854 research outputs found
Processing and Transmission of Information
Contains report on one research project.National Aeronautics and Space Administration (Grant NGL-22-009-013
Efficient optical communication in a turbulent atmosphere
Efficient optical communication in atmospheric turbulenc
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Many ways to Rome: Exogenous and endogenous pathways to environmental and social performance
It is often taken for granted that corporate social responsibility (CSR) will bring about social benefits and environmental improvements. Yet there is little empirical evidence of outcomes of CSR initiatives for the natural environment or the wider society as studies have focused on the influence of CSR on financial performance rather than its societal outcomes. This study begins addressing this gap in the literature by empirically studying the environmental and social performance of CSR in 19 European companies. We analyse which configurations of institutional constraints and organizational CSR practices influence environmental and social performance. Based on this analysis, we identify two pathways that can lead to high environmental and social performance and we scrutinize configurations that lead to low performance. The exogenous pathway is characterized by the use of externally certified management tools and certificates and a high importance of external rating schemes. This pathway seems typical for large publicly listed firms. The endogenous pathway, in turn, includes firms that are characterized by internally developed means of conducting CSR
Fully stable numerical calculations for finite onedimensional structures: mapping the Transfer Matrix method
We design a fully stable numerical solution of the Maxwell´s equations with the Transfer Matrix Method
(TMM) to understand the interaction between an electromagnetic field and a finite, one-dimensional, nonperiodic
structure. Such an exact solution can be tailored from a conventional solution by choosing an
adequate transformation between its reference systems, which induces a mapping between its associated
TMMs. The paper demonstrates theoretically the numerical stability of the TMM for the exact solution
within the framework of Maxwell´s equations, but the same formalism can efficiently be applied to
resolve other classical or quantum linear wave-propagation interaction in one, two, and three dimensions.
This is because the formalism is exclusively built up for an in depth analysis of the TMM´s symmetriesPeer reviewe
Value Efficiency Analysis for Incorporating Preference Information in Data Envelopment Analysis
We develop a procedure and the requisite theory for incorporating preference information in a novel way in the efficiency analysis of Decision Making Units. The efficiency of Decision Making Units is defined in the spirit of Data Envelopment Analysis (DEA), complemented with Decision Maker's preference information concerning the desirable structure of inputs and outputs. Our procedure begins by aiding the Decision Maker in searching for the most preferred combination of inputs and outputs of Decision Making Units (for short, Most Preferred Solution) which are efficient in DEA. Then, assuming that the Decision Maker's Most Preferred Solution maximizes his/her underlying (unknown) value function at the moment when the search is terminated, we approximate the indifference contour of the value function at this point with its possible tangent hyperplanes. Value Efficiency scores are then calculated for each Decision Making Unit comparing the inefficient units to units having the same value as the Most Preferred Solution. The resulting Value Efficiency scores are optimistic approximations of the true scores. The procedure and the resulting efficiency scores are immediately applicable to solving practical problems
Processing and Transmission of Information
Contains reports on three research projects.National Aeronautics and Space Administration (Grant NGL-22-009-013)Joint Services Electronics Programs (U.S. Army, U.S. Navy, and U.S. Air Force) under Contract DA 28-043-AMC-02536(E
Multitaxa species richness of a wood-pasture complex in the Finnish SW-archipelago
Traditional rural biotopes such as semi-natural grasslands and wood-pastures are among the most threatened biotopes in Finland. Archipelago Sea area hosts an especially representative collection of these biotopes, considering both their combined area and average quality. We surveyed birds, vascular plants, bryophytes, polypores and ground-inhabiting stipitate macrofungi in one wood-pasture complex in Korppoo, Archipelago Sea area. Here we report and discuss the results of these surveys. We detected altogether 457 species, including 8 red-listed bird species and 6 red-listed vascular plant species. We didn´t detect any red-listed bryophytes or fungi, but also these groups included several rare or indicator species as well as some fungal species not included in the latest Finnish red-list evaluation. The conservation value of this wood-pasture complex constitutes of species that are dependent on highly variable set of ecological conditions and habitats. This is related to highly variable conditions typical to wood pastures as a habitat
Symmetry analysis of the numerical instabilities in the transfer matrix method
This paper discusses the numerical exponential instability of the transfer matrix method (TMM) in the framework of the symmetry formalism. This numerical weakness is attributed to a series of increasingly extreme exponentials that appear in the TMM when it is applied to geometries involving total internal reflection (TIR) or very high absorption. We design a TMM formalism that identifies the internal symmetries of the multilayer geometry. These symmetries suggest particular transformations of a reference system in the TMM that improve its ill-conditioned exponentials. To illustrate the numerical improvements, we present examples with calculations of electric fields.Nordic Innovation Center 09053Ministerio de EconomĂa y Competitividad MAT2011-23593, CSD2007-00007Junta de AndalucĂa FQM- 3579, FQM-524
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