Completely regular fuzzifying topological spaces
A. K. Katsaras
2005-12-01
Full Text Available Some of the properties of the completely regular fuzzifying topological spaces are investigated. It is shown that a fuzzifying topology ÃÂ„ is completely regular if and only if it is induced by some fuzzy uniformity or equivalently by some fuzzifying proximity. Also, ÃÂ„ is completely regular if and only if it is generated by a family of probabilistic pseudometrics.
Regularization methods in Banach spaces
Schuster, Thomas; Hofmann, Bernd; Kazimierski, Kamil S
2012-01-01
Regularization methods aimed at finding stable approximate solutions are a necessary tool to tackle inverse and ill-posed problems. Usually the mathematical model of an inverse problem consists of an operator equation of the first kind and often the associated forward operator acts between Hilbert spaces. However, for numerous problems the reasons for using a Hilbert space setting seem to be based rather on conventions than on an approprimate and realistic model choice, so often a Banach space setting would be closer to reality. Furthermore, sparsity constraints using general Lp-norms or the B
REGULAR RELATIONS AND MONOTONE NORMAL ORDERED SPACES
XU XIAOQUAN; LIU YINGMING
2004-01-01
In this paper the classical theorem of Zareckii about regular relations is generalized and an intrinsic characterization of regularity is obtained. Based on the generalized Zareckii theorem and the intrinsic characterization of regularity, the authors give a characterization of monotone normality of ordered spaces. A new proof of the UrysohnNachbin lemma is presented which is quite different from the classical one.
Regular Submanifolds in Conformal Space Qnp
Changxiong NIE; Chuanxi WU
2012-01-01
The authors study the regular submanifolds in the conformal space Qnp and introduce the submanifold theory in the conformal space Qnp.The first variation formula of the Willmore volume functional of pseudo-Riemannian submanifolds in the conformal space Qnp is given.Finally,the conformal isotropic submanifolds in the conformal space Qnp are classified.
Regular Decompositions for H(div) Spaces
Kolev, Tzanio [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Center for Applied Scientific Computing; Vassilevski, Panayot [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Center for Applied Scientific Computing
2012-01-01
We study regular decompositions for H(div) spaces. In particular, we show that such regular decompositions are closely related to a previously studied “inf-sup” condition for parameter-dependent Stokes problems, for which we provide an alternative, more direct, proof.
The moduli space of regular stable maps
Robbin, Joel; Salamon, Dietmar; 10.1007/s00209-007-0237-x
2012-01-01
The moduli space of regular stable maps with values in a complex manifold admits naturally the structure of a complex orbifold. Our proof uses the methods of differential geometry rather than algebraic geometry. It is based on Hardy decompositions and Fredholm intersection theory in the loop space of the target manifold.
Least square regularized regression in sum space.
Xu, Yong-Li; Chen, Di-Rong; Li, Han-Xiong; Liu, Lu
2013-04-01
This paper proposes a least square regularized regression algorithm in sum space of reproducing kernel Hilbert spaces (RKHSs) for nonflat function approximation, and obtains the solution of the algorithm by solving a system of linear equations. This algorithm can approximate the low- and high-frequency component of the target function with large and small scale kernels, respectively. The convergence and learning rate are analyzed. We measure the complexity of the sum space by its covering number and demonstrate that the covering number can be bounded by the product of the covering numbers of basic RKHSs. For sum space of RKHSs with Gaussian kernels, by choosing appropriate parameters, we tradeoff the sample error and regularization error, and obtain a polynomial learning rate, which is better than that in any single RKHS. The utility of this method is illustrated with two simulated data sets and five real-life databases.
Remark on Regularity of Continuous Operators on AL-Spaces
冯勋省; 陈滋利
2004-01-01
Let E and F be Banach lattices. It is known that if every continuous linear operator from E into F is regular, then, under some mild assumptions on E or F, either E is lattice isomorphic to an AL-space or F is lattice isomorphic to an AM-space. Here we present a characterization on an AL-space E such that every bounded linear operator from E into a Banach lattice is regular. A counterexample is also provided, which shows that the results are unexpected even if the domain is an AL-space or the range space is an AM-space.
Semisupervised Support Vector Machines With Tangent Space Intrinsic Manifold Regularization.
Sun, Shiliang; Xie, Xijiong
2016-09-01
Semisupervised learning has been an active research topic in machine learning and data mining. One main reason is that labeling examples is expensive and time-consuming, while there are large numbers of unlabeled examples available in many practical problems. So far, Laplacian regularization has been widely used in semisupervised learning. In this paper, we propose a new regularization method called tangent space intrinsic manifold regularization. It is intrinsic to data manifold and favors linear functions on the manifold. Fundamental elements involved in the formulation of the regularization are local tangent space representations, which are estimated by local principal component analysis, and the connections that relate adjacent tangent spaces. Simultaneously, we explore its application to semisupervised classification and propose two new learning algorithms called tangent space intrinsic manifold regularized support vector machines (TiSVMs) and tangent space intrinsic manifold regularized twin SVMs (TiTSVMs). They effectively integrate the tangent space intrinsic manifold regularization consideration. The optimization of TiSVMs can be solved by a standard quadratic programming, while the optimization of TiTSVMs can be solved by a pair of standard quadratic programmings. The experimental results of semisupervised classification problems show the effectiveness of the proposed semisupervised learning algorithms.
On almost regularity and π-normality of topological spaces
Saad Thabit, Sadeq Ali; Kamarulhaili, Hailiza
2012-05-01
π-Normality is a weaker version of normality. It was introduced by Kalantan in 2008. π-Normality lies between normality and almost normality (resp. quasi-normality). The importance of this topological property is that it behaves slightly different from normality and almost normality (quasi-normality). π-Normality is neither a productive nor a hereditary property in general. In this paper, some properties of almost regular spaces are presented. In particular, a few results on almost regular spaces are improved. Some relationships between almost regularity and π-normality are presented. π-Generalized closed sets are used to obtain a characterization and preservation theorems of π-normal spaces. Also, we investigate that an almost regular Lindelöf space (resp. with σ-locally finite base) is not necessarily π-normal by giving two counterexamples. An almost normality of the Rational Sequence topology is proved.
Maximal regularity of second order delay equations in Banach spaces
无
2010-01-01
We give necessary and sufficient conditions of Lp-maximal regularity(resp.B sp ,q-maximal regularity or F sp ,q-maximal regularity) for the second order delay equations:u″(t)=Au(t) + Gu’t + F u t + f(t), t ∈ [0, 2π] with periodic boundary conditions u(0)=u(2π), u′(0)=u′(2π), where A is a closed operator in a Banach space X,F and G are delay operators on Lp([-2π, 0];X)(resp.Bsp ,q([2π, 0];X) or Fsp,q([-2π, 0;X])).
Bi-Lipschitz Maps in Q-regular Loewner Spaces
Ke Ying CHEN; Ai Nong FANG
2008-01-01
By applying the theory of quasiconformal maps in measure metric spaces that was introduced by Heinonen–Koskela, we characterize bi-Lipschitz maps by modulus inequalities of rings and maximal, minimal derivatives in Q-regular Loewner spaces. Meanwhile the su?cient and necessary conditions for quasiconformal maps to become bi-Lipschitz maps are also obtained. These results generalize Rohde’s theorem in Rn and improve Balogh’s corresponding results in Carnot groups.
A quadratic rate of asymptotic regularity for CAT(0)-spaces
Leustean, Laurentiu
2005-01-01
In this paper we obtain a quadratic bound on the rate of asymptotic regularity for the Krasnoselski-Mann iterations of nonexpansive mappings in CAT(0)-spaces, whereas previous results guarantee only exponential bounds. The method we use is to extend to the more general setting of uniformly convex hyperbolic spaces a quantitative version of a strengthening of Groetsch's theorem obtained by Kohlenbach using methods from mathematical logic (so-called ``proof mining'').
REGULARITY OF POISSON EQUATION IN SOME LOGARITHMIC SPACE
Jia Huilian; Li Dongsheng; Wang Lihe
2007-01-01
In this note, the regularity of Poisson equation -△u = f with f lying in logarithmic function space Lp(LogL)a(Ω)(1＜p ＜∞, a ∈ R) is studied. The result of the note generalizes the W2,p estimate of Poisson equation in Lp(Ω).
On Lower Separation and Regularity Axioms in Fuzzy Topological Spaces
Amin Saif
2011-01-01
Full Text Available We use the concepts of the quasicoincident relation to introduce and investigate some lower separation axioms such as 0, 1, 1/2, and 2 as well as the regularity axioms 0 and 1. Further we study some of their properties and the relations among them in the general framework of fuzzy topological spaces.
Keller, Kai Johannes
2010-01-01
The present work contains a consistent formulation of the methods of dimensional regularization (DimReg) and minimal subtraction (MS) in Minkowski position space. The methods are implemented into the framework of perturbative Algebraic Quantum Field Theory (pAQFT). The developed methods are used to solve the Epstein-Glaser recursion for the construction of time-ordered products in all orders of causal perturbation theory. A solution is given in terms of a forest formula in the sense of Zimmer...
The effect of spacing regularity on visual crowding.
Saarela, T P; Westheimer, G; Herzog, M H
2010-08-18
Crowding limits peripheral visual discrimination and recognition: a target easily identified in isolation becomes impossible to recognize when surrounded by other stimuli, often called flankers. Most accounts of crowding predict less crowding when the target-flanker distance increases. On the other hand, the importance of perceptual organization and target-flanker coherence in crowding has recently received more attention. We investigated the effect of target-flanker spacing on crowding in multi-element stimulus arrays. We show that increasing the average distance between the target and the flankers does not always decrease the amount of crowding but can even sometimes increase it. We suggest that the regularity of inter-element spacing plays an important role in determining the strength of crowding: regular spacing leads to the perception of a single, coherent, texture-like stimulus, making judgments about the individual elements difficult.
Keller, Kai Johannes
2010-04-15
The present work contains a consistent formulation of the methods of dimensional regularization (DimReg) and minimal subtraction (MS) in Minkowski position space. The methods are implemented into the framework of perturbative Algebraic Quantum Field Theory (pAQFT). The developed methods are used to solve the Epstein-Glaser recursion for the construction of time-ordered products in all orders of causal perturbation theory. A solution is given in terms of a forest formula in the sense of Zimmermann. A relation to the alternative approach to renormalization theory using Hopf algebras is established. (orig.)
Restrictive metric regularity and generalized differential calculus in Banach spaces
Bingwu Wang
2004-10-01
Full Text Available We consider nonlinear mappings f:XÃ¢Â†Â’Y between Banach spaces and study the notion of restrictive metric regularity of f around some point xÃ‚Â¯, that is, metric regularity of f from X into the metric space E=f(X. Some sufficient as well as necessary and sufficient conditions for restrictive metric regularity are obtained, which particularly include an extension of the classical Lyusternik-Graves theorem in the case when f is strictly differentiable at xÃ‚Â¯ but its strict derivative Ã¢ÂˆÂ‡f(xÃ‚Â¯ is not surjective. We develop applications of the results obtained and some other techniques in variational analysis to generalized differential calculus involving normal cones to nonsmooth and nonconvex sets, coderivatives of set-valued mappings, as well as first-order and second-order subdifferentials of extended real-valued functions.
Regularity and predictability of human mobility in personal space.
Daniel Austin
Full Text Available Fundamental laws governing human mobility have many important applications such as forecasting and controlling epidemics or optimizing transportation systems. These mobility patterns, studied in the context of out of home activity during travel or social interactions with observations recorded from cell phone use or diffusion of money, suggest that in extra-personal space humans follow a high degree of temporal and spatial regularity - most often in the form of time-independent universal scaling laws. Here we show that mobility patterns of older individuals in their home also show a high degree of predictability and regularity, although in a different way than has been reported for out-of-home mobility. Studying a data set of almost 15 million observations from 19 adults spanning up to 5 years of unobtrusive longitudinal home activity monitoring, we find that in-home mobility is not well represented by a universal scaling law, but that significant structure (predictability and regularity is uncovered when explicitly accounting for contextual data in a model of in-home mobility. These results suggest that human mobility in personal space is highly stereotyped, and that monitoring discontinuities in routine room-level mobility patterns may provide an opportunity to predict individual human health and functional status or detect adverse events and trends.
Space Alignment Based on Regularized Inversion Precoding in Cognitive Transmission
R. Yao
2015-09-01
Full Text Available For a two-tier Multiple-Input Multiple-Output (MIMO cognitive network with common receiver, the precoding matrix has a compact relationship with the capacity performance in the unlicensed secondary system. To increase the capacity of secondary system, an improved precoder based on the idea of regularized inversion for secondary transmitter is proposed. An iterative space alignment algorithm is also presented to ensure the Quality of Service (QoS for primary system. The simulations reveal that, on the premise of achieving QoS for primary system, our proposed algorithm can get larger capacity in secondary system at low Signal-to-Noise Ratio (SNR, which proves the effectiveness of the algorithm.
Spherically Symmetric Space Time with Regular de Sitter Center
Dymnikova, Irina
We formulate the requirements which lead to the existence of a class of globally regular solutions of the minimally coupled GR equations asymptotically de Sitter at the center.REFID="S021827180300358XFN001"> The source term for this class, invariant under boosts in the radial direction, is classified as spherically symmetric vacuum with variable density and pressure Tμ ν vac associated with an r-dependent cosmological term Λ μ ν = 8π GTμ ν vac, whose asymptotic at the origin, dictated by the weak energy condition, is the Einstein cosmological term Λgμν, while asymptotic at infinity is de Sitter vacuum with λ < Λ or Minkowski vacuum. For this class of metrics the mass m defined by the standard ADM formula is related to both the de Sitter vacuum trapped at the origin and the breaking of space time symmetry. In the case of the flat asymptotic, space time symmetry changes smoothly from the de Sitter group at the center to the Lorentz group at infinity through radial boosts in between. Geometry is asymptotically de Sitter as r → 0 and asymptotically Schwarzschild at large r. In the range of masses m ≥ mcrit, the de Sitter Schwarzschild geometry describes a vacuum nonsingular black hole (ΛBH), and for m < mcrit it describes G-lump — a vacuum selfgravitating particle-like structure without horizons. In the case of de Sitter asymptotic at infinity, geometry is asymptotically de Sitter as r → 0 and asymptotically Schwarzschild de Sitter at large r. Λμν geometry describes, dependently on parameters m and q = √ {Λ /λ } and choice of coordinates, a vacuum nonsingular cosmological black hole, self-gravitating particle-like structure at the de Sitter background λgμν, and regular cosmological models with cosmological constant evolving smoothly from Λ to λ.
Hardy spaces on Ahlfors-regular quasi metric spaces a sharp theory
Alvarado, Ryan
2015-01-01
Systematically building an optimal theory, this monograph develops and explores several approaches to Hardy spaces in the setting of Ahlfors-regular quasi-metric spaces. The text is broadly divided into two main parts. The first part gives atomic, molecular, and grand maximal function characterizations of Hardy spaces and formulates sharp versions of basic analytical tools for quasi-metric spaces, such as a Lebesgue differentiation theorem with minimal demands on the underlying measure, a maximally smooth approximation to the identity and a Calderon-Zygmund decomposition for distributions. These results are of independent interest. The second part establishes very general criteria guaranteeing that a linear operator acts continuously from a Hardy space into a topological vector space, emphasizing the role of the action of the operator on atoms. Applications include the solvability of the Dirichlet problem for elliptic systems in the upper-half space with boundary data from Hardy spaces. The tools established ...
Regular implementation in the space of compactly supported functions
Napp Avelli, D.; Shankar, Shiva; Trentelman, H.L.
2008-01-01
This article extends results on regular implementability in [P. Rocha, Canonical controllers and regular implementation of nd behaviors, in: Proceedings of the 16th IFAC World Congress, 20051 and [H.L. Trentelman, D. Napp Avelli, On the regular implementability of nD systems, Systems Control Lett. 5
Arnfred, Sidse M.; Hansen, Lars Kai; Parnas, Josef
2008-01-01
). After initial exploration of the AvVVT and Induced collapsed files of all subjects using two-way factor analyses (Non-Negative Matrix Factorization), further data decomposition was performed in restricted windows of interest (WOI). Main effects of side of stimulation, onset or offset, regularity...
Ratanpal B S; Sharma Jaita
2016-03-01
The charged anisotropic star on paraboloidal space-time is reported by choosing a particular form of radial pressure and electric field intensity. The non-singular solution of Einstein–Maxwell system of equation has been derived and it is shown that the model satisfies all the physical plausibility conditions. It is observed that in the absence of electric field intensity, the model reducesto a particular case of uncharged Sharma and Ratanpal model. It is also observed that the parameter used in the electric field intensity directly affects mass of the star.
ON THE REGULARITY CRITERIA OF THE 3D NAVIER-STOKES EQUATIONS IN CRITICAL SPACES
Dong Boqing; Sadek Gala; Chen Zhimin
2011-01-01
Regularity criteria of Leray-Hopf weak solutions to the three-dimensional Navier-Stokes equations in some critical spaces such as Lorentz space, Morrey space and multiplier space are derived in terms of two partial derivatives, 1u1, 2u2, of velocity fields.
Embedding and Maximal Regular Differential Operators in Sobolev-Lions Spaces
Veli B. SHAKHMUROV
2006-01-01
This study focuses on vector-valued anisotropic Sobolev-Lions spaces associated with Banach spaces E0, E. Several conditions are found that ensure the continuity and compactness of embedding operators that are optimal regular in these spaces in terms of interpolations of spaces E0 and E. In particular, the most regular class of interpolation spaces Eα between E0, E depending on α and the order of space are found and the boundedness of differential operators Dα from this space to Eα -valued Lp,γ spaces is proved. These results are applied to partial differential-operator equationswith parameters to obtain conditions that guarantee the maximal Lp,γ regularity and R-positivity uniformly with respect to these parameters.
Elasticity imaging for regularly spaced structures utilizing WT matched filtering method
无
2002-01-01
Based on wavelet transform of time-scale domain, a new strain estimation method is presented to position the regular scatterers, calculate the local scatterer spacing and its change, and estimate the internal strain distribution of tissue mimicking phantom. Simulation and experiment results for uniform and nonuniform phantoms show the internal strain of regularly spaced structures can be estimated accurately using this method and the influence of global boundary condition on the estimated strain distribution can be eliminated by reconstructing the real elasticity distribution. This approach has the potentials to become a valuable tool for the regularly spaced structures.
A Banach Space Regularization Approach for Multifrequency Microwave Imaging
Claudio Estatico
2016-01-01
Full Text Available A method for microwave imaging of dielectric targets is proposed. It is based on a tomographic approach in which the field scattered by an unknown target (and collected in a proper observation domain is inverted by using an inexact-Newton method developed in Lp Banach spaces. In particular, the extension of the approach to multifrequency data processing is reported. The mathematical formulation of the new method is described and the results of numerical simulations are reported and discussed, analyzing the behavior of the multifrequency processing technique combined with the Banach spaces reconstruction method.
Regularization methods for a class of variational inequalities in banach spaces
Buong, Nguyen; Phuong, Nguyen Thi Hong
2012-11-01
In this paper, we introduce two regularization methods, based on the Browder-Tikhonov and iterative regularizations, for finding a solution of variational inequalities over the set of common fixed points of an infinite family of nonexpansive mappings on real reflexive and strictly convex Banach spaces with a uniformly Gateaux differentiate norm.
New properties of BK-spaces defined by using regular matrix of Fibonacci numbers
Ercan, Sinan; Bektaş, ćiǧdem A.
2016-06-01
In the present paper, we studied the new properties of BK-spaces which were defined using regular matrix of Fibonacci numbers in [1]. We computed alpha-, beta-, gamma- duals of these spaces and obtained Schauder basis. We also derived some topological properties of these spaces.
Visualization of Sound Waves Using Regularly Spaced Soap Films
Elias, F.; Hutzler, S.; Ferreira, M. S.
2007-01-01
We describe a novel demonstration experiment for the visualization and measurement of standing sound waves in a tube. The tube is filled with equally spaced soap films whose thickness varies in response to the amplitude of the sound wave. The thickness variations are made visible based on optical interference. The distance between two antinodes is…
Effective regularity in modulation on gastric motility induced by different acupoint stimulation
Yu-Qing Li; Bing Zhu; Pei-Jing Rong; Hui Ben; Yan-Hua Li
2006-01-01
AIM: To investigate whether manual acupuncture at representative acupoints in different parts of the body can modulate responses of gastric motility in rats and regular effects in different acupoint stimulation.METHODS: The gastric motor activity of rats was recorded by the intrapyloric balloon. The changes of gastric motility induced by the stimulation were compared with the background activity in intragastric pressure and/or waves of gastric contraction recorded before any stimulation. Morphological study was also conducted by observing the Evans dye extravasation in the skin after mustard oil injection into the intragastric mucous membrane to certify cutaneous innervations of blue dots related to gastric segmental innervations.RESULTS: In all six rats that received mustard oil injections into intragastric mucosa, small blue dots appeared in the skin over the whole abdomen, but mainly in peri-midline upper- and middle- abdomen and middle-back, a few in thigh and groin. It may speculate that cutaneous innervations of blue dots have the same distribution as gastric segmental innervations. Acustimulation in acupoints of head-neck, four limbs, upper chest-dorsum and lower-dorsum induced markedly augmentation of gastric motility (acupoints on headneck such as St-2:n = 16, 105.19 ± 1.36 vs112.25 ± 2.02 and St-3:n = 14, 101.5 ± 1.75 vs109.36 ± 1.8;acupoints on limbs such as Sp-6:n = 19, 100.74 ± 1.54 vs110.26 ± 3.88; St-32:n = 17, 103.59 ± 1.64 vs 108.24 ± 2.41; St-36:n = 16, 104.81 ± 1.72 vs 110.81 ± 2.74 and Li-11: n = 17, 106.47 ± 2.61 vs 114.77 ± 3.77, P ＜ 0.05-0.001). Vigorous inhibitory regulations of gastric motility induced by acu-stimulation applied in acupoints on whole abdomen and middle-dorsum were significantly different as compared with the controls before acu-stimulation (abdomen acupoints such as Cv-12:n = 11, 109.36 ± 2.09 vs 101 ± 2.21; Cv-6:n = 18, 104.39 ± 1.42 vs 91.83 ± 3.22 and St-21: n= 12, 107 ± 2.97 vs 98.58 ± 2
Dütsch, Michael; Fredenhagen, Klaus; Keller, Kai J.; Rejzner, Katarzyna Anna
2013-01-01
We reformulate dimensional regularization as a regularization method in position space and show that it can be used to give a closed expression for the renormalized time-ordered products as solutions to the induction scheme of Epstein-Glaser. For scalar fields the resulting renormalization method is always applicable, we compute several examples. We also analyze the Hopf algebraic aspects of the combinatorics. Our starting point is the Main Theorem of Renormalization of Stora and Popineau and...
Heuvel, S.G. van den; Looze, M.P. de; Hildebrandt, V.H.; Thé, K.H.
2003-01-01
Objectives. This study evaluated the effects on work-related neck and upper-limb disorders among computer workers stimulated (by a software program) to take regular breaks and perform physical exercises. Possible effects on sick leave and productivity were studied as well. Methods. A randomized cont
Total variation regularization in measurement and image space for PET reconstruction
Burger, M
2014-09-18
© 2014 IOP Publishing Ltd. The aim of this paper is to test and analyse a novel technique for image reconstruction in positron emission tomography, which is based on (total variation) regularization on both the image space and the projection space. We formulate our variational problem considering both total variation penalty terms on the image and on an idealized sinogram to be reconstructed from a given Poisson distributed noisy sinogram. We prove existence, uniqueness and stability results for the proposed model and provide some analytical insight into the structures favoured by joint regularization. For the numerical solution of the corresponding discretized problem we employ the split Bregman algorithm and extensively test the approach in comparison to standard total variation regularization on the image. The numerical results show that an additional penalty on the sinogram performs better on reconstructing images with thin structures.
On Landweber-Kaczmarz methods for regularizing systems of ill-posed equations in Banach spaces
Leitão, A.; Marques Alves, M.
2012-10-01
In this paper, iterative regularization methods of Landweber-Kaczmarz type are considered for solving systems of ill-posed equations modeled (finitely many) by operators acting between Banach spaces. Using assumptions of uniform convexity and smoothness on the parameter space, we are able to prove a monotony result for the proposed method, as well as to establish convergence (for exact data) and stability results (in the noisy data case).
On rarely generalized regular fuzzy continuous functions in fuzzy topological spaces
Appachi Vadivel
2016-11-01
Full Text Available In this paper, we introduce the concept of rarely generalized regular fuzzy continuous functions in the sense of A.P. Sostak's and Ramadan is introduced. Some interesting properties and characterizations of them are investigated. Also, some applications to fuzzy compact spaces are established.
ON GENERALIZED b-REGULAR CLOSED SETS IN SUPRA TOPOLOGICAL SPACES
M.Trinita Pricilla*, I.Arockiarani
2012-01-01
Full Text Available In this paper, we introduce new class of sets called supra generalized b regular closed sets. We obtain the basic properties and their relationships with other classes of sets in supra topological spaces. Mathematics Subject, Classification: 54A10, 54A20
Dimensional regularization in position space and a Forest Formula for Epstein-Glaser renormalization
Dütsch, Michael; Fredenhagen, Klaus; Keller, Kai Johannes; Rejzner, Katarzyna
2014-12-01
We reformulate dimensional regularization as a regularization method in position space and show that it can be used to give a closed expression for the renormalized time-ordered products as solutions to the induction scheme of Epstein-Glaser. This closed expression, which we call the Epstein-Glaser Forest Formula, is analogous to Zimmermann's Forest Formula for BPH renormalization. For scalar fields, the resulting renormalization method is always applicable, we compute several examples. We also analyze the Hopf algebraic aspects of the combinatorics. Our starting point is the Main Theorem of Renormalization of Stora and Popineau and the arising renormalization group as originally defined by Stückelberg and Petermann.
Two regularization methods for solving a Riesz-Feller space-fractional backward diffusion problem
Zheng, G. H.; Wei, T.
2010-11-01
In this paper, a backward diffusion problem for a space-fractional diffusion equation (SFDE) in a strip is investigated. Such a problem is obtained from the classical diffusion equation in which the second-order space derivative is replaced with a Riesz-Feller derivative of order β in (0, 2]. We show that such a problem is severely ill-posed and further propose a new regularization method and apply a spectral regularization method to solve it based on the solution given by the Fourier method. Convergence estimates are presented under a priori bound assumptions for the exact solution. Finally, numerical examples are given to show that the proposed numerical methods are effective.
Salt-body Inversion with Minimum Gradient Support and Sobolev Space Norm Regularizations
Kazei, V.V.
2017-05-26
Full-waveform inversion (FWI) is a technique which solves the ill-posed seismic inversion problem of fitting our model data to the measured ones from the field. FWI is capable of providing high-resolution estimates of the model, and of handling wave propagation of arbitrary complexity (visco-elastic, anisotropic); yet, it often fails to retrieve high-contrast geological structures, such as salt. One of the reasons for the FWI failure is that the updates at earlier iterations are too smooth to capture the sharp edges of the salt boundary. We compare several regularization approaches, which promote sharpness of the edges. Minimum gradient support (MGS) regularization focuses the inversion on blocky models, even more than the total variation (TV) does. However, both approaches try to invert undesirable high wavenumbers in the model too early for a model of complex structure. Therefore, we apply the Sobolev space norm as a regularizing term in order to maintain a balance between sharp and smooth updates in FWI. We demonstrate the application of these regularizations on a Marmousi model, enriched by a chunk of salt. The model turns out to be too complex in some parts to retrieve its full velocity distribution, yet the salt shape and contrast are retrieved.
Space-Dependent Sobolev Gradients as a Regularization for Inverse Radiative Transfer Problems
Y. Favennec
2016-01-01
Full Text Available Diffuse optical tomography problems rely on the solution of an optimization problem for which the dimension of the parameter space is usually large. Thus, gradient-type optimizers are likely to be used, such as the Broyden-Fletcher-Goldfarb-Shanno (BFGS algorithm, along with the adjoint-state method to compute the cost function gradient. Usually, the L2-inner product is chosen within the extraction procedure (i.e., in the definition of the relationship between the cost function gradient and the directional derivative of the cost function while alternative inner products that act as regularization can be used. This paper presents some results based on space-dependent Sobolev inner products and shows that this method acts as an efficient low-pass filter on the cost function gradient. Numerical results indicate that the use of Sobolev gradients can be particularly attractive in the context of inverse problems, particularly because of the simplicity of this regularization, since a single additional diffusion equation is to be solved, and also because the quality of the solution is smoothly varying with respect to the regularization parameter.
Critical phenomena of regular black holes in anti-de Sitter space-time
Fan, Zhong-Ying
2016-01-01
In General Relativity coupled to a non-linear electromagnetic field, together with a negative cosmological constant, we obtain the general static spherical symmetric black hole solution with magnetic charges, which is asymptotic to anti-de Sitter (AdS) space-times. In particular, for a degenerate case the solution becomes a Hayward-AdS black hole, which is regular everywhere in the full space-time. The existence of such a regular black hole solution preserves the weak energy condition while the strong energy condition is violated. We then derive the first law and the Smarr formula of the black hole solution. We further discuss its thermodynamic properties and study the critical phenomena in the extended phase space where the cosmological constant is treated as a thermodynamic variable as well as the parameter associated with the non-linear electrodynamics. We obtain many interesting results such as: the Maxwell's equal area law in the $P-V$ (or $S-T$) diagram is violated and consequently the critical point $(...
Horoball packings to the totally asymptotic regular simplex in the hyperbolic $n$-space
Szirmai, Jenő
2011-01-01
In \\cite{Sz11} we have generalized the notion of the simplicial density function for horoballs in the extended hyperbolic space $\\bar{\\mathbf{H}}^n, ~(n \\ge 2)$, where we have allowed {\\it congruent horoballs in different types} centered at the various vertices of a totally asymptotic tetrahedron. By this new aspect, in this paper we study the locally densest horoball packing arrangements and their densities with respect to totally asymptotic regular tetrahedra in hyperbolic $n$-space $\\bar{\\mathbf{H}}^n$ extended with its absolute figure, where the ideal centers of horoballs give rise to vertices of a totally asymptotic regular tetrahedron. We will prove that, in this sense, {\\it the well known B\\"or\\"oczky density upper bound for "congruent horoball" packings of $\\bar{\\mathbf{H}}^n$ does not remain valid for $n\\ge4$,} but these locally optimal ball arrangements do not have extensions to the whole $n$-dimensional hyperbolic space. Moreover, we determine an explicit formula for the density of the above locall...
On the regularity of mild solutions to complete higher order differential equations on Banach spaces
Nezam Iraniparast
2015-09-01
Full Text Available For the complete higher order differential equation u(n(t=Σk=0n-1Aku(k(t+f(t, t∈ R (* on a Banach space E, we give a new definition of mild solutions of (*. We then characterize the regular admissibility of a translation invariant subspace al M of BUC(R, E with respect to (* in terms of solvability of the operator equation Σj=0n-1AjXal Dj-Xal Dn = C. As application, almost periodicity of mild solutions of (* is proved.
Results on n-tupled fixed points in complete asymptotically regular metric spaces
Anupam Sharma
2014-10-01
Full Text Available The notion of n-tupled fixed point is introduced by Imdad, Soliman, Choudhury and Das, Jour. of Operators, Vol. 2013, Article ID 532867. In this manuscript, we prove some n-tupled fixed point theorems (for even n for mappings having mixed monotone property in partially ordered complete asymptotically regular metric spaces. Our main theorem improves the corresponding results of Imdad, Sharma and Rao (M. Imdad, A. Sharma, K.P.R. Rao, Generalized n-tupled fixed point theorems for nonlinear contractions, preprint.
Appearance of implicative regularities in Boolean criterion space and pattern recognition
Zakrevskii, A.D.
1982-01-01
A new approach to the solution of problems in recognition theory is noted within the framework of the more general problem of the appearance of regularities in the data flow, and of the problem of converting the latter into knowledge, is some adequate model of the class of objects under investigation that operationally permit finding the solution of diverse problems of pattern recognition, classification, empirical prediction, filling in the blanks in experimental tables, etc. This approach is developed in application to the case of binary criteria, which permits efficient utilization of the apparatus of Boolean function theory, but allows extension also of the case of multi-valued criteria. A method is proposed for the determination, by a training sample, of the general properties of a single class of real objects representable by appropriate points of the Boolean space m of all criteria. The method relies on a unique a priori hypothesis about the preference of regularities connecting minimal groups of criteria. The expediency of the appearance of sufficiently strong regularities of the type elementary exclusions that yield implicative relations between criteria and the construction of differentiated prediction procedures on their basis, which permit extrapolation of partially assigned properties of objects not in the training sample with a foundation will follow logically from this hypothesis. 12 references.
Tóth, L Fejes; Ulam, S; Stark, M
1964-01-01
Regular Figures concerns the systematology and genetics of regular figures. The first part of the book deals with the classical theory of the regular figures. This topic includes description of plane ornaments, spherical arrangements, hyperbolic tessellations, polyhedral, and regular polytopes. The problem of geometry of the sphere and the two-dimensional hyperbolic space are considered. Classical theory is explained as describing all possible symmetrical groupings in different spaces of constant curvature. The second part deals with the genetics of the regular figures and the inequalities fo
Batikian, T B; Akopian, G V; Lazian, M P; Torgomian, T R; Kazarian, R A; Amirkhanian, E S; Tadevosian, Iu V
2011-01-01
Regularities of biologically active lipid metabolites formation in dynamics (5, 10, 30, 60 s) by phorbol 12-miristate 13-acetate stimulation in [14C]palmitic acid have been investigated in normal and leukemia peripheral blood lymphocytes prelabeled with [14C]palmitate. In normal cells there was two-phase formation of 1,2-diacylglycerol (5, 30 s), lysophosphatidylcholine (10, 60 s), as well as free palmitic acid at 10 s of stimulation. Under the identical experimental conditions there was inhibition of investigated lipid release processes at early (5 and 10 s) stages of stimulation of leukemic lymphocytes. At later (30, 60 s) terms of these lymphocytes the activation, basically, similar to norm changes in the formation of palmitic acid-containing metabolites except free palmitic acid (the level of which raised only at 60 second of the post-stimulation) was found. Various protein kinases C are involved in the regulation of investigated lipid levels at certain stages of signal transduction both in norm, and in blast cells. Short-term (5, 10 s) activations of healthy donors lymphocytes are coupled to functioning of Ca2+-independent isoforms of protein kinase C. The inhibition of this protein kinase C in leukemic cells leads to normalization of the investigated lipid release. The data obtained suggests disorders of early membrane-bound reactions in agonist - and a protein kinase C-mediated processes of formation palmitic acid-containing lipid metabolites in the leukemic cells in comparison with the norm.
Cappa, G.; Ferrari, S.
2016-12-01
Let X be a separable Banach space endowed with a non-degenerate centered Gaussian measure μ. The associated Cameron-Martin space is denoted by H. Let ν =e-U μ, where U : X → R is a sufficiently regular convex and continuous function. In this paper we are interested in the W 2 , 2 regularity of the weak solutions of elliptic equations of the type
A Riesz representation theory for completely regular Hausdorff spaces and its applications
Nowak Marian
2016-01-01
Full Text Available Let X be a completely regular Hausdorff space, E and F be Banach spaces. Let Cb(X, E be the space of all E-valued bounded, continuous functions on X, equipped with the strict topology β. We develop the Riemman-Stieltjes-type Integral representation theory of (β, || · ||F -continuous operators T : Cb(X, E → F with respect to the representing Borel operator measures. For X being a k-space, we characterize strongly bounded (β, || · ||F-continuous operators T : Cb(X, E → F. As an application, we study (β, || · ||F-continuous weakly compact and unconditionally converging operators T : Cb(X, E → F. In particular, we establish the relationship between these operators and the corresponding Borel operator measures given by the Riesz representation theorem. We obtain that if X is a k-spaceand E is reflexive, then (Cb(X, E, β has the V property of Pełczynski.
Critical phenomena of regular black holes in anti-de Sitter space-time
Fan, Zhong-Ying [Peking University, Center for High Energy Physics, Beijing (China)
2017-04-15
In General Relativity, addressing coupling to a non-linear electromagnetic field, together with a negative cosmological constant, we obtain the general static spherical symmetric black hole solution with magnetic charges, which is asymptotic to anti-de Sitter (AdS) space-times. In particular, for a degenerate case the solution becomes a Hayward-AdS black hole, which is regular everywhere in the full space-time. The existence of such a regular black hole solution preserves the weak energy condition, while the strong energy condition is violated. We then derive the first law and the Smarr formula of the black hole solution. We further discuss its thermodynamic properties and study the critical phenomena in the extended phase space where the cosmological constant is treated as a thermodynamic variable as well as the parameter associated with the non-linear electrodynamics. We obtain many interesting results such as: the Maxwell equal area law in the P-V (or S-T) diagram is violated and consequently the critical point (T{sub *},P{sub *}) of the first order small-large black hole transition does not coincide with the inflection point (T{sub c},P{sub c}) of the isotherms; the Clapeyron equation describing the coexistence curve of the Van der Waals (vdW) fluid is no longer valid; the heat capacity at constant pressure is finite at the critical point; the various exponents near the critical point are also different from those of the vdW fluid. (orig.)
Huber, Florian; Strehle, Dan; Schnauß, Jörg; Käs, Josef
2015-04-01
Biopolymer networks contribute mechanical integrity as well as functional organization to living cells. One of their major constituents, the protein actin, is present in a large variety of different network architectures, ranging from extensive networks to densely packed bundles. The shape of the network is directly linked to its mechanical properties and essential physiological functions. However, a profound understanding of architecture-determining mechanisms and their physical constraints remains elusive. We use experimental bottom-up systems to study the formation of confined actin networks by entropic forces. Experiments based on molecular crowding as well as counterion condensation reveal a generic tendency of homogeneous filament solutions to aggregate into regular actin bundle networks connected by aster-like centers. The network architecture is found to critically rely on network formation history. Starting from identical biochemical compositions, we observe drastic changes in network architecture as a consequence of initially biased filament orientation or mixing-induced perturbations. Our experiments suggest that the tendency to form regularly spaced bundle networks is a rather general feature of isotropic, homogeneous filament solutions subject to uniform attractive interactions. Due to the fundamental nature of the considered interactions, we expect that the investigated type of network formation further implies severe physical constraints for cytoskeleton self-organization on the more complex level of living cells.
Schöpfer, F.; Schuster, T.; Louis, A. K.
2008-10-01
The split feasibility problem (SFP) consists of finding a common point in the intersection of finitely many convex sets, where some of the sets arise by imposing convex constraints in the range of linear operators. We are concerned with its solution in Banach spaces. To this end we generalize the CQ algorithm of Byrne with Bregman and metric projections to obtain an iterative solution method. In case the sets projected onto are contaminated with noise we show that a discrepancy principle renders this algorithm a regularization method. We measure the distance between convex sets by local versions of the Hausdorff distance, which in contrast to the standard Hausdorff distance allow us to measure the distance between unbounded sets. Hereby we prove a uniform continuity result for both kind of projections. The performance of the algorithm is demonstrated with some numerical experiments.
Fast ℓ1-regularized space-time adaptive processing using alternating direction method of multipliers
Qin, Lilong; Wu, Manqing; Wang, Xuan; Dong, Zhen
2017-04-01
Motivated by the sparsity of filter coefficients in full-dimension space-time adaptive processing (STAP) algorithms, this paper proposes a fast ℓ1-regularized STAP algorithm based on the alternating direction method of multipliers to accelerate the convergence and reduce the calculations. The proposed algorithm uses a splitting variable to obtain an equivalent optimization formulation, which is addressed with an augmented Lagrangian method. Using the alternating recursive algorithm, the method can rapidly result in a low minimum mean-square error without a large number of calculations. Through theoretical analysis and experimental verification, we demonstrate that the proposed algorithm provides a better output signal-to-clutter-noise ratio performance than other algorithms.
Playful Interactions Stimulating Physical Activity in Public Spaces
Sturm, Janienke; Bekker, Tilde; Vanden Abeele, Vero
that stimulate physical activity for various user groups and in various use contexts, and present some general findings on the basis of these cases. New technologies such as mobile networks and social media provide new opportunities for creating location-independent solutions that support groups of people......In this position paper we describe our vision on designing playful interactions to persuade people to be physically active in public spaces. Social embeddedness and playful interaction are the core elements of this vision. We illustrate how our design vision is incorporated into innovative concepts...... to motivate each other to be physically active by creating challenges for each other. Designing playful solutions for public spaces asks for low-threshold solutions that support easy stepping in and stepping out solutions....
Tuyen Truong
2011-01-01
Full Text Available Abstract We study the strong convergence of a regularization proximal point algorithm for finding a common fixed point of a finite family of nonexpansive mappings in a uniformly convex and uniformly smooth Banach space. 2010 Mathematics Subject Classification: 47H09; 47J25; 47J30.
VANENTER, ACD; FERNANDEZ, R; SOKAL, AD
We reconsider the conceptual foundations of the renormalization-group (RG) formalism, and prove some rigorous theorems on the regularity properties and possible pathologies of the RG map. Our main results apply to local (in position space) RG maps acting on systems of bounded spins (compact
Representations of Co-regular Subsets on Euclidean Spaces%欧氏空间上Co-regular集的表示式
邱玉文; 王莉萍; 赵希顺
2007-01-01
For the computability of co-regular subsets in metric spaces, the properties of the co-regular subsets and several reasonable representations on co-regular sets have been suggested in this paper. As last, the 'weaker or stronger' relations of these representations have been revealed.
Yan-fei Wang; Qing-hua Ma
2006-01-01
The adaptive regularization method is first proposed by Ryzhikov et al. in [6] for the deconvolution in elimination of multiples which appear frequently in geoscience and remote sensing. They have done experiments to show that this method is very effective. This method is better than the Tikhonov regularization in the sense that it is adaptive, i.e., it automatically eliminates the small eigenvalues of the operator when the operator is near singular. In this paper, we give theoretical analysis about the adaptive regularization. We introduce an a priori strategy and an a posteriori strategy for choosing the regularization parameter, and prove regularities of the adaptive regularization for both strategies. For the former, we show that the order of the convergence rate can approach 2Ov(‖n‖ 4v/4v+1 ) for some 0 ＜ v ＜ 1, while for the latter, the order of the convergence rate can be at most O(‖n‖ 2v/2v+1) for some 0 ＜ v ＜ 1.
无
2002-01-01
A modified Monte-Carlo(MC) method to simulate the regular growth of binary eutectic alloys is presented. It is found that the growth rate has a linear dependence on the chemical potential difference between the solid and liquid; the relation between the lamellar spacing λ and growth rate R accords well with the prediction of Jackson-Hunt(JH)theory unless the growth rate is very Iow.
Regularities in the frequency spacings of Delta Scuti stars and the s-f Diagram
Breger, M.; Lenz, P.; Pamyatnykh, A. A.
2008-12-01
Statistical analyses of several δ Scuti stars (FG Vir, 44 Tau, BL Cam and others) show that the photometrically observed frequencies cluster around the frequencies of the radial modes over many radial orders. The observed regularities can be partly explained by modes trapped in the stellar envelope. This mode selection mechanism was already proposed by Dziembowski & Krolikowska (1990) and was shown to be efficient for ℓ = 1 modes. New pulsation model calculations confirm the observed regularities. We present the s-f diagram, which compares the average separation of the radial frequen- cies (s) with the frequency of the lowest unstable radial mode (f ). The diagram provides an estimate for the log g value of the observed star, if we assume that the centers of the observed frequency clusters correspond to the radial mode frequencies. This assumption is confirmed by examples of well-studied δ Scuti variables in which radial modes were definitely identified.
Paparó, M; Hareter, M; Guzik, J A
2016-01-01
A sequence search method was developed to search regular frequency spacing in delta Scuti stars by visual inspection and algorithmic search. We searched for sequences of quasi-equally spaced frequencies, containing at least four members per sequence, in 90 delta Scuti stars observed by CoRoT. We found an unexpectedly large number of independent series of regular frequency spacing in 77 delta Scuti stars (from 1 to 8 sequences) in the non-asymptotic regime. We introduce the sequence search method presenting the sequences and echelle diagram of CoRoT 102675756 and the structure of the algorithmic search. Four sequences (echelle ridges) were found in the 5-21 d^{-1} region, where the pairs of the sequences are shifted (between 0.5-0.59 d^{-1}) by twice the value of the estimated rotational splitting frequency (0.269 d^{-1}). The general conclusions for the whole sample are also presented in this paper. The statistics of the spacings derived by the sequence search method, by FT and that of the shifts are also com...
Paparó, M.; Benkő, J. M.; Hareter, M.; Guzik, J. A.
2016-05-01
A sequence search method was developed to search the regular frequency spacing in δ Scuti stars through visual inspection and an algorithmic search. We searched for sequences of quasi-equally spaced frequencies, containing at least four members per sequence, in 90 δ Scuti stars observed by CoRoT. We found an unexpectedly large number of independent series of regular frequency spacing in 77 δ Scuti stars (from one to eight sequences) in the non-asymptotic regime. We introduce the sequence search method presenting the sequences and echelle diagram of CoRoT 102675756 and the structure of the algorithmic search. Four sequences (echelle ridges) were found in the 5-21 d-1 region where the pairs of the sequences are shifted (between 0.5 and 0.59 d-1) by twice the value of the estimated rotational splitting frequency (0.269 d-1). The general conclusions for the whole sample are also presented in this paper. The statistics of the spacings derived by the sequence search method, by FT (Fourier transform of the frequencies), and the statistics of the shifts are also compared. In many stars more than one almost equally valid spacing appeared. The model frequencies of FG Vir and their rotationally split components were used to formulate the possible explanation that one spacing is the large separation while the other is the sum of the large separation and the rotational frequency. In CoRoT 102675756, the two spacings (2.249 and 1.977 d-1) are in better agreement with the sum of a possible 1.710 d-1 large separation and two or one times, respectively, the value of the rotational frequency.
Zou, Yong; Donner, Reik V; Thiel, Marco; Kurths, Jürgen
2016-02-01
Recurrence in the phase space of complex systems is a well-studied phenomenon, which has provided deep insights into the nonlinear dynamics of such systems. For dissipative systems, characteristics based on recurrence plots have recently attracted much interest for discriminating qualitatively different types of dynamics in terms of measures of complexity, dynamical invariants, or even structural characteristics of the underlying attractor's geometry in phase space. Here, we demonstrate that the latter approach also provides a corresponding distinction between different co-existing dynamical regimes of the standard map, a paradigmatic example of a low-dimensional conservative system. Specifically, we show that the recently developed approach of recurrence network analysis provides potentially useful geometric characteristics distinguishing between regular and chaotic orbits. We find that chaotic orbits in an intermittent laminar phase (commonly referred to as sticky orbits) have a distinct geometric structure possibly differing in a subtle way from those of regular orbits, which is highlighted by different recurrence network properties obtained from relatively short time series. Thus, this approach can help discriminating regular orbits from laminar phases of chaotic ones, which presents a persistent challenge to many existing chaos detection techniques.
Zou, Yong; Donner, Reik V.; Thiel, Marco; Kurths, Jürgen
2016-02-01
Recurrence in the phase space of complex systems is a well-studied phenomenon, which has provided deep insights into the nonlinear dynamics of such systems. For dissipative systems, characteristics based on recurrence plots have recently attracted much interest for discriminating qualitatively different types of dynamics in terms of measures of complexity, dynamical invariants, or even structural characteristics of the underlying attractor's geometry in phase space. Here, we demonstrate that the latter approach also provides a corresponding distinction between different co-existing dynamical regimes of the standard map, a paradigmatic example of a low-dimensional conservative system. Specifically, we show that the recently developed approach of recurrence network analysis provides potentially useful geometric characteristics distinguishing between regular and chaotic orbits. We find that chaotic orbits in an intermittent laminar phase (commonly referred to as sticky orbits) have a distinct geometric structure possibly differing in a subtle way from those of regular orbits, which is highlighted by different recurrence network properties obtained from relatively short time series. Thus, this approach can help discriminating regular orbits from laminar phases of chaotic ones, which presents a persistent challenge to many existing chaos detection techniques.
Ito's formula in UMD Banach spaces and regularity of solution of the Zakai equation
Brzezniak, Z.; Van Neerven, J.M.A.M.; Veraar, M.C.; Weis, L.
2008-01-01
Using the theory of stochastic integration for processes with values in a UMD Banach space developed recently by the authors, an Itô formula is proved which is applied to prove the existence of strong solutions for a class of stochastic evolution equations in UMD Banach spaces. The abstract results
Ito's formula in UMD Banach spaces and regularity of solution of the Zakai equation
Brzezniak, Z.; Van Neerven, J.M.A.M.; Veraar, M.C.; Weis, L.
2008-01-01
Using the theory of stochastic integration for processes with values in a UMD Banach space developed recently by the authors, an Itô formula is proved which is applied to prove the existence of strong solutions for a class of stochastic evolution equations in UMD Banach spaces. The abstract
On the space and time evolution of regular or irregular human heart or brain signals
Tuncay, Caglar
2011-01-01
A coupled map is suggested to investigate various spatial or temporal designs in biology: Several cells (or tissues) in an organ are considered as connected to each other in terms of some molecular diffusions or electrical potential differences and so on. The biological systems (groups of cells) start from various initial conditions for spatial designs (or initial signals for temporal designs) and they evolve in time in terms of the mentioned interactions (connections) besides some individual feedings. The basic aim of the present contribution is to mimic various empirical data for the heart (in normal, quasi-stable, unstable and post operative physiological conditions) or brain (regular or irregular; for epilepsy) signals. The mentioned empirical data are borrowed from various literatures which are cited. The suggested model (to be used besides or instead of the artificial network models) involves simple mathematics and the related software is easy. The results may be considered as in good agreement with the...
Space-time fractional diffusion equation using a derivative with nonsingular and regular kernel
Gómez-Aguilar, J. F.
2017-01-01
In this paper, using the fractional operators with Mittag-Leffler kernel in Caputo and Riemann-Liouville sense the space-time fractional diffusion equation is modified, the fractional equation will be examined separately; with fractional spatial derivative and fractional temporal derivative. For the study cases, the order considered is 0 < β , γ ≤ 1 respectively. In this alternative representation we introduce the appropriate fractional dimensional parameters which characterize consistently the existence of the fractional space-time derivatives into the fractional diffusion equation, these parameters related to equation results in a fractal space-time geometry provide a new family of solutions for the diffusive processes. The proposed mathematical representation can be useful to understand electrochemical phenomena, propagation of energy in dissipative systems, viscoelastic materials, material heterogeneities and media with different scales.
BV-capacities on Wiener Spaces and Regularity of the Maximum of the Wiener Process
Trevisan, Dario
2012-01-01
We define a capacity C on abstract Wiener spaces and prove that, for any u with bounded variation, the total variation measure |Du| is absolutely continuous with respect to C: this enables us to extend the usual rules of calculus in many cases dealing with BV functions. As an application, we show that, on the classical Wiener space, the random variable sup_{0\\leqt\\leqT} W_t admits a measure as second derivative, whose total variation measure is singular w.r.t. the Wiener measure.
Peng, Xu; Brügger, Kim; Shen, Biao
2003-01-01
Short regularly spaced repeats (SRSRs) occur in multiple large clusters in archaeal chromosomes and as smaller clusters in some archaeal conjugative plasmids and bacterial chromosomes. The sequence, size, and spacing of the repeats are generally constant within a cluster but vary between clusters...... that are identical in sequence to one of the repeat variants in the S. solfataricus chromosome. Repeats from the pNOB8 cluster were amplified and tested for protein binding with cell extracts from S. solfataricus. A 17.5-kDa SRSR-binding protein was purified from the cell extracts and sequenced. The protein is N...... terminally modified and corresponds to SSO454, an open reading frame of previously unassigned function. It binds specifically to DNA fragments carrying double and single repeat sequences, binding on one side of the repeat structure, and producing an opening of the opposite side of the DNA structure. It also...
Chiral Anomaly in a $\\gamma_5$-friendly momentum space regularization framework
Scarpelli, A P B; Hiller, B; Nemes, M C
2001-01-01
This is the second in a series of two contributions in which we set out to establish a novel momentum space framework to treat field theoretical infinities in perturbative calculations when parity-violating objects occur. Since no analytic continuation on the space-time dimension is effected, this framework is particularly useful to treat dimension-specific theories. Moreover (finite) arbitrary local terms stemming from the underlying infinities of the model are properly parametrized. We (re)analyse the undeterminacy of the radiatively generated CPT violating Chern-Simons term within an extended version of $QED_4$ and calculate the Adler-Bardeen-Jackiw triangle anomaly to show that our framework is consistent and general to handle the subtleties involved when a radiative corretion is finite.
Hoson, Takayuki; Soga, Kouichi; Mori, Ryuji; Saiki, Mizue; Nakamura, Yukiko; Wakabayashi, Kazuyuki; Kamisaka, Seiichiro
2002-09-01
We analyzed the growth rate and the cell wall properties of coleoptiles of rice seedlings grown at 23.6 degrees C for 68.5, 91.5 and 136 h during the Space Shuttle STS-95 mission. In space, elongation growth of coleoptiles was stimulated and the cell wall extensibility increased. Also, the levels of the cell wall polysaccharides per unit length of coleoptiles and the relative content of the high molecular mass matrix polysaccharides decreased in space. These differences in the cell wall polysaccharides could be involved in increasing the cell wall extensibility, leading to growth stimulation of rice coleoptiles in space.
Regularity properties and pathologies of position-space renormalization-group transformations
van Enter, Aernout C. D.; Fernández, Roberto; Sokal, Alan D.
1991-05-01
We consider the conceptual foundations of the renormalization-group (RG) formalism. We show that the RG map, defined on a suitable space of interactions, is always single-valued and Lipschitz continuous on its domain of definition. This rules out a recently proposed scenario for the RG description of first-order phase transitions. On the other hand, we prove in several cases that near a first-order phase transition the renormalized measure is not a Gibbs measure for any reasonable interaction. It follows that the conventional RG description of first-order transitions is not universally valid.
Playful Interactions Stimulating Physical Activity in Public Spaces
Sturm, Janienke; Bekker, Tilde; Vanden Abeele, Vero;
In this position paper we describe our vision on designing playful interactions to persuade people to be physically active in public spaces. Social embeddedness and playful interaction are the core elements of this vision. We illustrate how our design vision is incorporated into innovative concepts...... to motivate each other to be physically active by creating challenges for each other. Designing playful solutions for public spaces asks for low-threshold solutions that support easy stepping in and stepping out solutions....
Luciana Cátia Loose Pereira
2012-03-01
Full Text Available Inclusive education in Brazil has been widely discussed in all areas of the educational. The inclusion of pupils with special educational needs (SEN in mainstream schools is increasingly frequent, though still many aspects need to be rethought. This work aimed at checking how the subjects with SEN in Early Stimulation age, from zero to three years and 11 months are included into the regular classroom environment, at Nursery Schools, of an average municipality - Vale dos Sinos. This work involved a cross-sectional survey of quantitative and descriptive statistics. The data collection was carried out directly from a structured questionnaire with open and closed questions, directed to all principals of the thirteen Nursery Schools in the referred municipality. From the thirteen schools of the municipality only one did not take part of the research since there was no enrollment of children with special needs there, totalizing 46 children in processes of educational inclusion. From those, twelve children (26.8% were benefited with an Early Stimulation service maintained by the Association of Parents and Friends of Exceptional Children of that referred municipality, Thirty children (65,2% enrolled in school at the initiative of his own family e four children (8% by intervention of the Wakefield council. In this sense, we believe that the professionals of the Early Stimulation have the responsibility of promoting and conveying its importance and, mainly, the benefits of Early Stimulation for the whole development of individuals, as well as its contribution to a process of inclusive education.
Schlemm, Eckhard; 10.3150/10-BEJ329
2012-01-01
The class of multivariate L\\'{e}vy-driven autoregressive moving average (MCARMA) processes, the continuous-time analogs of the classical vector ARMA processes, is shown to be equivalent to the class of continuous-time state space models. The linear innovations of the weak ARMA process arising from sampling an MCARMA process at an equidistant grid are proved to be exponentially completely regular ($\\beta$-mixing) under a mild continuity assumption on the driving L\\'{e}vy process. It is verified that this continuity assumption is satisfied in most practically relevant situations, including the case where the driving L\\'{e}vy process has a non-singular Gaussian component, is compound Poisson with an absolutely continuous jump size distribution or has an infinite L\\'{e}vy measure admitting a density around zero.
A R Aithal; Rajesh Raut
2012-05-01
Let $\\wp 1,\\wp 0$ be two regular polygons of sides in a space form $M^2()$ of constant curvature =0,1 or -1 such that $\\wp 0\\subset\\wp 1$ and having the same center of mass. Suppose $\\wp 0$ is circumscribed by a circle contained in $\\wp 1$. We fix $\\wp 1$ and vary $\\wp 0$ by rotating it in about its center of mass. Put $ =(\\wp 1\\backslash\\wp 0)^0$, the interior of $\\wp 1\\backslash\\wp 0$ in $M^2()$. It is shown that the first Dirichlet’s eigenvalue 1() attains extremum when the axes of symmetry of $\\wp 0$ coincide with those of $\\wp 1$.
van Enter, Aernout C. D.; Fernández, Roberto; Sokal, Alan D.
1993-09-01
We reconsider the conceptual foundations of the renormalization-group (RG) formalism, and prove some rigorous theorems on the regularity properties and possible pathologies of the RG map. Our main results apply to local (in position space) RG maps acting on systems of bounded spins (compact single-spin space). Regarding regularity, we show that the RG map, defined on a suitable space of interactions (=formal Hamiltonians), is always single-valued and Lipschitz continuous on its domain of definition. This rules out a recently proposed scenario for the RG description of first-order phase transitions. On the pathological side, we make rigorous some arguments of Griffiths, Pearce, and Israel, and prove in several cases that the renormalized measure is not a Gibbs measure for any reasonable interaction. This means that the RG map is ill-defined, and that the conventional RG description of first-order phase transitions is not universally valid. For decimation or Kadanoff transformations applied to the Ising model in dimension d⩾3, these pathologies occur in a full neighborhood { β> β 0, ¦h¦< ɛ( β)} of the low-temperature part of the first-order phase-transition surface. For block-averaging transformations applied to the Ising model in dimension d⩾2, the pathologies occur at low temperatures for arbitrary magnetic field strength. Pathologies may also occur in the critical region for Ising models in dimension d⩾4. We discuss the heuristic and numerical evidence on RG pathologies in the light of our rigorous theorems. In addition, we discuss critically the concept of Gibbs measure, which is at the heart of present-day classical statistical mechanics. We provide a careful, and, we hope, pedagogical, overview of the theory of Gibbsian measures as well as (the less familiar) non-Gibbsian measures, emphasizing the distinction between these two objects and the possible occurrence of the latter in different physical situations. We give a rather complete catalogue of
Computably regular topological spaces
Weihrauch, Klaus
2013-01-01
This article continues the study of computable elementary topology started by the author and T. Grubba in 2009 and extends the author's 2010 study of axioms of computable separation. Several computable T3- and Tychonoff separation axioms are introduced and their logical relation is investigated. A number of implications between these axioms are proved and several implications are excluded by counter examples, however, many questions have not yet been answered. Known results on computable metr...
Global Positioning System-Based Stimulation for Robo-Pigeons in Open Space
Junqing Yang
2017-08-01
Full Text Available An evaluation method is described that will enable researchers to study fight control characteristics of robo-pigeons in fully open space. It is not limited by the experimental environment and overcomes environmental interference with flight control in small experimental spaces using a compact system. The system consists of two components: a global positioning system (GPS-based stimulator with dimensions of 38 mm × 26 mm × 8 mm and a weight of 18 g that can easily be carried by a pigeon as a backpack and a PC-based program developed in Virtual C++. The GPS-based stimulator generates variable stimulation and automatically records the GPS data and stimulus parameters. The PC-based program analyzes the recorded data and displays the flight trajectory of the tested robo-pigeon on a digital map. This method enables quick and clear evaluation of the flight control characteristics of a robo-pigeon in open space based on its visual trajectory, as well as further optimization of the microelectric stimulation parameters to improve the design of robo-pigeons. The functional effectiveness of the method was investigated and verified by performing flight control experiments using a robo-pigeon in open space.
Areej M. Abduldaim
2013-01-01
Full Text Available We introduced and studied -regular modules as a generalization of -regular rings to modules as well as regular modules (in the sense of Fieldhouse. An -module is called -regular if for each and , there exist and a positive integer such that . The notion of -pure submodules was introduced to generalize pure submodules and proved that an -module is -regular if and only if every submodule of is -pure iff is a -regular -module for each maximal ideal of . Many characterizations and properties of -regular modules were given. An -module is -regular iff is a -regular ring for each iff is a -regular ring for finitely generated module . If is a -regular module, then .
Lamberts, Agneta Luciana Matthanja (Thanja)
2015-01-01
This thesis is devoted to the study of regular and deuterated water in ices and on surfaces against an interstellar background. A large network for the formation of regular water has been studied with the use of a Kinetic Monte Carlo model. A specific reaction has been investigated as well: H2 + O -
Soga, Kouichi; Wakabayashi, Kazuyuki; Kamisaka, Seiichiro; Hoson, Takayuki
2002-10-01
Seedlings of Arabidopsis thaliana (L.) Heynh. (ecotype Columbia and an ethylene-resistant mutant etr1-1) were cultivated for 68.5, 91.5 and 136 h on board during the Space Shuttle STS-95 mission, and changes in the elongation growth and the cell wall properties of hypocotyls were analyzed. Elongation growth of dark-grown hypocotyls of both Columbia and etr1-1 was stimulated under microgravity conditions in space. There were no clear differences in the degree of growth stimulation between Columbia and etr1-1, indicating that the ethylene level was not abnormally high in the cultural environment of this space experiment. Microgravity also increased the mechanical extensibility of cell walls in both cultivars, and such an increase was attributed to the increase in the apparent irreversible extensibility. The levels of cell wall polysaccharides per unit length of hypocotyls decreased in space. Microgravity also reduced the weight-average molecular mass of xyloglucans in the hemicellulose-II fraction. Also, the activity of xyloglucan-degrading enzymes extracted from hypocotyl cell walls increased under microgravity conditions. These results suggest that microgravity reduces the molecular mass of xyloglucans by increasing xyloglucan-degrading activity. Modifications of xyloglucan metabolism as well as the thickness of cell wall polysaccharides seem to be involved in an increase in the cell wall extensibility, leading to growth stimulation of Arabidopsis hypocotyls in space.
Inclusive Regular Separation in L-Fuzzy Topological Spaces%L-fuzzy拓扑空间中的包含式正则分离性
赵彬
2005-01-01
In this paper, we first introduce the concept of the inclusive regular separation in L-fuzzy topological spaces. Then we compare the inclusive regular separation with pointed regular separation and regular separation, and discuss the implicative and non-implicative relations among the above three separations. Finally, we illustrate that the inclusive regular separation is harmonic with the inclusive normal separation and inclusive completely regular separation.%本文首先在一般L-fuzzy拓扑空间中引入了包含式正则分离性的概念.其次将包含式正则分离性与点式正则分离性及正则分离性作了比较,讨论了它们之间的相互蕴含关系.最后说明了包含式正则分离性与包含式正规分离性及包含式完全正则分离性之间的协调性.
Lipparini, Paolo
2008-01-01
We generalize the results from "P. Lipparini, Productive $[\\lambda,\\mu]$-compactness and regular ultrafilters, Topology Proceedings, 21 (1996), 161--171"; in particular the present results apply to singular cardinals, too.
Regularization in kernel learning
Mendelson, Shahar; 10.1214/09-AOS728
2010-01-01
Under mild assumptions on the kernel, we obtain the best known error rates in a regularized learning scenario taking place in the corresponding reproducing kernel Hilbert space (RKHS). The main novelty in the analysis is a proof that one can use a regularization term that grows significantly slower than the standard quadratic growth in the RKHS norm.
Carneiro, D F; Sampaio, M D; Nemes, M C
2003-01-01
We compute the three loop $\\beta$ function of the Wess-Zumino model to motivate implicit regularization (IR) as a consistent and practical momentum-space framework to study supersymmetric quantum field theories. In this framework which works essentially in the physical dimension of the theory we show that ultraviolet are clearly disantangled from infrared divergences. We obtain consistent results which motivate the method as a good choice to study supersymmetry anomalies in quantum field theories.
Paparó, M; Hareter, M; Guzik, J A
2016-01-01
A sequence search method was developed for searching for regular frequency spacing in delta Scuti stars by visual inspection and algorithmic search. The sample contains 90 delta Scuti stars observed by CoRoT. An example is given to represent the visual inspection. The algorithm (SSA) is described in detail. The data treatment of the CoRoT light curves, the criteria for frequency filtering and the spacings derived by two methods (three approaches: VI, SSA and FT) are given for each target. Echelle diagrams are presented for 77 targets, for which at least one sequence of regular spacing was identified. Comparing the spacing and the shifts between pairs of echelle ridges revealed that at least one pair of echelle ridges is shifted to midway between the spacing for 22 stars. The estimated rotational frequencies compared to the shifts revealed rotationally split doublets, triplets and multiplets not only for single frequencies, but for the complete echelle ridges in 31 delta Scuti stars. Using several possible ass...
Pavlov, Y V
2001-01-01
One derived expressions for the vacuum mean values of energy-momentum tensor of the scalar field with arbitrary relation to curvature in N-dimensional quasi-euclidean space-time for vacuum. One generalized n-wave procedure for multidimensional spaces. One calculated all counter-members for N=5 and for a conformal scalar field in N=6, 7. One determined the geometric structure of three first counter-members for N-dimensional spaces. All subtractions in 4-dimensional space-time and 3 first subtractions in multidimensional spaces are shown to correspond to renormalization of constants of priming and gravitational Lagrangian
Kumagai, Tomo' omi; Mudd, Ryan; Miyazawa, Yoshiyuki; Liu, Wen; Giambelluca, Thomas; Kobayashi, N.; Lim, Tiva Khan; Jomura, Mayuko; Matsumoto, Kazuho; Huang, Maoyi; Chen, Qi; Ziegler, Alan; Yin, Song
2013-09-10
We developed a soil-vegetation-atmosphere transfer (SVAT) model applicable to simulating CO2 and H2O fluxes from the canopies of rubber plantations, which are characterized by distinct canopy clumping produced by regular spacing of plantation trees. Rubber (Hevea brasiliensis Müll. Arg.) plantations, which are rapidly expanding into both climatically optimal and sub-optimal environments throughout mainland Southeast Asia, potentially change the partitioning of water, energy, and carbon at multiple scales, compared with traditional land covers it is replacing. Describing the biosphere-atmosphere exchange in rubber plantations via SVAT modeling is therefore essential to understanding the impacts on environmental processes. The regular spacing of plantation trees creates a peculiar canopy structure that is not well represented in most SVAT models, which generally assumes a non-uniform spacing of vegetation. Herein we develop a SVAT model applicable to rubber plantation and an evaluation method for its canopy structure, and examine how the peculiar canopy structure of rubber plantations affects canopy CO2 and H2O exchanges. Model results are compared with measurements collected at a field site in central Cambodia. Our findings suggest that it is crucial to account for intensive canopy clumping in order to reproduce observed rubber plantation fluxes. These results suggest a potentially optimal spacing of rubber trees to produce high productivity and water use efficiency.
Augmenting LTP-Like Plasticity in Human Motor Cortex by Spaced Paired Associative Stimulation.
Florian Müller-Dahlhaus
Full Text Available Paired associative stimulation (PASLTP of the human primary motor cortex (M1 can induce LTP-like plasticity by increasing corticospinal excitability beyond the stimulation period. Previous studies showed that two consecutive PASLTP protocols interact by homeostatic metaplasticity, but animal experiments provided evidence that LTP can be augmented by repeated stimulation protocols spaced by ~30 min. Here we tested in twelve healthy selected PASLTP responders the possibility that LTP-like plasticity can be augmented in the human M1 by systematically varying the interval between two consecutive PASLTP protocols. The first PASLTP protocol (PAS1 induced strong LTP-like plasticity lasting for 30-60 min. The effect of a second identical PASLTP protocol (PAS2 critically depended on the time between PAS1 and PAS2. At 10 min, PAS2 prolonged the PAS1-induced LTP-like plasticity. At 30 min, PAS2 augmented the LTP-like plasticity induced by PAS1, by increasing both magnitude and duration. At 60 min and 180 min, PAS2 had no effect on corticospinal excitability. The cumulative LTP-like plasticity after PAS1 and PAS2 at 30 min exceeded significantly the effect of PAS1 alone, and the cumulative PAS1 and PAS2 effects at 60 min and 180 min. In summary, consecutive PASLTP protocols interact in human M1 in a time-dependent manner. If spaced by 30 min, two consecutive PASLTP sessions can augment LTP-like plasticity in human M1. Findings may inspire further research on optimized therapeutic applications of non-invasive brain stimulation in neurological and psychiatric diseases.
Augmenting LTP-Like Plasticity in Human Motor Cortex by Spaced Paired Associative Stimulation.
Müller-Dahlhaus, Florian; Lücke, Caroline; Lu, Ming-Kuei; Arai, Noritoshi; Fuhl, Anna; Herrmann, Eva; Ziemann, Ulf
2015-01-01
Paired associative stimulation (PASLTP) of the human primary motor cortex (M1) can induce LTP-like plasticity by increasing corticospinal excitability beyond the stimulation period. Previous studies showed that two consecutive PASLTP protocols interact by homeostatic metaplasticity, but animal experiments provided evidence that LTP can be augmented by repeated stimulation protocols spaced by ~30 min. Here we tested in twelve healthy selected PASLTP responders the possibility that LTP-like plasticity can be augmented in the human M1 by systematically varying the interval between two consecutive PASLTP protocols. The first PASLTP protocol (PAS1) induced strong LTP-like plasticity lasting for 30-60 min. The effect of a second identical PASLTP protocol (PAS2) critically depended on the time between PAS1 and PAS2. At 10 min, PAS2 prolonged the PAS1-induced LTP-like plasticity. At 30 min, PAS2 augmented the LTP-like plasticity induced by PAS1, by increasing both magnitude and duration. At 60 min and 180 min, PAS2 had no effect on corticospinal excitability. The cumulative LTP-like plasticity after PAS1 and PAS2 at 30 min exceeded significantly the effect of PAS1 alone, and the cumulative PAS1 and PAS2 effects at 60 min and 180 min. In summary, consecutive PASLTP protocols interact in human M1 in a time-dependent manner. If spaced by 30 min, two consecutive PASLTP sessions can augment LTP-like plasticity in human M1. Findings may inspire further research on optimized therapeutic applications of non-invasive brain stimulation in neurological and psychiatric diseases.
Scales, W. A.
2016-02-01
Investigation of stimulated radiation, commonly known as stimulated electromagnetic emissions (SEE), produced by the interaction of high-power, high-frequency HF radiowaves with the ionospheric plasma has been a vibrant area of research since the early 1980s. Substantial diagnostic information about ionospheric plasma characteristics, dynamics, and turbulence can be obtained from the frequency spectrum of the stimulated radiation. During the past several decades, so-called wideband SEE which exists in a frequency band of ±100 kHz or so of the transmit wave frequency (which is several MHz) has been investigated relatively thoroughly. Recent upgrades both in transmitter power and diagnostic receiver frequency sensitivity at major ionosphere interaction facilities in Alaska and Norway have allowed new breakthroughs in the ability to study a plethora of processes associated with the ionospheric plasma during these experiments. A primary advance is in observations of so-called narrowband SEE (NSEE) which exists roughly within ±1 kHz of the transmit wave frequency. An overview of several important new results associated with NSEE are discussed as well as implications to new diagnostics of space plasma physics occurring during ionospheric interaction experiments.
Hoson, T; Soga, K; Wakabayashi, K; Hashimoto, T; Karahara, I; Yano, S; Tanigaki, F; Shimazu, T; Kasahara, H; Masuda, D; Kamisaka, S
2014-01-01
Cortical microtubules are involved in plant resistance to hypergravity, but their roles in resistance to 1 g gravity are still uncertain. To clarify this point, we cultivated an Arabidopsis α-tubulin 6 mutant (tua6) in the Cell Biology Experiment Facility on the Kibo Module of the International Space Station, and analyzed growth and cell wall mechanical properties of inflorescences. Growth of inflorescence stems was stimulated under microgravity conditions, as compared with ground and on-orbit 1 g conditions. The stems were 10-45% longer and their growth rate 15-55% higher under microgravity conditions than those under both 1 g conditions. The degree of growth stimulation tended to be higher in the tua6 mutant than the wild-type Columbia. Under microgravity conditions, the cell wall extensibility in elongating regions of inflorescences was significantly higher than the controls, suggesting that growth stimulation was caused by cell wall modifications. No clear differences were detected in any growth or cell wall property between ground and on-orbit 1 g controls. These results support the hypothesis that cortical microtubules generally play an important role in plant resistance to the gravitational force.
T. (A)LVAREZ
2012-01-01
For a closed linear relation in a Banach space the concept of regularity is introduced and studied.It is shown that many of the results of Mbekhta and other authors for operators remain valid in the context of multivalued linear operators.We also extend the punctured neighbourhood theorem for operators to linear relations and as an application we obtain a characterization of semiFredholm linear relations which are regular.
Lipparini, Paolo
2008-01-01
We find many conditions equivalent to the model-theoretical property $\\lambda \\stackrel{\\kappa}{\\Rightarrow} \\mu$ introduced in [L1]. Our conditions involve uniformity of ultrafilters, compactness properties of products of topological spaces and the existence of certain infinite matrices.
Alpha stimulation of the human parietal cortex attunes tactile perception to external space.
Ruzzoli, Manuela; Soto-Faraco, Salvador
2014-02-03
An intriguing question in neuroscience concerns how somatosensory events on the skin are represented in the human brain. Since Head and Holmes' [1] neuropsychological dissociation between localizing touch on the skin and localizing body parts in external space, touch is considered to operate in a variety of spatial reference frames [2]. At least two representations of space are in competition during orienting to touch: a somatotopic one, reflecting the organization of the somatosensory cortex (S1) [3], and a more abstract, external reference frame that factors postural changes in relation to body parts and/or external space [4, 5]. Previous transcranial magnetic stimulation (TMS) studies suggest that the posterior parietal cortex (PPC) plays a key role in supporting representations as well as orienting attention in an external reference frame [4, 6]. Here, we capitalized on the TMS entrainment approach [7, 8], targeting the intraparietal sulcus (IPS). We found that frequency-specific (10 Hz) tuning of the PPC induced spatially specific enhancement of tactile detection that was expressed in an external reference frame. This finding establishes a tight causal link between a concrete form of brain activity (10 Hz oscillation) and a specific type of spatial representation, revealing a fundamental property of how the parietal cortex encodes information.
李兴校; 宋虹儒
2016-01-01
In this paper, we introduce two conformal non-homogeneous coordinate systems. Modeled on the de Sitter space Sm+11 , we cover the conformal space Qm+11 . The conformal geometry of regular space-like hypersurfaces in Qm+11 can be treated as in the M¨obius geometry of hyper-surfaces in the sphere Sm+1. As a result, we give a complete classification of the regular space-like hypersurfaces with parallel Blaschke tensors.%本文引入两个以de Sitter空间为模型的非齐性坐标来覆盖共形空间Qm+11.利用球面Sm+1中超曲面的M¨obius 几何的方法，本文研究了Qm+11中正则类空超曲面的共形几何.作为其结果，本文对所有具有平行Blaschke张量的正则类空超曲面进行了完全分类.
Sidtis, John J; Alken, Amy G; Tagliati, Michele; Alterman, Ron; Van Lancker Sidtis, Diana
2016-03-19
Stimulation of the subthalamic nuclei (STN) is an effective treatment for Parkinson's disease, but complaints of speech difficulties after surgery have been difficult to quantify. Speech measures do not convincingly account for such reports. This study examined STN stimulation effects on vowel production, in order to probe whether DBS affects articulatory posturing. The objective was to compare positioning during the initiation phase with the steady prolongation phase by measuring vowel spaces for three "corner" vowels at these two time frames. Vowel space was measured over the initial 0.25 sec of sustained productions of high front (/i/), high back (/u/) and low vowels (/a/), and again during a 2 sec segment at the midpoint. Eight right-handed male subjects with bilateral STN stimulation and seven age-matched male controls were studied based on their participation in a larger study that included functional imaging. Mean values: age = 57±4.6 yrs; PD duration = 12.3±2.7 yrs; duration of DBS = 25.6±21.2 mos, and UPDRS III speech score = 1.6±0.7. STN subjects were studied off medication at their therapeutic DBS settings and again with their stimulators off, counter-balanced order. Vowel space was larger in the initiation phase compared to the midpoint for both the control and the STN subjects off stimulation. With stimulation on, however, the initial vowel space was significantly reduced to the area measured at the mid-point. For the three vowels, the acoustics were differentially affected, in accordance with expected effects of front versus back position in the vocal tract. STN stimulation appears to constrain initial articulatory gestures for vowel production, raising the possibility that articulatory positions normally used in speech are similarly constrained.
Hansen, Lars Kai; Rasmussen, Carl Edward; Svarer, C.
1994-01-01
Regularization, e.g., in the form of weight decay, is important for training and optimization of neural network architectures. In this work the authors provide a tool based on asymptotic sampling theory, for iterative estimation of weight decay parameters. The basic idea is to do a gradient descent...... in the estimated generalization error with respect to the regularization parameters. The scheme is implemented in the authors' Designer Net framework for network training and pruning, i.e., is based on the diagonal Hessian approximation. The scheme does not require essential computational overhead in addition...... to what is needed for training and pruning. The viability of the approach is demonstrated in an experiment concerning prediction of the chaotic Mackey-Glass series. The authors find that the optimized weight decays are relatively large for densely connected networks in the initial pruning phase, while...
Coxeter, H S M
1973-01-01
Polytopes are geometrical figures bounded by portions of lines, planes, or hyperplanes. In plane (two dimensional) geometry, they are known as polygons and comprise such figures as triangles, squares, pentagons, etc. In solid (three dimensional) geometry they are known as polyhedra and include such figures as tetrahedra (a type of pyramid), cubes, icosahedra, and many more; the possibilities, in fact, are infinite! H. S. M. Coxeter's book is the foremost book available on regular polyhedra, incorporating not only the ancient Greek work on the subject, but also the vast amount of information
Manifold Regularized Reinforcement Learning.
Li, Hongliang; Liu, Derong; Wang, Ding
2017-01-27
This paper introduces a novel manifold regularized reinforcement learning scheme for continuous Markov decision processes. Smooth feature representations for value function approximation can be automatically learned using the unsupervised manifold regularization method. The learned features are data-driven, and can be adapted to the geometry of the state space. Furthermore, the scheme provides a direct basis representation extension for novel samples during policy learning and control. The performance of the proposed scheme is evaluated on two benchmark control tasks, i.e., the inverted pendulum and the energy storage problem. Simulation results illustrate the concepts of the proposed scheme and show that it can obtain excellent performance.
Constrained and regularized system identification
Tor A. Johansen
1998-04-01
Full Text Available Prior knowledge can be introduced into system identification problems in terms of constraints on the parameter space, or regularizing penalty functions in a prediction error criterion. The contribution of this work is mainly an extension of the well known FPE (Final Production Error statistic to the case when the system identification problem is constrained and contains a regularization penalty. The FPECR statistic (Final Production Error with Constraints and Regularization is of potential interest as a criterion for selection of both regularization parameters and structural parameters such as order.
Zhang Lianshan; Deng Xianhe; Liu Weitao; Yang Zhiping
2014-01-01
The natural convection heat transfer of a 60%sucrose solution in a vertical converging-diverging tube (CD) with regularly-spaced twisted tapes (RSTT) has been investigated numerically and experimentally. The effects of wall tempera-ture and number of RSTT on the Nusselt number were studied in detail. The distributions of velocity and temperature in the 60%sucrose solution were studied and the simulated results of CD with RSTT were compared with those of the smooth tube. The inlfuence of Rayleigh number and RSTT on the Nusselt number was conducted experimentally. The results indi-cate that the Nusselt number of the 60%sucrose solution obviously increased with the number of RSTT but increased in-conspicuously with 2 and more twisted tapes. The simulation shows that the distance for achieving an optimal heat transfer performance is 46 times the diameter of the tube. The mechanism of the natural convection heat transfer enhancement of the 60%sucrose solution in relationship with the CD and the RSTT was analyzed, and the change of average tangential velocity with the axial distance was presented to demonstrate that the enhancement of heat transfer was realized mainly because of the increase in tangential velocity.
Recursively-regular subdivisions and applications
Rafel Jaume
2016-05-01
Full Text Available We generalize regular subdivisions (polyhedral complexes resulting from the projection of the lower faces of a polyhedron introducing the class of recursively-regular subdivisions. Informally speaking, a recursively-regular subdivision is a subdivision that can be obtained by splitting some faces of a regular subdivision by other regular subdivisions (and continue recursively. We also define the finest regular coarsening and the regularity tree of a polyhedral complex. We prove that recursively-regular subdivisions are not necessarily connected by flips and that they are acyclic with respect to the in-front relation. We show that the finest regular coarsening of a subdivision can be efficiently computed, and that whether a subdivision is recursively regular can be efficiently decided. As an application, we also extend a theorem known since 1981 on illuminating space by cones and present connections of recursive regularity to tensegrity theory and graph-embedding problems.
Lu, Jinying; Liu, Min; Pan, Yi; Li, Huasheng
We carried out whole-genome microarray to screen the transcript profile of Arabidopsis thaliana seedlings after three treatment: space microgravity condition( Seedlings grown in microgravity state of space flight of SIMBOX on Shenzhou-8), 1g centrifugal force in space(Seedlings grown in 1g centrifugal force state of space flight of SIMBOX on Shenzhou-8) and ground control. The result of microarray analysis is as followed: There were 368 genes significantly differentially expressed in space microgravity condition compared with that in 1g centrifuge space condition. Space radiation caused 246 genes significantly differentially expressed between seedlings in 1g centrifuge space condition and ground control. Space conditions (including microgravity and radiation) caused 621 genes significantly differentially expressed between seedlings in space microgravity condition and ground control. Microgravity and radiation as a single factor can cause plant gene expression change, but two factors synergism can produce some new effects on plant gene expression. The function of differential expression genes were analyst by bioinformatics, and we found the expression of genes related with stress were more different, such as the dehydration of protein (dehydrin Xero2) expression is up-regulated 57 times; low-temperature-induced protein expression is up-regulated in 49 times; heat shock protein expression is up-regulated 20 times; transcription factor DREB2A expression increase 25 times; protein phosphatase 2C expression is up-regulated 14 times; transcription factor NAM-like protein expression is up-regulated 13 times; cell wall metabolism related genes (xyloglucan, endo-1, 4-beta-D-glucanase) expression is down-regulated in 15 times. The results provide scientific data for the mechanism of space mutation.
Perceptual space induced by cochlear implant all-polar stimulation mode
Marozeau, Jeremy; Mckay, Colette M.
2015-01-01
It has often been argued that a main limitation of the cochlear implant is the spread of current induced by each electrode, which activates an inappropriately large range of sensory neurons. In order to reduce this spread, a new stimulation mode, the all-polar mode, was tested with 5 participants...
The paradox of systemic vasodilatation and sympathetic nervous stimulation in space
Norsk, Peter; Christensen, Niels Juel
2009-01-01
decreased by 5mmHg. This is in accordance with observations that very acute weightlessness during parabolic airplane flights and a week of weightlessness in space leads to a decrease in systemic vascular resistance. That the arterial resistance vessels are dilated in space is in contrast to the augmented...
Studies of plant gene expression and function stimulated by space microgravity
Lu, Jinying; Liu, Min; Li, Huasheng; Zhao, Hui
2016-07-01
One of the important questions in space biology is how plants respond to an outer space environment i.e., how genetic expression is altered in space microgravity. In this study, the transcriptome of Arabidopsis thaliana seedlings was analyzed as part of the Germany SIMBOX (Science in Microgravity Box) spaceflight experiment on Shenzhou 8. A gene chip was used to screen gene expression differences in Arabidopsis thaliana seedlings between microgravity and 1g centrifugal force in space. Microarray analysis revealed that 368 genes were differentially expressed. Gene Ontology (GO) analysis indicated that these genes were involved in the plant's response to stress, secondary metabolism, hormone metabolism, transcription, protein phosphorylation, lipid metabolism, transport and cell wall metabolism processes. Real time PCR was used to analyzed the miRNA expression including Arabidopsis miR160,miR161, miR394, miR402, miR403, and miR408. MiR408 was significantly upregulated. An overexpression vector of Arabidopsis miR408 was constructed and transferred to Arabidopsis plant. The roots of plants over expressing miR408 exhibited a slower reorientation upon gravistimulation in comparison with those of wild-type. This result indicated that miR408 could play a role in root gravitropic response.
Central charges in regular mechanics
Cabo-Montes de Oca, Alejandro; Villanueva, V M
1997-01-01
We consider the algebra associated to a group of transformations which are symmetries of a regular mechanical system (i.e. system free of constraints). For time dependent coordinate transformations we show that a central extension may appear at the classical level which is coordinate and momentum independent. A cochain formalism naturally arises in the argument and extends the usual configuration space cochain concepts to phase space.
Baisch, F.; Beck, L.; Blomqvist, G.; Wolfram, G.; Drescher, J.; Rome, J. L.; Drummer, C.
2000-01-01
BACKGROUND: It is well known that space travel cause post-flight orthostatic hypotension and it was assumed that autonomic cardiovascular control deteriorates in space. Lower body negative pressure (LBNP) was used to assess autonomic function of the cardiovascular system. METHODS: LBNP tests were performed on six crew-members before and on the first days post-flight in a series of three space missions. Additionally, two of the subjects performed LBNP tests in-flight. LBNP mimics fluid distribution of upright posture in a gravity independent way. It causes an artificial sequestration of blood, reduces preload, and filtrates plasma into the lower part of the body. Fluid distribution was assessed by bioelectrical impedance and anthropometric measurements. RESULTS: Heart rate, blood pressure, and total peripheral resistance increased significantly during LBNP experiments in-flight. The decrease in stroke volume, the increased pooling of blood, and the increased filtration of plasma into the lower limbs during LBNP indicated that a plasma volume reduction and a deficit of the interstitial volume of lower limbs rather than a change in cardiovascular control was responsible for the in-flight response. Post-flight LBNP showed no signs of cardiovascular deterioration. The still more pronounced haemodynamic changes during LBNP reflected the expected behaviour of cardiovascular control faced with less intravascular volume. In-flight, the status of an intra-and extravascular fluid deficit increases sympathetic activity, the release of vasoactive substances and consequently blood pressure. Post-flight, blood pressure decreases significantly below pre-flight values after restoration of volume deficits. CONCLUSION: We conclude that the cardiovascular changes in-flight are a consequence of a fluid deficit rather than a consequence of changes in autonomic signal processing.
Yong Hua LI; Hai Bin KAN; Bing Jun YU
2004-01-01
In this paper, a special kind of partial algebras called projective partial groupoids is defined.It is proved that the inverse image of all projections of a fundamental weak regular *-semigroup under the homomorphism induced by the maximum idempotent-separating congruence of a weak regular *-semigroup has a projective partial groupoid structure. Moreover, a weak regular *-product which connects a fundamental weak regular *-semigroup with corresponding projective partial groupoid is defined and characterized. It is finally proved that every weak regular *-product is in fact a weak regular *-semigroup and any weak regular *-semigroup is constructed in this way.
Yildiz, Cemil; ABBAS, Fadhil
2011-01-01
The concepts of fuzzy regular-I-closed set and fuzzy semi-I-regular set in fuzzy ideal topological spaces are investigated and some of their properties are obtained. Key words: Topological, Spaces, Fuzzy, Regular, Sets
张涛; 洪文学
2012-01-01
在计算几何组合分类器中,子分类器的权重分配一直未能充分利用空间视觉信息,使得分类器的可视化特性无法完全得到发挥.本文从类空间类别分布特性出发,提出基于类空间规整度的权重分配方法.该方法首先将子分类器由空间的类别表示转变为类别的空间表示,进而利用共生原则分析不同类别在空间中的分布规整度.由于分布规整度为类别分布信息的整体体现,可以用于刻画类空间中不同类别样本的离散程度,因此可以利用当前类空间的规整度信息作为该子分类器的权重.实验表明,利用规整度信息进行加权后的分类器不但与可视化特性更好的吻合,增强了分类过程的可理解性,而且在分类精度上得到了进一步的提升,扩展了应用领域.%In all the tissues about computational geometry combining classifier, the weight calculation for sub classifiers has not taken the advantage of visual information in the spaces, which retains the visual performance about classifier. According to the category distribution in class space, a weight calculation method based on space regulation is proposed. In this method, the space is turned from category information in space to space information in category. And the space regularity is obtained from the later based on co occur rules. As the regularity reflects the distribution of categories and describes the separation of the samples, which makes it as the weight for the sub classifier. The experiments show that the classifier weighted by the regularity not only enhance the visual performance, but also the classify performance of the classifier. It means that the comprehensibility of the classifier is enhanced and the application of the classifier is extended.
Regular Bases At Non-isolated Points And Metrization Theorems
Lin, Fucai; Junnila, Heikki
2011-01-01
In this paper, we define the spaces with a regular base at non-isolated points and discuss some metrization theorems. We firstly show that a space $X$ is a metrizable space, if and only if $X$ is a regular space with a $\\sigma$-locally finite base at non-isolated points, if and only if $X$ is a perfect space with a regular base at non-isolated points, if and only if $X$ is a $\\beta$-space with a regular base at non-isolated points. In addition, we also discuss the relations between the spaces with a regular base at non-isolated points and some generalized metrizable spaces. Finally, we give an affirmative answer for a question posed by F. C. Lin and S. Lin in \\cite{LL}, which also shows that a space with a regular base at non-isolated points has a point-countable base.
Sidtis, John J.; Alken, Amy G.; Tagliati, Michele; Alterman, Ron; Van Lancker Sidtis, Diana
2016-01-01
Background: Stimulation of the subthalamic nuclei (STN) is an effective treatment for Parkinson’s disease, but complaints of speech difficulties after surgery have been difficult to quantify. Speech measures do not convincingly account for such reports. Objective: This study examined STN stimulation effects on vowel production, in order to probe whether DBS affects articulatory posturing. The objective was to compare positioning during the initiation phase with the steady prolongation phase by measuring vowel spaces for three “corner” vowels at these two time frames. Methods: Vowel space was measured over the initial 0.25 sec of sustained productions of high front (/i/), high back (/u/) and low vowels (/a/), and again during a 2 sec segment at the midpoint. Eight right-handed male subjects with bilateral STN stimulation and seven age-matched male controls were studied based on their participation in a larger study that included functional imaging. Mean values: age = 57±4.6 yrs; PD duration = 12.3±2.7 yrs; duration of DBS = 25.6±21.2 mos, and UPDRS III speech score = 1.6±0.7. STN subjects were studied off medication at their therapeutic DBS settings and again with their stimulators off, counter-balanced order. Results: Vowel space was larger in the initiation phase compared to the midpoint for both the control and the STN subjects off stimulation. With stimulation on, however, the initial vowel space was significantly reduced to the area measured at the mid-point. For the three vowels, the acoustics were differentially affected, in accordance with expected effects of front versus back position in the vocal tract. Conclusions: STN stimulation appears to constrain initial articulatory gestures for vowel production, raising the possibility that articulatory positions normally used in speech are similarly constrained. PMID:27003219
NOETHERIAN GR-REGULAR RINGS ARE REGULAR
LIHUISHI
1994-01-01
It is proved that for a left Noetherian z-graded ring A,if every finitely generated graded A-module has finite projective dimension(i.e-,A is gr-regular)then every finitely generated A-module has finite projective dimension(i.e.,A is regular).Some applications of this result to filtered rings and some classical cases are also given.
Regular Expression Pocket Reference
Stubblebine, Tony
2007-01-01
This handy little book offers programmers a complete overview of the syntax and semantics of regular expressions that are at the heart of every text-processing application. Ideal as a quick reference, Regular Expression Pocket Reference covers the regular expression APIs for Perl 5.8, Ruby (including some upcoming 1.9 features), Java, PHP, .NET and C#, Python, vi, JavaScript, and the PCRE regular expression libraries. This concise and easy-to-use reference puts a very powerful tool for manipulating text and data right at your fingertips. Composed of a mixture of symbols and text, regular exp
Dimensional regularization is generic
Fujikawa, Kazuo
2016-01-01
The absence of the quadratic divergence in the Higgs sector of the Standard Model in the dimensional regularization is usually regarded to be an exceptional property of a specific regularization. To understand what is going on in the dimensional regularization, we illustrate how to reproduce the results of the dimensional regularization for the $\\lambda\\phi^{4}$ theory in the more conventional regularization such as the higher derivative regularization; the basic postulate involved is that the quadratically divergent induced mass, which is independent of the scale change of the physical mass, is kinematical and unphysical. This is consistent with the derivation of the Callan-Symanzik equation, which is a comparison of two theories with slightly different masses, for the $\\lambda\\phi^{4}$ theory without encountering the quadratic divergence. We thus suggest that the dimensional regularization is generic in a bottom-up approach starting with a successful low-energy theory. We also define a modified version of t...
Physical model of dimensional regularization
Schonfeld, Jonathan F.
2016-12-15
We explicitly construct fractals of dimension 4-ε on which dimensional regularization approximates scalar-field-only quantum-field theory amplitudes. The construction does not require fractals to be Lorentz-invariant in any sense, and we argue that there probably is no Lorentz-invariant fractal of dimension greater than 2. We derive dimensional regularization's power-law screening first for fractals obtained by removing voids from 3-dimensional Euclidean space. The derivation applies techniques from elementary dielectric theory. Surprisingly, fractal geometry by itself does not guarantee the appropriate power-law behavior; boundary conditions at fractal voids also play an important role. We then extend the derivation to 4-dimensional Minkowski space. We comment on generalization to non-scalar fields, and speculate about implications for quantum gravity. (orig.)
Ewert, Siobhan; Plettig, Philip; Li, Ningfei; Chakravarty, M Mallar; Collins, D Louis; Herrington, Todd M; Kühn, Andrea A; Horn, Andreas
2017-05-20
Three-dimensional atlases of subcortical brain structures are valuable tools to reference anatomy in neuroscience and neurology. For instance, they can be used to study the position and shape of the three most common deep brain stimulation (DBS) targets, the subthalamic nucleus (STN), internal part of the pallidum (GPi) and ventral intermediate nucleus of the thalamus (VIM) in spatial relationship to DBS electrodes. Here, we present a composite atlas based on manual segmentations of a multimodal high resolution brain template, histology and structural connectivity. In a first step, four key structures were defined on the template itself using a combination of multispectral image analysis and manual segmentation. Second, these structures were used as anchor points to coregister a detailed histological atlas into standard space. Results show that this approach significantly improved coregistration accuracy over previously published methods. Finally, a sub-segmentation of STN and GPi into functional zones was achieved based on structural connectivity. The result is a composite atlas that defines key nuclei on the template itself, fills the gaps between them using histology and further subdivides them using structural connectivity. We show that the atlas can be used to segment DBS targets in single subjects, yielding more accurate results compared to priorly published atlases. The atlas will be made publicly available and constitutes a resource to study DBS electrode localizations in combination with modern neuroimaging methods. Copyright © 2017 Elsevier Inc. All rights reserved.
Ensemble manifold regularization.
Geng, Bo; Tao, Dacheng; Xu, Chao; Yang, Linjun; Hua, Xian-Sheng
2012-06-01
We propose an automatic approximation of the intrinsic manifold for general semi-supervised learning (SSL) problems. Unfortunately, it is not trivial to define an optimization function to obtain optimal hyperparameters. Usually, cross validation is applied, but it does not necessarily scale up. Other problems derive from the suboptimality incurred by discrete grid search and the overfitting. Therefore, we develop an ensemble manifold regularization (EMR) framework to approximate the intrinsic manifold by combining several initial guesses. Algorithmically, we designed EMR carefully so it 1) learns both the composite manifold and the semi-supervised learner jointly, 2) is fully automatic for learning the intrinsic manifold hyperparameters implicitly, 3) is conditionally optimal for intrinsic manifold approximation under a mild and reasonable assumption, and 4) is scalable for a large number of candidate manifold hyperparameters, from both time and space perspectives. Furthermore, we prove the convergence property of EMR to the deterministic matrix at rate root-n. Extensive experiments over both synthetic and real data sets demonstrate the effectiveness of the proposed framework.
Limitations on Dimensional Regularization in Renyi Entropy
Bao, Ning
2016-01-01
Dimensional regularization is a common method used to regulate the UV divergence of field theoretic quantities. When it is used in the context of Renyi entropy, however, it is important to consider whether such a procedure eliminates the statistical interpretation thereof as a measure of entanglement of states living on a Hilbert space. We therefore examine the dimensionally regularized Renyi entropy of a 4d unitary CFT and show that it admits no underlying Hilbert space in the state-counting sense. This gives a concrete proof that dimensionally regularized Renyi entropy cannot always be obtained as a limit of the Renyi entropy of some finite-dimensional quantum system.
Robust Sparse Analysis Regularization
Vaiter, Samuel; Dossal, Charles; Fadili, Jalal
2011-01-01
This paper studies the properties of L1-analysis regularization for the resolution of linear inverse problems. Most previous works consider sparse synthesis priors where the sparsity is measured as the L1 norm of the coefficients that synthesize the signal in a given dictionary. In contrast, the more general analysis regularization minimizes the L1 norm of the correlations between the signal and the atoms in the dictionary. The corresponding variational problem includes several well-known regularizations such as the discrete total variation and the fused lasso. We first prove that a solution of analysis regularization is a piecewise affine function of the observations. Similarly, it is a piecewise affine function of the regularization parameter. This allows us to compute the degrees of freedom associated to sparse analysis estimators. Another contribution gives a sufficient condition to ensure that a signal is the unique solution of the analysis regularization when there is no noise in the observations. The s...
Goyvaerts, Jan
2009-01-01
This cookbook provides more than 100 recipes to help you crunch data and manipulate text with regular expressions. Every programmer can find uses for regular expressions, but their power doesn't come worry-free. Even seasoned users often suffer from poor performance, false positives, false negatives, or perplexing bugs. Regular Expressions Cookbook offers step-by-step instructions for some of the most common tasks involving this tool, with recipes for C#, Java, JavaScript, Perl, PHP, Python, Ruby, and VB.NET. With this book, you will: Understand the basics of regular expressions through a
Morrey Regularity of the Solution to the Dirichlet Problem
无
2000-01-01
@@To study the local regularity of solutions to second orderelliptic partial differential equations, Morrey in ［1］ introduced somefunction spaces, which are called the Morrey spaces today. Since then, manymathematicians have studied regularities of solutions to some kinds of secondorder elliptic equations in Morrey spaces.
Regular database update logics
Spruit, Paul; Wieringa, Roel; Meyer, John-Jules
2001-01-01
We study regular first-order update logic (FUL), which is a variant of regular dynamic logic in which updates to function symbols as well as to predicate symbols are possible. We fi1rst study FUL without making assumptions about atomic updates. Second, we look at relational algebra update logic (RAU
Optimal Regularizing Effect for Scalar Conservation Laws
Golse, François
2011-01-01
We investigate the regularity of bounded weak solutions of scalar conservation laws with uniformly convex flux in space dimension one, satisfying an entropy condition with entropy production term that is a signed Radon measure. The proof is based on the kinetic formulation of scalar conservation laws and on an interaction estimate in physical space.
Regularization by External Variables
Bossolini, Elena; Edwards, R.; Glendinning, P. A.
2016-01-01
Regularization was a big topic at the 2016 CRM Intensive Research Program on Advances in Nonsmooth Dynamics. There are many open questions concerning well known kinds of regularization (e.g., by smoothing or hysteresis). Here, we propose a framework for an alternative and important kind of regula...... of regularization, by external variables that shadow either the state or the switch of the original system. The shadow systems are derived from and inspired by various applications in electronic control, predator-prey preference, time delay, and genetic regulation....
Lackner, J. R.; Graybiel, A.
1986-01-01
The effect of gravity on the severity of the Coriolis-induced motion sickness was investigated in ten individuals subjected to high and low G-force phases of parabolic flight maneuvers using constant level Coriolis, cross-coupled angular acceleration stimulation. Using seven levels of severity in the diagnosis of motion sickness, it was found that the subjects were less susceptible at 0 G than at +2 Gz, and that the perceived intensity and provocativeness of Coriolis stimulation decreased in 0 G and increased in +2 Gz relative to the +1 Gz baseline values. The changes in the apparent intensity of Coriolis stimulation occur virtually immediately when the background gravitatioinertial force level is varied. These findings explain why the Skylab astronauts were refractory to motion sickness during Coriolis stimulation in-flight.
Regularized maximum correntropy machine
Wang, Jim Jing-Yan
2015-02-12
In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.
Regular Expression Containment
Henglein, Fritz; Nielsen, Lasse
2011-01-01
We present a new sound and complete axiomatization of regular expression containment. It consists of the conventional axiomatiza- tion of concatenation, alternation, empty set and (the singleton set containing) the empty string as an idempotent semiring, the fixed- point rule E* = 1 + E × E......* for Kleene-star, and a general coin- duction rule as the only additional rule. Our axiomatization gives rise to a natural computational inter- pretation of regular expressions as simple types that represent parse trees, and of containment proofs as coercions. This gives the axiom- atization a Curry......-Howard-style constructive interpretation: Con- tainment proofs do not only certify a language-theoretic contain- ment, but, under our computational interpretation, constructively transform a membership proof of a string in one regular expres- sion into a membership proof of the same string in another regular expression. We...
Kuan Hsien Lee
2016-02-01
Full Text Available How a stimulus impacts spinal cord function depends upon temporal relations. When intermittent noxious stimulation (shock is applied and the interval between shock pulses is varied (unpredictable, it induces a lasting alteration that inhibits adaptive learning. If the same stimulus is applied in a temporally regular (predictable manner, the capacity to learn is preserved and a protective/restorative effect is engaged that counters the adverse effect of variable stimulation. Sensitivity to temporal relations implies a capacity to encode time. This study explores how spinal neurons discriminate variable and fixed spaced stimulation. Communication with the brain was blocked by means of a spinal transection and adaptive capacity was tested using an instrumental learning task. In this task, subjects must learn to maintain a hind limb in a flexed position to minimize shock exposure. To evaluate the possibility that a distinct class of afferent fibers provide a sensory cue for regularity, we manipulated the temporal relation between shocks given to two dermatomes (leg and tail. Evidence for timing emerged when the stimuli were applied in a coherent manner across dermatomes, implying that a central (spinal process detects regularity. Next, we show that fixed spaced stimulation has a restorative effect when half the physical stimuli are randomly omitted, as long as the stimuli remain in phase, suggesting that stimulus regularity is encoded by an internal oscillator Research suggests that the oscillator that drives the tempo of stepping depends upon neurons within the rostral lumbar (L1-L2 region. Disrupting communication with the L1-L2 tissue by means of a L3 transection eliminated the restorative effect of fixed spaced stimulation. Implications of the results for step training and rehabilitation after injury are discussed.
Regularities of Multifractal Measures
Hun Ki Baek
2008-05-01
First, we prove the decomposition theorem for the regularities of multifractal Hausdorff measure and packing measure in $\\mathbb{R}^d$. This decomposition theorem enables us to split a set into regular and irregular parts, so that we can analyze each separately, and recombine them without affecting density properties. Next, we give some properties related to multifractal Hausdorff and packing densities. Finally, we extend the density theorem in [6] to any measurable set.
Regularized Structural Equation Modeling.
Jacobucci, Ross; Grimm, Kevin J; McArdle, John J
A new method is proposed that extends the use of regularization in both lasso and ridge regression to structural equation models. The method is termed regularized structural equation modeling (RegSEM). RegSEM penalizes specific parameters in structural equation models, with the goal of creating easier to understand and simpler models. Although regularization has gained wide adoption in regression, very little has transferred to models with latent variables. By adding penalties to specific parameters in a structural equation model, researchers have a high level of flexibility in reducing model complexity, overcoming poor fitting models, and the creation of models that are more likely to generalize to new samples. The proposed method was evaluated through a simulation study, two illustrative examples involving a measurement model, and one empirical example involving the structural part of the model to demonstrate RegSEM's utility.
Faupin, Jeremy; Møller, Jacob Schach; Skibsted, Erik
2011-01-01
We study regularity of bound states pertaining to embedded eigenvalues of a self-adjoint operator H, with respect to an auxiliary operator A that is conjugate to H in the sense of Mourre. We work within the framework of singular Mourre theory which enables us to deal with confined massless Pauli–......–Fierz models, our primary example, and many-body AC-Stark Hamiltonians. In the simpler context of regular Mourre theory, our results boil down to an improvement of results obtained recently in [8, 9]....
Annotation of Regular Polysemy
Martinez Alonso, Hector
Regular polysemy has received a lot of attention from the theory of lexical semantics and from computational linguistics. However, there is no consensus on how to represent the sense of underspecified examples at the token level, namely when annotating or disambiguating senses of metonymic words...
On the regularity in some variational problems
Ragusa, Maria Alessandra; Tachikawa, Atsushi
2017-01-01
Our main goal is the study some regularity results where are considered estimates in Morrey spaces for the derivatives of local minimizers of variational integrals of the form 𝒜 (u ,Ω )= ∫Ω F (x ,u ,D u ) dx where Ω is a bounded domain in ℝm and the integrand F have some different forms.
Sparse structure regularized ranking
Wang, Jim Jing-Yan
2014-04-17
Learning ranking scores is critical for the multimedia database retrieval problem. In this paper, we propose a novel ranking score learning algorithm by exploring the sparse structure and using it to regularize ranking scores. To explore the sparse structure, we assume that each multimedia object could be represented as a sparse linear combination of all other objects, and combination coefficients are regarded as a similarity measure between objects and used to regularize their ranking scores. Moreover, we propose to learn the sparse combination coefficients and the ranking scores simultaneously. A unified objective function is constructed with regard to both the combination coefficients and the ranking scores, and is optimized by an iterative algorithm. Experiments on two multimedia database retrieval data sets demonstrate the significant improvements of the propose algorithm over state-of-the-art ranking score learning algorithms.
Regularized Reduced Order Models
Wells, David; Xie, Xuping; Iliescu, Traian
2015-01-01
This paper puts forth a regularization approach for the stabilization of proper orthogonal decomposition (POD) reduced order models (ROMs) for the numerical simulation of realistic flows. Two regularized ROMs (Reg-ROMs) are proposed: the Leray ROM (L-ROM) and the evolve-then-filter ROM (EF-ROM). These new Reg-ROMs use spatial filtering to smooth (regularize) various terms in the ROMs. Two spatial filters are used: a POD projection onto a POD subspace (Proj) and a new POD differential filter (DF). The four Reg-ROM/filter combinations are tested in the numerical simulation of the one-dimensional Burgers equation with a small diffusion coefficient and the three-dimensional flow past a circular cylinder at a low Reynolds number (Re = 100). Overall, the most accurate Reg-ROM/filter combination is EF-ROM-DF. Furthermore, the DF generally yields better results than Proj. Finally, the four Reg-ROM/filter combinations are computationally efficient and generally more accurate than the standard Galerkin ROM.
Regularizing portfolio optimization
Still, Susanne; Kondor, Imre
2010-07-01
The optimization of large portfolios displays an inherent instability due to estimation error. This poses a fundamental problem, because solutions that are not stable under sample fluctuations may look optimal for a given sample, but are, in effect, very far from optimal with respect to the average risk. In this paper, we approach the problem from the point of view of statistical learning theory. The occurrence of the instability is intimately related to over-fitting, which can be avoided using known regularization methods. We show how regularized portfolio optimization with the expected shortfall as a risk measure is related to support vector regression. The budget constraint dictates a modification. We present the resulting optimization problem and discuss the solution. The L2 norm of the weight vector is used as a regularizer, which corresponds to a diversification 'pressure'. This means that diversification, besides counteracting downward fluctuations in some assets by upward fluctuations in others, is also crucial because it improves the stability of the solution. The approach we provide here allows for the simultaneous treatment of optimization and diversification in one framework that enables the investor to trade off between the two, depending on the size of the available dataset.
Wen LIU; Jing LIN
2011-01-01
In this paper,we define a class of strongly connected digraph,called the k-walk-regular digraph,study some properties of it,provide its some algebraic characterization and point out that the O-walk-regular digraph is the same as the walk-regular digraph discussed BY Liu and Lin in 2010 and the D-walk-regular digraph is identical with the weakly distance-regular digraph defined by Comellas et al in 2004.
2009-03-30
These observations will be compared with raytracing models. These analyses will determine the controlling factors of the coupling between the...ionosphere and magnetosphere, and the propagation characteristics of whistler waves in space, verify the raytracing models, and provide guidance for... raytracing model improvements when necessary. Correctly modeling whistler wave propagation in the magnetosphere as functions of plasma conditions and wave
Modeling polycrystals with regular polyhedra
Paulo Rangel Rios
2006-06-01
Full Text Available Polycrystalline structure is of paramount importance to materials science and engineering. It provides an important example of a space-filling irregular network structure that also occurs in foams as well as in certain biological tissues. Therefore, seeking an accurate description of the characteristics of polycrystals is of fundamental importance. Recently, one of the authors (MEG published a paper in which a method was devised of representation of irregular networks by regular polyhedra with curved faces. In Glicksman's method a whole class of irregular polyhedra with a given number of faces, N, is represented by a single symmetrical polyhedron with N curved faces. This paper briefly describes the topological and metric properties of these special polyhedra. They are then applied to two important problems of irregular networks: the dimensionless energy 'cost' of irregular networks, and the derivation of a 3D analogue of the von Neumann-Mullins equation for the growth rate of grains in a polycrystal.
Leng, Yunxia; Lan, Weizhong; Yu, Keming; Liu, Bingqian; Yang, Zhikuan; Li, Zheng; Zhong, Xingwu; Zhang, Shaochong; Ge, Jian
2010-12-01
This study aimed to investigate the effects of sustained near vision stimulation, on the refractive development and elongation of the vitreous chamber in adolescent rhesus monkeys. A total of 12 adolescent rhesus monkeys (1.5-2.0 years old) were randomly assigned to 3 groups. In groups A (n=4) and B (n=4), monkeys were reared in close-vision cages for 8 and 4 h d(-1), respectively; tiny granules were added on the cage floor to avoid visual deprivation and to encourage near gaze. In group C (n=4), monkeys were reared in open-vision cages, with non-granule food as a control. Vitreous chamber depth, refractive status, and corneal refractive power were assessed over 18 months. Paired t-test was used to compare the differences and a P-valuemonkeys. Our results demonstrate the potential for a primate model of near-work-related myopia.
Annotation of Regular Polysemy
Martinez Alonso, Hector
Regular polysemy has received a lot of attention from the theory of lexical semantics and from computational linguistics. However, there is no consensus on how to represent the sense of underspecified examples at the token level, namely when annotating or disambiguating senses of metonymic words...... like “London” (Location/Organization) or “cup” (Container/Content). The goal of this dissertation is to assess whether metonymic sense underspecification justifies incorporating a third sense into our sense inventories, thereby treating the underspecified sense as independent from the literal...
Learning Rates for -Regularized Kernel Classifiers
Hongzhi Tong
2013-01-01
Full Text Available We consider a family of classification algorithms generated from a regularization kernel scheme associated with -regularizer and convex loss function. Our main purpose is to provide an explicit convergence rate for the excess misclassification error of the produced classifiers. The error decomposition includes approximation error, hypothesis error, and sample error. We apply some novel techniques to estimate the hypothesis error and sample error. Learning rates are eventually derived under some assumptions on the kernel, the input space, the marginal distribution, and the approximation error.
From regular modules to von Neumann regular rings via coordinatization
Leonard Daus
2014-07-01
Full Text Available In this paper we establish a very close link (in terms of von Neu- mann's coordinatization between regular modules introduced by Zel- manowitz, on one hand, and von Neumann regular rings, on the other hand: we prove that the lattice L^{fg}(M of all finitely generated submodules of a finitely generated regular module M, over an arbitrary ring, can be coordinatized as the lattice of all principal right ideals of some von Neumann regular ring S.
Modular Regularization Algorithms
Jacobsen, Michael
2004-01-01
The class of linear ill-posed problems is introduced along with a range of standard numerical tools and basic concepts from linear algebra, statistics and optimization. Known algorithms for solving linear inverse ill-posed problems are analyzed to determine how they can be decomposed into indepen......The class of linear ill-posed problems is introduced along with a range of standard numerical tools and basic concepts from linear algebra, statistics and optimization. Known algorithms for solving linear inverse ill-posed problems are analyzed to determine how they can be decomposed...... into independent modules. These modules are then combined to form new regularization algorithms with other properties than those we started out with. Several variations are tested using the Matlab toolbox MOORe Tools created in connection with this thesis. Object oriented programming techniques are explained...... and used to set up the illposed problems in the toolbox. Hereby, we are able to write regularization algorithms that automatically exploit structure in the ill-posed problem without being rewritten explicitly. We explain how to implement a stopping criteria for a parameter choice method based upon...
Structure for Regular Inclusions
Pitts, David R
2012-01-01
We study pairs (C,D) of unital C*-algebras where D is an abelian C*-subalgebra of C which is regular in C. When D is a MASA in C, there exists a unique completely positive unital map E of C into the injective envelope I(D) of D whose restriction to D is the identity on D. We show that the left kernel of E is the unique closed two-sided ideal of C maximal with respect to having trivial intersection with D. We introduce a new class of well behaved state extensions, the compatible states; we identify compatible states when D is a MASA in C in terms of groups constructed from local dynamics near a pure state on D. When C is separable, D is a MASA in C, and the pair (C,D) is regular, the set of pure states on D with unique state extensions to C is dense in D. The map E can be used as a substitute for a conditional expectation in the construction of coordinates for C relative to D. We show that certain classes of compatible states have natural groupoid operations, and we show that constructions of Kumjian and Renau...
Raitt, W. J.; Banks, P. M.; Denig, W. F.; Anderson, H. R.
1982-01-01
Interest in the interaction of electron beams with plasma generated by ionization caused by the primary electron beam was stimulated by the need to develop special vacuum tubes to operate in the kMHz frequency region. The experiments of Getty and Smullin (1963) indicated that the interaction of an energetic electron beam with its self-produced plasma resulted in the emission of wave energy over a wide range of frequencies associated with cyclotron and longitudinal plasma instabilities. This enhanced the thermal plasma density in the vicinity of the beam, and the term Beam-Plasma Discharge (BPD) was employed to described this phenomenon. The present investigation is concerned with some of the transient phenomena associated with wave emission during the beam switch-on and switch-off periods. Results are presented on the changes in electron energy spectra on a time scale of tens of milliseconds following beam switch-on. The results are discussed in terms of the beam plasma discharge phenomenon.
Shijun eLi
2015-07-01
Full Text Available Background and objective: The relationship between EEG source signals and action-related visual and auditory stimulation is still not well understood. The objective of this study was to identify EEG source signals and their associated action-related visual and auditory responses, especially independent components of EEG.Methods: A hand-moving-Hanoi video paradigm was used to study neural correlates of the action-related visual and auditory information processing determined by mu rhythm (8-12 Hz in 16 healthy young subjects. Independent component analysis (ICA was applied to identify separate EEG sources, and further computed in the frequency domain by applying-Fourier transform ICA (F-ICA.Results: F-ICA found more sensory stimuli-related independent components located within the sensorimotor region than ICA did. The total number of independent components of interest from F-ICA was 768, twice that of 384 from traditional time-domain ICA (p0.05.Conclusions: These results support the hypothesis that mu rhythm was sensitive to detection of the cognitive expression, which could be reflected by the function in the parietal lobe sensory-motor region. The results of this study could potentially be applied into early diagnosis for those with visual and hearing impairments in the future.
Learning rates of lq coefficient regularization learning with gaussian kernel.
Lin, Shaobo; Zeng, Jinshan; Fang, Jian; Xu, Zongben
2014-10-01
Regularization is a well-recognized powerful strategy to improve the performance of a learning machine and l(q) regularization schemes with 0 regularization leads to a smooth estimator, while l(1) regularization leads to a sparse estimator. Then how the generalization capability of l(q) regularization learning varies with q is worthy of investigation. In this letter, we study this problem in the framework of statistical learning theory. Our main results show that implementing l(q) coefficient regularization schemes in the sample-dependent hypothesis space associated with a gaussian kernel can attain the same almost optimal learning rates for all 0 regularization learning are asymptotically identical for all 0 < q < ∞. Our finding tentatively reveals that in some modeling contexts, the choice of q might not have a strong impact on the generalization capability. From this perspective, q can be arbitrarily specified, or specified merely by other nongeneralization criteria like smoothness, computational complexity or sparsity.
Obregón, O; Ryan, M P; Obregon, Octavio; Quevedo, Hernando; Ryan, Michael P.
2004-01-01
We construct a family of time and angular dependent, regular S-brane solutions which corresponds to a simple analytical continuation of the Zipoy-Voorhees 4-dimensional vacuum spacetime. The solutions are asymptotically flat and turn out to be free of singularities without requiring a twist in space. They can be considered as the simplest non-singular generalization of the singular S0-brane solution. We analyze the properties of a representative of this family of solutions and show that it resembles to some extent the asymptotic properties of the regular Kerr S-brane. The R-symmetry corresponds, however, to the general Lorentzian symmetry. Several generalizations of this regular solution are derived which include a charged S-brane and an additional dilatonic field.
无
2010-01-01
This study aimed to investigate the effects of sustained near vision stimulation,on the refractive development and elongation of the vitreous chamber in adolescent rhesus monkeys.A total of 12 adolescent rhesus monkeys(1.5-2.0 years old) were randomly assigned to 3 groups.In groups A(n=4) and B(n=4),monkeys were reared in close-vision cages for 8 and 4 h d-1,respectively;tiny granules were added on the cage floor to avoid visual deprivation and to encourage near gaze.In group C(n=4),monkeys were reared in open-vision cages,with non-granule food as a control.Vitreous chamber depth,refractive status,and corneal refractive power were assessed over 18 months.Paired t-test was used to compare the differences and a P-value<0.05 was considered to be statistically significant.In group A,vitreous chamber depth and optical axis elongated significantly,and refractive error shifted towards myopia during the observation period.In group B,vitreous chambers and optical axis elongated but the refractive power did not show significant changes.In group C,there was no significant elongation in vitreous chambers and optical axis,and the refractive power changed slightly towards hypermetropia.There were no significant changes in corneal refractive power in each group.Sustained near vision can promote vitreous chamber growth and induce myopic shifts in refractive power in adolescent monkeys.Our results demonstrate the potential for a primate model of near-work-related myopia.
Evolutionary internalized regularities.
Schwartz, R
2001-08-01
Roger Shepard's proposals and supporting experiments concerning evolutionary internalized regularities have been very influential in the study of vision and in other areas of psychology and cognitive science. This paper examines issues concerning the need, nature, explanatory role, and justification for postulating such internalized constraints. In particular, I seek further clarification from Shepard on how best to understand his claim that principles of kinematic geometry underlie phenomena of motion perception. My primary focus is on the ecological validity of Shepard's kinematic constraint in the context of ordinary motion perception. First, I explore the analogy Shepard draws between internalized circadian rhythms and the supposed internalization of kinematic geometry. Next, questions are raised about how to interpret and justify applying results from his own and others' experimental studies of apparent motion to more everyday cases of motion perception in richer environments. Finally, some difficulties with Shepard's account of the evolutionary development of his kinematic constraint are considered.
Adaptive Regularization of Neural Classifiers
Andersen, Lars Nonboe; Larsen, Jan; Hansen, Lars Kai
1997-01-01
We present a regularization scheme which iteratively adapts the regularization parameters by minimizing the validation error. It is suggested to use the adaptive regularization scheme in conjunction with optimal brain damage pruning to optimize the architecture and to avoid overfitting. Furthermo...
Mining High Utility Itemsets with Regular Occurrence
Komate Amphawan
2016-09-01
Full Text Available High utility itemset mining (HUIM plays an important role in the data mining community and in a wide range of applications. For example, in retail business it is used for finding sets of sold products that give high profit, low cost, etc. These itemsets can help improve marketing strategies, make promotions/ advertisements, etc. However, since HUIM only considers utility values of items/itemsets, it may not be sufficient to observe product-buying behavior of customers such as information related to “regular purchases of sets of products having a high profit margin”. To address this issue, the occurrence behavior of itemsets (in the term of regularity simultaneously with their utility values was investigated. Then, the problem of mining high utility itemsets with regular occurrence (MHUIR to find sets of co-occurrence items with high utility values and regular occurrence in a database was considered. An efficient single-pass algorithm, called MHUIRA, was introduced. A new modified utility-list structure, called NUL, was designed to efficiently maintain utility values and occurrence information and to increase the efficiency of computing the utility of itemsets. Experimental studies on real and synthetic datasets and complexity analyses are provided to show the efficiency of MHUIRA combined with NUL in terms of time and space usage for mining interesting itemsets based on regularity and utility constraints.
Dimensional regularization and renormalization of non-commutative QFT
Gurau, R
2007-01-01
Using the recently introduced parametric representation of non-commutative quantum field theory, we implement here the dimensional regularization and renormalization of the vulcanized $\\Phi^{\\star 4}_4$ model on the Moyal space.
Maziar Nekovee
2010-01-01
Full Text Available Cognitive radio is being intensively researched as the enabling technology for license-exempt access to the so-called TV White Spaces (TVWS, large portions of spectrum in the UHF/VHF bands which become available on a geographical basis after digital switchover. Both in the US, and more recently, in the UK the regulators have given conditional endorsement to this new mode of access. This paper reviews the state-of-the-art in technology, regulation, and standardisation of cognitive access to TVWS. It examines the spectrum opportunity and commercial use cases associated with this form of secondary access.
Regularity of weak solutions to the Landau-Lifshitz system in bounded regular domains
Kevin Santugini-Repiquet
2007-10-01
Full Text Available In this paper, we study the regularity, on the boundary, of weak solutions to the Landau-Lifshitz system in the framework of the micromagnetic model in the quasi-static approximation. We establish the existence of global weak solutions to the Landau-Lifshitz system whose tangential space gradient on the boundary is square integrable.
Regular black hole in three dimensions
Myung, Yun Soo; Yoon, Myungseok
2008-01-01
We find a new black hole in three dimensional anti-de Sitter space by introducing an anisotropic perfect fluid inspired by the noncommutative black hole. This is a regular black hole with two horizons. We compare thermodynamics of this black hole with that of non-rotating BTZ black hole. The first-law of thermodynamics is not compatible with the Bekenstein-Hawking entropy.
Regular black hole in three dimensions
Myung, Yun Soo; Yoon, Myungseok
2008-01-01
We find a new black hole in three dimensional anti-de Sitter space by introducing an anisotropic perfect fluid inspired by the noncommutative black hole. This is a regular black hole with two horizons. We compare thermodynamics of this black hole with that of non-rotating BTZ black hole. The first-law of thermodynamics is not compatible with the Bekenstein-Hawking entropy.
Bambi, Cosimo
2013-01-01
The formation of spacetime singularities is a quite common phenomenon in General Relativity and it is regulated by specific theorems. It is widely believed that spacetime singularities do not exist in Nature, but that they represent a limitation of the classical theory. While we do not yet have any solid theory of quantum gravity, toy models of black hole solutions without singularities have been proposed. So far, there are only non-rotating regular black holes in the literature. These metrics can be hardly tested by astrophysical observations, as the black hole spin plays a fundamental role in any astrophysical process. In this letter, we apply the Newman-Janis algorithm to the Hayward and to the Bardeen black hole metrics. In both cases, we obtain a family of rotating solutions. Every solution corresponds to a different matter configuration. Each family has one solution with special properties, which can be written in Kerr-like form in Boyer-Lindquist coordinates. These special solutions are of Petrov type ...
Bambi, Cosimo, E-mail: bambi@fudan.edu.cn; Modesto, Leonardo, E-mail: lmodesto@fudan.edu.cn
2013-04-25
The formation of spacetime singularities is a quite common phenomenon in General Relativity and it is regulated by specific theorems. It is widely believed that spacetime singularities do not exist in Nature, but that they represent a limitation of the classical theory. While we do not yet have any solid theory of quantum gravity, toy models of black hole solutions without singularities have been proposed. So far, there are only non-rotating regular black holes in the literature. These metrics can be hardly tested by astrophysical observations, as the black hole spin plays a fundamental role in any astrophysical process. In this Letter, we apply the Newman–Janis algorithm to the Hayward and to the Bardeen black hole metrics. In both cases, we obtain a family of rotating solutions. Every solution corresponds to a different matter configuration. Each family has one solution with special properties, which can be written in Kerr-like form in Boyer–Lindquist coordinates. These special solutions are of Petrov type D, they are singularity free, but they violate the weak energy condition for a non-vanishing spin and their curvature invariants have different values at r=0 depending on the way one approaches the origin. We propose a natural prescription to have rotating solutions with a minimal violation of the weak energy condition and without the questionable property of the curvature invariants at the origin.
Construction of Regular Black Holes in General Relativity
Fan, Zhong-Ying
2016-01-01
We present a general procedure for constructing exact black hole solutions with electric/magnetic charges in General Relativity coupled to a nonlinear electrodynamics. We obtain a variety of two-parameter family spherically symmetric black hole solutions. In particular, the singularity at the central of the space-time can be cancelled in the parameters space and the black hole solutions become regular everywhere in the space-time. We study the global properties of the solutions and derive the first law of thermodynamics. We also generalize the procedure to include a cosmological constant and construct regular black hole solutions that are asymptotic to anti-de Sitter space-time.
Construction of regular black holes in general relativity
Fan, Zhong-Ying; Wang, Xiaobao
2016-12-01
We present a general procedure for constructing exact black hole solutions with electric or magnetic charges in general relativity coupled to a nonlinear electrodynamics. We obtain a variety of two-parameter family spherically symmetric black hole solutions. In particular, the singularity at the center of the space-time can be canceled in the parameter space and the black hole solutions become regular everywhere in space-time. We study the global properties of the solutions and derive the first law of thermodynamics. We also generalize the procedure to include a cosmological constant and construct regular black hole solutions that are asymptotic to anti-de Sitter space-time.
Regularity for solutions of non local parabolic equations
Lara, Héctor A Chang
2011-01-01
We study the regularity of solutions of parabolic fully nonlinear nonlocal equations. We proof $C^\\a$ regularity in space and time and for translation invariant equations and under different assumptions on the kernels $C^{1,\\a}$ in space and time regularity. The proofs rely on a weak parabolic ABP inspired in recent work done by L. Silvestre and the classic ideas of K. Tso and L. Wang. Our results remain uniform as $\\s\\to2$ allowing us to understand the non local theory as an extension to the classical one.
Generalization Performance of Regularized Ranking With Multiscale Kernels.
Zhou, Yicong; Chen, Hong; Lan, Rushi; Pan, Zhibin
2016-05-01
The regularized kernel method for the ranking problem has attracted increasing attentions in machine learning. The previous regularized ranking algorithms are usually based on reproducing kernel Hilbert spaces with a single kernel. In this paper, we go beyond this framework by investigating the generalization performance of the regularized ranking with multiscale kernels. A novel ranking algorithm with multiscale kernels is proposed and its representer theorem is proved. We establish the upper bound of the generalization error in terms of the complexity of hypothesis spaces. It shows that the multiscale ranking algorithm can achieve satisfactory learning rates under mild conditions. Experiments demonstrate the effectiveness of the proposed method for drug discovery and recommendation tasks.
Regular Bisimple ω2-semigroups
汪立民; 商宇
2008-01-01
@@ The regular semigroups S with an idempotent set Es = {e0,e1,…,en,…} such that e0 ＞ e1 ＞…＞ en ＞… is called a regular ω-semigroup. In [5] Reilly determined the structure of a regular bisimple ω-semigroup as BR(G,θ),which is the classical Bruck-Reilly extension of a group G.
On regular rotating black holes
Torres, R.; Fayos, F.
2017-01-01
Different proposals for regular rotating black hole spacetimes have appeared recently in the literature. However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking. In this note we analyze rotating Kerr-like black hole spacetimes and find the necessary and sufficient conditions for the regularity of all their second order scalar invariants polynomial in the Riemann tensor. We also show that the regularity is linked to a violation of the weak energy conditions around the core of the rotating black hole.
On regular rotating black holes
Torres, Ramon
2016-01-01
Different proposals for regular rotating black hole spacetimes have appeared recently in the literature. However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking. In this note we analyze rotating Kerr-like black hole spacetimes and find the necessary and sufficient conditions for the regularity of all their second order scalar invariants polynomial in the Riemann tensor. We also show that the regularity is linked to a violation of the weak energy conditions around the core of the rotating black hole.
CHEN Huan Yin; LI Fu An
2002-01-01
In this paper, we investigate ideals of regular rings and give several characterizations for an ideal to satisfy the comparability. In addition, it is shown that, if Ⅰ is a minimal two-sided ideal of a regular ring R, then Ⅰ satisfies the comparability if and only if Ⅰ is separative. Furthermore, we prove that, for ideals with stable range one, Roth's problem has an affirmative solution. These extend the corresponding results on unit-regularity and one-sided unit-regularity.
Regularly timed events amid chaos
Blakely, Jonathan N.; Cooper, Roy M.; Corron, Ned J.
2015-11-01
We show rigorously that the solutions of a class of chaotic oscillators are characterized by regularly timed events in which the derivative of the solution is instantaneously zero. The perfect regularity of these events is in stark contrast with the well-known unpredictability of chaos. We explore some consequences of these regularly timed events through experiments using chaotic electronic circuits. First, we show that a feedback loop can be implemented to phase lock the regularly timed events to a periodic external signal. In this arrangement the external signal regulates the timing of the chaotic signal but does not strictly lock its phase. That is, phase slips of the chaotic oscillation persist without disturbing timing of the regular events. Second, we couple the regularly timed events of one chaotic oscillator to those of another. A state of synchronization is observed where the oscillators exhibit synchronized regular events while their chaotic amplitudes and phases evolve independently. Finally, we add additional coupling to synchronize the amplitudes, as well, however in the opposite direction illustrating the independence of the amplitudes from the regularly timed events.
Online co-regularized algorithms
Ruijter, T. de; Tsivtsivadze, E.; Heskes, T.
2012-01-01
We propose an online co-regularized learning algorithm for classification and regression tasks. We demonstrate that by sequentially co-regularizing prediction functions on unlabeled data points, our algorithm provides improved performance in comparison to supervised methods on several UCI benchmarks
Online co-regularized algorithms
Ruijter, T. de; Tsivtsivadze, E.; Heskes, T.
2012-01-01
We propose an online co-regularized learning algorithm for classification and regression tasks. We demonstrate that by sequentially co-regularizing prediction functions on unlabeled data points, our algorithm provides improved performance in comparison to supervised methods on several UCI benchmarks
Nonconvex Regularization in Remote Sensing
Tuia, Devis; Flamary, Remi; Barlaud, Michel
2016-11-01
In this paper, we study the effect of different regularizers and their implications in high dimensional image classification and sparse linear unmixing. Although kernelization or sparse methods are globally accepted solutions for processing data in high dimensions, we present here a study on the impact of the form of regularization used and its parametrization. We consider regularization via traditional squared (2) and sparsity-promoting (1) norms, as well as more unconventional nonconvex regularizers (p and Log Sum Penalty). We compare their properties and advantages on several classification and linear unmixing tasks and provide advices on the choice of the best regularizer for the problem at hand. Finally, we also provide a fully functional toolbox for the community.
Conservative regularization of compressible flow
Krishnaswami, Govind S; Thyagaraja, Anantanarayanan
2015-01-01
Ideal Eulerian flow may develop singularities in vorticity w. Navier-Stokes viscosity provides a dissipative regularization. We find a local, conservative regularization - lambda^2 w times curl(w) of compressible flow and compressible MHD: a three dimensional analogue of the KdV regularization of the one dimensional kinematic wave equation. The regulator lambda is a field subject to the constitutive relation lambda^2 rho = constant. Lambda is like a position-dependent mean-free path. Our regularization preserves Galilean, parity and time-reversal symmetries. We identify locally conserved energy, helicity, linear and angular momenta and boundary conditions ensuring their global conservation. Enstrophy is shown to remain bounded. A swirl velocity field is identified, which transports w/rho and B/rho generalizing the Kelvin-Helmholtz and Alfven theorems. A Hamiltonian and Poisson bracket formulation is given. The regularized equations are used to model a rotating vortex, channel flow, plane flow, a plane vortex ...
Approximate Sparse Regularized Hyperspectral Unmixing
Chengzhi Deng
2014-01-01
Full Text Available Sparse regression based unmixing has been recently proposed to estimate the abundance of materials present in hyperspectral image pixel. In this paper, a novel sparse unmixing optimization model based on approximate sparsity, namely, approximate sparse unmixing (ASU, is firstly proposed to perform the unmixing task for hyperspectral remote sensing imagery. And then, a variable splitting and augmented Lagrangian algorithm is introduced to tackle the optimization problem. In ASU, approximate sparsity is used as a regularizer for sparse unmixing, which is sparser than l1 regularizer and much easier to be solved than l0 regularizer. Three simulated and one real hyperspectral images were used to evaluate the performance of the proposed algorithm in comparison to l1 regularizer. Experimental results demonstrate that the proposed algorithm is more effective and accurate for hyperspectral unmixing than state-of-the-art l1 regularizer.
ZOU Zhi-Yun; MAO Bao-Hua; HAO Hai-Ming; GAO Jian-Zhi; YANG Jie-Jiao
2009-01-01
According to the deficiencies in Watts and Strogatz's small-world network model, we present a new regular model to establish the small-world network. Besides the property of the small-world, this model has other properties such as accuracy in controlling the average shortest path length L, and the average clustering coefficient C, also regular network topology as well as enhanced network robustness. This method improves the construction of the small-world network essentially, so that the regular small-world network closely resembles the actual network. We also present studies on the relationships among the quantities of a variety of edges, L and C in regular small-world network in detail. This research lays the foundation for the establishment of the regular small-world network and acts as a good guidance for further research of this model and its applications.
Half-Cell Law of Regular Cellular Detonations
WANG Chun; JIANG Zong-Lin; GAO Yun-Liang
2008-01-01
Numerical simulations illustrate the half-cell law of regular cellular detonations propagating in confined space,i.e., the number of cells always maintains an integral multiple of half cell. The cells adapt themselves larger or smaller to the size of the unconfined space by maintaining the cell scale larger or smaller than the original cells of detonation.
Extreme values, regular variation and point processes
Resnick, Sidney I
1987-01-01
Extremes Values, Regular Variation and Point Processes is a readable and efficient account of the fundamental mathematical and stochastic process techniques needed to study the behavior of extreme values of phenomena based on independent and identically distributed random variables and vectors It presents a coherent treatment of the distributional and sample path fundamental properties of extremes and records It emphasizes the core primacy of three topics necessary for understanding extremes the analytical theory of regularly varying functions; the probabilistic theory of point processes and random measures; and the link to asymptotic distribution approximations provided by the theory of weak convergence of probability measures in metric spaces The book is self-contained and requires an introductory measure-theoretic course in probability as a prerequisite Almost all sections have an extensive list of exercises which extend developments in the text, offer alternate approaches, test mastery and provide for enj...
Chiral Perturbation Theory With Lattice Regularization
Ouimet, P P A
2005-01-01
In this work, alternative methods to regularize chiral perturbation theory are discussed. First, Long Distance Regularization will be considered in the presence of the decuplet of the lightest spin 32 baryons for several different observables. This serves motivation and introduction to the use of the lattice regulator for chiral perturbation theory. The mesonic, baryonic and anomalous sectors of chiral perturbation theory will be formulated on a lattice of space time points. The consistency of the lattice as a regulator will be discussed in the context of the meson and baryon masses. Order a effects will also be discussed for the baryon masses, sigma terms and magnetic moments. The work will close with an attempt to derive an effective Wess-Zumino-Witten Lagrangian for Wilson fermions at non-zero a. Following this discussion, there will be a proposal for a phenomenologically useful WZW Lagrangian at non-zero a.
Effort variation regularization in sound field reproduction
Stefanakis, Nick; Jacobsen, Finn; Sarris, Ioannis
2010-01-01
. Specifically, it is suggested that the phase differential of the source driving signals should be in agreement with the phase differential of the desired sound pressure field. The performance of the suggested method is compared with that of conventional effort regularization, wave field synthesis (WFS......In this paper, active control is used in order to reproduce a given sound field in an extended spatial region. A method is proposed which minimizes the reproduction error at a number of control positions with the reproduction sources holding a certain relation within their complex strengths......), and adaptive wave field synthesis (AWFS), both under free-field conditions and in reverberant rooms. It is shown that effort variation regularization overcomes the problems associated with small spaces and with a low ratio of direct to reverberant energy, improving thus the reproduction accuracy...
A Criterion for Regular Sequences
D P Patil; U Storch; J Stückrad
2004-05-01
Let be a commutative noetherian ring and $f_1,\\ldots,f_r \\in R$. In this article we give (cf. the Theorem in $\\mathcal{x}$2) a criterion for $f_1,\\ldots,f_r$ to be regular sequence for a finitely generated module over which strengthens and generalises a result in [2]. As an immediate consequence we deduce that if $V(g_1,\\ldots,g_r) \\subseteq V(f_1,\\ldots,f_r)$ in Spec and if $f_1,\\ldots,f_r$ is a regular sequence in , then $g_1,\\ldots,g_r$ is also a regular sequence in .
Naoto Shiba
Full Text Available Musculoskeletal atrophy is one of the major problems of extended periods of exposure to weightlessness such as on the International Space Station (ISS. We developed the Hybrid Training System (HTS to maintain an astronaut's musculoskeletal system using an electrically stimulated antagonist to resist the volitional contraction of the agonist instead of gravity. The present study assessed the system's orbital operation capability and utility, as well as its preventative effect on an astronaut's musculoskeletal atrophy.HTS was attached to the non-dominant arm of an astronaut staying on the ISS, and his dominant arm without HTS was established as the control (CTR. 10 sets of 10 reciprocal elbow curls were one training session, and 12 total sessions of training (3 times per week for 4 weeks were performed. Pre and post flight ground based evaluations were performed by Biodex (muscle performance, MRI (muscle volume, and DXA (BMD, lean [muscle] mass, fat mass. Pre and post training inflight evaluations were performed by a hand held dynamometer (muscle force and a measuring tape (upper arm circumference.The experiment was completed on schedule, and HTS functioned well without problems. Isokinetic elbow extension torque (Nm changed -19.4% in HTS, and -21.7% in CTR. Isokinetic elbow flexion torque changed -23.7% in HTS, and there was no change in CTR. Total Work (Joule of elbow extension changed -8.3% in HTS, and +0.3% in CTR. For elbow flexion it changed -23.3% in HTS and -32.6% in CTR. Average Power (Watts of elbow extension changed +22.1% in HTS and -8.0% in CTR. For elbow flexion it changed -6.5% in HTS and -4.8% in CTR. Triceps muscle volume according to MRI changed +11.7% and that of biceps was +2.1% using HTS, however -0.1% and -0.4% respectively for CTR. BMD changed +4.6% in the HTS arm and -1.2% for CTR. Lean (muscle mass of the arm changed only +10.6% in HTS. Fat mass changed -12.6% in HTS and -6.4% in CTR.These results showed the orbital
Shiba, Naoto; Matsuse, Hiroo; Takano, Yoshio; Yoshimitsu, Kazuhiro; Omoto, Masayuki; Hashida, Ryuki; Tagawa, Yoshihiko; Inada, Tomohisa; Yamada, Shin; Ohshima, Hiroshi
2015-01-01
Musculoskeletal atrophy is one of the major problems of extended periods of exposure to weightlessness such as on the International Space Station (ISS). We developed the Hybrid Training System (HTS) to maintain an astronaut's musculoskeletal system using an electrically stimulated antagonist to resist the volitional contraction of the agonist instead of gravity. The present study assessed the system's orbital operation capability and utility, as well as its preventative effect on an astronaut's musculoskeletal atrophy. HTS was attached to the non-dominant arm of an astronaut staying on the ISS, and his dominant arm without HTS was established as the control (CTR). 10 sets of 10 reciprocal elbow curls were one training session, and 12 total sessions of training (3 times per week for 4 weeks) were performed. Pre and post flight ground based evaluations were performed by Biodex (muscle performance), MRI (muscle volume), and DXA (BMD, lean [muscle] mass, fat mass). Pre and post training inflight evaluations were performed by a hand held dynamometer (muscle force) and a measuring tape (upper arm circumference). The experiment was completed on schedule, and HTS functioned well without problems. Isokinetic elbow extension torque (Nm) changed -19.4% in HTS, and -21.7% in CTR. Isokinetic elbow flexion torque changed -23.7% in HTS, and there was no change in CTR. Total Work (Joule) of elbow extension changed -8.3% in HTS, and +0.3% in CTR. For elbow flexion it changed -23.3% in HTS and -32.6% in CTR. Average Power (Watts) of elbow extension changed +22.1% in HTS and -8.0% in CTR. For elbow flexion it changed -6.5% in HTS and -4.8% in CTR. Triceps muscle volume according to MRI changed +11.7% and that of biceps was +2.1% using HTS, however -0.1% and -0.4% respectively for CTR. BMD changed +4.6% in the HTS arm and -1.2% for CTR. Lean (muscle) mass of the arm changed only +10.6% in HTS. Fat mass changed -12.6% in HTS and -6.4% in CTR. These results showed the orbital operation
Chris Moore
2012-01-01
Here, Moore presents a year in review on space exploration programs. This 2012 NASA's strategy of stimulating the development of commercial capabilities to launch crew and cargo to the ISS began to pay off...
Huanyin CHEN
2009-01-01
The necessary and sufficient conditions under which a ring satisfies regular power-substitution are investigated. It is shown that a ring R satisfies regular power-substitution if and only if a(-～)b in R implies that there exist n ∈ N and a U ∈ GLn(R) such that aU =Ub if and only if for any regular x ∈ R there exist m,n ∈ N and U ∈ GLn(R) such that xmIn = xmUxm, where a(-～)b means that there exists x, y, z ∈ R such that a = ybx, b = xaz and x = xyx = xzx. It is proved that every directly finite simple ring satisfies regular power-substitution. Some applications for stably free R-modules are also obtained.
NONCONVEX REGULARIZATION FOR SHAPE PRESERVATION
CHARTRAND, RICK [Los Alamos National Laboratory
2007-01-16
The authors show that using a nonconvex penalty term to regularize image reconstruction can substantially improve the preservation of object shapes. The commonly-used total-variation regularization, {integral}|{del}u|, penalizes the length of the object edges. They show that {integral}|{del}u|{sup p}, 0 < p < 1, only penalizes edges of dimension at least 2-p, and thus finite-length edges not at all. We give numerical examples showing the resulting improvement in shape preservation.
Regularization with a pruning prior
Goutte, Cyril; Hansen, Lars Kai
1997-01-01
We investigate the use of a regularization priorthat we show has pruning properties. Analyses areconducted both using a Bayesian framework and withthe generalization method, on a simple toyproblem. Results are thoroughly compared withthose obtained with a traditional weight decay.......We investigate the use of a regularization priorthat we show has pruning properties. Analyses areconducted both using a Bayesian framework and withthe generalization method, on a simple toyproblem. Results are thoroughly compared withthose obtained with a traditional weight decay....
Regular and Periodic Tachyon Kinks
Bazeia, D.; Menezes, R.; Ramos, J. G.
2004-01-01
We search for regular tachyon kinks in an extended model, which includes the tachyon action recently proposed to describe the tachyon field. The extended model that we propose adds a new contribution to the tachyon action, and seems to enrich the present scenario for the tachyon field. We have found stable tachyon kinks of regular profile, which may appropriately lead to the singular kink found by Sen sometime ago. Also, under specific conditions we may find periodic array of kink-antikink co...
Shervin Sahebi
2014-05-01
Full Text Available $R$ is called commuting regular ring (resp. semigroupif for each $x,y\\in R$ there exists $a\\in R$ such that$xy=yxayx$. In this paper, we introduce the concept ofcommuting $\\pi$-regular rings (resp. semigroups andstudy various properties of them.
汤娟娟
2014-01-01
写字是小学语文教学的主要任务之一，是提高学生素质的基本要求，也是弘扬和传承民族文化的重要途径。《义务教育语文课程标准》指出：“写字教学要重视对学生写字姿势的指导。引导学生掌握基本的书写技能，养成良好的写字习惯。”写字不仅在一定程度上反映一个人的语文水平，而且从一个侧面反映出一个人的文化素养；写字不仅有利于巩固识字，也利于培养集中注意、做事耐心细致的习惯和审美能力。通过几年来的教学实践，对于低年级的写字教学有以下几方面的体会。%Writing is the main teaching task of elementary Chinese,and the important content in elementary Chinese teaching of lower grades,which is a key link of strong base for learning Chinese. While teaching,it should study deeply of Chinese Course Standard,grasp teaching target precisely and stimulate students’interesting in writing to master the regular of writing by lovely and interesting teaching designs,in order to reach the designated teaching target.
Finite Deformations of Conformal Field Theories Using Analytically Regularized Connections
von Gussich, Alexander; Sundell, Per
1996-01-01
We study some natural connections on spaces of conformal field theories using an analytical regularization method. The connections are based on marginal conformal field theory deformations. We show that the analytical regularization preserves conformal invariance and leads to integrability of the marginal deformations. The connections are shown to be flat and to generate well-defined finite parallel transport. These finite parallel transports yield formulations of the deformed theories in the...
Limit cycle walking on a regularized ground
Jacobs, Henry O
2012-01-01
The singular nature of contact problems, such as walking, makes them difficult to analyze mathematically. In this paper we will "regularize" the contact problem of walking by approximating the ground with a smooth repulsive potential energy and a smooth dissipative friction force. Using this model we are able to prove the existence of a limit cycle for a periodically perturbed system which consists of three masses connected by springs. In particular, this limit cycle exists in a symmetry reduced phase. In the unreduced phase space, the motion of the masses resembles walking.
Condition Number Regularized Covariance Estimation.
Won, Joong-Ho; Lim, Johan; Kim, Seung-Jean; Rajaratnam, Bala
2013-06-01
Estimation of high-dimensional covariance matrices is known to be a difficult problem, has many applications, and is of current interest to the larger statistics community. In many applications including so-called the "large p small n" setting, the estimate of the covariance matrix is required to be not only invertible, but also well-conditioned. Although many regularization schemes attempt to do this, none of them address the ill-conditioning problem directly. In this paper, we propose a maximum likelihood approach, with the direct goal of obtaining a well-conditioned estimator. No sparsity assumption on either the covariance matrix or its inverse are are imposed, thus making our procedure more widely applicable. We demonstrate that the proposed regularization scheme is computationally efficient, yields a type of Steinian shrinkage estimator, and has a natural Bayesian interpretation. We investigate the theoretical properties of the regularized covariance estimator comprehensively, including its regularization path, and proceed to develop an approach that adaptively determines the level of regularization that is required. Finally, we demonstrate the performance of the regularized estimator in decision-theoretic comparisons and in the financial portfolio optimization setting. The proposed approach has desirable properties, and can serve as a competitive procedure, especially when the sample size is small and when a well-conditioned estimator is required.
Condition Number Regularized Covariance Estimation*
Won, Joong-Ho; Lim, Johan; Kim, Seung-Jean; Rajaratnam, Bala
2012-01-01
Estimation of high-dimensional covariance matrices is known to be a difficult problem, has many applications, and is of current interest to the larger statistics community. In many applications including so-called the “large p small n” setting, the estimate of the covariance matrix is required to be not only invertible, but also well-conditioned. Although many regularization schemes attempt to do this, none of them address the ill-conditioning problem directly. In this paper, we propose a maximum likelihood approach, with the direct goal of obtaining a well-conditioned estimator. No sparsity assumption on either the covariance matrix or its inverse are are imposed, thus making our procedure more widely applicable. We demonstrate that the proposed regularization scheme is computationally efficient, yields a type of Steinian shrinkage estimator, and has a natural Bayesian interpretation. We investigate the theoretical properties of the regularized covariance estimator comprehensively, including its regularization path, and proceed to develop an approach that adaptively determines the level of regularization that is required. Finally, we demonstrate the performance of the regularized estimator in decision-theoretic comparisons and in the financial portfolio optimization setting. The proposed approach has desirable properties, and can serve as a competitive procedure, especially when the sample size is small and when a well-conditioned estimator is required. PMID:23730197
Universality in the flooding of regular islands by chaotic states.
Bäcker, Arnd; Ketzmerick, Roland; Monastra, Alejandro G
2007-06-01
We investigate the structure of eigenstates in systems with a mixed phase space in terms of their projection onto individual regular tori. Depending on dynamical tunneling rates and the Heisenberg time, regular states disappear and chaotic states flood the regular tori. For a quantitative understanding we introduce a random matrix model. The resulting statistical properties of eigenstates as a function of an effective coupling strength are in very good agreement with numerical results for a kicked system. We discuss the implications of these results for the applicability of the semiclassical eigenfunction hypothesis.
Regularized Kernel Forms of Minimum Squared Error Method
XU Jian-hua; ZHANG Xue-gong; LI Yan-da
2006-01-01
Minimum squared error (MSE) algorithm is one of the classical pattern recognition and regression analysis methods,whose objective is to minimize the squared error summation between the output of linear function and the desired output.In this paper,the MSE algorithm is modified by using kernel functions satisfying the Mercer condition and regularization technique; and the nonlinear MSE algorithms based on kernels and regularization term,that is,the regularized kernel forms of MSE algorithm,are proposed.Their objective functions include the squared error summation between the output of nonlinear function based on kernels and the desired output and a proper regularization term.The regularization technique can handle ill-posed problems,reduce the solution space,and control the generalization.Three squared regularization terms are utilized in this paper.In accordance with the probabilistic interpretation of regularization terms,the difference among three regularization terms is given in detail.The synthetic and real data are used to analyze the algorithm performance.
Homological Pisot Substitutions and Exact Regularity
Barge, Marcy; Jones, Leslie; Sadun, Lorenzo
2010-01-01
We consider one-dimensional substitution tiling spaces where the dilatation (stretching factor) is a degree d Pisot number, and where the first rational Cech cohomology is d-dimensional. We construct examples of such "homological Pisot" substitutions that do not have pure discrete spectra. These examples are not unimodular, and we conjecture that the coincidence rank must always divide a power of the norm of the dilatation. To support this conjecture, we show that homological Pisot substitutions exhibit an Exact Regularity Property (ERP), in which the number of occurrences of a patch for a return length is governed strictly by the length. The ERP puts strong constraints on the measure of any cylinder set in the corresponding tiling space.
Sparse regularization for force identification using dictionaries
Qiao, Baijie; Zhang, Xingwu; Wang, Chenxi; Zhang, Hang; Chen, Xuefeng
2016-04-01
The classical function expansion method based on minimizing l2-norm of the response residual employs various basis functions to represent the unknown force. Its difficulty lies in determining the optimum number of basis functions. Considering the sparsity of force in the time domain or in other basis space, we develop a general sparse regularization method based on minimizing l1-norm of the coefficient vector of basis functions. The number of basis functions is adaptively determined by minimizing the number of nonzero components in the coefficient vector during the sparse regularization process. First, according to the profile of the unknown force, the dictionary composed of basis functions is determined. Second, a sparsity convex optimization model for force identification is constructed. Third, given the transfer function and the operational response, Sparse reconstruction by separable approximation (SpaRSA) is developed to solve the sparse regularization problem of force identification. Finally, experiments including identification of impact and harmonic forces are conducted on a cantilever thin plate structure to illustrate the effectiveness and applicability of SpaRSA. Besides the Dirac dictionary, other three sparse dictionaries including Db6 wavelets, Sym4 wavelets and cubic B-spline functions can also accurately identify both the single and double impact forces from highly noisy responses in a sparse representation frame. The discrete cosine functions can also successfully reconstruct the harmonic forces including the sinusoidal, square and triangular forces. Conversely, the traditional Tikhonov regularization method with the L-curve criterion fails to identify both the impact and harmonic forces in these cases.
Quotient Complexity of Regular Languages
Janusz Brzozowski
2009-07-01
Full Text Available The past research on the state complexity of operations on regular languages is examined, and a new approach based on an old method (derivatives of regular expressions is presented. Since state complexity is a property of a language, it is appropriate to define it in formal-language terms as the number of distinct quotients of the language, and to call it "quotient complexity". The problem of finding the quotient complexity of a language f(K,L is considered, where K and L are regular languages and f is a regular operation, for example, union or concatenation. Since quotients can be represented by derivatives, one can find a formula for the typical quotient of f(K,L in terms of the quotients of K and L. To obtain an upper bound on the number of quotients of f(K,L all one has to do is count how many such quotients are possible, and this makes automaton constructions unnecessary. The advantages of this point of view are illustrated by many examples. Moreover, new general observations are presented to help in the estimation of the upper bounds on quotient complexity of regular operations.
Efficient Hyperelastic Regularization for Registration
Darkner, Sune; Hansen, Michael Sass; Larsen, Rasmus;
2011-01-01
For most image registration problems a smooth one-to-one mapping is desirable, a diffeomorphism. This can be obtained using priors such as volume preservation, certain kinds of elasticity or both. The key principle is to regularize the strain of the deformation which can be done through penalizat......For most image registration problems a smooth one-to-one mapping is desirable, a diffeomorphism. This can be obtained using priors such as volume preservation, certain kinds of elasticity or both. The key principle is to regularize the strain of the deformation which can be done through...... penalization of the eigen values of the stress tensor. We present a computational framework for regularization of image registration for isotropic hyper elasticity. We formulate an efficient and parallel scheme for computing the principal stain based for a given parameterization by decomposing the left Cauchy...
Regular algebra and finite machines
Conway, John Horton
2012-01-01
World-famous mathematician John H. Conway based this classic text on a 1966 course he taught at Cambridge University. Geared toward graduate students of mathematics, it will also prove a valuable guide to researchers and professional mathematicians.His topics cover Moore's theory of experiments, Kleene's theory of regular events and expressions, Kleene algebras, the differential calculus of events, factors and the factor matrix, and the theory of operators. Additional subjects include event classes and operator classes, some regulator algebras, context-free languages, communicative regular alg
陶晓; 赵竑绯; 徐小牛
2011-01-01
Soil samples were collected from six different types of green space in Hefei, East China, including suburban forest park, green land of residential area, roadside green space, campus green space, park green space, and factory green space. The change in content of Dissolved Organic Carbon (DOC) in soil under different types of urban green space was analyzed in order to increase the understanding of the impact of land use types and planting modes on carbon dynamics in urban soil, and to determine the relationships between DOC and other soil nutrients. Results suggested that the content of DOC decreased with soil depth, with average contents of 33.12 mg ? Kg-1 in 0-10 cm, 28. 89 mg ? Kg in 10-20 cm and 25.57 mg ? Kg"1 in 20-30 cm. The content of DOC in Shushan forest park (44. 28 mg ? Kg"1) was the highest, followed by campus green space (29. 84) , park green space (28. 39) , green land of residential area (26. 82) , roadside green space (26.72) , and factory green space (22.88). Planting modes also significantly impacted the content of DOC (P<0.05). The highest content of DOC was observed in the soil under arbor-herb mode, with an average of 44. 96 mg ? Kg-1 in 0-30 cm. Land use change resulted in an obvious variation in content of DOC in soil (0-30 cm) across the environmental gradi ent. The correlation analysis indicated that soil DOC content was positively correlated with soil moisture and NH4-N con tent, and significantly negatively correlated with pH (H2O) , pH (KC1) , bulk density, electrical conductivity, and total phosphorus content.%为探讨绿地类型及植被配置模式对城市土壤碳动态的影响,以合肥市绿地土壤为研究对象,分析了不同绿地类型(公园绿地、居住区绿地、道路绿地、工厂绿地、校园绿地)不同植被配置模式下土壤溶解性有机碳质量分数变化规律.结果表明:研究区内土壤溶解性有机碳平均质量分数随土层深度的增加而降低,0～ 10 cm、10～20 cm、20 ～ 30
彭威; 关昌峰; 阎华; 张震; 丁玉梅; 杨卫民
2013-01-01
The heat transfer and friction characteristics of tubes fitted with full length and regularly spaced grooved helical lobe rotor strands, with involved space ratios of 0. 0, 3. 0, 6. 0 and 10. 0, have been investigated experimentally. The Nusselt numbers of tubes with full length strands increased by factors of 0. 8 -1.2 times the empirical correlation results for plain tubes with the same Reynolds numbers, while the friction factor also increased by a-bout 55 % . The introduction of free spacing length weakened the disturbance of fluid flow, resulting in a decrease in heat transfer characteristics and tube side pressure drop at the same time. Performance evaluation criteria ( PEC) of strands with different space ratios were compared, and the results indicated that in the experimental Reynolds number range, an increase in space ratio resulted in a beneficial increase in PEC for low Reynolds number, while the PEC values of regularly spaced strands were lower than those of full length strands when the Reynolds number was relatively high.%以开槽螺旋叶片转子为研究对象,对装有空隙比S=0.0、3.0、6.0和10.0间隔排布转子串换热管的传热和阻力特性进行了实验研究.结果表明,装有空隙比S=0.0的整串转子串换热管的努塞尔数比同雷诺数下光管经验公式值提高了0.8～1.2倍,但阻力系数也提高了55％左右；转子串间留出一定间隙,虽会减弱管内流体扰动使换热管传热性能有所降低,但也显著降低了管内压降.采用综合评价指标(PEC)对4种空隙比转子串的传热和阻力特性进行综合比较,在实验雷诺数范围内,当雷诺数较低时,适当增加转子串的空隙比能够提高其综合传热性能；当雷诺数较高时,在转子串间留出间隙会使其综合传热性能低于整串转子.
Regularized Statistical Analysis of Anatomy
Sjöstrand, Karl
2007-01-01
This thesis presents the application and development of regularized methods for the statistical analysis of anatomical structures. Focus is on structure-function relationships in the human brain, such as the connection between early onset of Alzheimer’s disease and shape changes of the corpus cal...
Regularization in Matrix Relevance Learning
Schneider, Petra; Bunte, Kerstin; Stiekema, Han; Hammer, Barbara; Villmann, Thomas; Biehl, Michael
2010-01-01
A In this paper, we present a regularization technique to extend recently proposed matrix learning schemes in learning vector quantization (LVQ). These learning algorithms extend the concept of adaptive distance measures in LVQ to the use of relevance matrices. In general, metric learning can displa
Singularities of slice regular functions
Stoppato, Caterina
2010-01-01
Beginning in 2006, G. Gentili and D.C. Struppa developed a theory of regular quaternionic functions with properties that recall classical results in complex analysis. For instance, in each Euclidean ball centered at 0 the set of regular functions coincides with that of quaternionic power series converging in the same ball. In 2009 the author proposed a classification of singularities of regular functions as removable, essential or as poles and studied poles by constructing the ring of quotients. In that article, not only the statements, but also the proving techniques were confined to the special case of balls centered at 0. In a subsequent paper, F. Colombo, G. Gentili, I. Sabadini and D.C. Struppa (2009) identified a larger class of domains, on which the theory of regular functions is natural and not limited to quaternionic power series. The present article studies singularities in this new context, beginning with the construction of the ring of quotients and of Laurent-type expansions at points other than ...
Regular inference as vertex coloring
Costa Florêncio, C.; Verwer, S.
2012-01-01
This paper is concerned with the problem of supervised learning of deterministic finite state automata, in the technical sense of identification in the limit from complete data, by finding a minimal DFA consistent with the data (regular inference). We solve this problem by translating it in its enti
Regularized Generalized Structured Component Analysis
Hwang, Heungsun
2009-01-01
Generalized structured component analysis (GSCA) has been proposed as a component-based approach to structural equation modeling. In practice, GSCA may suffer from multi-collinearity, i.e., high correlations among exogenous variables. GSCA has yet no remedy for this problem. Thus, a regularized extension of GSCA is proposed that integrates a ridge…
Regular inference as vertex coloring
Costa Florêncio, C.; Verwer, S.
2012-01-01
This paper is concerned with the problem of supervised learning of deterministic finite state automata, in the technical sense of identification in the limit from complete data, by finding a minimal DFA consistent with the data (regular inference). We solve this problem by translating it in its
2011-01-20
... meeting of the Board will be held at the offices of the Farm Credit Administration in McLean, Virginia, on...Lean, Virginia 22102. SUPPLEMENTARY INFORMATION: This meeting of the Board will be open to the ] public... CORPORATION Farm Credit System Insurance Corporation Board Regular Meeting SUMMARY: Notice is hereby given of...
Lavrentiev regularization method for nonlinear ill-posed problems
Kinh, N V
2002-01-01
In this paper we shall be concerned with Lavientiev regularization method to reconstruct solutions x sub 0 of non ill-posed problems F(x)=y sub o , where instead of y sub 0 noisy data y subdelta is an element of X with absolut(y subdelta-y sub 0) X is an accretive nonlinear operator from a real reflexive Banach space X into itself. In this regularization method solutions x subalpha supdelta are obtained by solving the singularly perturbed nonlinear operator equation F(x)+alpha(x-x*)=y subdelta with some initial guess x*. Assuming certain conditions concerning the operator F and the smoothness of the element x*-x sub 0 we derive stability estimates which show that the accuracy of the regularized solutions is order optimal provided that the regularization parameter alpha has been chosen properly.
Buong, Nguyen; Dung, Nguyen Dinh
2014-03-01
In this paper, we present a regularized parameter choice in a new regularization method of Browder-Tikhonov type, for finding a common solution of a finite system of ill-posed operator equations involving Lipschitz continuous and accretive mappings in a real reflexive and strictly convex Banach space with a uniformly Gateaux differentiate norm. An estimate for convergence rates of regularized solution is also established.
Global regular solutions for Landau-Lifshitz equation
GUO Boling; HAN Yongqian
2006-01-01
In this note,we prove that there exists a unique global regular solution for multidimensional Landau-Lifshitz equation if the gradient of solutions can be bounded in space L2(0,T;L∞).Moreover,for the twodimensional radial symmetric Landau-Lifshitz equation with Neumann boundary condition in the exterior domain,this hypothesis in space L2(0,T;L∞) can be cancelled.
Impulse Observability and Impulse Controllability of Regular Degenerate Evolution Systems
GE Zhaoqiang
2016-01-01
Impulse observability and impulse controllability of regular degenerate evolution systems are discussed by using functional analysis and operator theory in Banach space.Necessary and sufficient conditions for the impulse observability and impulse controllability of the system are obtained.This research is theoretically important for studying the design of the degenerate evolution system.
Regular Caratheodory-type selectors under no convexity assumptions
Chistyakov, VV
2005-01-01
We prove the existence of Caratheodory-type selectors (that is, measurable in the first variable and having certain regularity properties like Lipschitz continuity, absolute continuity or bounded variation in the second variable) for multifunctions mapping the product of a measurable space and an in
General inverse problems for regular variation
Damek, Ewa; Mikosch, Thomas Valentin; Rosinski, Jan
2014-01-01
Regular variation of distributional tails is known to be preserved by various linear transformations of some random structures. An inverse problem for regular variation aims at understanding whether the regular variation of a transformed random object is caused by regular variation of components ...
Regular Motions of Resonant Asteroids
Ferraz-Mello, S.
1990-11-01
RESUMEN. Se revisan resultados analiticos relativos a soluciones regulares del problema asteroidal eliptico promediados en la vecindad de una resonancia con jupiten Mencionamos Ia ley de estructura para libradores de alta excentricidad, la estabilidad de los centros de liberaci6n, las perturbaciones forzadas por la excentricidad de jupiter y las 6rbitas de corotaci6n. ABSTRAC This paper reviews analytical results concerning the regular solutions of the elliptic asteroidal problem averaged in the neighbourhood of a resonance with jupiter. We mention the law of structure for high-eccentricity librators, the stability of the libration centers, the perturbations forced by the eccentricity ofjupiter and the corotation orbits. Key words: ASThROIDS
Energy functions for regularization algorithms
Delingette, H.; Hebert, M.; Ikeuchi, K.
1991-01-01
Regularization techniques are widely used for inverse problem solving in computer vision such as surface reconstruction, edge detection, or optical flow estimation. Energy functions used for regularization algorithms measure how smooth a curve or surface is, and to render acceptable solutions these energies must verify certain properties such as invariance with Euclidean transformations or invariance with parameterization. The notion of smoothness energy is extended here to the notion of a differential stabilizer, and it is shown that to void the systematic underestimation of undercurvature for planar curve fitting, it is necessary that circles be the curves of maximum smoothness. A set of stabilizers is proposed that meet this condition as well as invariance with rotation and parameterization.
Maximum mutual information regularized classification
Wang, Jim Jing-Yan
2014-09-07
In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.
Graph Regularized Auto-Encoders for Image Representation.
Yiyi Liao; Yue Wang; Yong Liu
2017-06-01
Image representation has been intensively explored in the domain of computer vision for its significant influence on the relative tasks such as image clustering and classification. It is valuable to learn a low-dimensional representation of an image which preserves its inherent information from the original image space. At the perspective of manifold learning, this is implemented with the local invariant idea to capture the intrinsic low-dimensional manifold embedded in the high-dimensional input space. Inspired by the recent successes of deep architectures, we propose a local invariant deep nonlinear mapping algorithm, called graph regularized auto-encoder (GAE). With the graph regularization, the proposed method preserves the local connectivity from the original image space to the representation space, while the stacked auto-encoders provide explicit encoding model for fast inference and powerful expressive capacity for complex modeling. Theoretical analysis shows that the graph regularizer penalizes the weighted Frobenius norm of the Jacobian matrix of the encoder mapping, where the weight matrix captures the local property in the input space. Furthermore, the underlying effects on the hidden representation space are revealed, providing insightful explanation to the advantage of the proposed method. Finally, the experimental results on both clustering and classification tasks demonstrate the effectiveness of our GAE as well as the correctness of the proposed theoretical analysis, and it also suggests that GAE is a superior solution to the current deep representation learning techniques comparing with variant auto-encoders and existing local invariant methods.
Fast regularized image interpolation method
Hongchen Liu; Yong Feng; Linjing Li
2007-01-01
The regularized image interpolation method is widely used based on the vector interpolation model in which down-sampling matrix has very large dimension and needs large storage consumption and higher computation complexity. In this paper, a fast algorithm for image interpolation based on the tensor product of matrices is presented, which transforms the vector interpolation model to matrix form. The proposed algorithm can extremely reduce the storage requirement and time consumption. The simulation results verify their validity.
Efficient Hyperelastic Regularization for Registration
Darkner, Sune; Hansen, Michael S; Larsen, Rasmus;
2011-01-01
For most image registration problems a smooth one-to-one mapping is desirable, a diffeomorphism. This can be obtained using priors such as volume preservation, certain kinds of elasticity or both. The key principle is to regularize the strain of the deformation which can be done through penalizat......For most image registration problems a smooth one-to-one mapping is desirable, a diffeomorphism. This can be obtained using priors such as volume preservation, certain kinds of elasticity or both. The key principle is to regularize the strain of the deformation which can be done through...... penalization of the eigen values of the stress tensor. We present a computational framework for regularization of image registration for isotropic hyper elasticity. We formulate an efficient and parallel scheme for computing the principal stain based for a given parameterization by decomposing the left Cauchy...... elastic priors such at the Saint Vernant Kirchoff model, the Ogden material model or Riemanian elasticity. We exemplify the approach through synthetic registration and special tests as well as registration of different modalities; 2D cardiac MRI and 3D surfaces of the human ear. The artificial examples...
From Dimensional to Cut-Off Regularization
Dillig, M
2006-01-01
We extent the standard approach of dimensional regularization of Feynman diagrams: we replace the transition to lower dimensions by a 'natural' cut-off regulator. Introducing an external regulator of mass Lambda^(2e), we regain in the limit e -> 0 and e > 0 the results of dimensional and cut-off regularization, respectively. We demonstrate the versatility and adequacy of the different regularization schemes for practical examples (such as non covariant regularization, the axial anomaly or regularization in effective field theories).
Thermodynamics of regular accelerating black holes
Astorino, Marco
2017-03-01
Using the covariant phase space formalism, we compute the conserved charges for a solution, describing an accelerating and electrically charged Reissner-Nordstrom black hole. The metric is regular provided that the acceleration is driven by an external electric field, in spite of the usual string of the standard C-metric. The Smarr formula and the first law of black hole thermodynamics are fulfilled. The resulting mass has the same form of the Christodoulou-Ruffini irreducible mass. On the basis of these results, we can extrapolate the mass and thermodynamics of the rotating C-metric, which describes a Kerr-Newman-(A)dS black hole accelerated by a pulling string.
Trembach, Vera
2014-01-01
Space is an introduction to the mysteries of the Universe. Included are Task Cards for independent learning, Journal Word Cards for creative writing, and Hands-On Activities for reinforcing skills in Math and Language Arts. Space is a perfect introduction to further research of the Solar System.
Quantitative regularities in floodplain formation
Nevidimova, O.
2009-04-01
Quantitative regularities in floodplain formation Modern methods of the theory of complex systems allow to build mathematical models of complex systems where self-organizing processes are largely determined by nonlinear effects and feedback. However, there exist some factors that exert significant influence on the dynamics of geomorphosystems, but hardly can be adequately expressed in the language of mathematical models. Conceptual modeling allows us to overcome this difficulty. It is based on the methods of synergetic, which, together with the theory of dynamic systems and classical geomorphology, enable to display the dynamics of geomorphological systems. The most adequate for mathematical modeling of complex systems is the concept of model dynamics based on equilibrium. This concept is based on dynamic equilibrium, the tendency to which is observed in the evolution of all geomorphosystems. As an objective law, it is revealed in the evolution of fluvial relief in general, and in river channel processes in particular, demonstrating the ability of these systems to self-organization. Channel process is expressed in the formation of river reaches, rifts, meanders and floodplain. As floodplain is a periodically flooded surface during high waters, it naturally connects river channel with slopes, being one of boundary expressions of the water stream activity. Floodplain dynamics is inseparable from the channel dynamics. It is formed at simultaneous horizontal and vertical displacement of the river channel, that is at Y=Y(x, y), where х, y - horizontal and vertical coordinates, Y - floodplain height. When dу/dt=0 (for not lowering river channel), the river, being displaced in a horizontal plane, leaves behind a low surface, which flooding during high waters (total duration of flooding) changes from the maximum during the initial moment of time t0 to zero in the moment tn. In a similar manner changed is the total amount of accumulated material on the floodplain surface
Regularized degenerate multi-solitons
Correa, Francisco
2016-01-01
We report complex PT-symmetric multi-soliton solutions to the Korteweg de-Vries equation that asymptotically contain one-soliton solutions, with each of them possessing the same amount of finite real energy. We demonstrate how these solutions originate from degenerate energy solutions of the Schroedinger equation. Technically this is achieved by the application of Darboux-Crum transformations involving Jordan states with suitable regularizing shifts. Alternatively they may be constructed from a limiting process within the context Hirota's direct method or on a nonlinear superposition obtained from multiple Baecklund transformations. The proposed procedure is completely generic and also applicable to other types of nonlinear integrable systems.
Academic Training Lecture - Regular Programme
PH Department
2011-01-01
Regular Lecture Programme 9 May 2011 ACT Lectures on Detectors - Inner Tracking Detectors by Pippa Wells (CERN) 10 May 2011 ACT Lectures on Detectors - Calorimeters (2/5) by Philippe Bloch (CERN) 11 May 2011 ACT Lectures on Detectors - Muon systems (3/5) by Kerstin Hoepfner (RWTH Aachen) 12 May 2011 ACT Lectures on Detectors - Particle Identification and Forward Detectors by Peter Krizan (University of Ljubljana and J. Stefan Institute, Ljubljana, Slovenia) 13 May 2011 ACT Lectures on Detectors - Trigger and Data Acquisition (5/5) by Dr. Brian Petersen (CERN) from 11:00 to 12:00 at CERN ( Bldg. 222-R-001 - Filtration Plant )
Weir, Maurice D
2013-01-01
North-Holland Mathematics Studies: Hewitt-Nachbin Spaces exposes the theory of Hewitt-Nachbin spaces, also called realcompact or Q-spaces, taking into account synergistic points of view from which these spaces are investigated. The publication first offers information on embedding in topological products and Hewitt-Nachbin spaces and convergence, including notation and terminology, embedding lemma, E-completely regular spaces, E-compact spaces, and characterizations and properties of Hewitt-Nachbin spaces. The text also touches on Hewitt-Nachbin spaces, uniformities, and related topological sp
Chen, De-Han; Hofmann, Bernd; Zou, Jun
2017-01-01
We consider the ill-posed operator equation Ax = y with an injective and bounded linear operator A mapping between {{\\ell}2} and a Hilbert space Y, possessing the unique solution {{x}\\dagger}=≤ft\\{{{x}\\dagger}k\\right\\}k=1∞ . For the cases that sparsity {{x}\\dagger}\\in {{\\ell}0} is expected but often slightly violated in practice, we investigate in comparison with the {{\\ell}1} -regularization the elastic-net regularization, where the penalty is a weighted superposition of the {{\\ell}1} -norm and the {{\\ell}2} -norm square, under the assumption that {{x}\\dagger}\\in {{\\ell}1} . There occur two positive parameters in this approach, the weight parameter η and the regularization parameter as the multiplier of the whole penalty in the Tikhonov functional, whereas only one regularization parameter arises in {{\\ell}1} -regularization. Based on the variational inequality approach for the description of the solution smoothness with respect to the forward operator A and exploiting the method of approximate source conditions, we present some results to estimate the rate of convergence for the elastic-net regularization. The occurring rate function contains the rate of the decay {{x}\\dagger}k\\to 0 for k\\to ∞ and the classical smoothness properties of {{x}\\dagger} as an element in {{\\ell}2} .
Smoothness spaces of higher order on lower dimensional subsets of the Euclidean space
Ihnatsyeva, Lizaveta
2011-01-01
We study Sobolev type spaces defined in terms of sharp maximal functions on Ahlfors regular subsets of the Euclidean space and the relation between these spaces and traces of classical Sobolev spaces.
Estimating signal loss in regularized GRACE gravity field solutions
Swenson, S. C.; Wahr, J. M.
2011-05-01
Gravity field solutions produced using data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are subject to errors that increase as a function of increasing spatial resolution. Two commonly used techniques to improve the signal-to-noise ratio in the gravity field solutions are post-processing, via spectral filters, and regularization, which occurs within the least-squares inversion process used to create the solutions. One advantage of post-processing methods is the ability to easily estimate the signal loss resulting from the application of the spectral filter by applying the filter to synthetic gravity field coefficients derived from models of mass variation. This is a critical step in the construction of an accurate error budget. Estimating the amount of signal loss due to regularization, however, requires the execution of the full gravity field determination process to create synthetic instrument data; this leads to a significant cost in computation and expertise relative to post-processing techniques, and inhibits the rapid development of optimal regularization weighting schemes. Thus, while a number of studies have quantified the effects of spectral filtering, signal modification in regularized GRACE gravity field solutions has not yet been estimated. In this study, we examine the effect of one regularization method. First, we demonstrate that regularization can in fact be performed as a post-processing step if the solution covariance matrix is available. Regularization then is applied as a post-processing step to unconstrained solutions from the Center for Space Research (CSR), using weights reported by the Centre National d'Etudes Spatiales/Groupe de Recherches de geodesie spatiale (CNES/GRGS). After regularization, the power spectra of the CSR solutions agree well with those of the CNES/GRGS solutions. Finally, regularization is performed on synthetic gravity field solutions derived from a land surface model, revealing that in
Wave dynamics of regular and chaotic rays
McDonald, S.W.
1983-09-01
In order to investigate general relationships between waves and rays in chaotic systems, I study the eigenfunctions and spectrum of a simple model, the two-dimensional Helmholtz equation in a stadium boundary, for which the rays are ergodic. Statistical measurements are performed so that the apparent randomness of the stadium modes can be quantitatively contrasted with the familiar regularities observed for the modes in a circular boundary (with integrable rays). The local spatial autocorrelation of the eigenfunctions is constructed in order to indirectly test theoretical predictions for the nature of the Wigner distribution corresponding to chaotic waves. A portion of the large-eigenvalue spectrum is computed and reported in an appendix; the probability distribution of successive level spacings is analyzed and compared with theoretical predictions. The two principal conclusions are: 1) waves associated with chaotic rays may exhibit randomly situated localized regions of high intensity; 2) the Wigner function for these waves may depart significantly from being uniformly distributed over the surface of constant frequency in the ray phase space.
WEAK REGULARIZATION FOR A CLASS OF ILL-POSED CAUCHY PROBLEMS
无
2006-01-01
This article is concerned with the ill-posed Cauchy problem associated with a densely defined linear operator A in a Banach space. A family of weak regularizing operators is introduced. If the spectrum of A is contained in a sector of right-half complex plane and its resolvent is polynomially bounded, the weak regularization for such ill-posed Cauchy problem can be shown by using the quasi-reversibility method and regularized semigroups. Finally, an example is given.
Robust integral stabilization of regular linear systems
XU Chengzheng; FENG Dexing
2004-01-01
We consider regular systems with control and observation. We prove some necessary and sufficient condition for an exponentially stable regular system to admit an integral stabilizing controller. We propose also some robust integral controllers when they exist.
Generalization performance of regularized neural network models
Larsen, Jan; Hansen, Lars Kai
1994-01-01
Architecture optimization is a fundamental problem of neural network modeling. The optimal architecture is defined as the one which minimizes the generalization error. This paper addresses estimation of the generalization performance of regularized, complete neural network models. Regularization...
Regularized quadratic cost function for oriented fringe-pattern filtering.
Villa, Jesús; Quiroga, Juan Antonio; De la Rosa, Ismael
2009-06-01
We use the regularization theory in a Bayesian framework to derive a quadratic cost function for denoising fringe patterns. As prior constraints for the regularization problem, we propose a Markov random field model that includes information about the fringe orientation. In our cost function the regularization term imposes constraints to the solution (i.e., the filtered image) to be smooth only along the fringe's tangent direction. In this way as the fringe information and noise are conveniently separated in the frequency space, our technique avoids blurring the fringes. The attractiveness of the proposed filtering method is that the minimization of the cost function can be easily implemented using iterative methods. To show the performance of the proposed technique we present some results obtained by processing simulated and real fringe patterns.
Adiabatic Regularization for Gauge Field and the Conformal Anomaly
Chu, Chong-Sun
2016-01-01
We construct and provide the adiabatic regularization method for a $U(1)$ gauge field in a conformally flat spacetime by quantizing in the canonical formalism the gauge fixed $U(1)$ theory with mass terms for the gauge fields and the ghost fields. We show that the adiabatic expansion for the mode functions and the adiabatic vacuum can be defined in a similar way using WKB-type solutions as the scalar fields. As an application of the adiabatic method, we compute the trace of the energy momentum tensor and reproduces the known result for the conformal anomaly obtained by the other regularization methods. The availability of the adiabatic expansion scheme for gauge field allows one to study the renormalization of the de-Sitter space maximal superconformal Yang-Mills theory using the adiabatic regularization method.
Some remarks on regular subgroups of the affine group
M. Chiara Tamburini Bellani
2012-03-01
Full Text Available Let $V$ be a vector space over a field $F$ of characteristic $pgeq 0$ and let $T$ be a regular subgroup of the affine group $AGL(V$. In the finite dimensional case we show that, if $T$ is abelian or $p>0$, then $T$ is unipotent. For $T$ abelian, pushing forward some ideas used in [A. Caranti, F. Dalla Volta and M. Sala, Abelian regular subgroups of the affine group and radical rings, Publ. Math. Debrecen {bf 69} (2006, 297--308.], we show that the set $left{t-Imid tin Tright}$ is a subalgebra of $End_F(Foplus V$, which is nilpotent when $V$ has finite dimension. This allows a rather systematic construction of abelian regular subgroups.
A FAST CONVERGENT METHOD OF ITERATED REGULARIZATION
Huang Xiaowei; Wu Chuansheng; Wu Di
2009-01-01
This article presents a fast convergent method of iterated regularization based on the idea of Landweber iterated regularization, and a method for a-posteriori choice by the Morozov discrepancy principle and the optimum asymptotic convergence order of the regularized solution is obtained. Numerical test shows that the method of iterated regu-larization can quicken the convergence speed and reduce the calculation burden efficiently.
Weakly and Strongly Regular Near-rings
N.Argac; N.J.Groenewald
2005-01-01
In this paper, we prove some basic properties of left weakly regular near-rings.We give an affirmative answer to the question whether a left weakly regular near-ring with left unity and satisfying the IFP is also right weakly regular. In the last section, we use among others left 0-prime and left completely prime ideals to characterize strongly regular near-rings.
MAXIMAL POINTS OF A REGULAR TRUTH FUNCTION
Every canonical linearly separable truth function is a regular function, but not every regular truth function is linearly separable. The most...promising method of determining which of the regular truth functions are linearly separable r quires finding their maximal and minimal points. In this...report is developed a quick, systematic method of finding the maximal points of any regular truth function in terms of its arithmetic invariants. (Author)
Natural frequency of regular basins
Tjandra, Sugih S.; Pudjaprasetya, S. R.
2014-03-01
Similar to the vibration of a guitar string or an elastic membrane, water waves in an enclosed basin undergo standing oscillatory waves, also known as seiches. The resonant (eigen) periods of seiches are determined by water depth and geometry of the basin. For regular basins, explicit formulas are available. Resonance occurs when the dominant frequency of external force matches the eigen frequency of the basin. In this paper, we implement the conservative finite volume scheme to 2D shallow water equation to simulate resonance in closed basins. Further, we would like to use this scheme and utilizing energy spectra of the recorded signal to extract resonant periods of arbitrary basins. But here we first test the procedure for getting resonant periods of a square closed basin. The numerical resonant periods that we obtain are comparable with those from analytical formulas.
Regularized degenerate multi-solitons
Correa, Francisco; Fring, Andreas
2016-09-01
We report complex {P}{T} -symmetric multi-soliton solutions to the Korteweg de-Vries equation that asymptotically contain one-soliton solutions, with each of them possessing the same amount of finite real energy. We demonstrate how these solutions originate from degenerate energy solutions of the Schrödinger equation. Technically this is achieved by the application of Darboux-Crum transformations involving Jordan states with suitable regularizing shifts. Alternatively they may be constructed from a limiting process within the context Hirota's direct method or on a nonlinear superposition obtained from multiple Bäcklund transformations. The proposed procedure is completely generic and also applicable to other types of nonlinear integrable systems.
REGULARITY FOR CERTAIN QUASILINEARELLIPTIC SYSTEMS OF DIVERGENCESTRUCTURE
周树清; 冉启康
2001-01-01
The regularity of the gradient of H lder continuous solutions of quasi-linear elliptic systems of the form -Dj(aij(x, u, Du)Diuk) = -Difik + gkis investigated. Partial regularity and ε-regularity are shown to hold under the structural assumption-Dj(aij(x,u, Du)) = hi ∈ L∞.
Technology Corner: A Regular Expression Training App
Nick Flor
2012-12-01
Full Text Available Regular expressions enable digital forensic analysts to find information in files. The best way for an analyst to become proficient in writing regular expressions is to practice. This paper presents the code for an app that allows an analyst to practice writing regular expressions.
Counting Rooted Nearly 2-regular Planar Maps
郝荣霞; 蔡俊亮
2004-01-01
The number of rooted nearly 2-regular maps with the valency of rootvertex, the number of non-rooted vertices and the valency of root-face as three parameters is obtained. Furthermore, the explicit expressions of the special cases including loopless nearly 2-regular maps and simple nearly 2-regular maps in terms of the above three parameters are derived.
On the Construction of Regular Orthocryptogroups
Xiang Zhi KONG
2002-01-01
The aim of this paper is to study regular orthocryptogroups. After obtaining some charac-terizations of such semigroups, we establish the construction theorem of regular orthocryptogroups. Asan application, we give the construction theorem of right quasi-normal orthocryptogroups and studyhomomorphisms between two regular orthocryptogroups.
Regular Pentagons and the Fibonacci Sequence.
French, Doug
1989-01-01
Illustrates how to draw a regular pentagon. Shows the sequence of a succession of regular pentagons formed by extending the sides. Calculates the general formula of the Lucas and Fibonacci sequences. Presents a regular icosahedron as an example of the golden ratio. (YP)
Discriminative Elastic-Net Regularized Linear Regression.
Zhang, Zheng; Lai, Zhihui; Xu, Yong; Shao, Ling; Wu, Jian; Xie, Guo-Sen
2017-03-01
In this paper, we aim at learning compact and discriminative linear regression models. Linear regression has been widely used in different problems. However, most of the existing linear regression methods exploit the conventional zero-one matrix as the regression targets, which greatly narrows the flexibility of the regression model. Another major limitation of these methods is that the learned projection matrix fails to precisely project the image features to the target space due to their weak discriminative capability. To this end, we present an elastic-net regularized linear regression (ENLR) framework, and develop two robust linear regression models which possess the following special characteristics. First, our methods exploit two particular strategies to enlarge the margins of different classes by relaxing the strict binary targets into a more feasible variable matrix. Second, a robust elastic-net regularization of singular values is introduced to enhance the compactness and effectiveness of the learned projection matrix. Third, the resulting optimization problem of ENLR has a closed-form solution in each iteration, which can be solved efficiently. Finally, rather than directly exploiting the projection matrix for recognition, our methods employ the transformed features as the new discriminate representations to make final image classification. Compared with the traditional linear regression model and some of its variants, our method is much more accurate in image classification. Extensive experiments conducted on publicly available data sets well demonstrate that the proposed framework can outperform the state-of-the-art methods. The MATLAB codes of our methods can be available at http://www.yongxu.org/lunwen.html.
Regularization method with two parameters for nonlinear ill-posed problems
2008-01-01
This paper is devoted to the regularization of a class of nonlinear ill-posed problems in Banach spaces. The operators involved are multi-valued and the data are assumed to be known approximately. Under the assumption that the original problem is solvable, a strongly convergent approximation procedure is designed by means of the Tikhonov regularization method with two pa- rameters.
Academic Training Lecture Regular Programme
2012-01-01
AMS_02 Particle Physics Detector Technologies Orbiting the Earth (1/2), by Corrado Gargiulo (CERN). Thursday, April 19, 2012 from 11:00 to 12:30 (Europe/Zurich) at CERN ( 4-3-006 - TH Conference Room ) AMS-02 has taken the high performance technologies used in particle physics and implemented them for use in low Earth orbit. Safety aspects for the Space Shuttle flight, that carried AMS_02 to the International Space Station, Space environment and inaccessibility during the life of AMS_02 are some of the aspects which have driven the design of the experiment. The technical challenges to build such a detector have been surmounted through the close collaboration amongst the AMS scientists and industries around the world. Their efforts have resulted in the development of new technologies and higher standards of precision.
A New Regularization Mechanism for the Boltzmann Equation Without Cut-Off
Silvestre, Luis
2016-11-01
We apply recent results on regularity for general integro-differential equations to derive a priori estimates in Hölder spaces for the space homogeneous Boltzmann equation in the non cut-off case. We also show an a priori estimate in {L^∞} which applies in the space inhomogeneous case as well, provided that the macroscopic quantities remain bounded.
Convex-Faced Combinatorially Regular Polyhedra of Small Genus
Jörg M. Wills
2011-12-01
Full Text Available Combinatorially regular polyhedra are polyhedral realizations (embeddings in Euclidean 3-space E3 of regular maps on (orientable closed compact surfaces. They are close analogues of the Platonic solids. A surface of genus g ≥ 2 admits only finitely many regular maps, and generally only a small number of them can be realized as polyhedra with convex faces. When the genus g is small, meaning that g is in the historically motivated range 2 ≤ g ≤ 6, only eight regular maps of genus g are known to have polyhedral realizations, two discovered quite recently. These include spectacular convex-faced polyhedra realizing famous maps of Klein, Fricke, Dyck, and Coxeter. We provide supporting evidence that this list is complete; in other words, we strongly conjecture that in addition to those eight there are no other regular maps of genus g, with 2 ≤ g ≤ 6, admitting realizations as convex-faced polyhedra in E3. For all admissible maps in this range, save Gordan’s map of genus 4, and its dual, we rule out realizability by a polyhedron in E3.
Information fusion in regularized inversion of tomographic pumping tests
Bohling, G.C.; ,
2008-01-01
In this chapter we investigate a simple approach to incorporating geophysical information into the analysis of tomographic pumping tests for characterization of the hydraulic conductivity (K) field in an aquifer. A number of authors have suggested a tomographic approach to the analysis of hydraulic tests in aquifers - essentially simultaneous analysis of multiple tests or stresses on the flow system - in order to improve the resolution of the estimated parameter fields. However, even with a large amount of hydraulic data in hand, the inverse problem is still plagued by non-uniqueness and ill-conditioning and the parameter space for the inversion needs to be constrained in some sensible fashion in order to obtain plausible estimates of aquifer properties. For seismic and radar tomography problems, the parameter space is often constrained through the application of regularization terms that impose penalties on deviations of the estimated parameters from a prior or background model, with the tradeoff between data fit and model norm explored through systematic analysis of results for different levels of weighting on the regularization terms. In this study we apply systematic regularized inversion to analysis of tomographic pumping tests in an alluvial aquifer, taking advantage of the steady-shape flow regime exhibited in these tests to expedite the inversion process. In addition, we explore the possibility of incorporating geophysical information into the inversion through a regularization term relating the estimated K distribution to ground penetrating radar velocity and attenuation distributions through a smoothing spline model. ?? 2008 Springer-Verlag Berlin Heidelberg.
Effect of regularization parameters on geophysical reconstruction
Zhou Hui; Wang Zhaolei; Qiu Dongling; Li Guofa; Shen Jinsong
2009-01-01
In this paper we discuss the edge-preserving regularization method in the reconstruction of physical parameters from geophysical data such as seismic and ground-penetrating radar data.In the regularization method a potential function of model parameters and its corresponding functions are introduced.This method is stable and able to preserve boundaries, and protect resolution.The effect of regularization depends to a great extent on the suitable choice of regularization parameters.The influence of the edge-preserving parameters on the reconstruction results is investigated and the relationship between the regularization parameters and the error of data is described.
Global regularity criteria for the n-dimensional Boussinesq equations with fractional dissipation
Zujin Zhang
2016-04-01
Full Text Available We consider the n-dimensional Boussinesq equations with fractional dissipation, and establish a regularity criterion in terms of the velocity gradient in Besov spaces with negative order.
Regularity criterion to some liquid crystal models and the Landau-Lifshitz equations in R3
FAN JiShan; GUO BoLing
2008-01-01
We consider the regularity problem under the critical condition to some liquid crystal models and the Landau-Lifshitz equations.The Serrin type reularity criteria are obtained in the terms of the Besov spaces.
Regularity criterion to some liquid crystal models and the Landau-Lifshitz equations in R~3
2008-01-01
We consider the regularity problem under the critical condition to some liquid crystal models and the Landau-Lifshitz equations. The Serrin type reularity criteria are obtained in the terms of the Besov spaces.
Regular Black Holes with Cosmological Constant
MO Wen-Juan; CAI Rong-Gen; SU Ru-Keng
2006-01-01
We present a class of regular black holes with cosmological constant Λ in nonlinear electrodynamics. Instead of usual singularity behind black hole horizon, all fields and curvature invariants are regular everywhere for the regular black holes. Through gauge invariant approach, the linearly dynamical stability of the regular black hole is studied. In odd-parity sector, we find that the Λ term does not appear in the master equations of perturbations, which shows that the regular black hole is stable under odd-parity perturbations. On the other hand, for the even-parity sector, the master equations are more complicated than the case without the cosmological constant. We obtain the sufficient conditions for stability of the regular black hole. We also investigate the thermodynamic properties of the regular black hole, and find that those thermodynamic quantities do not satisfy the differential form of first law of black hole thermodynamics. The reason for violating the first law is revealed.
Matthews, Nyle J.
1989-01-01
A tiny pellet inserted under the skin of a calf's ear may increase weight gains as much as 15 to 20 percent. This same result would take years to accomplish through breeding and selection. These tiny pellets are growth stimulants. They are made of hormones that are constructed to slowly release minute amounts into the blood stream that stimulate the animal to produce natural body hormones. One of these hormones is a growth hormone. It regulates the rate of growth of the animal. Increasing the...
Partial Regularity for Holonomic Minimisers of Quasiconvex Functionals
Hopper, Christopher P.
2016-10-01
We prove partial regularity for local minimisers of certain strictly quasiconvex integral functionals, over a class of Sobolev mappings into a compact Riemannian manifold, to which such mappings are said to be holonomically constrained. Our approach uses the lifting of Sobolev mappings to the universal covering space, the connectedness of the covering space, an application of Ekeland's variational principle and a certain tangential A-harmonic approximation lemma obtained directly via a Lipschitz approximation argument. This allows regularity to be established directly on the level of the gradient. Several applications to variational problems in condensed matter physics with broken symmetries are also discussed, in particular those concerning the superfluidity of liquid helium-3 and nematic liquid crystals.
Towards regularized higher-order computations in QFT without DREG
Sborlini, German F R; Hernandez-Pinto, Roger; Rodrigo, German
2016-01-01
In this talk, we review the basis of the loop-tree duality theorem, which allows to rewrite loop scattering amplitudes in terms of tree-level like objects. Since the loop measure is converted into a phase-space one, both virtual and real contributions are expressible using the same integration variables. A physically motivated momentum mapping allows to generate the real emission process starting from the Born kinematics and the loop momenta. The integrand-level combination leads to regular functions, which can be integrated without using dimensional regularization (DREG) and correctly reproduce the finite higher-order corrections to physical observables. We explain the implementation of this novel approach to compute some benchmark physical processes, and we show how to deal with both infrared and ultraviolet divergences in four space-time dimensions.
On the Regularization of On-Shell Diagrams
Benincasa, Paolo; Gordo, David
2014-01-01
In this letter we discuss a regularization scheme for the integration of generic on-shell forms. The basic idea is to extend the three-particle amplitudes to the space of unphysical helicities keeping the dimension of the related coupling constant fixed, and construct on-shell forms out of them. We briefly discuss the analytic structure of the extended on-shell diagrams, both at tree level and one loop. Furthermore, we propose an integration contour which, applied to the relevant on-shell forms, allows to extract the four-particle amplitudes in Lorentz signature at one loop. With this contour at hand, we explicitly apply our procedure to this case obtaining the IR divergences as poles in the deformation parameter space, as well as the correct functional form for the finite term. This procedure provides a natural regularization for generic on-shell diagrams.
Flicker regularity is crucial for entrainment of alpha oscillations
Annika Notbohm
2016-10-01
Full Text Available Previous studies have shown that alpha oscillations (8-13 Hz in human electroencephalogram (EEG modulate perception via phase-dependent inhibition. If entrained to an external driving force, inhibition maxima and minima of the oscillation appear more distinct in time and make potential phase-dependent perception predictable.There is an ongoing debate about whether visual stimulation is suitable to entrain alpha oscillations. On the one hand, it has been argued that a series of light flashes results in transient event-related responses (ERPs superimposed on the ongoing EEG. On the other hand, it has been demonstrated that alpha oscillations become entrained to a series of light flashes if they are presented at a certain temporal regularity. This raises the question under which circumstances a sequence of light flashes causes entrainment, i.e. whether an arrhythmic stream of light flashes would also result in entrainment.Here, we measured detection rates in response to visual targets at two opposing stimulation phases during rhythmic and arrhythmic light stimulation. We introduce a new measure called ‘behavioral modulation depth’ to determine differences in perception. This measure is capable of correcting for inevitable artifacts that occur in visual detection tasks during visual stimulation. The physical concept of entrainment predicts that increased stimulation intensity should produce stronger entrainment. Thus, two experiments with medium (Experiment 1 and high (Experiment 2 stimulation intensity were performed. Data from the first experiment show that the behavioral modulation depth (alpha phase-dependent differences in detection threshold increases with increasing entrainment of alpha oscillations. Furthermore, individual alpha phase delays of entrained alpha oscillations determine the behavioral modulation depth: the largest behavioral modulation depth can be found if targets presented during the minimum of the entrained oscillation
Learning rates of least-square regularized regression with polynomial kernels
无
2009-01-01
This paper presents learning rates for the least-square regularized regression algorithms with polynomial kernels. The target is the error analysis for the regression problem in learning theory. A regularization scheme is given, which yields sharp learning rates. The rates depend on the dimension of polynomial space and polynomial reproducing kernel Hilbert space measured by covering numbers. Meanwhile, we also establish the direct approximation theorem by Bernstein-Durrmeyer operators in Lρ2X with Borel probability measure.
Regularity problem for quasilinear elliptic and parabolic systems
Koshelev, Alexander
1995-01-01
The smoothness of solutions for quasilinear systems is one of the most important problems in modern mathematical physics. This book deals with regular or strong solutions for general quasilinear second-order elliptic and parabolic systems. Applications in solid mechanics, hydrodynamics, elasticity and plasticity are described. The results presented are based on two main ideas: the universal iterative method, and explicit, sometimes sharp, coercivity estimates in weighted spaces. Readers are assumed to have a standard background in analysis and PDEs.
A generalized regular form for multivariable sliding mode control
Perruquetti W.
2001-01-01
Full Text Available The paper shows how to compute a diffeomorphic state space transformation in order to put the initial mutivariable nonlinear model into an appropriate regular form . This form is an extension of the one proposed by Lukyanov and Utkin [9], and constitutes a guidance for a “natural” choice of the sliding surface. Then stabilization is achieved via a sliding mode strategy. In order to overcome the chattering phenomenon, a new nonlinear gain is introduced.
A generalized regular form for multivariable sliding mode control
W. Perruquetti
2001-01-01
Full Text Available The paper shows how to compute a diffeomorphic state space transformation in order to put the initial mutivariable nonlinear model into an appropriate regular form. This form is an extension of the one proposed by Lukyanov and Utkin [9], and constitutes a guidance for a “natural” choice of the sliding surface. Then stabilization is achieved via a sliding mode strategy. In order to overcome the chattering phenomenon, a new nonlinear gain is introduced.
A generalized regular form for multivariable sliding mode control
Perruquetti, W.; Richard, J. P.; P. Borne
2001-01-01
The paper shows how to compute a diffeomorphic state space transformation in order to put the initial mutivariable nonlinear model into an appropriate regular form . This form is an extension of the one proposed by Lukyanov and Utkin [9], and constitutes a guidance for a “natural” choice of the sliding surface. Then stabilization is achieved via a sliding mode strategy. In order to overcome the chattering phenomenon, a new nonlinear gain is introduced.
An $\\varepsilon$-regularity Theorem For The Mean Curvature Flow
Han, Xiaoli; Sun, Jun
2011-01-01
In this paper, we will derive a small energy regularity theorem for the mean curvature flow of arbitrary dimension and codimension. It says that if the parabolic integral of $|A|^2$ around a point in space-time is small, then the mean curvature flow cannot develop singularity at this point. As an application, we can prove that the 2-dimensional Hausdorff measure of the singular set of the mean curvature flow from a surface to a Riemannian manifold must be zero.
Yosida-Moreau Regularization of Sweeping Processes with Unbounded Variation
Kunze, M.; Monteiro Marques, M. D. P.
1996-09-01
Lett↦C(t) be a Hausdorff-continuous multifunction with closed convex values in a Hilbert spaceHsuch thatC(t) has nonempty interior for allt. We show that the Yosida-Moreau regularizations of the sweeping process with moving setC(t), i.e., the solutions of[formula]are strongly pointwisely convergent asλ→0+to the solution of the corresponding sweeping process, formally written as[formula
Learning regularized LDA by clustering.
Pang, Yanwei; Wang, Shuang; Yuan, Yuan
2014-12-01
As a supervised dimensionality reduction technique, linear discriminant analysis has a serious overfitting problem when the number of training samples per class is small. The main reason is that the between- and within-class scatter matrices computed from the limited number of training samples deviate greatly from the underlying ones. To overcome the problem without increasing the number of training samples, we propose making use of the structure of the given training data to regularize the between- and within-class scatter matrices by between- and within-cluster scatter matrices, respectively, and simultaneously. The within- and between-cluster matrices are computed from unsupervised clustered data. The within-cluster scatter matrix contributes to encoding the possible variations in intraclasses and the between-cluster scatter matrix is useful for separating extra classes. The contributions are inversely proportional to the number of training samples per class. The advantages of the proposed method become more remarkable as the number of training samples per class decreases. Experimental results on the AR and Feret face databases demonstrate the effectiveness of the proposed method.
ENUMERATION OF REGULAR TRUTH FUNCTIONS
IN A PREVIOUS WORK, (Lockheed Missiles and Space Company, 6-90-61-26, Jan 1961) the classification problem of the linearly separable truth functions...was reduced to the enumeration of some special kind of linearly separable truth functions called canonical truth functions. A canonical truth ...function F of n variables has an important property: if x F and y x in the canonical partial order of Qn, then y F. Any truth function F of n
Senova, Suhan; Hosomi, Koichi; Gurruchaga, Jean-Marc; Gouello, Gaëtane; Ouerchefani, Naoufel; Beaugendre, Yara; Lepetit, Hélène; Lefaucheur, Jean-Pascal; Badin, Romina Aron; Dauguet, Julien; Jan, Caroline; Hantraye, Philippe; Brugières, Pierre; Palfi, Stéphane
2016-08-01
OBJECTIVE Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a well-established therapy for motor symptoms in patients with pharmacoresistant Parkinson's disease (PD). However, the procedure, which requires multimodal perioperative exploration such as imaging, electrophysiology, or clinical examination during macrostimulation to secure lead positioning, remains challenging because the STN cannot be reliably visualized using the gold standard, T2-weighted imaging (T2WI) at 1.5 T. Thus, there is a need to improve imaging tools to better visualize the STN, optimize DBS lead implantation, and enlarge DBS diffusion. METHODS Gradient-echo sequences such as those used in T2WI suffer from higher distortions at higher magnetic fields than spin-echo sequences. First, a spin-echo 3D SPACE (sampling perfection with application-optimized contrasts using different flip angle evolutions) FLAIR sequence at 3 T was designed, validated histologically in 2 nonhuman primates, and applied to 10 patients with PD; their data were clinically compared in a double-blind manner with those of a control group of 10 other patients with PD in whom STN targeting was performed using T2WI. RESULTS Overlap between the nonhuman primate STNs segmented on 3D-histological and on 3D-SPACE-FLAIR volumes was high for the 3 most anterior quarters (mean [± SD] Dice scores 0.73 ± 0.11, 0.74 ± 0.06, and 0.60 ± 0.09). STN limits determined by the 3D-SPACE-FLAIR sequence were more consistent with electrophysiological edges than those determined by T2WI (0.9 vs 1.4 mm, respectively). The imaging contrast of the STN on the 3D-SPACE-FLAIR sequence was 4 times higher (p SPACE-FLAIR-guided implantation than for those in whom T2WI was used (62.2% vs 43.6%, respectively; p SPACE-FLAIR sequence (p SPACE-FLAIR sequences at 3 T improved STN lead placement under stereotactic conditions, improved the clinical outcome of patients with PD, and increased the benefit/risk ratio of STN-DBS surgery.
Ideal regularization for learning kernels from labels.
Pan, Binbin; Lai, Jianhuang; Shen, Lixin
2014-08-01
In this paper, we propose a new form of regularization that is able to utilize the label information of a data set for learning kernels. The proposed regularization, referred to as ideal regularization, is a linear function of the kernel matrix to be learned. The ideal regularization allows us to develop efficient algorithms to exploit labels. Three applications of the ideal regularization are considered. Firstly, we use the ideal regularization to incorporate the labels into a standard kernel, making the resulting kernel more appropriate for learning tasks. Next, we employ the ideal regularization to learn a data-dependent kernel matrix from an initial kernel matrix (which contains prior similarity information, geometric structures, and labels of the data). Finally, we incorporate the ideal regularization to some state-of-the-art kernel learning problems. With this regularization, these learning problems can be formulated as simpler ones which permit more efficient solvers. Empirical results show that the ideal regularization exploits the labels effectively and efficiently.
Regularity extraction from non-adjacent sounds
Alexandra eBendixen
2012-05-01
Full Text Available The regular behavior of sound sources helps us to make sense of the auditory environment. Regular patterns may, for instance, convey information on the identity of a sound source (such as the acoustic signature of a train moving on the rails. Yet typically, this signature overlaps in time with signals emitted from other sound sources. It is generally assumed that auditory regularity extraction cannot operate upon this mixture of signals because it only finds regularities between adjacent sounds. In this view, the auditory environment would be grouped into separate entities by means of readily available acoustic cues such as separation in frequency and location. Regularity extraction processes would then operate upon the resulting groups. Our new experimental evidence challenges this view. We presented two interleaved sound sequences which overlapped in frequency range and shared all acoustic parameters. The sequences only differed in their underlying regular patterns. We inserted deviants into one of the sequences to probe whether the regularity was extracted. In the first experiment, we found that these deviants elicited the mismatch negativity (MMN component. Thus the auditory system was able to find the regularity between the non-adjacent sounds. Regularity extraction was not influenced by sequence cohesiveness as manipulated by the relative duration of tones and silent inter-tone-intervals. In the second experiment, we showed that a regularity connecting non-adjacent sounds was discovered only when the intervening sequence also contained a regular pattern, but not when the intervening sounds were randomly varying. This suggests that separate regular patterns are available to the auditory system as a cue for identifying signals coming from distinct sound sources. Thus auditory regularity extraction is not necessarily confined to a processing stage after initial sound grouping, but may precede grouping when other acoustic cues are unavailable.
Nondissipative Velocity and Pressure Regularizations for the ICON Model
Restelli, M.; Giorgetta, M.; Hundertmark, T.; Korn, P.; Reich, S.
2009-04-01
A challenging aspect in the numerical simulation of atmospheric and oceanic flows is the multiscale character of the problem both in space and time. The small spacial scales are generated by the turbulent energy and enstrophy cascades, and are usually dealt with by means of turbulence parametrizations, while the small temporal scales are governed by the propagation of acoustic and gravity waves, which are of little importance for the large scale dynamics and are often eliminated by means of a semi-implicit time discretization. We propose to treat both phenomena of subgrid turbulence and temporal scale separation in a unified way by means of nondissipative regularizations of the underlying model equations. More precisely, we discuss the use of two regularized equation sets: the velocity regularization, also know as Lagrangian averaged Navier-Stokes system, and the pressure regularization. Both regularizations are nondissipative since they do not enhance the dissipation of energy and enstrophy of the flow. The velocity regularization models the effects of the subgrid velocity fluctuations on the mean flow, it has thus been proposed as a turbulence parametrization and it has been found to yield promising results in ocean modeling [HHPW08]. In particular, the velocity regularization results in a higher variability of the numerical solution. The pressure regularization, discussed in [RWS07], modifies the propagation of acoustic and gravity waves so that the resulting system can be discretized explicitly in time with time steps analogous to those allowed by a semi-implicit method. Compared to semi-implicit time integrators, however, the pressure regularization takes fully into account the geostrophic balance of the flow. We discuss here the implementation of the velocity and pressure regularizations within the numerical framework of the ICON general circulation model (GCM) [BR05] for the case of the rotating shallow water system, showing how the original numerical
Regularity of spectral fractional Dirichlet and Neumann problems
Grubb, Gerd
2016-01-01
Consider the fractional powers and of the Dirichlet and Neumann realizations of a second-order strongly elliptic differential operator A on a smooth bounded subset Ω of . Recalling the results on complex powers and complex interpolation of domains of elliptic boundary value problems by Seeley...... in the 1970's, we demonstrate how they imply regularity properties in full scales of -Sobolev spaces and Hölder spaces, for the solutions of the associated equations. Extensions to nonsmooth situations for low values of s are derived by use of recent results on -calculus. We also include an overview...
Symplectic regularization of binary collisions in the circular N+2 Sitnikov problem
Jimenez-Perez, Hugo [IMCCE, Observatoire de Paris, 77 av. Denfert-Rochereau, 75014 Paris (France); Lacomba, Ernesto A, E-mail: jimenez@imcce.fr, E-mail: lace@xanum.uam.mx [Department of Mathematics, Universidad Autonoma Metropolitana, San Rafael Atlixco 186, C.P. 09430, Iztapalapa, Mexico City (Mexico)
2011-07-01
We present a brief overview of the regularizing transformations of the Kepler problem and we relate the Euler transformation with the symplectic structure of the phase space of the N-body problem. We show that any particular solution of the N-body problem where two bodies have rectilinear dynamics can be regularized by a linear symplectic transformation and the inclusion of the Euler transformation into the group of symplectic local diffeomorphisms over the phase space. As an application we regularize a particular configuration of the restricted circular N+2 body problem.
Reducing errors in the GRACE gravity solutions using regularization
Save, Himanshu; Bettadpur, Srinivas; Tapley, Byron D.
2012-09-01
solutions (RL04) from the Center for Space Research (CSR). Post-fit residual analysis shows that the regularized solutions fit the data to within the noise level of GRACE. A time series of filtered hydrological model is used to confirm that signal attenuation for basins in the Total Runoff Integrating Pathways (TRIP) database over 320 km radii is less than 1 cm equivalent water height RMS, which is within the noise level of GRACE.
Regularity of Semigroups via the Asymptotic Behaviour at Zero
Fackler, Stephan
2012-01-01
An interesting result by T. Kato and A. Pazy says that a contractive semigroup (T(t)) on a uniformly convex space X is holomorphic iff limsup_{t \\downarrow 0} ||T(t)-Id|| < 2. We study extensions of this result which are valid on arbitrary Banach spaces for semigroups which are not necessarily contractive. This allows us to prove a general extrapolation result for holomorphy of semigroups on interpolation spaces of exponent {\\theta} in (0,1). As application we characterize boundedness of the generator of a cosine family on a UMD-space by a zero-two law. Moreover, our methods can be applied to R-sectoriality: We obtain a characterization of maximal regularity by the behaviour of the semigroup at zero and show extrapolation results.
New Regularization Method in Electrical Impedance Tomography
侯卫东; 莫玉龙
2002-01-01
Image reconstruction in elecrical impedance tomography(EIT)is a highly ill-posed inverse problem,Regularization techniques must be used in order to solve the problem,In this paper,a new regularization method based on the spatial filtering theory is proposed.The new regularized reconstruction for EIT is independent of the estimation of impedance distribution,so it can be implemented more easily than the maxiumum a posteriori(MAP) method.The regularization level in our proposed method varies spatially so as to be suited to the correlation character of the object's impedance distribution.We implemented our regularization method with two dimensional computer simulations.The experimental results indicate that the quality of the reconstructed impedance images with the descibed regularization method based on spatial filtering theory is better than that with Tikhonov method.
Regularized Laplacian Estimation and Fast Eigenvector Approximation
Perry, Patrick O
2011-01-01
Recently, Mahoney and Orecchia demonstrated that popular diffusion-based procedures to compute a quick \\emph{approximation} to the first nontrivial eigenvector of a data graph Laplacian \\emph{exactly} solve certain regularized Semi-Definite Programs (SDPs). In this paper, we extend that result by providing a statistical interpretation of their approximation procedure. Our interpretation will be analogous to the manner in which $\\ell_2$-regularized or $\\ell_1$-regularized $\\ell_2$-regression (often called Ridge regression and Lasso regression, respectively) can be interpreted in terms of a Gaussian prior or a Laplace prior, respectively, on the coefficient vector of the regression problem. Our framework will imply that the solutions to the Mahoney-Orecchia regularized SDP can be interpreted as regularized estimates of the pseudoinverse of the graph Laplacian. Conversely, it will imply that the solution to this regularized estimation problem can be computed very quickly by running, e.g., the fast diffusion-base...
Total variation regularization with bounded linear variations
Makovetskii, Artyom; Voronin, Sergei; Kober, Vitaly
2016-09-01
One of the most known techniques for signal denoising is based on total variation regularization (TV regularization). A better understanding of TV regularization is necessary to provide a stronger mathematical justification for using TV minimization in signal processing. In this work, we deal with an intermediate case between one- and two-dimensional cases; that is, a discrete function to be processed is two-dimensional radially symmetric piecewise constant. For this case, the exact solution to the problem can be obtained as follows: first, calculate the average values over rings of the noisy function; second, calculate the shift values and their directions using closed formulae depending on a regularization parameter and structure of rings. Despite the TV regularization is effective for noise removal; it often destroys fine details and thin structures of images. In order to overcome this drawback, we use the TV regularization for signal denoising subject to linear signal variations are bounded.
Hidden Regular Variation: Detection and Estimation
Mitra, Abhimanyu
2010-01-01
Hidden regular variation defines a subfamily of distributions satisfying multivariate regular variation on $\\mathbb{E} = [0, \\infty]^d \\backslash \\{(0,0, ..., 0) \\} $ and models another regular variation on the sub-cone $\\mathbb{E}^{(2)} = \\mathbb{E} \\backslash \\cup_{i=1}^d \\mathbb{L}_i$, where $\\mathbb{L}_i$ is the $i$-th axis. We extend the concept of hidden regular variation to sub-cones of $\\mathbb{E}^{(2)}$ as well. We suggest a procedure of detecting the presence of hidden regular variation, and if it exists, propose a method of estimating the limit measure exploiting its semi-parametric structure. We exhibit examples where hidden regular variation yields better estimates of probabilities of risk sets.
A multiplicative regularization for force reconstruction
Aucejo, M.; De Smet, O.
2017-02-01
Additive regularizations, such as Tikhonov-like approaches, are certainly the most popular methods for reconstructing forces acting on a structure. These approaches require, however, the knowledge of a regularization parameter, that can be numerically computed using specific procedures. Unfortunately, these procedures are generally computationally intensive. For this particular reason, it could be of primary interest to propose a method able to proceed without defining any regularization parameter beforehand. In this paper, a multiplicative regularization is introduced for this purpose. By construction, the regularized solution has to be calculated in an iterative manner. In doing so, the amount of regularization is automatically adjusted throughout the resolution process. Validations using synthetic and experimental data highlight the ability of the proposed approach in providing consistent reconstructions.
Regular Disjunction-Free Default Theories
Xi-ShunZhao
2004-01-01
In this paper, the class of regular disjunction-free default theories is introduced and investigated. A transformation from regular default theories to normal default theories is established. The initial theory and the transformed theory have the same extensions when restricted to old variables. Hence, regular default theories enjoy some similar properties (e.g., existence of extensions, semi-monotonicity) as normal default theories. Then, a new algorithm for credulous reasoning of regular theories is developed. This algorithm runs in a time not more than O(1.45n), where n is the number of defaults. In case of regular prerequisite-free or semi-2CNF default theories, the credulous reasoning can be solved in polynomial time. However, credulous reasoning for semi-Horn default theories is shown to be NP-complete although it is tractable for Horn default theories. Moreover, skeptical reasoning for regular unary default theories is co-NP-complete.
Regular Disjunction-Free Default Theories
Xi-Shun Zhao
2004-01-01
In this paper, the class of regular disjunction-free default theories is introduced and investigated.A transformation from regular default theories to normal default theories is established. The initial theory and the transformed theory have the same extensions when restricted to old variables. Hence, regular default theories enjoy some similar properties (e.g., existence of extensions, semi-monotonicity) as normal default theories. Then,a new algorithm for credulous reasoning of regular theories is developed. This algorithm runs in a time not more than O(1.45n), where n is the number of defaults. In case of regular prerequisite-free or semi-2CNF default theories, the credulous reasoning can be solved in polynomial time. However, credulous reasoning for semi-Horn default theories is shown to be NP-complete although it is tractable for Horn default theories. Moreover, skeptical reasoning for regular unary default theories is co-NP-complete.
A low-cost multichannel wireless neural stimulation system for freely roaming animals
Alam, Monzurul; Chen, Xi; Fernandez, Eduardo
2013-12-01
Objectives. Electrical stimulation of nerve tissue and recording of neural activity are the basis of many therapies and neural prostheses. Conventional stimulation systems have a number of practical limitations, especially in experiments involving freely roaming subjects. Our main objective was to develop a modular, versatile and inexpensive multichannel wireless system able to overcome some of these constraints. Approach. We have designed and implemented a new multichannel wireless neural stimulator based on commercial components. The system is small (2 cm × 4 cm × 0.5 cm) and light in weight (9 g) which allows it to be easily carried in a small backpack. To test and validate the performance and reliability of the whole system we conducted several bench tests and in vivo experiments. Main results. The performance and accuracy of the stimulator were comparable to commercial threaded systems. Stimulation sequences can be constructed on-the-fly with 251 selectable current levels (from 0 to 250 µA) with 1 µA step resolution. The pulse widths and intervals can be as long as 65 ms in 2 µs time resolution. The system covers approximately 10 m of transmission range in a regular laboratory environment and 100 m in free space (line of sight). Furthermore it provides great flexibility for experiments since it allows full control of the stimulator and the stimulation parameters in real time. When there is no stimulation, the device automatically goes into low-power sleep mode to preserve battery power. Significance. We introduce the design of a powerful multichannel wireless stimulator assembled from commercial components. Key features of the system are their reliability, robustness and small size. The system has a flexible design that can be modified straightforwardly to tailor it to any specific experimental need. Furthermore it can be effortlessly adapted for use with any kind of multielectrode arrays.
Mining, habitats lead space architecture work
David Nixon
2013-01-01
Nixon narrates how space mining habitats lead space architecture work. NASA's current focus on an asteroid rendezvous mission as human space exploration's next big goal has begun to stimulate ideas from the space community at large...
Regularity effect in prospective memory during aging
Geoffrey Blondelle
2016-10-01
Full Text Available Background: Regularity effect can affect performance in prospective memory (PM, but little is known on the cognitive processes linked to this effect. Moreover, its impacts with regard to aging remain unknown. To our knowledge, this study is the first to examine regularity effect in PM in a lifespan perspective, with a sample of young, intermediate, and older adults. Objective and design: Our study examined the regularity effect in PM in three groups of participants: 28 young adults (18–30, 16 intermediate adults (40–55, and 25 older adults (65–80. The task, adapted from the Virtual Week, was designed to manipulate the regularity of the various activities of daily life that were to be recalled (regular repeated activities vs. irregular non-repeated activities. We examine the role of several cognitive functions including certain dimensions of executive functions (planning, inhibition, shifting, and binding, short-term memory, and retrospective episodic memory to identify those involved in PM, according to regularity and age. Results: A mixed-design ANOVA showed a main effect of task regularity and an interaction between age and regularity: an age-related difference in PM performances was found for irregular activities (older < young, but not for regular activities. All participants recalled more regular activities than irregular ones with no age effect. It appeared that recalling of regular activities only involved planning for both intermediate and older adults, while recalling of irregular ones were linked to planning, inhibition, short-term memory, binding, and retrospective episodic memory. Conclusion: Taken together, our data suggest that planning capacities seem to play a major role in remembering to perform intended actions with advancing age. Furthermore, the age-PM-paradox may be attenuated when the experimental design is adapted by implementing a familiar context through the use of activities of daily living. The clinical
Ambiguities in Pauli-Villars regularization
Kleiss, Ronald H P
2014-01-01
We investigate regularization of scalar one-loop integrals in the Pauli- Villars subtraction scheme. The results depend on the number of sub- tractions, in particular the finite terms that survive after the diver- gences have been absorbed by renormalization. Therefore the process of Pauli-Villars regularization is ambiguous. We discuss how these am- biguities may be resolved by applying an asymptotically large number of subtractions, which results in a regularization that is automatically valid in any number of dimensions.
Regularized brain reading with shrinkage and smoothing
Wehbe, Leila; Ramdas, Aaditya; Steorts, Rebecca C.; Shalizi, Cosma Rohilla
2014-01-01
Functional neuroimaging measures how the brain responds to complex stimuli. However, sample sizes are modest, noise is substantial, and stimuli are high dimensional. Hence, direct estimates are inherently imprecise and call for regularization. We compare a suite of approaches which regularize via shrinkage: ridge regression, the elastic net (a generalization of ridge regression and the lasso), and a hierarchical Bayesian model based on small area estimation (SAE). We contrast regularization w...
Branch Processes of Regular Magnetic Monopole
MO Shu-Fan; REN Ji-Rong; ZHU Tao
2009-01-01
In this paper, by making use of Duan's topological current theory, the branch process of regular magnetic monopoles is discussed in detail Regular magnetic monopoles are found generating or annihilating at the limit point and encountering, splitting, or merging at the bifurcation point and the degenerate point systematically of the vector order parameter field φ(x).Furthermore, it is also shown that when regular magnetic monopoles split or merge at the degenerate point of field function φ, the total topological charges of the regular magnetic monopoles axe still unchanged.
Iterative Regularization with Minimum-Residual Methods
Jensen, Toke Koldborg; Hansen, Per Christian
2007-01-01
We study the regularization properties of iterative minimum-residual methods applied to discrete ill-posed problems. In these methods, the projection onto the underlying Krylov subspace acts as a regularizer, and the emphasis of this work is on the role played by the basis vectors of these Krylov...... subspaces. We provide a combination of theory and numerical examples, and our analysis confirms the experience that MINRES and MR-II can work as general regularization methods. We also demonstrate theoretically and experimentally that the same is not true, in general, for GMRES and RRGMRES their success...... as regularization methods is highly problem dependent....
Iterative regularization with minimum-residual methods
Jensen, Toke Koldborg; Hansen, Per Christian
2006-01-01
We study the regularization properties of iterative minimum-residual methods applied to discrete ill-posed problems. In these methods, the projection onto the underlying Krylov subspace acts as a regularizer, and the emphasis of this work is on the role played by the basis vectors of these Krylov...... subspaces. We provide a combination of theory and numerical examples, and our analysis confirms the experience that MINRES and MR-II can work as general regularization methods. We also demonstrate theoretically and experimentally that the same is not true, in general, for GMRES and RRGMRES - their success...... as regularization methods is highly problem dependent....
Ideal-comparability over Regular Rings
Huan Yin CHEN; Miao Sen CHEN
2006-01-01
We introduce the concept of ideal-comparability condition for regular rings. Let I be an ideal of a regular ring R. If R satisfies the Ⅰ-comparability condition, then R is one-sided unit-regular if and only if so is R/I. Also, we show that a regular ring R satisfies the general comparability if and only if the following hold: (1) R/I satisfies the general comparability; (2) R satisfies the general Ⅰ-comparability condition; (3) The natural map B(R) → B(R/I) is surjective.
Local and Nonlocal Regularization to Image Interpolation
Yi Zhan
2014-01-01
Full Text Available This paper presents an image interpolation model with local and nonlocal regularization. A nonlocal bounded variation (BV regularizer is formulated by an exponential function including gradient. It acts as the Perona-Malik equation. Thus our nonlocal BV regularizer possesses the properties of the anisotropic diffusion equation and nonlocal functional. The local total variation (TV regularizer dissipates image energy along the orthogonal direction to the gradient to avoid blurring image edges. The derived model efficiently reconstructs the real image, leading to a natural interpolation which reduces blurring and staircase artifacts. We present experimental results that prove the potential and efficacy of the method.
Regularization and error assignment to unfolded distributions
Zech, Gunter
2011-01-01
The commonly used approach to present unfolded data only in graphical formwith the diagonal error depending on the regularization strength is unsatisfac-tory. It does not permit the adjustment of parameters of theories, the exclusionof theories that are admitted by the observed data and does not allow the com-bination of data from different experiments. We propose fixing the regulariza-tion strength by a p-value criterion, indicating the experimental uncertaintiesindependent of the regularization and publishing the unfolded data in additionwithout regularization. These considerations are illustrated with three differentunfolding and smoothing approaches applied to a toy example.
Bit-coded regular expression parsing
Nielsen, Lasse; Henglein, Fritz
2011-01-01
Regular expression parsing is the problem of producing a parse tree of a string for a given regular expression. We show that a compact bit representation of a parse tree can be produced efficiently, in time linear in the product of input string size and regular expression size, by simplifying...... the DFA-based parsing algorithm due to Dub ´e and Feeley to emit the bits of the bit representation without explicitly materializing the parse tree itself. We furthermore show that Frisch and Cardelli’s greedy regular expression parsing algorithm can be straightforwardly modified to produce bit codings...
The regularity of quotient paratopological groups
Banakh, Taras
2010-01-01
Let $H$ be a closed subgroup of a regular abelian paratopological group $G$. The group reflexion $G^\\flat$ of $G$ is the group $G$ endowed with the strongest group topology, weaker that the original topology of $G$. We show that the quotient $G/H$ is Hausdorff (and regular) if $H$ is closed (and locally compact) in $G^\\flat$. On the other hand, we construct an example of a regular abelian paratopological group $G$ containing a closed discrete subgroup $H$ such that the quotient $G/H$ is Hausdorff but not regular.
Continuum regularization of quantum field theory
Bern, Z.
1986-04-01
Possible nonperturbative continuum regularization schemes for quantum field theory are discussed which are based upon the Langevin equation of Parisi and Wu. Breit, Gupta and Zaks made the first proposal for new gauge invariant nonperturbative regularization. The scheme is based on smearing in the ''fifth-time'' of the Langevin equation. An analysis of their stochastic regularization scheme for the case of scalar electrodynamics with the standard covariant gauge fixing is given. Their scheme is shown to preserve the masslessness of the photon and the tensor structure of the photon vacuum polarization at the one-loop level. Although stochastic regularization is viable in one-loop electrodynamics, two difficulties arise which, in general, ruins the scheme. One problem is that the superficial quadratic divergences force a bottomless action for the noise. Another difficulty is that stochastic regularization by fifth-time smearing is incompatible with Zwanziger's gauge fixing, which is the only known nonperturbaive covariant gauge fixing for nonabelian gauge theories. Finally, a successful covariant derivative scheme is discussed which avoids the difficulties encountered with the earlier stochastic regularization by fifth-time smearing. For QCD the regularized formulation is manifestly Lorentz invariant, gauge invariant, ghost free and finite to all orders. A vanishing gluon mass is explicitly verified at one loop. The method is designed to respect relevant symmetries, and is expected to provide suitable regularization for any theory of interest. Hopefully, the scheme will lend itself to nonperturbative analysis. 44 refs., 16 figs.
Adaptive regularization of noisy linear inverse problems
Hansen, Lars Kai; Madsen, Kristoffer Hougaard; Lehn-Schiøler, Tue
2006-01-01
In the Bayesian modeling framework there is a close relation between regularization and the prior distribution over parameters. For prior distributions in the exponential family, we show that the optimal hyper-parameter, i.e., the optimal strength of regularization, satisfies a simple relation: T...
12 CFR 725.3 - Regular membership.
2010-01-01
... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Regular membership. 725.3 Section 725.3 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS NATIONAL CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.3 Regular membership. (a) A natural person...
Fast and compact regular expression matching
Bille, Philip; Farach-Colton, Martin
2008-01-01
We study 4 problems in string matching, namely, regular expression matching, approximate regular expression matching, string edit distance, and subsequence indexing, on a standard word RAM model of computation that allows logarithmic-sized words to be manipulated in constant time. We show how...
Regularity of harmonic maps with the potential
CHU; Yuming
2006-01-01
The aim of this work is to prove the partial regularity of the harmonic maps with potential. The main difficulty caused by the potential is how to find the equation satisfied by the scaling function. Under the assumption on the potential we can obtain the equation, however, for a general potential, even if it is smooth, the partial regularity is still open.
On the Equivalence of Regularization Schemes
YANG Ji-Feng
2002-01-01
We illustrate via the sunset diagram that dimensional regularization ‘deforms' the nonlocal contentsof multi-loop diagrams with its equivalence to cutoff regularization scheme recovered only after sub-divergence wassubtracted. Then we employed a differential equation approach for calculating loop diagrams to verify that dimensionalare argued especially in nonperturbativc perspective.
Regular Event Structures and Finite Petri Nets
Nielsen, M.; Thiagarajan, P.S.
2002-01-01
We present the notion of regular event structures and conjecture that they correspond exactly to finite 1-safe Petri nets. We show that the conjecture holds for the conflict-free case. Even in this restricted setting, the proof is non-trivial and involves a natural subclass of regular event...
Regularity Re-Revisited: Modality Matters
Tsapkini, Kyrana; Jarema, Gonia; Kehayia, Eva
2004-01-01
The issue of regular-irregular past tense formation was examined in a cross-modal lexical decision task in Modern Greek, a language where the orthographic and phonological overlap between present and past tense stems is the same for both regular and irregular verbs. The experiment described here is a follow-up study of previous visual lexical…
Regularization algorithms based on total least squares
Hansen, Per Christian; O'Leary, Dianne P.
1996-01-01
Discretizations of inverse problems lead to systems of linear equations with a highly ill-conditioned coefficient matrix, and in order to compute stable solutions to these systems it is necessary to apply regularization methods. Classical regularization methods, such as Tikhonov's method or trunc...
A regularized stationary mean-field game
Yang, Xianjin
2016-04-19
In the thesis, we discuss the existence and numerical approximations of solutions of a regularized mean-field game with a low-order regularization. In the first part, we prove a priori estimates and use the continuation method to obtain the existence of a solution with a positive density. Finally, we introduce the monotone flow method and solve the system numerically.
郑伟; 许厚泽; 钟敏; 员美娟; 周旭华
2011-01-01
The GOCE Earth's gravitational field complete up to degree and order 250 is recovered based on the time-space-wise-approach associated with Kaula regularization in order to study the influences of satellite gravity gradiometry on the accuracy of medium-high frequency Earth' s gravitational field recovery. The simulated results show: Firstly, the time-space-wise-approach is an effective way to accurately and rapidly determine the high-degree Earth's gravitational field;Secondly, the Kaula regularization is one of the key processes to reduce ill condition of normal matrix; Thirdly, the large-scale linear system of equations is solved quickly using the improved pre-conditioned conjugate-gradient iterative approach, and the computing speed can be improved at least l000 times as compared to the direct least-squares approach; Fourthly, at the degree 250 ,cumulative geoid height and gravity anomaly errors are 9. 295 cm and 0. 204 mGal with orbital error I cm and gravity gradient error 3XIO-12/s2 , respectively. Finally, the complementarity of high-accuracy and high-resolution Earth' s gravitational field recovery between international GRACE and GOCE missions is demonstrated.%为了研究卫星重力梯度技术对中高频地球重力场反演精度的影响,本文基于时空域混合法,利用Kaula正则化反演了250阶GOCE地球重力场.模拟结果表明:第一,时空域混合法是精确和快速求解高阶地球重力场的有效方法;第二,Kaula正则化是降低正规阵病态性的重要方法;第三,基于改进的预处理共轭梯度迭代法可快速求解大型线性方程组,计算速度较直接最小二乘法至少提高1000倍;第四,基于卫星轨道误差1 cm和卫星重力梯度误差3×10-12/s2,在250阶处反演累计大地水准面和重力异常的精度分别为9.295 cm和0.204 mGal.第五,论证了基于国际GRACE和GOCE卫星计划反演高精度和高空间分辨率地球重力场的互补性.
Nonlocal Regularized Algebraic Reconstruction Techniques for MRI: An Experimental Study
Xin Li
2013-01-01
Full Text Available We attempt to revitalize researchers' interest in algebraic reconstruction techniques (ART by expanding their capabilities and demonstrating their potential in speeding up the process of MRI acquisition. Using a continuous-to-discrete model, we experimentally study the application of ART into MRI reconstruction which unifies previous nonuniform-fast-Fourier-transform- (NUFFT- based and gridding-based approaches. Under the framework of ART, we advocate the use of nonlocal regularization techniques which are leveraged from our previous research on modeling photographic images. It is experimentally shown that nonlocal regularization ART (NR-ART can often outperform their local counterparts in terms of both subjective and objective qualities of reconstructed images. On one real-world k-space data set, we find that nonlocal regularization can achieve satisfactory reconstruction from as few as one-third of samples. We also address an issue related to image reconstruction from real-world k-space data but overlooked in the open literature: the consistency of reconstructed images across different resolutions. A resolution-consistent extension of NR-ART is developed and shown to effectively suppress the artifacts arising from frequency extrapolation. Both source codes and experimental results of this work are made fully reproducible.
Chistyakov, Vyacheslav
2015-01-01
Aimed toward researchers and graduate students familiar with elements of functional analysis, linear algebra, and general topology; this book contains a general study of modulars, modular spaces, and metric modular spaces. Modulars may be thought of as generalized velocity fields and serve two important purposes: generate metric spaces in a unified manner and provide a weaker convergence, the modular convergence, whose topology is non-metrizable in general. Metric modular spaces are extensions of metric spaces, metric linear spaces, and classical modular linear spaces. The topics covered include the classification of modulars, metrizability of modular spaces, modular transforms and duality between modular spaces, metric and modular topologies. Applications illustrated in this book include: the description of superposition operators acting in modular spaces, the existence of regular selections of set-valued mappings, new interpretations of spaces of Lipschitzian and absolutely continuous mappings, the existe...
Nasimi, Ali; Rees, Adrian
2010-12-01
The spike discharge regularity may be important in the processing of information in the auditory pathway. It has already been shown that many cells in the central nucleus of the inferior colliculus fire regularly in response to monaural stimulation by the best frequency tones. The aim of this study was to find how the regularity of units was affected by adding ipsilateral tone, and how interaural intensity difference sensitivity is related to regularity. Single unit recordings were performed from 66 units in the inferior colliculus of the anaesthetized guinea pig in response to the best frequency tone. Regularity of firing was measured by calculating the coefficient of variation as a function of time of a unit's response. There was a positive correlation between coefficient of variation and interaural intensity difference sensitivity, indicating that highly regular units had very weak and irregular units had strong interaural intensity difference sensitivity responses. Three effects of binaural interaction on the sustained regularity were observed: constant coefficient of variation despite change in rate (66% of the units), negative (20%) and positive (13%) rate-CV relationships. A negative rate-coefficient of variation relationship was the dominant pattern of binaural interaction on the onset regularity.
Minimal regular 2-graphs and applications
FAN; Hongbing; LIU; Guizhen; LIU; Jiping
2006-01-01
A 2-graph is a hypergraph with edge sizes of at most two. A regular 2-graph is said to be minimal if it does not contain a proper regular factor. Let f2(n) be the maximum value of degrees over all minimal regular 2-graphs of n vertices. In this paper, we provide a structure property of minimal regular 2-graphs, and consequently, prove that f2(n) = n+3-i/3where 1 ≤i≤6, i=n (mod 6) andn≥ 7, which solves a conjecture posed by Fan, Liu, Wu and Wong. As applications in graph theory, we are able to characterize unfactorable regular graphs and provide the best possible factor existence theorem on degree conditions. Moreover, f2(n) and the minimal 2-graphs can be used in the universal switch box designs, which originally motivated this study.
Regular Expression Matching and Operational Semantics
Rathnayake, Asiri; 10.4204/EPTCS.62.3
2011-01-01
Many programming languages and tools, ranging from grep to the Java String library, contain regular expression matchers. Rather than first translating a regular expression into a deterministic finite automaton, such implementations typically match the regular expression on the fly. Thus they can be seen as virtual machines interpreting the regular expression much as if it were a program with some non-deterministic constructs such as the Kleene star. We formalize this implementation technique for regular expression matching using operational semantics. Specifically, we derive a series of abstract machines, moving from the abstract definition of matching to increasingly realistic machines. First a continuation is added to the operational semantics to describe what remains to be matched after the current expression. Next, we represent the expression as a data structure using pointers, which enables redundant searches to be eliminated via testing for pointer equality. From there, we arrive both at Thompson's lock...
A linear functional strategy for regularized ranking.
Kriukova, Galyna; Panasiuk, Oleksandra; Pereverzyev, Sergei V; Tkachenko, Pavlo
2016-01-01
Regularization schemes are frequently used for performing ranking tasks. This topic has been intensively studied in recent years. However, to be effective a regularization scheme should be equipped with a suitable strategy for choosing a regularization parameter. In the present study we discuss an approach, which is based on the idea of a linear combination of regularized rankers corresponding to different values of the regularization parameter. The coefficients of the linear combination are estimated by means of the so-called linear functional strategy. We provide a theoretical justification of the proposed approach and illustrate them by numerical experiments. Some of them are related with ranking the risk of nocturnal hypoglycemia of diabetes patients.
On regularizations of the Dirac delta distribution
Hosseini, Bamdad; Nigam, Nilima; Stockie, John M.
2016-01-01
In this article we consider regularizations of the Dirac delta distribution with applications to prototypical elliptic and hyperbolic partial differential equations (PDEs). We study the convergence of a sequence of distributions SH to a singular term S as a parameter H (associated with the support size of SH) shrinks to zero. We characterize this convergence in both the weak-* topology of distributions and a weighted Sobolev norm. These notions motivate a framework for constructing regularizations of the delta distribution that includes a large class of existing methods in the literature. This framework allows different regularizations to be compared. The convergence of solutions of PDEs with these regularized source terms is then studied in various topologies such as pointwise convergence on a deleted neighborhood and weighted Sobolev norms. We also examine the lack of symmetry in tensor product regularizations and effects of dissipative error in hyperbolic problems.
A concentration inequality for product spaces
Dodos, Pandelis; Kanellopoulos, Vassilis; Tyros, Konstantinos
2014-01-01
We prove a concentration inequality which asserts that, under some mild regularity conditions, every random variable defined on the product of sufficiently many probability spaces exhibits pseudorandom behavior.
Elementary Particle Spectroscopy in Regular Solid Rewrite
Trell, Erik
2008-10-01
The Nilpotent Universal Computer Rewrite System (NUCRS) has operationalized the radical ontological dilemma of Nothing at All versus Anything at All down to the ground recursive syntax and principal mathematical realisation of this categorical dichotomy as such and so governing all its sui generis modalities, leading to fulfilment of their individual terms and compass when the respective choice sequence operations are brought to closure. Focussing on the general grammar, NUCRS by pure logic and its algebraic notations hence bootstraps Quantum Mechanics, aware that it "is the likely keystone of a fundamental computational foundation" also for e.g. physics, molecular biology and neuroscience. The present work deals with classical geometry where morphology is the modality, and ventures that the ancient regular solids are its specific rewrite system, in effect extensively anticipating the detailed elementary particle spectroscopy, and further on to essential structures at large both over the inorganic and organic realms. The geodetic antipode to Nothing is extension, with natural eigenvector the endless straight line which when deployed according to the NUCRS as well as Plotelemeian topographic prescriptions forms a real three-dimensional eigenspace with cubical eigenelements where observed quark-skewed quantum-chromodynamical particle events self-generate as an Aristotelean phase transition between the straight and round extremes of absolute endlessness under the symmetry- and gauge-preserving, canonical coset decomposition SO(3)×O(5) of Lie algebra SU(3). The cubical eigen-space and eigen-elements are the parental state and frame, and the other solids are a range of transition matrix elements and portions adapting to the spherical root vector symmetries and so reproducibly reproducing the elementary particle spectroscopy, including a modular, truncated octahedron nano-composition of the Electron which piecemeal enter into molecular structures or compressed to each
A two-way regularization method for MEG source reconstruction
Tian, Tian Siva
2012-09-01
The MEG inverse problem refers to the reconstruction of the neural activity of the brain from magnetoencephalography (MEG) measurements. We propose a two-way regularization (TWR) method to solve the MEG inverse problem under the assumptions that only a small number of locations in space are responsible for the measured signals (focality), and each source time course is smooth in time (smoothness). The focality and smoothness of the reconstructed signals are ensured respectively by imposing a sparsity-inducing penalty and a roughness penalty in the data fitting criterion. A two-stage algorithm is developed for fast computation, where a raw estimate of the source time course is obtained in the first stage and then refined in the second stage by the two-way regularization. The proposed method is shown to be effective on both synthetic and real-world examples. © Institute of Mathematical Statistics, 2012.
Consistency Relations for an Implicit n-dimensional Regularization Scheme
Scarpelli, A P B; Nemes, M C
2001-01-01
We extend an implicit regularization scheme to be applicable in the $n$-dimensional space-time. Within this scheme divergences involving parity violating objects can be consistently treated without recoursing to dimensional continuation. Special attention is paid to differences between integrals of the same degree of divergence, typical of one loop calculations, which are in principle undetermined. We show how to use symmetries in order to fix these quantities consistently. We illustrate with examples in which regularization plays a delicate role in order to both corroborate and elucidate the results in the literature for the case of CPT violation in extended $QED_4$, topological mass generation in 3-dimensional gauge theories and the Schwinger Model and its chiral version.
A theoretical foundation for multi-scale regular vegetation patterns.
Tarnita, Corina E; Bonachela, Juan A; Sheffer, Efrat; Guyton, Jennifer A; Coverdale, Tyler C; Long, Ryan A; Pringle, Robert M
2017-01-18
Self-organized regular vegetation patterns are widespread and thought to mediate ecosystem functions such as productivity and robustness, but the mechanisms underlying their origin and maintenance remain disputed. Particularly controversial are landscapes of overdispersed (evenly spaced) elements, such as North American Mima mounds, Brazilian murundus, South African heuweltjies, and, famously, Namibian fairy circles. Two competing hypotheses are currently debated. On the one hand, models of scale-dependent feedbacks, whereby plants facilitate neighbours while competing with distant individuals, can reproduce various regular patterns identified in satellite imagery. Owing to deep theoretical roots and apparent generality, scale-dependent feedbacks are widely viewed as a unifying and near-universal principle of regular-pattern formation despite scant empirical evidence. On the other hand, many overdispersed vegetation patterns worldwide have been attributed to subterranean ecosystem engineers such as termites, ants, and rodents. Although potentially consistent with territorial competition, this interpretation has been challenged theoretically and empirically and (unlike scale-dependent feedbacks) lacks a unifying dynamical theory, fuelling scepticism about its plausibility and generality. Here we provide a general theoretical foundation for self-organization of social-insect colonies, validated using data from four continents, which demonstrates that intraspecific competition between territorial animals can generate the large-scale hexagonal regularity of these patterns. However, this mechanism is not mutually exclusive with scale-dependent feedbacks. Using Namib Desert fairy circles as a case study, we present field data showing that these landscapes exhibit multi-scale patterning-previously undocumented in this system-that cannot be explained by either mechanism in isolation. These multi-scale patterns and other emergent properties, such as enhanced resistance to
Boesveldt, N.F.
2016-01-01
WISES are social enterprises that work with people marginalized from the regular labour market, including people with severe handicaps, with disabilities and those who suffer addiction and homelessness. WISES offer an alternative to regular social programs: they breach social exclusion and stimulate working within a regular business environment. De Omslag has set up the Amsterdam Platform of social firms in order to stimulate and support WISES at the local level by exchanging knowledge, exper...
Multiple graph regularized protein domain ranking
Wang, Jim Jing-Yan
2012-11-19
Background: Protein domain ranking is a fundamental task in structural biology. Most protein domain ranking methods rely on the pairwise comparison of protein domains while neglecting the global manifold structure of the protein domain database. Recently, graph regularized ranking that exploits the global structure of the graph defined by the pairwise similarities has been proposed. However, the existing graph regularized ranking methods are very sensitive to the choice of the graph model and parameters, and this remains a difficult problem for most of the protein domain ranking methods.Results: To tackle this problem, we have developed the Multiple Graph regularized Ranking algorithm, MultiG-Rank. Instead of using a single graph to regularize the ranking scores, MultiG-Rank approximates the intrinsic manifold of protein domain distribution by combining multiple initial graphs for the regularization. Graph weights are learned with ranking scores jointly and automatically, by alternately minimizing an objective function in an iterative algorithm. Experimental results on a subset of the ASTRAL SCOP protein domain database demonstrate that MultiG-Rank achieves a better ranking performance than single graph regularized ranking methods and pairwise similarity based ranking methods.Conclusion: The problem of graph model and parameter selection in graph regularized protein domain ranking can be solved effectively by combining multiple graphs. This aspect of generalization introduces a new frontier in applying multiple graphs to solving protein domain ranking applications. 2012 Wang et al; licensee BioMed Central Ltd.
Temporal pattern of stimulation modulates reflex bladder activation by pudendal nerve stimulation.
McGee, Meredith J; Grill, Warren M
2016-11-01
Reflex bladder activation and inhibition by electrical stimulation of pudendal nerve (PN) afferents is a promising approach to restore control of bladder function in persons with lower urinary tract dysfunction caused by disease or injury. The objective of this work was to determine whether bladder activation evoked by pudendal afferent stimulation was dependent on the temporal pattern of stimulation, and whether specific temporal patterns of stimulation produced larger bladder contractions than constant frequency stimulation. The mean and maximum contraction pressures evoked by different temporal patterns of stimulation of the dorsal genital branch of the pudendal nerve were measured under isovolumetric conditions in α-chloralose anesthetized cats. A computational model of the spinal neural network mediating the pudendo-vesical reflex was used to understand the mechanisms of different bladder responses to patterned stimulation. The pattern of stimulation significantly affected the magnitude of evoked bladder contractions; several temporal patterns were as effective as regular stimulation, but no pattern evoked larger bladder contractions. Random patterns and patterns with pauses, burst-like activity, or high frequency components evoked significantly smaller bladder contractions, supporting the use of regular frequency stimulation in the development of neural prosthetic approaches for bladder control. These results reveal that the bladder response to pudendal afferent stimulation is dependent on the pattern, as well as the frequency, of stimulation. The computational model revealed that the effects of patterned pudendal afferent stimulation were determined by the dynamic properties of excitatory and inhibitory interneurons in the lumbosacral spinal cord. Neurourol. Urodynam. 35:882-887, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
J-regular rings with injectivities
Shen, Liang
2010-01-01
A ring $R$ is called a J-regular ring if R/J(R) is von Neumann regular, where J(R) is the Jacobson radical of R. It is proved that if R is J-regular, then (i) R is right n-injective if and only if every homomorphism from an $n$-generated small right ideal of $R$ to $R_{R}$ can be extended to one from $R_{R}$ to $R_{R}$; (ii) R is right FP-injective if and only if R is right (J, R)-FP-injective. Some known results are improved.
Low power implementation of datapath using regularity
LAI Li-ya; LIU Peng
2005-01-01
Datapath accounts for a considerable part of power consumption in VLSI circuit design. This paper presents a method for physical implementation of datapath to achieve low power consumption. Regularity is a characteristic of datapath and the key of the proposed method, where synthesis is tightly combined with placement to make full use of regularity, so that low power consumption is achieved. In This paper, a new concept of Synthesis In Relative Placement (SIRP) is given to deal with the semi-regularity in some datapath. Experimental results of a sample circuit validated the proposed method.
REGULARIZATION OF SINGULAR SYSTEMS BY OUTPUT FEEDBACK
De-lin Chu; Da-yong Cai
2000-01-01
Problem of regularization of a singular system by derivative and proportional output feedback is studied. Necessary and sufficient conditions are obtained under which a singular system can be regularized into a closed-loop system that is regular and of index at most one. The reduced form is given that can easily explore the system properties as well as the feedback to be determined. The main results of the present paper are based on orthogonal transformations. Therefore, they can be implemented by numerically stable ways.
Iterative Regularization with Minimum-Residual Methods
Jensen, Toke Koldborg; Hansen, Per Christian
2007-01-01
We study the regularization properties of iterative minimum-residual methods applied to discrete ill-posed problems. In these methods, the projection onto the underlying Krylov subspace acts as a regularizer, and the emphasis of this work is on the role played by the basis vectors of these Krylov...... subspaces. We provide a combination of theory and numerical examples, and our analysis confirms the experience that MINRES and MR-II can work as general regularization methods. We also demonstrate theoretically and experimentally that the same is not true, in general, for GMRES and RRGMRES their success...
MULTI-PARAMETER TIKHONOV REGULARIZATION FOR LINEAR ILL-POSED OPERATOR EQUATIONS
Zhongying Chen; Yao Lu; Yuesheng Xu; Hongqi Yang
2008-01-01
We consider solving linear ill-posed operator equations.Based on a multi-scale decomposition for the solution space,we propose a multi-parameter regularization for solving the equations.We establish weak and strong convergence theorems for the multi-parameter regularization solution.In particular,based on the eigenfunction decomposition,we develop a posteriori choice strategy for multi-parameters which gives a regularization solution with the optimal error bound.Several practical choices of multi-parameters are proposed.We also present numerical experiments to demonstrate the outperformance of the multiparameter regularization over the single parameter regularization.Mathematics subject classification:47A52.
A multiresolution method for solving the Poisson equation using high order regularization
Hejlesen, Mads Mølholm; Walther, Jens Honore
2016-01-01
We present a novel high order multiresolution Poisson solver based on regularized Green's function solutions to obtain exact free-space boundary conditions while using fast Fourier transforms for computational efficiency. Multiresolution is a achieved through local refinement patches and regulari......We present a novel high order multiresolution Poisson solver based on regularized Green's function solutions to obtain exact free-space boundary conditions while using fast Fourier transforms for computational efficiency. Multiresolution is a achieved through local refinement patches...... and regularized Green's functions corresponding to the difference in the spatial resolution between the patches. The full solution is obtained utilizing the linearity of the Poisson equation enabling super-position of solutions. We show that the multiresolution Poisson solver produces convergence rates...... that correspond to the regularization order of the derived Green's functions....
Could Regular Pot Smoking Harm Vision?
... fullstory_162441.html Could Regular Pot Smoking Harm Vision? Study suggests that it might slow signaling among ... may be linked to a limited degree of vision impairment, a new French study suggests. The finding ...
Regular-fat dairy and human health
Astrup, Arne; Bradley, Beth H Rice; Brenna, J Thomas
2016-01-01
In recent history, some dietary recommendations have treated dairy fat as an unnecessary source of calories and saturated fat in the human diet. These assumptions, however, have recently been brought into question by current research on regular fat dairy products and human health. In an effort...... dairy foods have on human health. The emerging scientific evidence indicates that the consumption of regular fat dairy foods is not associated with an increased risk of cardiovascular disease and inversely associated with weight gain and the risk of obesity. Dairy foods, including regular-fat milk...... to disseminate, explore and discuss the state of the science on the relationship between regular fat dairy products and health, symposia were programmed by dairy industry organizations in Europe and North America at The Eurofed Lipids Congress (2014) in France, The Dairy Nutrition Annual Symposium (2014...
The regularization of Old English weak verbs
Marta Tío Sáenz
2015-07-01
Full Text Available This article deals with the regularization of non-standard spellings of the verbal forms extracted from a corpus. It addresses the question of what the limits of regularization are when lemmatizing Old English weak verbs. The purpose of such regularization, also known as normalization, is to carry out lexicological analysis or lexicographical work. The analysis concentrates on weak verbs from the second class and draws on the lexical database of Old English Nerthus, which has incorporated the texts of the Dictionary of Old English Corpus. As regards the question of the limits of normalization, the solution adopted are, in the first place, that when it is necessary to regularize, normalization is restricted to correspondences based on dialectal and diachronic variation and, secondly, that normalization has to be unidirectional.
On π-regularity of General Rings
CHEN WEI-XING; CUI SHU-YING
2010-01-01
A general ring means an associative ring with or without identity. An idempotent e in a general ring I is called left (right) semicentral if for every x∈ I,xe = exe (ex = exe). And I is called semiabelian ff every idempotent in I is left or right semicentral. It is proved that a semiabelian general ring I is π-regular if and only ff the set N(I) of nilpotent elements in I is an ideal of I and I/N(I) is regular. It follows that if I is a semiabelian general ring and K is an ideal of I,then I is π-regular if and only if both K and I/K are r-regular. Based on this we prove that every semiabelian GVNL-ring is an SGVNL-ring. These generalize several known results on the relevant subject. Furthermore we give a characterization of a semiabelian GVNL-ring.
A Biordered Set Representation of Regular Semigroups
Bing Jun YU; Mang XU
2005-01-01
In this paper, for an arbitrary regular biordered set E, by using biorder-isomorphisms between the ω-ideals of E, we construct a fundamental regular semigroup WE called NH-semigroup of E, whose idempotent biordered set is isomorphic to E. We prove further that WE can be used to give a new representation of general regular semigroups in the sense that, for any regular semigroup S with the idempotent biordered set isomorphic to E, there exists a homomorphism from S to WE whose kernel is the greatest idempotent-separating congruence on S and the image is a full symmetric subsemigroup of WE. Moreover, when E is a biordered set of a semilattice E0, WE is isomorphic to the Munn-semigroup TE0; and when E is the biordered set of a band B, WE is isomorphic to the Hall-semigroup WB.
Regularities and Radicals in Near-rings
N.J. Groenewald
2002-01-01
Let F be a regularity for near-rings and F(R) the largest FR-regular ideal in R. In the first part of this paper, we introduce the concepts of maximal Fmodular ideals and F-primitive near-rings to characterize F(R) for any near-ring regularity F. Under certain conditions, F(R) is equal to the intersection of all the maximal F-modular ideals of R. As examples, we apply this to the different analogs of the Brown-McCoy radicals and also the Behrens radicals. In the last part of this paper, we show that for certain regularities, the class of F-primitive near-rings forms a special class.
Spectral partitioning of random regular blockmodels
Barucca, Paolo
2016-01-01
Graph partitioning problems emerge in a wide variety of complex systems, ranging from biology to finance, but can be rigorously analyzed and solved only for a few graph ensembles. Here, an ensemble of random graphs with regular block structure is introduced, for which analytical results can be obtained. In particular, the spectral density of such random regular blockmodels is computed exactly for a modular, bipartite and core-periphery structure. McKay's law for random regular graphs is found analytically to apply also for regular modular and bipartite structures when blocks are homogeneous. In core-periphery structures, where blocks are intrinsically heterogeneous, a new law is found to apply for the spectral density. Exact solution to the inference problem is provided for the models discussed. All analytical results show perfect agreement with numerical experiments. Final discussion summarizes results and outlines the relevance of the results for the solution of graph partitioning problems in other graph en...
Comparability for ideals of regular rings
CHEN Huanyin
2005-01-01
In this paper we investigate necessary and sufficient conditions under which the ideals possess comparability structure. For regular rings, we prove that every square matrix over ideals satisfying general comparability admits a diagonal reduction by quasi invertible matrices.
Regularity of optimal transport maps and applications
Philippis, Guido
2013-01-01
In this thesis, we study the regularity of optimal transport maps and its applications to the semi-geostrophic system. The first two chapters survey the known theory, in particular there is a self-contained proof of Brenier’ theorem on existence of optimal transport maps and of Caffarelli’s Theorem on Holder continuity of optimal maps. In the third and fourth chapter we start investigating Sobolev regularity of optimal transport maps, while in Chapter 5 we show how the above mentioned results allows to prove the existence of Eulerian solution to the semi-geostrophic equation. In Chapter 6 we prove partial regularity of optimal maps with respect to a generic cost functions (it is well known that in this case global regularity can not be expected). More precisely we show that if the target and source measure have smooth densities the optimal map is always smooth outside a closed set of measure zero.
On Comparison of Adaptive Regularization Methods
Sigurdsson, Sigurdur; Larsen, Jan; Hansen, Lars Kai
2000-01-01
, a very flexible regularization may substitute the need for selection procedures. This paper investigates recently suggested adaptive regularization schemes. Some methods focus directly on minimizing an estimate of the generalization error (either algebraic or empirical), whereas others start from...... different criteria, e.g., the Bayesian evidence. The evidence expresses basically the probability of the model, which is conceptually different from generalization error; however, asymptotically for large training data sets they will converge. First the basic model definition, training and generalization...
Non-autonomous maximal regularity for forms given by elliptic operators of bounded variation
Fackler, Stephan
2017-09-01
We show maximal Lp-regularity for non-autonomous Cauchy problems provided the trace spaces are stable in some parameterized sense and the time dependence is of bounded variation. In particular on L2 (Ω), for Lipschitz domains Ω and under mixed boundary conditions, we obtain maximal Lp-regularity for all p ∈ (1 , 2 ] for elliptic operators with coefficients aij : Ω → C satisfying aij (ṡ , x) ∈ BV uniformly in x ∈ Ω.
A Certain Regular Property of the Method I Construction and Packing Measure
Sheng You WEN
2007-01-01
Let τ be a premeasure on a complete separable metric space and let τ* be the Method I measure constructed from τ . We give conditions on τ such that τ* has a regularity as follows: Every τ* -measurable set has measure equivalent to the supremum of premeasures of its compact subsets. Then we prove that the packing measure has this regularity if and only if the corresponding packing premeasure is locally finite.
On the low regularity of the Benney-Lin equation
Chen, Wengu; Li, Junfeng
2008-03-01
We consider the low regularity of the Benney-Lin equation ut+uux+uxxx+[beta](uxx+uxxxx)+[eta]uxxxxx=0. We established the global well posedness for the initial value problem of Benney-Lin equation in the Sobolev spaces for 0[greater-or-equal, slanted]s>-2, improving the well-posedness result of Biagioni and Linares [H.A. Biaginoi, F. Linares, On the Benney-Lin and Kawahara equation, J. Math. Anal. Appl. 211 (1997) 131-152]. For s<-2 we also prove some ill-posedness issues.
On Regularity of Incompressible Fluid with Shear Dependent Viscosity
Hongjun YUAN; Qiu MENG
2012-01-01
The authors consider a non-Newtonian fluid governed by equations with p-structure in a cubic domain.A fluid is said to be shear thinning (or pseudo-plastic) if 1 ＜p ＜ 2,and shear thickening (or dilatant) if p ＞ 2.The case p ＞ 2 is considered in this paper.To improve the regularity results obtained by Crispo,it is shown that the second-order derivatives of the velocity and the first-order derivative of the pressure belong to suitable spaces,by appealing to anisotropic Sobolev embeddings.
*-Regular Leavitt Path Algebras of Arbitrary Graphs
Gonzalo ARANDA PINO; Kulumani RANGASWAMY; Lia VA(S)
2012-01-01
If K is a field with involution and E an arbitrary graph,the involution from K naturally induces an involution of the Leavitt path algebra LK(E).We show that the involution on LK(E) is proper if the involution on K is positive-definite,even in the case when the graph E is not necessarily finite or row-finite.It has been shown that the Leavitt path algebra LK(E) is regular if and only if E is acyclic.We give necessary and sufficient conditions for LK(E) to be *-regular (i.e.,regular with proper involution).This characterization of *-regularity of a Leavitt path algebra is given in terms of an algebraic property of K,not just a graph-theoretic property of E.This differs from the.known characterizations of various other algebraic properties of a Leavitt path algebra in terms of graphtheoretic properties of E alone.As a corollary,we show that Handelman's conjecture (stating that every *-regular ring is unit-regular) holds for Leavitt path algebras.Moreover,its generalized version for rings with local units also continues to hold for Leavitt path algebras over arbitrary graphs.
Improved Approximate String Matching and Regular Expression Matching on Ziv-Lempel Compressed Texts
Bille, Philip; Fagerberg, Rolf; Gørtz, Inge Li
2007-01-01
We study the approximate string matching and regular expression matching problem for the case when the text to be searched is compressed with the Ziv-Lempel adaptive dictionary compression schemes. We present a time-space trade-off that leads to algorithms improving the previously known...... complexities for both problems. In particular, we significantly improve the space bounds. In practical applications the space is likely to be a bottleneck and therefore this is of crucial importance....
2012-01-01
We introduce and investigate the class of skeletally Dugundji spaces as a skeletal analogue of Dugundji space. The main result states that the following conditions are equivalent for a given space $X$: (i) $X$ is skeletally Dugundji; (ii) Every compactification of $X$ is co-absolute to a Dugundji space; (iii) Every $C^*$-embedding of the absolute $p(X)$ in another space is strongly $\\pi$-regular; (iv) $X$ has a multiplicative lattice in the sense of Shchepin \\cite{s76} consisting of skeletal ...
Guzzo, Massimiliano; Bernardi, Olga; Cardin, Franco
2007-09-01
We provide a new method for the localization of Aubry-Mather sets in quasi-integrable two-dimensional twist maps. Inspired by viscosity theories, we introduce regularization techniques based on the new concept of "relative viscosity and friction," which allows one to obtain regularized parametrizations of invariant sets with irrational rotation number. Such regularized parametrizations allow one to compute a curve in the phase-space that passes near the Aubry-Mather set, and an invariant measure whose density allows one to locate the gaps on the curve. We show applications to the "golden" cantorus of the standard map as well as to a more general case.
Graph Laplacian Regularization for Image Denoising: Analysis in the Continuous Domain.
Pang, Jiahao; Cheung, Gene
2017-04-01
Inverse imaging problems are inherently underdetermined, and hence, it is important to employ appropriate image priors for regularization. One recent popular prior-the graph Laplacian regularizer-assumes that the target pixel patch is smooth with respect to an appropriately chosen graph. However, the mechanisms and implications of imposing the graph Laplacian regularizer on the original inverse problem are not well understood. To address this problem, in this paper, we interpret neighborhood graphs of pixel patches as discrete counterparts of Riemannian manifolds and perform analysis in the continuous domain, providing insights into several fundamental aspects of graph Laplacian regularization for image denoising. Specifically, we first show the convergence of the graph Laplacian regularizer to a continuous-domain functional, integrating a norm measured in a locally adaptive metric space. Focusing on image denoising, we derive an optimal metric space assuming non-local self-similarity of pixel patches, leading to an optimal graph Laplacian regularizer for denoising in the discrete domain. We then interpret graph Laplacian regularization as an anisotropic diffusion scheme to explain its behavior during iterations, e.g., its tendency to promote piecewise smooth signals under certain settings. To verify our analysis, an iterative image denoising algorithm is developed. Experimental results show that our algorithm performs competitively with state-of-the-art denoising methods, such as BM3D for natural images, and outperforms them significantly for piecewise smooth images.
On topological spaces possessing uniformly distributed sequences
Bogachev, V I
2007-01-01
Two classes of topological spaces are introduced on which every probability Radon measure possesses a uniformly distributed sequence or a uniformly tight uniformly distributed sequence. It is shown that these classes are stable under multiplication by completely regular Souslin spaces
Semi-regular biorthogonal pairs and generalized Riesz bases
Inoue, H.
2016-11-01
In this paper we introduce general theories of semi-regular biorthogonal pairs, generalized Riesz bases and its physical applications. Here we deal with biorthogonal sequences {ϕn} and {ψn} in a Hilbert space H , with domains D ( ϕ ) = { x ∈ H ; ∑ k = 0 ∞ |" separators=" ( x | ϕ k ) | 2 |" separators=" ( x | ψ k ) | 2 paper [H. Inoue, J. Math. Phys. 57, 083511 (2016)], we have shown that if ({ϕn}, {ψn}) is a regular biorthogonal pair then both {ϕn} and {ψn} are generalized Riesz bases defined in the work of Inoue and Takakura [J. Math. Phys. 57, 083505 (2016)]. Here we shall show that the same result holds true if the pair is only semi-regular by using operators Tϕ,e, Te,ϕ, Tψ,e, and Te,ψ defined by an orthonormal basis e in H and a biorthogonal pair ({ϕn}, {ψn}). Furthermore, we shall apply this result to pseudo-bosons in the sense of the papers of Bagarello [J. Math. Phys. 51, 023531 (2010); J. Phys. A 44, 015205 (2011); Phys. Rev. A 88, 032120 (2013); and J. Math. Phys. 54, 063512 (2013)].
Enhanced manifold regularization for semi-supervised classification.
Gan, Haitao; Luo, Zhizeng; Fan, Yingle; Sang, Nong
2016-06-01
Manifold regularization (MR) has become one of the most widely used approaches in the semi-supervised learning field. It has shown superiority by exploiting the local manifold structure of both labeled and unlabeled data. The manifold structure is modeled by constructing a Laplacian graph and then incorporated in learning through a smoothness regularization term. Hence the labels of labeled and unlabeled data vary smoothly along the geodesics on the manifold. However, MR has ignored the discriminative ability of the labeled and unlabeled data. To address the problem, we propose an enhanced MR framework for semi-supervised classification in which the local discriminative information of the labeled and unlabeled data is explicitly exploited. To make full use of labeled data, we firstly employ a semi-supervised clustering method to discover the underlying data space structure of the whole dataset. Then we construct a local discrimination graph to model the discriminative information of labeled and unlabeled data according to the discovered intrinsic structure. Therefore, the data points that may be from different clusters, though similar on the manifold, are enforced far away from each other. Finally, the discrimination graph is incorporated into the MR framework. In particular, we utilize semi-supervised fuzzy c-means and Laplacian regularized Kernel minimum squared error for semi-supervised clustering and classification, respectively. Experimental results on several benchmark datasets and face recognition demonstrate the effectiveness of our proposed method.
Channeling power across ecological systems: social regularities in community organizing.
Christens, Brian D; Inzeo, Paula Tran; Faust, Victoria
2014-06-01
Relational and social network perspectives provide opportunities for more holistic conceptualizations of phenomena of interest in community psychology, including power and empowerment. In this article, we apply these tools to build on multilevel frameworks of empowerment by proposing that networks of relationships between individuals constitute the connective spaces between ecological systems. Drawing on an example of a model for grassroots community organizing practiced by WISDOM—a statewide federation supporting local community organizing initiatives in Wisconsin—we identify social regularities (i.e., relational and temporal patterns) that promote empowerment and the development and exercise of social power through building and altering relational ties. Through an emphasis on listening-focused one-to-one meetings, reflection, and social analysis, WISDOM organizing initiatives construct and reinforce social regularities that develop social power in the organizing initiatives and advance psychological empowerment among participant leaders in organizing. These patterns are established by organizationally driven brokerage and mobilization of interpersonal ties, some of which span ecological systems.Hence, elements of these power-focused social regularities can be conceptualized as cross-system channels through which micro-level empowerment processes feed into macro-level exercise of social power, and vice versa. We describe examples of these channels in action, and offer recommendations for theory and design of future action research [corrected] .
Pauli-Villars regularization and Born-Infeld kinematics
Schuller, Frederic P [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Wohlfarth, Mattias N R [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom); Grimm, Thomas W [II. Institut fuer Theoretische Physik, Universitaet Hamburg, 22761 Hamburg (Germany)
2003-10-07
Dynamical symmetries of Born-Infeld theory can be absorbed into the spacetime geometry, giving rise to relativistic kinematics with an additional invariant acceleration scale. The standard Poincare group P is thereby enhanced to its pseudo-complexified version, which is isomorphic to P x P. We construct the irreducible representations of this group, which yields the particle spectrum of a relativistic quantum theory that respects a maximal acceleration. It is found that each standard relativistic particle is associated with a 'pseudo'-partner of equal spin but generically different mass. These pseudo-partners act as Pauli-Villars regulators for the other member of the doublet, as is found from the explicit construction of quantum field theory on pseudo-complex spacetime. Conversely, a Pauli-Villars regularized quantum field theory on real spacetime possesses a field phase space with integrable pseudo-complex structure, which gives rise to a quantum field theory on pseudo-complex spacetime. This equivalence between maximal acceleration kinematics, pseudo-complex quantum field theory and Pauli-Villars regularization rigorously establishes a conjecture on the regularizing property of the maximal acceleration principle in quantum field theory, by Nesterenko, Feoli, Lambiase and Scarpetta.
Alves, Claudianor O.; Miyagaki, Olímpio H.
2017-08-01
In this paper, we establish some results concerning the existence, regularity, and concentration phenomenon of nontrivial solitary waves for a class of generalized variable coefficient Kadomtsev-Petviashvili equation. Variational methods are used to get an existence result, as well as, to study the concentration phenomenon, while the regularity is more delicate because we are leading with functions in an anisotropic Sobolev space.
The Least Regular Order with Respect to a Regular Congruence on Ordered Γ-Semigroups
Manoj SIRIPITUKDET; Aiyared IAMPAN
2012-01-01
The motivation mainly comes from the conditions of congruences to be regular that are of importance and interest in ordered semigroups.In 1981,Sen has introduced the concept of the Γ-semigroups.We can see that any semigroup can be considered as a Γ-semigroup.In this paper,we introduce and characterize the concept of the regular congruences on ordered Γ-semigroups and prove the following statements on an ordered Γ-semigroup M:(1) Every ordered semilattice congruences is a regular congruence.(2) There exists the least regular order on the T-semigroup M/p with respect to a regular congruence p on M.(3) The regular congruences are not ordered semilattice congruences in general.
Tilley, Dana M; Vallejo, Ricardo; Kelley, Courtney A; Benyamin, Ramsin; Cedeño, David L
2015-04-01
Models that simulate clinical conditions are needed to gain an understanding of the mechanism involved during spinal cord stimulation (SCS) treatment of chronic neuropathic pain. An animal model has been developed for continuous SCS in which animals that have been injured to develop neuropathic pain behavior were allowed to carry on with regular daily activities while being stimulated for 72 hours. Sprague-Dawley rats were randomized into each of six different groups (N = 10-13). Three groups included animals in which the spared nerve injury (SNI) was induced. Animals in two of these groups were implanted with a four-contact electrode in the epidural space. Animals in one of these groups received stimulation for 72 hours continuously. Three corresponding sham groups (no SNI) were included. Mechanical and cold-thermal allodynia were evaluated using von Frey filaments and acetone drops, respectively. Mean withdrawal thresholds were compared. Statistical significance was established using one-way ANOVAs followed by Holm-Sidak post hoc analysis. Continuous SCS attenuates mechanical allodynia in animals with neuropathic pain behavior. Mechanical withdrawal threshold increases significantly in SNI animals after 24 and 72 hours stimulation vs. SNI no stimulation (p = 0.007 and p stimulation (p = 0.001 and p Stimulation did not provide recovery to baseline values. SCS did not seem to attenuate cold-thermal allodynia. A continuous SCS model has been developed. Animals with neuropathic pain behavior that were continuously stimulated showed significant increase in withdrawal thresholds proportional to stimulation time. © 2015 International Neuromodulation Society.
A Construction for P-Regular Semigroups
无
2000-01-01
@@A regular semigroup S with a special involution *, i.e., a unaryoperation on S satisfying (x*)*=x, xx*x=x, (xy)*=y*x* x, y S, is called a regular *-semigroup［1］. It has been shown by Yamada［2］ that a regular semigroup S is a regular *-semigroup if and only if ithas a P-system, that is to say, there is a subset P ofE(S) such that (c.1) (1) ( p, q P) pq E(S), pqp P; (2) ( a S) ( | a+ V(a)) aP1a+, a+P1a P.As a generalization of regular *-semigroup and orthodox semigroup,Yamada［3］ defined P-regular semigroup. Let S be a regularsemigroup. A subset P of E(S) is called a C-set in S if (c.2) (1) ( p, q P) pq E(S), pqp P; (2) ( a S) ( a+ V(a)) aP1a+, a+P1a P. In this case, (S,P) forms a P-regular semigroup, innotation S(P). The element a+ in(c.2) (2) is called a P-inverse of a. The set of all P-inverses of a is denoted by VP(a). S(P) is said to bestrongly, meanwhile P is called a strong C-set in S, ifVP(p) P for all p P. A partial groupoid E as well as its partial subgroupoid Pforms a P-regular partial band and is denoted by E(P) if itis exactly the subalgebra of the idempotents in some P-regularsemigroup S(P). In this case, S(P) is called an adjacentsemigroup E(P). All P-regular partial bands are obtained inZhang and He［4］.
Counting colorings of a regular graph
Galvin, David
2012-01-01
At most how many (proper) q-colorings does a regular graph admit? Galvin and Tetali conjectured that among all n-vertex, d-regular graphs with 2d|n, none admits more q-colorings than the disjoint union of n/2d copies of the complete bipartite graph K_{d,d}. In this note we give asymptotic evidence for this conjecture, giving an upper bound on the number of proper q-colorings admitted by an n-vertex, d-regular graph of the form a^n b^{n(1+o(1))/d} (where a and b depend on q and where o(1) goes to 0 as d goes to infinity) that agrees up to the o(1) term with the count of q-colorings of n/2d copies of K_{d,d}. An auxiliary result is an upper bound on the number of colorings of a regular graph in terms of its independence number. For example, we show that for all even q and fixed \\epsilon > 0 there is \\delta=\\delta(\\epsilon,q) such that the number of proper q-colorings admitted by an n-vertex, d-regular graph with no independent set of size n(1-\\epsilon)/2 is at most (a-\\delta)^n.
Modified sparse regularization for electrical impedance tomography.
Fan, Wenru; Wang, Huaxiang; Xue, Qian; Cui, Ziqiang; Sun, Benyuan; Wang, Qi
2016-03-01
Electrical impedance tomography (EIT) aims to estimate the electrical properties at the interior of an object from current-voltage measurements on its boundary. It has been widely investigated due to its advantages of low cost, non-radiation, non-invasiveness, and high speed. Image reconstruction of EIT is a nonlinear and ill-posed inverse problem. Therefore, regularization techniques like Tikhonov regularization are used to solve the inverse problem. A sparse regularization based on L1 norm exhibits superiority in preserving boundary information at sharp changes or discontinuous areas in the image. However, the limitation of sparse regularization lies in the time consumption for solving the problem. In order to further improve the calculation speed of sparse regularization, a modified method based on separable approximation algorithm is proposed by using adaptive step-size and preconditioning technique. Both simulation and experimental results show the effectiveness of the proposed method in improving the image quality and real-time performance in the presence of different noise intensities and conductivity contrasts.
Regular Expression Matching and Operational Semantics
Asiri Rathnayake
2011-08-01
Full Text Available Many programming languages and tools, ranging from grep to the Java String library, contain regular expression matchers. Rather than first translating a regular expression into a deterministic finite automaton, such implementations typically match the regular expression on the fly. Thus they can be seen as virtual machines interpreting the regular expression much as if it were a program with some non-deterministic constructs such as the Kleene star. We formalize this implementation technique for regular expression matching using operational semantics. Specifically, we derive a series of abstract machines, moving from the abstract definition of matching to increasingly realistic machines. First a continuation is added to the operational semantics to describe what remains to be matched after the current expression. Next, we represent the expression as a data structure using pointers, which enables redundant searches to be eliminated via testing for pointer equality. From there, we arrive both at Thompson's lockstep construction and a machine that performs some operations in parallel, suitable for implementation on a large number of cores, such as a GPU. We formalize the parallel machine using process algebra and report some preliminary experiments with an implementation on a graphics processor using CUDA.
Regularities, Natural Patterns and Laws of Nature
Stathis Psillos
2014-02-01
Full Text Available The goal of this paper is to sketch an empiricist metaphysics of laws of nature. The key idea is that there are regularities without regularity-enforcers. Differently put, there are natural laws without law-makers of a distinct metaphysical kind. This sketch will rely on the concept of a natural pattern and more significantly on the existence of a network of natural patterns in nature. The relation between a regularity and a pattern will be analysed in terms of mereology. Here is the road map. In section 2, I will briefly discuss the relation between empiricism and metaphysics, aiming to show that an empiricist metaphysics is possible. In section 3, I will offer arguments against stronger metaphysical views of laws. Then, in section 4 I will motivate nomic objectivism. In section 5, I will address the question ‘what is a regularity?’ and will develop a novel answer to it, based on the notion of a natural pattern. In section 6, I will raise the question: ‘what is a law of nature?’, the answer to which will be: a law of nature is a regularity that is characterised by the unity of a natural pattern.
On a correspondence between regular and non-regular operator monotone functions
Gibilisco, P.; Hansen, Frank; Isola, T.
2009-01-01
We prove the existence of a bijection between the regular and the non-regular operator monotone functions satisfying a certain functional equation. As an application we give a new proof of the operator monotonicity of certain functions related to the Wigner-Yanase-Dyson skew information.......We prove the existence of a bijection between the regular and the non-regular operator monotone functions satisfying a certain functional equation. As an application we give a new proof of the operator monotonicity of certain functions related to the Wigner-Yanase-Dyson skew information....
Shadow of rotating regular black holes
Abdujabbarov, Ahmadjon; Ahmedov, Bobomurat; Ghosh, Sushant G
2016-01-01
We study the shadows cast by the different types of rotating regular black holes viz. Ay\\'on-Beato-Garc\\'ia {(ABG)}, Hayward, and Bardeen. These black holes have in addition to the total mass ($M$) and rotation parameter ($a$), different parameters as electric charge ($Q$), deviation parameter ($g$), and magnetic charge ($g_{*}$), respectively. Interestingly, the size of the shadow is affected by these parameters in addition to the rotation parameter. We found that the radius of the shadow in each case decreases monotonically and the distortion parameter increases when the value of these parameters increase. A comparison with the standard Kerr case is also investigated. We have also studied the influence of the plasma environment around regular black holes to discuss its shadow. The presence of the plasma affects the apparent size of the regular black hole's shadow to be increased due to two effects (i) gravitational redshift of the photons and (ii) radial dependence of plasma density.
Fractional Regularization Term for Variational Image Registration
Rafael Verdú-Monedero
2009-01-01
Full Text Available Image registration is a widely used task of image analysis with applications in many fields. Its classical formulation and current improvements are given in the spatial domain. In this paper a regularization term based on fractional order derivatives is formulated. This term is defined and implemented in the frequency domain by translating the energy functional into the frequency domain and obtaining the Euler-Lagrange equations which minimize it. The new regularization term leads to a simple formulation and design, being applicable to higher dimensions by using the corresponding multidimensional Fourier transform. The proposed regularization term allows for a real gradual transition from a diffusion registration to a curvature registration which is best suited to some applications and it is not possible in the spatial domain. Results with 3D actual images show the validity of this approach.
Landweber iterative regularization for nearfield acoustic holography
BI Chuanxing; CHEN Xinzhao; ZHOU Rong; CHEN Jian
2006-01-01
On the basis of the distributed source boundary point method (DSBPM)-based nearfield acoustic holography (NAH), Landweber iterative regularization method is proposed to stabilize the NAH reconstruction process, control the influence of measurement errors on the reconstructed results and ensure the validity of the reconstructed results. And a new method, the auxiliary surface method, is proposed to determine the optimal iterative number for optimizing the regularization effect. Here, the optimal number is determined by minimizing the relative error between the calculated pressure on the auxiliary surface corresponding to each iterative number and the measured pressure. An experiment on a speaker is investigated to demonstrate the high sensitivity of the reconstructed results to measurement errors and to validate the chosen method of the optimal iterative number and the Landweber iterative regularization method for controlling the influence of measurement errors on the reconstructed results.
Robust super-resolution without regularization
Pham, T Q [Canon Information Systems Research Australia, 1 Thomas Holt drive, North Ryde, NSW 2113 (Australia); Vliet, L J v [Quantitative Imaging Group, Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft (Netherlands); Schutte, K [Electro-Optics Group, TNO Defence, Security and Safety, PO Box 96864, 2509 JG The Hague (Netherlands)
2008-07-15
Super-resolution restoration is the problem of restoring a high-resolution scene from multiple degraded low-resolution images under motion. Due to imaging blur and noise, this problem is ill-posed. Additional constraints such as smoothness of the solution (i.e. regularization) is often required to obtain a stable solution. While regularizing the cost function is a standard practice in image restoration, we propose a restoration algorithm that does not require this extra regularization term. The robustness of the algorithm is achieved by a robust error norm that does not response to intensity outliers. With the outliers suppressed, our solution behaves similarly to a maximum-likelihood solution under the presence of Gaussian noise. The effectiveness of our algorithm is demonstrated with super-resolution restoration of real infrared image sequences under severe aliasing and intensity outliers.
Implementing regularization implicitly via approximate eigenvector computation
Mahoney, Michael W
2010-01-01
Regularization is a powerful technique for extracting useful information from noisy data. Typically, it is implemented by adding some sort of norm constraint to an objective function and then exactly optimizing the modified objective function. This procedure typically leads to optimization problems that are computationally more expensive than the original problem, a fact that is clearly problematic if one is interested in large-scale applications. On the other hand, a large body of empirical work has demonstrated that heuristics, and in some cases approximation algorithms, developed to speed up computations sometimes have the side-effect of performing regularization implicitly. Thus, we consider the question: What is the regularized optimization objective that an approximation algorithm is exactly optimizing? We address this question in the context of computing approximations to the smallest nontrivial eigenvector of a graph Laplacian; and we consider three random-walk-based procedures: one based on the heat ...
Nonlinear electrodynamics and regular black holes
Sajadi, S. N.; Riazi, N.
2017-03-01
In this work, an exact regular black hole solution in General Relativity is presented. The source is a nonlinear electromagnetic field with the algebraic structure T00=T11 for the energy-momentum tensor, partially satisfying the weak energy condition but not the strong energy condition. In the weak field limit, the EM field behaves like the Maxwell field. The solution corresponds to a charged black hole with q≤0.77 m. The metric, the curvature invariants, and the electric field are regular everywhere. The BH is stable against small perturbations of spacetime and using the Weinhold metric, geometrothermodynamical stability has been investigated. Finally we investigate the idea that the observable universe lives inside a regular black hole. We argue that this picture might provide a viable description of universe.
Regularization and Migration Policy in Europe
Philippe de Bruycker
2001-05-01
Full Text Available The following pages present, in a general way, the contents of Regularization of illegal immigrants in the European Union, which includes a comparative synthesis and statistical information for each of the eight countries involved; a description of actions since the beginning of the year 2000; and a systematic analysis of the different categories of foreigners, the types of regularization carried out, and the rules that have governed these actions.In relation to regularization, the author considers the political coherence of the actions taken by the member states as well as how they relate to two ever more crucial aspects of immigration policy –the integration of legal resident immigrants and the fight againstillegal immigration in the context of a control of migratory flows.
Sobolev regularity of the $\\bar{\\partial}$-equation on the Hartogs triangle
Chakrabarti, Debraj
2011-01-01
The regularity of the $\\bar{\\partial}$-problem on the domain $\\{|{z_1}|<|{z_2}|<1\\}$ in $\\mathbb{C}^2$ is studied using $L^2$ methods. Estimates are obtained for the canonical solution in weighted $L^2$-Sobolev spaces with a weight that is singular at the point $(0,0)$. The canonical solution for $\\dbar$ with weights is exact regular in the weighted Sobolev spaces away from the singularity $(0,0)$. In particular, the singularity of the Bergman projection for the Hartogs triangle is contained at the singular point and it does not propagate.
Width Distributions for Convex Regular Polyhedra
Finch, Steven R
2011-01-01
The mean width is a measure on three-dimensional convex bodies that enjoys equal status with volume and surface area [Rota]. As the phrase suggests, it is the mean of a probability density f. We verify formulas for mean widths of the regular tetrahedron and the cube. Higher-order moments of f_tetra and f_cube have not been examined until now. Assume that each polyhedron has edges of unit length. We deduce that the mean square width of the regular tetrahedron is 1/3+(3+sqrt(3))/(3*pi) and the mean square width of the cube is 1+4/pi.
Stability Analysis for Regularized Least Squares Regression
Rudin, Cynthia
2005-01-01
We discuss stability for a class of learning algorithms with respect to noisy labels. The algorithms we consider are for regression, and they involve the minimization of regularized risk functionals, such as L(f) := 1/N sum_i (f(x_i)-y_i)^2+ lambda ||f||_H^2. We shall call the algorithm `stable' if, when y_i is a noisy version of f*(x_i) for some function f* in H, the output of the algorithm converges to f* as the regularization term and noise simultaneously vanish. We consider two flavors of...
Interaction of Regular and Chaotic States
De Pace, A; Weidenmüller, H A
2006-01-01
Modelling the chaotic states in terms of the Gaussian Orthogonal Ensemble of random matrices (GOE), we investigate the interaction of the GOE with regular bound states. The eigenvalues of the latter may or may not be embedded in the GOE spectrum. We derive a generalized form of the Pastur equation for the average Green's function. We use that equation to study the average and the variance of the shift of the regular states, their spreading width, and the deformation of the GOE spectrum non-perturbatively. We compare our results with various perturbative approaches.
Regular transport dynamics produce chaotic travel times.
Villalobos, Jorge; Muñoz, Víctor; Rogan, José; Zarama, Roberto; Johnson, Neil F; Toledo, Benjamín; Valdivia, Juan Alejandro
2014-06-01
In the hope of making passenger travel times shorter and more reliable, many cities are introducing dedicated bus lanes (e.g., Bogota, London, Miami). Here we show that chaotic travel times are actually a natural consequence of individual bus function, and hence of public transport systems more generally, i.e., chaotic dynamics emerge even when the route is empty and straight, stops and lights are equidistant and regular, and loading times are negligible. More generally, our findings provide a novel example of chaotic dynamics emerging from a single object following Newton's laws of motion in a regularized one-dimensional system.
No finite $5$-regular matchstick graph exists
2014-01-01
A graph $G=(V,E)$ is called a unit-distance graph in the plane if there is an injective embedding of $V$ in the plane such that every pair of adjacent vertices are at unit distance apart. If additionally the corresponding edges are non-crossing and all vertices have the same degree $r$ we talk of a regular matchstick graph. Due to Euler's polyhedron formula we have $r\\le 5$. The smallest known $4$-regular matchstick graph is the so called Harborth graph consisting of $52$ vertices. In this ar...
Estrada, Ernesto; de la Pena, Jose A.
2013-01-01
Let G be a graph with set of vertices 1,...,n and adjacency matrix A of size nxn. Let d(i,j)=d, we say that f_d:N->N is a d-function on G if for every pair of vertices i,j and k>=d, we have a_ij^(k)=f_d(k). If this function f_d exists on G we say that G is d-walk regular. We prove that G is d-walk regular if and only if for every pair of vertices i,j at distance
Vagus nerve stimulation Overview By Mayo Clinic Staff Vagus nerve stimulation is a procedure that involves implantation of a device that stimulates the vagus nerve with electrical impulses. There's one vagus nerve on ...
Sumin, M. I.
2015-06-01
A parametric nonlinear programming problem in a metric space with an operator equality constraint in a Hilbert space is studied assuming that its lower semicontinuous value function at a chosen individual parameter value has certain subdifferentiability properties in the sense of nonlinear (nonsmooth) analysis. Such subdifferentiability can be understood as the existence of a proximal subgradient or a Fréchet subdifferential. In other words, an individual problem has a corresponding generalized Kuhn-Tucker vector. Under this assumption, a stable sequential Kuhn-Tucker theorem in nondifferential iterative form is proved and discussed in terms of minimizing sequences on the basis of the dual regularization method. This theorem provides necessary and sufficient conditions for the stable construction of a minimizing approximate solution in the sense of Warga in the considered problem, whose initial data can be approximately specified. A substantial difference of the proved theorem from its classical same-named analogue is that the former takes into account the possible instability of the problem in the case of perturbed initial data and, as a consequence, allows for the inherited instability of classical optimality conditions. This theorem can be treated as a regularized generalization of the classical Uzawa algorithm to nonlinear programming problems. Finally, the theorem is applied to the "simplest" nonlinear optimal control problem, namely, to a time-optimal control problem.
Exploring Regularities for Improving FAÇADE Reconstruction from Point Clouds
Zhou, K.; Gorte, B.; Zlatanova, S.
2016-06-01
(Semi)-automatic facade reconstruction from terrestrial LiDAR point clouds is often affected by both quality of point cloud itself and imperfectness of object recognition algorithms. In this paper, we employ regularities, which exist on façades, to mitigate these problems. For example, doors, windows and balconies often have orthogonal and parallel boundaries. Many windows are constructed with the same shape. They may be arranged at the same lines and distance intervals, so do different windows. By identifying regularities among objects with relatively poor quality, these can be applied to calibrate the objects and improve their quality. The paper focuses on the regularities among the windows, which is the majority of objects on the wall. Regularities are classified into three categories: within an individual window, among similar windows and among different windows. Nine cases are specified as a reference for exploration. A hierarchical clustering method is employed to identify and apply regularities in a feature space, where regularities can be identified from clusters. To find the corresponding features in the nine cases of regularities, two phases are distinguished for similar and different windows. In the first phase, ICP (iterative closest points) is used to identify groups of similar windows. The registered points and a number of transformation matrices are used to identify and apply regularities among similar windows. In the second phase, features are extracted from the boundaries of the different windows. When applying regularities by relocating windows, the connections, called chains, established among the similar windows in the first phase are preserved. To test the performance of the algorithms, two datasets from terrestrial LiDAR point clouds are used. Both show good effects on the reconstructed model, while still matching with original point cloud, preventing over or under-regularization.
Bena, I; Kosower, D A; Roiban, R; Bena, Iosif; Bern, Zvi; Kosower, David A.; Roiban, Radu
2004-01-01
We elucidate the one-loop twistor-space structure corresponding to momentum-space MHV diagrams. We also discuss the infrared divergences, and argue that only a limited set of MHV diagrams contain them. We show how to introduce a twistor-space regulator corresponding to dimensional regularization for the infrared-divergent diagrams. We also evaluate explicitly the `holomorphic anomaly' pointed out by Cachazo, Svrcek, and Witten, and use the result to define modified differential operators which can be used to probe the twistor-space structure of one-loop amplitudes.
Jinping Tang
2017-01-01
Full Text Available Optical tomography is an emerging and important molecular imaging modality. The aim of optical tomography is to reconstruct optical properties of human tissues. In this paper, we focus on reconstructing the absorption coefficient based on the radiative transfer equation (RTE. It is an ill-posed parameter identification problem. Regularization methods have been broadly applied to reconstruct the optical coefficients, such as the total variation (TV regularization and the L1 regularization. In order to better reconstruct the piecewise constant and sparse coefficient distributions, TV and L1 norms are combined as the regularization. The forward problem is discretized with the discontinuous Galerkin method on the spatial space and the finite element method on the angular space. The minimization problem is solved by a Jacobian-based Levenberg-Marquardt type method which is equipped with a split Bregman algorithms for the L1 regularization. We use the adjoint method to compute the Jacobian matrix which dramatically improves the computation efficiency. By comparing with the other imaging reconstruction methods based on TV and L1 regularizations, the simulation results show the validity and efficiency of the proposed method.
On the Rate of Structural Change in Scale Spaces
Gustafsson, David Karl John; Pedersen, Kim Steenstrup; Lauze, Francois Bernard;
2009-01-01
We analyze the rate in which image details are suppressed as a function of the regularization parameter, using first order Tikhonov regularization, Linear Gaussian Scale Space and Total Variation image decomposition. The squared L2-norm of the regularized solution and the residual are studied...... as a function of the regularization parameter. For first order Tikhonov regularization it is shown that the norm of the regularized solution is a convex function, while the norm of the residual is not a concave function. The same result holds for Gaussian Scale Space when the parameter is the variance...
Myeloperoxidase Stimulates Neutrophil Degranulation.
Grigorieva, D V; Gorudko, I V; Sokolov, A V; Kostevich, V A; Vasilyev, V B; Cherenkevich, S N; Panasenko, O M
2016-08-01
Myeloperoxidase, heme enzyme of azurophilic granules in neutrophils, is released into the extracellular space in the inflammation foci. In neutrophils, it stimulates a dose-dependent release of lactoferrin (a protein of specific granules), lysozyme (a protein of specific and azurophilic granules), and elastase (a protein of azurophilic granules). 4-Aminobenzoic acid hydrazide, a potent inhibitor of peroxidase activity of myeloperoxidase, produced no effect on neutrophil degranulation. Using signal transduction inhibitors (genistein, methoxyverapamil, wortmannin, and NiCl2), we demonstrated that myeloperoxidase-induced degranulation of neutrophils resulted from enzyme interaction with the plasma membrane and depends on activation of tyrosine kinases, phosphatidylinositol 3-kinases (PI3K), and calcium signaling. Myeloperoxidase modified by oxidative/halogenation stress (chlorinated and monomeric forms of the enzyme) lost the potency to activate neutrophil degranulation.
Dynamic stabilization of regular linear systems
Weiss, G; Curtain, RF
We consider a general class of infinite-dimensional linear systems, called regular linear systems, for which convenient representations are known to exist both in time and in frequency domain, For this class of systems, we investigate the concepts of stabilizability and detectability, in particular,
Regular and context-free nominal traces
Mezzetti, Gianluca
2016-01-01
Two kinds of automata are presented, for recognising new classes of regular and context-free nominal languages. We compare their expressive power with analogous proposals in the literature, showing that they express novel classes of languages. Although many properties of classical languages hold ...
Neural Classifier Construction using Regularization, Pruning
Hintz-Madsen, Mads; Hansen, Lars Kai; Larsen, Jan;
1998-01-01
In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction...
Deconvolution and Regularization with Toeplitz Matrices
Hansen, Per Christian
2002-01-01
of these discretized deconvolution problems, with emphasis on methods that take the special structure of the matrix into account. Wherever possible, analogies to classical DFT-based deconvolution problems are drawn. Among other things, we present direct methods for regularization with Toeplitz matrices, and we show...
Regular conformal system for Einstein equations
Choquet-Bruhat, Y.; Novello, M.
1987-06-21
We give a system of partial differential equations satisfied by a metric g conformal to an Einstein metric and by the conformal factor ..omega.., regular system in the sense that it does not contain negative powers of ..omega... We use the ideas of Friedrich but we obtain here a hyperbolic system in the sense of Leray, by a different method.
Bayesian regularization of diffusion tensor images
Frandsen, Jesper; Hobolth, Asger; Østergaard, Leif;
2007-01-01
several directions. The measured diffusion coefficients and thereby the diffusion tensors are subject to noise, leading to possibly flawed representations of the three dimensional fibre bundles. In this paper we develop a Bayesian procedure for regularizing the diffusion tensor field, fully utilizing...
Regularity of rotational travelling water waves.
Escher, Joachim
2012-04-13
Several recent results on the regularity of streamlines beneath a rotational travelling wave, along with the wave profile itself, will be discussed. The survey includes the classical water wave problem in both finite and infinite depth, capillary waves and solitary waves as well. A common assumption in all models to be discussed is the absence of stagnation points.
Contour Propagation With Riemannian Elasticity Regularization
Bjerre, Troels; Hansen, Mads Fogtmann; Sapru, W.;
2011-01-01
the planning CT onto the rescans and correcting to reflect actual anatomical changes. For deformable registration, a free-form, multi-level, B-spline deformation model with Riemannian elasticity, penalizing non-rigid local deformations, and volumetric changes, was used. Regularization parameters was defined...
NOTE ON REGULAR D-OPTIMAL MATRICES
李乔良
2003-01-01
Let A be aj ×d (0,1) matrix. It is known that ifj = 2k-1is odd, then det(AAT) ≤(j+1)((j+1)d/4j)j; ifj is even, then det(AAT) ≤ (j+1)((j+2)d/4(j+1))j. A is called a regularD-optimal matrix if it satisfies the equality of the above bounds. In this note, it is proved thatifj = 2k - 1 is odd, then A is a regular D-optimal matrix if and only if A is the adjacent matrixof a (2k - 1, k, (j + 1)d/4j)-BIBD; if j ＝ 2k is even, then A is a regular D-optimal matrix ifand only if A can be obtained from the adjacent matrix B of a (2k + 1, k + 1, (j + 2)d/4(j + 1))-BIBD by deleting any one row from B. Three 21 × 42 regular D-optimal matrices, which wereunknown in [11], are also provided.
A Note on Left Regular Semiring
N. Sulochana
2016-08-01
Full Text Available In this paper we have focused on the additive and multiplicative identity „e‟ and determine the additive and multiplicative semigroups. Here we established that, A semiring S in which (S, + and (S, • are left singular semigroups, then S is a left regular semiring. We have framed an example for this proposition by considering a two element set
Tikhonov Regularization and Total Least Squares
Golub, G. H.; Hansen, Per Christian; O'Leary, D. P.
2000-01-01
formulation involves a least squares problem, can be recast in a total least squares formulation suited for problems in which both the coefficient matrix and the right-hand side are known only approximately. We analyze the regularizing properties of this method and demonstrate by a numerical example that...
Creativity Workshops in the Regular Classroom.
Mildrum, Nancy King
2000-01-01
This article describes implementation of a creativity curriculum, Ten Lessons in Creativity, with gifted and typical students in elementary and middle school settings. It discusses creativity instruction as a bridge between gifted and regular education, ways that creativity workshops affirm the highly creative child, creativity and self-esteem,…
Regularization of turbulence - a comprehensive modeling approach
Geurts, B. J.
2011-12-01
Turbulence readily arises in numerous flows in nature and technology. The large number of degrees of freedom of turbulence poses serious challenges to numerical approaches aimed at simulating and controlling such flows. While the Navier-Stokes equations are commonly accepted to precisely describe fluid turbulence, alternative coarsened descriptions need to be developed to cope with the wide range of length and time scales. These coarsened descriptions are known as large-eddy simulations in which one aims to capture only the primary features of a flow, at considerably reduced computational effort. Such coarsening introduces a closure problem that requires additional phenomenological modeling. A systematic approach to the closure problem, know as regularization modeling, will be reviewed. Its application to multiphase turbulent will be illustrated in which a basic regularization principle is enforced to physically consistently approximate momentum and scalar transport. Examples of Leray and LANS-alpha regularization are discussed in some detail, as are compatible numerical strategies. We illustrate regularization modeling to turbulence under the influence of rotation and buoyancy and investigate the accuracy with which particle-laden flow can be represented. A discussion of the numerical and modeling errors incurred will be given on the basis of homogeneous isotropic turbulence.
Coprime factorization for regular linear systems
Curtain, R; Weiss, G; Weiss, M
1996-01-01
Mild sufficient conditions are given for the existence of a doubly coprime factorization of the transfer function of a regular linear system, as well as formulae for such a factorization. The results are illustrated by two examples of delay systems, one of which has infinitely many unstable poles. C
Dynamic stabilization of regular linear systems
Weiss, G; Curtain, RF
1997-01-01
We consider a general class of infinite-dimensional linear systems, called regular linear systems, for which convenient representations are known to exist both in time and in frequency domain, For this class of systems, we investigate the concepts of stabilizability and detectability, in particular,
Annotation of regular polysemy and underspecification
Martínez Alonso, Héctor; Pedersen, Bolette Sandford; Bel, Núria
2013-01-01
We present the result of an annotation task on regular polysemy for a series of seman- tic classes or dot types in English, Dan- ish and Spanish. This article describes the annotation process, the results in terms of inter-encoder agreement, and the sense distributions obtained with two methods...
Strategies of Teachers in the Regular Classroom
De Leeuw, Renske Ria; De Boer, Anke Aaltje
2016-01-01
It is known that regular schoolteachers have difficulties in educating students with social, emotional and behavioral difficulties (SEBD), mainly because of their disruptive behavior. In order to manage the disruptive behavior of students with SEBD many advices and strategies are provided in educational literature. However, very little is known…
Strategies of teachers in the regular classroom
de Leeuw, Renske Ria; de Boer, Anke Aaltje
2016-01-01
It is known that regular schoolteachers have difficulties in educating students with social, emotional and behavioral difficulties (SEBD), mainly because of their disruptive behavior. In order to manage the disruptive behavior of students with SEBD many advices and strategies are provided in educati
Regular-fat dairy and human health
Astrup, Arne; Bradley, Beth H Rice; Brenna, J Thomas;
2016-01-01
to disseminate, explore and discuss the state of the science on the relationship between regular fat dairy products and health, symposia were programmed by dairy industry organizations in Europe and North America at The Eurofed Lipids Congress (2014) in France, The Dairy Nutrition Annual Symposium (2014...
On the regularization procedure in classical electrodynamics
Yaremko, Yu
2003-01-01
We consider the self-action problem in classical electrodynamics. A strict geometrical sense of commonly used renormalization of mass is made. A regularization procedure is proposed which relies on energy-momentum and angular momentum balance equations. We correct the expression for angular momentum tensor obtained by us in a previous paper (2002 J. Phys. A: Math. Gen. 35 831).
The canonical controller and its regularity
Willems, Jan C.; Belur, Madhu N.; Anak Agung Julius, A.A.J.; Trentelman, Harry L.
2003-01-01
This paper deals with properties of canonical controllers. We first specify the behavior that they implement. It follows that a canonical controller implements the desired controlled behavior if and only if the desired behavior is implementable. We subsequently investigate the regularity of the cont
Stabilization, Pole Placement, and Regular Implementability
Belur, Madhu N.; Trentelman, H.L.
2002-01-01
In this paper, we study control by interconnection of linear differential systems. We give necessary and sufficient conditions for regular implementability of a given linear differential system. We formulate the problems of stabilization and pole placement as problems of finding a suitable, regularl
Generalisation of Regular and Irregular Morphological Patterns.
Prasada, Sandeep; and Pinker, Steven
1993-01-01
When it comes to explaining English verbs' patterns of regular and irregular generalization, single-network theories have difficulty with the former, rule-only theories with the latter process. Linguistic and psycholinguistic evidence, based on observation during experiments and simulations in morphological pattern generation, independently call…
Doeltgen, Sebastian H; McAllister, Suzanne M; Ridding, Michael C
2012-09-01
The objective of this study was to assess whether the simultaneous application of slow-oscillation transcranial direct current stimulation enhances the neuroplastic response to transcranial magnetic theta burst stimulation. Motor evoked potential amplitude was assessed at baseline and at regular intervals up to 60 min following continuous theta burst stimulation, slow-oscillation transcranial direct current stimulation, and the simultaneous application of these paradigms. In addition, the electroencephalographic power spectra of slow and fast delta, and theta frequency bands recorded over the motor cortex were analyzed prior to and up to 5 min following each intervention. There was longer-lasting motor evoked potential suppression following the simultaneous application of continuous theta burst stimulation and slow-oscillation transcranial direct current stimulation compared with when continuous theta burst stimulation was applied alone. Slow-oscillation transcranial direct current stimulation applied alone did not modulate the motor evoked potential amplitude. No significant changes in spectral power were observed following slow-oscillation transcranial direct current stimulation. Simultaneous application of continuous theta burst stimulation and slow-oscillation transcranial direct current stimulation may provide an approach to prolong the induction of neuroplastic changes in motor cortical circuits by repetitive transcranial magnetic brain stimulation.
Asymmetry Factors Shaping Regular and Irregular Bursting Rhythms in Central Pattern Generators
Elices, Irene; Varona, Pablo
2017-01-01
Central Pattern Generator (CPG) circuits are neural networks that generate rhythmic motor patterns. These circuits are typically built of half-center oscillator subcircuits with reciprocally inhibitory connections. Another common property in many CPGs is the remarkable rich spiking-bursting dynamics of their constituent cells, which balance robustness and flexibility to generate their joint coordinated rhythms. In this paper, we use conductance-based models and realistic connection topologies inspired by the crustacean pyloric CPG to address the study of asymmetry factors shaping CPG bursting rhythms. In particular, we assess the role of asymmetric maximal synaptic conductances, time constants and gap-junction connectivity to establish the regularity of half-center oscillator based CPGs. We map and characterize the synaptic parameter space that lead to regular and irregular bursting activity in these networks. The analysis indicates that asymmetric configurations display robust regular rhythms and that large regions of both regular and irregular but coordinated rhythms exist as a function of the asymmetry in the circuit. Our results show that asymmetry both in the maximal conductances and in the temporal dynamics of mutually inhibitory neurons can synergistically contribute to shape wide regimes of regular spiking-bursting activity in CPGs. Finally, we discuss how a closed-loop protocol driven by a regularity goal can be used to find and characterize regular regimes when there is not time to perform an exhaustive search, as in most experimental studies. PMID:28261081
Quasi Regular Polyhedra and Their Duals with Coxeter Symmetries Represented by Quaternions II
Koca, Mehmet; Shidhani, Saleh Al-
2010-01-01
In this paper we construct the quasi regular polyhedra and their duals which are the generalizations of the Archimedean and Catalan solids respectively. This work is an extension of two previous papers of ours which were based on the Archimedean and Catalan solids obtained as the orbits of the Coxeter groups . When these groups act on an arbitrary vector in 3D Euclidean space they generate the orbits corresponding to the quasi regular polyhedra. Special choices of the vectors lead to the platonic and Archimedean solids. In general, the faces of the quasi regular polyhedra consist of the equilateral triangles, squares, regular pentagons as well as rectangles, isogonal hexagons, isogonal octagons, and isogonal decagons depending on the choice of the Coxeter groups of interest. We follow the quaternionic representation of the group elements of the Coxeter groups which necessarily leads to the quaternionic representation of the vertices. We note the fact that the molecule can best be represented by a truncated ic...
Bedoin, Nathalie; Brisseau, Lucie; Molinier, Pauline; Roch, Didier; Tillmann, Barbara
2016-01-01
Children with developmental language disorders have been shown to be also impaired in rhythm and meter perception. Temporal processing and its link to language processing can be understood within the dynamic attending theory. An external stimulus can stimulate internal oscillators, which orient attention over time and drive speech signal segmentation to provide benefits for syntax processing, which is impaired in various patient populations. For children with Specific Language Impairment (SLI) and dyslexia, previous research has shown the influence of an external rhythmic stimulation on subsequent language processing by comparing the influence of a temporally regular musical prime to that of a temporally irregular prime. Here we tested whether the observed rhythmic stimulation effect is indeed due to a benefit provided by the regular musical prime (rather than a cost subsequent to the temporally irregular prime). Sixteen children with SLI and 16 age-matched controls listened to either a regular musical prime sequence or an environmental sound scene (without temporal regularities in event occurrence; i.e., referred to as “baseline condition”) followed by grammatically correct and incorrect sentences. They were required to perform grammaticality judgments for each auditorily presented sentence. Results revealed that performance for the grammaticality judgments was better after the regular prime sequences than after the baseline sequences. Our findings are interpreted in the theoretical framework of the dynamic attending theory (Jones, 1976) and the temporal sampling (oscillatory) framework for developmental language disorders (Goswami, 2011). Furthermore, they encourage the use of rhythmic structures (even in non-verbal materials) to boost linguistic structure processing and outline perspectives for rehabilitation. PMID:27378833
Liu, Jinzhen; Ling, Lin; Li, Gang
2013-07-01
A Tikhonov regularization method in the inverse problem of electrical impedance tomography (EIT) often results in a smooth distribution reconstruction, with which we can barely make a clear separation between the inclusions and background. The recently popular total variation (TV)regularization method including the lagged diffusivity (LD) method can sharpen the edges, and is robust to noise in a small convergence region. Therefore, in this paper, we propose a novel regularization method combining the Tikhonov and LD regularization methods. Firstly, we clarify the implementation details of the Tikhonov, LD and combined methods in two-dimensional open EIT by performing the current injection and voltage measurement on one boundary of the imaging object. Next, we introduce a weighted parameter to the Tikhonov regularization method aiming to explore the effect of the weighted parameter on the resolution and quality of reconstruction images with the inclusion at different depths. Then, we analyze the performance of these algorithms with noisy data. Finally, we evaluate the effect of the current injection pattern on reconstruction quality and propose a modified current injection pattern.The results indicate that the combined regularization algorithm with stable convergence is able to improve the reconstruction quality with sharp contrast and more robust to noise in comparison to the Tikhonov and LD regularization methods solely. In addition, the results show that the current injection pattern with a bigger driver angle leads to a better reconstruction quality.
ZHANG; Xiaoxia; GUO; Maozheng
2005-01-01
In this paper, it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators, where A is a Woronowicz C*-algebra acted upon by a discrete group G. Meanwhile, it is also shown that the regular covariant C*-algebra is the Woronowicz C*-algebra which corresponds to a multiplicative unitary. Finally, an explicit description of the multiplicative unitary operator for C(SUq(2))×α Z is given in terms of those of the Woronowicz C*-algebra C(SUq(2)) and the discrete group G.
Cubic Trigonometric B-spline Galerkin Methods for the Regularized Long Wave Equation
Irk, Dursun; Keskin, Pinar
2016-10-01
A numerical solution of the Regularized Long Wave (RLW) equation is obtained using Galerkin finite element method, based on Crank Nicolson method for the time integration and cubic trigonometric B-spline functions for the space integration. After two different linearization techniques are applied, the proposed algorithms are tested on the problems of propagation of a solitary wave and interaction of two solitary waves.
Regularity criteria for 3D Boussinesq equations with zero thermal diffusion
Zhuan Ye
2015-04-01
Full Text Available In this article, we consider the three-dimensional (3D incompressible Boussinesq equations with zero thermal diffusion. We establish a regularity criterion for the local smooth solution in the framework of Besov spaces in terms of the velocity only.
A Remark on the Regularity Criterion for the 3D Boussinesq Equations Involving the Pressure Gradient
Zujin Zhang
2014-01-01
Full Text Available We consider the three-dimensional Boussinesq equations and obtain a regularity criterion involving the pressure gradient in the Morrey-Companato space Mp,q. This extends and improves the result of Gala (Gala 2013 for the Navier-Stokes equations.
LP-REGULARITY FOR A CLASS OF PSEUDODIFFERENTIAL OPERATORS IN Rn
A Morando
2005-01-01
We study here a class of pseudodifferential operators with weighted symbols of Shubin type. First, we develop the basic elements of the pseudodifferential calculus for these operators, proving in particular a result of LP-boundedness. Then we derive regularity results in the frame of suitably defined functional spaces of Sobolev type.
Zeng Yuesheng
2000-01-01
We prove C1,α almost everywhere regularity for weak solutions in the space W1,k(ΩΩ, RN) of the systems -DαAia(x, u, Du) = Bi(x, u, Du) under the weak / A(x0, u,p + Dφ). Dφdy _＞ λ/(|DФ|2 + |DФ|k)dy.
Improved Approximate String Matching and Regular Expression Matching on Ziv-Lempel Compressed Texts
Bille, Philip; Fagerberg, Rolf; Gørtz, Inge Li
2009-01-01
We study the approximate string matching and regular expression matching problem for the case when the text to be searched is compressed with the Ziv-Lempel adaptive dictionary compression schemes. We present a time-space trade-off that leads to algorithms improving the previously known...
REGULARITY CRITERIA FOR WEAK SOLUTION TO THE 3D MAGNETOHYDRODYNAMIC EQUATIONS
Wang Yuzhu; Wang Shubin; Wang Yinxia
2012-01-01
In this article,regularity criteria for the 3D magnetohydrodynamic equations are investigated.Some sufficient integrability conditions on two components or the gradient of two components of u + B and u - B in Morrey-Campanato spaces are obtained.
Regularization and Iterative Methods for Monotone Variational Inequalities
Xiubin Xu
2010-01-01
Full Text Available We provide a general regularization method for monotone variational inequalities, where the regularizer is a Lipschitz continuous and strongly monotone operator. We also introduce an iterative method as discretization of the regularization method. We prove that both regularization and iterative methods converge in norm.
Power-law regularities in human language
Mehri, Ali; Lashkari, Sahar Mohammadpour
2016-11-01
Complex structure of human language enables us to exchange very complicated information. This communication system obeys some common nonlinear statistical regularities. We investigate four important long-range features of human language. We perform our calculations for adopted works of seven famous litterateurs. Zipf's law and Heaps' law, which imply well-known power-law behaviors, are established in human language, showing a qualitative inverse relation with each other. Furthermore, the informational content associated with the words ordering, is measured by using an entropic metric. We also calculate fractal dimension of words in the text by using box counting method. The fractal dimension of each word, that is a positive value less than or equal to one, exhibits its spatial distribution in the text. Generally, we can claim that the Human language follows the mentioned power-law regularities. Power-law relations imply the existence of long-range correlations between the word types, to convey an especial idea.
Towards lattice-regularized Quantum Gravity
Diakonov, Dmitri
2011-01-01
Using the Cartan formulation of General Relativity, we construct a well defined lattice-regularized theory capable to describe large non-perturbative quantum fluctuations of the frame field (or the metric) and of the spin connection. To that end we need to present the tetrad by a composite field built as a bilinear combination of fermion fields. The theory is explicitly invariant under local Lorentz transformations and, in the continuum limit, under general covariant transformations, or diffeomorphisms. Being well defined for large and fast varying fields at the ultraviolet cutoff, the theory simultaneously has chances of reproducing standard General Relativity in the infrared continuum limit. The present regularization of quantum gravity opens new possibilities of its unification with the Standard Model.
Basic analysis of regularized series and products
Jorgenson, Jay A
1993-01-01
Analytic number theory and part of the spectral theory of operators (differential, pseudo-differential, elliptic, etc.) are being merged under amore general analytic theory of regularized products of certain sequences satisfying a few basic axioms. The most basic examples consist of the sequence of natural numbers, the sequence of zeros with positive imaginary part of the Riemann zeta function, and the sequence of eigenvalues, say of a positive Laplacian on a compact or certain cases of non-compact manifolds. The resulting theory is applicable to ergodic theory and dynamical systems; to the zeta and L-functions of number theory or representation theory and modular forms; to Selberg-like zeta functions; andto the theory of regularized determinants familiar in physics and other parts of mathematics. Aside from presenting a systematic account of widely scattered results, the theory also provides new results. One part of the theory deals with complex analytic properties, and another part deals with Fourier analys...
Tracking magnetogram proper motions by multiscale regularization
Jones, Harrison P.
1995-01-01
Long uninterrupted sequences of solar magnetograms from the global oscillations network group (GONG) network and from the solar and heliospheric observatory (SOHO) satellite will provide the opportunity to study the proper motions of magnetic features. The possible use of multiscale regularization, a scale-recursive estimation technique which begins with a prior model of how state variables and their statistical properties propagate over scale. Short magnetogram sequences are analyzed with the multiscale regularization algorithm as applied to optical flow. This algorithm is found to be efficient, provides results for all the spatial scales spanned by the data and provides error estimates for the solutions. It is found that the algorithm is less sensitive to evolutionary changes than correlation tracking.
Testing the Equivalence of Regular Languages
Marco Almeida
2009-07-01
Full Text Available The minimal deterministic finite automaton is generally used to determine regular languages equality. Antimirov and Mosses proposed a rewrite system for deciding regular expressions equivalence of which Almeida et al. presented an improved variant. Hopcroft and Karp proposed an almost linear algorithm for testing the equivalence of two deterministic finite automata that avoids minimisation. In this paper we improve the best-case running time, present an extension of this algorithm to non-deterministic finite automata, and establish a relationship between this algorithm and the one proposed in Almeida et al. We also present some experimental comparative results. All these algorithms are closely related with the recent coalgebraic approach to automata proposed by Rutten.
Totally Corrective Boosting for Regularized Risk Minimization
Shen, Chunhua; Barnes, Nick
2010-01-01
Consideration of the primal and dual problems together leads to important new insights into the characteristics of boosting algorithms. In this work, we propose a general framework that can be used to design new boosting algorithms. A wide variety of machine learning problems essentially minimize a regularized risk functional. We show that the proposed boosting framework, termed CGBoost, can accommodate various loss functions and different regularizers in a totally-corrective optimization fashion. We show that, by solving the primal rather than the dual, a large body of totally-corrective boosting algorithms can actually be efficiently solved and no sophisticated convex optimization solvers are needed. We also demonstrate that some boosting algorithms like AdaBoost can be interpreted in our framework--even their optimization is not totally corrective. We empirically show that various boosting algorithms based on the proposed framework perform similarly on the UCIrvine machine learning datasets [1] that we hav...
A short proof of increased parabolic regularity
Stephen Pankavich
2015-08-01
Full Text Available We present a short proof of the increased regularity obtained by solutions to uniformly parabolic partial differential equations. Though this setting is fairly introductory, our new method of proof, which uses a priori estimates and an inductive method, can be extended to prove analogous results for problems with time-dependent coefficients, advection-diffusion or reaction diffusion equations, and nonlinear PDEs even when other tools, such as semigroup methods or the use of explicit fundamental solutions, are unavailable.
Regular aspirin use and lung cancer risk
Cummings K
2002-11-01
Full Text Available Abstract Background Although a large number of epidemiological studies have examined the role of aspirin in the chemoprevention of colon cancer and other solid tumors, there is a limited body of research focusing on the association between aspirin and lung cancer risk. Methods We conducted a hospital-based case-control study to evaluate the role of regular aspirin use in lung cancer etiology. Study participants included 868 cases with primary, incident lung cancer and 935 hospital controls with non-neoplastic conditions who completed a comprehensive epidemiological questionnaire. Participants were classified as regular aspirin users if they had taken the drug at least once a week for at least one year. Results Results indicated that lung cancer risk was significantly lower for aspirin users compared to non-users (adjusted OR = 0.57; 95% CI 0.41–0.78. Although there was no clear evidence of a dose-response relationship, we observed risk reductions associated with greater frequency of use. Similarly, prolonged duration of use and increasing tablet years (tablets per day × years of use was associated with reduced lung cancer risk. Risk reductions were observed in both sexes, but significant dose response relationships were only seen among male participants. When the analyses were restricted to former and current smokers, participants with the lowest cigarette exposure tended to benefit most from the potential chemopreventive effect of aspirin. After stratification by histology, regular aspirin use was significantly associated with reduced risk of small cell lung cancer and non-small cell lung cancer. Conclusions Overall, results from this hospital-based case-control study suggest that regular aspirin use may be associated with reduced risk of lung cancer.
Bouncing cosmology inspired by regular black holes
Neves, J. C. S.
2017-09-01
In this article, we present a bouncing cosmology inspired by a family of regular black holes. This scale-dependent cosmology deviates from the cosmological principle by means of a scale factor which depends on the time and the radial coordinate as well. The model is isotropic but not perfectly homogeneous. That is, this cosmology describes a universe almost homogeneous only for large scales, such as our observable universe.
Stream Processing Using Grammars and Regular Expressions
Rasmussen, Ulrik Terp
Kleenex, a language for expressing high-performance streaming string processing programs as regular grammars with embedded semantic actions, and its compilation to streaming string transducers with worst-case linear-time performance. Its underlying theory is based on transducer decomposition into oracle...... is based on a bottom-up tabulation algorithm reformulated using least fixed points and evaluated using an instance of the chaotic iteration scheme by Cousot and Cousot....
Computational Topology for Regular Closed Sets
project, The I-TANGO; :; Peters, T J; Bisceglio, J.; Ferguson, D. R.; Hoffmann, C.M.; Maekawa, T.; Patrikalakis, N.M.; Sakkalis, T.; N F Stewart
2004-01-01
The Boolean algebra of regular closed sets is prominent in topology, particularly as a dual for the Stone-Cech compactification. This algebra is also central for the theory of geometric computation, as a representation for combinatorial operations on geometric sets. However, the issue of computational approximation introduces unresolved subtleties that do not occur within "pure" topology. One major effort towards reconciling this mathematical theory with computational practice is our ongoing ...
Hyperspectral Image Recovery via Hybrid Regularization
Arablouei, Reza; de Hoog, Frank
2016-12-01
Natural images tend to mostly consist of smooth regions with individual pixels having highly correlated spectra. This information can be exploited to recover hyperspectral images of natural scenes from their incomplete and noisy measurements. To perform the recovery while taking full advantage of the prior knowledge, we formulate a composite cost function containing a square-error data-fitting term and two distinct regularization terms pertaining to spatial and spectral domains. The regularization for the spatial domain is the sum of total-variation of the image frames corresponding to all spectral bands. The regularization for the spectral domain is the l1-norm of the coefficient matrix obtained by applying a suitable sparsifying transform to the spectra of the pixels. We use an accelerated proximal-subgradient method to minimize the formulated cost function. We analyze the performance of the proposed algorithm and prove its convergence. Numerical simulations using real hyperspectral images exhibit that the proposed algorithm offers an excellent recovery performance with a number of measurements that is only a small fraction of the hyperspectral image data size. Simulation results also show that the proposed algorithm significantly outperforms an accelerated proximal-gradient algorithm that solves the classical basis-pursuit denoising problem to recover the hyperspectral image.
Charge-regularization effects on polyelectrolytes
Muthukumar, Murugappan
2012-02-01
When electrically charged macromolecules are dispersed in polar solvents, their effective net charge is generally different from their chemical charges, due to competition between counterion adsorption and the translational entropy of dissociated counterions. The effective charge changes significantly as the experimental conditions change such as variations in solvent quality, temperature, and the concentration of added small electrolytes. This charge-regularization effect leads to major difficulties in interpreting experimental data on polyelectrolyte solutions and challenges in understanding the various polyelectrolyte phenomena. Even the most fundamental issue of experimental determination of molar mass of charged macromolecules by light scattering method has been difficult so far due to this feature. We will present a theory of charge-regularization of flexible polyelectrolytes in solutions and discuss the consequences of charge-regularization on (a) experimental determination of molar mass of polyelectrolytes using scattering techniques, (b) coil-globule transition, (c) macrophase separation in polyelectrolyte solutions, (c) phase behavior in coacervate formation, and (d) volume phase transitions in polyelectrolyte gels.
Regularization Parameter Selections via Generalized Information Criterion.
Zhang, Yiyun; Li, Runze; Tsai, Chih-Ling
2010-03-01
We apply the nonconcave penalized likelihood approach to obtain variable selections as well as shrinkage estimators. This approach relies heavily on the choice of regularization parameter, which controls the model complexity. In this paper, we propose employing the generalized information criterion (GIC), encompassing the commonly used Akaike information criterion (AIC) and Bayesian information criterion (BIC), for selecting the regularization parameter. Our proposal makes a connection between the classical variable selection criteria and the regularization parameter selections for the nonconcave penalized likelihood approaches. We show that the BIC-type selector enables identification of the true model consistently, and the resulting estimator possesses the oracle property in the terminology of Fan and Li (2001). In contrast, however, the AIC-type selector tends to overfit with positive probability. We further show that the AIC-type selector is asymptotically loss efficient, while the BIC-type selector is not. Our simulation results confirm these theoretical findings, and an empirical example is presented. Some technical proofs are given in the online supplementary material.
Relational-Regularized Discriminative Sparse Learning for Alzheimer's Disease Diagnosis.
Lei, Baiying; Yang, Peng; Wang, Tianfu; Chen, Siping; Ni, Dong
2017-01-16
Accurate identification and understanding informative feature is important for early Alzheimer's disease (AD) prognosis and diagnosis. In this paper, we propose a novel discriminative sparse learning method with relational regularization to jointly predict the clinical score and classify AD disease stages using multimodal features. Specifically, we apply a discriminative learning technique to expand the class-specific difference and include geometric information for effective feature selection. In addition, two kind of relational information are incorporated to explore the intrinsic relationships among features and training subjects in terms of similarity learning. We map the original feature into the target space to identify the informative and predictive features by sparse learning technique. A unique loss function is designed to include both discriminative learning and relational regularization methods. Experimental results based on a total of 805 subjects [including 226 AD patients, 393 mild cognitive impairment (MCI) subjects, and 186 normal controls (NCs)] from AD neuroimaging initiative database show that the proposed method can obtain a classification accuracy of 94.68% for AD versus NC, 80.32% for MCI versus NC, and 74.58% for progressive MCI versus stable MCI, respectively. In addition, we achieve remarkable performance for the clinical scores prediction and classification label identification, which has efficacy for AD disease diagnosis and prognosis. The algorithm comparison demonstrates the effectiveness of the introduced learning techniques and superiority over the state-of-the-arts methods.
General theory of regular biorthogonal pairs and its physical operators
Inoue, H.
2016-08-01
In this paper, we introduce a general theory of regular biorthogonal sequences and its physical operators. Biorthogonal sequences {ϕn} and {ψn} in a Hilbert space H are said to be regular if Span {ϕn} and Span {ψn} are dense in H . The first purpose is to show that there exists a non-singular positive self-adjoint operator Tf in H defined by an orthonormal basis (ONB) f ≡ {fn} in H such that ϕn = Tffn and ψ n = Tf - 1 f n , n = 0, 1, …, and such an ONB f is unique. The second purpose is to define and study the lowering operators Af and Bf † , the raising operators Bf and Af † , and the number operators Nf and Nf † determined by the non-singular positive self-adjoint operator Tf. These operators connect with quasi-Hermitian quantum mechanics and its relatives. This paper clarifies and simplifies the mathematical structure of this framework and minimizes the required assumptions.
Regularity for eigenfunctions of Schr\\"{o}dinger operators
Ammann, Bernd; Nistor, Victor
2010-01-01
We prove a regularity result in weighted Sobolev spaces for the eigenfunctions of a Schroedinger operator. More precisely, let K_{a}^{m}(\\RR^{3N}) be the weighted Sobolev space obtained by blowing up the set of singular points of the Coulomb type potential V(x) = \\sum_{1 \\le j \\le N} \\frac{b_j}{|x_j|} + \\sum_{1 \\le i < j \\le N} \\frac{c_{ij}}{|x_i-x_j|}, x in R^{3N}, b_j, c_{ij} in R. If u in L^2(R^{3N}) satisfies (-\\Delta + V) u = \\lambda u in distribution sense, then u belongs to K_{a}^{m} for all m \\in Z_+ and all a \\le 0. Our result extends to the case when b_j and c_{ij} are suitable bounded functions on the blown-up space. In the single-electron, multi-nuclei case, we obtain the same result for all a<3/2.
Algebraic Structure on Dirichlet Spaces
Xing FANG; Ping HE; Jian Gang YING
2006-01-01
In this short note, we shall give a few equivalent conditions for a closed form to be Markovian, and prove that the closure of a sub-algebra of bounded functions in a Dirichlet space must be Markovian. We also study the regular representation of Dirichlet spaces and the classification of Dirichlet subspaces.
Chaotic, regular and unbounded behaviour in the elastic impact oscillator
Lamba, H
1993-01-01
A discontinuous area-preserving mapping derived from a sinusoidally-forced impacting system is studied. This system, the elastic impact oscillator, is very closely related to the accelerator models of particle physics such as the Fermi map. The discontinuity in the mapping is due to grazing which can have a surprisingly large effect upon the phase space. In particular, at the boundary of the stochastic sea, the discontinuity set and its images can act as a partial barrier which allows trajectories to move between chaotic and regular regions. The system at higher energies is also analysed and Moser's invariant curve theorem is used to find sufficient conditions for the existence of invariant curves that bound the energy of the motion. Finally the behaviour of the system under more general periodic forcing is briefly investigated.
Differential Regularization of a Non-relativistic Anyon Model
Freedman, Daniel Z; Rius, N
1994-01-01
Differential regularization is applied to a field theory of a non-relativistic charged boson field $\\phi$ with $\\lambda (\\phi {}^{*} \\phi)^2$ self-interaction and coupling to a statistics-changing $U(1)$ Chern-Simons gauge field. Renormalized configuration-space amplitudes for all diagrams contributing to the $\\phi {}^{*} \\phi {}^{*} \\phi \\phi$ 4-point function, which is the only primitively divergent Green's function, are obtained up to 3-loop order. The renormalization group equations are explicitly checked, and the scheme dependence of the $\\beta$-function is investigated. If the renormalization scheme is fixed to agree with a previous 1-loop calculation, the 2- and 3-loop contributions to $\\beta(\\lambda,e)$ vanish, and $\\beta(\\lambda,e)$ itself vanishes when the ``self-dual'' condition relating $\\lambda$ to the gauge coupling $e$ is imposed.
Regularizing Inverse Preconditioners for Symmetric Band Toeplitz Matrices
O. Menchi
2007-01-01
Full Text Available Image restoration is a widely studied discrete ill-posed problem. Among the many regularization methods used for treating the problem, iterative methods have been shown to be effective. In this paper, we consider the case of a blurring function defined by space invariant and band-limited PSF, modeled by a linear system that has a band block Toeplitz structure with band Toeplitz blocks. In order to reduce the number of iterations required to obtain acceptable reconstructions, in 13 an inverse Toeplitz preconditioner for problems with a Toeplitz structure was proposed. The cost per iteration is of O(n2logn operations, where n2 is the pixel number of the 2D image. In this paper, we propose inverse preconditioners with a band Toeplitz structure, which lower the cost to O(n2 and in experiments showed the same speed of convergence and reconstruction efficiency as the inverse Toeplitz preconditioner.
Regularizing Inverse Preconditioners for Symmetric Band Toeplitz Matrices
Lotti G
2007-01-01
Full Text Available Image restoration is a widely studied discrete ill-posed problem. Among the many regularization methods used for treating the problem, iterative methods have been shown to be effective. In this paper, we consider the case of a blurring function defined by space invariant and band-limited PSF, modeled by a linear system that has a band block Toeplitz structure with band Toeplitz blocks. In order to reduce the number of iterations required to obtain acceptable reconstructions, in 13 an inverse Toeplitz preconditioner for problems with a Toeplitz structure was proposed. The cost per iteration is of operations, where is the pixel number of the 2D image. In this paper, we propose inverse preconditioners with a band Toeplitz structure, which lower the cost to and in experiments showed the same speed of convergence and reconstruction efficiency as the inverse Toeplitz preconditioner.
Polynomial algebras Poisson with regular structure of simplectical leaf
Odesskij, A V
2002-01-01
The Poisson polynomial algebras with certain regularity conditions are studied. The linear structure on the dual spaces of the semisimple Lie algebras, the Sklyanin quadratic elliptical algebras as well as the polynomial algebras constitute, in particular, the algebras of this class. Simple determinate relations between the brackets and Kazimir operators are established. These relations determine, in particular, that the sum of the Kazimir operators grades coincides with the dimensionality of the algebra for the Sklyanin elliptical algebras. The examples of such algebras are presented and it is shown, that some of them are naturally generated in the Hamiltonian integrated systems. The new class of the two-particle integrable systems, depending elliptically both on the coordinates and pulses, is among these examples
Regularity properties of infinite-dimensional Lie groups, and semiregularity
Glockner, Helge
2012-01-01
Let G be a Lie group modelled on a locally convex space, with Lie algebra g, and k be a non-negative integer or infinity. We say that G is C^k-semiregular if each C^k-curve c in g admits a left evolution Evol(c) in G. If, moreover, the map taking c to evol(c):=Evol(c)(1) is smooth, then G is called C^k-regular. For G a C^k-semiregular Lie group and m an order of differentiability, we show that evol is C^m if and only if Evol is C^m. If evol is continuous at 0, then evol is continuous. If G is...
Optimal analysis of structures by concepts of symmetry and regularity
Kaveh, Ali
2013-01-01
Optimal analysis is defined as an analysis that creates and uses sparse, well-structured and well-conditioned matrices. The focus is on efficient methods for eigensolution of matrices involved in static, dynamic and stability analyses of symmetric and regular structures, or those general structures containing such components. Powerful tools are also developed for configuration processing, which is an important issue in the analysis and design of space structures and finite element models. Different mathematical concepts are combined to make the optimal analysis of structures feasible. Canonical forms from matrix algebra, product graphs from graph theory and symmetry groups from group theory are some of the concepts involved in the variety of efficient methods and algorithms presented. The algorithms elucidated in this book enable analysts to handle large-scale structural systems by lowering their computational cost, thus fulfilling the requirement for faster analysis and design of future complex systems. The ...
Wang, Jim Jing-Yan
2014-09-20
Nonnegative matrix factorization (NMF), a popular part-based representation technique, does not capture the intrinsic local geometric structure of the data space. Graph regularized NMF (GNMF) was recently proposed to avoid this limitation by regularizing NMF with a nearest neighbor graph constructed from the input data set. However, GNMF has two main bottlenecks. First, using the original feature space directly to construct the graph is not necessarily optimal because of the noisy and irrelevant features and nonlinear distributions of data samples. Second, one possible way to handle the nonlinear distribution of data samples is by kernel embedding. However, it is often difficult to choose the most suitable kernel. To solve these bottlenecks, we propose two novel graph-regularized NMF methods, AGNMFFS and AGNMFMK, by introducing feature selection and multiple-kernel learning to the graph regularized NMF, respectively. Instead of using a fixed graph as in GNMF, the two proposed methods learn the nearest neighbor graph that is adaptive to the selected features and learned multiple kernels, respectively. For each method, we propose a unified objective function to conduct feature selection/multi-kernel learning, NMF and adaptive graph regularization simultaneously. We further develop two iterative algorithms to solve the two optimization problems. Experimental results on two challenging pattern classification tasks demonstrate that the proposed methods significantly outperform state-of-the-art data representation methods.
D. C. Kent
1985-01-01
Full Text Available This paper is concerned with the notion of ordered Cauchy space which is given a simple internal characterization in Section 2. It gives a discription of the category of ordered Cauchy spaces which have ordered completions, and a construction of the fine completion functor on this category. Sections 4 through 6 deals with certain classes of ordered Cauchy spaces which have ordered completions; examples are given which show that the fine completion does not preserve such properties as uniformizability, regularity, or total boundedness. From these results, it is evident that a further study of ordered Cauchy completions is needed.
Motor Cortex Stimulation in Parkinson's Disease
Marisa De Rose; Giusy Guzzi; Domenico Bosco; Mary Romano; Serena Marianna Lavano; Massimiliano Plastino; Giorgio Volpentesta; Rosa Marotta; Angelo Lavano
2012-01-01
Motor Cortex Stimulation (MCS) is less efficacious than Deep Brain Stimulation (DBS) in Parkinson's disease. However, it might be proposed to patients excluded from DBS or unresponsive to DBS. Ten patients with advanced PD underwent unilateral MCS contralaterally to the worst clinical side. A plate electrode was positioned over the motor cortex in the epidural space through single burr hole after identification of the area with neuronavigation and neurophysiological tests. Clinical assessment...
Topological Logics with Connectedness over Euclidean Spaces
Kontchakov, Roman; Pratt-Hartmann, Ian; Zakharyaschev, Michael
2011-01-01
We consider the quantifier-free languages, Bc and Bc0, obtained by augmenting the signature of Boolean algebras with a unary predicate representing, respectively, the property of being connected, and the property of having a connected interior. These languages are interpreted over the regular closed sets of n-dimensional Euclidean space (n greater than 1) and, additionally, over the regular closed polyhedral sets of n-dimensional Euclidean space. The resulting logics are examples of formalisms that have recently been proposed in the Artificial Intelligence literature under the rubric "Qualitative Spatial Reasoning." We prove that the satisfiability problem for Bc is undecidable over the regular closed polyhedra in all dimensions greater than 1, and that the satisfiability problem for both languages is undecidable over both the regular closed sets and the regular closed polyhedra in the Euclidean plane. However, we also prove that the satisfiability problem for Bc0 is NP-complete over the regular closed sets i...
Convergence and fluctuations of Regularized Tyler estimators
Kammoun, Abla
2015-10-26
This article studies the behavior of regularized Tyler estimators (RTEs) of scatter matrices. The key advantages of these estimators are twofold. First, they guarantee by construction a good conditioning of the estimate and second, being a derivative of robust Tyler estimators, they inherit their robustness properties, notably their resilience to the presence of outliers. Nevertheless, one major problem that poses the use of RTEs in practice is represented by the question of setting the regularization parameter p. While a high value of p is likely to push all the eigenvalues away from zero, it comes at the cost of a larger bias with respect to the population covariance matrix. A deep understanding of the statistics of RTEs is essential to come up with appropriate choices for the regularization parameter. This is not an easy task and might be out of reach, unless one considers asymptotic regimes wherein the number of observations n and/or their size N increase together. First asymptotic results have recently been obtained under the assumption that N and n are large and commensurable. Interestingly, no results concerning the regime of n going to infinity with N fixed exist, even though the investigation of this assumption has usually predated the analysis of the most difficult N and n large case. This motivates our work. In particular, we prove in the present paper that the RTEs converge to a deterministic matrix when n → ∞ with N fixed, which is expressed as a function of the theoretical covariance matrix. We also derive the fluctuations of the RTEs around this deterministic matrix and establish that these fluctuations converge in distribution to a multivariate Gaussian distribution with zero mean and a covariance depending on the population covariance and the parameter.
Regular physical exercise: way to healthy life.
Siddiqui, N I; Nessa, A; Hossain, M A
2010-01-01
Any bodily activity or movement that enhances and maintains overall health and physical fitness is called physical exercise. Habit of regular physical exercise has got numerous benefits. Exercise is of various types such as aerobic exercise, anaerobic exercise and flexibility exercise. Aerobic exercise moves the large muscle groups with alternate contraction and relaxation, forces to deep breath, heart to pump more blood with adequate tissue oxygenation. It is also called cardiovascular exercise. Examples of aerobic exercise are walking, running, jogging, swimming etc. In anaerobic exercise, there is forceful contraction of muscle with stretching, usually mechanically aided and help to build up muscle strength and muscle bulk. Examples are weight lifting, pulling, pushing, sprinting etc. Flexibility exercise is one type of stretching exercise to improve the movements of muscles, joints and ligaments. Walking is a good example of aerobic exercise, easy to perform, safe, effective, does not require any training or equipment and less chance of injury. Regular 30 minutes brisk walking in the morning with 150 minutes per week is a good exercise. Regular exercise improves the cardiovascular status, reduces the risk of cardiac disease, high blood pressure and cerebrovascular disease. It reduces body weight, improves insulin sensitivity, helps in glycemic control, prevents obesity and diabetes mellitus. It is helpful for relieving anxiety, stress, brings a sense of well being and overall physical fitness. Global trend is mechanization, labor savings and leading to epidemic of long term chronic diseases like diabetes mellitus, cardiovascular diseases etc. All efforts should be made to create public awareness promoting physical activity, physically demanding recreational pursuits and providing adequate facilities.
Flemming, Jens; Hofmann, Bernd
2011-08-01
In this paper, we enlighten the role of variational inequalities for obtaining convergence rates in Tikhonov regularization of nonlinear ill-posed problems with convex penalty functionals under convexity constraints in Banach spaces. Variational inequalities are able to cover solution smoothness and the structure of nonlinearity in a uniform manner, not only for unconstrained but, as we indicate, also for constrained Tikhonov regularization. In this context, we extend the concept of projected source conditions already known in Hilbert spaces to Banach spaces, and we show in the main theorem that such projected source conditions are to some extent equivalent to certain variational inequalities. The derived variational inequalities immediately yield convergence rates measured by Bregman distances.
Invariant Regularization of Supersymmetric Chiral Gauge Theory
Suzuki, H
1999-01-01
We present a regularization scheme which respects the supersymmetry and the maximal background gauge covariance in supersymmetric chiral gauge theories. When the anomaly cancellation condition is satisfied, the effective action in the superfield background field method automatically restores the gauge invariance without counterterms. The scheme also provides a background gauge covariant definition of composite operators that is especially useful in analyzing anomalies. We present several applications: The minimal consistent gauge anomaly; the super-chiral anomaly and the superconformal anomaly; as the corresponding anomalous commutators, the Konishi anomaly and an anomalous supersymmetric transformation law of the supercurrent (the ``central extension'' of N=1 supersymmetry algebra) and of the R-current.
Total-variation regularization with bound constraints
Chartrand, Rick [Los Alamos National Laboratory; Wohlberg, Brendt [Los Alamos National Laboratory
2009-01-01
We present a new algorithm for bound-constrained total-variation (TV) regularization that in comparison with its predecessors is simple, fast, and flexible. We use a splitting approach to decouple TV minimization from enforcing the constraints. Consequently, existing TV solvers can be employed with minimal alteration. This also makes the approach straightforward to generalize to any situation where TV can be applied. We consider deblurring of images with Gaussian or salt-and-pepper noise, as well as Abel inversion of radiographs with Poisson noise. We incorporate previous iterative reweighting algorithms to solve the TV portion.
Regularizing mappings of Lévy measures
Barndorff-Nielsen, Ole Eiler; Thorbjørnsen, Steen
2006-01-01
In this paper we introduce and study a regularizing one-to-one mapping from the class of one-dimensional Lévy measures into itself. This mapping appeared implicitly in our previous paper [O.E. Barndorff-Nielsen, S. Thorbjørnsen, A connection between free and classical infinite divisibility, Inf....... Dim. Anal. Quant. Probab. 7 (2004) 573–590], where we introduced a one-to-one mapping from the class of one-dimensional infinitely divisible probability measures into itself. Based on the investigation of in the present paper, we deduce further properties of . In particular it is proved that maps...
Multichannel image regularization using anisotropic geodesic filtering
Grazzini, Jacopo A [Los Alamos National Laboratory
2010-01-01
This paper extends a recent image-dependent regularization approach introduced in aiming at edge-preserving smoothing. For that purpose, geodesic distances equipped with a Riemannian metric need to be estimated in local neighbourhoods. By deriving an appropriate metric from the gradient structure tensor, the associated geodesic paths are constrained to follow salient features in images. Following, we design a generalized anisotropic geodesic filter; incorporating not only a measure of the edge strength, like in the original method, but also further directional information about the image structures. The proposed filter is particularly efficient at smoothing heterogeneous areas while preserving relevant structures in multichannel images.
Homology of powers of regular ideals
2003-01-01
For a commutative ring R with an ideal I, generated by a finite regular sequence, we construct differential graded algebras which provide R-free resolutions of I^s and of R/I^s for s>0 and which generalise the Koszul resolution. We derive these from a certain multiplicative double complex. By means of a Cartan-Eilenberg spectral sequence we express Tor_*^R(R/I,R/I^s) and Tor_*^R(R/I, I^s) in terms of exact sequences and find that they are free as R/I-modules. Except for R/I, their product str...
The regular state in higher order gravity
Cotsakis, Spiros; Kadry, Seifedine; Trachilis, Dimitrios
2016-08-01
We consider the higher-order gravity theory derived from the quadratic Lagrangian R + 𝜖R2 in vacuum as a first-order (ADM-type) system with constraints, and build time developments of solutions of an initial value formulation of the theory. We show that all such solutions, if analytic, contain the right number of free functions to qualify as general solutions of the theory. We further show that any regular analytic solution which satisfies the constraints and the evolution equations can be given in the form of an asymptotic formal power series expansion.
Regular collision of dilatonic inflating branes
Leeper, E; Maartens, R
2005-01-01
We demonstrate that a two brane system with a bulk scalar field driving power-law inflation on the branes has an instability in the radion. We solve for the resulting trajectory of the brane, and find that the instability can lead to collision. Brane quantities such as the scale factor are shown to be regular at this collision. In addition we describe the system using a low energy expansion. The low energy expansion accurately reproduces the known exact solution, but also identifies an alternative solution for the bulk metric and brane trajectory.
Two-pass greedy regular expression parsing
Grathwohl, Niels Bjørn Bugge; Henglein, Fritz; Nielsen, Lasse;
2013-01-01
We present new algorithms for producing greedy parses for regular expressions (REs) in a semi-streaming fashion. Our lean-log algorithm executes in time O(mn) for REs of size m and input strings of size n and outputs a compact bit-coded parse tree representation. It improves on previous algorithms......-based prototype indicates that the superior performance of our lean-log algorithm can also be observed in practice; it is also surprisingly competitive with RE tools not performing full parsing, such as Grep....
Boesveldt, N.F.
2016-01-01
WISES are social enterprises that work with people marginalized from the regular labour market, including people with severe handicaps, with disabilities and those who suffer addiction and homelessness. WISES offer an alternative to regular social programs: they breach social exclusion and stimulate
Vovk, Uros; Pernus, Franjo; Likar, Bostjan
2003-05-01
In MRI, image intensity non-uniformity is an adverse phenomenon that increases inter-tissue overlapping. The aim of this study was to provide a novel general framework, named regularized feature condensing (RFC), for condensing the distribution of image features and apply it to correct intensity non-uniformity via spatial regularization. The proposed RCF method is an iterative procedure, which consists of four basic steps. First, creation of a feature space, which consists of multi-spectral image intensities and corresponding second derivatives. Second, estimation of the intensity condensing map in feature space, i.e. the estimation of the increase of feature probability densities by a well-established mean shift procedure. Third, regularization of intensity condensing map in image space, which yields the estimation of intensity non-uniformity. Fourth, applying the estimation of non-uniformity correction to the input image. In this way, the intensity distributions of distinct tissues are gradually condensed via spatial regularization. The method was tested on simulated and real MR brain images for which gold standard segmentations were available. The results showed that the method did not induce additional intensity variations in simulated uniform images and efficiently removed intensity non-uniformity in real MR brain images. The proposed RCF method is a powerful fully automated intensity non-uniformity correction method that makes no a prior assumptions on the image intensity distribution and provides non-parametric non-uniformity correction.
Sparsity-based Image Error Concealment via Adaptive Dual Dictionary Learning and Regularization.
Liu, Xianming; Zhai, Deming; Zhou, Jiantao; Wang, Shiqi; Zhao, Debin; Gao, Huijun
2016-10-31
In this paper, we propose a novel sparsity-based image error concealment (EC) algorithm through Adaptive Dual dictionary Learning and Regularization (ADLR). We define two feature spaces: the observed space and the latent space, corresponding to the available regions and the missing regions of image under test, respectively. We learn adaptive and complete dictionaries individually for each space, where the training data are collected via an adaptive template matching mechanism. Based on the piecewise stationarity of natural images, a local correlation model is learned to bridge the sparse representations of the aforementioned dual spaces, allowing us to transfer the knowledge of the available regions to the missing regions for EC purpose. Eventually, the EC task is formulated as a unified optimization problem, where the sparsity of both spaces and the learned correlation model are incorporated. Experimental results show that the proposed method outperforms the state-of-the-art techniques in terms of both objective and perceptual metrics.
UNIVERSAL REGULAR AUTONOMOUS ASYNCHRONOUS SYSTEMS: ω-LIMIT SETS, INVARIANCE AND BASINS OF ATTRACTION
Serban Vlad
2011-07-01
Full Text Available The asynchronous systems are the non-deterministic real timebinarymodels of the asynchronous circuits from electrical engineering.Autonomy means that the circuits and their models have no input.Regularity means analogies with the dynamical systems, thus such systems may be considered to be real time dynamical systems with a’vector field’, Universality refers to the case when the state space of the system is the greatest possible in the sense of theinclusion. The purpose of this paper is that of defining, by analogy with the dynamical systems theory, the omega-limit sets, the invariance and the basins of attraction of the universal regular autonomous asynchronous systems.
Partial regularity of weak solutions for Landau-Lifshitz system with potential
CHU YuMing; LIU XianGao
2009-01-01
In this note, we prove the partial regularity of stationary weak solutions for the Landau-Lifshitz system with general potential in four or three dimensional space. As well known, in general, since the constraint of the methods, in order to get the partial regularity of stationary weak solution of the Landau-Lifshitz system with potential, we need to add some very strongly conditions on the potential. The main difficulty caused by potential is how to find the equation satisfied by the scaling function, which breaks down the blow-up processing. We estimate directly Morrey's energy to avoid the difficulties by blowing up.
Partial regularity of weak solutions for Landau-Lifshitz system with potential
2009-01-01
In this note, we prove the partial regularity of stationary weak solutions for the Landau- Lifshitz system with general potential in four or three dimensional space. As well known, in general, since the constraint of the methods, in order to get the partial regularity of stationary weak solution of the Landau-Lifshitz system with potential, we need to add some very strongly conditions on the potential. The main difficulty caused by potential is how to find the equation satisfied by the scaling function, which breaks down the blow-up processing. We estimate directly Morrey’s energy to avoid the difficulties by blowing up.
Shen, Wenxian; Shen, Zhongwei
2017-03-01
The present paper is devoted to the investigation of various properties of transition fronts in one-dimensional nonlocal equations in heterogeneous media of ignition type, whose existence has been established by the authors of the present paper in a previous work. It is first shown that transition fronts are continuously differentiable in space with uniformly bounded and uniformly Lipschitz continuous space partial derivative. This is the first time that space regularity of transition fronts in nonlocal equations is ever studied. It is then shown that transition fronts are uniformly steep. Finally, asymptotic stability, in the sense of exponentially attracting front-like initial data, of transition fronts is studied.
Accretion onto some well-known regular black holes
Jawad, Abdul; Shahzad, M.U. [COMSATS Institute of Information Technology, Department of Mathematics, Lahore (Pakistan)
2016-03-15
In this work, we discuss the accretion onto static spherically symmetric regular black holes for specific choices of the equation of state parameter. The underlying regular black holes are charged regular black holes using the Fermi-Dirac distribution, logistic distribution, nonlinear electrodynamics, respectively, and Kehagias-Sftesos asymptotically flat regular black holes. We obtain the critical radius, critical speed, and squared sound speed during the accretion process near the regular black holes. We also study the behavior of radial velocity, energy density, and the rate of change of the mass for each of the regular black holes. (orig.)
Accretion onto Some Well-Known Regular Black Holes
Jawad, Abdul
2016-01-01
In this work, we discuss the accretion onto static spherical symmetric regular black holes for specific choices of equation of state parameter. The underlying regular black holes are charged regular black hole using Fermi-Dirac Distribution, logistic distribution, nonlinear electrodynamics, respectively and Kehagias-Sftesos asymptotically flat regular black hole. We obtain the critical radius, critical speed and squared sound speed during the accretion process near the regular black holes. We also study the behavior of radial velocity, energy density and rate of change of mass for each regular black holes.
... is preferred by many doctors, patients and families. Vagus Nerve Stimulation Vagus nerve stimulation (VNS) works through a device implanted under ... skin that sends electrical pulses through the left vagus nerve, half of a prominent pair of nerves that ...
Feldspar, Infrared Stimulated Luminescence
Jain, Mayank
2014-01-01
This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars.......This entry primarily concerns the characteristics and the origins of infrared-stimulated luminescence in feldspars....
Multiple graph regularized nonnegative matrix factorization
Wang, Jim Jing-Yan
2013-10-01
Non-negative matrix factorization (NMF) has been widely used as a data representation method based on components. To overcome the disadvantage of NMF in failing to consider the manifold structure of a data set, graph regularized NMF (GrNMF) has been proposed by Cai et al. by constructing an affinity graph and searching for a matrix factorization that respects graph structure. Selecting a graph model and its corresponding parameters is critical for this strategy. This process is usually carried out by cross-validation or discrete grid search, which are time consuming and prone to overfitting. In this paper, we propose a GrNMF, called MultiGrNMF, in which the intrinsic manifold is approximated by a linear combination of several graphs with different models and parameters inspired by ensemble manifold regularization. Factorization metrics and linear combination coefficients of graphs are determined simultaneously within a unified object function. They are alternately optimized in an iterative algorithm, thus resulting in a novel data representation algorithm. Extensive experiments on a protein subcellular localization task and an Alzheimer\\'s disease diagnosis task demonstrate the effectiveness of the proposed algorithm. © 2013 Elsevier Ltd. All rights reserved.
Regularized Semiparametric Estimation for Ordinary Differential Equations.
Li, Yun; Zhu, Ji; Wang, Naisyin
2015-07-01
Ordinary differential equations (ODEs) are widely used in modeling dynamic systems and have ample applications in the fields of physics, engineering, economics and biological sciences. The ODE parameters often possess physiological meanings and can help scientists gain better understanding of the system. One key interest is thus to well estimate these parameters. Ideally, constant parameters are preferred due to their easy interpretation. In reality, however, constant parameters can be too restrictive such that even after incorporating error terms, there could still be unknown sources of disturbance that lead to poor agreement between observed data and the estimated ODE system. In this paper, we address this issue and accommodate short-term interferences by allowing parameters to vary with time. We propose a new regularized estimation procedure on the time-varying parameters of an ODE system so that these parameters could change with time during transitions but remain constants within stable stages. We found, through simulation studies, that the proposed method performs well and tends to have less variation in comparison to the non-regularized approach. On the theoretical front, we derive finite-sample estimation error bounds for the proposed method. Applications of the proposed method to modeling the hare-lynx relationship and the measles incidence dynamic in Ontario, Canada lead to satisfactory and meaningful results.
Tomographic laser absorption spectroscopy using Tikhonov regularization.
Guha, Avishek; Schoegl, Ingmar
2014-12-01
The application of tunable diode laser absorption spectroscopy (TDLAS) to flames with nonhomogeneous temperature and concentration fields is an area where only few studies exist. Experimental work explores the performance of tomographic reconstructions of species concentration and temperature profiles from wavelength-modulated TDLAS measurements within the plume of an axisymmetric McKenna burner. Water vapor transitions at 1391.67 and 1442.67 nm are probed using calibration-free wavelength modulation spectroscopy with second harmonic detection (WMS-2f). A single collimated laser beam is swept parallel to the burner surface, where scans yield pairs of line-of-sight (LOS) data at multiple radial locations. Radial profiles of absorption data are reconstructed using Tikhonov regularized Abel inversion, which suppresses the amplification of experimental noise that is typically observed for reconstructions with high spatial resolution. Based on spectral data reconstructions, temperatures and mole fractions are calculated point-by-point. Here, a least-squares approach addresses difficulties due to modulation depths that cannot be universally optimized due to a nonuniform domain. Experimental results show successful reconstructions of temperature and mole fraction profiles based on two-transition, nonoptimally modulated WMS-2f and Tikhonov regularized Abel inversion, and thus validate the technique as a viable diagnostic tool for flame measurements.
Regularized multiple criteria linear programs for classification
SHI Yong; TIAN YingJie; CHEN XiaoJun; ZHANG Peng
2009-01-01
Although multiple criteria mathematical program (MCMP), as an alternative method of classification, has been used in various real-life data mining problems, its mathematical structure of solvability is still challengeable. This paper proposes a regularized multiple criteria linear program (RMCLP) for two classes of classification problems. It first adds some regularization terms in the objective function of the known multiple criteria linear program (MCLP) model for possible existence of solution. Then the paper describes the mathematical framework of the solvability. Finally, a series of experimental tests are conducted to illustrate the performance of the proposed RMCLP with the existing methods: MCLP, multiple criteria quadratic program (MCQP), and support vector machine (SVM). The results of four publicly available datasets and a real-life credit dataset all show that RMCLP is a competitive method in classification. Furthermore, this paper explores an ordinal RMCLP (ORMCLP) model for ordinal multi-group problems. Comparing ORMCLP with traditional methods such as One-Against-One, One-Against-The rest on large-scale credit card dataset, experimental results show that both ORMCLP and RMCLP perform well.
Supporting Regularized Logistic Regression Privately and Efficiently.
Wenfa Li
Full Text Available As one of the most popular statistical and machine learning models, logistic regression with regularization has found wide adoption in biomedicine, social sciences, information technology, and so on. These domains often involve data of human subjects that are contingent upon strict privacy regulations. Concerns over data privacy make it increasingly difficult to coordinate and conduct large-scale collaborative studies, which typically rely on cross-institution data sharing and joint analysis. Our work here focuses on safeguarding regularized logistic regression, a widely-used statistical model while at the same time has not been investigated from a data security and privacy perspective. We consider a common use scenario of multi-institution collaborative studies, such as in the form of research consortia or networks as widely seen in genetics, epidemiology, social sciences, etc. To make our privacy-enhancing solution practical, we demonstrate a non-conventional and computationally efficient method leveraging distributing computing and strong cryptography to provide comprehensive protection over individual-level and summary data. Extensive empirical evaluations on several studies validate the privacy guarantee, efficiency and scalability of our proposal. We also discuss the practical implications of our solution for large-scale studies and applications from various disciplines, including genetic and biomedical studies, smart grid, network analysis, etc.
Supporting Regularized Logistic Regression Privately and Efficiently.
Li, Wenfa; Liu, Hongzhe; Yang, Peng; Xie, Wei
2016-01-01
As one of the most popular statistical and machine learning models, logistic regression with regularization has found wide adoption in biomedicine, social sciences, information technology, and so on. These domains often involve data of human subjects that are contingent upon strict privacy regulations. Concerns over data privacy make it increasingly difficult to coordinate and conduct large-scale collaborative studies, which typically rely on cross-institution data sharing and joint analysis. Our work here focuses on safeguarding regularized logistic regression, a widely-used statistical model while at the same time has not been investigated from a data security and privacy perspective. We consider a common use scenario of multi-institution collaborative studies, such as in the form of research consortia or networks as widely seen in genetics, epidemiology, social sciences, etc. To make our privacy-enhancing solution practical, we demonstrate a non-conventional and computationally efficient method leveraging distributing computing and strong cryptography to provide comprehensive protection over individual-level and summary data. Extensive empirical evaluations on several studies validate the privacy guarantee, efficiency and scalability of our proposal. We also discuss the practical implications of our solution for large-scale studies and applications from various disciplines, including genetic and biomedical studies, smart grid, network analysis, etc.
Supporting Regularized Logistic Regression Privately and Efficiently
Li, Wenfa; Liu, Hongzhe; Yang, Peng; Xie, Wei
2016-01-01
As one of the most popular statistical and machine learning models, logistic regression with regularization has found wide adoption in biomedicine, social sciences, information technology, and so on. These domains often involve data of human subjects that are contingent upon strict privacy regulations. Concerns over data privacy make it increasingly difficult to coordinate and conduct large-scale collaborative studies, which typically rely on cross-institution data sharing and joint analysis. Our work here focuses on safeguarding regularized logistic regression, a widely-used statistical model while at the same time has not been investigated from a data security and privacy perspective. We consider a common use scenario of multi-institution collaborative studies, such as in the form of research consortia or networks as widely seen in genetics, epidemiology, social sciences, etc. To make our privacy-enhancing solution practical, we demonstrate a non-conventional and computationally efficient method leveraging distributing computing and strong cryptography to provide comprehensive protection over individual-level and summary data. Extensive empirical evaluations on several studies validate the privacy guarantee, efficiency and scalability of our proposal. We also discuss the practical implications of our solution for large-scale studies and applications from various disciplines, including genetic and biomedical studies, smart grid, network analysis, etc. PMID:27271738
Mohd. Suhaib Kidwai; Mohd Maroof Siddiqui; Ahmad Nafees; Qazi saeed Ahmad
2012-01-01
This paper aims to bring forth the significance of stimulators , recent advancements in the field of stimulators and how electrical signals can be utilized for pain relief and to cure other diseases of human body ,by using stimulators. This paper aims to create awareness about stimulators and also focuses on their advantages as compared to theconventional medicine .Moreover,it also bring forth that how an electrical signal can be utilized for treating various human disorders and diseases.
A REGULAR VALUE OF COMPACT DEFORMATION
J.M.Soriano
2006-01-01
Sufficient conditions were given to assert that between any two Banach spaces over K, Fredholm mappings share at least one value in a specific open ball. The proof of the result is constructive and based upon continuation methods.
Huang, Jian; Hu, Weidong; Ghogho, Mounir; Xin, Qin; Du, Xiaoyong; Guo, Weiwei
2012-12-01
The increase in space debris can seriously threaten regular activities in the Low Earth Orbit (LEO) environment. Therefore, it is necessary to develop robust, efficient and reliable techniques to understand the potential motions of the LEO debris. In this paper, we propose a novel signal processing approach to detect and estimate the motions of LEO space debris that is based on a fence-type space surveillance radar system. Because of the sparse distribution of the orbiting debris through the fence in our observations, we formulate the signal detection and the motion parameter estimation as a sparse signal reconstruction problem with respect to an over-complete dictionary. Moreover, we propose a new scheme to reduce the size of the original over-complete dictionary without the loss of the important information. This new scheme is based on a careful analysis of the relations between the acceleration and the directions of arrival for the corresponding LEO space debris. Our simulation results show that the proposed approach can achieve extremely good performance in terms of the accuracy for detection and estimation. Furthermore, our simulation results demonstrate the robustness of the approach in scenarios with a low Signal-to-Noise Ratio (SNR) and the super-resolution properties. We hope our signal processing approach can stimulate further work on monitoring LEO space debris.
On Some General Regularities of Formation of the Planetary Systems
Belyakov A. V.
2014-01-01
Full Text Available J.Wheeler’s geometrodynamic concept has been used, in which space continuum is considered as a topologically non-unitary coherent surface admitting the existence of transitions of the input-output kind between distant regions of the space in an additional dimension. This model assumes the existence of closed structures (micro- and macro- contours formed due to the balance between main interactions: gravitational, electric, magnetic, and inertial forces. It is such macrocontours that have been demonstrated to form — independently of their material basis — the essential structure of objects at various levels of organization of matter. On the basis of this concept in this paper basic regularities acting during formation planetary systems have been obtained. The existence of two sharply different types of planetary systems has been determined. The dependencies linking the masses of the planets, the diameters of the planets, the orbital radii of the planet, and the mass of the central body have been deduced. The possibility of formation of Earth-like planets near brown dwarfs has been grounded. The minimum mass of the planet, which may arise in the planetary system, has been defined.
Multiple Kernel Learning for adaptive graph regularized nonnegative matrix factorization
Wang, Jim Jing-Yan
2012-01-01
Nonnegative Matrix Factorization (NMF) has been continuously evolving in several areas like pattern recognition and information retrieval methods. It factorizes a matrix into a product of 2 low-rank non-negative matrices that will define parts-based, and linear representation of non-negative data. Recently, Graph regularized NMF (GrNMF) is proposed to find a compact representation, which uncovers the hidden semantics and simultaneously respects the intrinsic geometric structure. In GNMF, an affinity graph is constructed from the original data space to encode the geometrical information. In this paper, we propose a novel idea which engages a Multiple Kernel Learning approach into refining the graph structure that reflects the factorization of the matrix and the new data space. The GrNMF is improved by utilizing the graph refined by the kernel learning, and then a novel kernel learning method is introduced under the GrNMF framework. Our approach shows encouraging results of the proposed algorithm in comparison to the state-of-the-art clustering algorithms like NMF, GrNMF, SVD etc.
Regular black holes and noncommutative geometry inspired fuzzy sources
Kobayashi, Shinpei
2016-05-01
We investigated regular black holes with fuzzy sources in three and four dimensions. The density distributions of such fuzzy sources are inspired by noncommutative geometry and given by Gaussian or generalized Gaussian functions. We utilized mass functions to give a physical interpretation of the horizon formation condition for the black holes. In particular, we investigated three-dimensional BTZ-like black holes and four-dimensional Schwarzschild-like black holes in detail, and found that the number of horizons is related to the space-time dimensions, and the existence of a void in the vicinity of the center of the space-time is significant, rather than noncommutativity. As an application, we considered a three-dimensional black hole with the fuzzy disc which is a disc-shaped region known in the context of noncommutative geometry as a source. We also analyzed a four-dimensional black hole with a source whose density distribution is an extension of the fuzzy disc, and investigated the horizon formation condition for it.
Supplementary Auditory and Vestibular Stimulation: Effects on Institutionalized Infants
Casler, Lawrence
1975-01-01
Supplementary stimulation was supplied for 30 minutes per day for approximately six weeks to 156 normal, full-term institutionalized infants prior to adoption. The Gesell Developmental Schedules were administered regularly (until age 27 months), to determine whether development had been enhanced by the treatment. (JMB)
COUNTING ROOTED NEAR-4-REGULAR EULERIAN MAPS ON SOME SURFACES
RenHan; LiuYanpei
1999-01-01
In this article the rooted planar near-4-regular Eulerian trails are enumerated and an explicit formula for such maps is presented. Further, the rooted near-4-regular Eulerian maps on the torus are counted in an exact way.
A distance regular graph of type E1 Ed
无
2000-01-01
In this note, the distance regular graph of type E1 Ed is considered and some characterization of the type graph is given. The results generalize the characterization of tight distance regular graphs.