11,159 research outputs found
Demand Forecasting for New Local Rail Services: A Case Study of a New Service Between Leicester and Burton-On- Trent
Preston, J. and Wardman, M. (1988) "Demand Forecasting for New
Local Rail Services: A Case Study of a New Service between
Leicester and Burton-on-Trent". Workina Paver 260, Institute for
Transport Studies, University of Leeds.
This paper assesses the potential for a new rail service between
Leicester and Burton-on-rent. In order to do this, three sets of
demand forecasts were produced. These were based on Revealed
Preference (RP) models that had been developed in West Yorkshire,
a Stated Intentions (SI) survey of the Leicester-Burton corridor
and Stated Preference (SP) models developed for the Ashby/
Coalville -and Outer Leicester areas. It was found that these
three approaches gave a wide range of forecasts but it was felt
that the SI survey, adjusted for the findings from the SP models,
were likely to give the most reliable estimates of usage. As a
result, it was concluded that, given patronage growth over time,
total usage of the line would amount to between 3,000 and 4,000
trips on an average day.
The demand forecasts were then used as input to an evaluation
framework which took into account capital costs, operating costs,
revenue and time savings. Even if actual usage reached the upper
level of our forecasts it was shown that, although operating
costs would be covered, only some of the capital costs would be
paid back. Consideration of user time savings strengthens the
case for the scheme but even so a return on capital would still
not be achieved. Therefore, it was concluded that the case for a
rail service between Leicester and Burton is, at best, marginal,
although a number of ways to continue the feasibility study are
suggested
Why is the nuclear symmetry energy so uncertain at supra-saturation densities?
Within the interacting Fermi gas model for isospin asymmetric nuclear matter,
effects of the in-medium three-body interaction and the two-body short-range
tensor force due to the meson exchange as well as the short-range
nucleon correlation on the high-density behavior of the nuclear symmetry energy
are demonstrated respectively in a transparent way. Possible physics origins of
the extremely uncertain nuclear symmetry energy at supra-saturation densities
are discussed.Comment: Added discussions and revised format. Version to appear in Phys. Rev.
C (2010
European Railway Comparisons: Final Report
The Institute for Transport Studies (ITS), University of Leeds and the British Railways Board (BRB) carried out a major comparative study of Western European railways in the late 1970s (BRB and University of Leeds, 1979). Follow-up work was carried out by ITS financed by the Social Science Research Council and reported by Nash (1985). It was deaded to revive this work at ITS for a number of reasons:
It is over ten years since the last set of comparisons (for 1981) were made at ITS and therefore a review of the changes in costs and productivity may be timely.
There has been a number of technical developments that make the use of statistical cost analysis more promising. These developments include the use of more flexible functional forms such as the translog, and the development of comprehensive total factor productivity indices (see, for example, Dodgson, 1985 and, more recently, Hensher and Waters, 1993).
There is increasing interest in the organisational structure of railway industries as a result of the 1988 Transport Act in Sweden, the EC directive 91/4-40 and the publication of proposals for privatising British Rail in July 1992 (see, for example, ECMT, 1993).
Given the explosion in information technology, there were some hopes that data availability would have improved.
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Solution of the Bohr hamiltonian for soft triaxial nuclei
The Bohr-Mottelson model is solved for a generic soft triaxial nucleus,
separating the Bohr hamiltonian exactly and using a number of different
model-potentials: a displaced harmonic oscillator in , which is solved
with an approximated algebraic technique, and Coulomb/Kratzer,
harmonic/Davidson and infinite square well potentials in , which are
solved exactly. In each case we derive analytic expressions for the
eigenenergies which are then used to calculate energy spectra.
Here we study the chain of osmium isotopes and we compare our results with
experimental information and previous calculations.Comment: 13 pages, 9 figure
Geology of the Snap Lake kimberlite intrusion, Northwest Territories, Canada: field observations and their interpretation
The Cambrian (523 Ma) Snap Lake hypabyssal kimberlite intrusion, Northwest Territories, Canada, is a complex segmented diamond-bearing ore-body. Detailed geological investigations suggest that the kimberlite is a multi-phase intrusion with at least four magmatic lithofacies. In particular, olivine-rich (ORK) and olivine-poor (OPK) varieties of hypabyssal kimberlite have been identified. Key observations are that the olivine-rich lithofacieshas a strong tendency to be located where the intrusion is thickest and that there is a good correlation between intrusion thickness, olivine crystal size and crystal content. Heterogeneities in the lithofacies are attributed to variations in intrusion thickness and structural complexities. The geometry and distribution of lithofacies points to magmaticco-intrusion, and flow segregation driven by fundamental rheological differences between the two phases. We envisage that the low-viscosity OPK magma acted as a lubricant for the highly viscous ORK magma. The presenceof such low-viscosity, crystal-poor magmas may explain how crystal-laden kimberlite magmas (>60 vol.%) are able to reach the surface during kimberlite eruptions. We also document the absence of crystal settling and the development of an unusual subvertical fabric of elongate olivine crystals, which are explained by rapid degassing-induced quench crystallization of the magmas during and after intrusio
Searching for low mass objects around nearby dMe radio stars
Nearby M-dwarfs are best suited for searches of low mass companions. VLBI
phase-referencing observations with sensitive telescopes are able to detect
radio star flux-densities of tenths of mJy as well as to position the star on
the sky with submilliarcsecond precision. We have initiated a long-term
observational program, using EVN telescopes in combination with NASA DSN
dishes, to revisit the kinematics of nearby, single M dwarfs. The precision of
the astrometry allows us to search for possible companions with masses down to
1 Jupiter mass. In this contribution we report preliminary results of the first
observation epochs, in which we could detect some of the radio stars included
in our program.Comment: Proceedings of the 6th European VLBI Network Symposium, Ros E.,
Porcas R.W., Lobanov A.P., & Zensus J.A. (eds.), MPIfR, Bonn, Germany, p.
255-258 (2002). 4 pages, 3 figures, needs evn2002.cl
Recommended from our members
A Tale of two Cities: A study of access and attitudes to food in the Deepdale and Ingol areas of Preston
Near-UV Observations of CS29497-030: New Constraints on Neutron-Capture Nucleosynthesis Processes
Employing spectra obtained with the new Keck I HIRES near-UV sensitive
detector, we have performed a comprehensive chemical composition analysis of
the binary blue metal-poor star CS29497-030. Abundances for 29 elements and
upper limits for an additional seven have been derived, concentrating on
elements largely produced via neutron-capture nucleosynthesis. Included in our
analysis are the two elements that define the termination point of the slow
neutron-capture process, lead and bismuth. We determine an extremely high value
of [Pb/Fe] = +3.65 +/- 0.07 (sigma = 0.13) from three features, supporting the
single-feature result obtained in previous studies. We also detect Bi for the
first time in a metal-poor star. Our derived Bi/Pb ratio is in accord with
those predicted from the most recent FRANEC calculations of the slow
neutron-capture process in low-mass AGB stars. We find that the neutron-capture
elemental abundances of CS29497-030 are best explained by an AGB model that
also includes very significant amounts of pre-enrichment of rapid
neutron-capture process material in the protostellar cloud out of which the
CS29497-030 binary system formed. Thus, CS29497-030 is both an ``r+s'' and
``extrinsic AGB'' star. Furthermore, we find that the mass of the AGB model can
be further constrained by the abundance of the light odd-element [Na/Fe] which
is sensitive to the neutron excess.Comment: 7 pages = 4 + 2 colour encapsulated postscript figures + 1 table; to
appear in ApJ Letters; additional jpeg figure available at
ftp://www.astro.caltech.edu/users/iii/cs2949703
Designing a road traffic model for the cross-sectoral analysis of future national infrastructure
This paper presents a UK national road traffic model developed as part of the ITRC MISTRAL - a large
interdisciplinary project of the Infrastructure Transitions Research Consortium (ITRC). The proposed
model includes passenger and freight vehicle flows on major UK roads and predicts future demand in the
form of an inter-zonal origin-destination matrix, using and elasticity-based simulation approach. An
important part of the model is the network assignment step during which predicted flows are assigned to
the road network. This allows for the assessment of road capacity utilisation and facilitates the
identification of "pinch points" where future infrastructure investments might be targeted. Several policy
interventions are studied in the paper, including road expansion with additional lanes, new road
development and vehicle electrification. The model also explicitly considers cross-sectoral
interdependencies with other infrastructure networks, primarily with the energy sector where the
transport sector is the largest consumer, the digital communications sector, water supply and waste
management. In future extensions, the model will also be able to estimate the environmental footprint
and assess the risk and resilience of the transport network. This model has the potential to inform policy
makers about the long-term performance of UK road infrastructure, considering a range of possible
future scenarios for population growth, technological innovation and climate change
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