On Generalized Hexagons which Admit a Fundamental System of Root Automorphisms

1982 ◽  
Vol s3-45 (2) ◽  
pp. 281-299
Author(s):  
Michael Walker
Keyword(s):  
Fundamental System ◽  
Generalized Hexagons

Thin structure of heterogeneous and multiphase fluid flows

2012 ◽  
Vol 9 (1) ◽  
pp. 175-180
Author(s):  
Yu.D. Chashechkin
Keyword(s):  
Large Scale ◽  
Fundamental System ◽  
Fluid Flows ◽  
Regular Solutions ◽  
Flow Models ◽  
Group Methods ◽  
Wide Range ◽  
Thin Structure ◽  
Multiphase Fluid ◽  
Complete Solutions

According to the results of visualization of streams, the existence of structures in a wide range of scales is noted: from galactic to micron. The use of a fundamental system of equations is substantiated based on the results of comparing symmetries of various flow models with the usage of theoretical group methods. Complete solutions of the system are found by the methods of the singular perturbations theory with a condition of compatibility, which determines the characteristic equation. A comparison of complete solutions with experimental data shows that regular solutions characterize large-scale components of the flow, a rich family of singular solutions describes formation of the thin media structure. Examples of calculations and observations of stratified, rotating and multiphase media are given. The requirements for the technique of an adequate experiment are discussed.

scholarly journals CONFOR: A New Program for Determining the Connection Between Radio and Optical Reference Frames

1990 ◽  
Vol 141 ◽  
pp. 75-76
Author(s):  
V.S. Gubanov ◽  
I.I. Kumkova ◽  
V.V. Tel'Nyuk-Adamchuk
Keyword(s):  
Coordinate System ◽  
Reference Frames ◽  
Fundamental System ◽  
Optical Reference

The program for establishment of a link between the fundamental system FK5 and the radioastronomical coordinate system is described. The program includes photographic and meridian observations of extragalactic radio/optical sources and intermediate reference stars. Observatories of the USSR, GDR and Yugoslavia are participating in the project.

Variation in dinosaur skeletochronology indicators: implications for age assessment and physiology

Paleobiology ◽  
1999 ◽  
Vol 25 (3) ◽  
pp. 295-304 ◽  
Author(s):  
John R. Horner ◽  
Armand de Ricqlès ◽  
Kevin Padian
Keyword(s):  
Fundamental System ◽  
External Surface ◽  
Single Element ◽  
Age Assessment ◽  
Holotype Specimen ◽  
Physiological Evidence ◽  
Periosteal Surface ◽  
Single Bone

Twelve different bones from the skeleton of the holotype specimen of the hadrosaurian dinosaur Hypacrosaurus stebingeri were thin-sectioned to evaluate the significance of lines of arrested growth (LAGs) in age assessments. The presence of an external fundamental system (EFS) at the external surface of the cortex and mature epiphyses indicate that the Hypacrosaurus specimen had reached adulthood and growth had slowed considerably from earlier stages. The number of LAGs varied from none in the pedal phalanx to as many as eight in the tibia and femur. Most elements had experienced considerable Haversian reconstruction that had most likely obliterated many LAGs. The tibia was found to have experienced the least amount of reconstruction, but was still not optimal for skeletochronology because the LAGs were difficult to count near the periosteal surface. Additionally, the numbers of LAGs within the EFS vary considerably around the circumference of a single element and among elements. Counting LAGs from a single bone to assess skeletochronology appears to be unreliable, particularly when a fundamental system exists.Because LAGs are plesiomorphic for tetrapods, and because they are present in over a dozen orders of mammals, they have no particular physiological meaning that can be generalized to particular amniote groups without independent physiological evidence. Descriptions of dinosaur physiology as “intermediate” between the physiology of living reptiles and that of living birds and mammals may or may not be valid, but cannot be based reliably on the presence of LAGs.

Half-moufang generalized hexagons

2004 ◽  
Vol 141 (1) ◽  
pp. 83-92 ◽  
Author(s):  
Katrin Tent
Keyword(s):  
Generalized Hexagons

Two R-Closed Spaces

1972 ◽  
Vol 24 (2) ◽  
pp. 286-292 ◽  
Author(s):  
R. M. Stephenson
Keyword(s):  
Closed Subset ◽  
Fundamental System ◽  
Regular Space ◽  
Closed Space ◽  
Regular Topology ◽  
Regular Closed

Throughout this paper all hypothesized spaces are T1. A regular space is called R-closed[11](regular-closed [7] or, equivalently, regular-complete [2]) provided that it is a closed subset of any regular space in which it can be embedded. A regular space (X, ℐ) is called minimal regular [2; 4] if there exists no regular topology on X which is strictly weaker than J. We shall call a regular space X strongly minimal regular provided that each point x ∈ X has a fundamental system of neighbourhoods such that for every V ∈ , X\V is an R-closed space.In §2 we note that a strongly minimal regular space is minimal regular, but we do not know if the converse holds. M. P. Berri and R. H. Sorgenfrey [4] proved that a minimal regular space is R-closed, and Horst Herrlich [7] gave an example of an R-closed space that is not minimal regular.

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