126,374 research outputs found
Design for orientation of balloon-borne equipment
Balloon-borne equipment consisting of gamma ray telescope with array of particle detector
Constraining coherent low frequency radio flares from compact binary mergers
The presence and detectability of coherent radio emission from compact binary
mergers (containing at least one neutron star) remains poorly constrained due
to large uncertainties in the models. These compact binary mergers may
initially be detected as Short Gamma-ray Bursts (SGRBs) or via their
gravitational wave emission. Several radio facilities have developed rapid
response modes enabling them to trigger on these events and search for this
emission. For this paper, we constrain this coherent radio emission using the
deepest available constraints for GRB 150424A, which were obtained via a
triggered observation with the Murchison Widefield Array. We then expand this
analysis to determine the properties of magnetar merger remnants that may be
formed via a general population of binary neutron star mergers. Our results
demonstrate that many of the potential coherent emission mechanisms that have
been proposed for such events can be detected or very tightly constrained by
the complementary strategies used by the current generation of low-frequency
radio telescopes.Comment: 19 pages, submitted to MNRA
Lithium/sulfur dioxide cell and battery safety
The new high-energy lithium/sulfur dioxide primary electrochemical cell, having a number of advantages, has received considerable attention as a power source in the past few years. With greater experience and improved design by the manufacturers, this system can be used in a safe manner provided the guidelines for use and safety precautions described herein are followed. In addition to a description of cell design and appropriate definitions, there is a safety precautions checklist provided to guide the user. Specific safety procedures for marking, handling, transportation, and disposal are also given, as is a suggested series of tests, to assure manufacturer conformance to requirements
Generalized valence bond wave functions in quantum Monte Carlo
We present a technique for using quantum Monte Carlo (QMC) to obtain high quality energy differences. We use generalized valence bond (GVB) wave functions, for an intuitive approach to capturing the important sources of static correlation, without needing to optimize the orbitals with QMC. Using our modifications to Walker branching and Jastrows, we can then reliably use diffusion quantum Monte Carlo to add in all the dynamic correlation. This simple approach is easily accurate to within a few tenths of a kcal/mol for a variety of problems, which we demonstrate for the adiabatic singlet-triplet splitting in methylene, the vertical and adiabatic singlet-triplet splitting in ethylene, 2+2 cycloaddition, and Be_2 bond breaking
Development of aircraft lavatory compartments with improved fire resistance characteristics. Phase 4: Sandwich panel decorative ink development
Five chemically different resin systems with improved fire resistance properties were studied for a possible screenprinting ink application. Fire resistance is hereby defined as the cured ink possessing improvements in flammability, smoke emission, and thermal stability. The developed ink is for application to polyvinyl fluoride film. Only clear inks without pigments were considered. Five formulations were evaluated compared with KC4900 clear acrylic ink, which was used as a baseline. The tests used in the screening evaluation included viscosity, smoke and toxic gas emission, limiting oxygen index (LOI), and polyvinyl fluoride film (PVF) printability. A chlorofluorocarbon resin (FPC461) was selected for optimization studies. The parameters for optimization included screenprinting process performance, quality of coating, and flammability of screenprinted 0.051-mm (0.002-in.) white Tedlar. The quality of the screenprinted coating on Tedlar is dependent on viscosity, curing time, adhesion to polyvinyl fluoride film, drying time (both inscreen and as an applied film), and silk screen mesh material and porosity
Unifying metastasis--Integrating intravasation, circulation and end organ colonization
Recent technological advances that have enabled the measurement of circulating tumour cells (CTCs) in patients have spurred interest in the circulatory phase of metastasis. Techniques that do not solely rely on a blood sample allow substantial biological interrogation beyond simply counting CTCs
A historical perspective on the Federal Reserve's monetary aggregates
Data on the monetary aggregates are the fundamental raw material for research in many facets of economics and finance. Money demand modeling, measurement of money stock announcement effects, tests of the rationality of preliminary money stock forecasts and financial market efficiency, and comparison of alternative seasonal adjustment procedures are just a few such areas. Working in the spirit of Friedman and Schwartz, we chronicle the evolution of the Federal Reserve's monetary aggregates. Numerous changes in data sources, definitions, revision procedures, and seasonal adjustment methods suggest caution for all researchers using monetary aggregate time series data. A timeline compiled by Kenneth Kavajecz shows each redefinition, revision and special event that affected the monetary aggregates from 1960-1993.Monetary policy - United States ; Money supply
A numerical study of forced lithospheric thinning
Subsolidus lithospheric thinning by mantle plumes may be involved in the creation of swells, hotspots, and rifts. Among the major questions concerning this process are the timescale on which it occurs and the structure of the plumes. The lithosphere is known to have been substantially thinned in 10 Ma or less. Current studies are focused on the lithospheric thinning by time-dependent plumes hypothesized to have large temperature differences across them
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Using infrared thermography for monitoring thermal efficiency of buildings - case studies from Nottingham Trent University
Global warming and the continuous increase of energy cost are driving the need for reducing energy consumption. Buildings are responsible for approximately 50% of the UK energy consumption. Major part of this consumption is for heating and air conditioning of buildings. Nottingham Trent University is a leading university in the UK in relation to improving the performance of its buildings in order to improve insulation and energy consumption. The experimental case studies presented in this paper highlights some of the new measures taken to reduce energy consumption and enhance the sustainability of the University buildings. Infrared thermography is used to evaluate insulation measures and energy performance. The results indicate that enhanced insulation combined with modern sustainable technologies can significantly reduce energy consumption
New Symbolic Tools for Differential Geometry, Gravitation, and Field Theory
DifferentialGeometry is a Maple software package which symbolically performs
fundamental operations of calculus on manifolds, differential geometry, tensor
calculus, Lie algebras, Lie groups, transformation groups, jet spaces, and the
variational calculus. These capabilities, combined with dramatic recent
improvements in symbolic approaches to solving algebraic and differential
equations, have allowed for development of powerful new tools for solving
research problems in gravitation and field theory. The purpose of this paper is
to describe some of these new tools and present some advanced applications
involving: Killing vector fields and isometry groups, Killing tensors and other
tensorial invariants, algebraic classification of curvature, and symmetry
reduction of field equations.Comment: 42 page
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