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Assessing the efficient cost of sustaining Britain's rail network: Perspectives based on zonal comparisons
The objective of this paper is to inform the debate on how efficiency targets for Network Rail (formerly Railtrack) should be set during the 2002/03 Interim Review and beyond. Given the problems experienced during the 2000 Periodic Review, which focused on external benchmarks, we propose an internal benchmarking approach, drawing on data for seven geographical Zones within Railtrack (over the period 1995/96 to 2001/02). Our approach mirrors the yardstick competition method used in other UK regulated industries. Three efficiency measurement techniques are applied to this data (DEA; COLS; SFA). Our results suggest that Railtrack (as a whole) delivered substantial improvements in productivity in the early years after privatisation, although these savings were largely offset by the post-Hatfield cost increases. However, looking forward, Zonal efficiency differences suggest that the company could make significant savings in future years by applying (its own) best practice consistently across the network
Historic preservation meets community development
For years, community development and historic preservation operated in their own worlds. Today a new awareness of common interests is enabling collaborations that produce benefits for all.Community development ; Historic preservation
Improving access to care in Virginia: Reaching nurse practitioner training capacity through preceptor incentives
Workforce data reinforces the notion that educating nurse practitioners in Virginia is critical in helping to improve access to care in the Commonwealth, particularly in underserved communities. Six of Virginia’s thirty-nine state funded colleges and universities offer nurse practitioner programs. All of these universities report their capacity to train nurse practitioners is not limited by qualified applicants but rather by a shortage of clinical preceptors. This paper provides a summary of public policy initiatives that support preceptors as an example for Virginia to consider
Tax credits for historic rehabilitation
Saving historic buildings preserves New England’s character while providing opportunities for affordable housing and economic development. The authors describe how to use federal historic tax credits as well as New England’s state-level historic tax credits.Tax credits - New England ; Historic preservation - New England ; Housing - New England
Emulation of multivariate simulators using thin-plate splines with application to atmospheric dispersion
It is often desirable to build a statistical emulator of a complex computer simulator in order to perform analysis which would otherwise be computationally infeasible. We propose methodology to model multivariate output from a computer simulator taking into account output structure in the responses. The utility of this approach is demonstrated by applying it to a chemical and biological hazard prediction model. Predicting the hazard area which results from an accidental or deliberate chemical or biological release is imperative in civil and military planning and also in emergency response. The hazard area resulting from such a release is highly structured in space and we therefore propose the use of a thin-plate spline to capture the spatial structure and fit a Gaussian process emulator to the coefficients of the resultant basis functions. We compare and contrast four different techniques for emulating multivariate output: dimension-reduction using (i) a fully Bayesian approach with a principal component basis, (ii) a fully Bayesian approach with a thin-plate spline basis, assuming that the basis coefficients are independent, and (iii) a “plug-in” Bayesian approach with a thin-plate spline basis and a separable covariance structure; and (iv) a functional data modeling approach using a tensor-product (separable) Gaussian process. We develop methodology for the two thin-plate spline emulators and demonstrate that these emulators significantly outperform the principal component emulator. Further, the separable thin-plate spline emulator, which accounts for the dependence between basis coefficients, provides substantially more realistic quantification of uncertainty, and is also computationally more tractable, allowing fast emulation. For high resolution output data, it also offers substantial predictive and computational ad- vantages over the tensor-product Gaussian process emulator
Frog foams and natural protein surfactants
Foams and surfactants are relatively rare in biology because of their potential to harm cell membranes and other delicate tissues. However, in recent work we have identified and characterized a number of natural surfactant proteins found in the foam nests of tropical frogs and other unusual sources. These proteins, and their associated foams, are relatively stable and bio-compatible, but with intriguing molecular structures that reveal a new class of surfactant activity. Here we review the structures and functional mechanisms of some of these proteins as revealed by experiments involving a range of biophysical and biochemical techniques, with additional mechanistic support coming from more recent site-directed mutagenesis studies
Networked Families
Presents survey results on the use of the Internet and ownership of cell phones and computers, by household type. Examines how technology ownership affects the frequency, form, purpose, and quality of communications among family members and friends
Gun Carrying Among Adolescents
Outdoor education is a promising educational field that can support indoor education and provide benefits beyond the evidentknowledge. Outdoor and indoor education together can formulate the ground for an integrated learning. In Greece, like manycountries, outdoor education and its potential contribution to the learning process have not been clearly and intentionally testedyet, even though the country tends to follow a progressive educational philosophy. This research focuses on the subject ofmathematics and explores the connections between the existing philosophy and practices of mathematics education in Greece andoutdoor education theory and practice. Following the method of content analysis, the connections were identified through theexistence of basic outdoor education concepts in the mathematics textbooks of the last three grades of primary school. Althoughthe expectations, because of the lack of personal experiences, could not be high, the application of outdoor education seems to befar from impossible in Greece. It could rather flourish even without any changes in the books, when its potentialities are realizedby the teachers
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