86 research outputs found
Decision Support System for Urbanization of the Northern Part of the Volga-Akhtuba Floodplain (Russia) on the Basis of Interdisciplinary Computer Modeling
There is a computer decision support system (CDSS) for urbanization of the
northern part of the Volga-Akhtuba floodplain. This system includes subsystems
of cognitive and game-theoretic analysis, geoinformation and hydrodynamic
simulations. The paper presents the cognitive graph, two-level and three-level
models of hierarchical games for the cases of uncontrolled and controlled
development of the problem situation. We described the quantitative analysis of
the effects of different strategies for the spatial distribution of the
urbanized territories. For this reason we conducted the territory zoning
according to the level of negative consequences of urbanization for various
agents. In addition, we found an analytical solution for games with the linear
dependence of the average flooded area on the urbanized area. We numerically
computed a game equilibrium for dependences derived from the imitational
geoinformation and hydrodynamic modeling of flooding. As the result, we showed
that the transition to the three-level management system and the implementation
of an optimal urbanization strategy minimize its negative consequences.Comment: 14 pages, 5 figures; Conference: Creativity in Intelligent
Technologies and Data Science. CIT&DS 201
The Shapes of Cooperatively Rearranging Regions in Glass Forming Liquids
The shapes of cooperatively rearranging regions in glassy liquids change from
being compact at low temperatures to fractal or ``stringy'' as the dynamical
crossover temperature from activated to collisional transport is approached
from below. We present a quantitative microscopic treatment of this change of
morphology within the framework of the random first order transition theory of
glasses. We predict a correlation of the ratio of the dynamical crossover
temperature to the laboratory glass transition temperature, and the heat
capacity discontinuity at the glass transition, Delta C_p. The predicted
correlation agrees with experimental results for the 21 materials compiled by
Novikov and Sokolov.Comment: 9 pages, 6 figure
Study on crystallization phenomenon and thermal stability of binary Ni–Nb amorphous alloy
In this paper, a ribbon of binary Ni–Nb amorphous
alloy was prepared by the melt spinning technique.
Glass transition and crystallization phenomenon of the
alloy were investigated by differential scanning calorimetry.
Thermal properties of the ribbon of binary Ni–Nb upon
heating and cooling were analysed by DTA at a heating/
cooling rate of 0.5 K s-1 under the purified argon
atmosphere. The thermal stability of Ni–Nb amorphous
alloy was studied by using an X-ray diffractometer
equipped with an in situ heating system. The structure and
fracture morphology of the ribbons were examined by
X-ray diffraction and scanning electron microscopy
methods
Varying constants, Gravitation and Cosmology
Fundamental constants are a cornerstone of our physical laws. Any constant
varying in space and/or time would reflect the existence of an almost massless
field that couples to matter. This will induce a violation of the universality
of free fall. It is thus of utmost importance for our understanding of gravity
and of the domain of validity of general relativity to test for their
constancy. We thus detail the relations between the constants, the tests of the
local position invariance and of the universality of free fall. We then review
the main experimental and observational constraints that have been obtained
from atomic clocks, the Oklo phenomenon, Solar system observations, meteorites
dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic
microwave background and big bang nucleosynthesis. At each step we describe the
basics of each system, its dependence with respect to the constants, the known
systematic effects and the most recent constraints that have been obtained. We
then describe the main theoretical frameworks in which the low-energy constants
may actually be varying and we focus on the unification mechanisms and the
relations between the variation of different constants. To finish, we discuss
the more speculative possibility of understanding their numerical values and
the apparent fine-tuning that they confront us with.Comment: 145 pages, 10 figures, Review for Living Reviews in Relativit
QCD and strongly coupled gauge theories : challenges and perspectives
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe
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