5,750 research outputs found
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Large-scale population movements into and from Britain south of Hadrian's Wall in the fourth to sixth centuries AD
The Dark Energy Survey
We describe the Dark Energy Survey (DES), a proposed optical-near infrared
survey of 5000 sq. deg of the South Galactic Cap to ~24th magnitude in SDSS
griz, that would use a new 3 sq. deg CCD camera to be mounted on the Blanco 4-m
telescope at Cerro Telolo Inter-American Observatory (CTIO). The survey data
will allow us to measure the dark energy and dark matter densities and the dark
energy equation of state through four independent methods: galaxy clusters,
weak gravitational lensing tomography, galaxy angular clustering, and supernova
distances. These methods are doubly complementary: they constrain different
combinations of cosmological model parameters and are subject to different
systematic errors. By deriving the four sets of measurements from the same data
set with a common analysis framework, we will obtain important cross checks of
the systematic errors and thereby make a substantial and robust advance in the
precision of dark energy measurements.Comment: White Paper submitted to the Dark Energy Task Force, 42 page
Distribution, Abundance, and Biological Characteristics of Groundfish off the Coast of Washington, Oregon, and California, 1977-1986
We compare results of bottom trawl surveys off Washington, Oregon, and California in 1977, 1980, 1983, and 1986 to discern trends in population abundance, distribution, and
biology. Catch per unit of effort, area-swept biomass estimates, and age and length compositions for 12 commercially important west coast groundfishes are presented to illustrate trends over the lO-year period. We discuss the precision, accuracy, and statistical significance of observed trends in abundance estimates. The influence of water temperature on the distribution of groundfishes is also briefly examined. Abundance estimates of canary rockfish, Sebastes pinniger, and yellowtail rockfish, S. Jlavidus, declined during the study
period; greater declines were observed in Pacific ocean perch, S. alutus, lingcod, Ophiodon elongatus, and arrowtooth flounder, Atheresthes stomias. Biomass estimates of Pacific hake, Merluccius productus, and English, rex, and Dover soles (Pleuronectes vetulus, Errex zachirus,
and Microstomus pacificus) increased, while bocaccio, S. paucispinis, and chilipepper, S. goodei, were stable. Sablefish, Anoplopoma fimbria, biomass estimates increased markedly from 1977 to 1980 and declined moderately thereafter. Precision was lowest for rockfishes, lingcod, and sablefish; it was highest for flatfishes because they were uniformly distributed. The accuracy of survey estimates could be gauged only for yellowtail and canary rockfish and sablefish. All fishery-based analyses produced much larger estimates of abundance than bottom trawl surveys-indicative of the true catchability of survey trawls. Population trends from all analyses compared well except in canary rockfish, the species that presents the
greatest challenge to obtaining reasonable precision and one that casts doubts on the usefulness of bottom trawl surveys for estimating its abundance. (PDF file contains 78 pages.
Fast Sketch-based Recovery of Correlation Outliers
Many data sources can be interpreted as time-series, and a key problem is to identify which pairs out of a large collection of signals are highly correlated. We expect that there will be few, large, interesting correlations, while most signal pairs do not have any strong correlation. We abstract this as the problem of identifying the highly correlated pairs in a collection of n mostly pairwise uncorrelated random variables, where observations of the variables arrives as a stream. Dimensionality reduction can remove dependence on the number of observations, but further techniques are required to tame the quadratic (in n) cost of a search through all possible pairs.
We develop a new algorithm for rapidly finding large correlations based on sketch techniques with an added twist: we quickly generate sketches of random combinations of signals, and use these in concert with ideas from coding theory to decode the identity of correlated pairs. We prove correctness and compare performance and effectiveness with the best LSH (locality sensitive hashing) based approach
Crossing the Pale: Representations of White Western Women in Indian Film and Media
In this paper I focus on the way the white Western woman is scripted into two recent Indian films, and show how colonial discourses still affect the way she is represented today in Indian media. More than just a simple plot device, her usevalue in partnership or sexual relations to the Indian male protagonist, rests upon two points: one, the power she represents due to her position as a signifier of Western economic forces, two, her projection as seductress and victim in colonialist discourses that characterised the Indian male as effeminate and rapacious of English women. The films I will discuss are: Lagaan: Once Upon a Time in India (Dir.Ashutosh Gowariker, 2001) and Rang de Basanti: A Generation Awakens (Dir.Rakeysh Omprakesh Mehra, 2006). I will also look at an advertisement for an Indian clothing company
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A famous Arthur in the sixth century? Reconsidering the origins of the Arthurian legend
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Constructing Melchior Lorichs's 'Panorama of Constantinople'
In Constructing Melchior Lorichs's Panorama of Constantinople, Nigel Westbrook, Kenneth Rainsbury Dark, and Rene Van Meeuwen propose that Melchior Lorichs's 1559 Panorama of Constantinople was created by using a viewing grid. The panorama is thus a reliable graphic source for the lost or since-altered Ottoman and Byzantine buildings of the city. The panorama appears to lie outside the conventional symbolic mode of topographical depiction common for its period and constitutes a rare "scientific" record of an encounter of a perspicacious observer with a vast subject. The drawing combines elements of allegory with extensive empirical observation. Several unknown structures, shown on the drawing, have been located in relation to the present-day topography of Istanbul, as a test-case for further research
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