223 research outputs found
The ideological significance of flint in Dynastic Egypt
This thesis examines a little understood aspect of Dynastic Egypt—that of the ideology
of flint. Ideology is defined as the way flint is thought of rather than used. This study is
unique in examining long term chronological changes in flint ideology against the
background of increased metal use, and in using together text, iconography, and
archaeology: studies of Egyptian ideology traditionally privilege text.
Metaphor theory is employed as an important tool to aid this study. While
metaphor is frequently used in Egyptological studies of Egyptian religion, its use is
rarely explicit.
The dataset brings together unpublished artefacts in British museum
collections; a first hand analysis of lithics from Panhesy’s house at Amarna; finds
cards from recent excavations at Memphis; and textual sources, several of which have
not been considered before in relation to the ideology of flint; as well as published data
on Egyptian lithic material.
Chronological changes in ideology surrounding flint during the Bronze and
Iron Ages, a time of flint decline, are considered. Because the nature of flint decline in
Egypt has been assumed rather than known, I attempt to quantify the process.
Conclusions show that the ideology of flint was far from static but only loosely
related to the kinetic decline of flint. Flint is shown to be connected with the goddesses
who are the Eye of Re, with Re himself, with snakes and lions. New facets of flint
ideology are uncovered, including the connection of the material with the northern sky
and the link between the treatment of New Kingdom Theban flint concretions and the
religious landscape of the area
Recommended from our members
Integrated system for seismic evaluations
This paper describes the various features of the Seismic Module of the CARES system (Computer Analysis for Rapid Evaluation of Structures). This system was developed by Brookhaven National Laboratory (BNL) for the US Nuclear Regulatory Commission to perform rapid evaluations of structural behavior and capability of nuclear power plant facilities. The CARES is structured in a modular format. Each module performs a specific type of analysis i.e., static or dynamic, linear or nonlinear, etc. This paper describes the features of the Seismic Module in particular. The development of the Seismic Module of the CARES system is based on an approach which incorporates all major aspects of seismic analysis currently employed by the industry into an integrated system that allows for carrying out interactively computations of structural response to seismic motions. The code operates on a PC computer system and has multi-graphics capabilities. It has been designed with user friendly features and it allows for interactive manipulation of various analysis phases during the seismic design process. The capabilities of the seismic module include (a) generation of artificial time histories compatible with given design ground response spectra, (b) development of Power Spectral Density (PSD) functions associated with the seismic input, (c) deconvolution analysis using vertically propagating shear waves through a given soil profile, and (d) development of in-structure response spectra or corresponding PSD's. It should be pointed out that these types of analyses can also be performed individually by using available computer codes such as FLUSH, SAP, etc. The uniqueness of the CARES, however, lies on its ability to perform all required phases of the seismic analysis in an integrated manner. 5 refs., 6 figs
Octonion Quantum Chromodynamics
Starting with the usual definitions of octonions, an attempt has been made to
establish the relations between octonion basis elements and Gell-Mann \lambda
matrices of SU(3)symmetry on comparing the multiplication tables for Gell-Mann
\lambda matrices of SU(3)symmetry and octonion basis elements. Consequently,
the quantum chromo dynamics (QCD) has been reformulated and it is shown that
the theory of strong interactions could be explained better in terms of
non-associative octonion algebra. Further, the octonion automorphism group
SU(3) has been suitably handled with split basis of octonion algebra showing
that the SU(3)_{C}gauge theory of colored quarks carries two real gauge fields
which are responsible for the existence of two gauge potentials respectively
associated with electric charge and magnetic monopole and supports well the
idea that the colored quarks are dyons
At what scale should we assess the health of pelagic habitats? Trade-offs between small-scale manageable pressures and the need for regional upscaling
Publication history: Accepted - 26 June 2023; Published online - 13 July 2023.Major planktonic lifeforms such as diatoms, dinoflagellates, meroplankton and holoplankton have recently shown significant and alarming changes in abundance - mainly downwards trends - around the northwest European shelf. This has major implications for food web connections and for ecosystem services including seafood provision and carbon storage. We have quantified these changes in abundance for 2006–2019/20 using a Plankton Index (PI) and show that the scale of spatial aggregation is critical to the ability of the PI to detect change, understand causal mechanisms, and provide advice to policymakers. We derived PI statistics in the Celtic and North Seas from data from the Continuous Plankton Recorder survey offshore and England’s Environment Agency inshore using three sets of spatial units: (i) Ecohydrodynamic (EHD) units based on hydro-biogeochemical modelling, (ii) ‘COMP4′ areas based on cluster analysis of satellite data for chlorophyll a and primary productivity, and (iii) English coastal and estuarine Water Framework Directive (WFD) waterbodies. For the largest scale areas, the EHD units (median size 87,000 km2), we find greater change in plankton communities than previously reported, suggesting that these shifts have continued and possibly intensified in recent years. The smaller-scale COMP4 areas (median size 6,700 km2) appear to encompass more spatially coherent changes in plankton community structure than EHD units; at this scale PI values indicate community shifts of greater magnitude. These COMP4 areas provide a reasonable compromise scale for linking offshore plankton communities to large-scale drivers of change such as climate warming. For inshore plankton communities, larger changes are detected at the smaller WFD waterbody scale (median size 11 km2). This scale allows direct links to coastal management measures and is more suitable for linking to land-sourced pressures. Recent integration of the UK’s OSPAR and WFD plankton monitoring data management enables the exploration of changes across spatial scales to develop a holistic understanding of ecosystem health. Regional-sea scale derivation of the PI for coastal waters provides a clear indication that changes are occurring, at least in phytoplankton communities, while localised PI statistics offer an additional layer of information which can be an important tool for linking to localised drivers of change including coastal anthropogenic pressures. Broadscale inshore zooplankton monitoring is needed to evaluate the coastal plankton community holistically; zooplankton communities offshore are also changing but these changes cannot currently be linked to coastal processes. Layering information across spatial scales provides a breadth of system-level understanding beyond what any one typology can provide.This work was supported by the Defra/HBDSEG project ME414135 ‘DDIPA: Next-level pelagic habitat analysis: Making use of improved data flows to Delve Deeper into Integrated UK Plankton Assessment’, and Cefas’ Environment and People science theme. AA’s contribution was also funded by the UK Natural Environment Research Council (NERC) through its National Capability Long-term Single Centre Science Programme, Climate Linked Atlantic Sector Science, grant number NE/R015953/1, contributing to Theme 3.1—Biological dynamics in a changing Atlantic. EB and MM were additionally supported by the Scottish Government’s Schedule of Service ST02GH
Fitting the integrated Spectral Energy Distributions of Galaxies
Fitting the spectral energy distributions (SEDs) of galaxies is an almost
universally used technique that has matured significantly in the last decade.
Model predictions and fitting procedures have improved significantly over this
time, attempting to keep up with the vastly increased volume and quality of
available data. We review here the field of SED fitting, describing the
modelling of ultraviolet to infrared galaxy SEDs, the creation of
multiwavelength data sets, and the methods used to fit model SEDs to observed
galaxy data sets. We touch upon the achievements and challenges in the major
ingredients of SED fitting, with a special emphasis on describing the interplay
between the quality of the available data, the quality of the available models,
and the best fitting technique to use in order to obtain a realistic
measurement as well as realistic uncertainties. We conclude that SED fitting
can be used effectively to derive a range of physical properties of galaxies,
such as redshift, stellar masses, star formation rates, dust masses, and
metallicities, with care taken not to over-interpret the available data. Yet
there still exist many issues such as estimating the age of the oldest stars in
a galaxy, finer details ofdust properties and dust-star geometry, and the
influences of poorly understood, luminous stellar types and phases. The
challenge for the coming years will be to improve both the models and the
observational data sets to resolve these uncertainties. The present review will
be made available on an interactive, moderated web page (sedfitting.org), where
the community can access and change the text. The intention is to expand the
text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics &
Space Scienc
Scope for the Application of Mathematical Programming Techniques in the Synthesis and Planning of Sustainable Processes
Experiência de treinamento com Nintendo Wii sobre a funcionalidade, equilíbrio e qualidade de vida de idosas
Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET
The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR
On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection
A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)
- …