Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 7

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  05.65.+b
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Self-Organization of Extreme Inequalities in a Competitive Society

100%
Odagaki T., Ishifuku A.
Acta Physica Polonica A
|
2018
|
vol. 133
|
issue 6
1459-1464
EN
On the basis of a random walk model, we investigate the self-organization of inequality in a model competitive society which consists of two kinds of individuals; one is warlike-challenging individuals who always try to fight and fight with the wealthiest or strongest neighbor, and the other is pacific-timid individuals who always try not to fight and when necessary fight with the poorest or weakest neighbor. When two individuals meet on a lattice site, they fight and the winner deprives a unit wealth from the loser keeping its position, where the winning odd is determined by a sigmoid function of the difference in their wealths. At the same time, the wealth or debt of individuals relaxes to zero at a constant rate when the wealth or debt is large. Using Monte Carlo simulation we determine states of social inequality in the entire parameter space spanned by the population density and the fraction of pacific-timid individuals in the population on the basis of the profile of the wealth distribution plotted against the ranking. We find an egalitarian state, and one normal inequal and three different extreme inequal states, the plutonomy, the gap inequality and the terrace inequality. In order to elucidate the origin of the self-organization, we investigate a model society consisting of individuals who have different moving strategies and no specific fighting strategy. It is concluded that the extreme inequalities are the consequence of the coexistence of different fighting strategies.
2
Content available remote

Identification of Insider Trading Using Network Numerical Models

80%
Jakimowicz A., Baklarz A.
Acta Physica Polonica A
|
2016
|
vol. 129
|
issue 5
980-985
EN
This article presents a network algorithm for identifying transactions which may constitute a violation of restricted periods, namely, making transactions in company shares by persons possessing inside information. The empirical research was performed on the basis of publicly available information on exchange trading, originating from the Warsaw Stock Exchange. The analysis is based on a numerical model which describes information spreading in a network with an information bottleneck. The applied method can confirm with high probability the use of inside information for carrying out unauthorized stock market transactions.
3
Content available remote

Intermittency and Deformation Band Propagation in an Austenitic FeMnC TWIP Steel

80%
Lebyodkin M., Lebedkina T., Roth A., Allain S.
Acta Physica Polonica A
|
2012
|
vol. 122
|
issue 3
478-481
EN
Plastic deformation of austenitic FeMnC TWIP steels exhibits complex spatiotemporal patterns associated with the occurrence of deformation bands and the concomitant fluctuations of the deforming stress. Although the plastic instability is a generic property of these steels and is usually attributed to interaction of dislocations with solutes (the Portevin-Le Chatelier effect), both the kinematics of the deformation bands and the characteristic shape of stress serrations observed in the carbon-containing TWIP steel at room temperature manifest unusual features. The nature of these peculiarities and the mechanism of jerky flow in such steels are unclear. In the present work, an attempt is made to get an insight into the jerky flow in the Fe22Mn0.6C steel by studying the time series characterizing the evolution of plastic deformation at various scales: stress-time curves, local strain field, and acoustic emission accompanying the deformation processes. Stress and strain fluctuations related to two distinct scale ranges are detected and characterized.
4
Content available remote

Acoustic-Emission Study of Intermittency of Plastic Flow during Twinning and Dislocation Glide

80%
Shashkov I., Lebedkina T., Lebyodkin M., Dobron P., Chmelik F., Kral R., Parfenenko K., Mathis K.
Acta Physica Polonica A
|
2012
|
vol. 122
|
issue 3
430-434
EN
Recent studies of plastic deformation with the aid of acoustic emission techniques proved an intermittent, scale-invariant character of plastic processes, as reflected in power-law statistical distributions. In some cases, the power-law exponents display close values leading to hypothesis of universality of scaling laws for various mechanisms of plasticity. Nevertheless, the accurate determination of the power law may be impeded by some sources of errors inevitable in real conditions, in particular, by superposition of individual acoustic emission events. In the present work, the sensitivity of the apparent statistics to the variation of the parameters of individualization of acoustic emission events is examined using Mg and Al based alloys. Both these alloys exhibit a highly cooperative character of plastic deformation, leading to strong acoustic activity which is governed by distinct microscopic mechanisms - mechanical twinning and the Portevin-Le Chatelier effect, respectively.
5
Content available remote

Self-Organization of Plutonomy in a Fair Competitive Society

80%
Todate Y., Fujie R., Odagaki T.
Acta Physica Polonica A
|
2016
|
vol. 129
|
issue 5
937-940
EN
We investigate the origin of the emergence of the plutonomy, an extreme form of hierarchy, where the top 1% of households account for more wealth than the bottom 99%. For a model fair society where individuals participate in a competition with equal right, we show that the plutonomy can be self-organized when individuals divided into several groups compete with those in the same group for a certain period (season) and they are regrouped at the end of every season. In the fair society, the wealth flows steadily from lower groups to the highest group, which is the origin of the plutonomy. Using mean-field analysis, we show that the fraction of winners decreases in proportion to the inverse of the number of groups.
6
Content available remote

Synthesis of Gold Nanoparticles Using Schiff Base

80%
Mihai S.
Acta Physica Polonica A
|
2013
|
vol. 123
|
issue 2
254-255
EN
The Schiff base is used for the first time in the preparation of gold nanoparticles by the interaction of tris (triphenylphosphinegold)oxonium tetrafloroborate in acetonitrile medium. The gold nanostructures were characterized using UV-vis spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The scanning electron microscopy allowed the examination of the morphology of the gold nanostructured film obtained by chemical deposition retains properties of individual particles and remain separated without undergoing aggregation.
7
Content available remote

A bicontinuous structure in some systems with cubic mesophases

51%
Yakunin A.
Open Physics
|
2004
|
vol. 2
|
issue 3
535-555
EN
A cubic structure of polymer colloid complexes is studied. The technique of the research includes i) an analysis of well-known literature SAXS data; on this basis, ii) constructing a simple model to estimate geometric structure parameters and to obtain a simulated scattering curve; and iii) comparing the model with the real structure obtained from the SAXS data, using the reconstruction of electron density distribution. A bicontinuous structure in cubic mesophases is formed.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.