Thu, 24 Jul 2008 23:19:27 BST CiteULike: Tag gauss http://www.citeulike.org/tag/gauss CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/waitonhill/article/1270300 <i>The Journal of Chemical Physics, Vol. 126, No. 9. (2007)</i><br /><br />We describe a model for the thermodynamics and dynamics of glass-forming liquids in terms of excitations from an ideal glass state to a Gaussian manifold of configurationally excited states. The quantitative fit of this three parameter model to the experimental data on excess entropy and heat capacity shows that “fragile” behavior, indicated by a sharply rising excess heat capacity as the glass transition is approached from above, occurs in anticipation of a first-order transition—usually hidden below the glass transition—to a “strong” liquid state of low excess entropy. The distinction between fragile and strong behavior of glass formers is traced back to an order of magnitude difference in the Gaussian width of their excitation energies. Simple relations connect the excess heat capacity to the Gaussian width parameter, and the liquid-liquid transition temperature, and strong, testable, predictions concerning the distinct properties of energy landscape for fragile liquids are made. The dynamic model relates relaxation to a hierarchical sequence of excitation events each involving the probability of accumulating sufficient kinetic energy on a separate excitable unit. Super-Arrhenius behavior of the relaxation rates, and the known correlation of kinetic with thermodynamic fragility, both follow from the way the rugged landscape induces fluctuations in the partitioning of energy between vibrational and configurational manifolds. A relation is derived in which the configurational heat capacity, rather than the configurational entropy of the Adam–Gibbs equation, controls the temperature dependence of the relaxation times, and this gives a comparable account of the experimental observations without postulating a divergent length scale. The familiar coincidence of zero mobility and Kauzmann temperatures is obtained as an approximate extrapolation of the theoretical equations. The comparison of the fits to excess thermodynamic properties of laboratory glass formers, and to configurational thermodynamics from simulations, reveals that the major portion of the excitation entropy responsible for fragile behavior resides in the low-frequency vibrational density of states. The thermodynamic transition predicted for fragile liquids emerges from beneath the glass transition in case of laboratory water and the unusual heat capacity behavior observed for this much studied liquid can be closely reproduced by the model. ©2007 American Institute of Physics Gaussian excitations model for glass-former dynamics and thermodynamics Dmitry Matyushov Austen Angell doi:10.1063/1.2538712 The Journal of Chemical Physics, Vol. 126, No. 9. (2007) 2007-05-01T15:20:51-00:00 2007 The Journal of Chemical Physics 126 9 AIP gauss glass-former http://www.citeulike.org/user/tyler/article/2755980 <i>Computer Vision, 2003. Proceedings. Ninth IEEE International Conference on (2003), pp. 664-671 vol.1.</i><br /><br />Evaluating sums of multivariate Gaussians is a common computational task in computer vision and pattern recognition, including in the general and powerful kernel density estimation technique. The quadratic computational complexity of the summation is a significant barrier to the scalability of this algorithm to practical applications. The fast Gauss transform (FGT) has successfully accelerated the kernel density estimation to linear running time for low-dimensional problems. Unfortunately, the cost of a direct extension of the FGT to higher-dimensional problems grows exponentially with dimension, making it impractical for dimensions above 3. We develop an improved fast Gauss transform to efficiently estimate sums of Gaussians in higher dimensions, where a new multivariate expansion scheme and an adaptive space subdivision technique dramatically improve the performance. The improved FGT has been applied to the mean shift algorithm achieving linear computational complexity. Experimental results demonstrate the efficiency and effectiveness of our algorithm. Improved fast gauss transform and efficient kernel density estimation C Yang R Duraiswami NA Gumerov L Davis doi:10.1109/ICCV.2003.1238383 Computer Vision, 2003. Proceedings. Ninth IEEE International Conference on (2003), pp. 664-671 vol.1. 2008-05-05T10:23:10-00:00 2003 Computer Vision, 2003. Proceedings. Ninth IEEE International Conference on 664 671 vol.1 density estimation fast gauss kernel nonparametric transform http://www.citeulike.org/user/tyler/article/2755972 <i>Pattern Analysis and Machine Intelligence, IEEE Transactions on, Vol. 25, No. 11. (2003), pp. 1499-1504.</i><br /><br />Many vision algorithms depend on the estimation of a probability density function from observations. Kernel density estimation techniques are quite general and powerful methods for this problem, but have a significant disadvantage in that they are computationally intensive. In this paper, we explore the use of kernel density estimation with the fast Gauss transform (FGT) for problems in vision. The FGT allows the summation of a mixture of ill Gaussians at N evaluation points in O(M+N) time, as opposed to O(MN) time for a naive evaluation and can be used to considerably speed up kernel density estimation. We present applications of the technique to problems from image segmentation and tracking and show that the algorithm allows application of advanced statistical techniques to solve practical vision problems in real-time with today's computers. Efficient kernel density estimation using the fast gauss transform with applications to color modeling and tracking A Elgammal R Duraiswami LS Davis doi:10.1109/TPAMI.2003.1240123 Pattern Analysis and Machine Intelligence, IEEE Transactions on, Vol. 25, No. 11. (2003), pp. 1499-1504. 2008-05-05T10:20:32-00:00 2003 Pattern Analysis and Machine Intelligence, IEEE Transactions on 25 11 1499 1504 density efficient estimation fast gauss kernel transform http://www.citeulike.org/user/twenta/article/2231757 <i>J. Biol. Chem., Vol. 279, No. 49. (3 December 2004), pp. 50915-50922.</i><br /><br />Proteomics of membrane proteins is essential for the understanding of cellular function. However, mass spectrometric analysis of membrane proteomes has been less successful than the proteomic determination of soluble proteins. To elucidate the mystery of transmembrane proteins in mass spectrometry, we present a detailed statistical analysis of experimental data derived from chloroplast membranes. This approach was further accomplished by the analysis of the Arabidopsis thaliana proteome after in silico digestion. We demonstrate that both the length and the hydrophobicity of the proteolytic fragments containing transmembrane segments are major determinants for detection by mass spectrometry. Based on a comparative analysis, we discuss possibilities to overcome the problem and provide possible protocols to shift the hydrophobicity of transmembrane segment-containing peptides to facilitate their detection. 10.1074/jbc.M405875200 Hiding behind Hydrophobicity: TRANSMEMBRANE SEGMENTS IN MASS SPECTROMETRY Lutz Eichacker Bernhard Granvogl Oliver Mirus Bernd Muller Christian Miess Enrico Schleiff doi:10.1074/jbc.M405875200 J. Biol. Chem., Vol. 279, No. 49. (3 December 2004), pp. 50915-50922. 2008-01-14T20:01:34-00:00 2004 J. Biol. Chem. 279 49 50915 50922 gauss gravy http://www.citeulike.org/user/tmolinier/article/439363 <i>Pattern Recognition, 2004. ICPR 2004. Proceedings of the 17th International Conference on, Vol. 3 (2004), pp. 24-27 Vol.3.</i><br /><br />A new criterion based on Gaussian fields is introduced and applied to the task of automatic rigid registration of point-sets. The method defines a simple energy function, which is always differentiable and convex in a large neighborhood of the alignment parameters; allowing for the use of powerful standard optimization techniques. We show that the size of the region of convergence can be extended so that no close initialization is needed, thus overcoming local convergence problems of iterative closest point algorithms. Furthermore, the Gaussian energy function can be evaluated with the linear complexity using the fast Gauss transform, which permits efficient implementation of the registration algorithm. Analysis through several experimental results on real world datasets shows the practicality and points out the limits of the approach. Gaussian energy functions for registration without correspondences F Boughorbel A Koschan B Abidi M Abidi Pattern Recognition, 2004. ICPR 2004. Proceedings of the 17th International Conference on, Vol. 3 (2004), pp. 24-27 Vol.3. 2005-12-16T09:59:36-00:00 2004 Pattern Recognition, 2004. ICPR 2004. Proceedings of the 17th International Conference on 3 24 27 Vol.3 gauss registration http://www.citeulike.org/user/tmolinier/article/576734 <i></i><br /><br />This paper introduces a new and simple criterion forrig# reg-ITzBAxU based on Gaussian #elds. The criterion is always di#erentiable and convex in alarg neigxBAxqU# of thealig-TIx parameters;allowing for the use of well-proven optimization techniques.Using this method we can extend the size of thereg#z ofconvergAxz so that no close initialization is needed, thus overcoming local convergxBA problems of Iterative Closest PointalgB#I#TzB Furthermore, the Gaussianenerg function can... Gaussian fields: a new criterion for 3D rigid registration Faysal Boughorbel Andreas Koschan Besma Abidi Mong Abidi 2006-04-05T12:36:41-00:00 gauss registration http://www.citeulike.org/user/sas/article/2152011 <i>The Journal of Chemical Physics, Vol. 74, No. 3. (1981), pp. 2039-2048.</i> Topological distribution functions and the second virial coefficients of ring polymers Kazuyoshi Iwata Tsunehisa Kimura The Journal of Chemical Physics, Vol. 74, No. 3. (1981), pp. 2039-2048. 2007-12-20T15:09:03-00:00 1981 The Journal of Chemical Physics 74 3 2039 2048 AIP gauss linking ring second topological virial http://www.citeulike.org/user/NitinCR/article/1979116 <i>(30 January 2006)</i><br /><br />The author narrates the life of Carl Friedrich Gauss, the 18th century mathematician, from his prodigious childhood to his extraordinary achievements that earned him the title "Prince of Mathematics". Along the way, the author introduces her readers to a different culture, the era of small states in Germany where advancement on merits, such as Gauss, was supported by enlightened rulers, competing for intellectual excellence and economic advantage through scientific progress in their small states. Based on extensive research of original and secondary sources, the author has created an historical narrative that will inspire young readers and even curious adults with a story full of human touch and personal achievement. Prince of Mathematics: Carl Friedrich Gauss MBW Tent (30 January 2006) 2007-11-25T12:42:28-00:00 2006 A K Peters Ltd biographical gauss mathematics http://www.citeulike.org/user/NitinCR/article/2658183 <i>(05 January 1987)</i> Gauss: A Biographical Study WK Bühler (05 January 1987) 2008-04-11T15:29:04-00:00 1987 Springer biographical gauss http://www.citeulike.org/user/michaelbussmann/article/2861816 <i>Journal of Computational Physics, Vol. 85, No. 2. (December 1989), pp. 503-503.</i> An analysis and optimization of the pseudo-current method Dale Nielsen Adam Drobot doi:10.1016/0021-9991(89)90169-1 Journal of Computational Physics, Vol. 85, No. 2. (December 1989), pp. 503-503. 2008-06-04T16:27:03-00:00 1989 Journal of Computational Physics 85 2 503 503 algorithm gauss law particle-in-cell pic pseudo-current simulation http://www.citeulike.org/user/michaelbussmann/article/2861770 <i>Journal of Computational Physics, Vol. 89, No. 1. (July 1990), pp. 31-40.</i><br /><br />The pseudo-current method proposed by B. Marder for eliminating charge conservation errors in electromagnetic particle-in-cell codes has been analyzed and extended. The new method has been shown to be effective and efficient in removing high frequency, short wavelength errors caused by the choice of charge deposition algorithms. To maintain the physical properties of the electromagnetic field the choice of the free parameter in the originally proposed method has been restricted. It is found that the parameter should be homogeneous spatially and that an error minimization technique can be used to determine its value. A comparison is made between this adaptive pseudo-current method and the effects of spatial smoothing on the transverse and longitudinal components of the electromagnetic field. An analysis and optimization of the pseudo-current method Nielsen Adam Drobot doi:10.1016/0021-9991(90)90115-H Journal of Computational Physics, Vol. 89, No. 1. (July 1990), pp. 31-40. 2008-06-04T16:06:53-00:00 1990 Journal of Computational Physics 89 1 31 40 algorithm gauss law particle-in-cell pic pseudo-current simulation http://www.citeulike.org/user/michaelbussmann/article/2861798 <i>Computer Physics Communications, Vol. 69, No. 2-3. ( 1992), pp. 306-316.</i><br /><br />In this paper we present a rigorous method for finding the electric field in two-and-one-half and three dimensional electromagnetic plasma simulations without resorting to computationally expensive transforms. A finite grid interpretation of the divergence equation [backward difference]·J = -[varpi][rho]/[varpi]t is offered which allows the current density and thus new local electric and magnetic field strengths to be determined directly from knowledge of charge motion. Rigorous charge conservation for local electromagnetic field solvers John Villasenor Oscar Buneman doi:10.1016/0010-4655(92)90169-Y Computer Physics Communications, Vol. 69, No. 2-3. ( 1992), pp. 306-316. 2008-06-04T16:20:17-00:00 1992 Computer Physics Communications 69 2-3 306 316 algorithm charge conservation electromagnetic field gauss law simulation solver http://www.citeulike.org/user/michaelbussmann/article/2879114 <i>Plasma Science, 1995. IEEE Conference Record - Abstracts., 1995 IEEE International Conference on (1995), 244.</i><br /><br />Summary form only given, as follows. Non-charge conserving current collection algorithms for relativistic PIC plasma simulations can cause errors in Gauss' law. These errors arise from violations of the continuity equation, ∇·J=-δp/δt. Two techniques for removing these errors are examined and compared, the Marder correction, a method which corrects electric fields locally and primarily affects short wavelengths, and a divergence correction, which uses a Poisson solve to correct the electric fields so that Gauss' law is enforced. The effect of each method on the the spectrum of the error (short wavelengths vs. long) are examined. Computational efficiency and accuracy of the two techniques is compared. Particular cases of interest include corrections in electromagnetic relativistic beam simulations A spectral comparison of two methods of removing errors in Gauss' law in a 2-dimensional PIC plasma simulation P Mardahl J Verboncoeur CK Birdsall doi:10.1109/PLASMA.1995.533236 Plasma Science, 1995. IEEE Conference Record - Abstracts., 1995 IEEE International Conference on (1995), 244. 2008-06-10T10:55:18-00:00 1995 Plasma Science, 1995. IEEE Conference Record - Abstracts., 1995 IEEE International Conference on 244 2d algorithm charge conservation gauss particle-in-cell pic simulation spectral http://www.citeulike.org/user/michaelbussmann/article/2861764 <i>Computer Physics Communications, Vol. 70, No. 3. (July 1992), pp. 447-450.</i><br /><br />During the 20 years in which two-dimensional electromagnetic particle-in-cell codes have been intensive use, duscussion has continued as to how best to honor both the Ampere-Maxwell equation and Gauss' law in spite of compromises made in the collection of the density and current terms from the particle coordinates. Boris' popular and very effective method corrects the divergence of the electric field, but that requires solution of a Poisson's equation. Marder has recently popularized a partial correction that is very simple and fast, even with complex meshes. A new viewpoint on Marder's correction suggests improvements and new possibilities. In this note, I restate Marder's procedure and analyze a simple modification that improves it and clarifies its relation to Boris' divergence correction. Finally, I show that the improved Marder scheme gives the same results as an "incomplete Boris" correction in which the exact Poisson solve is replaced by a single accelerated point-Jacobi iteration. This observation suggests further improvements. On enforcing Gauss' law in electromagnetic particle-in-cell codes Bruce doi:10.1016/0010-4655(92)90105-8 Computer Physics Communications, Vol. 70, No. 3. (July 1992), pp. 447-450. 2008-06-04T16:03:32-00:00 1992 Computer Physics Communications 70 3 447 450 algorithm electromagnetic gauss law particle-in-cell pic simulation http://www.citeulike.org/user/michaelbussmann/article/2860508 <i>Journal of Computational Physics, Vol. 68, No. 1. (January 1987), pp. 48-55.</i><br /><br />An algorithm is presented which solves a modified set of Maxwell's equations, none of them elliptic, in an electromagnetic PIC type code. The algorithm prevents large violations of Gauss' law by diffusing away numerical errors arising from the particle-to-grid apportionment method. There are no restrictions on the manner in which charge and current densities are determined from the particle distribution. In particular, point particles and simple linear interpolation are used. A method for incorporating Gauss' law into electromagnetic PIC codes Barry Marder doi:10.1016/0021-9991(87)90043-X Journal of Computational Physics, Vol. 68, No. 1. (January 1987), pp. 48-55. 2008-06-04T08:23:25-00:00 1987 Journal of Computational Physics 68 1 48 55 algorithm gauss law particle-in-cell pic simulation http://www.citeulike.org/user/michaelbussmann/article/2861786 <i>Computer Physics Communications, Vol. 135, No. 2. (1 April 2001), pp. 144-153.</i><br /><br />The new method of local electric current density assignment in the Particle-in-Cell code in Cartesian geometry is presented. The method is valid for an arbitrary quasi-particle form-factor assuming that quasi-particle trajectory over time step is a straight line. The method allows one to implement the PIC code without solving Poisson equation. The presented formula for the current density associated with the motion of a single quasi-particle is the unique linear combination of form-factor differences in consistency with the discrete continuity equation. The computation scheme is demonstrated in 2D and 3D. Exact charge conservation scheme for Particle-in-Cell simulation with an arbitrary form-factor Esirkepov doi:10.1016/S0010-4655(00)00228-9 Computer Physics Communications, Vol. 135, No. 2. (1 April 2001), pp. 144-153. 2008-06-04T16:15:19-00:00 2001 Computer Physics Communications 135 2 144 153 algorithm charge conservation gauss law particle-in-cell pic simulation http://www.citeulike.org/user/jyuh/article/2451529 <i>Biometrics, Vol. 64, No. 1. (March 2008), pp. 96-105.</i> A Latent-Class Mixture Model for Incomplete Longitudinal Gaussian Data Beunckens Caroline Molenberghs Geert Verbeke Geert Mallinckrodt Craig doi:10.1111/j.1541-0420.2007.00837.x Biometrics, Vol. 64, No. 1. (March 2008), pp. 96-105. 2008-03-01T14:23:55-00:00 2008 Biometrics 0006-341X 64 1 96 105 Blackwell Publishing gauss latent longitudinal missing rct http://www.citeulike.org/user/jaeseung/article/1080832 <i>(29 Jan 2007)</i><br /><br />We demonstrate two NMR techniques for factorizing large numbers using the Gauss sum method. The first one is based on differential excitation of a single spin magnetization by a cascade of RF pulses. The second method is based on spatial averaging and selective refocusing of magnetization for Gauss sums corresponding to factors. All factors of 16637 and 52882363 are successfully obtained. Factorizing Numbers with the Gauss Sum Technique: NMR Implementations TS Mahesh Nageswaran Rajendran Xinhua Peng Dieter Suter (29 Jan 2007) 2007-01-31T20:51:11-00:00 2007 factoring gauss nmr sum http://www.citeulike.org/user/jaeseung/article/868266 <i>(22 Sep 2006)</i><br /><br />We factor the number 157573 using an NMR implementation of Gauss sums. NMR experiment factors numbers with Gauss sums Michael Mehring Klaus Mueller Ilya Wolfgang Merkel Wolfgang Schleich (22 Sep 2006) 2006-09-25T18:15:04-00:00 2006 factoring gauss nmr sum http://www.citeulike.org/group/48/article/21224 <i>Nonlinearity, Vol. 18, No. 2., 505.</i> A generalization of the Gauss map and some classical theorems on continued fractions Simone Cruz LFCd Luiz doi:10.1088/0951-7715/18/2/003 Nonlinearity, Vol. 18, No. 2., 505. 2004-12-28T16:18:23-00:00 Nonlinearity 0951-7715 18 2 505 Institute of Physics Publishing classical continued fractions gauss map theorems http://www.citeulike.org/user/ansobol/article/882460 <i>(1 Oct 2006)</i><br /><br />For a finite Borel measure on Euclidean d-space, we show that Renyi dimension of index q can be computed using the L-q norms of the convolutions of the measure against Gaussian functions of different scales. Here we assume the index q is positive and not one. We give an example of a measure for which the upper Renyi dimension cannot be calculated using the least squares best fits to the log-log plot of the index-q partition function over the scale epsilon. We show that the usual partition function is of O-regular variation. This makes it possible to prove that for some calculations related to Renyi dimension, it suffices to consider certain discrete series of values for epsilon. Renyi Dimension and Gaussian Filtering Terry Loring (1 Oct 2006) 2006-10-03T08:25:56-00:00 2006 fractal gauss renyi http://www.citeulike.org/user/akriesch/article/2983346 <i>J. Opt. Soc. Am. A, Vol. 14, No. 3. (1 March 1997), pp. 640-652.</i><br /><br />I expand the radiation potential of an arbitrary monochromatic electromagnetic wave in the cylindrical coordinate eigenfunctions of the scalar Helmholtz equation. Since the resulting beam shape coefficients are found to be an inverse Fourier transform of the z component of the beam fields, the incident Gaussian beam is parameterized by a Fourier angular spectrum of plane waves. The beam’s partial-wave coefficients are then obtained, as well as the scattered fields produced by the interaction of the beam with an infinitely long homogeneous circular cylinder. The fields are evaluated analytically in the far zone by the method of stationary phase, and the physical interpretation of the results are discussed extensively. Scattering of a diagonally incident focused Gaussian beam by an infinitely long homogeneous circular cylinder James Lock J. Opt. Soc. Am. A, Vol. 14, No. 3. (1 March 1997), pp. 640-652. 2008-07-10T00:11:23-00:00 1997 J. Opt. Soc. Am. A 14 3 640 652 OSA cylinder gauss scattering theory thesis