161,613 research outputs found
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Skilful Coping with Unorder: Educating 21st Century Arts Leadership
This paper firstly addresses why innovative learning approaches are needed for 21st century leadership education in the arts and cultural sector, then moves on to a case study of how such approaches are being implemented in practice, in the Boosting Resilience project. The approaches taken here are characterised as involving a multi-disciplinary consortium of delivery partners; the use of constructivist pedagogy that draws on arts-based methods of delivery; a participatory and agile learning design process; and the incorporation of on-going evaluation activities, that are woven in to the process of design. The paper concludes with some discussion regarding the potential generalisability of approaches such as those employed on the Boosting Resilience project to arts and cultural leadership education more broadly
The K Band Luminosity Functions of Galaxies in High Redshift Clusters
K band luminosity functions (LFs) of three, massive, high redshift clusters
of galaxies are presented. The evolution of K*, the characteristic magnitude of
the LF, is consistent with purely passive evolution, and a redshift of forma
tion z = 1.5-2.Comment: 3 pages, to appear in Proceedings of IAU Colloquium 195 - Outskirts
of Galaxy Clusters: intense life in the suburb
On the Power-Law Tail in the Mass Function of Protostellar Condensations and Stars
We explore the idea that the power-law tail in the mass function of
protostellar condensations and stars arises from the accretion of ambient cloud
material on to a condensation, coupled with a nonuniform (exponential)
distribution of accretion lifetimes. This model allows for the generation of
power-law distributions in all star-forming regions, even if condensations
start with a lognormal mass distribution, as may be expected from the central
limit theorem, and supported by some recent numerical simulations of turbulent
molecular clouds. For a condensation mass with growth rate , an analytic three-parameter probability density function is derived; it
resembles a lognormal at low mass and has a pure power-law high-mass tail. An
approximate power-law tail is also expected for other growth laws, and we
calculate the distribution for the plausible case .
Furthermore, any single time snapshot of the masses of condensations that are
still accreting (and are of varying ages) also yields a distribution with a
power-law tail similar to that of the IMF.Comment: 5 pages, 4 figures, to appear in MNRAS (Letters section
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Citation and peer review of data: moving towards formal data publication
This paper discusses many of the issues associated with formally publishing data in academia, focusing primarily on the structures that need to be put in place for peer review and formal citation of datasets. Data publication is becoming increasingly important to the scientific community, as it will provide a mechanism for those who create data to receive academic credit for their work and will allow the conclusions arising from an analysis to be more readily verifiable, thus promoting transparency in the scientific process. Peer review of data will also provide a mechanism for ensuring the quality of datasets, and we provide suggestions on the types of activities one expects to see in the peer review of data. A simple taxonomy of data publication methodologies is presented and evaluated, and the paper concludes with a discussion of dataset granularity, transience and semantics, along with a recommended human-readable citation syntax
Regression with strongly correlated data
This paper discusses linear regression of strongly correlated data that
arises, for example, in magnetohydrodynamic equilibrium reconstructions. We
have proved that, generically, the covariance matrix of the estimated
regression parameters for fixed sample size goes to zero as the correlations
become unity. That is, in this limit the estimated parameters are known with
perfect accuracy. Simple examples are shown to illustrate this effect and the
nature of the exceptional cases in which the estimate covariance does not go to
zero
Geological evaluation and applications of ERTS-1 imagery over Georgia
ERTS-1 70mm and 9 x 9 film negatives are being used by conventional and color enhancement methods as a tool for geologic investigation. Geologic mapping and mineral exploration by conventional methods is very difficult in Georgia. Thick soil cover and heavy vegetation cause outcrops of bed rock to be small, rare and obscure. ERTS imagery, and remote sensing in general have helped delineate: (1) major tectonic boundaries; (2) lithologic contacts; (3) foliation trends; (4) topographic lineaments; and (5) faults. The ERTS-1 MSS imagery yields the greatest amount of geologic information on the Piedomont, Blue Ridge, and Valley and Ridge Provinces of Georgia where topography is strongly controlled by the bedrock geology. ERTS imagery, and general remote sensing techniques, have provided us with a powerful tool to assist geologic research; have significantly increased the mapping efficiency of our field geologists; have shown new lineaments associated with known shear and fault zones; have delineated new structural features; have provided a tool to re-evaluate our tectonic history; have helped to locate potential ground water sources and areas of aquifer recharge; have defined areas of geologic hazards; have shown areas of heavy siltation in major reservoirs; and by its close interval repetition, have aided in monitoring surface mine reclamation activities and the environmental protection of our intricate marshland system
Irrigation market for solar thermal parabolic dish systems
The potential size of the onfarm-pumped irrigation market for solar thermal parabolic dish systems in seven high-insolation states is estimated. The study is restricted to the displacement of three specific fuels: gasoline, diesel and natural gas. The model was developed to estimate the optimal number of parabolic dish modules per farm based on the minimum cost mix of conventional and solar thermal energy required to meet irrigation needs. The study concludes that the potential market size for onfarm-pumped irrigation applications ranges from 101,000 modules when a 14 percent real discount rate is assumed to 220,000 modules when the real discount rate drops to 8 percent. Arizona, Kansas, Nebraska, New Mexico and Texas account for 98 percent of the total demand for this application, with the natural gas replacement market accounting for the largest segment (71 percent) of the total market
c(2x2) Interface Alloys in Co/Cu Multilayers - Influence on Interlayer Exchange Coupling and GMR
The influence of a c(2x2) ordered interface alloy of 3d transition metals at
the ferromagnet/nonmagnet interface on interlayer exchange coupling (IXC), the
formation of quantum well states (QWS) and the phenomenon of Giant
MagnetoResistance is investigated. We obtained a strong dependence of IXC on
interface alloy formation. The GMR ratio is also strongly influenced. We found
that Fe, Ni and Cu alloys at the interface enhance the GMR ratio for in-plane
geometry by nearly a factor of 2.Comment: 14 pages, 5 figures, 1 table, subm. to PR
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