Results 11 to 20 of about 1,869 (198)

Structure of the Galaxy [PDF]

open access: yesSymposium - International Astronomical Union, 1964
The title which the organizers of the Symposium have suggested for this introductory report covers an enormous domain. Even if one limits oneself, as I intend to do, to the large-scale structure, it is impossible to summarize this adequately in one communication.
openaire   +1 more source

Some Properties of Galaxy Structures [PDF]

open access: yesOpen Astronomy, 2011
Abstract We analysed some properties of galaxies structures based on the PF catalog of galaxy structures (Panko & Flin 2006) and the Tully NBG catalog (Tully 1988). At first, we analyzed the orientation of galaxies in the 247 optically selected rich Abell clusters, having at least 100 members. The distribution of the position angles
Flin Piotr   +4 more
openaire   +3 more sources

Spiral structure in external galaxies [PDF]

open access: yesSymposium - International Astronomical Union, 1970
The need for observing at least four different categories of optical objects for a satisfactory definition of optical spiral structure is emphasized. A sequence of optical form-types for the description of spiral structure is outlined. A pronounced difference in the nature of the spiral structure of the outer and inner parts of Messier 33 is ...
openaire   +1 more source

STRUCTURE AND FORMATION OF ELLIPTICAL AND SPHEROIDAL GALAXIES [PDF]

open access: yesThe Astrophysical Journal Supplement Series, 2009
New surface photometry of all known elliptical galaxies in the Virgo cluster is added to published data to derive composite profiles over large dynamic ranges. Sersic functions fit them remarkably well. Effective brightnesses and radii are derived via Sersic fits and by integrating the profiles nonparametrically. We strongly confirm two dichotomies: (1)
Kormendy, J.   +3 more
openaire   +3 more sources

Structure and Dynamics of Elliptical Galaxies

open access: yesAnnual Review of Astronomy and Astrophysics, 1991
The equilibrium models, observations and formation processes of elliptical galaxies are reviewed.
Zeeuw, P.T. de, Franx, M.
openaire   +3 more sources

FORMATION AND MAINTENANCE OF SPIRAL STRUCTURE IN GALAXIES [PDF]

open access: yesSymposium - International Astronomical Union, 1985
The formation and maintenance of spiral structure in galaxies is discussed in terms of spiral modes with a general perception consistent with the hypothesis of quasi-stationary spiral structure. The latter is explained in some detail to give it the original proper perspective and to contrast it with recent studies of non-stationary spiral structures ...
C. C. Lin, G. Bertin
openaire   +1 more source

The Theory of Spiral Structure of Galaxies [PDF]

open access: yesSymposium - International Astronomical Union, 1970
A Landau-type instability mechanism for generating spiral waves is suggested.Two populations of stars, Populations I and II, are considered, the second one with mean rotational velocity zero. Then a dispersion relation is derived which is reduced to the Lin-Shu dispersion relation in the case of vanishing Population II. The amplification of the wave is
openaire   +1 more source

Surrogate‐Optimized Flow‐Guided Miniature Condenser for Rapid Exhaled Glucose Detection

open access: yesAdvanced Materials Technologies, EarlyView.
A surrogate‐optimized miniature condenser guides humid exhaled flow toward cold surfaces to accelerate exhaled breath condensate collection. By improving vapor access within a compact footprint, the design increases sample yield. This enables post‐collection enrichment and rapid colorimetric glucose detection from dilute exhaled biomarkers within a 5 ...
Yiming Thomas Lu   +6 more
wiley   +1 more source

Continuum Robots in Surgery: From Engineering Design to Clinical Practice

open access: yesAdvanced Robotics Research, EarlyView.
The hyper‐redundant nature of continuum robot structures enables near‐infinite degrees of freedom leading to immense potential for medical applications. This review provides a historical background of continuum robots and novel ideas shaping their progress to current structural design, sensing technology, modeling techniques, and control methods.
Griffin Smith   +6 more
wiley   +1 more source

Structures in the universe and origin of galaxies [PDF]

open access: yesThe 33rd IEEE International Conference on Plasma Science, 2006. ICOPS 2006. IEEE Conference Record - Abstracts., 2006
15 pages, 17 figures, the part of materials of given paper has been represented in Conf. "New Vistas in Physics of Dusty Plasmas",and published in AIP Proc. of this Conference, editors: Laifa Boufendi, Vfxime Mikikian, P.K. Shukla, v. 799 (2005), pp.
openaire   +2 more sources

Home - About - Disclaimer - Privacy