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Start Over Coverage 75-82

2. Interference difuzních elektronových vln v rovnovážných kovových nanovodičích

Creator:
Pospíšil, Jaroslav, Hrdý, Jan, and Pluháček, František
Format:
bez média and svazek
Type:
model:article and TEXT
Language:
Czech
Description:
The fundamental quantum-statistical and electromagnetical theoretical interpretation of the electrical conductance of diffuse free electrons in a nanometric metallic conductor under its thermodynamical, electrical and statistical equilibrium, regarding to an entrance and exit electron reservoir, is introduced in the present article. such a conductance is treated as the consequence of the quantummechanical phase coherence and interference of the adequate de broglie’s corpuscular (electron) waves in a metallic nanosample under the low absolute temperature. the formulae presented follow from application of the quantum Fermi-Dirac statistics of energetic distributions of free electrons in a metallic nanosample and from considerations about the two-beam interference of totally coherent electron waves over the entire nanosample, whose relative stochastic phase is controlled by an external tuning magnetic field. Furthermore, some contemporary methods of experimental verification of formulae mentioned above for a ring and straight metallic nanosample and homogeneous tuning magnetostatic field are then described and evaluated in the closing text of this article. and Článek uvádí fundamentální kvantově-statistickou a elektromagnetickou teoretickou interpretaci elektrické vodivosti difuzních volných elektronů v nanometrickém kovovém vodiči, který je v termodynamické a elektrické rovnováze se vstupním a výstupním elektronovým rezervoárem. Tato vodivost je pojímána jako důsledek kvantově-mechanické fázové koherence a interference příslušných de Broglieho částicových (elektronových) vln v kovovém nanovzorku o nízké absolutní teplotě. Prezentované vzorce vyplývají z aplikace kvantové Fermiho-Diracovy statistiky rozdělení energie volných elektronů v kovovém nanovzorku a z úvah o dvousvazkové interferenci v něm obsažených úplně koherentních elektronových vln, jejichž vzájemná náhodná fáze je říditelná ladicím vnějším magnetickým polem. Některé základní způsoby experimentálního ověření zmíněných vzorců pro prstencový a přímý kovový nanovzorek a ladicí homogenní magnetostatické pole jsou pak popsány a zhodnoceny v závěrečném textu tohoto článku.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Perspektivy korpusové lingvistiky: deskripce, nebo explanace?

Creator:
Štícha, František
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
description, explanation, corpus linguistics, empirical evidence, deskripce, explanace, korpusová lingvistika, and empirická evidence
Language:
Czech
Description:
This article engages in polemic with two papers on the status and prospects of corpus linguistics that were recently published by two Czech linguists in the journal Naše řeč (Our Language). These linguists claim that corpus linguistics relies too heavily on description, in general, and doesn’t provide sufficiently rigorous explanations. In contrast, the present author argues that working with large corpora (billions of tokens) does not necessarily lead to mere descriptions of language phenomena. Rather, descriptions based on large corpora facilitate rigorous explanations of grammatical phenomena. In addition, the author argues that until data-based descriptions became an integral part of work in the natural sciences, philosophically based explanations did not fully succeed at enabling us to understand the physical world. Language is a part of the natural world, and satisfactory grammatical explanations of natural languages require much more empirical evidence than could be obtained in the past without electronic corpora. Several examples of empirical evidence and their critical relevance to linguistic analysis are cited.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

4. Seasonal variation in the role of grey squirrels as hosts of Ixodes ricinus, the tick vector of the Lyme disease spirochaete, in a British woodland

Creator:
Craine, N.G., Randolph, S.E., and Nuttall, P.A.
Format:
print
Type:
model:internalpart and TEXT
Subject:
Ixodes ricinus, squirrels, mice, voles, pheasants, seasonality, and Borrelia burgdorferi
Language:
English
Description:
Data are presented on the variable patterns of the seasonal dynamics of Ixodes ricinus L. ticks seen questing on the vegetation and feeding on small rodents (mice and voles) and squirrels within a British woodland focus of Lyme borreliosis. Information on tick infestation levels on pheasants is also presented. The results show a prolonged, unimodal pattern of tick activity, with ticks feeding throughout the year in this sheltered habitat. If host density is taken into account, squirrels are quantitatively more important than small mammals as hosts for larval ticks from April until July, and overwhelmingly so for nymphal ticks throughout the year. The observed inter- and intraspecific differences in tick infestation levels are related to the behaviour of both hosts and ticks. Squirrels, as competent hosts for Borrelia burgdorferi and frequent occupants of habitats closely associated with man, will contribute significantly to the risk of Lyme disease.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. The impact of bridge pier on ice jam evolution - an experimental study

Creator:
Wang, Jun, Hua, Jian, Sui, Jueyi, Wu, Peng, Liu, Tao, and Chen, Pangpang
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
boundary condition, bridge pier, ice jam, and ice accumulation
Language:
Slovak
Description:
The ice jam in a river can significantly change the flow field in winter and early spring. The presence of bridge piers further complicates the hydraulic process by interacting between the ice jam and bridge piers. Using the data collected from experiments in a laboratory flume, the evolution of an ice jam around bridge piers having three different diameters has been investigated in this study. Compared to results without-pier, it was found that the formation of an ice jam in the downstream of bridge pier is faster than that in the upstream. The thickness distribution of the ice jam shows clearly different characteristics in front and behind of bridge piers at different stages of the ice jam.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public