1,387 research outputs found
The GOAL-to-HAL/S translator specification
The specification sets forth a technical framework within which to deal with the transfer of specific GOAL features to HAL/S. Key technical features of the translator are described which communicate with the data bank, handle repeat statements, and deal with software interrupts. GOAL programs, databank information, and GOAL system subroutines are integrated into one GOAL in HAL/S. This output is fully compatible HAL/S source ready for insertion into the HAL/S compiler. The Translator uses a PASS1 to establish all the global data needed for the HAL/S output program. Individual GOAL statements are translated in PASS2. The specification document makes extensive use of flowcharts to specify exactly how each variation of each GOAL statement is to be translated. The specification also deals with definitions and assumptions, executive support structure and implementation. An appendix, entitled GOAL-to-HAL Mapping, provides examples of translated GOAL statements
Participation\u27s Effect on Organizational Readiness for Change: An Empirical Study
Organizational change management is a principal issue in virtually every organization. This cross sectional correlation study examined an array of variables (i.e., process, personality, and context -specific) that influence organizational readiness for change. Participation (process variable) was related to higher mean scores in each of the four distinct readiness for change scales and explained a significant amount of incremental variance in appropriateness, valence, and efficacy
History of Middle Ear Involvement and Speech/Language Development in Late Talkers
Late-talking and normally speaking toddlers with and without histories of middle ear involvement were followed for 2 years to assess speech and expressive language outcomes. Results revealed no differences in expressive language outcome that could be attributed to history of middle ear involvement in either group. There did seem to be differences in outcome on measures of articulation that were associated with history of middle ear involvement. The implications of these findings for treatment of otitis media and for referral of late-talking toddlers for speech and language services are discussed
Beyond non-backtracking:Non-cycling network centrality measures
Walks around a graph are studied in a wide range of fields, from graph theory and stochastic analysis to theoretical computer science and physics. In many cases it is of interest to focus on non-backtracking walks; those that do not immediately revisit their previous location. In the network science context,imposing a non-backtracking constraint on traditional walk-based node centrality measures is known to offer tangible benefits. Here, we use the Hashimoto matrix construction to characterize, generalize and study such non-backtracking centrality measures. We then devise a recursive extension that systematically removes triangles, squares and, generally, all cycles up to a given length. By characterizing the spectral radius of appropriate matrix power series, we explore how the universality results on the limiting behaviour of classical walk-based centrality measures extend to these non-cycling cases. We also demonstrate that the new recursive construction gives rise to practical centrality measures that can be applied to large scale networks
Photon deflection and precession of the periastron in terms of spatial gravitational fields
We show that a Maxwell-like system of equations for spatial gravitational
fields and (latter being the analogy of a magnetic field),
modified to include an extra term for the field in the expression for
force, leads to the correct values for the photon deflection angle and for the
precession of the periastron
Limited refugia and high velocity range-shifts predicted for bat communities in drought-risk areas of the Northern Hemisphere
Abstract Species occupying semi-arid and dry regions around the globe face an uncertain future due to increases in the frequency and severity of droughts. In this study we modelled the potential effect of climate change on bat communities within two high-drought risk regions of the world and assessed the magnitude and direction of the predicted shifts in climatic suitability, locating climate change refugia and identifying species at greatest risk of population declines. To do this, we compared climate suitability models for 43 species using three global climate models and three emissions scenarios for current (1950–2000) and future (2061–2080) climates within two regions where droughts are predicted to increase, the Western Palaearctic and Western North America. Our models predicted an overall reduction in bat richness with future climates. Areas projected to support high species richness in the current climate coincided with greatest predicted species loss and greatest future drought risk. For species with the potential to extend their range, high velocity range shifts would be required to keep pace with these changes, particularly in the Western Palaearctic, where additional barriers to movement include seas and areas of high human population density. Predicted refugial zones were limited and occurred in similar areas across continents (montane and high latitude with some coastal areas). The area of climate suitability was predicted to contract for around half of study species, with nine identified as species of conservation concern due to low overlap between current and future modelled ranges. The best-case scenario for bat diversity in semi-arid and dry regions in the future is likely to be reduced species richness, with many species facing rapid range expansion over challenging landscapes to access climatically suitable areas. Conservation of bats in high drought risk regions will likely depend on protection of identified refugia and networks of water sources, as well as global measures to protect biodiversity and human wellbeing, such as reduction in global carbon emissions
On the shopfloor: exploring the impact of teacher trade unions on school-based industrial relations
Teachers are highly unionised workers and their trade unions exert an important influence on the shaping and implementation of educational policy. Despite this importance there is relatively little analysis of the impact of teacher trade unions in educational management literature. Very little empirical research has sought to establish the impact of teacher unions at school level. In an era of devolved management and quasi-markets this omission is significant. New personnel issues continue to emerge at school level and this may well generate increased trade union activity at the workplace. This article explores the extent to which devolved management is drawing school-based union representation into a more prominent role. It argues that whilst there can be significant differences between individual schools, increased school autonomy is raising the profile of trade union activity in the workplace, and this needs to be better reflected in educational management research
Electrodynamics with Lorentz-violating operators of arbitrary dimension
The behavior of photons in the presence of Lorentz and CPT violation is
studied. Allowing for operators of arbitrary mass dimension, we classify all
gauge-invariant Lorentz- and CPT-violating terms in the quadratic Lagrange
density associated with the effective photon propagator. The covariant
dispersion relation is obtained, and conditions for birefringence are
discussed. We provide a complete characterization of the coefficients for
Lorentz violation for all mass dimensions via a decomposition using
spin-weighted spherical harmonics. The resulting nine independent sets of
spherical coefficients control birefringence, dispersion, and anisotropy. We
discuss the restriction of the general theory to various special models,
including among others the minimal Standard-Model Extension, the isotropic
limit, the case of vacuum propagation, the nonbirefringent limit, and the
vacuum-orthogonal model. The transformation of the spherical coefficients for
Lorentz violation between the laboratory frame and the standard Sun-centered
frame is provided. We apply the results to various astrophysical observations
and laboratory experiments. Astrophysical searches of relevance include studies
of birefringence and of dispersion. We use polarimetric and dispersive data
from gamma-ray bursts to set constraints on coefficients for Lorentz violation
involving operators of dimensions four through nine, and we describe the mixing
of polarizations induced by Lorentz and CPT violation in the cosmic-microwave
background. Laboratory searches of interest include cavity experiments. We
present the theory for searches with cavities, derive the experiment-dependent
factors for coefficients in the vacuum-orthogonal model, and predict the
corresponding frequency shift for a circular-cylindrical cavity.Comment: 58 pages two-column REVTeX, accepted in Physical Review
Electrostatic boundary value problems in the Schwarzschild background
The electrostatic potential of any test charge distribution in Schwarzschild
space with boundary values is derived. We calculate the Green's function,
generalize the second Green's identity for p-forms and find the general
solution. Boundary value problems are solved. With a multipole expansion the
asymptotic property for the field of any charge distribution is derived. It is
shown that one produces a Reissner--Nordstrom black hole if one lowers a test
charge distribution slowly toward the horizon. The symmetry of the distribution
is not important. All the multipole moments fade away except the monopole. A
calculation of the gravitationally induced electrostatic self-force on a
pointlike test charge distribution held stationary outside the black hole is
presented.Comment: 18 pages, no figures, uses iopart.st
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