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Trachemys gaigeae
Number of Pages: 6Integrative BiologyGeological Science
Russian Cities in Transition: The Impact of Market Forces in the 1990s
This paper analyses Russian city growth during the command and transition eras. Our main focus is on understanding the extent to which market forces are replacing command forces, and the resulting changes in Russian city growth patterns. We examine net migration rates for a sample of 171 medium and large cities for the period 1960 through 2002. We conclude that while the declining net migration rate was reversed during the first half of the 1990s, restrictions continued to matter during the early years of transition in the sense that net migration rates were lower in the restricted than in the unrestricted cities. This pattern seemingly came to an end in the late 1990s.http://deepblue.lib.umich.edu/bitstream/2027.42/40083/3/wp697.pd
Inhomogeneous superconductivity and the "pseudogap state of novel superconductors
Novel superconducting compounds such as the high Tc oxides are intrinsically
inhomogeneous systems. An inhomogeneous structure is created by doping and the
statistical nature of the distribution of dopants. Consequently, the critical
temperature is spatially dependent: Tc = Tc (r).Comment: 63 pages text, 13 figures and 1 tabl
Russian Cities in Transition: The Impact of Market Forces in the 1990s
This paper analyses Russian city growth during the command and transition eras. Our main focus is on understanding the extent to which market forces are replacing command forces, and the resulting changes in Russian city growth patterns. We examine net migration rates for a sample of 171 medium and large cities for the period 1960 through 2002. We conclude that while the declining net migration rate was reversed during the first half of the 1990s, restrictions continued to matter during the early years of transition in the sense that net migration rates were lower in the restricted than in the unrestricted cities. This pattern seemingly came to an end in the late 1990s.cities; city growth; migration; Russia; urbanization
Accurate object reconstruction by statistical moments
Statistical moments can offer a powerful means for object description in object sequences. Moments used in this way provide a description of the changing shape of the object with time. Using these descriptions to predict temporal views of the object requires efficient and accurate reconstruction of the object from a limited set of moments, but accurate reconstruction from moments has as yet received only limited attention. We show how we can improve accuracy not only by consideration of formulation, but also by a new adaptive thresholding technique that removes one parameter needed in reconstruction. Both approaches are equally applicable for Legendre and other orthogonal moments to improve accuracy in reconstruction
Parameter estimation for macroscopic pedestrian dynamics models from microscopic data
In this paper we develop a framework for parameter estimation in macroscopic
pedestrian models using individual trajectories -- microscopic data. We
consider a unidirectional flow of pedestrians in a corridor and assume that the
velocity decreases with the average density according to the fundamental
diagram. Our model is formed from a coupling between a density dependent
stochastic differential equation and a nonlinear partial differential equation
for the density, and is hence of McKean--Vlasov type. We discuss
identifiability of the parameters appearing in the fundamental diagram from
trajectories of individuals, and we introduce optimization and Bayesian methods
to perform the identification. We analyze the performance of the developed
methodologies in various situations, such as for different in- and outflow
conditions, for varying numbers of individual trajectories and for differing
channel geometries
Principles and Implementation of Deductive Parsing
We present a system for generating parsers based directly on the metaphor of
parsing as deduction. Parsing algorithms can be represented directly as
deduction systems, and a single deduction engine can interpret such deduction
systems so as to implement the corresponding parser. The method generalizes
easily to parsers for augmented phrase structure formalisms, such as
definite-clause grammars and other logic grammar formalisms, and has been used
for rapid prototyping of parsing algorithms for a variety of formalisms
including variants of tree-adjoining grammars, categorial grammars, and
lexicalized context-free grammars.Comment: 69 pages, includes full Prolog cod
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