Archaeology and art

Archaeologists have approached the study of art from several directions, drawing their inspiration variously from evolutionary biology, anthropology, and art history.We examine the strengths and weaknesses of each of these approaches and demonstrate the unique opportunities open to archaeology in the study of art, from its origins to the recent past

A Method for Determining Offtracking of Multiple Unit Vehicle Combinations

The required road width around curves on forest roads is largely determined by the difference in wheel paths between the inside front tractor wheel and the inside rear trailer wheel. This difference, known as offtracking, is a function of the vehicle and road geometry. This paper presents a method for determining the offtracking of fixed and variable length multiple unit vehicle combinations travelling over forest roads. The computational method numerically integrates the differential equations which compute the path (tractrix) that the rear of a vehicle follows from a given steering curve. A unique three-point solution method is used to determine the instantaneous center of rotation for trailers in the vehicle combination. The method is shown to have good agreement with experimental data. It is suitable for use on microcomputers for single and multiple curves. A microcomputer program, OFFTRACK, was developed using this methodology

Analytical Study of Certain Magnetohydrodynamic-alpha Models

In this paper we present an analytical study of a subgrid scale turbulence model of the three-dimensional magnetohydrodynamic (MHD) equations, inspired by the Navier-Stokes-alpha (also known as the viscous Camassa-Holm equations or the Lagrangian-averaged Navier-Stokes-alpha model). Specifically, we show the global well-posedness and regularity of solutions of a certain MHD-alpha model (which is a particular case of the Lagrangian averaged magnetohydrodynamic-alpha model without enhancing the dissipation for the magnetic field). We also introduce other subgrid scale turbulence models, inspired by the Leray-alpha and the modified Leray-alpha models of turbulence. Finally, we discuss the relation of the MHD-alpha model to the MHD equations by proving a convergence theorem, that is, as the length scale alpha tends to zero, a subsequence of solutions of the MHD-alpha equations converges to a certain solution (a Leray-Hopf solution) of the three-dimensional MHD equations.Comment: 26 pages, no figures, will appear in Journal of Math Physics; corrected typos, updated reference

Using movement, diet, and genetic analyses to understand Arctic charr responses to ecosystem change

ACKNOWLEDGEMENTS The extensive datasets used in this study were reliant on the dedication and innovation of many residents of Nunatsiavut (Food Skills and Environmental Research Program), technicians and biologists from DFO (J. Seiden, D. Lancaster, M. Shears, M. Bloom, S. Duffy), the Nunatsiavut Government (P. McCarney, C. Andersen, L. Pijogge), Oceans North (S. Pain), and of the captains and crew of the What’s Happening and the Safe Passage. Suggestions by three anonymous reviewers also greatly improved the manuscript. Funding for this research was provided in part by ArcticNet and DFO Oceans.Peer reviewedPublisher PD

Real-time lattice boltzmann shallow waters method for breaking wave simulations

We present a new approach for the simulation of surfacebased fluids based in a hybrid formulation of Lattice Boltzmann Method for Shallow Waters and particle systems. The modified LBM can handle arbitrary underlying terrain conditions and arbitrary fluid depth. It also introduces a novel method for tracking dry-wet regions and moving boundaries. Dynamic rigid bodies are also included in our simulations using a two-way coupling. Certain features of the simulation that the LBM can not handle because of its heightfield nature, as breaking waves, are detected and automatically turned into splash particles. Here we use a ballistic particle system, but our hybrid method can handle more complex systems as SPH. Both the LBM and particle systems are implemented in CUDA, although dynamic rigid bodies are simulated in CPU. We show the effectiveness of our method with various examples which achieve real-time on consumer-level hardware.Peer ReviewedPostprint (author's final draft

Time evolution, cyclic solutions and geometric phases for general spin in an arbitrarily varying magnetic field

A neutral particle with general spin and magnetic moment moving in an arbitrarily varying magnetic field is studied. The time evolution operator for the Schr\"odinger equation can be obtained if one can find a unit vector that satisfies the equation obeyed by the mean of the spin operator. There exist at least $2s+1$ cyclic solutions in any time interval. Some particular time interval may exist in which all solutions are cyclic. The nonadiabatic geometric phase for cyclic solutions generally contains extra terms in addition to the familiar one that is proportional to the solid angle subtended by the closed trace of the spin vector.Comment: revtex4, 8 pages, no figur

Accidental Releases of Sour Gas From Wells and Collection Pipelines in the Overthrust Belt: Calculating and Assessing Potential Health and Environmental Risks

Parts of the Overthrust Belt of western Wyoming and adjoining areas in Utah and Idaho contain geologic formations with significant accumulations of oil and natural gas. Some of these formations, though, yield gas that is contaminated with toxic hydrogen sulfide. As a consequence, the development of these so-called sour-gas reservoirs requires special safety procedures and technologies in order to prevent accidental releases of gas to the atmosphere that could cause adverse occupational and public health effects. To improve the analysis and assessment of wells and collection pipelines completed on lands leased from the Federal Government, the Minerals Management Service, Onshore Operations, now part of the Bureau of Land Management (BLM), asked Lawrence Livermore National Laboratory to conduct a study to test methods to the analysis of the potential risks associated with the development of sour-gas resources located near Evanston, Wyoming. The process of assessing the health risks of a potential sour-gas release involves estimation of the emission rate of hydrogen sulfide, specification of how the gas is released (e.g., vertically into the atmosphere or horizontally), prediction of downwind concentrations of the gas, analysis of the potential health effects, and finally, review of safety methods required to minimize the potential health risks. The first part of the report includes an analysis of data on the health effects of hydrogen sulfide to determine the nature of its dose-response relationship. Following that review is a study of the different methods of quantifying the emission rate of gas from wells and pipelines. Data on the frequency of accidental releases from those facilities are also analyzed. To assess the health risks of an accidental release from a well under BLM supervision located near Evanston, we collected meteorological data for 1 yr from four stations in that area. Our analysis of a worst-case release scenario (i.e., a gas plume that is near the surface) using those data indicates that the greatest risks of incurring an acute health effect (e.g., unconsciousness, respiratory arrest, pulmonary edema, or death) are located in the northwest sector downwind from the well because of the occurrence of stable atmospheric conditions along with slow winds from the southeast. The risks of an acute health effect in that northwest sector over the 20-yr operation of the well were on the order of 10 -4 to 10 -5 -- similar to the risk of accidental death caused by a natural disaster over the same period

Salford postgraduate annual research conference (SPARC) 2012 proceedings

These proceedings bring together a selection of papers from the 2012 Salford Postgraduate Annual Research Conference (SPARC). They reflect the breadth and diversity of research interests showcased at the conference, at which over 130 researchers from Salford, the North West and other UK universities presented their work. 21 papers are collated here from the humanities, arts, social sciences, health, engineering, environment and life sciences, built environment and business

The role of pathology in an investigation of an outbreak of West Nile encephalitis in New York, 1999.

An outbreak of encephalitis occurred in New York City in late August 1999, the first caused by West Nile virus in North America. Histopathologic and immunopathologic examinations performed on human autopsy materials helped guide subsequent laboratory and epidemiologic investigations that led to identification of the etiologic agent