3,925 research outputs found
Convex Ancient Solutions to Anisotropic Curve Shortening Flow
We construct a translating solution to anisotropic curve shortening flow and
show that for a given anisotropic factor , and a given
direction and speed, this translator is unique. We then construct an ancient
compact solution to anisotropic curve shortening flow, and show that this
solution, along with the appropriate translating solution, are the unique
solutions to anisotropic curve shortening flow that lie in a slab of a given
width and no smaller
National identity and social cohesion: theory and evidence for British social policy
Arguments that a national identity could create a sense of social unity, solidarity and cohesion in a national group have a long tradition in social and political theory. J. S. Mill, for instance, argued that âthe boundaries of governments should coincide in the main with those of nationalitiesâ because a state with several nationalities is one in which members are âartificially tied togetherâ (2001, 288). In Britain in the 2000s these arguments resurfaced in public and political discourse through a distancing from multiculturalism, which was increasingly seen as divisive, and a new emphasis on national unity and social cohesion through the promotion of British identity. There is, however, a lack of empirical research in Britain on what the relationship between national identity and social cohesion might actually be, and the strength of the relationship as compared with other issues that might also be important for social cohesion. This mixed-methods thesis attempts to address the research gap both through analysis of the Citizenship Survey covering England and Wales, and through semi-structured interviews with respondents of Black-African and Black-Caribbean ethnicity in an area of London. I argue first that the type of national identity in question is of crucial importance; a distinction between constitutional patriotism, civic national identity, and ethnic national identity is helpful, and evidence suggests the latter form may in fact be detrimental to some aspects of social cohesion. Second, I argue that social cohesion might be better broken up into two separate concepts â one referring to a commitment to certain of the stateâs institutions (termed âinstitutional cohesionâ), and the other to associational types of behaviour (termed âassociational cohesionâ) â since the correlates of each of the two concepts are rather different and their separation would resolve many of the confusions in academic and public discussions of social cohesion. Third, I find evidence to suggest that British identity may be of more relevance for the associational type of cohesion than the institutional type, but overall both British and English identity are of marginal relevance for social cohesion as compared to education, deprivation, and perceptions of discrimination. This suggests that attempts to use British identity as a tool to create unity and cohesion in the context of increasing diversity may not work or even be counterproductive; issues of inequality and discrimination may be much more important to address. Fourth, I reflect on the extent to which issues of unity and cohesion at the level of the nation-state are still relevant in the context of identity politics on the one hand, and processes of globalisation on the other. I argue that nation-states, for the time being, remain important sites of redistribution and reference points for perceptions of equality; to the extent that these issues are important for social cohesion, nation-states are therefore important too
On target: a history of the 863d AAA-AW-BN in the Second World War
From the Foreword:
The writing of this book began shortly before V~E day. Together with what had been scribbled in the unit history journal and more carefully entered in the more ostentatious records, refreshing notes and photographs submitted by battery representatives were used in the telling and illustrating of this integrated story of the 863d AAA A W Bn.
In this presentation, it was impossible to obtain and relate personal anecdotes involving each man in the battalion. Whether or not you are mentioned specifically, it is our hope that you see yourself described, albeit anonymously, in the experiences and sentiments and moods common to all in this memorable adventure of the 863d.
We have tried to gather and utilize all suitable information brought to our attention to give a full, cohesive, readable story of the battalion and all its officers and men, its campaigns, its missions, its organizational experiences, its troublous days and gayer times- in a word, its life as a military organization from date of activation on 1 June 1943 at Fort Totten, Long Island to V-J Day, 14 August 1945, in and around Bad Soden, Germany.
Sgt. Benjamin Gise, Editor-in-Chiefhttps://digicom.bpl.lib.me.us/ww_reg_his/1111/thumbnail.jp
Active In-Flight Load Redistribution Utilizing Fiber-Optic Shape Sensing and Multiple Control Surfaces
Morphing wing technologies have gained research interest in recent years as technological advancements pave the way for such innovations. A key benefit of such a morphing wing concept is the ability of the wing to transition into an optimal configuration at multiple flight conditions. Such a morphing wing will have applications not only in drag reduction but also in flutter suppression and gust alleviation. By manipulating the wing geometry to match a given flight profile it is likely that the wing will yield increases in not just aerodynamic efficiency but also structural efficiency. These structurally efficient designs will likely rely on some type of structural sensing system which will ensure the wing maintains positive margins throughout its flight profile
Solar Cell Panel and the Method for Manufacturing the Same
According to an aspect of an embodiment of the present disclosure, there is provided a solar cell panel and a method for manufacturing the same. The solar cell panel comprises: a solar cell for generating electric power from sunlight; a coverglass for covering the solar cell; transparent shims, which are disposed between the solar cell and the coverglass at the points where the distance between the solar cell and the coverglass needs to be controlled, and form a space between the solar cell and the coverglass; and adhesive layer, which fills the space between the solar cell and the coverglass and has the thickness the same as that of the transparent shims
A Simple Likelihood Method for Quasar Target Selection
We present a new method for quasar target selection using photometric fluxes
and a Bayesian probabilistic approach. For our purposes we target quasars using
Sloan Digital Sky Survey (SDSS) photometry to a magnitude limit of g=22. The
efficiency and completeness of this technique is measured using the Baryon
Oscillation Spectroscopic Survey (BOSS) data, taken in 2010. This technique was
used for the uniformly selected (CORE) sample of targets in BOSS year one
spectroscopy to be realized in the 9th SDSS data release. When targeting at a
density of 40 objects per sq-deg (the BOSS quasar targeting density) the
efficiency of this technique in recovering z>2.2 quasars is 40%. The
completeness compared to all quasars identified in BOSS data is 65%. This paper
also describes possible extensions and improvements for this techniqueComment: Updated to accepted version for publication in the Astrophysical
Journal. 10 pages, 10 figures, 3 table
Photometric redshifts and quasar probabilities from a single, data-driven generative model
We describe a technique for simultaneously classifying and estimating the
redshift of quasars. It can separate quasars from stars in arbitrary redshift
ranges, estimate full posterior distribution functions for the redshift, and
naturally incorporate flux uncertainties, missing data, and multi-wavelength
photometry. We build models of quasars in flux-redshift space by applying the
extreme deconvolution technique to estimate the underlying density. By
integrating this density over redshift one can obtain quasar flux-densities in
different redshift ranges. This approach allows for efficient, consistent, and
fast classification and photometric redshift estimation. This is achieved by
combining the speed obtained by choosing simple analytical forms as the basis
of our density model with the flexibility of non-parametric models through the
use of many simple components with many parameters. We show that this technique
is competitive with the best photometric quasar classification
techniques---which are limited to fixed, broad redshift ranges and high
signal-to-noise ratio data---and with the best photometric redshift techniques
when applied to broadband optical data. We demonstrate that the inclusion of UV
and NIR data significantly improves photometric quasar--star separation and
essentially resolves all of the redshift degeneracies for quasars inherent to
the ugriz filter system, even when included data have a low signal-to-noise
ratio. For quasars spectroscopically confirmed by the SDSS 84 and 97 percent of
the objects with GALEX UV and UKIDSS NIR data have photometric redshifts within
0.1 and 0.3, respectively, of the spectroscopic redshift; this amounts to about
a factor of three improvement over ugriz-only photometric redshifts. Our code
to calculate quasar probabilities and redshift probability distributions is
publicly available
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The impact of the COVID-19 pandemic on cancer care.
The COVID-19 pandemic has disrupted the spectrum of cancer care, including delaying diagnoses and treatment and halting clinical trials. In response, healthcare systems are rapidly reorganizing cancer services to ensure that patients continue to receive essential care while minimizing exposure to SARS-CoV-2 infection
Think Outside the Color Box: Probabilistic Target Selection and the SDSS-XDQSO Quasar Targeting Catalog
We present the SDSS-XDQSO quasar targeting catalog for efficient flux-based
quasar target selection down to the faint limit of the Sloan Digital Sky Survey
(SDSS) catalog, even at medium redshifts (2.5 <~ z <~ 3) where the stellar
contamination is significant. We build models of the distributions of stars and
quasars in flux space down to the flux limit by applying the
extreme-deconvolution method to estimate the underlying density. We convolve
this density with the flux uncertainties when evaluating the probability that
an object is a quasar. This approach results in a targeting algorithm that is
more principled, more efficient, and faster than other similar methods. We
apply the algorithm to derive low-redshift (z < 2.2), medium-redshift (2.2 <= z
3.5) quasar probabilities for all 160,904,060
point sources with dereddened i-band magnitude between 17.75 and 22.45 mag in
the 14,555 deg^2 of imaging from SDSS Data Release 8. The catalog can be used
to define a uniformly selected and efficient low- or medium-redshift quasar
survey, such as that needed for the SDSS-III's Baryon Oscillation Spectroscopic
Survey project. We show that the XDQSO technique performs as well as the
current best photometric quasar-selection technique at low redshift, and
outperforms all other flux-based methods for selecting the medium-redshift
quasars of our primary interest. We make code to reproduce the XDQSO quasar
target selection publicly available
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