis. The purpose of this study was to evaluate a range of PLR slope and significance criteria to define a clinically useful progression decision rule for longitudinal visual field examinations. Visual field data for each of 140 eyes (one per participant among 96 cases and 44 controls) were evaluated using the Humphrey Field Analyzer II program 24-2 Swedish interactive thresholding algorithm standard test strategy and Goldmann size III stimuli. The pointwise linear regression A2 (PLRA2) method was used to analyze the data, which included nine visual field examinations performed every 6 months for 4 years. Data from the Ocular Hypertension Treatment Study (OHTS) were used to validate the decision rule. Several slope criteria produced specificities of 0.90 or higher, particularly slope criteria of less than -1.2 dB/y. The use of the slope criterion less than -1.2 dB/y at a significance level of P refined by requiring a stricter slope criterion such as less than -1.2 dB/y and relaxing the significance criterion to P < 0.04. Increasing the hit rate of PLR will be useful for early detection and treatment of glaucoma.

  14. On Pointwise Approximation of Conjugate Functions by Some Hump Matrix Means of Conjugate Fourier Series

    Directory of Open Access Journals (Sweden)

    W. Łenski

    2015-01-01

    Full Text Available The results generalizing some theorems on N, pnE, γ summability are shown. The same degrees of pointwise approximation as in earlier papers by weaker assumptions on considered functions and examined summability methods are obtained. From presented pointwise results, the estimation on norm approximation is derived. Some special cases as corollaries are also formulated.

  15. Convective Replica-Exchange in Ergodic Regimes.

    Science.gov (United States)

    Signorini, Giorgio F; Giovannelli, Edoardo; Spill, Yannick G; Nilges, Michael; Chelli, Riccardo

    2014-03-11

    In a recent article (J. Comput. Chem. 2013, 34, 132-140), convective replica-exchange (convective-RE) has been presented as an alternative to the standard even-odd transition scheme. Computations on systems of various complexity have shown that convective-RE may increase the number of replica round-trips in temperature space with respect to the standard exchange scheme, leading to a more effective sampling of energy basins. Moreover, it has been shown that the method may prevent the formation of bottlenecks in the diffusive walk of replicas through the space of temperature states. By using an ideal temperature-RE model and a classical harmonic-oscillator RE scheme, we study the performances of convective-RE when ergodicity is not broken and convergence of acceptance probabilities is attained. In this dynamic regime, the round-trip ratio between convective and standard-RE is at maximum ∼ 1.5, a value much smaller than that observed in nonergodic simulations. For large acceptance probabilities, the standard-RE outperforms convective-RE. Our observations suggest that convective-RE can safely be used in either ergodic or non-ergodic regimes; however, convective-RE is advantageous only when bottlenecks occur in the state-space diffusion of replicas, or when acceptance probabilities are globally low. We also show that decoupling of the state-space dynamics of the stick replica from the dynamics of the remaining replicas improves the efficiency of convective-RE at low acceptance probability regimes.

  16. A posteriori pointwise error estimates for the boundary element method

    Energy Technology Data Exchange (ETDEWEB)

    Paulino, G.H. [Cornell Univ., Ithaca, NY (United States). School of Civil and Environmental Engineering; Gray, L.J. [Oak Ridge National Lab., TN (United States); Zarikian, V. [Univ. of Central Florida, Orlando, FL (United States). Dept. of Mathematics

    1995-01-01

    This report presents a new approach for a posteriori pointwise error estimation in the boundary element method. The estimator relies upon the evaluation of hypersingular integral equations, and is therefore intrinsic to the boundary integral equation approach. This property allows some theoretical justification by mathematically correlating the exact and estimated errors. A methodology is developed for approximating the error on the boundary as well as in the interior of the domain. In the interior, error estimates for both the function and its derivatives (e.g. potential and interior gradients for potential problems, displacements and stresses for elasticity problems) are presented. Extensive computational experiments have been performed for the two dimensional Laplace equation on interior domains, employing Dirichlet and mixed boundary conditions. The results indicate that the error estimates successfully track the form of the exact error curve. Moreover, a reasonable estimate of the magnitude of the actual error is also obtained.

  17. A Point-Wise Quantification of Asymmetry Using Deformation Fields

    DEFF Research Database (Denmark)

    Ólafsdóttir, Hildur; Lanche, Stephanie; Darvann, Tron Andre

    2007-01-01

    of the resulting displacement vectors on the left and right side of the symmetry plane, gives a point-wise measure of asymmetry. The asymmetry measure was applied to the study of Crouzon syndrome using Micro CT scans of genetically modified mice. Crouzon syndrome is characterised by the premature fusion of cranial...... sutures, which gives rise to a highly asymmetric growth. Quantification and localisation of this asymmetry is of high value with respect to surgery planning and treatment evaluation. Using the proposed method, asymmetry was calculated in each point of the surface of Crouzon mice and wild-type mice...... (controls). Asymmetry appeared in similar regions for the two groups but the Crouzon mice were found significantly more asymmetric. The localisation ability of the method was in good agreement with ratings from a clinical expert. Validating the quantification ability is a less trivial task due to the lack...

  18. Avoiding ergodicity and turbulence in R3 vector fields

    International Nuclear Information System (INIS)

    Ancochea, J.M.; Campoamor-Stursberg, R.; Gonzalez-Gascon, F.

    2003-01-01

    We show that analytic R 3 vector fields having the property of being transversal to either analytic functions or foliations F 2 , or parallel to a foliation, are free from ergodicity and turbulence. The absence of turbulence and ergodicity via induced vector fields is also proven

  19. Generalized continued fractions and ergodic theory

    International Nuclear Information System (INIS)

    Pustyl'nikov, L D

    2003-01-01

    In this paper a new theory of generalized continued fractions is constructed and applied to numbers, multidimensional vectors belonging to a real space, and infinite-dimensional vectors with integral coordinates. The theory is based on a concept generalizing the procedure for constructing the classical continued fractions and substantially using ergodic theory. One of the versions of the theory is related to differential equations. In the finite-dimensional case the constructions thus introduced are used to solve problems posed by Weyl in analysis and number theory concerning estimates of trigonometric sums and of the remainder in the distribution law for the fractional parts of the values of a polynomial, and also the problem of characterizing algebraic and transcendental numbers with the use of generalized continued fractions. Infinite-dimensional generalized continued fractions are applied to estimate sums of Legendre symbols and to obtain new results in the classical problem of the distribution of quadratic residues and non-residues modulo a prime. In the course of constructing these continued fractions, an investigation is carried out of the ergodic properties of a class of infinite-dimensional dynamical systems which are also of independent interest

  20. Women, Scientists, Agitators: Magazine Portrayal of Rachel Carson and Theo Colborn.

    Science.gov (United States)

    Corbett, Julia B.

    2001-01-01

    Utilizes a theoretical framework of the media's role in reporting conflict and uncertain science, and feminism and science in a thematic analysis of magazine coverage given Rachel Carson and "the Rachel Carson of '90s," Theo Colborn. Notes that Carson and Colborn's identities as women, scientists, and agitators led critics to charge that…

  1. The Effect of the Theo van Gogh Murder on House Prices in Amsterdam

    NARCIS (Netherlands)

    Gautier, Pieter A.; Siegmann, Arjen; Vuuren, van Aico

    2007-01-01

    This paper estimates the impact of the murder of film maker Theo van Gogh on November 2, 2004, on listed house prices in Amsterdam with a unique dataset. We use an hedonic-market approach to show that general attitudes towards Muslim minorities were negatively affected by the murder. Specifically,

  2. Ergodic theory of expanding thurston maps

    CERN Document Server

    Li, Zhiqiang

    2017-01-01

    Thurston maps are topological generalizations of postcritically-finite rational maps. This book provides a comprehensive study of ergodic theory of expanding Thurston maps, focusing on the measure of maximal entropy, as well as a more general class of invariant measures, called equilibrium states, and certain weak expansion properties of such maps. In particular, we present equidistribution results for iterated preimages and periodic points with respect to the unique measure of maximal entropy by investigating the number and locations of fixed points. We then use the thermodynamical formalism to establish the existence, uniqueness, and various other properties of the equilibrium state for a Holder continuous potential on the sphere equipped with a visual metric. After studying some weak expansion properties of such maps, we obtain certain large deviation principles for iterated preimages and periodic points under an additional assumption on the critical orbits of the maps. This enables us to obtain general eq...

  3. Oseledec multiplicative ergodic theorem for laminations

    CERN Document Server

    Nguyên, Viêt-Anh

    2017-01-01

    Given a n-dimensional lamination endowed with a Riemannian metric, the author introduces the notion of a multiplicative cocycle of rank d, where n and d are arbitrary positive integers. The holonomy cocycle of a foliation and its exterior powers as well as its tensor powers provide examples of multiplicative cocycles. Next, the author defines the Lyapunov exponents of such a cocycle with respect to a harmonic probability measure directed by the lamination. He also proves an Oseledec multiplicative ergodic theorem in this context. This theorem implies the existence of an Oseledec decomposition almost everywhere which is holonomy invariant. Moreover, in the case of differentiable cocycles the author establishes effective integral estimates for the Lyapunov exponents. These results find applications in the geometric and dynamical theory of laminations. They are also applicable to (not necessarily closed) laminations with singularities. Interesting holonomy properties of a generic leaf of a foliation are obtained...

  4. Ergodic directional switching in mobile insect groups

    KAUST Repository

    Escudero, Carlos

    2010-07-29

    We obtain a Fokker-Planck equation describing experimental data on the collective motion of locusts. The noise is of internal origin and due to the discrete character and finite number of constituents of the swarm. The stationary probability distribution shows a rich phenomenology including nonmonotonic behavior of several order and disorder transition indicators in noise intensity. This complex behavior arises naturally as a result of the randomness in the system. Its counterintuitive character challenges standard interpretations of noise induced transitions and calls for an extension of this theory in order to capture the behavior of certain classes of biologically motivated models. Our results suggest that the collective switches of the group\\'s direction of motion might be due to a random ergodic effect and, as such, they are inherent to group formation. © 2010 The American Physical Society.

  5. A Pointwise Dimension Analysis of the Las Campanas Redshift Survey

    Science.gov (United States)

    Best, J. S.

    1999-12-01

    The modern motivation for fractal geometry may best be summed up by this quote of Benoit Mandelbrot: ``Mountains are not cones, clouds are not spheres, coastlines are not circles, and bark is not smooth, nor does lightning travel in a straight line.'' Fractals are, in simplest terms, ``objects which are (approximately) self-similar on all scales.'' The renewed modern interest in fractals has found as one of its applications the study of large-scale structure, giving a quantitative descriptive scheme to ideas that had been expressed qualitatively as early as the 1920s. This paper presents the preliminary results of an analysis of the structure of the Las Campanas Redshift Survey, or LCRS. LCRS is an approximately 26000 galaxy survey (surveyed as six declination slices) that has been studied extensively over the past few years, with an eye towards understanding large-scale structure. For this analysis, I have used the pointwise dimension, an easy-to-apply fractal statistic which has been previously used to study cluster interiors, galactic distributions, and cluster distributions. The present analysis has been performed to serve as a guide for the study of future large redshift surveys. This research has been funded by National Science Foundation grant AST-9808608.

  6. Stress-induced alterations of left-right electrodermal activity coupling indexed by pointwise transinformation

    Czech Academy of Sciences Publication Activity Database

    Světlák, M.; Bob, P.; Roman, R.; Ježek, S.; Damborská, A.; Chládek, Jan; Shaw, D. J.; Kukleta, M.

    2013-01-01

    Roč. 62, č. 6 (2013), s. 711-719 ISSN 0862-8408 Institutional support: RVO:68081731 Keywords : electrodermal activity * pointwise trasinformation * autonomic nervous system * asymmetry * stress Subject RIV: CE - Biochemistry Impact factor: 1.487, year: 2013

  7. Uniform ergodicities and perturbation bounds of Markov chains on ordered Banach spaces

    Science.gov (United States)

    Erkursun Özcan, Nazife; Mukhamedov, Farrukh

    2017-03-01

    In this paper, we consider uniformly mean ergodic and uniformly asymptotical stable Markov operators on ordered Banach spaces. In terms of the ergodicity coefficient, we show the equivalence of uniform and weak mean ergodicities of Markov operators. This result allowed us to establish a category theorem for uniformly mean ergodic Markov operators. Furthermore, using properties of the ergodicity coefficient, we develop the perturbation theory for uniformly asymptotical stable Markov chains in the abstract scheme.

  8. On reducibility and ergodicity of population projection matrix models

    DEFF Research Database (Denmark)

    Stott, Iain; Townley, Stuart; Carslake, David

    2010-01-01

    1. Population projection matrices (PPMs) are probably the most commonly used empirical population models. To be useful for predictive or prospective analyses, PPM models should generally be irreducible (the associated life cycle graph contains the necessary transition rates to facilitate pathways...... structure used in the population projection). In our sample of published PPMs, 15·6% are non-ergodic. 3. This presents a problem: reducible–ergodic models often defy biological rationale in their description of the life cycle but may or may not prove problematic for analysis as they often behave similarly...... to irreducible models. Reducible–non-ergodic models will usually defy biological rationale in their description of the both the life cycle and population dynamics, hence contravening most analytical methods. 4. We provide simple methods to evaluate reducibility and ergodicity of PPM models, present illustrative...

  9. De miskenning van Theo van Doesburg; zijn bijdrage tot de ontwikkeling van de konkrete poëzie

    OpenAIRE

    J. van der Elst

    1987-01-01

    More literary critics outside Belgium and the Netherlands have written about Theo van Doesburg than from inside these countries. The first important monograph on him appeared in English - Theo van Doesburg - Propagandist and Practitioner of the Avant-Garde, 1909-1923, by Hannah Hedrick. Van Doesburg’s poetry developed in the direction of concrete poetry - the type of poetry in which the spatial, acoustic and visual characteristics of language are maximally utilized towards the creation of the...

  10. Non-ergodicity of Nosé-Hoover dynamics

    Science.gov (United States)

    Legoll, Frédéric; Luskin, Mitchell; Moeckel, Richard

    2009-07-01

    The Nosé-Hoover dynamics is a deterministic method that is commonly used to sample the canonical Gibbs measure. This dynamics extends the physical Hamiltonian dynamics by the addition of a 'thermostat' variable, which is coupled nonlinearly with the physical variables. The accuracy of the method depends on the dynamics being ergodic. Numerical experiments have been published earlier that are consistent with non-ergodicity of the dynamics for some model problems. The authors recently proved the non-ergodicity of the Nosé-Hoover dynamics for the one-dimensional harmonic oscillator. In this paper, this result is extended to non-harmonic one-dimensional systems. We also show that, for some multidimensional systems, the averaged dynamics for the limit of infinite thermostat 'mass' has many invariants, thus giving theoretical support for either non-ergodicity or slow ergodization. Numerical experiments for a two-dimensional central force problem and the one-dimensional pendulum problem give evidence for non-ergodicity. This paper is published as part of a collection in honour of Todd Dupont's 65th birthday.

  11. Pointwise functions for flexible implementation of crustal deformation physics in PyLith

    Science.gov (United States)

    Aagaard, B.; Knepley, M.; Williams, C. A.

    2015-12-01

    The next stage of development for PyLith, a flexible, open-source finite-element code (http://geodynamics.org/cig/software/pylith/) for modeling quasi-static and dynamic crustal deformation with an emphasis earthquake faulting, focuses on refactoring the code to provide greater flexibility in support of a broader range of physics, discretizations, and optimizations for a variety of computer hardware. We separate the finite-element integration into a discretization-specific portion and discretization-independent pointwise functions associated with the governing equations. The discretization-specific portion is designed to accommodate arbitrary order finite elements and multiple implementations for optimization targeting specific hardware (e.g., CPU and GPU). The pointwise functions encapsulate the physics, including the governing equations and rheologies. Users can easily extend the code by adding new pointwise functions to implement different rheologies and/or governing equations. PyLith currently includes pointwise functions for quasi-static and dynamic elasticity for several elastic, viscoelastic, and elastoplastic rheologies. We plan to add pointwise functions for coupling of elasticity with fluid flow and incompressible elasticity. Tight integration with the Portable, Extensible Toolkit for Scientific Computation (PETSc) provides support for a wide range of linear and nonlinear solvers and time-stepping algorithms.

  12. International Conference on Ergodic Theory and Related Topics

    CERN Document Server

    Richter, Karin; Warstat, Volker

    1992-01-01

    The purpose of the conference was to represent recent developments in measure theoretic, differentiable and topological dynamical systems as well as connections to probability theory, stochastic processes, operator theory and statistical physics. Only original research papers that do not appear elsewhere are included in the proceedings. Their topics include: C(2)-diffeomorphisms of compact Riemann manifolds, geodesic flows, chaotic behaviour in billards, nonlinear ergodic theory, central limit theorems for subadditive processes, Hausdorff measures for parabolic rational maps, Markov operators, periods of cycles, Julia sets, ergodic theorems. From the Contents: L.A. Bunimovich: On absolutely focusing mirrors.- M. Denker, M. Urbanski: The dichotomy of Hausdorff measures and equilibrium states for parabolic rational maps.- F. Ledrappier: Ergodic properties of the stable foliations.- U. Wacker: Invariance principles and central limit theorems for nonadditive stationary processes.- J. Schmeling, R. Siegmund-Schult...

  13. Ergodic divertor impact on Tore Supra plasma edge

    International Nuclear Information System (INIS)

    Grosman, A.; Ghendrih, P.; Agostini, E.; Bruneau, J.L.; Michelis, C. De; Fall, T.; Gil, C.; Guilhem, D.; Hess, W.; Hutter, T.

    1990-01-01

    Present ergodic divertor experiments in TORE SUPRA have been devoted to benchmarking the operational regimes of the apparatus. Two major effects are reported; on one hand, strong changes occur in the ergodized boundary layer (up to 20% of the minor radius), and on the other hand, the central plasma and especially the confinement is not directly affected, i.e. the observed modifications are induced by edge effects. The basic trends, which are recorded are a decrease of both the edge electronic temperature and the edge density gradient while the radiated power is increased at the very edge of the ergodic region. The latter feature is in agreement with the impurity line emission characterized by an increase of the peripheral lines with a strong decrease of the central lines

  14. Ergodic optimization in the expanding case concepts, tools and applications

    CERN Document Server

    Garibaldi, Eduardo

    2017-01-01

    This book focuses on the interpretation of ergodic optimal problems as questions of variational dynamics, employing a comparable approach to that of the Aubry-Mather theory for Lagrangian systems. Ergodic optimization is primarily concerned with the study of optimizing probability measures. This work presents and discusses the fundamental concepts of the theory, including the use and relevance of Sub-actions as analogues to subsolutions of the Hamilton-Jacobi equation. Further, it provides evidence for the impressively broad applicability of the tools inspired by the weak KAM theory.

  15. Pointwise Multipliers on Spaces of Homogeneous Type in the Sense of Coifman and Weiss

    Directory of Open Access Journals (Sweden)

    Yanchang Han

    2014-01-01

    homogeneous type in the sense of Coifman and Weiss, pointwise multipliers of inhomogeneous Besov and Triebel-Lizorkin spaces are obtained. We make no additional assumptions on the quasi-metric or the doubling measure. Hence, the results of this paper extend earlier related results to a more general setting.

  16. Mean ergodic operators and reflexive Fréchet lattices

    NARCIS (Netherlands)

    Bonet, J.; De Pagter, B.; Ricker, W.J.

    2011-01-01

    Connections between (positive) mean ergodic operators acting in Banach lattices and properties of the underlying lattice itself are well understood (see the works of Emel'yanov, Wolff and Zaharopol). For Fréchet lattices (or more general locally convex solid Riesz spaces) there is virtually no

  17. Inspiring Collaboration: The Legacy of Theo Colborn's Transdisciplinary Research on Fracking.

    Science.gov (United States)

    Wylie, Sara; Schultz, Kim; Thomas, Deborah; Kassotis, Chris; Nagel, Susan

    2016-09-13

    This article describes Dr Theo Colborn's legacy of inspiring complementary and synergistic environmental health research and advocacy. Colborn, a founder of endocrine disruption research, also stimulated study of hydraulic fracturing (fracking). In 2014, the United States led the world in oil and gas production, with fifteen million Americans living within one mile of an oil or gas well. Colborn pioneered efforts to understand and control the impacts of this sea change in energy production. In 2005, her research organization The Endocrine Disruption Exchange (TEDX) developed a database of chemicals used in natural gas extraction and their health effects. This database stimulated novel scientific and social scientific research and informed advocacy by (1) connecting communities' diverse health impacts to chemicals used in natural gas development, (2) inspiring social science research on open-source software and hardware for citizen science, and (3) posing new scientific questions about the endocrine-disrupting properties of fracking chemicals. © The Author(s) 2016.

  18. Terrorism and attitudes towards minorities: The effect of the Theo van Gogh murder on house prices in Amsterdam

    NARCIS (Netherlands)

    Gautier, P.A.; Siegmann, A.H.; van Vuuren, A.P.

    2009-01-01

    Does fundamentalist-Islamic terrorism have an effect on the general attitudes towards Muslim minorities? We use the murder of Theo van Gogh as an event study to address this question. Specifically, we use the hedonic-market model and test for an effect on listed house prices in neighborhoods where

  19. THEOS-2 Orbit Design: Formation Flying in Equatorial Orbit and Damage Prevention Technique for the South Atlantic Magnetic Anomaly (SAMA)

    Science.gov (United States)

    Pimnoo, Ammarin

    2016-07-01

    Geo-Informatics and Space Technology Development Agency (GISTDA) has initiative THEOS-2 project after the THEOS-1 has been operated for more than 7 years which is over the lifetime already. THEOS-2 project requires not only the development of earth observation satellite(s), but also the development of the area-based decision making solution platform comprising of data, application systems, data processing and production system, IT infrastructure improvement and capacity building through development of satellites, engineering model, and infrastructures capable of supporting research in related fields. The developing satellites in THEOS-2 project are THAICHOTE-2 and THAICHOTE-3. This paper focuses the orbit design of THAICHOTE-2 & 3. It discusses the satellite orbit design for the second and third EOS of Thailand. In this paper, both THAICHOTE will be simulated in an equatorial orbit as a formation flying which will be compared the productive to THAICHOTE-1 (THEOS-1). We also consider a serious issue in equatorial orbit design, namely the issue of the geomagnetic field in the area of the eastern coast of South America, called the South Atlantic Magnetic Anomaly (SAMA). The high-energy particles of SAMA comprise a radiation environment which can travel through THAICHOTE-2 & 3 material and deposit kinetic energy. This process causes atomic displacement or leaves a stream of charged atoms in the incident particles' wake. It can cause damage to the satellite including reduction of power generated by solar arrays, failure of sensitive electronics, increased background noise in sensors, and exposure of the satellite devices to radiation. This paper demonstrates the loss of ionizing radiation damage and presents a technique to prevent damage from high-energy particles in the SAMA.

  20. Super convergence of ergodic averages for quasiperiodic orbits

    Science.gov (United States)

    Das, Suddhasattwa; Yorke, James A.

    2018-02-01

    The Birkhoff ergodic theorem asserts that time averages of a function evaluated along a trajectory of length N converge to the space average, the integral of f, as N\\to∞ , for ergodic dynamical systems. But that convergence can be slow. Instead of uniform averages that assign equal weights to points along the trajectory, we use an average with a non-uniform distribution of weights, weighting the early and late points of the trajectory much less than those near the midpoint N/2 . We show that in quasiperiodic dynamical systems, our weighted averages converge far faster provided f is sufficiently differentiable. This result can be applied to obtain efficient numerical computation of rotation numbers, invariant densities and conjugacies of quasiperiodic systems.

  1. Progress in ergodic divertor operation on Tore Supra

    International Nuclear Information System (INIS)

    Ghendrih, Ph.; Becoulet, M.; Colas, L.; Grosman, A.; Guirlet, R.; Gunn, J.; Loarer, T.; Azeroual, A.; Basiuk, V.; Beaumont, B.; Becoulet, A.; Bremond, S.; Bucalossi, J.; Capes, H.; Corre, Y.; Costanzo, L.; Michelis, C. de; Devynck, P.; Feron, S.; Friant, C.; Garbet, X.; Giannella, R.; Grisolia, C.; Hess, W.; Hogan, J.; Ladurelle, L.; Laugier, F.; Martin, G.; Mattioli, M.; Meslin, B.; Monier-Garbet, P.; Moulin, D.; Nguyen, F.; Pascal, J.Y.; Pecquet, A.L.; Pegourie, B.; Reichle, R.; Saint-Laurent, F.; Vallet, J.C.; Zabiego, M.

    1999-09-01

    Upgrade of the Tore ergodic divertor has led to significant progress in ergodic divertor physics. The disruptive limit governed by the stochastization of the outer magnetic surfaces is found to occur for a value of the Chirikov parameter reaching 2 on the magnetic surface q = 2 + 3 / 12. This experimentally observed robustness allows one to operate at very low safety factor on the separatrix (q ∼ 2). Numerical analysis of ballooning turbulence in a stochastic layer indicates that the decay of the density fluctuations is in associated with an increase of the fluctuating electric drift velocity. The bottom line is then an enhanced cross-field transport in the vicinity of the target plates. This lowering of confinement appears to be compensated by an intrinsic transport barrier on the electron temperature. The 3-D response of the temperature field is computed with a fluid code. The intrinsic transport barrier at the separatrix, reported experimentally, can be recovered together with small amplitude temperature modulations in the divertor volume. Experimental evidence of the 3 density regimes (linear, high recycling and detachment) is reported. The low critical density values for these transitions indicate that similar parallel physics govern the axisymmetric and ergodic divertor, despite the open configuration of the latter. Measurement and understanding of these density regimes provide a means for feedback control of plasma density and an improvement in ICRH coupling scenarios. Experimental data also indicated that particle control with the vented target plates is effective. Increase of impurity control and radiation efficiency are recalled. Global power balance has been analysed. These results confirm the enhanced radiation capacity of the ergodic divertor. (author)

  2. Generic singular continuous spectrum for ergodic Schr\\"odinger operators

    OpenAIRE

    Avila, Artur; Damanik, David

    2004-01-01

    We consider Schr\\"odinger operators with ergodic potential $V_\\omega(n)=f(T^n(\\omega))$, $n \\in \\Z$, $\\omega \\in \\Omega$, where $T:\\Omega \\to \\Omega$ is a non-periodic homeomorphism. We show that for generic $f \\in C(\\Omega)$, the spectrum has no absolutely continuous component. The proof is based on approximation by discontinuous potentials which can be treated via Kotani Theory.

  3. Ergodicity and slow diffusion in a supercooled liquid

    OpenAIRE

    Bidhoodi, Neeta; Das, Shankar P.

    2015-01-01

    A model for the slow dynamics of the supercooled liquid is formulated in terms of the standard equations of fluctuating nonlinear hydrodynamics (FNH) with the inclusion of an extra diffusive mode for the collective density fluctuations. If the compressible nature of the liquid is completely ignored, this diffusive mode sets the longest relaxation times in the supercooled state and smooths off a possible sharp ergodicity-nonergodicity (ENE) transition predicted in a mode coupling theory. The s...

  4. Ergodicity of the LLR method for the Density of States

    Directory of Open Access Journals (Sweden)

    Cossu Guido

    2018-01-01

    Full Text Available The LLR method is a novel algorithm that enables us to evaluate the density of states in lattice gauge theory. We present our study of the ergodicity properties of the LLR algorithm for the model of Yang Mills SU(3. We show that the use of the replica exchange method alleviates significantly the topological freeze-out that severely affects other algorithms.

  5. Ergodic time-reversible chaos for Gibbs' canonical oscillator

    International Nuclear Information System (INIS)

    Hoover, William Graham; Sprott, Julien Clinton; Patra, Puneet Kumar

    2015-01-01

    Nosé's pioneering 1984 work inspired a variety of time-reversible deterministic thermostats. Though several groups have developed successful doubly-thermostated models, single-thermostat models have failed to generate Gibbs' canonical distribution for the one-dimensional harmonic oscillator. A 2001 doubly-thermostated model, claimed to be ergodic, has a singly-thermostated version. Though neither of these models is ergodic this work has suggested a successful route toward singly-thermostated ergodicity. We illustrate both ergodicity and its lack for these models using phase-space cross sections and Lyapunov instability as diagnostic tools. - Highlights: • We develop cross-section and Lyapunov methods for diagnosing ergodicity. • We apply these methods to several thermostatted-oscillator problems. • We demonstrate the nonergodicity of previous work. • We find a novel family of ergodic thermostatted-oscillator problems.

  6. The Human - Nature Relationship i n t he Context o f Theo - Centric Environmental Ethics

    Directory of Open Access Journals (Sweden)

    Gülşen YAYLI

    2015-07-01

    Full Text Available The environmental problems are one of the issues that intensively occupy the agenda of humankind. This fact mainly derives from the ambiguity of the s pan and the content of the issue. The concept of environmental problems can not be confined to th e soil, air and water pollution for the reason that it covers a scope wider than a classical pollution issues. Initially the form of the relations hip between h uman and nature has been relying on the “consumption at the level of content” which stands for a level that is enough to sustain the living. The perception of the nature used to be described with the metaphor of mother while natural environment was defined as the “mother earth”. However subsequent to natural environment definition of the Cartesian philosophy with its approach to the human nature relationship, the core metaphor to describe the natural environment has changed from the metaphor of “mother” to the “slave” which should serve by any means. The human - nature relationship within the context of ethics, both the parties an d their respective statues bear an importance. In terms of ethics of human - nature relationship, it is possible to mention three main approaches. First one is the anthropo - centric approach. Within the scope of historical process, human - nature relationship is addressed according to anthropo - centric ethics comprehension so human has remained at the center of discussion. Following the change of the perception regarding the issue of environment, new approaches have emerged that give emphasis not only on human beings but also others; on li ving and non - living beings with in the eco - system. In principle, this represents a departure from an anthropo - centric ethics to a new ethic approach which fall s into two categories, bio centric and eco - centric. The theo - centric ethics should also be included to these ethics approaches that are shaped within the sphere of positive sciences. The Abrahamic

  7. Edge plasma control: Particle channeling in Tore Supra pump limiter and ergodic divertor

    International Nuclear Information System (INIS)

    Ghendrih, P.; Samain, A.; Grosman, A.; Capes, H.; Morera, J.P.

    1989-01-01

    Improved pumping efficiency can be achieved on Tore Supra by channeling process for particles, i.e. channeling of neutrals in the throat of pump limiters and channeling of plasma towards neutralizer plates in the ergodic divertor. The plugging length for the pump limiter throat is computed and numerical evidence of plasma flux channeling between the conductor bars of the ergodic divertor is presented. The effect of the Tore Supra ergodic divertor on edge plasma state and edge plasma transport is discussed. (orig.)

  8. Topology, ergodic theory, real algebraic geometry Rokhlin's memorial

    CERN Document Server

    Turaev, V

    2001-01-01

    This book is dedicated to the memory of the outstanding Russian mathematician, V. A. Rokhlin (1919-1984). It is a collection of research papers written by his former students and followers, who are now experts in their fields. The topics in this volume include topology (the Morse-Novikov theory, spin bordisms in dimension 6, and skein modules of links), real algebraic geometry (real algebraic curves, plane algebraic surfaces, algebraic links, and complex orientations), dynamics (ergodicity, amenability, and random bundle transformations), geometry of Riemannian manifolds, theory of Teichmüller

  9. Asymptotic Ergodic Capacity Analysis of Composite Lognormal Shadowed Channels

    KAUST Repository

    Ansari, Imran Shafique

    2015-05-01

    Capacity analysis of composite lognormal (LN) shadowed links, such as Rician-LN, Gamma-LN, and Weibull-LN, is addressed in this work. More specifically, an exact closed-form expression for the moments of the end-to-end signal-to-noise ratio (SNR) of a single composite link transmission system is presented in terms of well- known elementary functions. Capitalizing on these new moments expressions, we present asymptotically tight lower bounds for the ergodic capacity at high SNR. All the presented results are verified via computer-based Monte-Carlo simulations. © 2015 IEEE.

  10. Efficient estimation for ergodic diffusions sampled at high frequency

    DEFF Research Database (Denmark)

    Sørensen, Michael

    A general theory of efficient estimation for ergodic diffusions sampled at high fre- quency is presented. High frequency sampling is now possible in many applications, in particular in finance. The theory is formulated in term of approximate martingale estimating functions and covers a large class...... of parameters in the drift coefficient, and for efficiency. The conditions turn out to be equal to those implying small Δ-optimality in the sense of Jacobsen and thus gives an interpretation of this concept in terms of classical sta- tistical concepts. Optimal martingale estimating functions in the sense...

  11. A role for a Brachistochrone in the broken ergodicity scenario

    Science.gov (United States)

    Appignanesi, Gustavo A.

    2000-02-01

    We show that the time evolution of ergodic decomposition is outlined by a variational principle for a rather universal class of complex systems with a quasicontinuous spectrum of intrinsic relaxation timescales. In turn, this variational approach enables us to single out a logarithmic scaling law for the barriers on the hierarchical level. Such a logarithmic dependence has already been shown to hold valid for certain complex systems. Moreover, it represents a key factor to explain the experimentally ubiquitous Debye-Kohlrausch relaxation law and plays a central role on different theoretical model descriptions within this field.

  12. Equilibrium states and the ergodic theory of Anosov diffeomorphisms

    CERN Document Server

    2008-01-01

    For this printing of R. Bowen's book, J.-R. Chazottes has retyped it in TeX for easier reading, thereby correcting typos and bibliographic details. From the Preface by D. Ruelle: "Rufus Bowen has left us a masterpiece of mathematical exposition... Here a number of results which were new at the time are presented in such a clear and lucid style that Bowen's monograph immediately became a classic. More than thirty years later, many new results have been proved in this area, but the volume is as useful as ever because it remains the best introduction to the basics of the ergodic theory of hyperbolic systems."

  13. Ergodicity breaking in frustrated disordered systems: replicas in mean-field spin-glass models

    Czech Academy of Sciences Publication Activity Database

    Janiš, Václav; Kauch, Anna; Klíč, Antonín

    2015-01-01

    Roč. 88, č. 3 (2015), s. 245-263 ISSN 0141-1594 Institutional support: RVO:68378271 Keywords : ergodicity and thermodynamic homogeneity * real replicas * ergodicity and replica-symmetry breaking * asymptotic solution Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.858, year: 2015

  14. Ergodic theory, interpretations of probability and the foundations of statistical mechanics

    NARCIS (Netherlands)

    van Lith, J.H.

    2001-01-01

    The traditional use of ergodic theory in the foundations of equilibrium statistical mechanics is that it provides a link between thermodynamic observables and microcanonical probabilities. First of all, the ergodic theorem demonstrates the equality of microcanonical phase averages and infinite time

  15. Fluctuation, stationarity, and ergodic properties of random-matrix ensembles

    International Nuclear Information System (INIS)

    Pandey, A.

    1979-01-01

    The properties of random-matrix ensembles and the application of such ensembles to energy-level fluctuations and strength fluctuations are discussed. The two-point correlation function for complex spectra described by the three standard Gaussian ensembles is calculated, and its essential simplicity, displayed by an elementary procedure that derives from the dominance of binary correlations. The resultant function is exact for the unitary case and a very good approximation to the orthogonal and symplectic cases. The same procedure yields the spectrum for a Gaussian orthogonal ensemble (GOE) deformed by a pairing interaction. Several extensions are given and relationships to other problems of current interest are discussed. The standard fluctuation measures are rederived for the GOE, and their extensions to the unitary and symplectic cases are given. The measures are shown to derive, for the most part, from the two-point function, and new relationships between them are established, answering some long-standing questions. Some comparisons with experimental values are also made. All the cluster functions, and therefore the fluctuation measures, are shown to be stationary and strongly ergodic, thus justifying the use of random matrices for individual spectra. Strength fluctuations in the orthogonal ensemble are also considered. The Porter-Thomas distribution in its various forms is rederived and its ergodicity is established

  16. Ergodicity, hidden bias and the growth rate gain

    Science.gov (United States)

    Rochman, Nash D.; Popescu, Dan M.; Sun, Sean X.

    2018-05-01

    Many single-cell observables are highly heterogeneous. A part of this heterogeneity stems from age-related phenomena: the fact that there is a nonuniform distribution of cells with different ages. This has led to a renewed interest in analytic methodologies including use of the ‘von Foerster equation’ for predicting population growth and cell age distributions. Here we discuss how some of the most popular implementations of this machinery assume a strong condition on the ergodicity of the cell cycle duration ensemble. We show that one common definition for the term ergodicity, ‘a single individual observed over many generations recapitulates the behavior of the entire ensemble’ is implied by the other, ‘the probability of observing any state is conserved across time and over all individuals’ in an ensemble with a fixed number of individuals but that this is not true when the ensemble is growing. We further explore the impact of generational correlations between cell cycle durations on the population growth rate. Finally, we explore the ‘growth rate gain’—the phenomenon that variations in the cell cycle duration leads to an improved population-level growth rate—in this context. We highlight that, fundamentally, this effect is due to asymmetric division.

  17. Identifiability for the pointwise source detection in Fisher’s reaction–diffusion equation

    International Nuclear Information System (INIS)

    Belgacem, Faker Ben

    2012-01-01

    We are interested in the detection of a pointwise source in a class of semi-linear advection–diffusion–reaction equations of Fisher type. The source is determined by its location, which may be steady or unsteady, and its time-dependent intensity. Observations recorded at a couple of points are the available data. One observing station is located upstream of the source and the other downstream. This is a severely ill-posed nonlinear inverse problem. In this paper, we pursue an identifiability result. The process we follow has been developed earlier for the linear model and may be sharpened to operate for the semi-linear equation. It is based on the uniqueness for a parabolic (semi-linear) sideways problem, which is obtained by a suitable unique continuation theorem. We state a maximum principle that turns out to be necessary for our proof. The identifiability is finally obtained for a stationary or a moving source. Many applications may be found in biology, chemical physiology or environmental science. The problem we deal with is the detection of pointwise organic pollution sources in rivers and channels. The basic equation to consider is the one-dimensional biochemical oxygen demand equation, with a nonlinear power growth inhibitor and/or the Michaelis–Menten reaction coefficient. (paper)

  18. Converting point-wise nuclear cross sections to pole representation using regularized vector fitting

    Science.gov (United States)

    Peng, Xingjie; Ducru, Pablo; Liu, Shichang; Forget, Benoit; Liang, Jingang; Smith, Kord

    2018-03-01

    Direct Doppler broadening of nuclear cross sections in Monte Carlo codes has been widely sought for coupled reactor simulations. One recent approach proposed analytical broadening using a pole representation of the commonly used resonance models and the introduction of a local windowing scheme to improve performance (Hwang, 1987; Forget et al., 2014; Josey et al., 2015, 2016). This pole representation has been achieved in the past by converting resonance parameters in the evaluation nuclear data library into poles and residues. However, cross sections of some isotopes are only provided as point-wise data in ENDF/B-VII.1 library. To convert these isotopes to pole representation, a recent approach has been proposed using the relaxed vector fitting (RVF) algorithm (Gustavsen and Semlyen, 1999; Gustavsen, 2006; Liu et al., 2018). This approach however needs to specify ahead of time the number of poles. This article addresses this issue by adding a poles and residues filtering step to the RVF procedure. This regularized VF (ReV-Fit) algorithm is shown to efficiently converge the poles close to the physical ones, eliminating most of the superfluous poles, and thus enabling the conversion of point-wise nuclear cross sections.

  19. Identifiability for the pointwise source detection in Fisher’s reaction-diffusion equation

    Science.gov (United States)

    Ben Belgacem, Faker

    2012-06-01

    We are interested in the detection of a pointwise source in a class of semi-linear advection-diffusion-reaction equations of Fisher type. The source is determined by its location, which may be steady or unsteady, and its time-dependent intensity. Observations recorded at a couple of points are the available data. One observing station is located upstream of the source and the other downstream. This is a severely ill-posed nonlinear inverse problem. In this paper, we pursue an identifiability result. The process we follow has been developed earlier for the linear model and may be sharpened to operate for the semi-linear equation. It is based on the uniqueness for a parabolic (semi-linear) sideways problem, which is obtained by a suitable unique continuation theorem. We state a maximum principle that turns out to be necessary for our proof. The identifiability is finally obtained for a stationary or a moving source. Many applications may be found in biology, chemical physiology or environmental science. The problem we deal with is the detection of pointwise organic pollution sources in rivers and channels. The basic equation to consider is the one-dimensional biochemical oxygen demand equation, with a nonlinear power growth inhibitor and/or the Michaelis-Menten reaction coefficient.

  20. Steun, weerklank en vriendschap. Over sociaal kapitaal en de breuk tussen Piet Mondriaan en Theo van Doesburg

    Directory of Open Access Journals (Sweden)

    Alex Rutten

    2012-12-01

    Full Text Available An analysis of the behavior and position-taking of actors in the literary or artistic field should not focus merely on poetics and profit-maximizing strategies aimed at the accumulation of symbolic capital. At least as important is the subjective experience of social capital that these actors have. This includes values attached to respect, mutual understanding, friendship and support. To demonstrate the importance of these subjective aspects of social capital, I will argue that relational problems were the main cause for the break between De Stijl members Piet Mondriaan and Theo van Doesburg, rather than conflicting ideas about aesthetic matters.

  1. The Non-Ergodic Nature of Internal Conversion

    DEFF Research Database (Denmark)

    Kuhlman, Thomas Scheby

    The absorption of light by molecules can induce ultrafast dynamics of coupled electronic and nuclear vibrational motion. The ultrafast nature in many cases rests on the importance of several potential energy surfaces in guiding the nuclear dynamics – a concept of central importance in many aspects...... of chemical reaction dynamics. In this thesis, we focus on the non-ergodic nature of internal conversion, i.e. the concept that the nuclear dynamics only sample a reduced phase space potentially resulting in localization of the dynamics in real space. In essence, this is a consequence of vibrational energy...... redistribution simply not being able to compete with the rate of internal conversion. The work employ the experimental methods of time-resolved mass spectrometry and photoelectron spectroscopy supplemented by electronic structure calculations and quantum dynamics simulations on seven cycloketones, three...

  2. Asymptotic behaviour of time averages for non-ergodic Gaussian processes

    Science.gov (United States)

    Ślęzak, Jakub

    2017-08-01

    In this work, we study the behaviour of time-averages for stationary (non-ageing), but ergodicity-breaking Gaussian processes using their representation in Fourier space. We provide explicit formulae for various time-averaged quantities, such as mean square displacement, density, and analyse the behaviour of time-averaged characteristic function, which gives insight into rich memory structure of the studied processes. Moreover, we show applications of the ergodic criteria in Fourier space, determining the ergodicity of the generalised Langevin equation's solutions.

  3. Fatou type weighted pointwise convergence of nonlinear singular integral operators Depending on two parameters

    Directory of Open Access Journals (Sweden)

    Uysal Gumrah

    2016-01-01

    Full Text Available In this paper we present some theorems concerning existence and Fatou type weighted pointwise convergence of nonlinear singular integral operators of the form: (Tλf(x=∫RKλ(t−x; f(tdt, x∈R, λ∈Λ$({T_\\lambda }f(x = \\int\\limits_R {{K_\\lambda }} (t - x;{\\rm{ }}f(tdt,{\\rm{ x}} \\in R,{\\rm{ }}\\lambda \\in \\Lambda $ where Λ ≠ ∅ is a set of non-negative indices, at a common generalized Lebesgue point of the functions f ∈ L1,ϕ (R and positive weight function φ. Here, L1,ϕ (R is the space of all measurable functions for which |fϕ|$\\left| {{f \\over \\phi }} \\right|$ is integrable on R.

  4. Pointwise second-order necessary optimality conditions and second-order sensitivity relations in optimal control

    Science.gov (United States)

    Frankowska, Hélène; Hoehener, Daniel

    2017-06-01

    This paper is devoted to pointwise second-order necessary optimality conditions for the Mayer problem arising in optimal control theory. We first show that with every optimal trajectory it is possible to associate a solution p (ṡ) of the adjoint system (as in the Pontryagin maximum principle) and a matrix solution W (ṡ) of an adjoint matrix differential equation that satisfy a second-order transversality condition and a second-order maximality condition. These conditions seem to be a natural second-order extension of the maximum principle. We then prove a Jacobson like necessary optimality condition for general control systems and measurable optimal controls that may be only ;partially singular; and may take values on the boundary of control constraints. Finally we investigate the second-order sensitivity relations along optimal trajectories involving both p (ṡ) and W (ṡ).

  5. A fast pointwise strategy for anisotropic wave-mode separation in TI media

    KAUST Repository

    Liu, Qiancheng

    2017-08-17

    The multi-component wavefield contains both compressional and shear waves. Separating wave-modes has many applications in seismic workflows. Conventionally, anisotropic wave-mode separation is implemented by either directly filtering in the wavenumber domain or nonstationary filtering in the space domain, which are computationally expensive. These methods could be categorized into the pseudo-derivative family and only work well within Finite Difference (FD) methods. In this paper, we establish a relationship between group-velocity direction and polarity direction and propose a method, which could go beyond modeling by FD. In particular, we are interested in performing wave-mode separation in a Spectral Element Method (SEM), which is widely used for seismic wave propagation on various scales. The separation is implemented pointwise, independent of its neighbor points, suitable for running in parallel. Moreover, no correction for amplitude and phase changes caused by the derivative operator is required. We have verified our scheme using numerical examples.

  6. OPTIMAL CONTROL OF A NONLINEAR COUPLED ELECTROMAGNETIC INDUCTION HEATING SYSTEM WITH POINTWISE STATE CONSTRAINTS

    Directory of Open Access Journals (Sweden)

    Irwin Yousept

    2010-07-01

    Full Text Available An optimal control problem arising in the context of 3D electromagnetic induction heating is investigated. The state equation is given by a quasilinear stationary heat equation coupled with a semilinear time harmonic eddy current equation. The temperature-dependent electrical conductivity and the presence of pointwise inequality state-constraints represent the main challenge of the paper. In the first part of the paper, the existence and regularity of the state are addressed. The second part of the paper deals with the analysis of the corresponding linearized equation. Some suffcient conditions are presented which guarantee thesolvability of the linearized system. The final part of the paper is concerned with the optimal control. The aim of the optimization is to find the optimal voltage such that a desired temperature can be achieved optimally. The corresponding first-order necessary optimality condition is presented.

  7. De miskenning van Theo van Doesburg; zijn bijdrage tot de ontwikkeling van de konkrete poëzie

    Directory of Open Access Journals (Sweden)

    J. van der Elst

    1987-05-01

    Full Text Available More literary critics outside Belgium and the Netherlands have written about Theo van Doesburg than from inside these countries. The first important monograph on him appeared in English - Theo van Doesburg - Propagandist and Practitioner of the Avant-Garde, 1909-1923, by Hannah Hedrick. Van Doesburg’s poetry developed in the direction of concrete poetry - the type of poetry in which the spatial, acoustic and visual characteristics of language are maximally utilized towards the creation of the poem. Word as sound and as image is foregrounded in concrete poetry, while the imaging of persons and subjective experience is eliminated as far as possible. The anecdotal or the epic component of the concrete poem is minimal and the language of this sort of poem has been reduced to the minimum. In the spirit of the theory of concrete poetry Van Doesburg advocates the liberation of art from all the commitments imposed upon it. That with which Van Doesburg began was continued by other poets, especially in Germanic literature by poets of the so-called neo-realism.

  8. Measuring global oil trade dependencies: An application of the point-wise mutual information method

    International Nuclear Information System (INIS)

    Kharrazi, Ali; Fath, Brian D.

    2016-01-01

    Oil trade is one of the most vital networks in the global economy. In this paper, we analyze the 1998–2012 oil trade networks using the point-wise mutual information (PMI) method and determine the pairwise trade preferences and dependencies. Using examples of the USA's trade partners, this research demonstrates the usefulness of the PMI method as an additional methodological tool to evaluate the outcomes from countries' decisions to engage in preferred trading partners. A positive PMI value indicates trade preference where trade is larger than would be expected. For example, in 2012 the USA imported 2,548.7 kbpd despite an expected 358.5 kbpd of oil from Canada. Conversely, a negative PMI value indicates trade dis-preference where the amount of trade is smaller than what would be expected. For example, the 15-year average of annual PMI between Saudi Arabia and the U.S.A. is −0.130 and between Russia and the USA −1.596. We reflect the three primary reasons of discrepancies between actual and neutral model trade can be related to position, price, and politics. The PMI can quantify the political success or failure of trade preferences and can more accurately account temporal variation of interdependencies. - Highlights: • We analyzed global oil trade networks using the point-wise mutual information method. • We identified position, price, & politics as drivers of oil trade preference. • The PMI method is useful in research on complex trade networks and dependency theory. • A time-series analysis of PMI can track dependencies & evaluate policy decisions.

  9. What Then Happens When Interaction is Not Possible: The Virtuosic Interpretation of Ergodic Artefacts

    Directory of Open Access Journals (Sweden)

    Miguel Carvalhais

    2015-11-01

    Full Text Available Procedural systems allow unique modes of authorship and singular aesthetic experiences. As creators and users of these systems, we need to be aware that their aesthetic potential is not solely defined by interaction but that interpretation, and the capacity to understand and simulate the processes taking place within these artefacts is highly significant. This paper argues that although direct interaction is usually the most discernible component in the relationship between ergodic artefacts and their users, ergodicity does not necessarily imply interaction. Non-interactive procedural artefacts may allow the development of ergodic experiences through interpretation, and the probing of the system by its reader through simulations. We try to set the grounds for designing towards virtuosic interpretation, an activity that we may describe as the ergodic experience developed by means of mental simulation through the development of theories of systems.

  10. Rates of convergence and asymptotic normality of curve estimators for ergodic diffusion processes

    NARCIS (Netherlands)

    J.H. van Zanten (Harry)

    2000-01-01

    textabstractFor ergodic diffusion processes, we study kernel-type estimators for the invariant density, its derivatives and the drift function. We determine rates of convergence and find the joint asymptotic distribution of the estimators at different points.

  11. Upper and lower bounds for the ergodic capacity of MIMO Jacobi fading channels.

    Science.gov (United States)

    Nafkha, Amor; Bonnefoi, Rémi

    2017-05-29

    In multi-(core/mode) optical fiber communication, the transmission channel can be modeled as a complex sub-matrix of the Haar-distributed unitary matrix (complex Jacobi unitary ensemble). In this letter, we present new analytical expressions of the upper and lower bounds for the ergodic capacity of multiple-input multiple-output Jacobi-fading channels. Recent results on the determinant of the Jacobi unitary ensemble are employed to derive a tight lower bound on the ergodic capacity. We use Jensen's inequality to provide an analytical closed-form upper bound to the ergodic capacity at any signal-to-noise ratio (SNR). Closed-form expressions of the ergodic capacity, at low and high SNR regimes, are also derived. Simulation results are presented to validate the accuracy of the derived expressions.

  12. Let the Game Begin: Ergodic as an Approach for Video Game Translation

    OpenAIRE

    SF. Lukfianka Sanjaya Purnama; SF. Luthfie Arguby Purnomo; Dyah Nugrahani

    2016-01-01

    This paper attempts to propose ergodic as an approach for video game translation. The word approach here refers to an approach for translation products and to an approach for the translation process. The steps to formulate ergodic as an approach are first, Aarseth’sergodic literature is reviewed to elicit a basis for comprehension toward its relationship with video games and video game translation Secondly, taking the translation of Electronic Arts’Need for Speed: Own the City, Midway’s Morta...

  13. Ergodicity and Parameter Estimates for Infinite-Dimensional Fractional Ornstein-Uhlenbeck Process

    International Nuclear Information System (INIS)

    Maslowski, Bohdan; Pospisil, Jan

    2008-01-01

    Existence and ergodicity of a strictly stationary solution for linear stochastic evolution equations driven by cylindrical fractional Brownian motion are proved. Ergodic behavior of non-stationary infinite-dimensional fractional Ornstein-Uhlenbeck processes is also studied. Based on these results, strong consistency of suitably defined families of parameter estimators is shown. The general results are applied to linear parabolic and hyperbolic equations perturbed by a fractional noise

  14. Role of the pump limiter throat-ergodic divertor effect on edge plasma

    International Nuclear Information System (INIS)

    Grosman, A.; Samain, A.; Ghendrih, P.; Capes, H.; Morera, J.P.

    1988-01-01

    A large part of the Tore Supra programme is devoted to plasma edge studies. Two types of such density control apparatus have been implemented, a set of pumps limiters and the ergodic divertor. The goal of the present paper is to investigate the effect of the pump limiter throat on pumping efficiency. We present also the possibilities of the ergodic divertor device to facilitate plasma pumping and power exhaust

  15. Fractional Feynman-Kac equation for weak ergodicity breaking.

    Science.gov (United States)

    Carmi, Shai; Barkai, Eli

    2011-12-01

    The continuous-time random walk (CTRW) is a model of anomalous subdiffusion in which particles are immobilized for random times between successive jumps. A power-law distribution of the waiting times, ψ(τ) ~ τ(-(1+α)), leads to subdiffusion (x(2) ~ t(α)) for 0 CTRW in a binding potential. We use our equations to study two specific time averages: the fraction of time spent by a particle in half-box, and the time average of the particle's position in a harmonic field. In both cases, we obtain the probability density function of the time averages for t → ∞ and the first two moments. Our results show that both the occupation fraction and the time-averaged position are random variables even for long times, except for α = 1, when they are identical to their ensemble averages. Using our fractional Feynman-Kac equation, we also study the dynamics leading to weak ergodicity breaking, namely the convergence of the fluctuations to their asymptotic values.

  16. Resampling-based multiple comparison procedure with application to point-wise testing with functional data.

    Science.gov (United States)

    Vsevolozhskaya, Olga A; Greenwood, Mark C; Powell, Scott L; Zaykin, Dmitri V

    2015-03-01

    In this paper we describe a coherent multiple testing procedure for correlated test statistics such as are encountered in functional linear models. The procedure makes use of two different p -value combination methods: the Fisher combination method and the Šidák correction-based method. P -values for Fisher's and Šidák's test statistics are estimated through resampling to cope with the correlated tests. Building upon these two existing combination methods, we propose the smallest p -value as a new test statistic for each hypothesis. The closure principle is incorporated along with the new test statistic to obtain the overall p -value and appropriately adjust the individual p -values. Furthermore, a shortcut version for the proposed procedure is detailed, so that individual adjustments can be obtained even for a large number of tests. The motivation for developing the procedure comes from a problem of point-wise inference with smooth functional data where tests at neighboring points are related. A simulation study verifies that the methodology performs well in this setting. We illustrate the proposed method with data from a study on the aerial detection of the spectral effect of below ground carbon dioxide leakage on vegetation stress via spectral responses.

  17. Stress-induced alterations of left-right electrodermal activity coupling indexed by pointwise transinformation.

    Science.gov (United States)

    Světlák, M; Bob, P; Roman, R; Ježek, S; Damborská, A; Chládek, J; Shaw, D J; Kukleta, M

    2013-01-01

    In this study, we tested the hypothesis that experimental stress induces a specific change of left-right electrodermal activity (EDA) coupling pattern, as indexed by pointwise transinformation (PTI). Further, we hypothesized that this change is associated with scores on psychometric measures of the chronic stress-related psychopathology. Ninety-nine university students underwent bilateral measurement of EDA during rest and stress-inducing Stroop test and completed a battery of self-report measures of chronic stress-related psychopathology. A significant decrease in the mean PTI value was the prevalent response to the stress conditions. No association between chronic stress and PTI was found. Raw scores of psychometric measures of stress-related psychopathology had no effect on either the resting levels of PTI or the amount of stress-induced PTI change. In summary, acute stress alters the level of coupling pattern of cortico-autonomic influences on the left and right sympathetic pathways to the palmar sweat glands. Different results obtained using the PTI, EDA laterality coefficient, and skin conductance level also show that the PTI algorithm represents a new analytical approach to EDA asymmetry description.

  18. Point-wise and whole-field laser speckle intensity fluctuation measurements applied to botanical specimens

    Science.gov (United States)

    Zhao, Yang; Wang, Junlan; Wu, Xiaoping; Williams, Fred W.; Schmidt, Richard J.

    1997-12-01

    Based on multi-scattering speckle theory, the speckle fields generated by plant specimens irradiated by laser light have been studied using a pointwise method. In addition, a whole-field method has been developed with which entire botanical specimens may be studied. Results are reported from measurements made on tomato and apple fruits, orange peel, leaves of tobacco seedlings, leaves of shihu seedlings (a Chinese medicinal herb), soy-bean sprouts, and leaves from an unidentified trailing houseplant. Although differences where observed in the temporal fluctuations of speckles that could be ascribed to differences in age and vitality, the growing tip of the bean sprout and the shihu seedling both generated virtually stationary speckles such as were observed from boiled orange peel and from localised heat-damaged regions on apple fruit. Our results suggest that both the identity of the botanical specimen and the site at which measurements are taken are likely to critically affect the observation or otherwise of temporal fluctuations of laser speckles.

  19. Ergodic theory and negative curvature CIRM Jean-Morlet Chair, Fall 2013

    CERN Document Server

    2017-01-01

    Focussing on the mathematics related to the recent proof of ergodicity of the (Weil–Petersson) geodesic flow on a nonpositively curved space whose points are negatively curved metrics on surfaces, this book provides a broad introduction to an important current area of research. It offers original textbook-level material suitable for introductory or advanced courses as well as deep insights into the state of the art of the field, making it useful as a reference and for self-study.  The first chapters introduce hyperbolic dynamics, ergodic theory and geodesic and horocycle flows, and include an English translation of Hadamard's original proof of the Stable-Manifold Theorem. An outline of the strategy, motivation and context behind the ergodicity proof is followed by a careful exposition of it (using the Hopf argument) and of the pertinent context of Teichmüller theory. Finally, some complementary lectures describe the deep connections between geodesic flows in negative curvature and Diophantine approximatio...

  20. On the Ergodic Capacity of Dual-Branch Correlated Log-Normal Fading Channels with Applications

    KAUST Repository

    Al-Quwaiee, Hessa

    2015-05-01

    Closed-form expressions of the ergodic capacity of independent or correlated diversity branches over Log-Normal fading channels are not available in the literature. Thus, it is become of an interest to investigate the behavior of such metric at high signal-to-noise (SNR). In this work, we propose simple closed-form asymptotic expressions of the ergodic capacity of dual-branch correlated Log- Normal corresponding to selection combining, and switch-and-stay combining. Furthermore, we capitalize on these new results to find new asymptotic ergodic capacity of correlated dual- branch free-space optical communication system under the impact of pointing error with both heterodyne and intensity modulation/direct detection. © 2015 IEEE.

  1. A class of regular invariants as asymptotical limits or ergodic means

    International Nuclear Information System (INIS)

    Courbage, M.

    1977-01-01

    The asymptotic or ergodic behavior of a class of initial states for quantum statistical systems where the collision operator, introduced by Prigogine and coworkers, is non-vanishing is studied. In this case, they distinguish two particular classes of invariants, called respectively regular and collisionnal invariants, among the invariants of the motion. A class of initial states which tend to those invariants asymptotically or in the ergodic mean is caracterized using the destruction operator and some spectral properties of the representation in the case of systems whose hamiltonians have an absolutely continuous part in their spectrum. Furthermore, collisional invariants which can be obtained as ergodic means of some equivalence class of one initial state are characterized in terms of the GAMMA + Friedrichs operator. Uniqueness of that initial state is lost when the asymptotic collision operator is non-vanishing [fr

  2. Pointwise mutual information quantifies intratumor heterogeneity in tissue sections labeled with multiple fluorescent biomarkers

    Directory of Open Access Journals (Sweden)

    Daniel M Spagnolo

    2016-01-01

    Full Text Available Background: Measures of spatial intratumor heterogeneity are potentially important diagnostic biomarkers for cancer progression, proliferation, and response to therapy. Spatial relationships among cells including cancer and stromal cells in the tumor microenvironment (TME are key contributors to heterogeneity. Methods: We demonstrate how to quantify spatial heterogeneity from immunofluorescence pathology samples, using a set of 3 basic breast cancer biomarkers as a test case. We learn a set of dominant biomarker intensity patterns and map the spatial distribution of the biomarker patterns with a network. We then describe the pairwise association statistics for each pattern within the network using pointwise mutual information (PMI and visually represent heterogeneity with a two-dimensional map. Results: We found a salient set of 8 biomarker patterns to describe cellular phenotypes from a tissue microarray cohort containing 4 different breast cancer subtypes. After computing PMI for each pair of biomarker patterns in each patient and tumor replicate, we visualize the interactions that contribute to the resulting association statistics. Then, we demonstrate the potential for using PMI as a diagnostic biomarker, by comparing PMI maps and heterogeneity scores from patients across the 4 different cancer subtypes. Estrogen receptor positive invasive lobular carcinoma patient, AL13-6, exhibited the highest heterogeneity score among those tested, while estrogen receptor negative invasive ductal carcinoma patient, AL13-14, exhibited the lowest heterogeneity score. Conclusions: This paper presents an approach for describing intratumor heterogeneity, in a quantitative fashion (via PMI, which departs from the purely qualitative approaches currently used in the clinic. PMI is generalizable to highly multiplexed/hyperplexed immunofluorescence images, as well as spatial data from complementary in situ methods including FISSEQ and CyTOF, sampling many different

  3. Can future systemic financial risks be quantified?: ergodic vs nonergodic stochastic processes

    Directory of Open Access Journals (Sweden)

    Paul Davidson

    2009-12-01

    Full Text Available Different axioms underlie efficient market theory and Keynes's liquidity preference theory. Efficient market theory assumes the ergodic axiom. Consequently, today's decision makers can calculate with actuarial precision the future value of all possible outcomes resulting from today's decisions. Since in an efficient market world decision makers "know" their intertemporal budget constraints, decision makers never default on a loan, i.e., systemic defaults, insolvencies, and bankruptcies are impossible. Keynes liquidity preference theory rejects the ergodic axiom. The future is ontologically uncertain. Accordingly systemic defaults and insolvencies can occur but can never be predicted in advance.

  4. On Modelling Long Term Stock Returns with Ergodic Diffusion Processes: Arbitrage and Arbitrage-Free Specifications

    Directory of Open Access Journals (Sweden)

    Bernard Wong

    2009-01-01

    martingale component is based on an ergodic diffusion with a specified stationary distribution. These models are particularly useful for long horizon asset-liability management as they allow the modelling of long term stock returns with heavy tail ergodic diffusions, with tractable, time homogeneous dynamics, and which moreover admit a complete financial market, leading to unique pricing and hedging strategies. Unfortunately the standard specifications of these models in literature admit arbitrage opportunities. We investigate in detail the features of the existing model specifications which create these arbitrage opportunities and consequently construct a modification that is arbitrage free.

  5. Self-averaging and ergodicity of subdiffusion in quenched random media

    Science.gov (United States)

    Dentz, Marco; Russian, Anna; Gouze, Philippe

    2016-01-01

    We study the self-averaging properties and ergodicity of the mean square displacement m (t ) of particles diffusing in d dimensional quenched random environments which give rise to subdiffusive average motion. These properties are investigated in terms of the sample to sample fluctuations as measured by the variance of m (t ) . We find that m (t ) is not self-averaging for d 2 obeys a CTRW, which by itself displays weak ergodicity breaking. This paradox is resolved by the observation that the CTRW as an average model does not reflect the disorder sampling by random motion in a single medium realization.

  6. Food-induced changes in theophylline absorption from controlled-release formulations. Part I. Substantial increased and decreased absorption with Uniphyl tablets and Theo-Dur Sprinkle.

    Science.gov (United States)

    Karim, A; Burns, T; Wearley, L; Streicher, J; Palmer, M

    1985-07-01

    Food-induced changes in absorption from two controlled-release formulations of theophylline (Uniphyl tablets [Purdue Frederick Co.] and Theo-Dur Sprinkle [Key Pharmaceuticals, Inc.]) were studied in healthy male nonsmokers. Although the two forms exhibited a theophylline in vitro dissolution rate that was independent of changes in pH from 1 to 8, they showed substantial but opposite food-induced absorption changes. In a 12-subject, three-way, single-dose, randomized, crossover study the bioavailability of theophylline relative to immediate-release aminophylline tablets increased from 53% +/- 23% (means +/- SD) to 96% +/- 46% when Uniphyl (two 400 mg tablets) was taken under fasting and nonfasting (high fat content meal) conditions, respectively. On the other hand, in a separate six-subject, two-way, randomized, crossover study, food reduced the bioavailability of theophylline from Theo-Dur Sprinkle: Theophylline bioavailability in the nonfasting state was only 53% +/- 9% that in the fasting state.

  7. In vivo Anomalous Diffusion and Weak Ergodicity Breaking of Lipid Granules

    DEFF Research Database (Denmark)

    Jeon, J.-H.; Tejedor, V.; Burov, S.

    2011-01-01

    according to the laws of continuous time random walk theory. The associated violation of ergodicity leads to a characteristic turnover between two scaling regimes of the time averaged mean squared displacement. At longer times the granule motion is consistent with fractional Brownian motion....

  8. Ergodicity and parameter estimates for infinite-dimensional fractional Ornstein-Uhlenbeck process

    Czech Academy of Sciences Publication Activity Database

    Maslowski, Bohdan; Pospíšil, J.

    2008-01-01

    Roč. 57, č. 3 (2008), s. 401-429 ISSN 0095-4616 R&D Projects: GA ČR GA201/07/0237 Institutional research plan: CEZ:AV0Z10190503 Keywords : ergodicity * fractional OU process * parameter estimates Subject RIV: BA - General Mathematics Impact factor: 0.667, year: 2008

  9. Non-ergodic delocalized phase in Anderson model on Bethe lattice and regular graph

    Science.gov (United States)

    Kravtsov, V. E.; Altshuler, B. L.; Ioffe, L. B.

    2018-02-01

    We develop a novel analytical approach to the problem of single particle localization in infinite dimensional spaces such as Bethe lattice and random regular graph models. The key ingredient of the approach is the notion of the inverted order thermodynamic limit (IOTL) in which the coupling to the environment goes to zero before the system size goes to infinity. Using IOTL and Replica Symmetry Breaking (RSB) formalism we derive analytical expressions for the fractal dimension D1 that distinguishes between the extended ergodic, D1 = 1, and extended non-ergodic (multifractal), 0 graphs with the branching number K. We also employ RSB formalism to derive the analytical expression ln Styp-1 = - 〈 ln S 〉 ∼(Wc - W) - 1 for the typical imaginary part of self-energy Styp in the non-ergodic phase close to the Anderson transition in the conventional thermodynamic limit. We prove the existence of an extended non-ergodic phase in a broad range of disorder strength and energy and establish the phase diagrams of the models as a function of disorder and energy. The results of the analytical theory are compared with large-scale population dynamics and with the exact diagonalization of Anderson model on random regular graphs. We discuss the consequences of these results for the many body localization.

  10. Extinction and Ergodic Property of Stochastic SIS Epidemic Model with Nonlinear Incidence Rate

    Directory of Open Access Journals (Sweden)

    Qixing Han

    2013-01-01

    Full Text Available We investigate a stochastic SIS model with nonlinear incidence rate. We show that there exists a unique nonnegative solution to the system, and condition for the infectious individuals I(t to be extinct is given. Moreover, we prove that the system has ergodic property. Finally, computer simulations are carried out to verify our results.

  11. Ruin probability with claims modeled by a stationary ergodic stable process

    NARCIS (Netherlands)

    Mikosch, T; Samorodnitsky, G

    2000-01-01

    For a random walk with negative drift we study the exceedance probability (ruin probability) of a high threshold. The steps of this walk (claim sizes) constitute a stationary ergodic stable process. We study how ruin occurs in this situation and evaluate the asymptotic behavior of the ruin

  12. Let the Game Begin: Ergodic as an Approach for Video Game Translation

    Directory of Open Access Journals (Sweden)

    Sf. Lukfianka Sanjaya Purnama, Sf. Luthfie Arguby Purnomo, Dyah Nugrahani

    2017-01-01

    Full Text Available This paper attempts to propose ergodic as an approach for video game translation. The word approach here refers to an approach for translation products and to an approach for the translation process. The steps to formulate ergodic as an approach are first, Aarseth’sergodic literature is reviewed to elicit a basis for comprehension toward its relationship with video games and video game translation Secondly, taking the translation of Electronic Arts’Need for Speed: Own the City, Midway’s Mortal Kombat: Unchained, and Konami’s Metal Gear Solid, ergodic based approach for video game translation is formulated. The formulation signifies that ergodic, as an approach for video game translation, revolves around the treatment of video games as a cybertext from which scriptons, textons, and traversal functions as the configurative mechanism influence the selection of translation strategies and the transferability of variables and traversal function, game aesthetics, and ludus and narrative of the games. The challenges countered when treating video games as a cybertext are the necessities for the translators to convey anamorphosis, mechanical and narrative hidden meaning of the analyzed frame, to consider the textonomy of the games, and at the same time to concern on GILT (Globalization, Internationalization, Localization, and Translation.

  13. A Simple Proof of the Theorem Concerning Optimality in a One-Dimensional Ergodic Control Problem

    International Nuclear Information System (INIS)

    Fujita, Y.

    2000-01-01

    We give a simple proof of the theorem concerning optimality in a one-dimensional ergodic control problem. We characterize the optimal control in the class of all Markov controls. Our proof is probabilistic and does not need to solve the corresponding Bellman equation. This simplifies the proof

  14. Strong laws for generalized absolute Lorenz curves when data are stationary and ergodic sequences

    NARCIS (Netherlands)

    R. Helmers (Roelof); R. Zitikis

    2004-01-01

    textabstractWe consider generalized absolute Lorenz curves that include, as special cases, classical and generalized L - statistics as well as absolute or, in other words, generalized Lorenz curves. The curves are based on strictly stationary and ergodic sequences of random variables. Most of the

  15. arXiv Ergodicity of the LLR method for the Density of States

    CERN Document Server

    Cossu, Guido; Pellegrini, Roberto; Rago, Antonio

    2018-01-01

    The LLR method is a novel algorithm that enables us to evaluate the density of states in lattice gauge theory. We present our study of the ergodicity properties of the LLR algorithm for the model of Yang Mills SU(3). We show that the use of the replica exchange method alleviates significantly the topological freeze-out that severely affects other algorithms.

  16. Quantum Unique Ergodicity for Eisenstein Series on the Hilbert Modular Group over a Totally Real Field

    DEFF Research Database (Denmark)

    Truelsen, Jimi Lee

    W. Luo and P. Sarnak have proved quantum unique ergodicity for Eisenstein series on $PSL(2,Z) \\backslash H$. We extend their result to Eisenstein series on $PSL(2,O) \\backslash H^n$, where $O$ is the ring of integers in a totally real field of degree $n$ over $Q$ with narrow class number one, using...

  17. Electron heat diffusivity in radially-bounded ergodic region of toroidal plasma

    Science.gov (United States)

    Kanno, Ryutaro; Nunami, Masanori; Satake, Shinsuke; Matsuoka, Seikichi; Takamaru, Hisanori

    2018-01-01

    Drift-kinetic δ f simulations are performed to investigate effect of ergodic field lines caused by resonant magnetic perturbations (RMPs) on radial heat diffusivity of electrons in the edge region of toroidal plasma of collisionality ν_\\ast ∼ 0.1 . The following is assumed in the simulations. The ergodic region is bounded radially on both sides by closed magnetic surfaces. The pressure gradient remains nonzero in the ergodic region because of an incomplete flattening of the pressure profile, and the characteristic scale length of the pressure gradient is of larger order than the overlapping width of the neighbouring magnetic islands. It is found in the quasi-steady state of δ f that the electron heat diffusivity is of smaller order than the theoretical estimate derived by the Rechester–Rosenbluth model (Rechester and Rosenbluth 1978 Phys. Rev. Lett. 40 38). The radial heat conduction is dominated not only by parallel motions along the ergodic field lines, but also by trapped particle motions generated by the RMP field. The contribution of the trapped particles reduces the radial heat conduction enhanced by the parallel motions.

  18. A noncommutative mean ergodic theorem for partial W*-dynamical semigroups

    International Nuclear Information System (INIS)

    Ekhaguere, G.O.S.

    1992-12-01

    A noncommutative mean ergodic theorem for dynamical semigroups of maps on partial W*-algebras of linear operators from a pre-Hilbert space into its completion is proved. This generalizes a similar result of Watanabe for dynamical semigroups of maps on W*-algebras of operators. (author). 14 refs

  19. The Spatio-temporal Statistical Structure and Ergodic Behaviour of Scalar Turbulence Within a Rod Canopy

    Science.gov (United States)

    Ghannam, Khaled; Poggi, Davide; Porporato, Amilcare; Katul, Gabriel G.

    2015-12-01

    Connections between the spatial and temporal statistics of turbulent flow, and their possible convergence to ensemble statistics as assumed by the ergodic hypothesis, are explored for passive scalars within a rod canopy. While complete ergodicity is not expected to apply over all the spatial domain within such heterogeneous flows, the fact that canopy turbulence exhibits self-similar characteristics at a given depth within the canopy encourages a discussion on necessary conditions for an `operational' ergodicity framework. Flows between roughness elements such as within canopies exhibit features that distinguish them from their well-studied classical boundary-layer counterparts. These differences are commonly attributed to short-circuiting of the energy cascade and the prevalence of intermittent von Kármán vortex streets in the deeper layers of the canopy. Using laser-induced fluorescence measurements at two different depths within a rod canopy situated in a large flume, the spatio-temporal statistical properties and concomitant necessary conditions for ergodicity of passive scalar turbulence statistics are evaluated. First, the integral time and length scales are analyzed and their corresponding maximum values are used to guide the construction of an ensemble of independent realizations from repeated spatio-temporal concentration measurements. As a statistical analysis for an operational ergodicity check, a Kolmogorov-Smirnov test on the distributions of temporal and spatial concentration series against the ensemble was conducted. The outcome of this test reveals that ergodicity is reasonably valid over the entire domain except close to the rod elements where wake-induced inhomogeneities and damped turbulence prevail. The spatial concentration statistics within a grid-cell (square domain formed by four corner rods) appear to be less ergodic than their temporal counterparts, which is not surprising given the periodicity and persistence of von Kármán vortices in

  20. Loss of Ergodicity in the Transition from Annealed to Quenched Disorder in a Finite Kinetic Ising Model

    Science.gov (United States)

    Pigeard de Almeida Prado, Fernando; Schütz, Gunter M.

    2011-03-01

    We consider a kinetic Ising model which represents a generic agent-based model for various types of socio-economic systems. We study the case of a finite (and not necessarily large) number of agents N as well as the asymptotic case when the number of agents tends to infinity. The main ingredient are individual decision thresholds which are either fixed over time (corresponding to quenched disorder in the Ising model, leading to nonlinear deterministic dynamics which are generically non-ergodic) or which may change randomly over time (corresponding to annealed disorder, leading to ergodic dynamics). We address the question how increasing the strength of annealed disorder relative to quenched disorder drives the system from non-ergodic behavior to ergodicity. Mathematically rigorous analysis provides an explicit and detailed picture for arbitrary realizations of the quenched initial thresholds, revealing an intriguing "jumpy" transition from non-ergodicity with many absorbing sets to ergodicity. For large N we find a critical strength of annealed randomness, above which the system becomes asymptotically ergodic. Our theoretical results suggests how to drive a system from an undesired socio-economic equilibrium (e.g. high level of corruption) to a desirable one (low level of corruption).

  1. Exospheric and interplanetary hydrogen sensing from a translunar CubeSat platform by the Tomographic Hydrogen Emission Observatory (THEO)

    Science.gov (United States)

    Waldrop, L.; Sample, J. G.; Doe, R.; Noto, J.; Walsh, B.; Kamalabadi, F.; Mierkiewicz, E. J.; Kerr, R. B.; Immel, T. J.

    2015-12-01

    The evaporation of neutral hydrogen (H) atmospheres into interplanetary space is a near-ubiquitous process in the universe that can be strongly perturbed by charge exchange coupling with ambient ions, influencing atmospheric evolution as well as the dissipation of plasma energy. Space-based observation of solar ultraviolet (UV) radiation scattered by H atoms is a powerful means to infer the underlying exospheric density distribution and thus unravel the competing effects of thermal and non-thermal processes on H energization and escape. Numerous past and present NASA missions have obtained measurements of terrestrial H emission at 121.6 nm (Lyman alpha) from earth-orbiting satellite platforms. However, their separate targeting of either the optically thick emission in the lower exosphere or the optically thin emission in the outer exosphere, together with their lack of independent measurement of the interplanetary emission that constitutes a significant background contamination, renders such data insufficient to advance exospheric science beyond current understanding. Here, we describe a new nano-satellite mission concept for exospheric H investigation that overcomes these historical measurement limitations. The mission, known as the Tomographic Hydrogen Emission Observatory (THEO), is designed to provide 3-D photometric measurements of terrestrial H Lyman alpha emission from a highly autonomous, three-axis-stabilized, 6U CubeSat platform along a trans-lunar trajectory that is ideal for the unambiguous estimation of H density from the exobase to the magnetopause and beyond. In particular, we will describe the feasibility of meeting operational challenges associated with satellite navigation and communication at such large distances.

  2. Broad frequency band full field measurements for advanced applications: Point-wise comparisons between optical technologies

    Science.gov (United States)

    Zanarini, Alessandro

    2018-01-01

    The progress of optical systems gives nowadays at disposal on lightweight structures complex dynamic measurements and modal tests, each with its own advantages, drawbacks and preferred usage domains. It is thus more easy than before to obtain highly spatially defined vibration patterns for many applications in vibration engineering, testing and general product development. The potential of three completely different technologies is here benchmarked on a common test rig and advanced applications. SLDV, dynamic ESPI and hi-speed DIC are here first deployed in a complex and unique test on the estimation of FRFs with high spatial accuracy from a thin vibrating plate. The latter exhibits a broad band dynamics and high modal density in the common frequency domain where the techniques can find an operative intersection. A peculiar point-wise comparison is here addressed by means of discrete geometry transforms to put all the three technologies on trial at each physical point of the surface. Full field measurement technologies cannot estimate only displacement fields on a refined grid, but can exploit the spatial consistency of the results through neighbouring locations by means of numerical differentiation operators in the spatial domain to obtain rotational degrees of freedom and superficial dynamic strain distributions, with enhanced quality, compared to other technologies in literature. Approaching the task with the aid of superior quality receptance maps from the three different full field gears, this work calculates and compares rotational and dynamic strain FRFs. Dynamic stress FRFs can be modelled directly from the latter, by means of a constitutive model, avoiding the costly and time-consuming steps of building and tuning a numerical dynamic model of a flexible component or a structure in real life conditions. Once dynamic stress FRFs are obtained, spectral fatigue approaches can try to predict the life of a component in many excitation conditions. Different

  3. Divertor plasma modification by divertor biasing and edge ergodization in JFT-2M

    International Nuclear Information System (INIS)

    Shoji, T.; Nagashima, K.; Tamai, H.; Ohdachi, S.; Miura, Y.; Ohasa, K.; Maeda, H.; Ohyabu, N.; Leonard, A.W.; Aikawa, H.; Fujita, T.; Hoshino, K.; Kawashima, H.; Matsuda, T.; Maeno, M.; Mori, M.; Ogawa, H.; Shimada, M.; Uehara, K.; Yamauchi, T.

    1995-01-01

    The effects of divertor biasing and edge ergodization on the divertor plasma have been investigated in the JFT-2M tokamak. Experimental results show; (1) The differential divertor biasing can change the in/out asymmetry of the divertor plasma. It especially changes the density on the ion side divertor plasma. The in/out electron pressure difference has a good correlation with the biasing current. (2) The unipolar divertor biasing can change the density profile of divertor plasma. The radial electric field and shear flow are the cause for this change. (3) The electron temperature of the divertor plasma in the H-mode with frequent ELMs induced by edge ergodization is lower than that of usual H-mode. That is due to the enhancement of the radial particle flux by frequent ELMs, ((orig.))

  4. Ergodic averages for monotone functions using upper and lower dominating processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Mengersen, Kerrie

    We show how the mean of a monotone function (defined on a state space equipped with a partial ordering) can be estimated, using ergodic averages calculated from upper and lower dominating processes of a stationary irreducible Markov chain. In particular, we do not need to simulate the stationary...... Markov chain and we eliminate the problem of whether an appropriate burn-in is determined or not. Moreover, when a central limit theorem applies, we show how confidence intervals for the mean can be estimated by bounding the asymptotic variance of the ergodic average based on the equilibrium chain. Our...... methods are studied in detail for three models using Markov chain Monte Carlo methods and we also discuss various types of other models for which our methods apply....

  5. Ergodic averages for monotone functions using upper and lower dominating processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Mengersen, Kerrie

    2007-01-01

    We show how the mean of a monotone function (defined on a state space equipped with a partial ordering) can be estimated, using ergodic averages calculated from upper and lower dominating processes of a stationary irreducible Markov chain. In particular, we do not need to simulate the stationary...... Markov chain and we eliminate the problem of whether an appropriate burn-in is determined or not. Moreover, when a central limit theorem applies, we show how confidence intervals for the mean can be estimated by bounding the asymptotic variance of the ergodic average based on the equilibrium chain. Our...... methods are studied in detail for three models using Markov chain Monte Carlo methods and we also discuss various types of other models for which our methods apply....

  6. Thermodynamics and ergodicity of finite one-dimensional Toda and Morse lattices

    International Nuclear Information System (INIS)

    Likhachev, V.N.; Astakhova, T.Yu.; Vinogradov, G.A.

    2006-01-01

    The thermodynamics of finite one-dimensional lattices of particles interacting via Toda or Morse potentials is considered. An analysis is performed in canonical and microcanonical ensembles in 'temperature-lattice deformation' variables. Analytical results are obtained for thermodynamical values. It is demonstrated that small number of particles, e.g. N=10, is enough to get accurate approximation in the thermodynamical limit N->∼. The problem of the deformation rate is also investigated. It is found that the temperature increases at high deformation rate, and decreases at slow deformations. The Morse lattice was analyzed in numerical MD simulations in both canonical and microcanonical ensembles. The results are in qualitative agreement with the results for the Toda lattice. The finite Morse lattice is ergodic and the Toda lattice is non-ergodic. An excellent agreement between analytical and numerical results is obtained

  7. Novel relations between the ergodic capacity and the average bit error rate

    KAUST Repository

    Yilmaz, Ferkan

    2011-11-01

    Ergodic capacity and average bit error rate have been widely used to compare the performance of different wireless communication systems. As such recent scientific research and studies revealed strong impact of designing and implementing wireless technologies based on these two performance indicators. However and to the best of our knowledge, the direct links between these two performance indicators have not been explicitly proposed in the literature so far. In this paper, we propose novel relations between the ergodic capacity and the average bit error rate of an overall communication system using binary modulation schemes for signaling with a limited bandwidth and operating over generalized fading channels. More specifically, we show that these two performance measures can be represented in terms of each other, without the need to know the exact end-to-end statistical characterization of the communication channel. We validate the correctness and accuracy of our newly proposed relations and illustrated their usefulness by considering some classical examples. © 2011 IEEE.

  8. Boundary layer physics considerations for the TEXTOR dynamic ergodic divertor experiment

    Energy Technology Data Exchange (ETDEWEB)

    Evans, T.E. [General Atomics, San Diego, CA (United States)

    1997-09-01

    The proposed arrangement of the TEXTOR dynamic ergodic divertor coils is quite different from that of previous stochastic boundary layer experiments. These coils are located on the high field side and have continuous helical windings. The basic resonant magnetic field line structure is not substantially affected by the location of the perturbation coils but the non-resonant near field effects, such as those related to helical divertor effects and the interaction of the near field with the stochastic layer, are different. Differences with the TORE SUPRA ergodic divertor coils are discussed. Based on these differences we expect that the plasma positioning will play an important role in: (i) the onset of MARFE`s; (ii) the impurity screening efficiency; (iii) the onset of disruptions; and (iii) the transport properties of the boundary layer plasma. (orig.) 17 refs.

  9. Interview with Theo Rosier

    Directory of Open Access Journals (Sweden)

    Theo Rosier

    2011-06-01

    Full Text Available On 21 January 2009, the Amsterdam Court of Appeal had ordered the Public Prosecution Service (OM to subpoena Dutch politician Geert Wilders for, inter alia, spreading hatred and offending a group because of their religious convictions contrary to articles 137d and 137c of the Dutch Criminal Code. On Monday 24 May, the Amsterdam Court of First Instance rejected all preliminary objections formulated by Wilder's attorney Bram Moszkowicz. High time to scrutinise the precise merits of this prosecution and to re-examine an age old controversy: the perceived clash between the right to freedom of speech and (the right to freedom of religion.

  10. A novel ergodic capacity analysis of diversity combining and multihop transmission systems over generalized composite fading channels

    KAUST Repository

    Yilmaz, Ferkan

    2012-06-01

    Ergodic capacity is an important performance measure associated with reliable communication at the highest rate at which information can be sent over the channel with a negligible probability of error. In the shadow of this definition, diversity receivers (such as selection combining, equal-gain combining and maximal-ratio combining) and transmission techniques (such as cascaded fading channels, amplify-and-forward multihop transmission) are deployed in mitigating various performance impairing effects such as fading and shadowing in digital radio communication links. However, the exact analysis of ergodic capacity is in general not always possible for all of these forms of diversity receivers and transmission techniques over generalized composite fading environments due to it\\'s mathematical intractability. In the literature, published papers concerning the exact analysis of ergodic capacity have been therefore scarce (i.e., only [1] and [2]) when compared to those concerning the exact analysis of average symbol error probability. In addition, they are essentially targeting to the ergodic capacity of the maximal ratio combining diversity receivers and are not readily applicable to the capacity analysis of the other diversity combiners / transmission techniques. In this paper, we propose a novel moment generating function-based approach for the exact ergodic capacity analysis of both diversity receivers and transmission techniques over generalized composite fading environments. As such, we demonstrate how to simultaneously treat the ergodic capacity analysis of all forms of both diversity receivers and multihop transmission techniques. © 2012 IEEE.

  11. A new fuzzy Monte Carlo method for solving SLAE with ergodic fuzzy Markov chains

    Directory of Open Access Journals (Sweden)

    Maryam Gharehdaghi

    2015-05-01

    Full Text Available In this paper we introduce a new fuzzy Monte Carlo method for solving system of linear algebraic equations (SLAE over the possibility theory and max-min algebra. To solve the SLAE, we first define a fuzzy estimator and prove that this is an unbiased estimator of the solution. To prove unbiasedness, we apply the ergodic fuzzy Markov chains. This new approach works even for cases with coefficients matrix with a norm greater than one.

  12. Ergodicity for a Stochastic Geodesic Equation in the Tangent Bundle of the 2D Sphere

    Czech Academy of Sciences Publication Activity Database

    Baňas, L.; Brzezniak, Z.; Neklyudov, M.; Ondreját, Martin; Prohl, A.

    2015-01-01

    Roč. 65, č. 3 (2015), s. 617-657 ISSN 0011-4642 R&D Projects: GA ČR GAP201/10/0752 Institutional support: RVO:67985556 Keywords : geometric stochastic wave equation * stochastic geodesic equation * ergodicity * attractivity * invariant measure * numerical approximation Subject RIV: BA - General Mathematics Impact factor: 0.284, year: 2015 http://library.utia.cas.cz/separaty/2015/SI/ondrejat-0451399.pdf

  13. Impact of nonzero boresight pointing error on ergodic capacity of MIMO FSO communication systems.

    Science.gov (United States)

    Boluda-Ruiz, Rubén; García-Zambrana, Antonio; Castillo-Vázquez, Beatriz; Castillo-Vázquez, Carmen

    2016-02-22

    A thorough investigation of the impact of nonzero boresight pointing errors on the ergodic capacity of multiple-input/multiple-output (MIMO) free-space optical (FSO) systems with equal gain combining (EGC) reception under different turbulence models, which are modeled as statistically independent, but not necessarily identically distributed (i.n.i.d.) is addressed in this paper. Novel closed-form asymptotic expressions at high signal-to-noise ratio (SNR) for the ergodic capacity of MIMO FSO systems are derived when different geometric arrangements of the receive apertures at the receiver are considered in order to reduce the effect of nonzero inherent boresight displacement, which is inevitably present when more than one receive aperture is considered. As a result, the asymptotic ergodic capacity of MIMO FSO systems is evaluated over log-normal (LN), gamma-gamma (GG) and exponentiated Weibull (EW) atmospheric turbulence in order to study different turbulence conditions, different sizes of receive apertures as well as different aperture averaging conditions. It is concluded that the use of single-input/multiple-output (SIMO) and MIMO techniques can significantly increase the ergodic capacity respect to the direct path link when the inherent boresight displacement takes small values, i.e. when the spacing among receive apertures is not too big. The effect of nonzero additional boresight errors, which is due to the thermal expansion of the building, is evaluated in multiple-input/single-output (MISO) and single-input/single-output (SISO) FSO systems. Simulation results are further included to confirm the analytical results.

  14. Two-way DF relaying assisted D2D communication: ergodic rate and power allocation

    Science.gov (United States)

    Ni, Yiyang; Wang, Yuxi; Jin, Shi; Wong, Kai-Kit; Zhu, Hongbo

    2017-12-01

    In this paper, we investigate the ergodic rate for a device-to-device (D2D) communication system aided by a two-way decode-and-forward (DF) relay node. We first derive closed-form expressions for the ergodic rate of the D2D link under asymmetric and symmetric cases, respectively. We subsequently discuss two special scenarios including weak interference case and high signal-to-noise ratio case. Then we derive the tight approximations for each of the considered scenarios. Assuming that each transmitter only has access to its own statistical channel state information (CSI), we further derive closed-form power allocation strategy to improve the system performance according to the analytical results of the ergodic rate. Furthermore, some insights are provided for the power allocation strategy based on the analytical results. The strategies are easy to compute and require to know only the channel statistics. Numerical results show the accuracy of the analysis results under various conditions and test the availability of the power allocation strategy.

  15. Eigenstructures of MIMO Fading Channel Correlation Matrices and Optimum Linear Precoding Designs for Maximum Ergodic Capacity

    Directory of Open Access Journals (Sweden)

    Bahrami Hamid Reza

    2007-01-01

    Full Text Available The ergodic capacity of MIMO frequency-flat and -selective channels depends greatly on the eigenvalue distribution of spatial correlation matrices. Knowing the eigenstructure of correlation matrices at the transmitter is very important to enhance the capacity of the system. This fact becomes of great importance in MIMO wireless systems where because of the fast changing nature of the underlying channel, full channel knowledge is difficult to obtain at the transmitter. In this paper, we first investigate the effect of eigenvalues distribution of spatial correlation matrices on the capacity of frequency-flat and -selective channels. Next, we introduce a practical scheme known as linear precoding that can enhance the ergodic capacity of the channel by changing the eigenstructure of the channel by applying a linear transformation. We derive the structures of precoders using eigenvalue decomposition and linear algebra techniques in both cases and show their similarities from an algebraic point of view. Simulations show the ability of this technique to change the eigenstructure of the channel, and hence enhance the ergodic capacity considerably.

  16. Deterministic time-reversible thermostats: chaos, ergodicity, and the zeroth law of thermodynamics

    Science.gov (United States)

    Patra, Puneet Kumar; Sprott, Julien Clinton; Hoover, William Graham; Griswold Hoover, Carol

    2015-09-01

    The relative stability and ergodicity of deterministic time-reversible thermostats, both singly and in coupled pairs, are assessed through their Lyapunov spectra. Five types of thermostat are coupled to one another through a single Hooke's-law harmonic spring. The resulting dynamics shows that three specific thermostat types, Hoover-Holian, Ju-Bulgac, and Martyna-Klein-Tuckerman, have very similar Lyapunov spectra in their equilibrium four-dimensional phase spaces and when coupled in equilibrium or nonequilibrium pairs. All three of these oscillator-based thermostats are shown to be ergodic, with smooth analytic Gaussian distributions in their extended phase spaces (coordinate, momentum, and two control variables). Evidently these three ergodic and time-reversible thermostat types are particularly useful as statistical-mechanical thermometers and thermostats. Each of them generates Gibbs' universal canonical distribution internally as well as for systems to which they are coupled. Thus they obey the zeroth law of thermodynamics, as a good heat bath should. They also provide dissipative heat flow with relatively small nonlinearity when two or more such temperature baths interact and provide useful deterministic replacements for the stochastic Langevin equation.

  17. Occupation times and ergodicity breaking in biased continuous time random walks

    Energy Technology Data Exchange (ETDEWEB)

    Bel, Golan; Barkai, Eli [Physics Department, Bar-Ilan University, Ramat-Gan 52900 (Israel)

    2005-12-14

    Continuous time random walk (CTRW) models are widely used to model diffusion in condensed matter. There are two classes of such models, distinguished by the convergence or divergence of the mean waiting time. Systems with finite average sojourn time are ergodic and thus Boltzmann-Gibbs statistics can be applied. We investigate the statistical properties of CTRW models with infinite average sojourn time; in particular, the occupation time probability density function is obtained. It is shown that in the non-ergodic phase the distribution of the occupation time of the particle on a given lattice point exhibits bimodal U or trimodal W shape, related to the arcsine law. The key points are as follows. (a) In a CTRW with finite or infinite mean waiting time, the distribution of the number of visits on a lattice point is determined by the probability that a member of an ensemble of particles in equilibrium occupies the lattice point. (b) The asymmetry parameter of the probability distribution function of occupation times is related to the Boltzmann probability and to the partition function. (c) The ensemble average is given by Boltzmann-Gibbs statistics for either finite or infinite mean sojourn time, when detailed balance conditions hold. (d) A non-ergodic generalization of the Boltzmann-Gibbs statistical mechanics for systems with infinite mean sojourn time is found.

  18. Current profile control and magnetohydrodynamic stability in Tore Supra discharges with edge-plasma control by the ergodic divertor

    International Nuclear Information System (INIS)

    Zabiego, M.; Friant, C.; Ghendrih, P.; Becoulet, M.; Bucalossi, J.; Saint-Laurent, F.

    1999-01-01

    Although ergodic divertors are primarily designed to control particle and heat fluxes at the plasma edge, they also happen to affect the MHD stability of tokamak discharges. On Tore Supra, the ergodic divertor has long been known to stabilize the m/n=2/1 tearing mode induced, for instance, by edge radiation and detachment processes, thus allowing safe high-current and high-density operations. More recently, though, in discharges where ergodic divertor operations were optimised relative to the control of the edge-plasma (i.e., with large divertor perturbation), a detrimental increase in the disruptiveness has been observed. The action that the ergodic divertor has on the MHD activity is interpreted in terms of a redistribution of the current profile. The latter results from a large increase in the edge resistivity, primarily induced by the degradation of the electron energy confinement in the ergodic layer. The possibility that a transport barrier develops in the vicinity of the separatrix strongly affects the considered modelling. (authors)

  19. Experimental study of the topological aspect of the ergodic divertor in Tore-supra tokamak

    International Nuclear Information System (INIS)

    Costanzo, L.

    2001-10-01

    The control of power deposition onto plasma facing components in tokamaks is a determining factor for future thermonuclear fusion reactors. Plasma surface interaction can be performed using limiters or divertors. The ergodic divertor installed on Tore Supra is an atypical example of a magnetic divertor. It consists in applying a magnetic perturbation which establishes a particular topology of the plasma in contact with the wall (edge plasma). We carried out dedicated experiments in order to study parallel heat flux which strike the divertor neutralizers. This quantitative and qualitative analysis of heat flux as a function of experimental conditions allows to determine the profiles of power deposition along the neutralizers. The influence of plasma electron density, additional heating, impurities and injected gas was established. An experimental study of the sheath heat transmission factor γ was carried out by correlating measurements made with Langmuir probes and infrared imaging. This study gave rise to a major conclusion: for ohmic discharges with deuterium injection and most of the time with helium, it was experimentally confirmed that γ=7 in agreement with classical sheath theory. However, an increase of this factor with additional power has been shown. Detached plasma, which is an attractive regime in order to reduce the power deposition, requires an optimized control. A new measurement of the detachment onset has been developed. It is based on the variation of heat flux onto the plates derived from infrared measurements. A detachment cartography with the determination of a new 2D 'IR' Degree of Detachment was carried out allowing to locate the zone where the detachment starts. We can apply this concept both to other tokamaks such as JET and ITER. A comparison between the axisymmetric divertor and the ergodic divertor is also presented concerning the power deposition in the two configurations. Low heat flux with the ergodic divertor is a major advantage

  20. The virtual observatory service TheoSSA: Establishing a database of synthetic stellar flux standards . II. NLTE spectral analysis of the OB-type subdwarf Feige 110

    Science.gov (United States)

    Rauch, T.; Rudkowski, A.; Kampka, D.; Werner, K.; Kruk, J. W.; Moehler, S.

    2014-06-01

    Context. In the framework of the Virtual Observatory (VO), the German Astrophysical VO (GAVO) developed the registered service TheoSSA (Theoretical Stellar Spectra Access). It provides easy access to stellar spectral energy distributions (SEDs) and is intended to ingest SEDs calculated by any model-atmosphere code, generally for all effective temperatures, surface gravities, and elemental compositions. We will establish a database of SEDs of flux standards that are easily accessible via TheoSSA's web interface. Aims: The OB-type subdwarf Feige 110 is a standard star for flux calibration. State-of-the-art non-local thermodynamic equilibrium stellar-atmosphere models that consider opacities of species up to trans-iron elements will be used to provide a reliable synthetic spectrum to compare with observations. Methods: In case of Feige 110, we demonstrate that the model reproduces not only its overall continuum shape from the far-ultraviolet (FUV) to the optical wavelength range but also the numerous metal lines exhibited in its FUV spectrum. Results: We present a state-of-the-art spectral analysis of Feige 110. We determined , log g = 6.00 ± 0.20, and the abundances of He, N, P, S, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, and Ge. Ti, V, Mn, Co, Zn, and Ge were identified for the first time in this star. Upper abundance limits were derived for C, O, Si, Ca, and Sc. Conclusions: The TheoSSA database of theoretical SEDs of stellar flux standards guarantees that the flux calibration of astronomical data and cross-calibration between different instruments can be based on models and SEDs calculated with state-of-the-art model-atmosphere codes. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26666. Based on observations made with the NASA-CNES-CSA Far Ultraviolet Spectroscopic Explorer. Table 2, Figs. 3 and

  1. On the asymptotic ergodic capacity of FSO links with generalized pointing error model

    KAUST Repository

    Al-Quwaiee, Hessa

    2015-09-11

    Free-space optical (FSO) communication systems are negatively affected by two physical phenomenon, namely, scintillation due to atmospheric turbulence and pointing errors. To quantize the effect of these two factors on FSO system performance, we need an effective mathematical model for them. Scintillations are typically modeled by the log-normal and Gamma-Gamma distributions for weak and strong turbulence conditions, respectively. In this paper, we propose and study a generalized pointing error model based on the Beckmann distribution. We then derive the asymptotic ergodic capacity of FSO systems under the joint impact of turbulence and generalized pointing error impairments. © 2015 IEEE.

  2. Dynamical analysis of the magnetic field line evolution in tokamaks with ergodic limiters

    Energy Technology Data Exchange (ETDEWEB)

    Ullmann, Kai; Caldas, Ibere L. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica

    1997-12-31

    Full text. Magnetic ergodic limiters are commonly used to control chaos in the tokamak border and several models have been developed to study the influence of these limiters on the magnetic field line evolution in the tokamak vessel. In this work we derive a bidimensional symplectic mapping describing this evolution with toroidal corrections. Poincare plots presenting typical Hamiltonian behaviour, such as island chains and hetero clinic and homo clinic orbits are obtained. Then we perform the dynamical analysis of these Poincare plots using standard algorithms such as calculation of Lyapunov exponents, safety factors, FFT spectra and parameters space plots to perform the dynamical analysis. (author)

  3. Quantum unique ergodicity of Eisenstein series on the Hilbert modular group over a totally real field

    DEFF Research Database (Denmark)

    Truelsen, Jimi Lee

    2011-01-01

    W. Luo and P. Sarnak have proved the quantum unique ergodicity property for Eisenstein series on PSL(2, )\\. Their result is quantitative in the sense that they find the precise asymptotics of the measure considered. We extend their result to Eisenstein series on , where is the ring of integers...... in a totally real field of degree n over with narrow class number one, using the Eisenstein series considered by I. Efrat. We also give an expository treatment of the theory of Hecke operators on non-holomorphic Hilbert modular forms....

  4. Stationary distribution and ergodicity of a stochastic food-chain model with Lévy jumps

    Science.gov (United States)

    Yu, Jingyi; Liu, Meng

    2017-09-01

    In this paper, a three-species stochastic food-chain model with Lévy jumps is proposed and analyzed. Sharp sufficient criteria for the existence and uniqueness of an ergodic stationary distribution are established. The effects of Lévy jumps on the existence of the stationary distribution are revealed: in some cases, the Lévy jumps could make the stationary distribution appear, while in some cases, the Lévy jumps could make the stationary distribution disappear. Some numerical simulations are introduced to illustrate the theoretical results.

  5. Extended abstract: ergodic magnetic limiter experiments on TEXT with a 7/3 resonance

    International Nuclear Information System (INIS)

    deGrassie, J.S.; Ohyabu, N.; Brooks, N.H.

    1984-05-01

    The ergodic magnetic limiter coils on TEXT have been reconfigured to produce the primary helical perturbation resonance at m = 7 / n = 3. The experiments continue to demonstrate that the weak resonant perturbations modify the edge conditions in keeping with model predictions. We observe a reduction in the intrinsic impurity levels accompanying the helical current pulse, presumably the result of a reduction in the electron temperature in the edge. Heat follows the perturbed field lines to the limiter, generating heat load patterns which reflect the geometry of a magnetic island - limiter intersection. A strong spatial modulation of the electron density in the scrape-off-layer also reflects the helical mode structure

  6. Transport in the plasma edge specific connection to the wall in the Tore Supra ergodic divertor experiments

    International Nuclear Information System (INIS)

    Grosman, A.; Ghendrih, P.; DeMichelis, C.; Monier-Garbet, P.; Vallet, J.C.; Capes, H.; Chatelier, M.; Geraud, A.; Goniche, M.; Grisolia, C.; Guilhem, D.; Harris, G.; Hess, W.; Nguyen, F.; Poutchy, L.; Samain, A.

    1992-01-01

    The ergodic divertor experiments in TORE SUPRA can be analysed along two main lines. The first one refers to the change of the heat and particle transport in the ergodized zone. This is especially true for the electron heat transport which is enhanced in the edge layer. But other distinctive features give evidence of the importance of the parallel connexion length between the plasma edge and the wall. The field lines, which are stochastic in the major part of the perturbed layer (10-15 cm) are such that, in the outermost layer (3 cm), the connexion topology is regular. This has obvious effects on the particle and power deposition, but also on the plasma parameters, and consequently influences the particle recycling and impurity shielding processes. The TORE SUPRA ergodic divertor experiments are reviewed in this framework

  7. Orestes bojownikiem ruchu oporu, czyli mit Atrydów w filmie "Podróż komediantów" Theo Angelopoulosa

    Directory of Open Access Journals (Sweden)

    Iga Łomanowska

    2016-12-01

    Full Text Available Orestes as a resistance fighter, or the myth of the Atreides in Theo Angelopoulos’s film The travelling players The paper examines the use of the Atreides myth in Theo Angelopoulos’s film The travelling players (1975 in the context of the director’s interpretation of the phenomenon of myth. Angelopoulos treated myth as a set of archetypical situations and patterns of conduct constantly reproduced in the history of the world. He intertwined elements of classical stories with the history of Greece and the Byzantine tradition, thus showing their universal character. In The travelling players, Angelopoulos used the story of betrayed and murdered Agamemnon, who is avenged by his children: Orestes and Electra, but he moved it into modern times, setting the film in Greece of the 1940s and 1950s. The myth is reproduced with modulations: the most important events take place as a result of interventions of History, not fate or decisions of the gods. Moreover, the characters’ conflicts are enriched with a political dimension, as Angelopolous portrays the discord between their ideological stances. But the members of the acting company are as helpless in the face of events as the family of the king of Argos.   Orestes bojownikiem ruchu oporu, czyli mit Atrydów w filmie Podróż komediantów Theo Angelopoulosa Artykuł jest analizą sposobu wykorzystania przez Theo Angelopoulosa mitu Atrydów w filmie Podróż komediantów (1975 w kontekście dokonanej przez niego interpretacji zjawiska mitu. Grecki reżyser traktował mit jako zbiór archetypicznych sytuacji i wzorów postępowania odtwarzanych nieustannie w dziejach świata. Elementy antycznych opowieści splatał w filmach z historią Grecji i tradycją bizantyjską, ujawniając ich uniwersalny charakter. W Podróży komediantów wykorzystał historię zdradzonego i zamordowanego Agamemnona, który zostaje pomszczony przez swoje dzieci: Orestesa i Elektrę, ale przeniósł ją w czasy wsp

  8. Detection of progression of glaucomatous visual field damage using the point-wise method with the binomial test.

    Science.gov (United States)

    Karakawa, Ayako; Murata, Hiroshi; Hirasawa, Hiroyo; Mayama, Chihiro; Asaoka, Ryo

    2013-01-01

    To compare the performance of newly proposed point-wise linear regression (PLR) with the binomial test (binomial PLR) against mean deviation (MD) trend analysis and permutation analyses of PLR (PoPLR), in detecting global visual field (VF) progression in glaucoma. 15 VFs (Humphrey Field Analyzer, SITA standard, 24-2) were collected from 96 eyes of 59 open angle glaucoma patients (6.0 ± 1.5 [mean ± standard deviation] years). Using the total deviation of each point on the 2(nd) to 16(th) VFs (VF2-16), linear regression analysis was carried out. The numbers of VF test points with a significant trend at various probability levels (pbinomial test (one-side). A VF series was defined as "significant" if the median p-value from the binomial test was binomial PLR method (0.14 to 0.86) was significantly higher than MD trend analysis (0.04 to 0.89) and PoPLR (0.09 to 0.93). The PIS of the proposed method (0.0 to 0.17) was significantly lower than the MD approach (0.0 to 0.67) and PoPLR (0.07 to 0.33). The PBNS of the three approaches were not significantly different. The binomial BLR method gives more consistent results than MD trend analysis and PoPLR, hence it will be helpful as a tool to 'flag' possible VF deterioration.

  9. Stellar parameters for the central star of the planetary nebula PRTM 1 using the German Astrophysical Virtual Observatory service TheoSSA

    Science.gov (United States)

    Rauch, T.; Demleitner, M.; Hoyer, D.; Werner, K.

    2018-04-01

    The German Astrophysical Virtual Observatory (GAVO) developed the registered service TheoSSA (theoretical stellar spectra access) and the supporting registered VO tool TMAW (Tübingen Model-Atmosphere WWW interface). These allow individual spectral analyses of hot, compact stars with state-of-the-art non-local thermodynamical equilibrium (NLTE) stellar-atmosphere models that presently consider opacities of the elements H, He, C, N, O, Ne, Na, and Mg, without requiring detailed knowledge about the involved background codes and procedures. Presently, TheoSSA provides easy access to about 150 000 pre-calculated stellar spectral energy distributions (SEDs) and is intended to ingest SEDs calculated by any model-atmosphere code. In the case of the exciting star of PN PRTM 1, we demonstrate the easy way to calculate individual NLTE stellar model-atmospheres to reproduce an observed optical spectrum. We measured T_eff = 98 000± 5 000 K, log (g / cm/s^2) = 5.0^{+0.3}_{-0.2}, and photospheric mass fractions of H =7.5 × 10-1 (1.02 times solar), He =2.4 × 10-1 (0.96), C =2.0 × 10-3 (0.84), N =3.2 × 10-4 (0.46), and O =8.5 × 10-3 (1.48) with uncertainties of ±0.2 dex. We determined the stellar mass and luminosity of 0.73^{+0.16}_{-0.15} M_{⊙} and log (L/L⊙) = 4.2 ± 0.4, respectively.

  10. Fluctuations around equilibrium laws in ergodic continuous-time random walks.

    Science.gov (United States)

    Schulz, Johannes H P; Barkai, Eli

    2015-06-01

    We study occupation time statistics in ergodic continuous-time random walks. Under thermal detailed balance conditions, the average occupation time is given by the Boltzmann-Gibbs canonical law. But close to the nonergodic phase, the finite-time fluctuations around this mean are large and nontrivial. They exhibit dual time scaling and distribution laws: the infinite density of large fluctuations complements the Lévy-stable density of bulk fluctuations. Neither of the two should be interpreted as a stand-alone limiting law, as each has its own deficiency: the infinite density has an infinite norm (despite particle conservation), while the stable distribution has an infinite variance (although occupation times are bounded). These unphysical divergences are remedied by consistent use and interpretation of both formulas. Interestingly, while the system's canonical equilibrium laws naturally determine the mean occupation time of the ergodic motion, they also control the infinite and Lévy-stable densities of fluctuations. The duality of stable and infinite densities is in fact ubiquitous for these dynamics, as it concerns the time averages of general physical observables.

  11. On the ergodic secrecy capacity of the wiretap channel under imperfect main channel estimation

    KAUST Repository

    Rezki, Zouheir

    2011-11-01

    The ergodic secrecy capacity of the wiretap channel is known when the main channel (between the transmitter and the legitimate receiver) state information (CSI) is perfect at the transmitter and the coherence period is sufficiently large to enable random coding arguments in each block. In a fast fading scenario, when the codeword length spans many coherence periods, the secrecy capacity is still not known. In this paper, we present a framework that characterizes this secrecy capacity under imperfect main channel estimation at the transmitter. Inner and outer bounds on the ergodic secrecy capacity are derived for a class of independent identically distributed (i.i.d.) fading channels. The achievable rate is a simple on-off scheme using a Gaussian input. The upper bound is obtained using an appropriate correlation scheme of the main and the eavesdropper channels. The upper and the lower bounds coincide with recently derived ones in the perfect main CSI extreme. Furthermore, the lower bound matches the upper bound in no main CSI extreme, where the secrecy capacity is equal to zero. Numerical results are provided for independent identically distributed (i.i.d.) Rayleigh fading channels. © 2011 IEEE.

  12. Ergodic Capacity of Cognitive Radio Under Imperfect Channel-State Information

    KAUST Repository

    Rezki, Zouheir

    2012-09-08

    A spectrum-sharing communication system where the secondary user is aware of the instantaneous channel-state information (CSI) of the secondary link but knows only the statistics and an estimated version of the secondary transmitter-primary receiver link is investigated. The optimum power profile and the ergodic capacity of the secondary link are derived for general fading channels [with a continuous probability density function (pdf)] under the average and peak transmit power constraints and with respect to the following two different interference constraints: 1) an interference outage constraint and 2) a signal-to-interference outage constraint. When applied to Rayleigh fading channels, our results show, for example, that the interference constraint is harmful at the high-power regime, because the capacity does not increase with the power, whereas at the low-power regime, it has a marginal impact and no-interference performance, which corresponds to the ergodic capacity under average or peak transmit power constraint in the absence of the primary user, may be achieved. © 2012 IEEE.

  13. A Unified Framework for the Ergodic Capacity of Spectrum Sharing Cognitive Radio Systems

    KAUST Repository

    Sboui, Lokman

    2012-12-29

    We consider a spectrum sharing communication scenario in which a primary and a secondary users are communicating, simultaneously, with their respective destinations using the same frequency carrier. Both optimal power profile and ergodic capacity are derived for fading channels, under an average transmit power and an instantaneous interference outage constraints. Unlike previous studies, we assume that the secondary user has a noisy version of the cross link and the secondary link Channel State Information (CSI). After deriving the capacity in this case, we provide an ergodic capacity generalization, through a unified expression, that encompasses several previously studied spectrum sharing settings. In addition, we provide an asymptotic capacity analysis at high and low signal-to-noise ratio (SNR). Numerical results, applied for independent Rayleigh fading channels, show that at low SNR regime, only the secondary channel estimation matters with no effect of the cross link on the capacity; whereas at high SNR regime, the capacity is rather driven by the cross link CSI. Furthermore, a practical on-off power allocation scheme is proposed and is shown, through numerical results, to achieve the full capacity at high and low SNR regimes and suboptimal rates in the medium SNR regime.

  14. The influence of the dynamic ergodic divertor on the radial electric field at the Tokamak TEXTOR

    Energy Technology Data Exchange (ETDEWEB)

    Coenen, Jan Willem

    2009-11-06

    In this work the influence of external Resonant Magnetic Perturbations (RMPs) on the radial electric field Er in magnetically confined plasmas is investigated by Charge Exchange Recombination Spectroscopy (CXRS) at the Tokamak TEXTOR. Here, the RMPs are produced with the Dynamic Ergodic Divertor (DED), a set of 16 helical perturbation coils located at the high field side of TEXTOR. Within this work, the base mode number of perturbations has been m/n=6/2. We have first investigated the influence of external torque from neutral heating beams on plasma rotation and E{sub r}. The ergodic zone causes an electron loss, and subsequently a (vector)j x (vector)B force driven by the compensating ion return current. In addition, the DED changes the global confinement properties. Depending on the edge safety factor (''field line twist'') q{sub a}, either increased or decreased particle confinement is observed. In case of the increased particle confinement (IPC) the increase in density (40%) and particle confinement time {tau}{sub p} (30%) is correlated to the connection of field lines at the q=5/2 surface to the DED target, locally changing the transport properties and the E{sub r}. Transport is reduced and the E{sub r} shear is increased locally at q=5/2 up to 1.5 . 10{sup 5}s{sup -1}, while the E{sub r} becomes more positive. (orig.)

  15. A novel image encryption scheme based on the ergodicity of baker map

    Science.gov (United States)

    Ye, Ruisong; Chen, Yonghong

    2012-01-01

    Thanks to the exceptionally good properties in chaotic systems, such as sensitivity to initial conditions and control parameters, pseudo-randomness and ergodicity, chaos-based image encryption algorithms have been widely studied and developed in recent years. A novel digital image encryption scheme based on the chaotic ergodicity of Baker map is proposed in this paper. Different from traditional encryption schemes based on Baker map, we permute the pixel positions by their corresponding order numbers deriving from the approximating points in one chaotic orbit. To enhance the resistance to statistical and differential attacks, a diffusion process is suggested as well in the proposed scheme. The proposed scheme enlarges the key space significantly to resist brute-force attack. Additionally, the distribution of gray values in the cipher-image has a random-like behavior to resist statistical analysis. The proposed scheme is robust against cropping, tampering and noising attacks as well. It therefore suggests a high secure and efficient way for real-time image encryption and transmission in practice.

  16. Numerical analysis of tungsten transport in drift-optimized stellarator with ergodic and nonergodic plasma configurations

    Science.gov (United States)

    Shyshkin, Oleg A.; Schneider, Ralf; Beidler, Craig D.

    2007-11-01

    The radial transport of tungsten ions in a fusion plasma of the HELIAS stellarator with five magnetic field periods is studied by means of a new numerical code. The code solves guiding center equations for test particles (tungsten ions) with the use of a Runge-Kutta integrating scheme. Coulomb scattering of the tungsten ions on the background plasma particles (electrons, deuterons and tritons) is simulated by means of a discretized collision operator based on the binomial distribution and presented in terms of pitch-angle scattering and energy slowing down and scattering. The coronal model is used to determine the mean charge state of the tungsten ion ensemble langZ(Te, ne)rang as a function of background electron temperature and density. Two plasma configurations with and without ergodic confinement regions and both with finite plasma pressure of β = 3% are considered. The nonergodic configuration possesses closed nested magnetic surfaces throughout the entire confinement volume. The ergodic magnetic field configuration is represented through additional magnetic field perturbations. Comparative analysis of the radial transport is performed for a time interval greater by a factor of 15 than the energy confinement time τE = 1.62 s required for the HELIAS reactor. In spite of the fact that the tendency of impurities to penetrate towards the plasma core is observed in both cases, the stochastic scenario exhibits reduced inward impurity flux.

  17. On the ergodic capacity of legacy systems in the presence of next generation interference

    KAUST Repository

    Mahmood, Nurul Huda

    2011-11-01

    Next generation wireless systems facilitating better utilization of the scarce radio spectrum have emerged as a response to inefficient rigid spectrum assignment policies. These are comprised of intelligent radio nodes that opportunistically operate in the radio spectrum of existing legacy systems; yet unwanted interference at the legacy receivers is unavoidable. In order to design efficient next generation systems and to minimize their harmful consequences, it is necessary to realize their impact on the performance of legacy systems. In this work, a generalized framework for the ergodic capacity analysis of such legacy systems in the presence of interference from next generation systems is presented. The analysis is built around a model developed for the statistical representation of the interference at the legacy receivers, which is then used to evaluate the ergodic capacity of the legacy system. Moreover, this analysis is not limited to the context of legacy systems, and is in fact applicaple to any interference limited system. Findings of analytical performance analyses are confirmed through selected computer-based Monte-Carlo simulations. © 2011 IEEE.

  18. Ergodicity, configurational entropy and free energy in pigment solutions and plant photosystems: influence of excited state lifetime.

    Science.gov (United States)

    Jennings, Robert C; Zucchelli, Giuseppe

    2014-01-01

    We examine ergodicity and configurational entropy for a dilute pigment solution and for a suspension of plant photosystem particles in which both ground and excited state pigments are present. It is concluded that the pigment solution, due to the extreme brevity of the excited state lifetime, is non-ergodic and the configurational entropy approaches zero. Conversely, due to the rapid energy transfer among pigments, each photosystem is ergodic and the configurational entropy is positive. This decreases the free energy of the single photosystem pigment array by a small amount. On the other hand, the suspension of photosystems is non-ergodic and the configurational entropy approaches zero. The overall configurational entropy which, in principle, includes contributions from both the single excited photosystems and the suspension which contains excited photosystems, also approaches zero. Thus the configurational entropy upon photon absorption by either a pigment solution or a suspension of photosystem particles is approximately zero. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Mechanical design and manufacture of magnetic ergodic divertor for the TORE SUPRA tokamak

    International Nuclear Information System (INIS)

    Lipa, M.; Aymar, R.; Deschamps, P.; Hertout, P.; Portafaix, C.; Samain, A.

    1989-01-01

    A configuration of six equally spaced ergodic divertors has been chosen to control the plasma impurities in the TORE SUPRA tokamak since the control of these impurities is essential to the long pulse duration envisioned for the machine. Each of the six indentical modules is composed of (8) conductor bars arranged in a poloidal direction forming a resonant helical winding. The proximity of the conductors to the plasma requires that each copper assembly be water cooled, enclosed in a stainless steel casing and protected by pure graphite tiles attaches to the inner surface of the casing. Particles which drift between the coil bars are neutralized on actively water cooled neutralizer plates and then pumped out by titanium getter pumps which are located on each toroidal end of a divertor modul. (author). 5 refs.; 7 figs.; 1 tab

  20. Ergodic Capacity Analysis of Free-Space Optical Links with Nonzero Boresight Pointing Errors

    KAUST Repository

    Ansari, Imran Shafique

    2015-04-01

    A unified capacity analysis of a free-space optical (FSO) link that accounts for nonzero boresight pointing errors and both types of detection techniques (i.e. intensity modulation/ direct detection as well as heterodyne detection) is addressed in this work. More specifically, an exact closed-form expression for the moments of the end-to-end signal-to-noise ratio (SNR) of a single link FSO transmission system is presented in terms of well-known elementary functions. Capitalizing on these new moments expressions, we present approximate and simple closedform results for the ergodic capacity at high and low SNR regimes. All the presented results are verified via computer-based Monte-Carlo simulations.

  1. Threshold dynamics and ergodicity of an SIRS epidemic model with Markovian switching

    Science.gov (United States)

    Li, Dan; Liu, Shengqiang; Cui, Jing'an

    2017-12-01

    This paper studies the spread dynamics of a stochastic SIRS epidemic model with nonlinear incidence and varying population size, which is formulated as a piecewise deterministic Markov process. A threshold dynamic determined by the basic reproduction number R0 is established: the disease can be eradicated almost surely if R0 disease persists almost surely if R0 > 1. The existing method for analyzing ergodic behavior of population systems has been generalized. The modified method weakens the required conditions and has no limitations for both the number of environmental regimes and the dimension of the considered system. When R0 > 1, the existence of a stationary probability measure is obtained. Furthermore, with the modified method, the global attractivity of the Ω-limit set of the system and the convergence in total variation to the stationary measure are both demonstrated under a mild extra condition.

  2. The dynamic ergodic divertor in TEXTOR-A novel tool for studying magnetic perturbation field effects

    International Nuclear Information System (INIS)

    Neubauer, O.; Czymek, G.; Finken, K.H.; Giesen, B.; Huettemann, P.W.; Lambertz, H.T.; Schruff, J.

    2005-01-01

    Recently TEXTOR has been upgraded by the installation of the dynamic ergodic divertor (DED). The purpose of the DED is to influence transport parameters in plasma edge and core and to study the resulting effects on heat exhaust, edge cooling, impurity screening, plasma confinement and stability. Alternatively, the DED creates static or rotating multipolar helical magnetic perturbation fields of different mode patterns. A set of 16 helical coils has been installed on the inboard high-field side of the vacuum vessel. Rotating fields of up to 10 kHz can be generated. A novel coil design has been developed which fulfills the various mechanical, electrical, high frequency, thermal, and vacuum requirements. In addition to the various technical aspects of the DED design, implementation and commissioning, highlights of recent experiments will be presented. In particular the impact of the perturbation field on MHD stability and plasma rotation will be addressed

  3. Escape patterns due to ergodic magnetic limiters in tokamaks with reversed magnetic shear

    International Nuclear Information System (INIS)

    Roberto, M.; Da Silva, E.C.; Caldas, I.L.; Viana, R.L.

    2004-01-01

    In this work we study the ergodic magnetic limiters (EML) action on field lines from the point of view of a chaotic scattering process, considering the so-called exit basins, or sets of points in the chaotic region which originate field lines hitting the wall in some specified region. We divide the tokamak wall into three areas of equal poloidal angular length, corresponding to different exits for a chaotic field line. In order to obtain the exit basins we used a grid chosen inside a small rectangle which comprises a representative part of the chaotic region near the wall. Thus, exit basins were obtained for a tokamak wall with reversed magnetic shear. The no-twist mapping describes the perturbed magnetic field lines with two chains of magnetic islands and chaotic field lines in their vicinity. For a perturbing resonant magnetic field with a fixed helicity, the observed escape pattern changes with the perturbation intensity. (authors)

  4. On the continuing relevance of Mandelbrot's non-ergodic fractional renewal models of 1963 to 1967

    Science.gov (United States)

    Watkins, Nicholas W.

    2017-12-01

    The problem of "1/f" noise has been with us for about a century. Because it is so often framed in Fourier spectral language, the most famous solutions have tended to be the stationary long range dependent (LRD) models such as Mandelbrot's fractional Gaussian noise. In view of the increasing importance to physics of non-ergodic fractional renewal models, and their links to the CTRW, I present preliminary results of my research into the history of Mandelbrot's very little known work in that area from 1963 to 1967. I speculate about how the lack of awareness of this work in the physics and statistics communities may have affected the development of complexity science, and I discuss the differences between the Hurst effect, "1/f" noise and LRD, concepts which are often treated as equivalent. Contribution to the "Topical Issue: Continuous Time Random Walk Still Trendy: Fifty-year History, Current State and Outlook", edited by Ryszard Kutner and Jaume Masoliver.

  5. Outage Probability and Ergodic Capacity of Spectrum-Sharing Systems with MRC Diversity

    Science.gov (United States)

    Jarrouj, Jiana; Blagojevic, Vesna; Ivanis, Predrag

    2016-03-01

    The spectrum sharing system employing maximum ratio combining (MRC) is analyzed in Nakagami fading environment, for the case when the interference from the primary user is present at the input of the secondary user receiver. The closed-form expressions for the probability density function of the signal-to-interference-and-noise ratio, the outage probability and the ergodic capacity of the SU link are derived under both peak interference and maximal transmit power constraints. Asymptotical expressions are provided for the important region where peak interference power constraint dominates and the case when the interference from the primary user's is dominant compared to the noise at the secondary user's receiver. The obtained expressions are presented for both cases of outdated and mean-value based power allocation and verified by using Monte Carlo simulation method.

  6. Ergodic properties and thermodynamic behavior of elementary reversible cellular automata. I. Basic properties

    International Nuclear Information System (INIS)

    Takesue, Shinji

    1989-01-01

    This is the first part of a series devoted to the study of thermodynamic behavior of large dynamical systems with the use of a family of full-discrete and conservative models named elementary reversible cellular automata (ERCAs). In this paper, basic properties such as conservation laws and phase space structure are investigated in preparation for the later studies. ERCAs are a family of one-dimensional reversible cellular automata having two Boolean variables on each site. Reflection and Boolean conjugation symmetries divide them into 88 equivalence classes. For each rule, additive conserved quantities written in a certain form are regarded as a kind of energy, if they exist. By the aid of the discreteness of the variables, every ERCA satisfies the Liouville theorem or the preservation of phase space volume. Thus, if an energy exists in the above sense, statistical mechanics of the model can formally be constructed. If a locally defined quantity is conserved, however, it prevents the realization of statistical mechanics. The existence of such a quantity is examined for each class and a number of rules which have at least one energy but no local conservation laws are selected as hopeful candidates for the realization of thermodynamic behavior. In addition, the phase space structure of ERCAs is analyzed by enumerating cycles exactly in the phase space for systems of comparatively small sizes. As a result, it is revealed that a finite ERCA is not ergodic, that is, a large number of orbits coexist on an energy surface. It is argued that this fact does not necessarily mean the failure of thermodynamic behavior on the basis of an analogy with the ergodic nature of infinite systems

  7. Flow and transport in digitized images of Berea sandstone: ergodicity, stationarity and upscaling

    Science.gov (United States)

    Puyguiraud, A.; Dentz, M.; Gouze, P.

    2017-12-01

    We perform Stokes flow simulations on digitized images of a Berea sandstone sample obtained through micro-tomography imaging and segmentation processes. We obtain accurate information on the transport using a streamline reconstruction algorithm which uses the velocity field obtained from the flow simulation as input data. This technique is based on the method proposed by Pollock (Groundwater, 1988) but employs a quadratic interpolation near the rock mesh cells of the domain similarly to Mostaghimi et al. (SPE, 2012). This allows an accurate resolution of the velocity field near the solid interface which plays an important role on the transport characteristics, such as the probability density of first arrival times and the growth of the mean squared displacement, among others, which exhibit non-Fickian behavior. We analyze Lagrangian and Eulerian velocity statistics and their relation, and then focus on the ergodicity and the stationarity properties of the transport.We analyze the temporal evolution of Lagrangian velocity statistics for different injection conditions, and findd quick convergence to a limiting velocity distribution, indicating the transport to be near-stationary. The equivalence between velocity samplings within and across streamlines, as well as the independency of the statistics on the number of sampled streamlines, lead as to conclude that the transport may be modeled as ergodic.These characteristics then allow us to upscale the 3-dimensional simulations using a 1-dimensional Continuous Time Random Walk model. This model, parametrized by the velocity results and the characteristic correlation length obtained from the above mentioned simulations, is able to efficiently reproduce the results and to predict larger scale behaviors.

  8. Particle exhaust with vented structures: application to the ergodic divertor of Tore Supra

    International Nuclear Information System (INIS)

    Azeroual, A.

    2000-01-01

    In a thermonuclear reactor, one must continuously fuel the discharge and extract the ashes resulting from fusion reactions. To avoid the risk of discharge poisoning, α-particle concentration is limited to ∼ 10 %. To allow for steady-state conditions requires then to extract ≥2 % of the helium out flux. In Tore Supra, the ergodic divertor is the main component managing the heat and particle fluxes at the edge. Its principle consists in generating a resonant perturbation able to destroy magnetic surfaces at the plasma periphery. In this region, the field lines are open and connected at both ends to neutralizers which are wetted by the major part of the heat and particle fluxes and are the structures through which a part of the plasma out flux is pumped for maintaining the discharge in steady-state conditions. This work describes the neutral recirculation around the ergodic divertor and is based on a data base of 56 discharges. One discuss the two processes allowing for particle exhaust: the ballistic collection of ions and that of neutrals backscattered by atomic reactions. These two processes are modelled accounting for a realistic description of the divertor geometry. A comparison between simulations and experiments is presented for measurements characterising the three main actors of plasma-wall interaction: the edge plasma, the D α light emission and the neutral pressure in the divertor plenum. Last, one question how such a system can be extrapolated to next step machines, for which one must account for technical constraints linked to the presence of the shield protecting the coils from the high neutron flux. (author)

  9. Ergodicity of Truncated Stochastic Navier Stokes with Deterministic Forcing and Dispersion

    Science.gov (United States)

    Majda, Andrew J.; Tong, Xin T.

    2016-10-01

    Turbulence in idealized geophysical flows is a very rich and important topic. The anisotropic effects of explicit deterministic forcing, dispersive effects from rotation due to the β -plane and F-plane, and topography together with random forcing all combine to produce a remarkable number of realistic phenomena. These effects have been studied through careful numerical experiments in the truncated geophysical models. These important results include transitions between coherent jets and vortices, and direct and inverse turbulence cascades as parameters are varied, and it is a contemporary challenge to explain these diverse statistical predictions. Here we contribute to these issues by proving with full mathematical rigor that for any values of the deterministic forcing, the β - and F-plane effects and topography, with minimal stochastic forcing, there is geometric ergodicity for any finite Galerkin truncation. This means that there is a unique smooth invariant measure which attracts all statistical initial data at an exponential rate. In particular, this rigorous statistical theory guarantees that there are no bifurcations to multiple stable and unstable statistical steady states as geophysical parameters are varied in contrast to claims in the applied literature. The proof utilizes a new statistical Lyapunov function to account for enstrophy exchanges between the statistical mean and the variance fluctuations due to the deterministic forcing. It also requires careful proofs of hypoellipticity with geophysical effects and uses geometric control theory to establish reachability. To illustrate the necessity of these conditions, a two-dimensional example is developed which has the square of the Euclidean norm as the Lyapunov function and is hypoelliptic with nonzero noise forcing, yet fails to be reachable or ergodic.

  10. Timelike Rotational Surfaces of Elliptic, Hyperbolic and Parabolic Types in Minkowski Space E-1(4) with Pointwise 1-Type Gauss Map

    OpenAIRE

    Bektaş, Burcu; Dursun, Uğur

    2015-01-01

    In this work, we focus on a class of timelike rotational surfaces in Minkowski space E-1(4) with 2-dimensional axis. There are three types of rotational surfaces with 2-dimensional axis, called rotational surfaces of elliptic, hyperbolic or parabolic type. We obtain all flat timelike rotational surface of elliptic and hyperbolic types with pointwise 1-type Gauss map of the first and second kind. We also prove that there exists no flat timelike rotational surface of parabolic type in E-1(4) wi...

  11. THE ONENESS OF GOD BEHIND THE LOCAL TRADITION OF NUSANTARA ISLAM: THEO-ANTHROPOLOGICAL PERSPECTIVE WITH INTERPRETIVE PARADIGM ON NUSANTARA ISLAM SASAK LOMBOK

    Directory of Open Access Journals (Sweden)

    Mohamad Iwan Fitriani

    2016-05-01

    Full Text Available This study aims to elucidate Nusantara Islam and finds the concept of oneness of God within the Sasak Muslim traditions as analytical tool to understand Nusantara Islam in the local context of Lombok. God is only one, but ways of finding “The One” vary. Islamic teachings manifest in local traditions are termed Nusantara Islam. In this study, Nusantara Islam is analyzed theoretically and practically regarding Sasak Muslim traditions. This study uses a qualitative approach and employs the interpretive paradigm and Theo-anthropological perspective. This study shows that Nusantara Islam in Lombok can be observed through various religious concepts, practices and rituals, such as mulut (the celebration of Prophet’s birthday, maleman (last ten days of fasting Ramadan month and rowah (sending prayer to the dead. Tawḥīd or the notion of One God lies behind these traditions. Tawḥīd is more than just the notion of oneness of God; it is a worldview manifesting not only in spiritual domains but also in socio-cultural spheres.

  12. Can Hindered Intramolecular Vibrational Energy Redistribution Lead to Non-Ergodic Behavior of Medium-Sized Ion Pairs?

    Czech Academy of Sciences Publication Activity Database

    Shaffer, Christopher; Révész, Agnes; Schröder, Detlef; Severa, Lukáš; Teplý, Filip; Zins, E. L.; Jašíková, L.; Roithová, J.

    2012-01-01

    Roč. 51, č. 40 (2012), s. 10050-10053 ISSN 1433-7851 R&D Projects: GA ČR GAP207/10/2391 Grant - others:European Research Council(XE) StG ISORI; European Research Council(XE) AdG HORIZOMS Institutional support: RVO:61388963 Keywords : IR spectroscopy * ion pairs * non-ergodic behavior * ions * triflate * pyridinium ions Subject RIV: CC - Organic Chemistry Impact factor: 13.734, year: 2012

  13. Fluorescence molecule counting for single-molecule studies in crowded environment of living cells without and with broken ergodicity.

    Science.gov (United States)

    Földes-Papp, Zeno; Baumann, Gerd

    2011-05-01

    We present a new approach to distinguish between non-ergodic and ergodic behavior. Performing ensemble averaging in a subpopulation of individual molecules leads to a mean value that can be similar to the mean value obtained in an ergodic system. The averaging is carried out by minimizing the variation between the sum of the temporal averaged mean square deviation of the simulated data with respect to the logarithmic scaling behavior of the subpopulation. For this reason, we first introduce a kind of Continuous Time Random Walks (CTRW), which we call Limited Continuous Time Random Walks (LCTRW) on fractal support. The random waiting time distributions are sampled at points which fulfill the condition N <1, where N is the Poisson probability of finding a single molecule in the femtoliter-sized observation volume ΔV at the single-molecule level. Given a subpopulation of different single molecules of the same kind, the ratio T/ T(m) between the measurement time T and the meaningful time T(m), which is the time for observing just one and the same single molecule, is the experimentally accessible quantity that allows to compare different molecule numbers in the subpopulation. In addition, the mean square displacement traveled by the molecule during the time t is determined by an upper limit of the geometric dimension of the living cell or its nucleus.

  14. Simultaneous multifractal decompositions for the spectra of local entropies and ergodic averages

    International Nuclear Information System (INIS)

    Meson, Alejandro; Vericat, Fernando

    2009-01-01

    We consider different multifractal decompositions of the form K α i ={x:g i (x)=α i },i=1,2,...,d, and we study the dimension spectrum corresponding to the multiparameter decomposition K α = intersection i=1 d K α i ,α=(α 1 ,...,α d ). Then for an homeomorphism f : X → X and potentials φ, ψ : X → R we analyze the decompositions K α + ={x:lim n→∞ 1/n (S n + (φ))(x)=α},K β - ={x:lim n→∞ 1/n (S n - (ψ))(x)=β}, where 1/n (S n + (φ)),1/n (S n - (ψ)) are ergodic averages using forward and backward orbits of f respectively. We must emphasize that the analysis, in any case, is done without requiring conditions of hyperbolicity for the dynamical system or Hoelder continuity on the potentials. We illustrate with an application to galactic dynamics: a set of stars (which do not interact among them) moving in a galactic field.

  15. The ergodic limit of multipass absorption for fast wave current drive in tokamaks

    Science.gov (United States)

    Kupfer, K.; Forest, C. B.; Petty, C. C.; Pinsker, R. I.

    1994-12-01

    In many parameter regimes of interest for fast wave current drive (FWCD) in tokamaks, direct absorption of the fast wave by resonant electrons is a weak process and multipass absorption is an important issue. Although both full wave codes and ray tracing codes have been developed to model FWCD, in the multipass regime these tools are computationally intensive, and yield little insight into the nature of the solutions. In this work, an alternative approach is considered. Based on the wave kinetic equation, a natural limit emerges for the multipass regime, where wave energy density, convected along stochastic ray trajectories, uniformly fills the entire accessible phase space. In this ergodic, weak damping limit, the absorbed power density and corresponding wave-driven current density are readily obtained by calculating the appropriate set of one-dimensional k-space integrals at every point in configuration space. The method is used here to model FWCD on the DIII-D tokamak [R. I. Pinsker and the DIII-D Team, Plasma Physics and Controlled Nuclear Fusion Research 1992 (International Atomic Energy Agency, Vienna, 1993), Vol. 1, p. 683]. An example for reactor-grade plasma parameters is also considered.

  16. Public-Private Partnerships (PPP on moulding state structures: The Non-Ergodic Africa

    Directory of Open Access Journals (Sweden)

    Fred Amonya

    2016-10-01

    Full Text Available Public-Private Partnerships (PPP is a ubiquitous reality. In Africa, the wave of PPP has hit states in their infancy – still moulding following only 50 years since independence. The common perspective of PPP on the realms of scholarship is transactional (focused on the delivery-end of infrastructure. This paper presents a deeper and broader perspective, and it is a distillate of a case study on PPP as a policy phenomenon. It dissects and illuminates the interaction between the forces of state formation and the wave of PPP hitting the continent. The lens of this case study is Institutional Rational Choice (IRC. The tools are a variety, comprising textual analysis, hermeneutics and econometrics – in keeping with the essence of case study (explication of reality in-situ. The product is not the orthodox generalization (claiming ‘the way’. Instead, the explication offers a viewpoint (and trigger questions on public space of Africa, while underpinning the non-ergodic character of that space

  17. On the ergodic secret message capacity of the wiretap channel with finite-rate feedback

    KAUST Repository

    Rezki, Zouheir

    2012-07-01

    We study the secret message capacity of an ergodic block fading wiretap channel with partial channel state information at the transmitter and perfect channel state information at the receivers. We consider that in addition to the statistics of the main and the eavesdropper channel state information (CSI), the sender is provided by the legitimate receiver with a q-bit feedback, at the beginning of each coherence block, through an error-free feedback channel, with capacity q bits. We establish upper and lower bounds on the secrecy capacity. We show that a positive secrecy rate is achievable even when the feedback is at the end of each coherence block and q = 1. We also show that the lower and the upper bounds coincide asymptotically as q → ∞. Finally, asymptotic analysis at high Signal-to-Noise Ratio (SNR) are presented where it is found that the capacity is bounded at high-SNR and present a simple suboptimal scalar quantizer that is capacity achieving, without the need of any numerical optimization, as q → ∞. When applied to Rayleigh fading channels, we show that, at high-SNR, a 4-bit feedback achieves 90% of the secrecy capacity when perfect main CSI is available at the transmitter. © 2012 IEEE.

  18. Geometric ergodicity of a hybrid sampler for Bayesian inference of phylogenetic branch lengths.

    Science.gov (United States)

    Spade, David A; Herbei, Radu; Kubatko, Laura S

    2015-10-01

    One of the fundamental goals in phylogenetics is to make inferences about the evolutionary pattern among a group of individuals, such as genes or species, using present-day genetic material. This pattern is represented by a phylogenetic tree, and as computational methods have caught up to the statistical theory, Bayesian methods of making inferences about phylogenetic trees have become increasingly popular. Bayesian inference of phylogenetic trees requires sampling from intractable probability distributions. Common methods of sampling from these distributions include Markov chain Monte Carlo (MCMC) and Sequential Monte Carlo (SMC) methods, and one way that both of these methods can proceed is by first simulating a tree topology and then taking a sample from the posterior distribution of the branch lengths given the tree topology and the data set. In many MCMC methods, it is difficult to verify that the underlying Markov chain is geometrically ergodic, and thus, it is necessary to rely on output-based convergence diagnostics in order to assess convergence on an ad hoc basis. These diagnostics suffer from several important limitations, so in an effort to circumvent these limitations, this work establishes geometric convergence for a particular Markov chain that is used to sample branch lengths under a fairly general class of nucleotide substitution models and provides a numerical method for estimating the time this Markov chain takes to converge. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Bistability, non-ergodicity, and inhibition in pairwise maximum-entropy models.

    Science.gov (United States)

    Rostami, Vahid; Porta Mana, PierGianLuca; Grün, Sonja; Helias, Moritz

    2017-10-01

    Pairwise maximum-entropy models have been used in neuroscience to predict the activity of neuronal populations, given only the time-averaged correlations of the neuron activities. This paper provides evidence that the pairwise model, applied to experimental recordings, would produce a bimodal distribution for the population-averaged activity, and for some population sizes the second mode would peak at high activities, that experimentally would be equivalent to 90% of the neuron population active within time-windows of few milliseconds. Several problems are connected with this bimodality: 1. The presence of the high-activity mode is unrealistic in view of observed neuronal activity and on neurobiological grounds. 2. Boltzmann learning becomes non-ergodic, hence the pairwise maximum-entropy distribution cannot be found: in fact, Boltzmann learning would produce an incorrect distribution; similarly, common variants of mean-field approximations also produce an incorrect distribution. 3. The Glauber dynamics associated with the model is unrealistically bistable and cannot be used to generate realistic surrogate data. This bimodality problem is first demonstrated for an experimental dataset from 159 neurons in the motor cortex of macaque monkey. Evidence is then provided that this problem affects typical neural recordings of population sizes of a couple of hundreds or more neurons. The cause of the bimodality problem is identified as the inability of standard maximum-entropy distributions with a uniform reference measure to model neuronal inhibition. To eliminate this problem a modified maximum-entropy model is presented, which reflects a basic effect of inhibition in the form of a simple but non-uniform reference measure. This model does not lead to unrealistic bimodalities, can be found with Boltzmann learning, and has an associated Glauber dynamics which incorporates a minimal asymmetric inhibition.

  20. Ergodic secret message capacity of the wiretap channel with finite-rate feedback

    KAUST Repository

    Rezki, Zouheir

    2014-06-01

    We study the secret message capacity of an ergodic block fading wiretap channel with partial channel state information at the transmitter and perfect channel state information at the receivers, under both a short term power constraint (STPC) and a long term power constraint (LTPC). We consider that in addition to the statistics of the main and the eavesdropper channel state information (CSI), the sender is provided by the legitimate receiver with a q-bit feedback, at the beginning of each coherence block, through an error-free public channel, with capacity q bits. We establish upper and lower bounds on the secrecy capacity. We show that the lower and the upper bounds coincide asymptotically as q → ∞. When applied to Rayleigh fading channels, we show that, a 4-bit feedback achieves about 90% of the secrecy capacity when perfect main CSI is available at the transmitter. Finally, asymptotic analysis at high and low Signal-to-Noise Ratio (SNR) is presented. It is found that the capacity is bounded at high-SNR, whereas at asymptotically low-SNR, the lower bounds and the upper bound scale linearly with SNR under STPC. Furthermore, subject to LTPC, the capacity at low-SNR is equal to the capacity of the main channel without secrecy constraint and with perfect CSI at both the transmitter and the receiver, under a mild condition on the fading statistics. We also show that a positive secrecy rate is achievable even when the feedback is at the end of each coherence block and q=1. © 2002-2012 IEEE.

  1. Teachers of a Pedagogy degree in a distance education program: use of digital libraries from the ergodic literature perspective

    OpenAIRE

    Sindier Antônia Alves; Heitor Garcia de Carvalho

    2011-01-01

    : In this article, the way digital libraries are used  by undergraduate students of a Pedagogy degree in a Distance Education program is researched through concepts such as digital library, print library, and informational behavior. Based uponEspen Aarseth’s Theory of Ergodic Literature, this research consisted of some semi-structured interviews aiming at checking how the digital library was used in this program. The collected data showed that students did have access to technology, however t...

  2. Dynamics and stability of rigid rotors levitated by passive cylinder-magnet bearings and driven/supported axially by pointwise contact clutch

    Science.gov (United States)

    Andersen, Søren B.; Enemark, Søren; Santos, Ilmar F.

    2013-12-01

    A stable rotor—supported laterally by passive magnetic bearings and longitudinally by magnetic forces and a clutch—loses suddenly its contact to the clutch and executes abruptly longitudinal movements away from its original equilibrium position as a result of small increases in angular velocity. Such an abrupt unstable behaviour and its reasons are thoroughly theoretically as well as experimentally investigated in this work. In this context, this paper gives theoretical as well as experimental contributions to the problem of two dimensional passive magnetic levitation and one dimensional pointwise contact stability dictated by mechanical-magnetic interaction. Load capacity and stiffness of passive multicylinder magnetic bearings (MCMB) are thoroughly investigated using two theoretical approaches followed by experimental validation. The contact dynamics between the clutch and the rotor supported by MCMB using several configurations of magnet distribution are described based on an accurate nonlinear model able to reliably reproduce the rotor-bearing dynamic behaviour. Such investigations lead to: (a) clear physical explanation about the reasons for the rotor's unstable behaviour, losing its contact to the clutch and (b) an accurate prediction of the threshold of stability based on the nonlinear rotor-bearing model, i.e. maximum angular velocity before the rotor misses its contact to the clutch as a function of rotor, bearing and clutch design parameters. passive cylinder-magnet bearings, imbalance ring with a screw, passive rotating cylinder-magnets, rotor, Pointwise contact clutch, and DC-motor. The rotor (4) is levitated in the two horseshoe-shaped bearing houses (1) which contain several cylinder-magnets arranged in a circular pattern. These permanent magnets form a magnetic field around the rotor which repels similar cylinder-magnets (3) embedded in the rotor, thereby counteracting the gravity forces. As the shape of the magnetic field generated by the

  3. The Virtual Observatory Service TheoSSA: Establishing a Database of Synthetic Stellar Flux Standards I. NLTE Spectral Analysis of the DA-Type White Dwarf G191-B2B *,**,***,****

    Science.gov (United States)

    Rauch, T.; Werner, K.; Bohlin, R.; Kruk, J. W.

    2013-01-01

    Hydrogen-rich, DA-type white dwarfs are particularly suited as primary standard stars for flux calibration. State-of-the-art NLTE models consider opacities of species up to trans-iron elements and provide reliable synthetic stellar-atmosphere spectra to compare with observations. Aims. We will establish a database of theoretical spectra of stellar flux standards that are easily accessible via a web interface. Methods. In the framework of the Virtual Observatory, the German Astrophysical Virtual Observatory developed the registered service TheoSSA. It provides easy access to stellar spectral energy distributions (SEDs) and is intended to ingest SEDs calculated by any model-atmosphere code. In case of the DA white dwarf G191-B2B, we demonstrate that the model reproduces not only its overall continuum shape but also the numerous metal lines exhibited in its ultraviolet spectrum. Results. TheoSSA is in operation and contains presently a variety of SEDs for DA-type white dwarfs. It will be extended in the near future and can host SEDs of all primary and secondary flux standards. The spectral analysis of G191-B2B has shown that our hydrostatic models reproduce the observations best at Teff =60 000 +/- 2000K and log g=7.60 +/- 0.05.We newly identified Fe vi, Ni vi, and Zn iv lines. For the first time, we determined the photospheric zinc abundance with a logarithmic mass fraction of -4.89 (7.5 × solar). The abundances of He (upper limit), C, N, O, Al, Si, O, P, S, Fe, Ni, Ge, and Sn were precisely determined. Upper abundance limits of about 10% solar were derived for Ti, Cr, Mn, and Co. Conclusions. The TheoSSA database of theoretical SEDs of stellar flux standards guarantees that the flux calibration of all astronomical data and cross-calibration between different instruments can be based on the same models and SEDs calculated with different model-atmosphere codes and are easy to compare.

  4. Mean-Field Critical Behavior and Ergodicity Break in a Nonequilibrium One-Dimensional Rsos Growth Model

    Science.gov (United States)

    Mendonça, J. Ricardo G.

    We investigate the nonequilibrium roughening transition of a one-dimensional restricted solid-on-solid model by directly sampling the stationary probability density of a suitable order parameter as the surface adsorption rate varies. The shapes of the probability density histograms suggest a typical Ginzburg-Landau scenario for the phase transition of the model, and estimates of the "magnetic" exponent seem to confirm its mean-field critical behavior. We also found that the flipping times between the metastable phases of the model scale exponentially with the system size, signaling the breaking of ergodicity in the thermodynamic limit. Incidentally, we discovered that a closely related model not considered before also displays a phase transition with the same critical behavior as the original model. Our results support the usefulness of off-critical histogram techniques in the investigation of nonequilibrium phase transitions. We also briefly discuss in the appendix a good and simple pseudo-random number generator used in our simulations.

  5. Equilibrium statistical mechanics for self-gravitating systems: local ergodicity and extended Boltzmann-Gibbs/White-Narayan statistics

    Science.gov (United States)

    He, Ping

    2012-01-01

    The long-standing puzzle surrounding the statistical mechanics of self-gravitating systems has not yet been solved successfully. We formulate a systematic theoretical framework of entropy-based statistical mechanics for spherically symmetric collisionless self-gravitating systems. We use an approach that is very different from that of the conventional statistical mechanics of short-range interaction systems. We demonstrate that the equilibrium states of self-gravitating systems consist of both mechanical and statistical equilibria, with the former characterized by a series of velocity-moment equations and the latter by statistical equilibrium equations, which should be derived from the entropy principle. The velocity-moment equations of all orders are derived from the steady-state collisionless Boltzmann equation. We point out that the ergodicity is invalid for the whole self-gravitating system, but it can be re-established locally. Based on the local ergodicity, using Fermi-Dirac-like statistics, with the non-degenerate condition and the spatial independence of the local microstates, we rederive the Boltzmann-Gibbs entropy. This is consistent with the validity of the collisionless Boltzmann equation, and should be the correct entropy form for collisionless self-gravitating systems. Apart from the usual constraints of mass and energy conservation, we demonstrate that the series of moment or virialization equations must be included as additional constraints on the entropy functional when performing the variational calculus; this is an extension to the original prescription by White & Narayan. Any possible velocity distribution can be produced by the statistical-mechanical approach that we have developed with the extended Boltzmann-Gibbs/White-Narayan statistics. Finally, we discuss the questions of negative specific heat and ensemble inequivalence for self-gravitating systems.

  6. Study of production, transport and radiation of carbon impurities near the ergodic divertor in Tore-Supra tokamak

    International Nuclear Information System (INIS)

    Corre, Y.

    2001-11-01

    In a Tokamak thermonuclear reactor, the impurity control is essential to keep the plasma in fusion conditions. Indeed, the impurities which enter the bulk are responsible for the fuel dilution (and hence a significant reduction of the number of fusion reactions). The pollution of fusion plasma by impurities has thus to be as low as possible. In the Tokamak Tore Supra, as in most present day Tokamaks, the main impurity is carbon. First, we have studied the carbon production mechanisms on the Neutralizer Plates of the Tore Supra Ergodic Divertor (where the plasma surface interaction is the most important). For this purpose we have used an endoscope during an experimental campaign in order to measure spectral line brightnesses emitted in the visible wavelength range by low charge carbon ions. The quantitative analysis of the pictures provided by this endoscope, together with measurements by other plasma edge diagnostics, has allowed us to estimate the atom flux extracted from the neutralizer plates during the various density regimes accessed in ED configuration. We have deduced from these calculations an experimental sputtering yield. A comparison with the theoretical sputtering yield allows us to determine the dominant erosion mechanism as a function of the edge plasma density and temperature. This comparative analysis shows that when the edge electron temperature is above 30 eV, the self-sputtering process is the dominant phenomenon for impurity production and bulk contamination. When T e bord is high, the effective erosion is bigger than the erosion due to deuterium ion impacts. This information has then been used to study transport and radiation of this impurity near the neutralizer plates with the 3-D Monte Carlo code BBQ (grill) and other carbon radiation measurements. It has allowed us to characterise the circulation of carbon in the plasma edge and to determine the carbon fraction which enters the confined plasma and the fraction which is rapidly driven back

  7. The virtual observatory service TheoSSA: Establishing a database of synthetic stellar flux standards. I. NLTE spectral analysis of the DA-type white dwarf G191-B2B

    Science.gov (United States)

    Rauch, T.; Werner, K.; Bohlin, R.; Kruk, J. W.

    2013-12-01

    Context. Hydrogen-rich, DA-type white dwarfs are particularly suited as primary standard stars for flux calibration. State-of-the-art NLTE models consider opacities of species up to trans-iron elements and provide reliable synthetic stellar-atmosphere spectra to compare with observations. Aims: We will establish a database of theoretical spectra of stellar flux standards that are easily accessible via a web interface. Methods: In the framework of the Virtual Observatory, the German Astrophysical Virtual Observatory developed the registered service TheoSSA. It provides easy access to stellar spectral energy distributions (SEDs) and is intended to ingest SEDs calculated by any model-atmosphere code. In case of the DA white dwarf G191-B2B, we demonstrate that the model reproduces not only its overall continuum shape but also the numerous metal lines exhibited in its ultraviolet spectrum. Results: TheoSSA is in operation and contains presently a variety of SEDs for DA-type white dwarfs. It will be extended in the near future and can host SEDs of all primary and secondary flux standards. The spectral analysis of G191-B2B has shown that our hydrostatic models reproduce the observations best at and log g = 7.60 ± 0.05. We newly identified Fe vi, Ni vi, and Zn iv lines. For the first time, we determined the photospheric zinc abundance with a logarithmic mass fraction of -4.89 (7.5 × solar). The abundances of He (upper limit), C, N, O, Al, Si, O, P, S, Fe, Ni, Ge, and Sn were precisely determined. Upper abundance limits of about 10% solar were derived for Ti, Cr, Mn, and Co. Conclusions: The TheoSSA database of theoretical SEDs of stellar flux standards guarantees that the flux calibration of all astronomical data and cross-calibration between different instruments can be based on the same models and SEDs calculated with different model-atmosphere codes and are easy to compare. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope

  8. Ensaios laboratoriais em segmentação de imagens THEOS de parte do litoral norte paulista como requisito aos mapeamentos regionais de uso da Terra e cobertura vegetal

    Directory of Open Access Journals (Sweden)

    Gilberto Pessanha Ribeiro

    2017-05-01

    Full Text Available De demandas de mapeamento cartográfico temático no contexto do projeto de pesquisa "Aplicação de geotecnologias na orientação do uso da Terra com base nos Impactos das mudanças climáticas globais: sub bacias hidrográficas litorâneas do estado de São Paulo e do estado do Rio de Janeiro", liderada pela Faculdade de Engenharia da UERJ e da colaboração eficaz com o Instituto Geológico do Estado de São Paulo, financiado pela FAPESP e FAPERJ, mapas foram produzidos de uso da Terra e cobertura vegetal, tanto com uso da banda pancromática como multiespectrais do sistema THEOS. Trata-se do sensor acoplado ao satélite tailandês THEOS (Thailand Earth Observation Satellite, que é o primeiro equipamento para observação da Terra naquele país, lançado em 1º de Outubro de 2008 por GISTDA - Geo-Informatics and Space Technology Development Agency. A fim de realizar experimentos de laboratório com imagens desse sistema, optou-se por usá-lo em mapeamento dos municípios costeiros paulistas Caraguatatuba e Ubatuba, e o mesmo foi feito com os municípios fluminenses de Paraty, Angra dos Reis e Mangaratiba. Os resultados deste mapeamento estão disponíveis em www.georeferencial.com.br e são aqui apresentados. Foram empregadas técnicas de processamento digital de imagens com uso dos sistemas SPRING e ENVI, e as escalas cartográficas finais 1/125.000 e 1/10.000, com bandas multi e pan, respectivamente. Serão destacados métodos de segmentação e de classificação supervisionada, com o objetivo de identificação de padrões de uso da Terra e cobertura vegetal. Resultados posteriores serão apresentados em relação ao mapeamento das planícies costeiras em face da explosão populacional e imobiliária de grande valor patrimonial nas zonas costeiras.

  9. Formation of edge transport barrier in the ergodic field layer of helical divertor configuration on the Large Helical Device

    International Nuclear Information System (INIS)

    Toi, K; Ohdachi, S; Watanabe, F; Narihara, K; Morisaki, T; Sakakibara, S; Morita, S; Goto, M; Ida, K; Masuzaki, S; Miyazawa, K; Tanaka, K; Tokuzawa, T; Watanabe, K W; Yoshinuma, M

    2006-01-01

    On the Large Helical Device (LHD), low to high confinement (L-H) transition and edge transport barrier (ETB) formation were observed in the low beta regime ((β dia ) dia ): volume-averaged beta derived from diamagnetic measurement) as well as in relatively high beta regime (>1.5%). In most of ETB plasmas electron density preferentially increases in the edge region without a substantial rise of the edge electron temperature. The ETB zone develops inside the ergodic field layer calculated in the vacuum field. The ETB formation strongly destabilizes edge coherent modes such as m/n = 2/3 or 1/2 (m, n: poloidal and toroidal mode numbers), because the plasma edge region is in the magnetic hill. The ETB is partially destroyed by the combination of these edge MHD modes and ELM-like activities. For a particular experimental condition, the forced generation of a sizable m/n = 1/1 magnetic island near the edge by application of external field perturbations facilitates the L-H transition at a lower electron density and suppresses edge MHD modes and ELM-like activities to lower levels

  10. Experimental study of the topological aspect of the ergodic divertor in Tore-supra tokamak; Etude experimentale des aspects topologiques du divertor ergodique de Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Costanzo, L

    2001-10-01

    The control of power deposition onto plasma facing components in tokamaks is a determining factor for future thermonuclear fusion reactors. Plasma surface interaction can be performed using limiters or divertors. The ergodic divertor installed on Tore Supra is an atypical example of a magnetic divertor. It consists in applying a magnetic perturbation which establishes a particular topology of the plasma in contact with the wall (edge plasma). We carried out dedicated experiments in order to study parallel heat flux which strike the divertor neutralizers. This quantitative and qualitative analysis of heat flux as a function of experimental conditions allows to determine the profiles of power deposition along the neutralizers. The influence of plasma electron density, additional heating, impurities and injected gas was established. An experimental study of the sheath heat transmission factor {gamma} was carried out by correlating measurements made with Langmuir probes and infrared imaging. This study gave rise to a major conclusion: for ohmic discharges with deuterium injection and most of the time with helium, it was experimentally confirmed that {gamma}=7 in agreement with classical sheath theory. However, an increase of this factor with additional power has been shown. Detached plasma, which is an attractive regime in order to reduce the power deposition, requires an optimized control. A new measurement of the detachment onset has been developed. It is based on the variation of heat flux onto the plates derived from infrared measurements. A detachment cartography with the determination of a new 2D 'IR' Degree of Detachment was carried out allowing to locate the zone where the detachment starts. We can apply this concept both to other tokamaks such as JET and ITER. A comparison between the axisymmetric divertor and the ergodic divertor is also presented concerning the power deposition in the two configurations. Low heat flux with the ergodic divertor is a

  11. Two-dimensional distribution of electron temperature in ergodic layer of LHD measured from line intensity ratio of CIV and NeVIII

    International Nuclear Information System (INIS)

    Wang, Erhui; Morita, Shigeru; Goto, Motoshi; Murakami, Izumi; Oishi, Tetsutarou; Dong, Chunfeng

    2013-01-01

    Two-dimensional distribution of impurity lines emitted from ergodic layer with stochastic magnetic field lines in Large Helical Device (LHD) has been observed using a space-resolved extreme ultraviolet (EUV) spectrometer. The two-dimensional electron temperature distribution in the ergodic layer is successfully measured using the line intensity ratio of Li-like NeVIII 2s-3p ( 2 S 1/2 - 2 P 3/2 : 88.09 Å, 2 S 1/2 - 2 P 1/2 : 88.13 Å) to 2p-3s ( 2 P 1/2 - 2 S 1/2 : 102.91 Å, 2 P 3/2 - 2 S 1/2 : 103.09 Å) transitions emitted from radial location near Last Closed Flux Surface (LCFS). The intensity ratio analyzed with ADAS code shows no dependence on the electron density below 10 14 cm -3 . The result indicates a little higher temperature, i.e., 220 eV, in the poloidal location at high-field side near helical coils called O-point compared to the temperature near X-point, i.e., 170 eV. The electron temperature profile is also measured at the edge boundary of ergodic layer using the line intensity ratio of Li-like CIV 2p-3d ( 2 P 1/2 - 2 D 3/2 : 384.03 Å, 2 P 3/2 - 2 D 5/2 : 384.18 Å) to 2p-3s ( 2 P 1/2 - 2 S 1/2 : 419.53 Å, 2 P 3/2 - 2 S 1/2 : 419.71 Å) transitions. The intensity ratios analyzed with CHIANTI, ADAS and T.Kawachi codes show a slightly higher temperature near O-point, i.e., 25 eV for CHIANTI, 21 eV for ADAS and 11 eV for T.Kawachi's codes, compared to the temperature at X-point, i.e., 15 - 21 eV for CHIANTI, 9 - 15 eV for ADAS and 6 - 9 eV for T.Kawachi codes. It suggests that the transport coefficient in the ergodic layer is varied with three-dimensional structure. (author)

  12. Unique Continuation Principle for Spectral Projections of Schrödinger Operators and Optimal Wegner Estimates for Non-ergodic Random Schrödinger Operators

    Science.gov (United States)

    Klein, Abel

    2013-11-01

    We prove a unique continuation principle for spectral projections of Schrödinger operators. We consider a Schrödinger operator H = - Δ + V on , and let H Λ denote its restriction to a finite box Λ with either Dirichlet or periodic boundary condition. We prove unique continuation estimates of the type χ I ( H Λ ) W χ I ( H Λ ) ≥ κ χ I ( H Λ ) with κ > 0 for appropriate potentials W ≥ 0 and intervals I. As an application, we obtain optimal Wegner estimates at all energies for a class of non-ergodic random Schrödinger operators with alloy-type random potentials (‘crooked’ Anderson Hamiltonians). We also prove optimal Wegner estimates at the bottom of the spectrum with the expected dependence on the disorder (the Wegner estimate improves as the disorder increases), a new result even for the usual (ergodic) Anderson Hamiltonian. These estimates are applied to prove localization at high disorder for Anderson Hamiltonians in a fixed interval at the bottom of the spectrum.

  13. Long-time behavior of macroscopic quantum systems. Commentary accompanying the English translation of John von Neumann's 1929 article on the quantum ergodic theorem

    Science.gov (United States)

    Goldstein, S.; Lebowitz, J. L.; Tumulka, R.; Zanghì, N.

    2010-11-01

    The renewed interest in the foundations of quantum statistical mechanics in recent years has led us to study John von Neumann’s 1929 article on the quantum ergodic theorem. We have found this almost forgotten article, which until now has been available only in German, to be a treasure chest, and to be much misunderstood. In it, von Neumann studied the long-time behavior of macroscopic quantum systems. While one of the two theorems announced in his title, the one he calls the “quantum H-theorem”, is actually a much weaker statement than Boltzmann’s classical H-theorem, the other theorem, which he calls the “quantum ergodic theorem”, is a beautiful and very non-trivial result. It expresses a fact we call “normal typicality” and can be summarized as follows: for a “typical” finite family of commuting macroscopic observables, every initial wave function ψ0 from a micro-canonical energy shell so evolves that for most times t in the long run, the joint probability distribution of these observables obtained from ψt is close to their micro-canonical distribution.

  14. Ergodicity of financial indices

    Science.gov (United States)

    Kolesnikov, A. V.; Rühl, T.

    2010-05-01

    We introduce the concept of the ensemble averaging for financial markets. We address the question of equality of ensemble and time averaging in their sequence and investigate if these averagings are equivalent for large amount of equity indices and branches. We start with the model of Gaussian-distributed returns, equal-weighted stocks in each index and absence of correlations within a single day and show that even this oversimplified model captures already the run of the corresponding index reasonably well due to its self-averaging properties. We introduce the concept of the instant cross-sectional volatility and discuss its relation to the ordinary time-resolved counterpart. The role of the cross-sectional volatility for the description of the corresponding index as well as the role of correlations between the single stocks and the role of non-Gaussianity of stock distributions is briefly discussed. Our model reveals quickly and efficiently some anomalies or bubbles in a particular financial market and gives an estimate of how large these effects can be and how quickly they disappear.

  15. Ergodicity breaking and localization

    Science.gov (United States)

    Geneston, Elvis; Tuladhar, Rohisha; Beig, M. T.; Bologna, Mauro; Grigolini, Paolo

    2016-07-01

    We study the joint action of the non-Poisson renewal events (NPR) yielding Continuous-time random walk (CTRW) with index α CTRW to the case where the jumps of the runner are correlated and we argue that the the memory-induced localization requires a refinement of the theoretical perspective about determinism and randomness.

  16. Intervjuu Theo van Leeuweniga / intervjueerinud Peeter Linnap

    Index Scriptorium Estoniae

    Leeuwen, Theo van, 1947-

    2011-01-01

    Hollandi visuaalsemiootik pildist kui keelest, kunstiajaloo ja lingvisti teadmiste ühendamise vajadusest, koostööst Gunther Kressiga, kunstiliste ja mittekunstiliste pildivormide suhetest, PowerPointist kui semiootilisest ja kultuurilisest ressursist

  17. Type Theory, Computation and Interactive Theorem Proving

    Science.gov (United States)

    2015-09-01

    and the mean ergodic theo- rem for uniformly convex Banach spaces ,” Ergodic Theory and Dynamical Systems, 35(4):1009-1027, 2015. [17] Jakob von Raumer...for uniformly convex Banach spaces ," Ergodic Theory and Dynamical Systems, 35(4):1009-1027, 2015. 17) J. Tassarotti, D. Dreyer, and V. Vafeidis...in type theory. Harper and student Kuen-Bang Hou developed a machine-checked proof of the equivalence of group actions and cov- ering spaces in

  18. Regularity of pointwise boundary control systems

    DEFF Research Database (Denmark)

    Pedersen, Michael

    1992-01-01

    We will in these notes address some problems arising in "real-life" control application, namely problems concerning distributional control inputs on the boundary of the spatial domain. We extend the classical variational approach and give easily checkable sufficient conditions for the solutions...

  19. 3-dimensional plasma-boundary-layer simulations in uncompletely ergodized magnetic fields; 3-dimensionale Plasmarandschicht-Simulationen in unvollstaendig ergodisierten Magnetfeldern

    Energy Technology Data Exchange (ETDEWEB)

    Harting, Derek M.

    2008-03-16

    Within this work, a numerical tool, the EMC3/EIRENE code, is presented which solves self-consistently the strongly anisotropic 3D fluid equations for the main plasma (hydrogen) and plasma impurities (e.g. carbon) in an ergodic edge plasma layer. The model equations of the EMC3 code are discussed in detail and essential technical extensions are described and carried out, which enables realistic simulations of the edge plasma at TEXTOR-DED. In course of the simulations for the different base mode configurations of the DED, it turned out that a helical structure of laminar flux tubes (bunch of field-lines with one poloidal turn) is formed by the resonant perturbation field. Due to the dominant parallel streaming to the wall being the loss channel in this helical laminar flux tubes and the perpendicular transport into them being the source channel, the laminar flux tubes act like an extended helical scrape of layer, and thus the density and electron temperature are reduced locally in these flux tubes. Additionally, a promising scenario could be identified in the 3/1 base mode configuration of the DED, where remanent island structures exist near the recycling DED surface. Due to the ionization of the recycled hydrogen atoms in this remanent islands, the density increases strongly in these remanent islands and the electron and ion temperatures are reduced locally. It has been shown that in this case, the recycling is significantly changed and even a local high recycling regime is presumed. Some kinetic corrections on the classical parallel electron heatconductivity and the parallel viscosity of ions were implemented into the EMC3 code. (orig.)

  20. Plasma density control with ergodic divertor on Tore Supra; Controle de la densite du plasma en presence du divertor ergodique dans le tokamak Tore Supra

    Energy Technology Data Exchange (ETDEWEB)

    Meslin, B

    1998-04-30

    Plasma density control on the tokamak Tore Supra is important for the optimization of every experimental scenario dealing with the improvement of plasma performances. Specific conditions are required both in the plasma bulk and at the edge. Within the framework of the present study, a magnetic configuration is used in the e plasma edge of Tore Supra: the ergodic divertor configuration. A magnetic perturbation which is resonant with the permanent field destroys the plasma confinement locally, opening the field lines onto the material components. They aim of the study is the characterization of the edge density in every relevant scenario for Tore Supra. The first part of this work is dedicated to density and temperature measurements by a series of fixed Langmuir probes located at the very edge of the plasma. Thanks to them, density regimes have been put in evidence during experiments where the volume averaged density , an usual control parameter of the plasma, was varied. The analysis of heat and particle transport through the plasma edge region explains the mechanisms leading to those regimes. The essential factor in our analysis is the dependence of the electron conductivity and ionization depth on temperature. While heat conduction governs the heat transport, the edge density varies linearly according to . Below a critical temperature, reached when the ion flux amplification at constant power density is large enough, a parallel temperature gradient appears leading to a density gradient in the opposite direction in order to maintain the pressure constant along the field lines. A high recycling regime is obtained and the edge density varies like {sup 3}. The pressure conservation is no more satisfied during the detachment of the plasma, which is characterized by a high neutral density at low temperatures leading to a ion momentum loss by friction against the neutrals. The edge density drops in those conditions. These regimes are similar

  1. The wilderness wanderings: a theo-liminal pedagogy for mind ...

    African Journals Online (AJOL)

    This article argues that the current economic and political underdevelopment in the majority of African countries is a symptom of a profound metaphysical and intellectual crisis in the African person's imagination and consciousness, a consequence of conceptual alienation wrought about mind colonialism. The process of ...

  2. the wilderness wanderings: a theo-liminal pedagogy for mind ...

    African Journals Online (AJOL)

    coloniality lies at the centre of the making of the modern/colonial ... way, as modern subjects we breathe coloniality all the time and every day” ..... slavery. These scholars demonstrate how the wilderness experience, as a process of liberating the Hebrew mind from Egyptian corruption, was fundamental in the formation of ...

  3. Pointwise asymptotic convergence of solutions for a phase separation model

    Czech Academy of Sciences Publication Activity Database

    Krejčí, Pavel; Zheng, S.

    2006-01-01

    Roč. 16, č. 1 (2006), s. 1-18 ISSN 1078-0947 Institutional research plan: CEZ:AV0Z10190503 Keywords : phase-field system * asymptotic phase separation * energy Subject RIV: BA - General Mathematics Impact factor: 1.087, year: 2006 http://aimsciences.org/journals/pdfs.jsp?paperID=1875&mode=full

  4. Probability, random processes, and ergodic properties

    National Research Council Canada - National Science Library

    Gray, Robert M

    2009-01-01

    ... of the material is familiar stuff for mathematicians, but many of the topics and results had not then previously appeared in books. Several topics still find little mention in the more applied literature, including descriptions of random processes as dynamical systems or flows; general alphabet models including standard spaces, Polish spaces...

  5. Probability, random processes, and ergodic properties

    CERN Document Server

    Gray, Robert M

    2014-01-01

    In this new edition of this classic text, much of the material has been rearranged and revised for pedagogical reasons. Many classic inequalities and proofs are now incorporated into the text, and many citations have been added.

  6. A multicultural murder? The Netherlands struggles with the assassination of Theo van Gogh

    NARCIS (Netherlands)

    Lucardie, Anthonie

    2005-01-01

    Amsterdam, October 2, 2004. About 200,000 Netherlanders demonstrate against the centre-right government’s cutbacks and, especially, its plans to reduce facilities for early retirement. Organized by the trade unions, this is the largest demonstration of trade unionists in Dutch history – a classic

  7. Kijk op en omgaan met IT-risico / door Theo Thiadens c.s.

    NARCIS (Netherlands)

    ir. Sander van Laar; Jacqueline van den Broek; Z.F.M. (Rien) Hamers; G. Koenders; dr. Th.J.G. Thiadens

    2009-01-01

    Anno 2009 is ICT voor onze organisaties van vitaal belang geworden. Optimale inzet van ICT kan de wendbaarheid vergroten, zonder juiste sturingsgegevens is er geen optimale besluitvorming, het kunnen tracen van activiteiten leidt tot minder misbruik. Daarom moet de ICT maximaal en optimaal

  8. Statistical properties of dynamical systems – Simulation and abstract computation

    International Nuclear Information System (INIS)

    Galatolo, Stefano; Hoyrup, Mathieu; Rojas, Cristóbal

    2012-01-01

    Highlights: ► A survey on results about computation and computability on the statistical properties of dynamical systems. ► Computability and non-computability results for invariant measures. ► A short proof for the computability of the convergence speed of ergodic averages. ► A kind of “constructive” version of the pointwise ergodic theorem. - Abstract: We survey an area of recent development, relating dynamics to theoretical computer science. We discuss some aspects of the theoretical simulation and computation of the long term behavior of dynamical systems. We will focus on the statistical limiting behavior and invariant measures. We present a general method allowing the algorithmic approximation at any given accuracy of invariant measures. The method can be applied in many interesting cases, as we shall explain. On the other hand, we exhibit some examples where the algorithmic approximation of invariant measures is not possible. We also explain how it is possible to compute the speed of convergence of ergodic averages (when the system is known exactly) and how this entails the computation of arbitrarily good approximations of points of the space having typical statistical behaviour (a sort of constructive version of the pointwise ergodic theorem).

  9. Gossips and prejudices: ergodic randomized dynamics in social networks

    NARCIS (Netherlands)

    Frasca, Paolo; Ravazzi, Chiara; Tempo, Roberto; Ishii, Hideaki

    In this paper we study a new model of opinion dynamics in social networks, which has two main features. First, agents asynchronously interact in pairs, and these pairs are chosen according to a random process: following recent literature, we refer to this communication model as “gossiping‿. Second,

  10. The Non-Ergodic Nature of Internal Conversion

    DEFF Research Database (Denmark)

    Sølling, Theis I.; Kuhlman, Thomas Scheby; Stephansen, Anne B.

    2014-01-01

    the nonstatistical nature of the excited-state deactivation process is presented. The examples are categorized into four groups. 1) Localization of the energy in one degree of freedom in S2!S1 transitions, in which the transition is either determined by the time spent in the S2!S1 coupling region or by the time...

  11. Ergodic behavior of Markov processes with applications to limit theorems

    CERN Document Server

    Kulik, Alexei

    2017-01-01

    The series is devoted to the publication of monographs and high-level textbooks in mathematics, mathematical methods and their applications. Apart from covering important areas of current interest, a major aim is to make topics of an interdisciplinary nature accessible to the non-specialist. The works in this series are addressed to advanced students and researchers in mathematics and theoretical physics. In addition, it can serve as a guide for lectures and seminars on a graduate level. The series de Gruyter Studies in Mathematics was founded ca. 30 years ago by the late Professor Heinz Bauer and Professor Peter Gabriel with the aim to establish a series of monographs and textbooks of high standard, written by scholars with an international reputation presenting current fields of research in pure and applied mathematics. While the editorial board of the Studies has changed with the years, the aspirations of the Studies are unchanged. In times of rapid growth of mathematical knowledge carefully written monogr...

  12. Bond-Induced Ergodicity Breakdown in Reactive Mixtures

    International Nuclear Information System (INIS)

    Corezzi, S.; Comez, L.; Fioretto, D.; Monaco, G.; Verbeni, R.

    2006-01-01

    We have studied by inelastic x-ray scattering, at wave vectors 1 nm -1 ≤q≤15 nm -1 , the high-frequency dynamics of epoxy-amine mixtures as the monomers irreversibly polymerize. We find that chemical bonding, while inducing molecular ordering on a mesoscopic length scale, also efficiently realizes the mechanism of dynamical arrest described by the mode-coupling theory, as manifested by a cusp singularity in the behavior of the nonergodicity factor as a function of the number of chemical bonds. These results confront positively the mode-coupling theory with a new control parameter

  13. Existence of Bounded Invariant Measures in Ergodic Theory

    Science.gov (United States)

    1967-01-01

    hold: (a) g >0a.s.=X(h) > Oforeveryh eL , h # 0. (b) g = 0 a.s. XX(h) = Ofor at least one h E LX such that h > 0 a.s. PROOF. The class A = {f: f E L...Lx T8-nifo i=0 when j > 0. Hence, the hypothesis lim infnx ( Tifo , h) = 0 made on h, where one may substitute fo by f(o) by the remark of alinea 1...letf = t(1 + E T*nih)-l. Thenf > 0, a.s. andf < t so thatf EL ’ from f(i T*nih) < t follows that f (_ T-nf)h dA < mo. But if (d) is verified, E Tnif

  14. Strong ergodic theorem for commutative semigroup of non ...

    Indian Academy of Sciences (India)

    M Azhini

    2017-08-14

    Aug 14, 2017 ... Chin. Ann. Math. 17 (1996) 726–736. [19] Miyadera I and Kobayasi K, On the asymptotic behavior of almot-orbit of nonlinear contraction semigroups in Banach space, Nonlinear Anal. TMA 6 (1982) 349–356. [20] Moslehian M S, Nikodem K and Popa D, Asymptotic aspect of the quadratic functional equation.

  15. Parametric inference for discretely observed non-ergodic diffusions

    OpenAIRE

    Jacod, Jean

    2006-01-01

    We consider a multidimensional diffusion process [math] whose drift and diffusion coefficients depend respectively on a parameter [math] and [math] . This process is observed at [math] equally spaced times [math] , and [math] denotes the length of the `observation window'. We are interested in estimating [math] and/or [math] . Under suitable smoothness and identifiability conditions, we exhibit estimators [math] and [math] , such that the variables [math] and [math] are tight for [math] and [...

  16. Ergodicity and Phase Transitions and Their Implications for Earthquake Forecasting.

    Science.gov (United States)

    Klein, W.

    2017-12-01

    Forecasting earthquakes or even predicting the statistical distribution of events on a given fault is extremely difficult. One reason for this difficulty is the large number of fault characteristics that can affect the distribution and timing of events. The range of stress transfer, the level of noise, and the nature of the friction force all influence the type of the events and the values of these parameters can vary from fault to fault and also vary with time. In addition, the geometrical structure of the faults and the correlation of events on different faults plays an important role in determining the event size and their distribution. Another reason for the difficulty is that the important fault characteristics are not easily measured. The noise level, fault structure, stress transfer range, and the nature of the friction force are extremely difficult, if not impossible to ascertain. Given this lack of information, one of the most useful approaches to understanding the effect of fault characteristics and the way they interact is to develop and investigate models of faults and fault systems.In this talk I will present results obtained from a series of models of varying abstraction and compare them with data from actual faults. We are able to provide a physical basis for several observed phenomena such as the earthquake cycle, thefact that some faults display Gutenburg-Richter scaling and others do not, and that some faults exhibit quasi-periodic characteristic events and others do not. I will also discuss some surprising results such as the fact that some faults are in thermodynamic equilibrium depending on the stress transfer range and the noise level. An example of an important conclusion that can be drawn from this work is that the statistical distribution of earthquake events can vary from fault to fault and that an indication of an impending large event such as accelerating moment release may be relevant on some faults but not on others.

  17. One-dimensional XY model: Ergodic properties and hydrodynamic limit

    Science.gov (United States)

    Shuhov, A. G.; Suhov, Yu. M.

    1986-11-01

    We prove theorems on convergence to a stationary state in the course of time for the one-dimensional XY model and its generalizations. The key point is the well-known Jordan-Wigner transformation, which maps the XY dynamics onto a group of Bogoliubov transformations on the CAR C *-algebra over Z 1. The role of stationary states for Bogoliubov transformations is played by quasifree states and for the XY model by their inverse images with respect to the Jordan-Wigner transformation. The hydrodynamic limit for the one-dimensional XY model is also considered. By using the Jordan-Wigner transformation one reduces the problem to that of constructing the hydrodynamic limit for the group of Bogoliubov transformations. As a result, we obtain an independent motion of "normal modes," which is described by a hyperbolic linear differential equation of second order. For the XX model this equation reduces to a first-order transfer equation.

  18. Strong ergodic theorem for commutative semigroup of non ...

    Indian Academy of Sciences (India)

    Author Affiliations. M AZHINI1 H M KENARI1 R SAADATI2. Department of Mathematics, Science and Research Branch, Islamic Azad University, Ashrafi Esfahani Ave, Tehran 14778, Iran; Department of Mathematics and Computer Science, Iran University of Science and Technology, Tehran, Iran ...

  19. Generalized Fokker-Planck equation, Brownian motion, and ergodicity.

    Science.gov (United States)

    Plyukhin, A V

    2008-06-01

    Microscopic theory of Brownian motion of a particle of mass M in a bath of molecules of mass mforce, and the generalized Fokker-Planck equation involves derivatives of order higher than 2. These equations are derived from first principles with coefficients expressed in terms of correlation functions of microscopic force on the particle. The coefficients are evaluated explicitly for a generalized Rayleigh model with a finite time of molecule-particle collisions. In the limit of a low-density bath, we recover the results obtained previously for a model with instantaneous binary collisions. In the general case, the equations contain additional corrections, quadratic in bath density, originating from a finite collision time. These corrections survive to order (m/M)2 and are found to make the stationary distribution non-Maxwellian. Some relevant numerical simulations are also presented.

  20. From cutting-edge pointwise cross-section to groupwise reaction rate: A primer

    Science.gov (United States)

    Sublet, Jean-Christophe; Fleming, Michael; Gilbert, Mark R.

    2017-09-01

    The nuclear research and development community has a history of using both integral and differential experiments to support accurate lattice-reactor, nuclear reactor criticality and shielding simulations, as well as verification and validation efforts of cross sections and emitted particle spectra. An important aspect to this type of analysis is the proper consideration of the contribution of the neutron spectrum in its entirety, with correct propagation of uncertainties and standard deviations derived from Monte Carlo simulations, to the local and total uncertainty in the simulated reactions rates (RRs), which usually only apply to one application at a time. This paper identifies deficiencies in the traditional treatment, and discusses correct handling of the RR uncertainty quantification and propagation, including details of the cross section components in the RR uncertainty estimates, which are verified for relevant applications. The methodology that rigorously captures the spectral shift and cross section contributions to the uncertainty in the RR are discussed with quantified examples that demonstrate the importance of the proper treatment of the spectrum profile and cross section contributions to the uncertainty in the RR and subsequent response functions. The recently developed inventory code FISPACT-II, when connected to the processed nuclear data libraries TENDL-2015, ENDF/B-VII.1, JENDL-4.0u or JEFF-3.2, forms an enhanced multi-physics platform providing a wide variety of advanced simulation methods for modelling activation, transmutation, burnup protocols and simulating radiation damage sources terms. The system has extended cutting-edge nuclear data forms, uncertainty quantification and propagation methods, which have been the subject of recent integral and differential, fission, fusion and accelerators validation efforts. The simulation system is used to accurately and predictively probe, understand and underpin a modern and sustainable understanding of the nuclear physics that is so important for many areas of science and technology; advanced fission and fuel systems, magnetic and inertial confinement fusion, high energy, accelerator physics, medical application, isotope production, earth exploration, astrophysics and homeland security.

  1. Pointwise decay of stationary rotational viscous incompressible flows with nonzero velocity at infinity

    Czech Academy of Sciences Publication Activity Database

    Deuring, P.; Kračmar, S.; Nečasová, Šárka

    2013-01-01

    Roč. 255, č. 7 (2013), s. 1576-1606 ISSN 0022-0396 R&D Projects: GA ČR(CZ) GAP201/11/1304 Institutional support: RVO:67985840 Keywords : stationary incompressible Navier-Stokes system * rotating body * fundamental solution Subject RIV: BA - General Mathematics Impact factor: 1.570, year: 2013 http://www.sciencedirect.com/science/article/pii/S0022039613002106

  2. Pointwise decay of stationary rotational viscous incompressible flows with nonzero velocity at infinity

    Czech Academy of Sciences Publication Activity Database

    Deuring, P.; Kračmar, S.; Nečasová, Šárka

    2013-01-01

    Roč. 255, č. 7 (2013), s. 1576-1606 ISSN 0022-0396 R&D Projects: GA ČR(CZ) GAP201/11/1304 Institutional support: RVO:67985840 Keywords : stationary incompressible Navier-Stokes system * rotating body * fundamental solution Subject RIV: BA - General Math ematics Impact factor: 1.570, year: 2013 http://www.sciencedirect.com/science/article/pii/S0022039613002106

  3. A Review of Point-Wise Motion Tracking Algorithms for Fetal Magnetic Resonance Imaging.

    Science.gov (United States)

    Chikop, Shivaprasad; Koulagi, Girish; Kumbara, Ankita; Geethanath, Sairam

    2016-01-01

    We review recent feature-based tracking algorithms as applied to fetal magnetic resonance imaging (MRI). Motion in fetal MRI is an active and challenging area of research, but the challenge can be mitigated by strategies related to patient setup, acquisition, reconstruction, and image processing. We focus on fetal motion correction through methods based on tracking algorithms for registration of slices with similar anatomy in multiple volumes. We describe five motion detection algorithms based on corner detection and region-based methods through pseudocodes, illustrating the results of their application to fetal MRI. We compare the performance of these methods on the basis of error in registration and minimum number of feature points required for registration. Harris, a corner detection method, provides similar error when compared to the other methods and has the lowest number of feature points required at that error level. We do not discuss group-wise methods here. Finally, we attempt to communicate the application of available feature extraction methods to fetal MRI.

  4. A Software module for pointwise calibration of free form objevts and for uncertainty representation

    DEFF Research Database (Denmark)

    Savio, Enrico; Farmer, A.F.; De Chiffre, Leonardo

    . The Centre for Geometrical Metrology (CGM) at the Technical University of Denmark takes care of free form measurements, in collaboration with DIMEG, University of Padova, Italy. The present report describes a software module, MULTICAL, to be used for the calibration of free form objects. The purpose...... of the software is to calculate the uncertainty of free form measurements according to the method described in the draft standard ISO/WD 15530-6....

  5. From cutting-edge pointwise cross-section to groupwise reaction rate: A primer

    Directory of Open Access Journals (Sweden)

    Sublet Jean-Christophe

    2017-01-01

    Full Text Available The nuclear research and development community has a history of using both integral and differential experiments to support accurate lattice-reactor, nuclear reactor criticality and shielding simulations, as well as verification and validation efforts of cross sections and emitted particle spectra. An important aspect to this type of analysis is the proper consideration of the contribution of the neutron spectrum in its entirety, with correct propagation of uncertainties and standard deviations derived from Monte Carlo simulations, to the local and total uncertainty in the simulated reactions rates (RRs, which usually only apply to one application at a time. This paper identifies deficiencies in the traditional treatment, and discusses correct handling of the RR uncertainty quantification and propagation, including details of the cross section components in the RR uncertainty estimates, which are verified for relevant applications. The methodology that rigorously captures the spectral shift and cross section contributions to the uncertainty in the RR are discussed with quantified examples that demonstrate the importance of the proper treatment of the spectrum profile and cross section contributions to the uncertainty in the RR and subsequent response functions. The recently developed inventory code FISPACT-II, when connected to the processed nuclear data libraries TENDL-2015, ENDF/B-VII.1, JENDL-4.0u or JEFF-3.2, forms an enhanced multi-physics platform providing a wide variety of advanced simulation methods for modelling activation, transmutation, burnup protocols and simulating radiation damage sources terms. The system has extended cutting-edge nuclear data forms, uncertainty quantification and propagation methods, which have been the subject of recent integral and differential, fission, fusion and accelerators validation efforts. The simulation system is used to accurately and predictively probe, understand and underpin a modern and sustainable understanding of the nuclear physics that is so important for many areas of science and technology; advanced fission and fuel systems, magnetic and inertial confinement fusion, high energy, accelerator physics, medical application, isotope production, earth exploration, astrophysics and homeland security.

  6. From cutting-edge pointwise cross-section to groupwise reaction rate: A primer

    OpenAIRE

    Sublet Jean-Christophe; Fleming Michael; Gilbert Mark R.

    2017-01-01

    The nuclear research and development community has a history of using both integral and differential experiments to support accurate lattice-reactor, nuclear reactor criticality and shielding simulations, as well as verification and validation efforts of cross sections and emitted particle spectra. An important aspect to this type of analysis is the proper consideration of the contribution of the neutron spectrum in its entirety, with correct propagation of uncertainties and standard deviatio...

  7. The Relaxation of Some Classes of Variational Integrals with Pointwise Continuous-Type Gradient Constraints

    International Nuclear Information System (INIS)

    De Arcangelis, Riccardo; Zappale, Elvira

    2005-01-01

    Relaxation problems for a functional are analyzed. Identity and integral representation results are proved under continuity-type assumptions, together with the description of the common density by means of convexification arguments. Classical relaxation results are extended to the case of the continuous variable dependence, and the non-identity features described in the measurable dependence case are shown to be non-occurring. Proofs are based on the properties of certain limits of multi-functions, and on an approximation result for functions. Results in more general settings are also obtained

  8. Bifurcation for a reaction-diffusion system with unilateral obstacles with pointwise and integral conditions

    Czech Academy of Sciences Publication Activity Database

    Väth, Martin

    2011-01-01

    Roč. 12, č. 2 (2011), s. 817-836 ISSN 1468-1218 R&D Projects: GA AV ČR IAA100190805 Institutional research plan: CEZ:AV0Z10190503 Keywords : global bifurcation * degree * stationary solutions Subject RIV: BA - General Mathematics Impact factor: 2.043, year: 2011 http://www.sciencedirect.com/science/article/pii/S1468121810001951

  9. Evaluation of a pointwise microcirculation assessment method using liquid and multilayered tissue simulating phantoms

    Science.gov (United States)

    Fredriksson, Ingemar; Saager, Rolf B.; Durkin, Anthony J.; Strömberg, Tomas

    2017-11-01

    A fiber-optic probe-based instrument, designed for assessment of parameters related to microcirculation, red blood cell tissue fraction (fRBC), oxygen saturation (S), and speed resolved perfusion, has been evaluated using state-of-the-art tissue phantoms. The probe integrates diffuse reflectance spectroscopy (DRS) at two source-detector separations and laser Doppler flowmetry, using an inverse Monte Carlo method for identifying the parameters of a multilayered tissue model. Here, we characterize the accuracy of the DRS aspect of the instrument using (1) liquid blood phantoms containing yeast and (2) epidermis-dermis mimicking solid-layered phantoms fabricated from polydimethylsiloxane, titanium oxide, hemoglobin, and coffee. The root-mean-square (RMS) deviations for fRBC for the two liquid phantoms were 11% and 5.3%, respectively, and 11% for the solid phantoms with highest hemoglobin signatures. The RMS deviation for S was 5.2% and 2.9%, respectively, for the liquid phantoms, and 2.9% for the solid phantoms. RMS deviation for the reduced scattering coefficient (μs‧), for the solid phantoms was 15% (475 to 850 nm). For the liquid phantoms, the RMS deviation in average vessel diameter (D) was 1 μm. In conclusion, the skin microcirculation parameters fRBC and S, as well as, μs‧ and D are estimated with reasonable accuracy.

  10. Rotational hypersurfaces with $L_r$-pointwise 1-type Gauss map

    Directory of Open Access Journals (Sweden)

    Akram Mohammadpouri

    2018-07-01

    Full Text Available In this paper, we study hypersurfaces in $\\E^{n+1}$ which Gauss map $G$ satisfies the equation $L_rG = f(G + C$ for a smooth function $f$ and a constant vector $C$, where $L_r$ is the linearized operator of the $(r + 1$th mean curvature of the hypersurface, i.e., $L_r(f=tr(P_r\\circ\

  11. PrAising god or singing of Love? from TheoLogicAL To eroTic ...

    African Journals Online (AJOL)

    Against this background, this contribution will argue that the socalled 'literal' — anthropological. — reading, according to which ... which has received renewed attention, especially since the beginning of the twentieth century, and which has rapidly ... on visual arts, Western literature, and music. 3 for an overview, see siegert ...

  12. Harmonic analysis a comprehensive course in analysis, part 3

    CERN Document Server

    Simon, Barry

    2015-01-01

    A Comprehensive Course in Analysis by Poincaré Prize winner Barry Simon is a five-volume set that can serve as a graduate-level analysis textbook with a lot of additional bonus information, including hundreds of problems and numerous notes that extend the text and provide important historical background. Depth and breadth of exposition make this set a valuable reference source for almost all areas of classical analysis. Part 3 returns to the themes of Part 1 by discussing pointwise limits (going beyond the usual focus on the Hardy-Littlewood maximal function by including ergodic theorems and m

  13. From point-wise stress data to a continuous description of the 3D crustal in situ stress state

    Science.gov (United States)

    Heidbach, O.; Ziegler, M.; Reiter, K.; Hergert, T.

    2017-12-01

    The in situ stress is a key parameter for the safe and sustainable management of geo-reservoirs or storage of waste and energy in deep geological repositories. It is also an essential initial condition for thermo-hydro-mechanical (THM) models that investigate man-made induced processes e.g. seismicity due to fluid injection/extraction, reservoir depletion or storage of heat producing high-level radioactive waste. Without a reasonable assumption on the initial stress condition it is not possible to assess if a man-made process is pushing the system into a critical state or not. However, modelling the initial 3D stress state on reservoir scale is challenging since data are hardly available before drilling in the area of interest. This is in particular the case for the stress magnitude data which are a prerequisite for a reliable model calibration. Here, we present a multi-stage 3D geomechani­cal-numerical model approach to estimate for a reservoir-scale volume the 3D in situ stress state. First, we set up a large-scale model which is calibrated by stress data and use the modelled stress field subsequently to calibrate a small-scale model located within the large-scale model. The local model contains a significantly higher resolution representation of the subsurface geometry around boreholes of a projected geothermal power plant. This approach incorporates two models and is an alternative to the required trade-off between resolution, computational cost and calibration data which is inevitable for a single model; an extension to a three-stage approach would be straight forward. We exemplify the two-stage approach for the area around Munich in the German Molasse Basin. The results of the reservoir-scale model are presented in terms of values for slip tendency as a measure for the criticality of fault reactivation. The model results show that variations due to uncertainties in the input data are mainly introduced by the uncertain material properties and missing estimates for the magnitude of the maximum horizontal stress SHmax, needed for a more reliable model calibration. This leads to the conclusion that at this stage the model's reliability depends only on the amount and quality of input data records such as available stress information rather than on the modelling technique itself.

  14. Magnetic field generation by pointwise zero-helicity three-dimensional steady flow of an incompressible electrically conducting fluid

    Science.gov (United States)

    Rasskazov, Andrey; Chertovskih, Roman; Zheligovsky, Vladislav

    2018-04-01

    We introduce six families of three-dimensional space-periodic steady solenoidal flows, whose kinetic helicity density is zero at any point. Four families are analytically defined. Flows in four families have zero helicity spectrum. Sample flows from five families are used to demonstrate numerically that neither zero kinetic helicity density nor zero helicity spectrum prohibit generation of large-scale magnetic field by the two most prominent dynamo mechanisms: the magnetic α -effect and negative eddy diffusivity. Our computations also attest that such flows often generate small-scale field for sufficiently small magnetic molecular diffusivity. These findings indicate that kinetic helicity and helicity spectrum are not the quantities controlling the dynamo properties of a flow regardless of whether scale separation is present or not.

  15. Nonconventional ergodic averages and multiple recurrence for von Neumann dynamical systems

    NARCIS (Netherlands)

    Austin, T.; Eisner, T.; Tao, T.

    2011-01-01

    The Furstenberg recurrence theorem (or equivalently Szemerédi’s theorem) can be formulated in the language of von Neumann algebras as follows: given an integer k ≥ 2, an abelian finite von Neumann algebra (M,τ) with an automorphism α : M→M, and a nonnegative a in M with τ(a) > 0, one has liminf

  16. Subdiffusion and weak ergodicity breaking in the presence of a reactive boundary

    DEFF Research Database (Denmark)

    Lomholt, Michael A; Zaid, Irwin M; Metzler, Ralf

    2007-01-01

    We derive the boundary condition for a subdiffusive particle interacting with a reactive boundary with a finite reaction rate. Molecular crowding conditions, that are found to cause subdiffusion of larger molecules in biological cells, are shown to effect long-tailed distributions with an identical...... regulation by DNA-binding proteins, whose typical concentrations are nanomolar....

  17. Afrika Statistika ISSN 2316-090X On drift estimation for non-ergodic ...

    African Journals Online (AJOL)

    d'indice de Hurst H ∈]1/2, 1[. Le processus {Xt,t ≥ 0} a été observé aux instants t1 = ∆n,...,tn = n∆n, c'est-`a-dire pour tout i ∈ {0, ··· ,n}, ti = i∆n. Nous avons construit deux estimateurs ˆθn et ˇθn de θ fortement consistants, c'est-`a-dire,. ˆθn et ˇθn convergent presque surement vers θ quand n → ∞. Nous avons aussi prouvé ...

  18. Weak Ergodicity Breaking of Receptor Motion in Living Cells Stemming from Random Diffusivity

    Science.gov (United States)

    Manzo, Carlo; Torreno-Pina, Juan A.; Massignan, Pietro; Lapeyre, Gerald J.; Lewenstein, Maciej; Garcia Parajo, Maria F.

    2015-01-01

    Molecular transport in living systems regulates numerous processes underlying biological function. Although many cellular components exhibit anomalous diffusion, only recently has the subdiffusive motion been associated with nonergodic behavior. These findings have stimulated new questions for their implications in statistical mechanics and cell biology. Is nonergodicity a common strategy shared by living systems? Which physical mechanisms generate it? What are its implications for biological function? Here, we use single-particle tracking to demonstrate that the motion of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN), a receptor with unique pathogen-recognition capabilities, reveals nonergodic subdiffusion on living-cell membranes In contrast to previous studies, this behavior is incompatible with transient immobilization, and, therefore, it cannot be interpreted according to continuous-time random-walk theory. We show that the receptor undergoes changes of diffusivity, consistent with the current view of the cell membrane as a highly dynamic and diverse environment. Simulations based on a model of an ordinary random walk in complex media quantitatively reproduce all our observations, pointing toward diffusion heterogeneity as the cause of DC-SIGN behavior. By studying different receptor mutants, we further correlate receptor motion to its molecular structure, thus establishing a strong link between nonergodicity and biological function. These results underscore the role of disorder in cell membranes and its connection with function regulation. Because of its generality, our approach offers a framework to interpret anomalous transport in other complex media where dynamic heterogeneity might play a major role, such as those found, e.g., in soft condensed matter, geology, and ecology.

  19. A general definition of conditional information and its application to ergodic decomposition

    NARCIS (Netherlands)

    L. Debowski (Lukasz Jerzy)

    2009-01-01

    textabstract We discuss a~simple definition of conditional mutual information (CMI) for fields and $\\sigma$-fields. The new definition is applicable also in nonregular cases, unlike the well-known but more restricted definition of CMI by Dobrushin. Certain properties of the two notions

  20. Discrete Moments of Zeta-Functions with respect to random and ergodic transformations

    OpenAIRE

    Srichan, Teerapat

    2015-01-01

    In the thesis discrete moments of the Riemann zeta-function and allied Dirichlet series are studied. In the first part the asymptotic value-distribution of zeta-functions is studied where the samples are taken from a Cauchy random walk on a vertical line inside the critical strip. Building on techniques by Lifshits and Weber analogous results for the Hurwitz zeta-function are derived. Using Atkinson’s dissection this is even generalized to Dirichlet L-functions associated with a primitiv...

  1. Density of the set of symbolic dynamics with all ergodic measures supported on periodic orbits

    OpenAIRE

    Batista, T. C.; Gonschorowski, J. S.; Tal, F. A.

    2014-01-01

    Let $K$ be the Cantor set. We prove that arbitrarily close to a homeomorphism $T:K\\rightarrow K$ there exists a homeomorphism $\\widetilde T:K\\rightarrow K$ such that the $\\alpha$-limit and the $\\omega$-limit of every orbit is a periodic orbit. We also prove that arbitrarily close to an endomorphism $T:K\\rightarrow K$ there exists an endomorphism $\\widetilde T:K\\rightarrow K$ close to $T$ such that every orbit is finally periodic.

  2. Uncovering non-ergodicity on the cell membrane using single particle tracking approaches

    OpenAIRE

    Symeonidou Besi, Parthena

    2013-01-01

    Treball final de màster oficial fet en col·laboració amb Universitat Autònoma de Barcelona (UAB), Universitat de Barcelona (UB) i Institut de Ciències Fotòniques (ICFO) [ANGLES] In this work, we study the diffusion on the plasma membrane of the receptor DC-SIGN. The data we used were obtained by Single Particle Tracking technique and hence consist of individual trajectories. Motivated by investigating the dynamics of this receptor, our analysis comprises not only of standard statistical ap...

  3. Ergodicity of stochastic 2D Navier-Stokes equation with Lévy noise

    Science.gov (United States)

    Dong, Zhao; Xie, Yingchao

    In this paper we deal with the 2D Navier-Stokes equation perturbed by a Lévy noise force whose white noise part is non-degenerate and that the intensity measure of Poisson measure is σ-finite. Existence and uniqueness of invariant measure for this equation is obtained, two main properties of the Markov semigroup associated with this equation are proved. In other words, strong Feller property and irreducibility hold in the same space.

  4. Ergodicity of the Δ3 statistic and purity of neutron resonance data

    International Nuclear Information System (INIS)

    Mulhall, Declan; Huard, Zachary; Zelevinsky, Vladimir

    2007-01-01

    The Δ 3 (L) statistic characterizes the fluctuations of the number of levels as a function of the length of the spectral interval. It is studied as a possible tool to indicate the regular or chaotic nature of the underlying dynamics and to detect missing levels and the mixing of sequences of levels of different symmetry, particularly in neutron resonance data. The relation between the ensemble average and the average over different fragments of a given realization of spectra is considered. A useful expression for the variance of Δ 3 (L) that accounts for finite sample size is discussed. An analysis of neutron resonance data presents the results consistent with a maximum likelihood method applied to the level spacing distribution

  5. Reflectometry measurements during operation of the dynamic ergodic divertor at TEXTOR

    NARCIS (Netherlands)

    Kramer-Flecken, A.; Soldatov, S.; Busch, C.; Liang, Y.; von Hellermann, M.; Wolf, R.; Zimmermann, O.

    2006-01-01

    The O-mode correlation reflectometer at TEXTOR is used for the investigation of the propagation and the properties of the turbulence at the plasma edge. The multi-horn antenna set-up allows the investigation of the correlation properties of the turbulence and its rotation. Turbulence and plasma

  6. Spinodals, scaling, and ergodicity in a threshold model with long-range stress transfer

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, C.D.; Klein, W. [Physics Department, Center for Polymer Physics, and Center for Computational Science, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215 (United States); Rundle, J.B. [Department of Geological Sciences and CIRES, University of Colorado, Boulder, Colorado 80309 (United States)

    1999-08-01

    We present both theoretical and numerical analyses of a cellular automaton version of a slider-block model or threshold model that includes long-range interactions. Theoretically we develop a coarse-grained description in the mean-field (infinite range) limit and discuss the relevance of the metastable state, limit of stability (spinodal), and nucleation to the phenomenology of the model. We also simulate the model and confirm the relevance of the theory for systems with long- but finite-range interactions. Results of particular interest include the existence of Gutenberg-Richter-like scaling consistent with that found on real earthquake fault systems, the association of large events with nucleation near the spinodal, and the result that such systems can be described, in the mean-field limit, with techniques appropriate to systems in equilibrium. {copyright} {ital 1999} {ital The American Physical Society}

  7. Particle dynamics in the rmp ergodic layer under the influence of edge plasma turbulence

    Czech Academy of Sciences Publication Activity Database

    Kurian, M.; Krlín, Ladislav; Cahyna, Pavel; Pánek, Radomír

    2013-01-01

    Roč. 53, č. 4 (2013), s. 359-364 ISSN 1210-2709 R&D Projects: GA AV ČR IAA100430502; GA ČR GA202/07/0044; GA MŠk(CZ) LM2011021 Institutional support: RVO:61389021 Keywords : resonant-magnetic perturbation * plasma turbulence * non-linear dynamics Subject RIV: BL - Plasma and Gas Discharge Physics http://ojs.cvut.cz/ojs/index.php/ap/article/view/1831/1663

  8. ECONOMIC AND FINANCIAL ASPECTS OF ACTIVITY IN S. C. "AL THEO & DEA" S. R. L. - SALCIA COMMON, TELEORMAN COUNTY (2011 – 2013

    Directory of Open Access Journals (Sweden)

    Radu Lucian PÂNZARU

    2014-10-01

    Full Text Available The unit was established in 2006, with the object of "Growing of cereals (except rice, leguminous crops and oil seeds plant" - CAEN code 0111 from 02.08.2006. Formation of the company was based on the association of two persons, Romanian citizens, which constituted a legal entity as a limited liability company. The declared company's office is located in the village of Salcia, County Teleorman, which may establish subsidiaries, as required by law. Life of the society is one unlimited share capital was 200 lei (by 50% for each partner, increase or reduce the capital and its transmission can be achieved in concrete terms stipulated in the articles of established. The company has various equipment (tractors, combines, various machinery, storage, etc. that have experienced an upward trend - both in numbers and in terms of value - during the analyzed period (2011-2013.

  9. Dynamics and stability of rigid rotors levitated by passive cylinder-magnet bearings and driven/supported axially by pointwise contact clutch

    DEFF Research Database (Denmark)

    Andersen, Søren Bøgh; Enemark, Søren; Santos, Ilmar

    2013-01-01

    A stable rotor—supported laterally by passive magnetic bearings and longitudinally by magnetic forces and a clutch—loses suddenly its contact to the clutch and executes abruptly longitudinal movements away from its original equilibrium position as a result of small increases in angular velocity...... contact stability dictated by mechanical–magnetic interaction. Load capacity and stiffness of passive multicylinder magnetic bearings (MCMB) are thoroughly investigated using two theoretical approaches followed by experimental validation. The contact dynamics between the clutch and the rotor supported...... contact to the clutch and (b) an accurate prediction of the threshold of stability based on the nonlinear rotor-bearing model, i.e. maximum angular velocity before the rotor misses its contact to the clutch as a function of rotor, bearing and clutch design parameters....

  10. On the Ergodic Secret-Key Agreement over Spatially Correlated Multiple-Antenna Channels with Public Discussion

    KAUST Repository

    Zorgui, Marwen

    2015-09-28

    We consider secret-key agreement with public discussion over multiple-input multiple-output (MIMO) Rayleigh fast-fading channels under correlated environment. We assume that transmit, legitimate receiver and eavesdropper antennas are correlated. The legitimate receiver and the eavesdropper are assumed to have perfect channel knowledge while the transmitter has only knowledge of the correlation matrices. First, we derive the expression of the secret-key capacity under the considered setup. We prove that the optimal transmit strategy achieving the secret-key capacity consists in transmitting independent Gaussian signals along the eingenvectors of the transmit correlation matrix. The powers allocated to each channel mode are determined as the solution to a numerical optimization problem. A necessary and sufficient condition for beamforming (i.e., transmitting along the strongest channel mode) to be capacity-achieving is derived. Moreover, we analyze the impact of correlation matrices on the system performance. Finally, we study the system’s performance in the two extreme power regimes. In the high-power regime, we provide closed-form expressions of the gain/loss due to correlation. In the low signal-to-noise ratio (SNR) regime, we investigate the energy efficiency of the system by determining the minimum energy required for sharing a secret-key bit and the wideband slope while highlighting the impact of correlation matrices.

  11. O teo-politico na dominação colonial (Theo-politics of colonial domination - DOI: 10.5752/P.2175-5841.2009v7n15p32

    Directory of Open Access Journals (Sweden)

    Eduardo Gusmão de Quadros

    2010-04-01

    Full Text Available Este artigo pretende fundamentar o conceito teo-político na análise do regime colonial estabelecido na conquista da América. Estudando a construção do Padroado na península Ibérica, buscamos identificar como a crença, o poder, a doutrina eclesiástica e o direito civil estão articulados, tanto na Europa quanto no Novo Mundo. Com esse roteiro básico, chegamos ao estudo do Regalismo desenvolvido pelos pensadores ligados ao Estado. Demonstramos ainda que as idéias dos teólogos que pensaram a relação igreja e Estado no século XVIII não eram tão distintas das elaboradas pelo laicato. Essa relação entre o poder e o crer percorre a história humana, mas cremos que conceito de soberania característico da Idade Moderna sobrepõe de modo específico os reinos divino e terrestre. Perceber essas variações dentro da economia teo-política contribui para entender melhor a secularização do Estado no decorrer do século XIX latino-americano e a herança deixada na difícil construção da democracia através do continente.Palavras-chave: Cristandade, Estado, Igreja, Soberania, Crença AbstractThis article explain the concept of teo-political to analysis of the colonial established in conquest of America. Study the construction of Padroado in Iberian Peninsula, seek to identify manners of belief, power, ecclesiastical doctrine and civil law are articulated, in Europe and New World. In this way , we study the Regalismo developed by thinkers linked to the State. Demonstrate that the ideas of theologians who reflecting the relationship between Church and State in the 18th century were not as further than those established by laicato. This relationship between power and believe is presente in human history, but we believe that  modern concept of sovereignty characteristic of Enlightment overlaps specific divine and secular kingdoms. Realize these historical variations  within the teo-political economy contributes to better understand of Secularization of States in the 19th century Latin American and contribute to identify the inheritances in building democratical sistems in this continent.Keywords: Christianity, State, Church, Sovereignty, Beliefs  

  12. ONTO-THEO-LOGY, MYSTICISM AND REVELATION: THE MYSTICAL HERMENEUTICS IN THE LIGHT OF JEAN-LUC MARION AND ITS CONFIRMATION FROM THE CONFRONTATION WITH THE WORKS OF MASTER ECKHART AND MARTIN LUTHER

    OpenAIRE

    ALEXANDRE MARQUES CABRAL

    2016-01-01

    O objetivo central da presente investigação é o de ressignificar o lógos cristão de modo não metafísico. Para dar conta dessa proposta, assumimos a crise das metanarrativas metafísicas caracterizadas por Heidegger como narrativas onto-teo-lógicas. Com a morte de Deus tal qual anunciada por Nietzsche, os supostos ontológicos da ontoteo-logia se deterioraram. Porquanto historicamente a teologia cristã serviu-se das narrativas metafísicas para legitimar seus discursos, torna-se necessário um out...

  13. Theo Van Doesburg y Cornelis Van Eesteren. Tres proyectos para la exposción de la Galería L´Effort Moderne de París

    Directory of Open Access Journals (Sweden)

    María Teresa Escaño Rodríguez

    1998-07-01

    Full Text Available El trabajo que a continuación se presenta tuvo su origen en un estudio preliminar sobre el cromatismo en las casas de van Doesburg y van Eesteren presentadas en la exposición de París de 1923, y realizado por la alumna María Teresa Escaño como ejercicio final del curso de doctorado "La arquitectura de la Nueva Objetividad en Holanda. 1923-1941". Dadoel interés de la misma por el tema y las sugerentes aportaciones que en aquel trabajo original ya se contemplaban, decidimos proseguir en su profundización, completando y precisando aspectos necesitados de mayor desarrollo.

  14. Infinite measure~preserving~transformations with Radon MSJ

    OpenAIRE

    Danilenko, Alexandre I.

    2015-01-01

    We introduce concepts of Radon MSJ and Radon disjointness for infinite Radon measure preserving homeomorphisms of the locally compact Cantor space. We construct an uncountable family of pairwise Radon disjoint infinite Chacon like transformations. Every such transformation is Radon strictly ergodic, totally ergodic, asymmetric (not isomorphic to its inverse), has Radon MSJ and possesses Radon joinings whose ergodic components are not joinings.

  15. Overview of magnetic structure induced by the TEXTOR-DED and the related transport

    International Nuclear Information System (INIS)

    Abdullaev, S.S.; Finken, K.H.; Kobayashi, M.; Reiser, D.; Reiter, D.; Jakubowski, M.W.; Runov, A.M.

    2003-01-01

    The Dynamic Ergodic Divertor (DED), a new concept of the ergodic divertor, is presently installed for the TEXTOR tokamak. Beside the conventional ergodic divertor operation the DED also permits the operation with a rotating magnetic field which allows, in particular, to broaden the heat deposition pattern on the divertor plates. Since its first proposal of the DED in 1996 the structure of magnetic field, especially, the onset of ergodic zone of field lines and related transport in the DED operation has been extensively studied using different theoretical and numerical methods. New methods to study the magnetic field, in particular, the field line mapping have been developed. The presentation gives the overview of the studies on the structure of magnetic field in the DED, the formation of the ergodic and laminar zones of field lines at the plasma edge. It also includes studies on the modelling efforts of the transport of heat and particles in the ergodic and laminar zones. (author)

  16. Capacity bounds for kth best path selection over generalized fading channels

    KAUST Repository

    Hanif, Muhammad Fainan

    2014-02-01

    Exact ergodic capacity calculation for fading wireless channels typically involves time-consuming numerical evaluation of infinite integrals. In this paper, lower and upper bounds on ergodic capacity for kth best path are presented. These bounds have simple analytic expressions which allow their fast evaluation. Numerical results show that the newly proposed bounds closely approximate the exact ergodic capacity for a large variety of system configurations. © 1997-2012 IEEE.

  17. Modeling Single Occupant Vehicle Behavior in High-Occupancy Toll (HOT) Facilities

    Science.gov (United States)

    2009-12-14

    High-occupancy toll (HOT) lanes are in operation, under construction, and planned for in several major metropolitan areas. The premise behind HOT lanes is to allow single occupant vehicles (SOVs) to access high occupancy vehicle (HOV) lanes (and theo...

  18. Diagnostikakeskuse suurosaluse omandas veeäris tegutsenud Janek Ottis / Peeter Raidla

    Index Scriptorium Estoniae

    Raidla, Peeter, 1955-

    2004-01-01

    Tallinna Diagnostikakeskuse aktsiate müügitehingust, keskuses suurosaluse omandanud OÜ Diagnostic Family omaniku Janek Ottise ja keskuse nõukogu liikme Theo Raudsepaga seotud äridest. Vt. samas: Ottis meditsiiniga seotud

  19. Browse Title Index

    African Journals Online (AJOL)

    . R Chih. Vol 23 (2003), The Theos Agnostos: Ismaili and Shaykhi Perspectives, Abstract. A-H Carney. Vol 22 (2002), The Changing Role of the Mallam Intelligentsia During the Colonial Era in Ghana, Abstract. A Iddrisu.

  20. Fluvoxamine

    Science.gov (United States)

    ... perform certain actions over and over) and social anxiety disorder (extreme fear of interacting with others or performing ... Zegerid); other medications for anxiety, depression, or mental illness; phenytoin (Dilantin);sibutramine (Meridia); tacrine (Cognex); theophylline (Theo- ...

  1. SUSTAINABILITY: ECOLOGICAL, SOCIAL, ECONOMIC, TECHNOLOGICAL, AND SYSTEMS ASPECTS

    Science.gov (United States)

    Sustainability is generally associated with a definition by the World Commission on Environment and Development, 1987: "? development that ?meets the needs and aspirations of the present without compromising the ability to meet those of the future' ?" However, a mathematical theo...

  2. Oral bioavailability of slow-release theophylline from unencapsulated beads in preschool children with chronic asthma.

    Science.gov (United States)

    Vaughan, L M; Milavetz, G; Weinberger, M M; Smith, G D; Harris, J B

    1988-01-01

    The relative bioavailability of two slow-release theophylline formulations using bead-filled capsules. Slo-bid and Theo-Dur Sprinkle, was examined in randomized crossover multiple-dose trials using collected saliva. Two groups of seven preschool-age asthmatic children received one of these and Slo-Phyllin Gyrocaps as a reference. Dose-normalized areas under the saliva concentration-time curves were significantly less than the reference for Theo-Dur Sprinkle (p = .02) but not for Slo-bid with the relative bioavailability determinations of 66 +/- 8% (mean +/- SEM) and 109 +/- 5% for Theo-Dur Sprinkle and Slo-bid, respectively. The less complete absorption of Theo-Dur Sprinkle during clinical use in preschool-age children is consistent with the malabsorptive effects of food previously reported for the former but not the latter formulation.

  3. Tapping Diasporas for Development | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2010-10-13

    term development, and keeping volunteers involved after they return,” says Theo Breedon, the CUSO-VSO ... The Global Roundtable of Chief Economists highlights global trends and best practices to help entrepreneurs thrive.

  4. Nonadiabatic quantum wave packet dynamics of the H + H2 reaction ...

    Indian Academy of Sciences (India)

    Administrator

    ; nonadiabatic reaction dyanamics; coriolis coupling. 1. Introduction. The H + H2 → H2 + H exchange reaction has been and still is the cornerstone in the experimental and theo- retical research in the gas phase chemical reaction dynamics. 1.

  5. Medea’s Four Reasons

    Directory of Open Access Journals (Sweden)

    Marco Gemin

    2014-11-01

    Full Text Available The same motivations (eros, logos, bia, theos are attributed by Gorgias to Helen and by Euripides to Medea, which suggests the writers’ common intellectual ground, though the motivations are alternative in Gorgias, simultaneous in Euripides.

  6. Colored chaos

    International Nuclear Information System (INIS)

    Mueller, B.

    1997-01-01

    The report contains viewgraphs on the following: ergodicity and chaos; Hamiltonian dynamics; metric properties; Lyapunov exponents; KS entropy; dynamical realization; lattice formulation; and numerical results

  7. Glass-liquid-glass reentrance in mono-component colloidal dispersions

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez-Gonzalez, P E; Medina-Noyola, M [Instituto de Fisica ' Manuel Sandoval Vallarta' , Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi, SLP (Mexico); Vizcarra-Rendon, A [Unidad Academica de Fisica, Universidad Autonoma de Zacatecas, Paseo la Bufa y Calzada Solidaridad, 98600, Zacatecas, Zac. (Mexico); Guevara-Rodriguez, F de J [Coordinacion de IngenierIa Molecular, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152, 07730 Mexico, DF (Mexico)

    2008-05-21

    The self-consistent generalized Langevin equation (SCGLE) theory of colloid dynamics is employed to describe the ergodic-non-ergodic transition in model mono-disperse colloidal dispersions whose particles interact through hard-sphere plus short-ranged attractive forces. The ergodic-non-ergodic phase diagram in the temperature-concentration state space is determined for the hard-sphere plus attractive Yukawa model within the mean spherical approximation for the static structure factor by solving a remarkably simple equation for the localization length of the colloidal particles. Finite real values of this property signals non-ergodicity and determines the non-ergodic parameters f(k) and f{sub s}(k). The resulting phase diagram for this system, which involves the existence of reentrant (repulsive and attractive) glass states, is compared with the corresponding prediction of mode coupling theory. Although both theories coincide in the general features of this phase diagram, there are also clear qualitative differences. One of the most relevant is the SCGLE prediction that the ergodic-attractive glass transition does not preempt the gas-liquid phase transition, but always intersects the corresponding spinodal curve on its high-concentration side. We also calculate the ergodic-non-ergodic phase diagram for the sticky hard-sphere model to illustrate the dependence of the predicted SCGLE dynamic phase diagram on the choice of one important constituent element of the SCGLE theory.

  8. Cyclic Heating-Annealing and Boltzmann Distribution of Free Energies in a Spin-Glass System

    International Nuclear Information System (INIS)

    Zhou Haijun

    2007-01-01

    Ergodicity of a spin-glass is broken at low temperatures; the system is trapped in one of many ergodic configurational domains. Transitions between different ergodic domains are achievable through a heating-annealing procedure. If this experiment is repeated infinite times, all ergodic configurational domains will be visited with frequences that decreasing exponentially with their free energies. The mean free energy density of a spin-glass system on a random graph is calculated based on this free energy Boltzmann distribution in the present work, by means of the cavity approach.

  9. Colored chaos

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, B.

    1997-09-22

    The report contains viewgraphs on the following: ergodicity and chaos; Hamiltonian dynamics; metric properties; Lyapunov exponents; KS entropy; dynamical realization; lattice formulation; and numerical results.

  10. Psühholoogiline pingpong / Anari Koppel

    Index Scriptorium Estoniae

    Koppel, Anari

    2007-01-01

    PÖFFi filme - islamiäärmuslase poolt mõrvatud hollandi režissööri Theo van Goghi mälestuseks tema 2003.a. linastunud filmi põhjal loodud mängufilm "Intervjuu" ("Interview") : režissöör ja peaosatäitja Steve Buscemi : Ameerika Ühendriigid - Holland 2007. Lisatud selgitav tekst Theo van Goghi kohta

  11. Quantitative metric theory of continued fractions

    Indian Academy of Sciences (India)

    2 (log log n). 1. 2 +ǫ) almost everywhere with respect to the Lebesgue measure. Keywords. Continued fractions; ergodic averages; metric theory of numbers. Mathematics Subject Classification. Primary: 11K50; Secondary: 28D99. 1. Introduction. In this paper, we use a quantitative L2-ergodic theorem to study the metrical ...

  12. Proceedings – Mathematical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    ... mapping from C into itself. In this paper, we prove the strong mean ergodic convergence theorem for the almost-orbit of ℑ . Our results extend and unify many previously known results especially (Dong et al. On the strong ergodic theorem for commutative semigroup of non-Lipschitzian mappings in Banach space, preprint) ...

  13. Logical entropy of quantum dynamical systems

    Directory of Open Access Journals (Sweden)

    Ebrahimzadeh Abolfazl

    2016-01-01

    Full Text Available This paper introduces the concepts of logical entropy and conditional logical entropy of hnite partitions on a quantum logic. Some of their ergodic properties are presented. Also logical entropy of a quantum dynamical system is dehned and ergodic properties of dynamical systems on a quantum logic are investigated. Finally, the version of Kolmogorov-Sinai theorem is proved.

  14. The deviation matrix of a continuous-time Markov chain

    NARCIS (Netherlands)

    Coolen-Schrijner, Pauline; van Doorn, Erik A.

    2002-01-01

    he deviation matrix of an ergodic, continuous-time Markov chain with transition probability matrix $P(.)$ and ergodic matrix $\\Pi$ is the matrix $D \\equiv \\int_0^{\\infty} (P(t)-\\Pi)dt$. We give conditions for $D$ to exist and discuss properties and a representation of $D$. The deviation matrix of a

  15. The deviation matrix of a continuous-time Markov chain

    NARCIS (Netherlands)

    Coolen-Schrijner, P.; van Doorn, E.A.

    2001-01-01

    The deviation matrix of an ergodic, continuous-time Markov chain with transition probability matrix $P(.)$ and ergodic matrix $\\Pi$ is the matrix $D \\equiv \\int_0^{\\infty} (P(t)-\\Pi)dt$. We give conditions for $D$ to exist and discuss properties and a representation of $D$. The deviation matrix of a

  16. A quantum spin system with random interactions I

    Indian Academy of Sciences (India)

    KMS states f&Е3Жg, we report an ergodic property of the spectrum of the generator of the group of unitaries which implement (Е3Ж in the GNS representation. Results pertaining to the ergodic properties of the spectra of random self adjoint operators have also been reported in chapter 1 of [8]. However the techniques used ...

  17. Convolution on spaces of locally summable functions

    Directory of Open Access Journals (Sweden)

    Federica Andreano

    2008-01-01

    Full Text Available In this work we prove the existence of convolution on Marcinkiewicz spaces p(ℝ, 1≤p<∞, and, using pointwise approximate identities, we extend the classical definition of Hilbert transform to such spaces.

  18. Implementation of plot options for the NJOY module DTFR

    International Nuclear Information System (INIS)

    Caldeira, A.D.; Ono, S.

    1989-02-01

    The modifications performed in the DTFR module of NJOY to plot multigroup and pointwise nuclear data and transfer matrices, utilizing the sofware package UNIPLOT in the CDC CYBER 170/750 system, are presented. (author) [pt

  19. Adaptive image interrogation for PIV : Application to compressible flows and interfaces

    NARCIS (Netherlands)

    Theunissen, R.

    2010-01-01

    As an experimental tool, Particle Image Velocimetry has quickly superseded traditional point-wise measurements. The inherent image processing has become standardized though the performances are strongly dependent on user experience. Moreover, the arduously selected image interrogation parameters are

  20. A Laplacian on Metric Measure Spaces

    DEFF Research Database (Denmark)

    Kokkendorff, Simon Lyngby

    2006-01-01

    We introduce a Laplacian on a class of metric measure spaces via a direct pointwise mean value definition. Fundamental properties of this Laplacian, such as its symmetry as an operator on functions satisfying a Neumann or Dirichlet condition, are established.......We introduce a Laplacian on a class of metric measure spaces via a direct pointwise mean value definition. Fundamental properties of this Laplacian, such as its symmetry as an operator on functions satisfying a Neumann or Dirichlet condition, are established....

  1. Theophylline-controlled release preparations and fatty food: an in vitro study using the rotating dialysis cell method.

    Science.gov (United States)

    el-Arini, S K; Shiu, G K; Skelly, J P

    1990-11-01

    The in vitro dissolution behavior of four controlled-release theophylline products was investigated utilizing the rotating dialysis cell method. The effects of pH, oil, and enzymes on the dissolution profiles were studied. The wide range of pH values and the content of oil and enzymes in the dissolution media in the dialysis cell, which functioned as an in vitro model, were simulated to mimic physiological changes due to food along the entire gastrointestinal tract. Treatment with oil affected the dissolution behavior of Uniphyl and especially Theo-Dur Sprinkle but had little or no effect on the dissolution profiles of Theo-Dur tablets and Theo-24 capsules. The in vitro observations of the oil effect were related to the food effect obtained from published in vivo studies. The rotating dialysis cell can be a useful tool in studying factors which may be responsible for dissolution-related food effects on the absorption of controlled-release products.

  2. Pushing the Limits of Kinetic Arts: Strandbeests

    KAUST Repository

    Jansen, Theo

    2017-01-12

    In 1990, Dutch artist Theo Jansen introduced the world to his newest creation, the strandbeests. Kenetic sculptures created from plastic tubing, water bottles, and pipes, these beests survive on their own. These herds live on beaches all around the world, surviving on their waterfeelers and sandfeelers to remain safely on the sand. Powered by wind, these new life forms do not require food! Join us for a keynote lecture with Theo as he discusses the story behind the strandbeests as he pushes the limits with these beautiful and unique animals.

  3. Õhtu kahele / Jaanus Noormets

    Index Scriptorium Estoniae

    Noormets, Jaanus

    2008-01-01

    Islamiäärmuslase poolt mõrvatud hollandi režissööri Theo van Goghi mälestuseks tema 2003.a. linastunud filmi põhjal loodud mängufilm "Intervjuu" ("Interview") : režissöör ja peaosatäitja Steve Buscemi : Ameerika Ühendriigid - Holland 2007. Theo van Goghi "Pimekohtingu" (1996) uusversiooni "Blind Date" (2007) tegi Stanley Tucci ning John Turturrol valmib "1-900" 1994.a. filmi "06" põhjal

  4. Deterministic chaos

    CERN Document Server

    Eckmann, Jean-Pierre

    1999-01-01

    In these lectures, I will give an overview of the mathematical and physical aspects of deterministic chaotic systems. Starting from simple examples, I plan to cover some crucial notions of the theory such as : Hyperbolicity, shadowing and ergodic properties.

  5. A single-server queue with random accumulation level

    Directory of Open Access Journals (Sweden)

    Jewgeni H. Dshalalow

    1991-01-01

    The author establishes an ergodicity criterion for both the queueing process with continuous time parameter and the imbedded process. Under this criterion, the author obtains explicit formulas for the stationary distributions of both processes by using semi-regenerative techniques.

  6. Asymptotic results for the semi-Markovian random walk with delay

    International Nuclear Information System (INIS)

    Khaniyev, T.A.; Aliyev, R.T.

    2006-12-01

    In this study, the semi-Markovian random walk with a discrete interference of chance (X(t) ) is considered and under some weak assumptions the ergodicity of this process is discussed. Characteristic function of the ergodic distribution of X(t) is expressed by means of the probability characteristics of the boundary functionals (N,S N ). Some exact formulas for first and second moments of ergodic distribution of the process X(t) are obtained when the random variable ζ 1 - s, which is describing a discrete interference of chance, has Gamma distribution on the interval [0, ∞) with parameter (α,λ) . Based on these results, the asymptotic expansions with three terms for the first two moments of the ergodic distribution of the process X(t) are obtained, as λ → 0. (author)

  7. Ghosh, Prof. Anish

    Indian Academy of Sciences (India)

    Brandeis). Date of birth: 25 December 1979. Specialization: Ergodic Theory, Lie Groups, Number Theory Address: School of Mathematics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, Maharashtra Contact:

  8. Quadratic Forms on Complex Random Matrices and Multi-Antenna Channel Capacity

    National Research Council Canada - National Science Library

    Ratnarajah, Tharmalingam; Vaillancourt, R

    2004-01-01

    .... The derived densities are used to evaluate the most important information-theoretic measures the so-called ergodic channel capacity and capacity versus outage of multiple-input multiple-output (MIMO...

  9. Frobenius theory for positive maps of von Neumann algebras

    International Nuclear Information System (INIS)

    Albeverio, S.; Hoegh-Krohn, R.

    1978-01-01

    Frobenius theory about the cyclic structure of eigenvalues of irreducible non negative matrices is extended to the case of positive linear maps of von Neumann algebras. Semigroups of such maps and ergodic properties are also considered. (orig.) [de

  10. Multiplicative formulation of quantum mechanics

    International Nuclear Information System (INIS)

    Voros, A.; Leboeuf, P.

    1991-01-01

    A general semi-classical description for the eigenfunctions of the multidimensional Schroedinger operator cannot be based on the WKB method which is incompatible with classically ergodic behavior. An alternative, more general multiplicative parametrization of quantum wave functions is suggested, whereby the semi-classical behavior of eigenfunctions can be traced in the presence of classical ergodicity, in the form of diffusive patterns of phase-space zeros in the quantum wave functions. (author) 24 refs.; 4 figs

  11. Large deviations in physics the legacy of the law of large numbers

    CERN Document Server

    Cecconi, Fabio; Cencini, Massimo; Puglisi, Andrea; Vergni, Davide

    2014-01-01

    This book reviews the basic ideas of the Law of Large Numbers with its consequences to the deterministic world and the issue of ergodicity. Applications of Large Deviations and their outcomes to Physics are surveyed. The book covers topics encompassing ergodicity and its breaking and the modern applications of Large deviations to equilibrium and non-equilibrium statistical physics, disordered and chaotic systems, and turbulence.

  12. New-consensus macroeconomic governance in a Keynesian world, and the Keynesian alternative

    Directory of Open Access Journals (Sweden)

    Angel Asensio

    2006-12-01

    Full Text Available The paper presents both the New Consensus and Keynesian equilibrium within the usual four competitive macro-markets structure. It gives theoretical explanations of the pernicious effects that the NCM governance, which has been designed for ergodic stationary regimes, brings about in Keynesian non-ergodic regimes. It put forward Keynesian principles of governance which include monetary, budgetary and fiscal instruments, and suggest new directions for the positive and normative analysis of macro-policies.

  13. Cellular automata with voting rule

    International Nuclear Information System (INIS)

    Makowiec, D.

    1996-01-01

    The chosen local interaction - the voting (majority) rule applied to the square lattice is known to cause the non ergodic cellular automata behaviour. Presented computer simulation results verify two cases of non ergodicity. The first one is implicated by the noise introduced to the local interactions and the second one follows properties of the initial lattice configuration selected at random. For the simplified voting rule - non symmetric voting, the critical behaviour has been explained rigorously. (author)

  14. Are Children's Views of the "Enemy" Shaped by a Highly-Publicized Negative Event?

    Science.gov (United States)

    Oppenheimer, Louis

    2010-01-01

    In the beginning of the first decade of this century, some highly-publicized extremistic acts of terror occurred. A hostage tragedy in a school in Beslan (North Ossetia) was followed in the Netherlands by the brutal murder of the controversial Dutch filmmaker and newspaper columnist Theo van Gogh, bomb attacks in Bali and Madrid and other acts of…

  15. Einstein as Armchair Detective: The Case of Stimulated Radiation

    Indian Academy of Sciences (India)

    already finished most of his work on the relativity theo- ries. He had earlier done his doctoral thesis on Brownian motion and was a pioneer of what is now called statisti- cal mechanics. He was thus a master at using thermody- namic arguments. He was one of the earliest scientists to accept Planck's radiation law and its light ...

  16. Meie avangardismi löögirühm / Jüri Hain

    Index Scriptorium Estoniae

    Hain, Jüri, 1941-

    2005-01-01

    Näitus "Eesti Kunstnikkude Ryhm" Tartu Kunstimuuseumis 21. I-20. III. 1923. a. lõpul asutatud rühmitusest, EKRi näitusetegevusest, 1928. a. ilmunud almanahhist "Uue Kunsti Raamat" (kujundaja Märt Laarman), mille kohta ajakirjas "Die Form" ilmus Theo van Doesburgi artikkel "Raamat ja selle kujundus"

  17. Mountain Risks: From Prediction to Management and Governance

    Directory of Open Access Journals (Sweden)

    David Petley

    2015-05-01

    Full Text Available Reviewed: Mountain Risks: From Prediction to Management and Governance. Edited by Theo Van Asch, Jordi Corominas, Stefan Greiving, Jean-Philippe Malet, and Sterlacchini Simone. Dordrecht, The Netherlands: Springer, 2014. xi + 413 pp. US$ 129.00, € 90.00, € 104.00. Also available as an e-book. ISBN 978-94-007-6768-3.

  18. Observability of the effects of curl-free magnetic vector potential on ...

    Indian Academy of Sciences (India)

    accepted conceptual framework which does not admit, as per the Lorentz equa- tion, any effect that a curl-free vector potential could have on the dynamics of a charged particle on the macroscale, and hence its detection. Such an observation has been predicted by a formalism developed by the author in a series of theo-.

  19. Maintaining International Peace and Security: Reflections on Peace ...

    African Journals Online (AJOL)

    Maintaining International Peace and Security: Reflections on Peace-Support Operations in Africa. DR THEO NEETHLING. Centrefor Military Studies, University of Stellenbosch. ABSTRACT. The shift from a bipolar to a multipolar and multi-faceted world has reduced the risk of conventional inter-state wars, but has been the ...

  20. Pfister involutions

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    defined [Dej95]. Nevertheless, in view of the fundamental role played by Pfister forms in the theory of quadratic forms, and also of the nice properties they share, it seems ... C(q) its Clifford algebra (see [Sch85] or [Lam73] for a definition and structure theo- ...... SSSR 261(3) (1981) 542–547; English translation: Soviet Math.

  1. The Liberal Struggle for Press Freedom

    DEFF Research Database (Denmark)

    Mogensen, Kirsten

    In this paper, the public debate following the religion-motivated assassination of Dutch filmmaker Theo van Gogh in November 2004 is examined. The paper aims at describing religious as well as secular positions in the Danish debate about freedom of speech and press in relation to religious issues...

  2. Interactive Theorem Proving and Verification

    Indian Academy of Sciences (India)

    The goal of Auto- mated Theorem Proving, as the name suggests, is to try to prove a wide range of mathematical theorems using a computer in an automatic fashion. On the other hand, Interactive Theo- rem Proving tries to achieve similar goals, but in the form of a collaborative effort between human beings and computers.

  3. Decoding Codes on Graphs

    Indian Academy of Sciences (India)

    set up a well defined goal - that of achieving a per- formance bound set by the noisy channel coding theo- rem, proved in the paper. Whereas the goal appeared elusive twenty five years ago, today, there are practi- cal codes and decoding algorithms that come close to achieving it. It is interesting to note that all known.

  4. JPRS Report; Science & Technology Japan.

    Science.gov (United States)

    1989-05-02

    section of a capacitor , shown in Figure 1 (B), cut using a precision low-speed cutting device to reveal the location of the spacer section. The...o o o Magnetic abrasives o o Magnetic fluid o Magnetic fluid / 113 <Magnetic Polishing Using a Magnetic Fluid> S.S. Papel of the United

  5. Dielectric relaxation of ethanol and N-methyl acetamide polar ...

    Indian Academy of Sciences (India)

    ... temperatures except at 35°C. This signifies the validity of both the proposed methods in estimating and . The molecular dynamics of the polar mixture are ascertained from Eyring rate theory. Theoretical dipole moments from bond angles and bond moments ( theo ) are also calculated to predict associational aspects.

  6. Elastic constants and Debye temperature of wz-AlN and wz-GaN ...

    Indian Academy of Sciences (India)

    2014-09-05

    Sep 5, 2014 ... B P Pandey, V Kumar and Eduardo Menendez Proupin varying the wide band gap [4,5]. These two are also very prominent binary compounds in extreme conditions of high pressure and temperature. Therefore, experimental and theo- retical investigations are of great interest to physicists and researchers.

  7. Generalized entropy production fluctuation theorems for quantum ...

    Indian Academy of Sciences (India)

    The inequality of second law of thermodynamics gets modified in the presence of informa- tion. These FTs are robust ... Nonequlibrium processes are common in nature, but a general framework to understand them is lacking as ... possibility of transient violations of second law for individual realization [9]. These theo-.

  8. Segaduses Holland kisub äärmusse / Jeroen Bult

    Index Scriptorium Estoniae

    Bult, Jeroen

    2005-01-01

    Olukorrast Hollandis: aasta pärast filmirežissöör Theo van Goghi traagilist surma on riik ikka veel haaratud terrorismirünnakute kartusest. Riigi poliitikast sisserändajate suhtes. Vt. samas: Kuninganna kiitis Putinit võitluses terrorismiga

  9. APPLICATION OF ELASTICITY ANALYSES AND PERTURBATION SIMULATIONS IN DETERMINING STRESSOR IMPACTS ON POPULATION GROWTH RATE AND EXTINCTION RISK

    Science.gov (United States)

    Population structure and life history strategies are determinants of how populations respond to stressor-induced impairments in individual-level responses, but a consistent and holistic analysis has not been reported. Effects on population growth rate were modeled using five theo...

  10. 14. IX avati VI Tallinna arhitektuuritriennaali raames tarbekunsti- ja disainimuuseumi trepikojas...

    Index Scriptorium Estoniae

    2005-01-01

    Londoni Architectural Association School of Architecture üliõpilaste tööde näitus. Juhendajad: Miraj Ahmed, Theo Lorenz, Saskia Lewis, Benedict O'Looney. Väljapanek on Victoria ja Alberti muuseumi, Royal Institute of British Architects (RIBA) ja Eesti Kunstiakadeemia arhitektuuriteaduskonna koostöö

  11. Het bevel 'persoonlijk verschijnen' en de last 'medebrenging' voor het aanhoren van een uitspraak in strafzaken. Naar aanleiding van Mohammed B

    NARCIS (Netherlands)

    van Laanen, F.

    2005-01-01

    Op 21 juli 2005 werd in de media bericht dat de Rechtbank Amsterdam de verdachte Mohammed B. zou dwingen tot het aanhoren van de uitspraak in de strafzaak die tegen hem werd gevoerd, onder meer betreffende de moord op Theo van Gogh. De verdachte was al eerder verplicht om te verschijnen bij het

  12. Comparative study of spectroscopic properties of the low-lying ...

    Indian Academy of Sciences (India)

    due to the substitutions by methyl (II), isopropyl (III) and fluoromethyl (IV) groups on nitrogen. Some theo- retical studies on PSB (I) have been earlier reported at different level of calculations. AM1/CISD, MP4, MRCI calculations have been carried out by Dobado and. Nonella,25 while MNDO-CI method has been applied.

  13. Fulltext PDF

    Indian Academy of Sciences (India)

    coriolis coupling between the different electronic states. In fact, the Renner-Teller effect arises due to breakdown of the Born-Oppenheimer approximation. Several theo- retical developments have been reported on this effect for linear triatomic and tetraatomic molecules. For details, see references8,9 and references therein.

  14. Variations in first principles calculated defect energies in GaAs and ...

    Indian Academy of Sciences (India)

    functional theory and first principles non-local pseudo- potential of the same type as Jansen and Sankey. In both these calculations, however, relaxations were not included. It is important to relax the ions while performing elec- tronic structure calculations. There have been such theo- retical studies using tight binding (TB) ...

  15. A unified view on Aharanov–Bohm like phases and some applications

    Indian Academy of Sciences (India)

    Apart from imparting elegance and beauty to the theo- ... The standard A–B effect happens to be discussed in a situation where this interaction energy is independent of the spatial position of the test charge with respect to the currents. The essential .... physical origin and properties of the standard Aharanov–Bohm effect.

  16. Round table discussion at the workshop "New directions in modern cosmology"

    NARCIS (Netherlands)

    Nieuwenhuizen, T.M.; Keefe, P.D.; Spicka, V.

    2011-01-01

    The workshop "New directions in modern cosmology", organized by Theo Nieuwenhuizen, Rudy Schild, Francesco Sylos Labini and Ruth Durrer, was held from September 27 until October 1, 2010, in the Lorentz Center in Leiden, the Netherlands. A transcript of the final round table discussion, chaired by

  17. 05 Human 03.pmd

    African Journals Online (AJOL)

    Owner

    24 Jul 2008 ... Karolina Ferreira (translated as The Elusive Moth, 1993, 2005), Jan de Dood in Buller se plan (Buller's plan, 1999) and Theo. Verwey in Die ..... Uit die eerste hoofstuk van Die boek van toeval en toeverlaat blyk dit dat Helena Ver- ..... Na die oorlog trou hy met Niggie (aangesien sy 'n goeie ma vir sy enigste.

  18. BOOK M:ANAGER'S CHOICE

    African Journals Online (AJOL)

    DESIGN AND IMPLEMENTATION. OF HEALTH INFORMATION. SYSTEMS*. Edited by Theo L£ppeveld, Rainer SauerboTn, Claude Bodart. Pp. xi +270. Sw.fr. 70/US/63. WHO. 2000. ISBN 92-4-156199-8. Information systems are fundamental to any health system. This is true whether the information is required to monitor ...

  19. Fulltext PDF

    Indian Academy of Sciences (India)

    (API) and electronic industry.11–20 Also, several theo- retical studies have been performed on these structural molecules.21–26. In this paper research, we report the synthesis and characterization of two novel cocrystals, [(DABTZ). ∗For correspondence. (bpo)] (1) and [(DABTZ) (bpa)] (2) by elemental and thermal analysis ...

  20. Staarielu kui teater / Mathura

    Index Scriptorium Estoniae

    Mathura, pseud., 1973-

    2008-01-01

    Režissöör Theo van Goghi mälestuseks tema 2003.a. linastunud filmi põhjal loodud mängufilm "Intervjuu" ("Interview") : režissöör ja peaosatäitja Steve Buscemi : Ameerika Ühendriigid - Holland 2007

  1. Näitemäng stereotüüpidega / Rivo Sarapik

    Index Scriptorium Estoniae

    Sarapik, Rivo, 1981-

    2008-01-01

    Režissöör Theo van Goghi mälestuseks tema 2003.a. linastunud filmi põhjal loodud mängufilm "Intervjuu" ("Interview") : režissöör ja peaosatäitja Steve Buscemi : Ameerika Ühendriigid - Holland 2007

  2. Are children's views of the "enemy" shaped by a highly-publicized negative event?

    NARCIS (Netherlands)

    Oppenheimer, L.

    2010-01-01

    In the beginning of the first decade of this century, some highly-publicized extremistic acts of terror occurred. A hostage tragedy in a school in Beslan (North Ossetia) was followed in the Netherlands by the brutal murder of the controversial Dutch filmmaker and newspaper columnist Theo van Gogh,

  3. On optimal designing of low frequency polychromatic fields for facile ...

    Indian Academy of Sciences (India)

    Administrator

    experimental attention in the recent years. The theo- retical interest primarily stems from the fact that the interaction between matter and radiation in strong field regimes poses questions that are yet to be an- swered fully. On the experimental front the problem of realizing appropriate laser intensity, frequency, pulse shape ...

  4. Fulltext PDF

    Indian Academy of Sciences (India)

    E-mail: niloofar.zoghi@gmail.com. MS received 3 May 2016; revised 28 August 2016; accepted 27 October 2016; published online 22 March 2017. Abstract. In this article, the cluster–cluster interaction between α-clusters in 16O and 20Ne is studied theo- retically. Using the generalized Nikiforov–Uvarov (NU) technique, the ...

  5. The gravity dual of the non-perturbative V = 2 supersymmetric Yang ...

    Indian Academy of Sciences (India)

    -Mills theory. sATCHIDANANDA NAIK. Harish-Chandra Research Institute, Jhusi, Allahabad 211 019, India. Abstract. The anomalous Ward identity is derived for V = 2 SUSY Yang-Mills theo- ries, which is resulted out of wrapping of D5 branes ...

  6. Targalt tehtud ja loovalt rakendatud / Ülle Jehe, Ville Jehe, Ele Praks

    Index Scriptorium Estoniae

    Jehe, Ülle

    2007-01-01

    Ülle ja Ville Jehe meelisasju disainivallas - interaktiivsed padjad rootsi tudengitelt, perfektse relvadisaini näidisena jaapani mõõk katana, ameeriklaste Charles ja Ray Eamesi 1946. aastal disainitud kehakontuure jälgiv tool ja Theo Janseni kineetilised, tuule jõul liikuvad skulptuurid

  7. Islamofobie en discriminatie

    NARCIS (Netherlands)

    Valk, Ineke van der

    2012-01-01

    Since 11 September 2001 – and especially since the murder of Theo van Gogh – Muslims and Islam have frequently been unfavourably portrayed at the heart of public debate. Manifestations of Islamophobia can be found on the Internet, in comments by the PVV, and in acts of violence committed against

  8. Browse Title Index

    African Journals Online (AJOL)

    Items 451 - 500 of 669 ... Vol 42, No 4 (2013), South Africa in the BRICS: Opportunities, Challenges and Prospects1, Abstract. H Besada, E Tok, K Winters. Vol 32, No 4 (2002), South Africa's military potency - too lean or too mean? Abstract. Theo Neethling. Vol 43, No 2 (2013), South Africa's SAFARI From nuclear weapons to ...

  9. Fulltext PDF

    Indian Academy of Sciences (India)

    The theory of g-inverses has seen a substantial growth over the past few decades. It is an area of great theo- retical interest which finds applications in many diverse areas, including statistics, numerical analysis, Markov chains, differential equations and control theory. What is the motivation for seeking a generalized no-.

  10. Next-to-next-leading order correction to 3-jet rate and event-shape ...

    Indian Academy of Sciences (India)

    The coupling constant, , was measured by two different methods: first by employing the three-jet observables. Combining all the data, the value of as at next-to-next leading order (NNLO) was determined to be 0.117 ± 0.004(hard) ± 0.006(theo). Secondly, from the event-shape distributions, the strong coupling constant, ...

  11. Die boek van toeval en toeverlaat (Ingrid Winterbach): 'n ...

    African Journals Online (AJOL)

    The main character, Helena Verbloem, goes on a journey of discovery: to find her stolen shells, and to determine what role chance and contingency plays in man's search for meaning and order. On both these journeys she is accompanied by her colleague Sof Benadé and to a certain extent her employer, Theo Verwey.

  12. Fulltext PDF

    Indian Academy of Sciences (India)

    realization of their potential. It was no easy task convincing Raymond to hold this meeting, as he has often shunned laurels and the limelight. Fortunately, the prospect of seeing old friends and reviving part of the history of the construction of gauge theo- ries in front of younger generations, and then having a garden party did ...

  13. Description of travel behaviour in the traffic model - a critical review

    DEFF Research Database (Denmark)

    Nielsen, Otto Anker

    I de sidste år har der været en diskussion af trafikmodellers behandling af trafikanters rejse-adfærd. I Danmark har blandt andre forfatteren bidraget til dis-kussionen, mens Gärling (1994) har været med til at starte den internationale dis-kussion, der blandt andet mundede ud i konferencen "Theo...

  14. The Liberal Struggle for Press Freedom

    DEFF Research Database (Denmark)

    Mogensen, Kirsten

    In this paper, the public debate following the re-ligion-motivated assassination of Dutch filmmaker Theo van Gogh in November 2004 is examined. The paper aims at describ-ing religious as well as secular positions in the Danish debate about freedom of speech and press in relation to religious issu...

  15. Relaxation phenomena of polar non-polar liquid mixtures under low ...

    Indian Academy of Sciences (India)

    The hf s in Coulomb metre (C m) when compared with static and reported s indicate that ss favour the monomer formations which combine to form dimers in the hf electric field. The comparison among s shows that a part of the molecule is rotating under X-band electric field [5]. The theoretical theos from available ...

  16. Korgipuu uued viljad / Tõnis Malkov

    Index Scriptorium Estoniae

    Malkov, Tõnis

    2008-01-01

    Rahvusvaheline ehtekunsti rändnäitus "2nd SKIN. Korgipuust ehted" Eesti Tarbekunsti- ja Disainimuuseumis. Eestist osalevad Kadri Mälk, Tanel Veenre. Kunstnike Carla Castiajo, Leonor Hipolito, Ramon Puig Cuyase, Eija Mustoneni, Theo Smeetsi, Manuel Vilhena, Pedro Segueira töödest

  17. the education of visually handicapped children, with special ...

    African Journals Online (AJOL)

    1971-04-10

    Apr 10, 1971 ... THE EDUCATION OF VISUALLY HANDICAPPED CHILDREN, WITH SPECIAL. REFERENCE TO THE WORCESTER SCHOOL FOR THE BLIND. THEO PAUW, Principal, School for the Blind, Worcester, CP. I welcome this opportunity to write on a topic which .deals with a group of children who are our ...

  18. Deciduous Forest Zone of Ghana

    African Journals Online (AJOL)

    The semi-deciduous forest Zone of Ghana contains some of the most productive soils of the country (Ahn, 1970; Adu, 1992). The. Zone, which covers some 48,000 km, has adequate rainfall for the cultivation of large. Scale plantation crops, such as cocoa Theo- broma cacao, oil palm (Elaeisguineensis) and lemon (Citrus ...

  19. Pramana – Journal of Physics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The hf s in Coulomb metre (C m) when compared with static and reported s indicate that ss favour the monomer formations which combine to form dimers in the hf electric field. The comparison among s shows that a part of the molecule is rotating under X-band electric field [5]. The theoretical theos from available ...

  20. Pimedate ööde festival ulatub teatrikinno / Jaanus Kaasik

    Index Scriptorium Estoniae

    Kaasik, Jaanus

    2004-01-01

    Rakvere Teatrikinos näidatavatest filmidest : noortefilmid "Terkel jamas", režissöör Stefan Fjeldmark, "Cool", režissöör Theo van Gogh; filmid "Sisemeri", režissöör Alejandro Amenabar ja "Nikotiin", režissöör Hugo Rodriguez

  1. Ekumeniese speelbal of reformatories teologiese noodsaaklikheid

    African Journals Online (AJOL)

    language, has as goal to show that this impasse can be solved. If theo logical language uses models in its discussions, any talk about filioque will be open to more than one interpretation. Filioque ..... Aangesien die saak oop is vir bespreking en daar persone is wat sterk voel vir die behoud van die filioque en ook persone is ...

  2. A proof-theoretic account of the miners paradox

    Czech Academy of Sciences Publication Activity Database

    Klev, Ansten

    2016-01-01

    Roč. 82, č. 4 (2016), s. 351-369 ISSN 1755-2567 Institutional support: RVO:67985955 Keywords : miners paradox * proof theory * Ramsey conditionals * Fitch's Paradox Subject RIV: AA - Philosophy ; Religion http://onlinelibrary.wiley.com/doi/10.1111/theo.12090/full

  3. Neue Generation, neue Medien und eine neue Bildung?

    NARCIS (Netherlands)

    Bastiaens, Theo; Schrader, Claudia

    2018-01-01

    Extract Neue Generation, neue Medien und eine neue Bildung? Theo Bastiaens & Claudia Schrader Abstract This chapter focuses on the question of what influence societal changes have on learners, their learning behavior and the curriculum. Fact is that there has been one major change with an

  4. Coteaching, Peer Tutoring and Curriculum Writing: Lasting Effects of Involving Students in Talking about Science

    Science.gov (United States)

    Bayne, Gillian U.

    2013-01-01

    This article presents the findings of a 3-year case study that examines the lasting effects of having participated in cogenerative dialogues during a 9th grade science experience. Theo, a high school student researcher of more than three years, affords insights into the expansion of human agency, attributing it to his consistent participation in…

  5. Didactics of mathematics as a scientific discipline

    National Research Council Canada - National Science Library

    Biehler, Rolf

    1994-01-01

    ... knowledge Rainer Bromme 73 Dialogue between theory and practice in mathematics education Heinz Steinbring 89 On the application of science to teaching and teacher education Thomas J. Cooney 103 3. INTERACTION IN THE CLASSROOM Introduction Rudolf Sträßer 117 Theoretical and empirical approaches to classroom interaction Maria G. Bartolini Bussi 121 Theo...

  6. 'We were not part of apartheid': rationalisations used by four white ...

    African Journals Online (AJOL)

    In this paper, Bonilla-Silva's structural theory of racism is used as a theo- retical lens to unpack the rationalisations used by four white pre-service teachers to make sense of race and their own racial identities. By claiming that they were not part of apartheid, the participants use various rationalisations to provide them with ...

  7. Volterra integral equation-factorisation method and nucleus ...

    Indian Academy of Sciences (India)

    U LAHA

    2018-02-28

    Feb 28, 2018 ... supersymmetry-inspired factorisation method, this solution is exploited to construct higher partial wave interactions. The merit of our approach is ... Although all elementary and advanced parts of theo- retical physics are ... deuteron binding energy and S-wave scattering lengths. We shall try to generate α−α ...

  8. Boekbesprekings

    African Journals Online (AJOL)

    of individual authors along the way and offers insightful critiques of each. He does so in such a way as to make sense of a complex chronicle of theo ries and counter theories. His clarifi cation of the methodology used in addressing the problem of the rela tionship of the Synoptic Gospels and the Gospel of John sheds light ...

  9. Riemann Integration

    Indian Academy of Sciences (India)

    Riemann had revolutionized the fields of analy- sis, geometry and mathematical physics. His ideas concerning geometry of space had a pro- found effect on the development of modern theo- retical physics. Riemannian manifolds, Riemann surfaces, the Cauchy-Riemann equations, the Rie- mann hypothesis - all these and ...

  10. Pop / Mart Kalvet

    Index Scriptorium Estoniae

    Kalvet, Mart, 1975-

    2007-01-01

    Uutest heliplaatidest: The Mission "God Is A Bullet", James Yorkston "Roaring The Gospel", Groove Armada "Soundboy Rock", Elektrons "Red Light Don't Stop", Mutya Buena "Real Girl", Rounce "17 aastat", Karizma "A Mind Of It's Own", Theo Parrish "Sound Sculptures vol. 1", Plaan B "Puupeatus"

  11. Design of nanocomposite film-based plasmonic device for gas sensing

    Indian Academy of Sciences (India)

    Abstract. Surface plasmon resonance (SPR) is a very efficient tool for chemical and biological sensing in nanotechnology, nanobiotechnology, medicine and environmental monitoring. A theo- retical simulation study incorporating the use of admittance loci design methodology in SPR-based sensing device using ...

  12. Use of dika fat in the formulation of sustained release theophylline ...

    African Journals Online (AJOL)

    The USP XX paddle method was used. A level of sustained release was achieved over a 6-h period in both the tabletted and encapsulated dosage forms. The theophylline formulations containing dika fat, prepared in this study, exhibited dissolution profiles similar to those of Theo 24, Theodur and Respid, some commercial ...

  13. 78 FR 19172 - Endangered and Threatened Wildlife and Plants; Endangered Status for the Diamond Darter and...

    Science.gov (United States)

    2013-03-29

    ... complete and accurate. (10) The likelihood of adverse social reactions to the designation of critical... importance of habitat protection, and, where a Federal nexus exists, increased habitat protection for the....O. 13132 (Federalism), E.O. 12988 (Civil Justice Reform), E.O. 13211 (Energy, Supply, Distribution...

  14. Need for Re-introduction of Reading Corners in Primary School ...

    African Journals Online (AJOL)

    The paper looks at the practical and theo retical considerations for stakeholders for re-introduction of reading comers in primary school libraries in Nigeria. It laid emphasis on the use of non-conventional school libraries to introduce primary school, pupils to library services. JIt identifies the. problems facing school libraries, ...

  15. Lessons from Innovations

    NARCIS (Netherlands)

    van der Voordt, Theo; van Meel, JJ; Dewulf, G.; Krumm, P.; de Jonge, H.

    2000-01-01

    Juriaan van Meel and Theo van der Voordt describe the interaction between workplace concepts and the functioning of organisations and individual employees. Although scientific evaluations are scarce, it may be concluded that innovative concepts fit better with new ways of working. Teleworking and

  16. 'Why is there no NATO in Asia?'

    DEFF Research Database (Denmark)

    He, Kai; Feng, Huiyun

    2012-01-01

    Why did the US prefer multilateral alliances in Europe, but bilateral alliances in Asia after World War II? Rationalists and constructivists debate the impact of power, institutions, and identities in explaining this highly contested question. We introduce a new argument embedded in prospect theo...

  17. Between the real and the ideal. Ministerial formation in South African ...

    African Journals Online (AJOL)

    In the last chapter, the way forward for ministerial formation is sketched. The South African context of theological education includes the changing landscape of higher education, as well as the changing models of theo- logical education, among other reasons for this being the growth of the church in Africa. The recurring ...

  18. From Braitenberg's Vehicles to Jansen's Beach Animals: Towards an Ecological Approach to the Design of Non-Organic Intelligence

    NARCIS (Netherlands)

    Bleeker, M.A.

    2017-01-01

    This article presents a comparison of two proposals for how to conceive of the evolution of non-organic intelligence. One is Valentino Braitenberg’s 1984 essay ‘Vehicles: Experiments in Synthetic Psychology’. The other is the Strandbeesten (beach animals) of Dutch engineer-artist Theo Jansen.

  19. QPFT operator algebras and commutative exterior differential calculus

    International Nuclear Information System (INIS)

    Yur'ev, D.V.

    1993-01-01

    The reduction of the structure theory of the operator algebras of quantum projective (sl(2, C)-invariant) field theory (QPFT operator algebras) to a commutative exterior differential calculus by means of the operation of renormalization of a pointwise product of operator fields is described. In the first section, the author introduces the concept of the operator algebra of quantum field theory and describes the operation of the renormalization of a pointwise product of operator fields. The second section is devoted to a brief exposition of the fundamentals of the structure theory of QPT operator algebras. The third section is devoted to commutative exterior differential calculus. In the fourth section, the author establishes the connection between the renormalized pointwise product of operator fields in QPFT operator algebras and the commutative exterior differential calculus. 5 refs

  20. New accurate theoretical line lists of 12CH4 and 13CH4 in the 0-13400 cm-1 range: Application to the modeling of methane absorption in Titan's atmosphere

    Science.gov (United States)

    Rey, Michaël; Nikitin, Andrei V.; Bézard, Bruno; Rannou, Pascal; Coustenis, Athena; Tyuterev, Vladimir G.

    2018-03-01

    The spectrum of methane is very important for the analysis and modeling of Titan's atmosphere but its insufficient knowledge in the near infrared, with the absence of reliable absorption coefficients, is an important limitation. In order to help the astronomer community for analyzing high-quality spectra, we report in the present work the first accurate theoretical methane line lists (T = 50-350 K) of 12CH4 and 13CH4 up to 13400 cm-1 ( > 0.75 μm). These lists are built from extensive variational calculations using our recent ab initio potential and dipole moment surfaces and will be freely accessible via the TheoReTS information system (http://theorets.univ-reims.fr, http://theorets.tsu.ru). Validation of these lists is presented throughout the present paper. For the sample of lines where upper energies were available from published analyses of experimental laboratory 12CH4 spectra, small empirical corrections in positions were introduced that could be useful for future high-resolution applications. We finally apply the TheoRetS line list to model Titan spectra as observed by VIMS and by DISR, respectively onboard Cassini and Huygens. These data are used to check that the TheoReTS line lists are able to model observations. We also make comparisons with other experimental or theoretical line lists. It appears that TheoRetS gives very reliable results better than ExoMol and even than HITRAN2012, except around 1.6 μm where it gives very similar results. We conclude that TheoReTS is suitable to be used for the modeling of planetary radiative transfer and photometry. A re-analysis of spectra recorded by the DISR instrument during the descent of the Huygens probe suggests that the CH4 mixing ratio decreases with altitude in Titan's stratosphere, reaching a value of ∼10-2 above the 110 km altitude.

  1. Fractal stock markets: International evidence of dynamical (in)efficiency.

    Science.gov (United States)

    Bianchi, Sergio; Frezza, Massimiliano

    2017-07-01

    The last systemic financial crisis has reawakened the debate on the efficient nature of financial markets, traditionally described as semimartingales. The standard approaches to endow the general notion of efficiency of an empirical content turned out to be somewhat inconclusive and misleading. We propose a topological-based approach to quantify the informational efficiency of a financial time series. The idea is to measure the efficiency by means of the pointwise regularity of a (stochastic) function, given that the signature of a martingale is that its pointwise regularity equals 12. We provide estimates for real financial time series and investigate their (in)efficient behavior by comparing three main stock indexes.

  2. Homogeneous approximation property for continuous shearlet transforms in higher dimensions

    Directory of Open Access Journals (Sweden)

    Yu Su

    2016-07-01

    Full Text Available Abstract This paper is concerned with the generalization of the homogeneous approximation property (HAP for a continuous shearlet transform to higher dimensions. First, we give a pointwise convergence result on the inverse shearlet transform in higher dimensions. Second, we show that every pair of admissible shearlets possess the HAP in the sense of L 2 ( R d $L^{2}(R^{d}$ . Third, we give a sufficient condition for the pointwise HAP to hold, which depends on both shearlets and functions to be reconstructed.

  3. Fractal stock markets: International evidence of dynamical (in)efficiency

    Science.gov (United States)

    Bianchi, Sergio; Frezza, Massimiliano

    2017-07-01

    The last systemic financial crisis has reawakened the debate on the efficient nature of financial markets, traditionally described as semimartingales. The standard approaches to endow the general notion of efficiency of an empirical content turned out to be somewhat inconclusive and misleading. We propose a topological-based approach to quantify the informational efficiency of a financial time series. The idea is to measure the efficiency by means of the pointwise regularity of a (stochastic) function, given that the signature of a martingale is that its pointwise regularity equals 1/2 . We provide estimates for real financial time series and investigate their (in)efficient behavior by comparing three main stock indexes.

  4. Distributed mean curvature on a discrete manifold for Regge calculus

    International Nuclear Information System (INIS)

    Conboye, Rory; Miller, Warner A; Ray, Shannon

    2015-01-01

    The integrated mean curvature of a simplicial manifold is well understood in both Regge Calculus and Discrete Differential Geometry. However, a well motivated pointwise definition of curvature requires a careful choice of the volume over which to uniformly distribute the local integrated curvature. We show that hybrid cells formed using both the simplicial lattice and its circumcentric dual emerge as a remarkably natural structure for the distribution of this local integrated curvature. These hybrid cells form a complete tessellation of the simplicial manifold, contain a geometric orthonormal basis, and are also shown to give a pointwise mean curvature with a natural interpretation as the fractional rate of change of the normal vector. (paper)

  5. SUBGR: A Program to Generate Subgroup Data for the Subgroup Resonance Self-Shielding Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kang Seog [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-06-06

    The Subgroup Data Generation (SUBGR) program generates subgroup data, including levels and weights from the resonance self-shielded cross section table as a function of background cross section. Depending on the nuclide and the energy range, these subgroup data can be generated by (a) narrow resonance approximation, (b) pointwise flux calculations for homogeneous media; and (c) pointwise flux calculations for heterogeneous lattice cells. The latter two options are performed by the AMPX module IRFFACTOR. These subgroup data are to be used in the Consortium for Advanced Simulation of Light Water Reactors (CASL) neutronic simulator MPACT, for which the primary resonance self-shielding method is the subgroup method.

  6. Dielectric and electromechanical properties of LiNbO3-modified (BiNa)TiO3-(BaCa)TiO3 lead-free piezoceramics

    Science.gov (United States)

    Zaman, Arif; Hussain, Ali; Malik, Rizwan Ahmed; Maqbool, Adnan; Nahm, Sahn; Kim, Myong-Ho

    2016-05-01

    The dielectric and electromechanical properties of LiNbO3-modified (1-x) [0.91Na0.5Bi0.5TiO3-0.09Ba0.70Ca0.30TiO3]-xLiNbO3 (abbreviated as (BiNa)TiO3-(BaCa)TiO3-LN) lead-free piezoceramics were investigated. The electrical properties revealed that the addition of LiNbO3 (LN) induces a phase transition from a non-ergodic relaxor to an ergodic relaxor in the (BiNa)TiO3-(BaCa)TiO3-LN system. A large electrostrain of ~0.418% with a normalized strain of ~690 pm V-1 at 6 kV mm-1 was observed at the coexistence of the non-ergodic relaxor and ergodic relaxor phases for LN 0.020, where a field-assisted reversible phase transition between metastable ferroelectric and stable ergodic relaxor phases occurs. Subsequently, a gradual enhancement in the temperature stability of the dielectric constant was observed. At 3 mol.% LN, a nearly constant temperature and a frequency-invariant permittivity of ɛ r ~ 3300 over a broad temperature range of 147 °C-306 °C was observed along with small losses from room temperature up to 400 °C.

  7. A Basic Inequality for Submanifolds in Locally Conformal almost ...

    Indian Academy of Sciences (India)

    For submanifolds tangent to the structure vector field in locally conformal almost cosymplectic manifolds of pointwise constant -sectional curvature, we establish a basic inequality between the main intrinsic invariants of the submanifold on one side, namely its sectional curvature and its scalar curvature; and its main ...

  8. Improved endpoint bounds for the lacunary spherical maximal operator

    OpenAIRE

    Cladek, Laura; Krause, Ben

    2017-01-01

    We prove new endpoint bounds for the lacunary spherical maximal operator and as a consequence obtain almost everywhere pointwise convergence of lacunary spherical means for functions locally in $L\\log\\log\\log L(\\log\\log\\log\\log L)^{1+\\epsilon}$ for any $\\epsilon>0$.

  9. Moderate deviations principles for the kernel estimator of ...

    African Journals Online (AJOL)

    Abstract. The aim of this paper is to provide pointwise and uniform moderate deviations principles for the kernel estimator of a nonrandom regression function. Moreover, we give an application of these moderate deviations principles to the construction of condence regions for the regression function. Resume. L'objectif de ...

  10. LES based POD analysis of Jet in Cross Flow

    DEFF Research Database (Denmark)

    Cavar, Dalibor; Meyer, Knud Erik; Jakirlic, S.

    2010-01-01

    The paper presents results of a POD investigation of the LES based numerical simulation of the jet-in-crossflow (JICF) flowfield. LES results are firstly compared to the pointwise LDA measurements. 2D POD analysis is then used as a comparison basis for PIV measurements and LES, and finally 3D POD...

  11. rights reserved Generalization and Modification of Hardy-Littlewood ...

    African Journals Online (AJOL)

    ADOWIE PERE

    2018-03-20

    Mar 20, 2018 ... Keywords: Maximal function, Hardy-Littlewood Maximal Functions, Borel measure, Fourier coefficient. Maximal functions arise very natural in analysis, for proving theorems about the existence almost everywhere of limits, for controlling pointwise important objects such as the Poisson Integrals or for.

  12. Relaxation schemes for Chebyshev spectral multigrid methods

    Science.gov (United States)

    Kang, Yimin; Fulton, Scott R.

    1993-01-01

    Two relaxation schemes for Chebyshev spectral multigrid methods are presented for elliptic equations with Dirichlet boundary conditions. The first scheme is a pointwise-preconditioned Richardson relaxation scheme and the second is a line relaxation scheme. The line relaxation scheme provides an efficient and relatively simple approach for solving two-dimensional spectral equations. Numerical examples and comparisons with other methods are given.

  13. Fusion de données RVB-D par stéréophotométrie colorée

    DEFF Research Database (Denmark)

    Quéau, Yvain; Durix, Bastien; Lucas, Tom

    We propose a new approach of photometric stereo with ani- sotropic pointwise sources such as LEDs. This approach is both differential and variational, in order to recover the depth directly and in a robust manner, without estimating the normals and the albedo in a first step. We then show how to ...

  14. Transportation and concentration inequalities for bifurcating Markov chains

    DEFF Research Database (Denmark)

    Penda, S. Valère Bitseki; Escobar-Bach, Mikael; Guillin, Arnaud

    2017-01-01

    concentration inequalities.We also study deviation inequalities for the empirical means under relaxed assumptions on the Wasserstein contraction for the Markov kernels. Applications to bifurcating nonlinear autoregressive processes are considered for point-wise estimates of the non-linear autoregressive...

  15. Turbulent flux and the diffusion of passive tracers in electrostatic turbulence

    DEFF Research Database (Denmark)

    Basu, R.; Jessen, T.; Naulin, V.

    2003-01-01

    The connection between the diffusion of passive tracer particles and the anomalous turbulent flux in electrostatic drift-wave turbulence is investigated by direct numerical solutions of the 2D Hasegawa-Wakatani equations. The probability density functions for the point-wise and flux surface...

  16. Operations Between Functions

    DEFF Research Database (Denmark)

    Gardner, Richard J.; Kiderlen, Markus

    A structural theory of operations between real-valued (or extended-real-valued) functions on a nonempty subset A of Rn is initiated. It is shown, for example, that any operation ∗ on a cone of functions containing the constant functions, which is pointwise, positively homogeneous, monotonic...

  17. Restricted uniform boundedness in Banach spaces | Nygaard ...

    African Journals Online (AJOL)

    Precise conditions for a subset A of a Banach space X are known in order that pointwise bounded on A sequences of bounded linear functionals on X are uniformly bounded. In this paper, we study such conditions under the extra assumption that the functionals belong to a given linear subspace Γ of X*. When Γ = X*, these ...

  18. Oscillation estimates relative to p-homogeneous forms and Kato measures data

    Directory of Open Access Journals (Sweden)

    Marco Biroli

    2006-11-01

    Full Text Available We state pointwise estimate for the positive subsolutions associated to a p-homogeneous form and nonnegative Radon measures data. As a by-product we establish an oscillation’s estimate for the solutions relative to Kato measures data.

  19. On the solution of the Liouville equation over a rectangle

    Directory of Open Access Journals (Sweden)

    A. M. Arthurs

    1996-01-01

    Full Text Available Methods for integral equations are used to derive pointwise bounds for the solution of a boundary value problem for the nonlinear Liouville partial differential equation over a rectangle. Several test calculations are performed and the resulting solutions are more accurate than those obtained previously by other methods.

  20. A Note on the Asymptotic Normality of the Kernel Deconvolution Density Estimator with Logarithmic Chi-Square Noise

    Directory of Open Access Journals (Sweden)

    Yang Zu

    2015-07-01

    Full Text Available This paper studies the asymptotic normality for the kernel deconvolution estimator when the noise distribution is logarithmic chi-square; both identical and independently distributed observations and strong mixing observations are considered. The dependent case of the result is applied to obtain the pointwise asymptotic distribution of the deconvolution volatility density estimator in discrete-time stochastic volatility models.

  1. The Ellis semigroup of a nonautonomous discrete dynamical system ...

    African Journals Online (AJOL)

    We introduce the Ellis semigroup of a nonautonomous discrete dynamical system (X, f1,∞) when X is a metric compact space. The underlying set of this semigroup is the pointwise closure of {fn1| n ∈ N) in the space Xx. By using the convergence of a sequence of points with respect to an ultrafilter it is possible to give a ...

  2. Preparation and investigation of optical, structural, and ...

    Indian Academy of Sciences (India)

    determined using point-wise unconstrained minimization approach (PUMA) and fitting the data to the Cauchy formula for thin films [25]. Infrared spectrum of the samples was measured by using Fourier transform infrared (FTIR) spectrophotometer (Bruker model. Vertex 70) for identifying the molecular composition.

  3. The Random Material Point Method

    NARCIS (Netherlands)

    Wang, B.; Vardon, P.J.; Hicks, M.A.

    2017-01-01

    The material point method is a finite element variant which allows the material, represented by a point-wise discretization, to move through the background mesh. This means that large deformations, such as those observed post slope failure, can be computed. By coupling this material level

  4. A Banach algebra of functions of several variables of finite total variation and Lipschitzian superposition operators. I

    NARCIS (Netherlands)

    Chistyakov, VV

    2005-01-01

    It is shown that the space of functions of n real variables with finite total variation in the sense of Vitali, Hardy and Krause, defined on a rectangle I-a(b) C R-n, is a Banach algebra under the pointwise operations and Hildebrandt-Leonov's norm. This result generalizes the classical case of

  5. Theory of Sobolev multipliers

    CERN Document Server

    Shaposhnikova, Tatyana O

    2008-01-01

    Offers a comprehensive exposition of the theory of pointwise multipliers acting in pairs of spaces of differentiable functions. This book covers topics such as: trace inequalities, analytic characterization of multipliers, relations between spaces of Sobolev multipliers and other function spaces, and maximal subalgebras of multiplier spaces.

  6. Non-Parametric Analysis of Rating Transition and Default Data

    DEFF Research Database (Denmark)

    Fledelius, Peter; Lando, David; Perch Nielsen, Jens

    2004-01-01

    We demonstrate the use of non-parametric intensity estimation - including construction of pointwise confidence sets - for analyzing rating transition data. We find that transition intensities away from the class studied here for illustration strongly depend on the direction of the previous move b...

  7. Classification of the spaces Cp*(X) within the Borel-Wadge hierarchy for a projective space X

    Czech Academy of Sciences Publication Activity Database

    Doležal, Martin; Vejnar, B.

    2015-01-01

    Roč. 183, March (2015), s. 11-17 ISSN 0166-8641 Institutional support: RVO:67985840 Keywords : function spaces * pointwise convergence * projective determinacy Subject RIV: BA - General Mathematics Impact factor: 0.493, year: 2015 http://www.sciencedirect.com/science/article/pii/S0166864114004854

  8. Nonparametric confidence intervals for monotone functions

    NARCIS (Netherlands)

    Groeneboom, P.; Jongbloed, G.

    2015-01-01

    We study nonparametric isotonic confidence intervals for monotone functions. In [Ann. Statist. 29 (2001) 1699–1731], pointwise confidence intervals, based on likelihood ratio tests using the restricted and unrestricted MLE in the current status model, are introduced. We extend the method to the

  9. Nonparametric Estimation of Cumulative Incidence Functions for Competing Risks Data with Missing Cause of Failure

    DEFF Research Database (Denmark)

    Effraimidis, Georgios; Dahl, Christian Møller

    In this paper, we develop a fully nonparametric approach for the estimation of the cumulative incidence function with Missing At Random right-censored competing risks data. We obtain results on the pointwise asymptotic normality as well as the uniform convergence rate of the proposed nonparametri...

  10. The Effect of the Use of Number Lines Representations on Student Understanding of Basic Function Concepts.

    Science.gov (United States)

    Olsen, James R.

    Researchers and educators are calling for increased use of technology and attention to function concepts in school mathematics. Students often have considerable difficulty gleaning pointwise and global information from Cartesian (R squared) representations of functions, whether they are hand- or machine-produced. Described here is an interactive…

  11. Uniqueness for inverse problems of determining orders of multi-term time-fractional derivatives of diffusion equation

    OpenAIRE

    Li, Zhiyuan; Yamamoto, Masahiro

    2014-01-01

    This article proves the uniqueness for two kinds of inverse problems of identifying fractional orders in diffusion equations with multiple time-fractional derivatives by pointwise observation. By means of eigenfunction expansion and Laplace transform, we reduce the uniqueness for our inverse problems to the uniqueness of expansions of some special function and complete the proof.

  12. Visual Field Outcomes for the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT)

    Science.gov (United States)

    Wall, Michael; Johnson, Chris A.; Cello, Kimberly E.; Zamba, K. D.; McDermott, Michael P.; Keltner, John L.

    2016-01-01

    Purpose The Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) showed that acetazolamide provided a modest, significant improvement in mean deviation (MD). Here, we further analyze visual field changes over the 6-month study period. Methods Of 165 subjects with mild visual loss in the IIHTT, 125 had perimetry at baseline and 6 months. We evaluated pointwise linear regression of visual sensitivity versus time to classify test locations in the worst MD (study) eye as improving or not; pointwise changes from baseline to month 6 in decibels; and clinical consensus of change from baseline to 6 months. Results The average study eye had 36 of 52 test locations with improving sensitivity over 6 months using pointwise linear regression, but differences between the acetazolamide and placebo groups were not significant. Pointwise results mostly improved in both treatment groups with the magnitude of the mean change within groups greatest and statistically significant around the blind spot and the nasal area, especially in the acetazolamide group. The consensus classification of visual field change from baseline to 6 months in the study eye yielded percentages (acetazolamide, placebo) of 7.2% and 17.5% worse, 35.1% and 31.7% with no change, and 56.1% and 50.8% improved; group differences were not statistically significant. Conclusions In the IIHTT, compared to the placebo group, the acetazolamide group had a significant pointwise improvement in visual field function, particularly in the nasal and pericecal areas; the latter is likely due to reduction in blind spot size related to improvement in papilledema. (ClinicalTrials.gov number, NCT01003639.) PMID:26934136

  13. Correlation decay in certain soft billiards

    CERN Document Server

    Balint, P

    2003-01-01

    Motivated by the 2D finite horizon periodic Lorentz gas, soft planar billiard systems with axis-symmetric potentials are studied in this paper. Since Sinai's celebrated discovery that elastic collisions of a point particle with strictly convex scatterers give rise to hyperbolic, and consequently, nice ergodic behaviour, several authors (most notably Sinai, Kubo, Knauf) have found potentials with analogous properties. These investigations concluded in the work of V. Donnay and C. Liverani who obtained general conditions for a 2-D rotationally symmetric potential to provide ergodic dynamics. Our main aim here is to understand when these potentials lead to stronger stochastic properties, in particular to exponential decay of correlations and central limit theorem. In the main argument we work with systems in general for which the rotation function satisfies certain conditions. One of these conditions has already been used by Donnay and Liverani to obtain hyperbolicity and ergodicity. What we prove is that if, in...

  14. Conjugacy, orbit equivalence and classification of measure-preserving group actions

    DEFF Research Database (Denmark)

    Törnquist, Asger Dag

    2009-01-01

    . Further, we obtain that the measure-preserving almost-everywhere-free ergodic actions of such a G cannot be classified up to orbit equivalence by a reasonable assignment of countable structures as complete invariants. We also obtain a strengthening and a new proof of a non-classification result of Foreman......We prove that if G is a countable discrete group with property (T) over an infinite subgroup HG which contains an infinite Abelian subgroup or is normal, then G has continuum-many orbit-inequivalent measure-preserving almost-everywhere-free ergodic actions on a standard Borel probability space...... and Weiss for conjugacy of measure-preserving ergodic almost-everywhere-free actions of discrete countable groups....

  15. Superposition Enhanced Nested Sampling

    Directory of Open Access Journals (Sweden)

    Stefano Martiniani

    2014-08-01

    Full Text Available The theoretical analysis of many problems in physics, astronomy, and applied mathematics requires an efficient numerical exploration of multimodal parameter spaces that exhibit broken ergodicity. Monte Carlo methods are widely used to deal with these classes of problems, but such simulations suffer from a ubiquitous sampling problem: The probability of sampling a particular state is proportional to its entropic weight. Devising an algorithm capable of sampling efficiently the full phase space is a long-standing problem. Here, we report a new hybrid method for the exploration of multimodal parameter spaces exhibiting broken ergodicity. Superposition enhanced nested sampling combines the strengths of global optimization with the unbiased or athermal sampling of nested sampling, greatly enhancing its efficiency with no additional parameters. We report extensive tests of this new approach for atomic clusters that are known to have energy landscapes for which conventional sampling schemes suffer from broken ergodicity. We also introduce a novel parallelization algorithm for nested sampling.

  16. Spherical grand-canonical minority games with and without score discounting

    International Nuclear Information System (INIS)

    Bladon, Alex; Richardson, Thomas; Galla, Tobias

    2009-01-01

    We present a spherical version of the grand-canonical minority game (GCMG) and solve its dynamics in the stationary state. The model displays several types of transitions between multiple ergodic phases and one non-ergodic phase. We derive analytical solutions, including exact expressions for the volatility, throughout all ergodic phases and compute the phase behaviour of the system. In contrast to conventional GCMGs, where the introduction of memory loss precludes analytical approaches, the spherical model can also be solved when exponential discounting is taken into account. For the case of homogeneous incentives to trade ε and memory-loss rates ρ, an efficient phase is found only if ρ = ε = 0. Allowing for heterogeneous memory-loss rates we find that efficiency can be achieved as long as there is any finite fraction of agents which is not subject to memory loss

  17. Measurement of event shape distributions and moments in $e^{+}e^{-} \\to$ hadrons at 91-209 GeV and a determination of $\\alpha_{s}$

    CERN Document Server

    Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Amaral, P.; Anagnostou, G.; Anderson, K.J.; Asai, S.; Axen, D.; Bailey, I.; Barberio, E.; Barillari, T.; Barlow, R.J.; Batley, R.J.; Bechtle, P.; Behnke, T.; Bell, Kenneth Watson; Bell, P.J.; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Boeriu, O.; Bock, P.; Boutemeur, M.; Braibant, S.; Brown, Robert M.; Burckhart, H.J.; Campana, S.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, D.G.; Ciocca, C.; Csilling, A.; Cuffiani, M.; Dado, S.; Roeck, A.De; Wolf, E.A.De; Desch, K.; Dienes, B.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Etzion, E.; Fabbri, F.; Fanfani, A.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Gagnon, P.; Gary, John William; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Giunta, Marina; Goldberg, J.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G.G.; Harel, A.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hill, J.C.; Hoffman, Kara Dion; Horvath, D.; Igo-Kemenes, P.; Ishii, K.; Jeremie, H.; Jovanovic, P.; Junk, T.R.; Kanzaki, J.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kluth, S.; Kobayashi, T.; Kobel, M.; Komamiya, S.; Kramer, T.; Krieger, P.; Krogh, J.von; Kuhl, T.; Kupper, M.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lellouch, D.; Lettso, J.; Levinson, L.; Lillich, J.; Lloyd, S.L.; Loebinger, F.K.; Lu, J.; Ludwig, A.; Ludwig, J.; Mader, W.; Marcellini, S.; Martin, A.J.; Masetti, G.; Mashimo, T.; Mattig, Peter; McKenna, J.; McPherson, R.A.; Meijers, F.; Menges, W.; Merritt, F.S.; Mes, H.; Meyer, Niels T.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Montanari, A.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Nanjo, H.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oh, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Pooth, O.; Przybycien, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Roney, J.M.; Rozen, Y.; Runge, K.; Sachs, K.; Saeki, T.; Sarkisyan, E.K.G.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schorner-Sadenius, T.; Schroder, Matthias; Schumacher, M.; Seuster, R.; Shears, T.G.; Shen, B.C.; Sherwood, P.; Skuja, A.; Smith, A.M.; Sobie, R.; Soldner-Rembold, S.; Spano, F.; Stahl, A.; Strom, David M.; Strohmer, R.; Tarem, S.; Tasevsky, M.; Teuscher, R.; Thomson, M.A.; Torrence, E.; Toya, D.; Tran, P.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Ujvari, B.; Vollmer, C.F.; Vannerem, P.; Vertesi, R.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wilson, G.W.; Wilson, J.A.; Wolf, G.; Wyatt, T.R.; Yamashita, S.; Zer-Zion, D.; Zivkovic, Lidija; CERN. Geneva

    2005-01-01

    We have studied hadronic events from e+e- annihilation data at centre-of-mass energies from 91 to 209 GeV. We present distributions of event shape observables and their moments at each energy and compare with QCD Monte Carlo models. From the event shape distributions we extract the strong coupling alpha_s and test its evolution with energy scale. The results are consistent with the running of alpha_s expected from QCD. Combining all data, the value of alpha_s (M_z) is determined to be alpha_s(Mz)=0.1191+-0.0005(stat.)+-0.0010 (expt.)+-0.0011(hadr.)+-0.0044(theo.) The energy evolution of the moments is also used to determine a value of alpha_ with slightly larger errors: alpha_s(Mz)=0.1223+-0.0005(stat.) +-0.0014(expt.) +-0.0016(hadr.) +0.0054 -0.0036 (theo).

  18. Descolonização

    Directory of Open Access Journals (Sweden)

    Vera Lucia Amaral Ferlini

    1977-12-01

    Full Text Available SANTHIAGO, Theo (Org.. Descolonização. Trad. Antônio Monteiro Guimarães Filho, Theo Santhiago e José Fernandes Dias. Rio de Janeiro: Francisco Alves, 1977, 200 pp. (primeiro parágrafo da resenha A nova conjuntura de luta anti-colonial, marcada pelo término da Guerra do Vietnã, pela emancipação das colônias portuguesas, pela polêmica de Uganda, pelos eventos atuais da Rodésia e da África do Sul, estimulou a retomada do estudo dos movimentos nacionais. A superação do colonialismo externo, por sua vez, desnudou um novo tipo de colonialismo — contra as minorias étnicas e nacionais, que lutam pela sua sobrevivência que tem sido objeto da reflexão dos especialistas.

  19. Measurement of the W Boson Mass with the D0 Run II Detector using the Electron P(T) Spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Andeen, Jr., Timothy R. [Northwestern Univ., Evanston, IL (United States)

    2008-06-01

    This thesis is a description of the measurement of the W boson mass using the D0 Run II detector with 770 pb-1 of p$\\bar{p}$ collision data. These collisions were produced by the Tevatron at √s = 1.96 TeV between 2002 and 2006. We use a sample of W → ev and Z → ee decays to determine the W boson mass with the transverse momentum distribution of the electron and the transverse mass distribution of the boson. We measure MW = 80340 ± 37 (stat.) ± 26 (sys. theo.) ± 51 (sys. exp.) MeV = 80340 ± 68 MeV with the transverse momentum distribution of the electron and MW = 80361 ± 28 (stat.) ± 17 (sys. theo.) ± 51 (sys. exp.) MeV = 80361 ± 61 MeV with the transverse mass distribution.

  20. Determination of the strong coupling constant $\\alpha_s$ in multijet production with the ATLAS detector at the LHC.

    CERN Document Server

    Llorente Merino, Javier; The ATLAS collaboration

    2018-01-01

    A measurement of transverse energy--energy correlations and its asymmetry in $pp$ collisions recorded by the ATLAS detector at the LHC at $\\sqrt{s} = 8$ TeV is presented. The results are intepreted as a precision test of Quantum Chromodynamics, used to determine the strong coupling constant $\\alpha_s(m_Z)$ and to test asymptotic freedom up to scales close to 1 TeV. A global fit to the transverse energy--energy correlation distributions yields $\\alpha_{\\mathrm{s}}(m_Z) = 0.1162 \\pm 0.0011 \\mbox{ (exp.)}^{+0.0084}_{-0.0070} \\mbox{ (theo.)}$, while a global fit to the asymmetry distributions yields a value of $\\alpha_{\\mathrm{s}}(m_Z) = 0.1196 \\pm 0.0013 \\mbox{ (exp.)}^{+0.0075}_{-0.0045} \\mbox{ (theo.)}$.

  1. Quantum Entropy and Complexity

    Science.gov (United States)

    Benatti, F.; Oskouei, S. Khabbazi; Abad, A. Shafiei Deh

    We study the relations between the recently proposed machine-independent quantum complexity of P. Gacs [1] and the entropy of classical and quantum systems. On one hand, by restricting Gacs complexity to ergodic classical dynamical systems, we retrieve the equality between the Kolmogorov complexity rate and the Shannon entropy rate derived by A. A. Brudno [2]. On the other hand, using the quantum Shannon-McMillan theorem [3], we show that such an equality holds densely in the case of ergodic quantum spin chains.

  2. Sinai-Ruelle-Bowen measure for normal form map of grazing bifurcations of impact oscillators

    Science.gov (United States)

    Li, Denghui; Chen, Hebai; Xie, Jianhua; Zhang, Jiye

    2017-09-01

    Grazing bifurcations are typical non-smooth bifurcations that occur in impact oscillators. They are described by a discrete map with square-root singularities. In this paper we study the structure of a strange attractor which is the closure of the unstable manifold at hyperbolic fixed point of the normal form map for grazing bifurcations of one-degree-of-freedom impact oscillators from the ergodic theoretic point of view. We prove that for some set of values of the parameters this map has an Sinai-Ruelle-Bowen measure which is supported on the strange attractor and is ergodic.

  3. Markov chain analysis of single spin flip Ising simulations

    International Nuclear Information System (INIS)

    Hennecke, M.

    1997-01-01

    The Markov processes defined by random and loop-based schemes for single spin flip attempts in Monte Carlo simulations of the 2D Ising model are investigated, by explicitly constructing their transition matrices. Their analysis reveals that loops over all lattice sites using a Metropolis-type single spin flip probability often do not define ergodic Markov chains, and have distorted dynamical properties even if they are ergodic. The transition matrices also enable a comparison of the dynamics of random versus loop spin selection and Glauber versus Metropolis probabilities

  4. Poisson Autoregression

    DEFF Research Database (Denmark)

    Fokianos, Konstantinos; Rahbæk, Anders; Tjøstheim, Dag

    This paper considers geometric ergodicity and likelihood based inference for linear and nonlinear Poisson autoregressions. In the linear case the conditional mean is linked linearly to its past values as well as the observed values of the Poisson process. This also applies to the conditional...... proceeds via Markov theory and irreducibility. Finding transparent conditions for proving ergodicity turns out to be a delicate problem in the original model formulation. This problem is circumvented by allowing a perturbation of the model. We show that as the perturbations can be chosen to be arbitrarily...

  5. Low SNR Capacity of FSO Links over Gamma-Gamma Atmospheric Turbulence Channels

    KAUST Repository

    Benkhelifa, Fatma

    2013-02-23

    In this paper, we study the ergodic capacity of free space optical communication systems over Gamma-Gamma atmospheric turbulence fading channels with perfect channel state information at both the transmitter and the receiver. In our framework, we mainly focus on the low signal-to-noise ratio range and show that the ergodic capacity scales proportionally to SNR log^4(1/SNR). We show also that one-bit CSI feedback at the transmitter is enough to achieve this capacity using an on-off power control scheme.

  6. Low SNR Capacity of FSO Links over Gamma-Gamma Atmospheric Turbulence Channels

    KAUST Repository

    Benkhelifa, Fatma

    2013-01-27

    In this paper, we study the ergodic capacity of free space optical communication systems over Gamma-Gamma atmospheric turbulence fading channels with perfect channel state information at both the transmitter and the receiver. In our framework, we mainly focus on the low signal-to-noise ratio range and show that the ergodic capacity scales proportionally to SNR log^4(1/SNR). We show also that one-bit CSI feedback at the transmitter is enough to achieve this capacity using an on-o ff power control scheme.

  7. Lyapunov exponents

    CERN Document Server

    Barreira, Luís

    2017-01-01

    This book offers a self-contained introduction to the theory of Lyapunov exponents and its applications, mainly in connection with hyperbolicity, ergodic theory and multifractal analysis. It discusses the foundations and some of the main results and main techniques in the area, while also highlighting selected topics of current research interest. With the exception of a few basic results from ergodic theory and the thermodynamic formalism, all the results presented include detailed proofs. The book is intended for all researchers and graduate students specializing in dynamical systems who are looking for a comprehensive overview of the foundations of the theory and a sample of its applications.

  8. Interpretation of the T-H phase diagram of HTSC in the frame of superconductive granular layer model

    International Nuclear Information System (INIS)

    Burgij, A.I.; Shadura, V.N.

    1989-01-01

    The model of two-dimensional Coulomb gas on charge substrate is used to describe magnetic properties of high temperature superconductor LaBaCuO. The phase transition from the nonergodic superconducting state to the ergodic one is associated with the melting of Wigner's two-dimensional crystal into the liquid crystal-hexatic, and the phase transition from ergodic superconducting state to the normal one - with the melting of liquid crystal. The T c (H) dependence calculated within these concepts is consistent with that observed in experiment. 22 refs.; 3 figs

  9. Plasma Edge Control in Tore Supra

    International Nuclear Information System (INIS)

    Evans, T.E.; Mioduszewski, P.K.; Foster, C.; Haste, G.; Horton, L.; Grosman, A.; Ghendrih, P.; Chatelier, M.; Capes, H.; Michelis, C. De; Fall, T.; Geraud, A.; Grisolia, C.; Guilhem, D.; Hutter, T.

    1990-01-01

    TORE SUPRA is a large superconducting tokamak designed for sustaining long inductive pulses (t∼ 30 s). In particular, all the first wall components have been designed for steady-state heat and particle exhaust, particle injection, and additional heating. In addition to these technological assets, a strict control of the plasma-wall interactions is required. This has been done at low power: experiments with ohmic heating have been mainly devoted to the pump limiter, ergodic divertor and pellet injection experiments. Some specific problems arising in large tokamaks are encountered; the pump limiter and the ergodic divertor yield the expected effects on the plasma edge. The effects on the bulk are discussed

  10. Response Load Extrapolation for Wind Turbines during Operation Based on Average Conditional Exceedance Rates

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Naess, Arvid; Saha, Nilanjan

    2011-01-01

    within a hierarchical model where the variables that influence the loading are divided into ergodic variables and time-invariant non-ergodic variables. The presented method for statistical response load extrapolation was compared with the existing methods based on peak extrapolation for the blade out...... to cases where the Gumbel distribution is the appropriate asymptotic extreme value distribution. However, two extra parameters are introduced by which a more general and flexible class of extreme value distributions is obtained with the Gumbel distribution as a subclass. The general method is implemented...

  11. The work of Professor Andrzej Lasota on asymptotic stability and recent progress

    Directory of Open Access Journals (Sweden)

    Wojciech Bartoszek

    2008-01-01

    Full Text Available The paper is devoted to Professor Andrzej Lasota's contribution to the ergodic theory of stochastic operators. We have selected some of his important papers and shown their influence on the evolution of this topic. We emphasize the role A. Lasota played in promoting abstract mathematical theories by showing their applications. The article is focused exclusively on ergodic properties of discrete stochastic semigroups \\(\\{P^n : n \\geq 0\\}\\. Nevertheless, almost all of Lasota's results presented here have their one-parameter continuous semigroup analogs.

  12. Pre-coder design over two-symbol extension for K-user cyclic interference channels

    Directory of Open Access Journals (Sweden)

    Hyukjin Chae

    2014-12-01

    Full Text Available The authors consider K-user cyclic single-input–single-output (SISO interference channel (IC where each receiver is interfered with from only one neighbouring transmitter. In the K-user cyclic SISO IC, K/2 sum degrees of freedom can be achieved when two-symbol extension is applied even without channel state information at the transmitter. They derive an approximation of the ergodic sum rate as a function of pre-coders and propose designs of pre-coders to maximise the ergodic sum rate.

  13. The Operation of Autonomous Mobile Robot Assistants in the Environment of Care Facilities Adopting a User-Centered Development Design

    OpenAIRE

    Diego Compagna; Stefan Derpmann; Kathrin Mauz

    2009-01-01

    The participation of the Fraunhofer Institute for Manufacturing Engineering and Automation IPA (Stuttgart, Germany) and the companies User Interface Design GmbH (Ludwigsburg, Germany) plus MLR System GmbH (Ludwigsburg, Germany) enabled the research and findings presented in this paper; we would like to namely mention Birgit Graf and Theo Jacobs (Fraunhofer IPA) furthermore Peter Klein and Christiane Hartmann (User Interface Design GmbH). The successful development of autonomous mobile robo...

  14. Ülemkivi linn ja ehte mõte / Julia Maria Künnap

    Index Scriptorium Estoniae

    Künnap, Julia Maria

    2007-01-01

    2007. a. mais Saksamaal Idar-Obersteinis toimunud ehtekunsti sündmusest "Schmuck-Denken". Trieri ülikooli ehteeriala professori Theo Smeetsi eestvedamisel korraldatud teaduskonverentsist ehteteooria alal. Eestist esines Kadri Mälk. Avati Bernhard Schobingeri näitus villa Bengelis, Eesti Kunstiakadeemia ja Firenze ehtekooli Alchimia ühisnäitus "Twilight" Bengeli tootmisruumides ja Jakob Bengeli fondi stipendiaatide ühisnäitus koolimajas

  15. On the Changes in Lift of Hydrofoils Due to Surface Injections of Polymer Additives

    Science.gov (United States)

    1978-02-01

    no aIn thom ease of 0.l vox ’-trtd ing theo 110e- ativo I’votttro -paks . Also, thet~o eu dCt’tt.!o iva fe e on tlke t’oil’ .n e 00 I’蜳 ý .0k4 01...hydrofoil chord, c.. In -Equation 133 tho .posoitivo -ig applies to tho uipper surface ou, the hydrofoil Wh11i tho.1wk~ ativo pitgn applies to tho lower

  16. Sobre la relación entre la mujer y la alquimia: del laboratorio al símbolo

    OpenAIRE

    Pérez Pariente, Joaquín; Pascual Valderrama, Ignacio M.

    2010-01-01

    This work explores the connection between women and alchemy, in particular the women alchemists and the symbolic meaning of woman in alchemical works. The work and life of the following women are reviewed: Mary the Jewish; the alchemical couple in Flamel and Mutus Liber; Martine de Bertereau;Christina of Sweden and, finally, Mary Ann Atwood, active in the second half of XIX century. There is an abundant representation of woman in alchemical documents, symbolizing both laboratory work and theo...

  17. Návrh vhodných strategií pro společnost podnikající ve stavebnictví

    OpenAIRE

    Šnajnarová, Michaela

    2016-01-01

    Bachelor thesis analyzes the current situation and appropriate strategies for the company in the future. The work consists of two main parts. The first part is theo-retical, which is drawn up on the basis of literature. The following practical part consists of ananalysis carried out by the external environment using PEST analysis and Porter's five forces model. Further more, analysis of the internal environment using Porter's value chain, Weckert and financial analysis. Subsequently, the SWOT...

  18. Análisis Epistemológico del Modelo de Aprendizaje Acumulativo de Robert Gagne

    OpenAIRE

    Meza, Anibal; Lazarte, Carmen

    2013-01-01

    The authors review fundamental aspects of Robert Gagné's Leaming Theory, highlighting its philosophical (positivism and pragmatism) and scientific bases (behaviorism and information processing). Using an epistemological framework, these aspects are assessed in terrns of its theoretical and topical validity, as well as its technical efficiency. It is concluded that Gagné's Theory is eclectic and that its scientific contribution is taxonomic. It represents a theoretical model rather than a theo...

  19. 700 miljardit dollarit, tingimusteta / Peter Coy

    Index Scriptorium Estoniae

    Coy, Peter

    2008-01-01

    USA rahandusministri Henry Paulsoni päästeplaanist, millega üritatakse 700 miljardi dollari eest riigi rahandussüsteemi stabiliseerida. Panganduskriisi leevendamise võimalustest. Lisa: Helde käsi... või karm käsi. Vt. samas: Mara Der Hovanesian, Theo Francis, Jessica Silver-Greenberg. Abi neile, kes ennast aitasid; Jane Sasseen. Kõik see ja siis veel kukkuv dollar

  20. Central limit theorems for Sinkhorn divergence between probability distributions on finite spaces and statistical applications

    OpenAIRE

    Bigot, Jérémie; Cazelles, Elsa; Papadakis, Nicolas

    2017-01-01

    The notion of Sinkhorn divergence has recently gained popularity in machine learning and statistics, as it makes feasible the use of smoothed optimal transportation distances for data analysis. The Sinkhorn divergence allows the fast computation of an entropically regularized Wasserstein distance between two probability distributions supported on a finite metric space of (possibly) high-dimension. For data sampled from one or two unknown probability distributions, we derive central limit theo...

  1. Fulltext PDF

    Indian Academy of Sciences (India)

    TECS

    gives a value of about 2 ns for the formation of the local excited state. So, this is the approximate theo- retical estimate of the ultraslow component arising from the co-operative chain melting in the hydration layer. Note that the time required for breaking of the hydrogen bond is much smaller. It is about 10–. 100 ps for a single ...

  2. The Homeland Security Ecosystem: An Analysis of Hierarchical and Ecosystem Models and Their Influence on Decision Makers

    Science.gov (United States)

    2012-12-01

    Intelligence Analysis (Washington DC: CQ Press, 2011), 123. 184 Ropert Bood and Theo Postma, “Scenario Analysis as a Strategic Management Tool” (Groningen...chain. Much of the analysis in this design uses the agency’s strengths, weaknesses, opportunities, and threats ( SWOT ) or SWOT model, to underpin plans...Safari: A Guided Tour through the Wilds of Strategic Management , 1st ed. (New York: Free Press, 1998), 5. 19 Ibid., 24. 20 Ibid., 32. 21 Ibid., 38

  3. Obchodní model podniku v éře Průmyslu 4.0

    OpenAIRE

    Nohejl, Vít

    2017-01-01

    Industry 4.0 is the current trend of automation and increasing digitalization of wide range of processes. This trend brings about a revolution in manufacturing technologies, but also has its challenges that influence the labor market. The thesis introduces the fourth industrial revolution (Industry 4.0) and provides the most important information for its understanding. It also allows to understand the specific characteristics of business models in the digital society and it clarifies the theo...

  4. Investigations on the local structure and g factors for the interstitial ...

    Indian Academy of Sciences (India)

    The corresponding results (Cal.c) are shown in table 1. For comparisons, the theo- retical g factors (Cal.a) based on neglecting the local lattice distortion (i.e., the host structural parameters ρ ≈ 0.091 and δφ ≈ 3.5◦ of interstitial site are adopted) and those (Cal.b) based on neglecting the ligand contributions (i.e., taking ζ = ζ ...

  5. Indonesian Labor Reform Since 1998

    OpenAIRE

    Uwiyono, Aloysius

    2008-01-01

    The development of labor law in the world essentially influenced by the newest models in industrial relations in each county. In general, there are two models, Corporatist Model/Regulatory Model and Contractual Model. The first model frequently meets in the countries whose use the civil law like France, Netherlands, Germany, and Indonesia, while the second model frequently meet in common law countries like the United States of America's, England, Australia, and Malaysia. Based on the two theo...

  6. Social capital of Turkish and Moroccan immigrants in Belgium: determinants of informal social networks

    OpenAIRE

    VAN CRAEN, Maarten; VANCLUYSEN, Kris; ACKAERT, Johan

    2008-01-01

    In the integration discourse it is often said that native Belgians and members of immigrant communities do not know one another, and that immigrant communities withdraw into their own community. Furthermore non-native Belgians with a Turkish and Moroccan background are often considered as one group. But are their respective integration processes similar? In this article we focus on one aspect of the integration process to answer this question: the acquisition of social capital. Using the theo...

  7. A General Instance-Based Learning Framework for Studying Intuitive Decision-Making in a Cognitive Architecture (Open Access, Publisher’s Version)

    Science.gov (United States)

    2014-06-19

    decision theory (Berger, 1985), and quantum probability theory (Busemeyer, Pothos, Franco, & Trueblood, 2011). Similarly, explanations in the 1 rch in...Trueblood, J. S. (2011). A quantum theo- retical explanation for probability judgment errors. Psychological Review, 118(2), 193. Card, S. K., Moran...Staszewski, J., et al. (2013). A functional model of sensemaking in a neu- rocognitive architecture. Computational Intelligence and Neuroscience , http

  8. Analysis of two-party salary negotiations: factos impeding a mutually-beneficial joint agreement

    OpenAIRE

    Lombera, David Carrillo

    2007-01-01

    Business professionals were surveyed to explore both factors associated with negotiation propensity, as well as the strategies used by employees and employers in salary negotiations. The objective is to examine the factors that impede both pasties in reaching a mutually-beneficial joint agreement in salary negotiations. In order to achieve this objective, a review of the negotiations literature was conducted including both. Descriptive literature - present research finding and scientific theo...

  9. Konopná produkce v podmínkách českého trhu

    OpenAIRE

    PUDILOVÁ, Klára

    2015-01-01

    The title of this bachelor work is Production of cannabis in contidions of the Czech Republic. There is describing growing of hemp, hemp production and hemp goods in the Czech Republic. Hemp production was reducing until 2008 in the Czech Republic but in Europe this plant is commonly used in industry. This Bachelor work proposes possibilities of using hemp in the industry. Work is focused of using industrial hemp in non-food and food industry. Bachelor thesis consists of two components - theo...

  10. Impact of UTAUT/UTAUT2 motives on intention to use deal sites

    DEFF Research Database (Denmark)

    Sudzina, Frantisek

    2018-01-01

    Deal sites, in different forms, exist for more than a decade. Although the industry is mature, there is only a limited number of papers investigating deal sites adoption and use from a customer perspective. Most of the research published on the topic is rather exploratory than using existing theo...... performance expectancy was found to significantly influence intention to use deal sites. Considering UTAUT2 motives, besides performance expectancy, also price value, and habit were found to significantly influence intention to use deal sites....

  11. Multi-layered factors influencing the firm's internationalisation strategy: institutions, micro environment, and firm-level capabilities

    OpenAIRE

    2013-01-01

    This thesis investigates the factors influencing the internationalization of firms through a multi-layered analysis grounded in international business. It addresses the following questions. First, in what ways does the institutional environment facilitate or hinder the growth of start-ups? And in what ways does institutional diversity across countries affect internationalizing firms? Second, in light of the variety of internationalization patterns, what modifications are necessary to the theo...

  12. Chinese Men and "Leftover Women" : How do Chinese Men Position Themselves in Relation to the Concept of Labelling Women as "Leftover"?

    OpenAIRE

    Uddsten, Veronica

    2016-01-01

    In recent years there has been a resurgence of gender inequality in China. Today, women are pressured to get married by the state and their social surroundings, as they told if they remain unmarried and have the "three highs"; high age, education and salary, they will become leftovers on the marriage market. Previous research on the concept of labelling women as "leftover" has 4 shown that labelling women as "leftover" can have several different negative impacts. In this thesis, both the theo...

  13. NHRC (Naval Health Research Center) Report for 1979

    Science.gov (United States)

    1979-01-01

    Profession and Maintaining an Optimistic Definition of the Situation; and (V) Developing Self -reliance and Self - esteem . The secondary factor analysis of...reliance and Self - esteem . Theo- retical implications of these findings are discussed. 79-4 Pugh, WM & EKE Gunderson (ZF51.524.002-5021) Environmental...Florida "The Relationship Between Heart Rate and Aerobic Capacity in Individuals Engaged in Underwater Activities" (Drs. Neuman, Moser & Pruett) "Stres4

  14. A Practical Approach to Cultural Insight

    Science.gov (United States)

    2010-09-01

    elderly parents? ● Gender roles. How rigid are they? ● What are the roles of the elderly? Baharak Bazaar vegetable trader Faiz Mohammad (left) has...believe conspiracy theories . Most humans feel the appeal of conspiracy theo- ries. In some societies, this is exaggerated to the point that people...Public art. How common? What kinds? – Literary traditions? – Major subjects? What is the art about? What’s important? – How important do people

  15. Digital gaming expertise:negotiating gaming capital and gender within the context of gamers' daily lives

    OpenAIRE

    Toft-Nielsen, Claus

    2014-01-01

    In a digitally saturated environment digital media users of all kinds, engaged in different areas of activity, are increasingly categorized in terms of their ability to appropriate and use digital media – they are regarded as non-users, experts, natives, or literates for instance. Within communication and game studies there are multiple understandings of how digital expertise is expressed and performed, and subsequently how these expressions and performances can be valued, understood and theo...

  16. Trinity and mission: challenges to a reformed witness in Africa today

    OpenAIRE

    Rian Venter

    2004-01-01

    The paper explores the possibility of a Reformed missional response to the present moment in Southern Africa. The basic thesis is that two of the Reformed tenets� � theo-centrism and intellectual reflection as part of a holistic vocation � are especially suitable for a missional response, but stand in need of radicalising. The renaissance of trinitarian thinking and the ramifications for missiology and ecclesiology are discussed. Finally attention is given to quality improvement of theologica...

  17. A large strain radial consolidation theory for soft clays improved by vertical drains\\ud

    OpenAIRE

    Geng, Xueyu; Yu, Hai-sui

    2017-01-01

    A system of vertical drains with combined vacuum and surcharge preloading is an effective 10 solution for promoting radial flow, accelerating consolidation. However, when a mixture of soil and\\ud 11 water is deposited at a low initial density, a significant amount of deformation or surface settlement 12 occurs. Therefore, it is necessary to introduce large strain theory, which has been widely used to manage\\ud 13 dredged disposal sites in one-dimensional theory, into radial consolidation theo...

  18. «La prosopographie: une nouvelle voie pour l’histoire de la Franc-maçonnerie»

    Directory of Open Access Journals (Sweden)

    Éric Saunier

    2009-01-01

    Full Text Available Prosopography has played a very important role in the methodological renewal of French Masonic historiography over the last twenty years; however it has received little theo retical attention from historians of Freemasonry. In this article, is employed an epistemol ogical approach to study the historical treatment of Masonic facts. This type of reflecti on is necessary in the understanding of the history of Freemasonry because it proves to be much more effective than contemporary methods.

  19. The Influence of Education and Experience Upon Contextual and Task Performance in Warehouse Operations

    Science.gov (United States)

    2016-09-01

    has been used to assess high mobility multipurpose wheeled vehicle (HMMWV) rollovers. He attributes the high number of rollovers in 2004 to the...O. and Tartaglia, R. (2010), “Are hospitals becoming high reliability organizations?”, Applied Ergonomics , Elsevier, Vol. 41 No. 5, pp. 713– 718...theory as a framework for analyzing and redesigning work”, Ergonomics , Taylor & Francis, Vol. 43 No. 7, pp. 960–974. 152 Epple, D., Argote, L. and

  20. Theoretical Model of Engagement in the Context of Brand Communities

    OpenAIRE

    Flávia D\\u2019albergaria Freitas; Victor Manoel Cunha de Almeida

    2017-01-01

    This essay proposes to refine the concept of consumer engagement in the context of brand communities. A comprehensive review of studies addressing the phenomenon of brand community was made. This paper follows the tradition of Marketing Research and Consumer Behavior, more specifically the perspective of cognitive psychology. The main theoretical foundation of the study is the Social Identity Theory (SIT), also incorporating relevant contributions from the perspective of Consumer Culture Theo...

  1. Highest and best use of agricultural land in multifunctional land market evidence from South Africa

    CSIR Research Space (South Africa)

    Reed, L

    2010-01-01

    Full Text Available land in a multifunctional land market – evidence from South Africa DEPARTMENT of AGRICULTURE Provincial Government of the Western Cape Lozelle Reed and Theo Kleynhans 16th Annual Pacific Rim Real Estate Society Conference, Wellington, New... to maximise understanding Qualitative data collection • 16 “lifestyle” cases nationwide in South Africa • Variety in valuer, area, enterprises • Interviews with all parties (buyer, seller, estate agent, valuer) • Valuation reports • 64 participants...

  2. Pozdní rodičovství a jeho vliv na výchovný styl

    OpenAIRE

    Doležalová, Hana

    2013-01-01

    The thesis discusses the late parenthood and its impact on parenting style. The thesis is conceived as a theoretical and empirical studies. The theoretical part focuses on the phenomenon of the late parenthood, its definition and selected aspects. Defines voluntary and involuntary late parenthood and describes the current situation in the society in the Czech Republic. Describes the health risks associated with the late parenting, from conception until birth. Furthermore depicts selected theo...

  3. Výchova a vývoj dětí v lesbické rodině

    OpenAIRE

    Sedláčková, Anna

    2010-01-01

    The thesis deals with topic of lesbian families and specifics of children from these families. The theoretical part of the work is supported by studies from the USA and the Great Britain in particular. This part is focused on definition of homoparental family and its types, specifics of upbringing and relations within. It also deals with the topic of coming-out. It gives account of the family roles - biological mother, biological father, social mother / stepmother. The second half of the theo...

  4. Rate coefficients for hydrogen abstraction reaction of pinonaldehyde ...

    Indian Academy of Sciences (India)

    Abstract. The kinetics of the reaction between pinonaldehyde (C10H16O2) and Cl atom were studied using high level ab initio G3(MP2) and DFT based MPWB1K/6-31+G(d) and MPW1K/6-31+G(d) levels of theo- ries coupled with Conventional Transition State Theory in the temperature range between 200 and 400 K. The.

  5. Implementation of secondary fracture prevention services after hip fracture: a qualitative study using extended Normalization Process Theory

    OpenAIRE

    Drew, Sarah; Judge, Andrew; May, Carl; Farmer, Andrew; Cooper, Cyrus; Javaid, M Kassim; Gooberman-Hill, Rachael

    2015-01-01

    Background National and international guidance emphasizes the need for hospitals to have effective secondary fracture prevention services, to reduce the risk of future fractures in hip fracture patients. Variation exists in how hospitals organize these services, and there remain significant gaps in care. No research has systematically explored reasons for this to understand how to successfully implement these services. The objective of this study was to use extended Normalization Process Theo...

  6. Prospects for testing Lorentz and CPT symmetry with antiprotons.

    Science.gov (United States)

    Vargas, Arnaldo J

    2018-03-28

    A brief overview of the prospects of testing Lorentz and CPT symmetry with antimatter experiments is presented. The models discussed are applicable to atomic spectroscopy experiments, Penning-trap experiments and gravitational tests. Comments about the sensitivity of the most recent antimatter experiments to the models reviewed here are included.This article is part of the Theo Murphy meeting issue 'Antiproton physics in the ELENA era'. © 2018 The Author(s).

  7. The role of conversational maxims, implicature and presupposition in the creation of humour: an analysis of Woody Allen’s anything else

    OpenAIRE

    Nieto Álvaro, Ramiro

    2011-01-01

    Humour is becoming the shelter of a dehumanised society that aspires to find happiness in different areas of daily life. This paper focuses on the analysis of humour in a specific realm, cinema, from a pragmatic perspective; the concrete movie studied is Woody Allen’s Anything Else. The analysis will cover various pragmatic concepts such as implicature, conversational maxims and presupposition, which will be approached in combination with rhetorical figures and taking into account humour theo...

  8. Fulltext PDF

    Indian Academy of Sciences (India)

    not possible to keep other governing parameters con- stant for these ... one governing parameter keeping others constant theo- retically in the ..... such a trend (where. = shorter Ni–N bond distance – longer Ni–N bond distance) has been observed experi- mentally in 1 ( is −0.12 Å and J = 5.0 cm−1), 2 ( is −0.06 Å and J ...

  9. Consumers' willingness to buy food via the Internet: A review of the litterature and a model for future research

    OpenAIRE

    Ramus, Kim Bjarne; Grunert, Klaus G.

    2004-01-01

    In the first part of the paper, existing studies on consumer propensity to buy via the Internet are reviewed in an attempt to shed light on factors explaining consumer willingness to buy food via the Internet. Following a model by Sindhav and Balazs (1999), determinants relating to medium, product, consumer, firm and environment are distinguished. In order to draw the various results together and provide a coherent framework for future research, we then propose a model which combines the Theo...

  10. CONSUMERS’ WILLINGNESS TO BUY FOOD VIA THE INTERNET: A REVIEW OF THE LITTERATURE AND A MODEL FOR FUTURE RESEARCH

    OpenAIRE

    Ramus, Kim Bjarne; Grunert, Klaus G.

    2004-01-01

    In the first part of the paper, existing studies on consumer propensity to buy via the Internet are reviewed in an attempt to shed light on factors explaining consumer willingness to buy food via the Internet. Following a model by Sindhav and Balazs (1999), determinants relating to medium, product, consumer, firm and environment are distinguished. In order to draw the various results together and provide a coherent framework for future research, we then propose a model which combines the Theo...

  11. Silke Forlag : Building Brand Equtiy for a Publisher

    OpenAIRE

    Westby, Hans-Henrik Palm

    2014-01-01

    The purpose of this master thesis is to contribute to the knowledge about increasing the brand equity for a publisher. More specifically the thesis emphases on the communication the publisher sends out to consumers, in order to get the consumer to be aware of the publisher when buying books. Making the consumer notice the publisher and their values and not only the author or the book itself. Silke Forlag has been chosen as the publisher to be analyzed for this case. The theo...

  12. Next-to-next-leading order correction to 3-jet rate and event-shape ...

    Indian Academy of Sciences (India)

    The coupling constant, αs, was measured by two different methods: first by employing the three-jet observables. Combining all the data, the value of as at next-to-next leading order (NNLO) was determined to be 0.117 ± 0.004(hard) ± 0.006(theo). Secondly, from the event-shape distributions, the strong coupling constant, αs ...

  13. Analýza potenciálu SaaS v malých a středních podnicích

    OpenAIRE

    Pavlů, Pavel

    2008-01-01

    This paper analyses potential of Software as a Service (SaaS) model in small and medium enterprises (SME). SaaS model is rapidly expanding trend between software delivery models. The first chapter describes evolution of software delivery models, which peaks in the most recent "Software as a Service" model. It analyses key features of SaaS in qualitative, technological and legal dimensions. The first chapter also mentions assesment methods for IT investments. This chapter introduces basic theo...

  14. Behavioral Science in the Army: A Corporate History of the Army Research Institute

    Science.gov (United States)

    1988-06-01

    H. Hiller (Training Research) . These three laboratories and a basic research office carry out ARI research. Three scientific coordination offices...Rosenberger E. Kenneth Karcher Howard L. Roy Aaron Katz Edward L. Rundquist Carol Kehr Eva Russell Frank Kellmayer Robert Sadacca Samuel H. King Taube Sass...Evans Allyn Hertzbach Beatrice J. Farr Otto H. Heuckroth Francis M. Farrell Jack M. Hicks John P. Farrell Jack H. Hiller Theo-Dric Feng Patty Hoke

  15. Ontology of Time in Cinema A Deleuzian reading of Still Life and Prince Ehtejab With an emphasis on the concept of Time-Image

    OpenAIRE

    Ali Fath Taheri; Faezeh Jafariyan

    2017-01-01

    Gilles Deleuze, the notable post-modern philosopher, in his two-volume cinematic books Cinema 1: movement-image (1986) and Cinema 2: time-image (1989) recognizes two major periods in history of cinema (classic and modern) in terms of representing movement and time respectively. Referring to various films of modern cinema especially post-war European cinema like Italian neorealism, Cinema2 speaks about the possibility of direct presentation of time in cinematic works. Explaining Deleuze’s theo...

  16. Life-Cycle Finance and the Design of Pension Plans

    OpenAIRE

    Zvi Bodie; Jérôme Detemple; Marcel Rindisbacher

    2009-01-01

    This article reviews recent scientific literature on consumer financial decisions over the life cycle, outlining its implications for the design of pension plans. It begins with a review of advances in the theory of rational financial planning and wealth management. It then summarizes the recent empirical literature on the actual behavior of households regarding saving, investing, and insuring their consumption in old age. Finally, it briefly comments on the practical implications of the theo...

  17. Apparent inconsistent theophylline absorption from sustained release capsules.

    Science.gov (United States)

    Uden, D L; Schaber, D E; Wyatt, R A

    1987-06-01

    Sustained release theophylline products can improve compliance and symptom control in children with asthma. This study examines theophylline serum concentration monitoring in pediatric patients. Fifteen children with documented asthma were randomized to receive either Slo-bid Gyrocaps or Theo-dur Sprinkle for 1 month, and then crossed over to the other product. On the last day of each study period, theophylline serum concentrations were obtained prior to the morning dose and 4 hours later. In two patients receiving Theo-dur Sprinkle and six with Slo-bid Gyrocaps, the 4-hour serum concentration was lower than the pre-dose concentration. The change between the pre-dose and post-dose serum concentrations for Theo-dur Sprinkle ranged from a decrease of 2.8 mg/L to an increase of 4.9 mg/L, and, for Slo-bid Gyrocaps, from a decrease of 4.6 mg/L to an increase of 10.5 mg/L. The inconsistent theophylline absorption with each product makes dosage adjustment difficult.

  18. Measurement of the inclusive charmless semileptonic branching ratio of b mesons and determination of |v(ub)|

    International Nuclear Information System (INIS)

    Aubert, B.

    2004-01-01

    We report a measurement of the inclusive charmless semileptonic branching fraction of B mesons in a sample of 89x10(6) B(b) over bar events recorded with the BABAR detector at the Upsilon(4S) resonance. Events are selected by fully reconstructing the decay of one B meson and identifying a charged lepton from the decay of the other B meson. The number of signal events is extracted from the mass distribution of the hadronic system accompanying the lepton and is used to determine the ratio of branching fractions B((B) over bar --> X(u)l (v) over bar)/B((B) over bar --> Xl (v) over bar) = [2.06 +/- 0.25(stat) +/- 0.23(syst) +/- 0.36(theo)] x 10(-2). Using the measured branching fraction for inclusive semileptonic B decays, we find B((B) over bar --> X(u)l (V) over bar) = [2.24+/-0.27(stat) +/- 0.26(syst) +/- 0.39(theo)] x 10(-3) and derive the Cabibbo-Kobayashi-Maskawa matrix element parallel toV(ub)parallel to = [4.62 +/- 0.28(stat) +/- 0.27(syst) +/- 0.48(theo)] x 10(-3)

  19. Quantum limits of Eisenstein series and scattering states

    DEFF Research Database (Denmark)

    Petridis, Y.N.; Raulf, N.; Risager, Morten S.

    2013-01-01

    We identify the quantum limits of scattering states for the modular surface. This is obtained through the study of quantum measures of non-holomorphic Eisenstein series away from the critical line. We provide a range of stability for the quantum unique ergodicity theorem of Luo and Sarnak....

  20. Erratum to "Quantum Limits of Eisenstein Series and Scattering States''

    DEFF Research Database (Denmark)

    Petridis, Y.N.; Raulf, N.; Risager, Morten S.

    2013-01-01

    We identify the quantum limits of scattering states for the modular surface. This is obtained through the study of quantum measures of non-holomorphic Eisenstein series away from the critical line. We provide a range of stability for the quantum unique ergodicity theorem of Luo and Sarnak. © Cana...

  1. A remark on the Lifshitz tail for Schrödinger operator with random ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Abstract. In this note, we consider the Lifshitz singularity for Schrödinger opera- tor with ergodic random magnetic field. A key estimate is an energy bound for mag- netic Schrödinger operators as discussed in Nakamura [8]. Here we remove a technical assumption in [8], namely, the uniform boundedness of the magnetic ...

  2. Author Details

    African Journals Online (AJOL)

    Ricker, Werner J. Vol 36, No 2 (2013) - Articles Montel resolvents and uniformly mean ergodic semigroups of linear operators. Abstract. ISSN: 1607-3606. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of ...

  3. Dynamics of a stochastic HIV-1 infection model with logistic growth

    Science.gov (United States)

    Jiang, Daqing; Liu, Qun; Shi, Ningzhong; Hayat, Tasawar; Alsaedi, Ahmed; Xia, Peiyan

    2017-03-01

    This paper is concerned with a stochastic HIV-1 infection model with logistic growth. Firstly, by constructing suitable stochastic Lyapunov functions, we establish sufficient conditions for the existence of ergodic stationary distribution of the solution to the HIV-1 infection model. Then we obtain sufficient conditions for extinction of the infection. The stationary distribution shows that the infection can become persistent in vivo.

  4. An Extreme-Value Analysis of the LIL for Brownian Motion

    OpenAIRE

    Khoshnevisan, Davar; Levin, David; Shi, Zhan

    2005-01-01

    We use excursion theory and the ergodic theorem to present an extreme-value analysis of the classical law of the iterated logarithm (LIL) for Brownian motion. A simplified version of our method also proves, in a paragraph, the classical theorem of Darling and Erdős (1956).

  5. A remark on the Lifshitz tail for Schrödinger operator with random ...

    Indian Academy of Sciences (India)

    Abstract. In this note, we consider the Lifshitz singularity for Schrödinger operator with ergodic random magnetic field. A key estimate is an energy bound for magnetic Schrödinger operators as discussed in Nakamura [8]. Here we remove a technical assumption in [8], namely, the uniform boundedness of the magnetic field.

  6. The Green-Kubo formula and the Onsager reciprocity relations in quantum statistical mechanics

    CERN Document Server

    Jaksic, V; Pillet, C

    2005-01-01

    We study linear response theory in the general framework of algebraic quantum statistical mechanics and prove the Green-Kubo formula and the Onsager reciprocity relations for heat fluxes generated by temperature differentials. Our derivation is axiomatic and the key assumptions concern ergodic properties of non-equilibrium steady states.

  7. Variation in the Input: A Case Study of Manner Class Frequencies

    Science.gov (United States)

    Daland, Robert

    2013-01-01

    What are the sources of variation in the input, and how much do they matter for language acquisition? This study examines frequency variation in manner-of-articulation classes in child and adult input. The null hypothesis is that segmental frequency distributions of language varieties are unigram (modelable by stationary, ergodic processes), and…

  8. Siva R Athreya | Speakers | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Dense graph limits under respondent-driven sampling View Presentation. Certain respondent-driven sampling procedures on dense graphs will be considered. It will be shown that if the sequence of the vertex-sets is ergodic, then the limiting graph can be expressed in terms of the original dense graph via a transformation ...

  9. Dense graph limits under respondent-driven sampling

    Indian Academy of Sciences (India)

    Siva Athreya

    Sub-graph count (fingerprints). Source: IUPUI Network Sampling course. Page 15. Aim and Result. • Motivation: provide a rigorous framework for Respondent. Driven Sampling on dense graphs. • Theorem : (in words). Limit of a dense graph sequence constructed via R.D.S., where the sequence of the vertex-sets is ergodic, ...

  10. Nadkarni, Prof. Mahendra Ganpatrao

    Indian Academy of Sciences (India)

    Fellow Profile. Elected: 1989 Section: Mathematical Sciences. Nadkarni, Prof. Mahendra Ganpatrao Ph.D. (Brown), FNA. Date of birth: 17 January 1939. Specialization: Ergodic Theory and Commutative Harmonic Analysis Address: Emeritus Professor, Department of Mathematics, University of Bombay, Vidyanagari, Kalina, ...

  11. Poisson Autoregression

    DEFF Research Database (Denmark)

    Fokianos, Konstantinos; Rahbek, Anders Christian; Tjøstheim, Dag

    2009-01-01

    In this article we consider geometric ergodicity and likelihood-based inference for linear and nonlinear Poisson autoregression. In the linear case, the conditional mean is linked linearly to its past values, as well as to the observed values of the Poisson process. This also applies to the condi......In this article we consider geometric ergodicity and likelihood-based inference for linear and nonlinear Poisson autoregression. In the linear case, the conditional mean is linked linearly to its past values, as well as to the observed values of the Poisson process. This also applies...... to the conditional variance, making possible interpretation as an integer-valued generalized autoregressive conditional heteroscedasticity process. In a nonlinear conditional Poisson model, the conditional mean is a nonlinear function of its past values and past observations. As a particular example, we consider...... ergodicity proceeds via Markov theory and irreducibility. Finding transparent conditions for proving ergodicity turns out to be a delicate problem in the original model formulation. This problem is circumvented by allowing a perturbation of the model. We show that as the perturbations can be chosen...

  12. Plasma surface interactions in controlled fusion devices

    Energy Technology Data Exchange (ETDEWEB)

    Ghendrih, Ph.; Becoulet, M.; Costanzo, L. [and others

    2000-07-01

    This report brings together all the contributions of EURATOM/CEA association to the 14. international conference on plasma surface interactions in controlled fusion devices. 24 papers are presented and they deal mainly with the ergodic divertor and the first wall of Tore-supra tokamak.

  13. The three-body problem and equivariant Riemannian geometry

    Science.gov (United States)

    Alvarez-Ramírez, M.; García, A.; Meléndez, J.; Reyes-Victoria, J. G.

    2017-08-01

    We study the planar three-body problem with 1/r2 potential using the Jacobi-Maupertuis metric, making appropriate reductions by Riemannian submersions. We give a different proof of the Gaussian curvature's sign and the completeness of the space reported by Montgomery [Ergodic Theory Dyn. Syst. 25, 921-947 (2005)]. Moreover, we characterize the geodesics contained in great circles.

  14. On index-2 linear implicit difference equations

    NARCIS (Netherlands)

    Nguyen Huu Du, [No Value; Le Cong Loi, [No Value; Trinh Khanh Duy, [No Value; Vu Tien Viet, [No Value

    2011-01-01

    This paper deals with an index-2 notion for linear implicit difference equations (LIDEs) and with the solvability of initial value problems (IVPs) for index-2 LIDEs. Besides, the cocycle property as well as the multiplicative ergodic theorem of Oseledets type are also proved. (C) 2010 Elsevier Inc.

  15. Ghosh, Prof. Anish

    Indian Academy of Sciences (India)

    Fellow Profile. Elected: 2018 Section: Mathematical Sciences. Ghosh, Prof. Anish Ph.D. (Brandeis). Date of birth: 25 December 1979. Specialization: Ergodic Theory, Lie Groups, Number Theory Address: School of Mathematics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, Maharashtra

  16. Microcanonical simulation of Ising systems

    International Nuclear Information System (INIS)

    Bhanot, G.; Neuberger, H.

    1984-01-01

    Numerical simulations of the microcanonical ensemble for Ising systems are described. We explain how to write very fast algorithms for such simulations, relate correlations measured in the microcanonical ensemble to those in the canonical ensemble and discuss criteria for convergence and ergodicity. (orig.)

  17. Limit theorems for stationary increments Lévy driven moving averages

    DEFF Research Database (Denmark)

    Basse-O'Connor, Andreas; Lachièze-Rey, Raphaël; Podolskij, Mark

    of the kernel function g at 0. First order asymptotic theory essentially comprise three cases: stable convergence towards a certain infinitely divisible distribution, an ergodic type limit theorem and convergence in probability towards an integrated random process. We also prove the second order limit theorem...

  18. Spectral analysis of linear relations and degenerate operator semigroups

    International Nuclear Information System (INIS)

    Baskakov, A G; Chernyshov, K I

    2002-01-01

    Several problems of the spectral theory of linear relations in Banach spaces are considered. Linear differential inclusions in a Banach space are studied. The construction of the phase space and solutions is carried out with the help of the spectral theory of linear relations, ergodic theorems, and degenerate operator semigroups

  19. Stationary distribution of a stochastic SIS epidemic model with double diseases and the Beddington-DeAngelis incidence

    Science.gov (United States)

    Liu, Qun; Jiang, Daqing

    2017-08-01

    In this paper, a stochastic Susceptible-Infected-Susceptible (SIS) epidemic model with double diseases and the Beddington-DeAngelis incidence is proposed and studied. Sufficient conditions for the existence of an ergodic stationary distribution of the positive solutions to the model are obtained via the Lyapunov function method. The existence of stationary distribution implies stochastic stability to some extent.

  20. Stationary distribution of a stochastic SIS epidemic model with double diseases and the Beddington-DeAngelis incidence.

    Science.gov (United States)

    Liu, Qun; Jiang, Daqing

    2017-08-01

    In this paper, a stochastic Susceptible-Infected-Susceptible (SIS) epidemic model with double diseases and the Beddington-DeAngelis incidence is proposed and studied. Sufficient conditions for the existence of an ergodic stationary distribution of the positive solutions to the model are obtained via the Lyapunov function method. The existence of stationary distribution implies stochastic stability to some extent.

  1. The division of plasma physics

    International Nuclear Information System (INIS)

    Evans, T.E.; Guilhem, D.; Klepper, C.C.

    1990-07-01

    The investigations presented in the 31th meeting on plasma physics were: the main results and observations during the ergodic divertor experiments in Tore Supra tokamak; the modifications of power scrape-off-length and power deposition during various configurations in Tore Supra plasmas; the results of pressure measurements and particle fluxes in the Tore Supra pump limiter

  2. Proceedings – Mathematical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The notion of ergodicity of a measure preserving group of automorphisms of the probability space , is used to prove the almost sure independence of the Arveson spectrum S p ( T ( ) ) of T t ( ) . As a consequence, for any family of ( T ( ) , ) -KMS states {ρ()}, the spectrum of the generator of the group of unitaries ...

  3. Semiclassical computations of energy levels

    International Nuclear Information System (INIS)

    Bogomolny, E.; Schmit, C.

    1992-09-01

    Different methods of semiclassical calculations of energy levels of two-dimensional ergodic models are discussed and compared. Special attention is given to the calculation of the dynamical zeta function via the Riemann-Siegel relations. (author) 52 refs.; 15 figs

  4. Proceedings – Mathematical Sciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Abstract. In this note, we consider the Lifshitz singularity for Schrödinger operator with ergodic random magnetic field. A key estimate is an energy bound for magnetic Schrödinger operators as discussed in Nakamura [8]. Here we remove a technical assumption in [8], namely, the uniform boundedness of the magnetic field.

  5. Dynamics via measurability

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Generators f for σ -algebras can be used to view the dynamics of an invertible measurable transformation T in terms of the range values of f ∘ T . Such generators are the norm rather than the exception. Related measurable and quantitative methods of estimating a function from the behavior of ergodic averages are also discussed.

  6. On optimality of the empirical distribution function for the estimation ...

    African Journals Online (AJOL)

    In this work we present some results on the optimality of the empirical distribution function as estimator of the invariant distribution function of an ergodic diffusion process. The results presented were obtained in different previous works under conditions that are are rewritten in a unified form that make comparable those ...

  7. Strong approximations and sequential change-point analysis for diffusion processes

    DEFF Research Database (Denmark)

    Mihalache, Stefan-Radu

    2012-01-01

    In this paper ergodic diffusion processes depending on a parameter in the drift are considered under the assumption that the processes can be observed continuously. Strong approximations by Wiener processes for a stochastic integral and for the estimator process constructed by the one...

  8. Thermalization in integrable models and conformal field theories

    Indian Academy of Sciences (India)

    Gautam Mandal TIFR, Mumbai

    Introduction. Critical quench: model building. Quantum Ergodicity and integrability. Relaxation rates. Holography. Thermalization in gravity: gravitational collapse. No hair theorem: different forms and descriptions of matter, collapse into a black hole characterized by only the to- tal mass (and angular momentum and charge) ...

  9. Parametric inference for stochastic differential equations: a smooth and match approach

    NARCIS (Netherlands)

    Gugushvili, S.; Spreij, P.

    2012-01-01

    We study the problem of parameter estimation for a univariate discretely observed ergodic diffusion process given as a solution to a stochastic differential equation. The estimation procedure we propose consists of two steps. In the first step, which is referred to as a smoothing step, we smooth the

  10. Parameter estimates for linear partial differential equations with fractional boundary noise

    Czech Academy of Sciences Publication Activity Database

    Maslowski, Bohdan; Pospíšil, J.

    2007-01-01

    Roč. 7, č. 1 (2007), s. 1-20 ISSN 1526-7555 R&D Projects: GA ČR GA201/07/0237 Institutional research plan: CEZ:AV0Z10190503 Keywords : parameter identification * ergodicity * stochastic partial differential equations Subject RIV: BA - General Mathematics

  11. Waveform Design for Multimedia Airborne Networks: Robust Multimedia Data Transmission in Cognitive Radio Networks

    Science.gov (United States)

    2011-03-01

    are in good agreement with the Monte Carlo simulation results. Moreover, the actual ergodic capacity is slightly closer to the lower...detectors," Proc. 2nd IEEE Symp. New Frontiers in Dynamic Spectrum Access Networks, Dublin, Ireland, 276-282 (2007). [25] M. Ghozzi, F. Marx , M

  12. Markov Chain Monte Carlo Methods

    Indian Academy of Sciences (India)

    ter of the 20th century, due to rapid developments in computing technology ... early part of this development saw a host of Monte ... These iterative. Monte Carlo procedures typically generate a random se- quence with the Markov property such that the Markov chain is ergodic with a limiting distribution coinciding with the ...

  13. Kosambi, the Mathematician

    Indian Academy of Sciences (India)

    S G Dani is a Distinguished. Professor at the Tata. Institute of Fundamental. Research, Mumbai. He obtained his bachelor's, master's and PhD degrees from the University of. Mumbai. His areas of interest are dynamics and ergodic theory of flows on homogeneous spaces, applications to diophantine approximation ...

  14. Dynamic magnetoconductance fluctuations and oscillations in mesoscopic wires and rings

    DEFF Research Database (Denmark)

    Liu, D. Z.; Hu, Ben Yu-Kuang; Stafford, C. A.

    1994-01-01

    wire, we observe ergodic behavior in the dynamic conductance fluctuations. At low omega, the real part of the conductance fluctuations is essentially given by the dc universal conductance fluctuations while the imaginary part increases linearly from zero, but for omega greater than the Thouless energy...

  15. The spectral method and the central limit theorem for general Markov chains

    Science.gov (United States)

    Nagaev, S. V.

    2017-12-01

    We consider Markov chains with an arbitrary phase space and develop a modification of the spectral method that enables us to prove the central limit theorem (CLT) for non-uniformly ergodic Markov chains. The conditions imposed on the transition function are more general than those by Athreya-Ney and Nummelin. Our proof of the CLT is purely analytical.

  16. A limitation on Bell's inequality

    International Nuclear Information System (INIS)

    Buonomano, V.

    1978-01-01

    It is shown that Bell's Inequality does not characterize all local hidden variable explanations of the polarization correlation experiments. If one considers theories in which a single polarization measurement is not independent of previous particle-polarizer interactions then it is possible to manufacture local hidden variable theories which agree with quantum mechanics for any of the experiments performed to date. A relevant property here is ergodicity, and we can say that Bell's Inequality characterizes all ergodic local hidden variable theories (i.e. all local theories that give the same time and ensemble average) but not all non-ergodic local hidden variable theories. It is further shown that the most physically reasonable class of non-ergodic local hidden variable theories must also satisfy Bell's Inequality. It might be concluded from this article that if one insists on believing in both local hidden variable theories and the polarization correlation experiments supporting quantum mechanics then one must also believe in the existence of a field, medium or ether that permeates space and has relatively stable states (memory)

  17. Associateship | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Fellowship; Associateship. Associate Profile. Period: 1993–1998. Shah, Dr Nimish A. Date of birth: 4 February 1967. Specialization: Ergodic Theory Address during Associateship: School of Mathematics, Tata Inst. of Fundamental Research, Homi Bhabha Road, Mumbai 400 005. YouTube; Twitter; Facebook; Blog ...

  18. Stationary stochastic processes theory and applications

    CERN Document Server

    Lindgren, Georg

    2012-01-01

    Some Probability and Process BackgroundSample space, sample function, and observablesRandom variables and stochastic processesStationary processes and fieldsGaussian processesFour historical landmarksSample Function PropertiesQuadratic mean propertiesSample function continuityDerivatives, tangents, and other characteristicsStochastic integrationAn ergodic resultExercisesSpectral RepresentationsComplex-valued stochastic processesBochner's theorem and the spectral distributionSpectral representation of a stationary processGaussian processesStationary counting processesExercisesLinear Filters - General PropertiesLinear time invariant filtersLinear filters and differential equationsWhite noise in linear systemsLong range dependence, non-integrable spectra, and unstable systemsThe ARMA-familyLinear Filters - Special TopicsThe Hilbert transform and the envelopeThe sampling theoremKarhunen-Loève expansionClassical Ergodic Theory and MixingThe basic ergodic theorem in L2Stationarity and transformationsThe ergodic th...

  19. Skyshine analysis using various nuclear data files

    International Nuclear Information System (INIS)

    Zharkov, V.P.; Dikareva, O.F.; Kartashev, I.A.; Kiselev, A.N.; Nomura, Y.; Tsubosaka, A.

    2000-01-01

    The calculations of the spacial distributions of dose rate for neutron and secondary photons, thermal neutron fluxes and space-energy distributions of neutron and photons near the air-ground interface were performed by MCNP and DORT codes. Different nuclear data files were used (ENDF/B-IV, ENDF/B-VI, FENDL-2, JENDL-3.2). Either the standard pointwise libraries (MCNP) or special libraries prepared by NJOY code from ENDF/B and others' files were used. Prepared multigroup coupled neutron and photon cross sections libraries for DORT code had CASK-40 group energy structures. The libraries contain pointwise or multigroup cross sections data for all elements included in the atmosphere and ground composition. The validation of the calculated results was performed with using the experimental data obtained for the series of measurements at RA reactor. (author)

  20. Unresolved resonance self shielding calculation: causes and importance of discrepancies

    International Nuclear Information System (INIS)

    Ribon, P.; Tellier, H.

    1986-09-01

    To compute the self shielding coefficient, it is necessary to know the point-wise cross-sections. In the unresolved resonance region, we do not know the parameters of each level but only the average parameters. Therefore we simulate the point-wise cross-section by random sampling of the energy levels and resonance parameters with respect to the Wigner law and the X 2 distributions, and by computing the cross-section in the same way as in the resolved regions. The result of this statistical calculation obviously depends on the initial parameters but also on the method of sampling, on the formalism which is used to compute the cross-section or on the weighting neutron flux. In this paper, we will survey the main phenomena which can induce discrepancies in self shielding computations. Results are given for typical dilutions which occur in nuclear reactors. 8 refs