Generation of Explicit Knowledge from Empirical Data through Pruning of Trainable Neural NetworksThis paper presents a generalized technology of extraction of explicit knowledge from data. The main ideas are 1) maximal reduction of network complexity (not only removal of neurons or synapses, but…A. N. Gorban, Eu. M. Mirkes, V. G. Tsaregorodtsev·Jul 3, 2003SaveLearn
On size and growth of business firmsWe study size and growth distributions of products and business firms in the context of a given industry. Firm size growth is analyzed in terms of two basic mechanisms, i.e. the increase of the…G. De Fabritiis, F. Pammolli, M. Riccaboni·Jul 3, 2003SaveLearn
Ising model with periodic pinning of mobile defectsA two-dimensional Ising model with short-range interactions and mobile defects describing the formation and thermal destruction of defect stripes is studied. In particular, the effect of a local…M. Holtschneider, W. Selke·Jul 3, 2003SaveLearn
Nanomechanical Analog of a Laser: Amplification of Mechanical Oscillations by Stimulated Zeeman TransitionsWe propose a magnetomechanical device that exhibits many properties of a laser. The device is formed by a nanocantilever and dynamically polarized paramagnetic nuclei of a solid sample in a strong…Igor Bargatin, M. L. Roukes·Jul 3, 2003SaveLearn
To detect the looped Bloch bands of Bose-Einstein condensates in optical latticesA loop structure was predicted to exist in the Bloch bands of Bose-Einstein condensates in optical lattices recently in [ Wu and Niu, Phys. Rev. A 61, 023402 (2000)]. We discuss how to…Dae-Il Choi, Biao Wu·Jul 2, 2003SaveLearn
Ferromagnetic phase transition and Bose-Einstein condensation in spinor Bose gasesPhase transitions in spinor Bose gases with ferromagnetic (FM) couplings are studied via mean-field theory. We show that an infinitesimal value of the coupling can induce a FM phase transition at a…Qiang Gu, Richard A. Klemm·Jul 2, 2003SaveLearn
A hybrid model for chaotic front dynamics: From semiconductors to water tanksWe present a general method for studying front propagation in nonlinear systems with a global constraint in the language of hybrid tank models. The method is illustrated in the case of semiconductor…A. Amann, K. Peters, U. Parlitz et al.·Jul 2, 2003SaveLearn
A Generalization of both the Method of Images and of the Classical Integral TransformsA new method for the solution of initial-boundary value problems for evolution PDEs recently introduced by Fokas is generalised to multidimensions. Also the relation of this method with the method of…Athanassios S. Fokas, Daniel ben-Avraham·Jul 1, 2003SaveLearn
Relaxation and Zeno effect in qubit measurementsWe consider a qubit interacting with its environment and continuously monitored by a detector represented by a point contact. Bloch-type equations describing the entire system of the qubit, the…S. A. Gurvitz, L. Fedichkin, D. Mozyrsky et al.·Jul 1, 2003SaveLearn
Simple Models of Plant Learning and MemoryPlants are capable of intelligent responses to complex environmental signals. Learning and memory play fundamental roles in such responses. Two simple models of plant memory are proposed based on the…Indrani Bose, Rajesh Karmakar·Jun 30, 2003SaveLearn
Phase separation in asymmetrical fermion superfluidsMotivated by recent developments on cold atom traps and high density QCD we consider fermionic systems composed of two particle species with different densities. We argue that a mixed phase composed…Paulo F. Bedaque, Heron Caldas, Gautam Rupak·Jun 27, 2003SaveLearn
BEC Collapse, Particle Production and Squeezing of the VacuumPhenomena associated with the controlled collapse of a Bose-Einstein condensate described in the experiment of Donley et al (E. Donley et. al., Nature 412, 295 (2001); N. Claussen, Ph. D. Thesis, U.…Esteban Calzetta, Bei Lok Hu·Jun 27, 2003SaveLearn
Low Temperature Properties of Finite Dimensional Ising Spin Glasses : (some) Numerical SimulationsWe review some recent results on finite dimensional spin glasses by studying recent numerical simulations and their relationship with experiments. In particular we will show results obtained at zero…J. J. Ruiz-Lorenzo·Jun 26, 2003SaveLearn
Scaling of the turbulence transition threshold in a pipeWe report the results of an experimental investigation of the transition to turbulence in a pipe over approximately an order of magnitude range in Re. A novel scaling law is uncovered using a…B. Hof, A. Juel, T. Mullin·Jun 26, 2003SaveLearn
Energetics and Possible Formation and Decay Mechanisms of Vortices in Helium NanodropletsThe energy and angular momentum of both straight and curved vortex states of a helium nanodroplet are examined as a function of droplet size. For droplets in the size range of many experiments, it is…Kevin K. Lehmann, Roman Schmied·Jun 26, 2003SaveLearn
Collision Drag Effect on Two-Fluid Hydrodynamics of Superfluid 3He in AerogelSound propagation in superfluid 3He in aerogel is studied on the basis of a two-fluid model taking into account the effect by the drag force due to collisions between 3He-quasiparticles and…M. Miura, S. Higashitani, M. Yamamoto et al.·Jun 25, 2003SaveLearn
Sum rules for free energy and frequency distribution of DNA dinucleotidesThe large discrepancy between the values of the free energy for DNA dinucleotides (or dimers) measured by different teams has raised a yet unsettled debate. Here the free energy is fitted by a three…L. Frappat, A. Sciarrino·Jun 25, 2003SaveLearn
Collective character of spin excitations in a system of Mn2+ spins coupled to a two-dimensional electron gasWe have studied the low energy spin excitations in n-type CdMnTe based dilute magnetic semiconductor quantum wells. For magnetic fields for which the energies for the excitation of free carriers and…F. J. Teran, M. Potemski, D. K. Maude et al.·Jun 25, 2003SaveLearn
Estimation of vortex density after superconducting film quenchThis paper addresses the problem of vortex formation during a rapid quench in a superconducting film. It builds on previous work showing that in a local gauge theory there are two distinct mechanisms…T. W. B. Kibble, A. Rajantie·Jun 25, 2003SaveLearn
Global Spread of Infectious DiseasesWe develop simple models for the global spread of infectious diseases, emphasizing human mobility via air travel and the variation of public health infrastructure from region to region. We derive…S. Hsu, A. Zee·Jun 25, 2003SaveLearn
Adiabatic Compression of Soliton Matter WavesThe evolution of atomic solitary waves in Bose-Einstein condensate (BEC) under adiabatic changes of the atomic scattering length is investigated. The variations of amplitude, width, and velocity of…F. Kh. Abdullaev, Mario Salerno·Jun 24, 2003SaveLearn
Surface Plasmons on a Quasiperiodic GratingA method is presented for calculating the frequencies of non-retarded surface plasmons propagating on a semi-inifinite medium with a surface profile described by a one-dimension quasiperiodic…J. Milton Pereira, G. A. Farias, R. N. Costa Filho·Jun 24, 2003SaveLearn
Transient growth of Kelvin waves on quantized vorticesQuantized vortex lines in helium II can be destabilized by a sufficiently large normal fluid velocity which is parallel to the vortex lines (Donnelly - Glaberson instability). We study what happens…C. F. Barenghi, M. Tsubota, A. Mitani et al.·Jun 24, 2003SaveLearn
Structure of boson systems beyond the mean-fieldWe investigate systems of identical bosons with the focus on two-body correlations. We use the hyperspherical adiabatic method and a decomposition of the wave function in two-body amplitudes. An…O. Sørensen, D. V. Fedorov, A. S. Jensen·Jun 23, 2003SaveLearn
Disorder effects at low temperatures in La0.7-xYxCa0.3MnO3 manganitesWith the aim of probing the effect of magnetic disorder in the low-temperature excitations of manganites, specific-heat measurements were performed in zero field, and in magnetic fields up to 9 T in…M. A. Gusmao, L. Ghivelder, R. S. Freitas et al.·Jun 23, 2003SaveLearn