			Home About us Contact

Various Phenomena (various + phenomenon)

Distribution by Scientific Domains

Engineering	57%

Selected Abstracts

Investigation of nanoscale electrohydrodynamic transport phenomena in charged porous materials

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 14 2005
P. Pivonka
Abstract Depending on the permeability of porous materials, different mass transport mechanisms have to be distinguished. Whereas mass transport through porous media characterized by low permeabilities is governed by diffusion, mass transport through highly permeable materials is governed by advection. Additionally a large number of porous materials are characterized by the presence of surface charge which affects the permeability of the porous medium. Depending on the ion transport mechanism various phenomena such as co-ion exclusion, development of diffusion,exclusion potentials, and streaming potentials may be encountered. Whereas these various phenomena are commonly described by means of different transport models, a unified description of these phenomena can be made within the framework of electrohydrodynamics. In this paper the fundamental equations describing nanoscale multi-ion transport are given. These equations comprise the generalized Nernst,Planck equation, Gauss' theorem of electrostatics, and the Navier,Stokes equation. Various phenomena such as the development of exclusion potentials, diffusion,exclusion potentials, and streaming potentials are investigated by means of finite element analyses. Furthermore, the influence of the surface charge on permeability and ion transport are studied in detail for transient and steady-state problems. The nanoscale findings provide insight into events observed at larger scales in charged porous materials. Copyright © 2005 John Wiley Sons, Ltd. [source]

The Role of Political Instability in Stock Market Development and Economic Growth: The Case of Greece

ECONOMIC NOTES, Issue 3 2000
Dimitrios Asteriou
This article examines empirically the relationship between stock market development, political instability and economic growth in Greece. We measure socio-political instability by constructing an index which captures the occurrence of various phenomena of political violence using time-series data. The main advantages of analysing political instability in a case study framework using time-series, in contrast with the widely used cross-country empirical studies, are: (a) a more careful and in-depth examination of institutional and historical characteristics of a particular country; (b) the use of a data set comprised of the most appropriate and highest quality measures; and (c) a more detailed exposition of the dynamic evolution of the economy. The empirical results indicate the existence of a strong negative relationship between uncertain socio-political conditions and the general index of the Athens Stock Exchange (ASE) and support the theoretical hypothesis that uncertain socio-political conditions affect economic growth negatively, is true for the Greek case. (J.E.L.: G10, G14, O40, C32) [source]

Investigation of nanoscale electrohydrodynamic transport phenomena in charged porous materials

Tropospheric ducting phenomena over the Hellenic region

INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 4 2004
Stergios A. Isaakidis
Abstract The variation of the refractivity profiles of the troposphere and especially of the ducting effect, affects the radio wave propagation causing various phenomena such as refraction, fading and interference between radio-stations. In this work, the tropospheric ducting phenomena over the Hellenic region are studied using data from Helleniko and Thessaloniki Airports for the time period from 1991 to 1999. The data are analysed, corrected and enhanced using interpolation techniques and after a final statistical process the ducting conditions over the Hellenic region are summarized. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Law and Literature in the Romantic Era: The Law's Fictions

LITERATURE COMPASS (ELECTRONIC), Issue 4 2006
Sue Chaplin
This essay examines the emerging ideological relation between literature and law in the Romantic era and the significance of this relation to modern Western conceptualisations of what constitutes ,law' and ,literature'. In particular, the article explores the problematics of juridical textuality in the Romantic period , the extent to which the law comes to be regarded as text, and seeks to set this within the context of developing conceptualisations of ,literature' as a juridically defined commodity. The modern understanding of ,literature' began to be shaped in the Romantic era by a juridical re-formulation of the relation between the author, the text, the reader and the publisher: creative, original writing ,,literature', becomes a commodity copyrighted to an author/publisher. This development is accompanied by the State's recognition of the growing cultural and political power of new and diverse textual forms in an era of the mass production and consumption of ,literature', and the article considers alongside the contemporaneous formulation of copyright regulations the draconian censorship of textual production in this period. With reference to diverse juridical and literary sources (Clara Reeve's The Progress of Romance, Blackstone's Commentaries, Bentham's Fragment on Government, Godwin's Enquiry and Caleb Williams, amongst others), I examine the extent to which these various phenomena reveal the subjection of textuality in the Romantic era to the modern force of law. [source]

Accreting white dwarfs as supersoft X-ray sources

ASTRONOMISCHE NACHRICHTEN, Issue 2 2010
M. Kato
Abstract I review various phenomena associated with mass-accreting white dwarfs (WDs) in the view of supersoft X-ray sources. When the mass-accretion rate is low (,acc < a few × 10,7 M,yr,1), hydrogen nuclear burning is unstable and nova outbursts occur. A nova is a transient supersoft X-ray source (SSS) in its later phase which timescale depends strongly on the WD mass. The X-ray turn on/off time is a good indicator of the WD mass. At an intermediate mass-accretion rate an accreting WD becomes a persistent SSS with steady hydrogen burning. For a higher mass-accretion rate, the WD undergoes "accretion wind evolution" in which the WD accretes matter from the equatorial plane and loses mass by optically thick winds from the other directions. Two SSS, namely RX J0513-6951 and V Sge, are corresponding objects to this accretion wind evolution. We can specify mass increasing WDs from light-curve analysis based on the optically thick wind theory using multiwavelength observational data including optical, IR, and supersoft X-rays. Mass estimates of individual objects give important information for the binary evolution scenario of type Ia supernovae (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]