11,522 research outputs found
Dixmier traces and some applications to noncommutative geometry
This is a survey of some recent advances in the theory of singular traces in
which the authors have played some part and which were inspired by questions
raised by the book of Alain Connes (Noncommutative Geometry, Academic Press
1994). There are some original proofs and ideas but most of the results have
appeared elsewhere. Detailed information on the contents is contained in the
Introduction.Comment: To appear in Russian Mathematical Surveys (in Russian). New version
corrects Latex problems, minor errors and reference
The caloron correspondence and higher string classes for loop groups
We review the caloron correspondence between -bundles on
and -bundles on , where is the space of smooth loops in
the compact Lie group . We use the caloron correspondence to define
characteristic classes for -bundles, called string classes, by
transgression of characteristic classes of -bundles. These generalise the
string class of Killingback to higher dimensional cohomology.Comment: 21 pages. Author addresses adde
System Energy Assessment (SEA), Defining a Standard Measure of EROI for Energy Businesses as Whole Systems
A more objective method for measuring the energy needs of businesses, System
Energy Assessment (SEA), identifies the natural boundaries of businesses as
self-managing net-energy systems, of controlled and self-managing parts. The
method is demonstrated using a model Wind Farm case study, and applied to
defining a true physical measure of its energy productivity for society
(EROI-S), the global ratio of energy produced to energy cost. The traceable
needs of business technology are combined with assignable energy needs for all
other operating services. That serves to correct a large natural gap in energy
use information. Current methods count traceable energy receipts for technology
use. Self-managing services employed by businesses outsource their own energy
needs to operate, and leave no records to trace. Those uncounted energy demands
are often 80% of the total embodied energy of business end products. The scale
of this "dark energy" was discovered from differing global accounts, and
corrected so the average energy cost per dollar for businesses would equal the
world average energy use per dollar of GDP. Presently the energy needs of paid
services that outsource their own energy needs are counted for lack of
information to be "0". Our default assumption is to treat them as "average".
The result is to assign total energy use and impacts to the demand for energy
services, for a "Scope 4" GHG assessment level. Counting only the energy uses
of technology understates the energy needs of business services, as if services
were more energy efficient than technology. The result confirms a similar
finding by Hall et. al. in 1981 [9]. We use exhaustive search for what a
business needs to operate as a whole, locating a natural physical boundary for
its working parts, to define businesses as physical rather than statistical
subjects of science. :measurement, natural systemsComment: 33 pages, 15 figures, accepted as part of pending special issue on
EROI organized by Charlie Hall for Sustainability (MDPI
Credit risk rating at large U.S. banks
Large banks use internally developed credit rating systems to differentiate the riskiness of their commercial loans. Internal ratings are an essential ingredient of effective credit risk management for such banks, whose commercial borrowers may number in the tens of thousands. This article describes these rating systems, how their design varies across institutions, and how they are used in risk management. The article also outlines conceptual and practical difficulties currently faced by banks in achieving accurate and consistent ratings and describes ways in which some institutions have attempted to deal with these difficulties. This article is based on a detailed review of policy documents and internal management reports from the fifty largest U.S. bank holding companies and interviews by the authors at a selection of these institutions.Credit ratings ; Risk
Amino acids and amino sugars in calcified tissues of portunid crabs
Amino acid and amino sugar in calcified tissues of portunid crab
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