Author: Fritz Zwicky
Publisher: Springer Science & Business Media
ISBN: 3642875440
Category : Science
Languages : en
Pages : 304
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Book Description
Man has a great tendency to get lost or to hide, as the case may be, in a jungle of details and in unnecessary complications. Why do anything simply if you can do it complicated? And still, life itself presents a sufficient number of problems to keep us busy. There would seem to be no need to create additional difficulties, just for the fun of it, especially if these self-made difficulties become practically insuperable and if in the end they cause much unhappiness. The morphological mode of thought and of action was conceived to break the vicious hold which the parasitic wild growth of complications exerts on life in all of its phases. Morphological thought and action are likely to be of value in all human activities, once such thought and action have been clearly delineated and fully developed, and once they have been practised by a sufficiently large number of people. Since the morphological method is of the greatest universality, the choice of the field to which one applies it first is not particulary critical. The author intends to write two or three books on the morphology of several large scale problems, which are both of a technical and of a general social nature. The present book is concerned in particular with some implications of morphological thinking in astronomy. We shall above all emphasize the basic character of the morphological approach, and we shall demonstrate its constructive power in a number of specific cases.
Author: Fritz Zwicky
Publisher:
ISBN:
Category :
Languages : en
Pages : 23
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Book Description
Author: B. W. Holwerda
Publisher:
ISBN: 9780750334990
Category : Galaxies
Languages : en
Pages : 0
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Book Description
Galaxy morphology is a long-standing subfield of astronomy, moving from visual qualifications to quantitative morphometrics. This book covers the descriptions developed by astronomers to describe the appearance of galaxies, primarily in optical, ultraviolet and near-infrared wavelengths.
Author: Kieran Jay Edwards
Publisher: Springer Science & Business Media
ISBN: 3319065998
Category : Technology & Engineering
Languages : en
Pages : 112
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Book Description
With the onset of massive cosmological data collection through media such as the Sloan Digital Sky Survey (SDSS), galaxy classification has been accomplished for the most part with the help of citizen science communities like Galaxy Zoo. Seeking the wisdom of the crowd for such Big Data processing has proved extremely beneficial. However, an analysis of one of the Galaxy Zoo morphological classification data sets has shown that a significant majority of all classified galaxies are labelled as “Uncertain”. This book reports on how to use data mining, more specifically clustering, to identify galaxies that the public has shown some degree of uncertainty for as to whether they belong to one morphology type or another. The book shows the importance of transitions between different data mining techniques in an insightful workflow. It demonstrates that Clustering enables to identify discriminating features in the analysed data sets, adopting a novel feature selection algorithms called Incremental Feature Selection (IFS). The book shows the use of state-of-the-art classification techniques, Random Forests and Support Vector Machines to validate the acquired results. It is concluded that a vast majority of these galaxies are, in fact, of spiral morphology with a small subset potentially consisting of stars, elliptical galaxies or galaxies of other morphological variants.
Author: G. Longo
Publisher: Springer Science & Business Media
ISBN: 9401125228
Category : Science
Languages : en
Pages : 489
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Book Description
The morphological scheme devised by Hubble and followers to classify galaxies has proven over many decades to be quite effective in directing our quest for the fundamental pa rameters describing the extragalactic manifold. This statement is however far more true for spirals than for ellipticals. Echoing the concluding remarks in Scott Tremaine's sum mary talk at the Princeton meeting on Structure and Dynamics of Elliptical Galaxies, "the Hubble classification of spirals is useful because many properties of spirals (gas con tent, spiral arm morphology, bulge prominence, etc. ) all correlate with Hubble time. By contrast, almost nothing correlates with the elliptical Hubble sequence El to E7. " During the last few years much effort has been put into the search for a more meaningful classification of ellipticals than Hubble's. Concomitantly, forwarded by some provocative conjectures by R. Michard, the classical question of whether E galaxies form a physically homogeneous family has been brushed up once more. Results of these and other parallel studies look rather promising and point to suture part of the dichotomy between ellipticals and disk galaxies which had become popular in the early eighties, owing to dynamical arguments. At the same time it appears more and more clear that, besides the usual genetic varieties of galaxies, products of environmental evolution must also be contemplated in building our modern picture of the "reign of galaxies" . The above considerations prompted us to solicit Prof.
Author: Francesca Matteucci
Publisher: Springer Science & Business Media
ISBN: 3642224911
Category : Science
Languages : en
Pages : 237
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Book Description
The term “chemical evolution of galaxies” refers to the evolution of abundances of chemical species in galaxies, which is due to nuclear processes occurring in stars and to gas flows into and out of galaxies. This book deals with the chemical evolution of galaxies of all morphological types (ellipticals, spirals and irregulars) and stresses the importance of the star formation histories in determining the properties of stellar populations in different galaxies. The topic is approached in a didactical and logical manner via galaxy evolution models which are compared with observational results obtained in the last two decades: The reader is given an introduction to the concept of chemical abundances and learns about the main stellar populations in our Galaxy as well as about the classification of galaxy types and their main observables. In the core of the book, the construction and solution of chemical evolution models are discussed in detail, followed by descriptions and interpretations of observations of the chemical evolution of the Milky Way, spheroidal galaxies, irregular galaxies and of cosmic chemical evolution. The aim of this book is to provide an introduction to students as well as to amend our present ideas in research; the book also summarizes the efforts made by authors in the past several years in order to further future research in the field.
Author: Paolo Fornasiero
Publisher: Elsevier
ISBN: 0323446655
Category : Technology & Engineering
Languages : en
Pages : 712
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Book Description
Morphological, Compositional, and Shape Control of Materials for Catalysis, Volume 177, the latest in the Studies in Surface Science and Catalysis series, documents the fast-growing developments in the synthesis, characterization, and utilization of nanostructures for catalysis. The book provides essential background on using well-defined materials for catalysis and presents exciting new paradigms in the preparation and application of catalytic materials, with an emphasis on how structure determines catalytic properties. In addition, the book uniquely features discussions on the future of the field, with ample space for future directions detailed in each chapter. - Presents the latest paradigms in the preparation and application of catalytic materials - Provides essential background on using well-defined materials for catalysis - Features discussion of future directions at the end of each chapter
Author: Santiago Erroz-Ferrer
Publisher: Springer
ISBN: 3319263986
Category : Science
Languages : en
Pages : 207
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Book Description
This thesis discusses the evolution of galaxies through the study of the morphology, kinematics, and star formation properties of a sample of nearby galaxies. The main body of the thesis describes the kinematic observations with the GHaFAS Fabry-Perot instrument on the William Herschel Telescope of a sample of 29 spiral galaxies. The work is closely related to the Spitzer Survey of Stellar Structure in Galaxies, and uses the mid-infrared data of that survey to determine key parameters of the galaxies studied. From these data, important results are obtained on streaming and other non-circular motions in galaxies, on the distribution and rates of star formation, and on how correlations of these parameters and of the rotation curve shape with basic galaxy parameters yield clues on the evolutionary processes taking place in disk galaxies.
Author:
Publisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 496
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Book Description
Author: David L. Block
Publisher: Springer Science & Business Media
ISBN: 9401141142
Category : Science
Languages : en
Pages : 798
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Book Description
South Africa - a land of paradigm shifts. A land where we are willing to leave behind the old, to bravely accept the new. What do we need to exit the dark ages in the morphology of galaxies? How prevalent is the cherishing of old concepts? Traditional morphology has been `mask-oriented', focusing on masks of dust and gas which may constitute only 5 percent of the dynamical mass of a galaxy. Some of the world's foremost astronomers flew to South Africa to address morphologically related issues at an International Conference, the proceedings of which are contained in this volume. Examine predicted extinction curves for primordial dust at high redshift. Stars evolve; why not dust? Read about the breakdown of the Hubble sequence at a redshift of one. Explore the morphology of rings; the mysteries of metal-rich globular clusters; vigorous star-formation in the Large Magellanic Cloud; the world of secular evolution, where galaxies change their shapes within one Hubble time. And much more. Examine a new kinematical classification scheme of the unmasked, dust-penetrated near-infrared images of spiral galaxies. This volume contains over 80 refereed contributions (including 18 in-depth keynote review articles), 40 pages of questions and answers, a panel discussion transcribed from tape and 24 colour plates. The volume is unique in that contributions from both high and low redshift experts are represented at a level readily accessible to postdoctoral students entering the exciting world of morphology - whether it be of the local, or more distant, Universe.
