111 research outputs found
Towards The Sustainable City: The Impact Of Transport-Land Use Interactions, Deliverable 6. The Final Report.
Very few transport studies have been able to demonstrate that transport policy measures alone can improve sustainability by reducing fuel consumption and emissions below existing levels. There is therefore an increasing interest in the use of coordinated transport-land use policies, but a lack of understanding of relevant relationships. This research sought to obtain greater insight into these relationships. The main objectives were: (i) to increase our understanding of the impact of accessibility and environmental quality on individuals’ and firms’ location decisions; (ii) to use the findings of (i) to enhance a newly developed strategic transport and land use interaction model; (iii) to use the enhanced model to assess the implications for urban sustainability of the impact of transport policy on location choice; and (iv) to use the enhanced model to assess the relative performance of different combinations of transport and land use strategy.
There were two main strands to the work. The first involved the use of a newly developed strategic transport-land use model DELTA/START to test the effects of a range of values for environmental and accessibility coefficients. The tests were based on Edinburgh, and included several combinations of road pricing, fares reductions and light rail, and an alternative land use strategy. The second strand involved a literature review and survey work undertaken in Edinburgh using a stated preference approach to identify values for environmental indicators and accessibility to feed into the model.
The survey work of households and businesses was successful in producing values for environmental quality and accessibility. We found that changes in air quality were valued more highly than corresponding changes in noise levels. The survey also revealed some interesting issues that merit further investigation: deteriorations in environmental quality were valued more highly than improvements, there was a greater resistance to increases in council tax beyond current levels than up to current levels and valuations were higher where conditions were worse.
The transport strategies were predicted to induce considerable shifts in activity, with city centre populations increasing by up to 20%. However, these substantial changes in activity had relatively small impacts on the transport indicators. The results for the alternative land use scenario showed similar effects. Generally it appears, from the tests involving the strategic transport model that the effects on transport indicators of land use changes, whether induced through transport strategies or imposed through land use planning, are an order of magnitude lower than those of the transport strategies themselves. This is an important policy result since it calls into question how much can be achieved by pursuing coordinated land use and transport strategies
Evaluation of the use and non-use benefits of public transport: report number 1 – development of a survey methodology
This paper reports on the development of a survey methodology to discover the value people place on the retention of local public transport services, both for their own expected use and as a standby, for the use of others or for the benefits in terms of reduced congestion, improved environment and accessibility they might bring.
A survey of the literature suggested that numerous problems of potential bias would be faced. The most serious were likely to be strategic bias, starting point bias, information bias and social-norm bias. Other problems were choice of payment mechanism, how to obtain household rather than individual valuations and non-response bias.
Initially a set of exploratory interviews were undertaken. These confirmed that people were able to understand the issues involved, but that they had difficulty particularly with open-ended willingness to pay questions and with assigning values to different types of benefit. They were also sensitive to the payment mechanism, being very hostile to the idea of a subscription scheme.
Based on these interviews, attempts were made to design a self completion questionnaire. However, two major problems were encountered. One was the low level of response (20% or less). The second was evidence (confirmed by follow up interviews) of incomplete response, misunderstanding of questions and a failure to think through the full implications of the situations and responses postulated.
This led us to develop a new technique, based on hand delivery and collection of a travel diary, which was used as a basis for a follow-up interview. This enabled the interview to be structured towards the unique circumstances of the individual, to explore the options available as alternatives to the existing mode, and to obtain use and non use values in the context of a detailed discussion of the use and importance of local bus services
Evaluation of the Use and Non-Use Benefits of Public Transport: Report Number 2 – Application of the Method.
In this paper, we present results of a survey designed to discover the value people place on the retention of a bus service. The survey consisted of two parts; a travel diary, and a follow-up interview designed to explore respondents' reactions to removal of the bus services and the willingness to pay for its retention. The survey was undertaken in two contrasting areas: Hawksworth, in Leeds, a low income area of predominantly Council housing and Rainow, in Cheshire, a village with high car and home ownership. Most respondents in Hawksworth were regular bus users; the reverse was the case in Rainow.
Typically, it appeared that bus users enjoy a consumer surplus on their journeys of the order of 100% with a higher value for the small number of work journeys in Rainow. Non-use values appear to be very significant, with a higher valuation amongst non-users than users. On average, residents were willing to pay some 60 pence per week to preserve the route as a whole. In Hawksworth, the corresponding values were 50 pence for the specific route serving the estate, and 75 pence for the network as a whole. It was generally agreed that services to workplaces, shops, schools and medical facilities were the highest priority, with weekday peak and weekday busy time services taking priority over Saturdays, evening and Sundays. In terms of priority groups, pensioners were always ranked first; in general these were followed by the unemployed and children; non-users in Hawksworth however ranked the unemployed last.
The practical use of these results will be considered in a further project looking at actual and potential ways for ranking services for subsidy
The Optimisation of Integrated Urban Transport Strategies: Tests Based on Edinburgh
INTRODUCTION
Even with relatively simple model packages and modern computers, it is not feasible to test all combinations of model input variables to see which combination gives the 'best' outcome. Neither is it usually possible to solve the models analytically for the optimum. Consequently, there is a potential role for a methodology which takes as input the results from a relatively small number of runs of the model package and then models the response surface in the region containing the optimum, in such a way that it can be analytically solved for the optimum. This paper will set out such a methodology together with a Case Study
The Optimisation of Integrated Urban Transport Strategies: Tests Using Pluto
This working paper reports work indertaken on an EPSRC study, the optimisation of integrated urban transport strategies. It is the fist in a series of papers each reporting work using a different transport model. This paper is concerned with work using PLUTO, a transport model based on a hypothetical city, which can provide model runs quickly and cheaply.
PLUTO was used to experiment widely, examining paths towards an optimum when considering discrete policy variables, continuous policy variables and hybrids where several policy variables may be combined to form a strategy.
Our search for a method by which to reach an optimum solution uses regression analysis of carefully specified sets of model runs. We find that the use of statistical modelling techniques is extremely useful in pointing the way to an optimum, using only a limited number of model runs. However, care is necessary to ensure that the regression models are interpreted correctly
The Development of a Common Investment Appraisal for Urban Transport Projects.
In December 1990 we were invited by Birmingham City Council and Centro to submit a proposal for an introductory study of the development of a common investment appraisal for urban transport projects. Many of the issues had arisen during the Birmingham Integrated Transport Study (BITS) in which we were involved, and in the subsequent assessment of light rail schemes of which we have considerable experience. In subsequent discussion, the objectives were identified as being:- (i) to identify, briefly, the weaknesses with existing appraisal techniques; (ii) to develop proposals for common methods for the social cost-benefit appraisal of both urban road and rail schemes which overcome these weaknesses; (iii) to develop complementary and consistent proposals for common methods of financial appraisal of such projects; (iv) to develop proposals for variants of the methods in (ii) and (iii) which are appropriate to schemes of differing complexity and cost; (v) to consider briefly methods of treating externalities, and performance against other public sector goals, which are consistent with those developed under (ii) to (iv) above; (vi) to recommend work to be done in the second phase of the study (beyond March 1991) on the provision of input to such evaluation methods from strategic and mode-specific models, and on the testing of the proposed evaluation methods. Such issues are particularly topical at present, and we have been able to draw, in our study, on experience of:-
(i) evaluation methods developed for BITS and subsequent integrated transport studies (MVA) (ii) evaluation of individual light rail and heavy rail investment projects (ITS,MVA); (iii) the recommendations of AMA in "Changing Gear" (iv) advice to IPPR on appraisal methodology (ITS); (v) submissions to the House of Commons enquiry into "Roads for the Future" (ITS); (vi) advice to the National Audit Office (ITS) (vii) involvement in the SACTRA study of urban road appraisal (MVA, ITS
Use and Non-Use Benefits of Public Transport Systems - What is Their Relevance, Can They Be Valued?
Institute of Transport and Logistics Studies. Business School. The University of Sydney
Search for vectorlike B quarks in events with one isolated lepton, missing transverse momentum, and jets at √s = 8 TeV with the ATLAS detector
A search has been performed for pair production of heavy vectorlike down-type (B) quarks. The analysis explores the lepton-plus-jets final state, characterized by events with one isolated charged lepton (electron or muon), significant missing transverse momentum, and multiple jets. One or more jets are required to be tagged as arising from b quarks, and at least one pair of jets must be tagged as arising from the hadronic decay of an electroweak boson. The analysis uses the full data sample of pp collisions recorded in 2012 by the ATLAS detector at the LHC, operating at a center-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 20.3 fb −1 . No significant excess of events is observed above the expected background. Limits are set on vectorlike B production, as a function of the B branching ratios, assuming the allowable decay modes are B → Wt/Zb/Hb. In the chiral limit with a branching ratio of 100% for the decay B → Wt, the observed (expected) 95% C.L. lower limit on the vectorlike B mass is 810 GeV (760 GeV). In the case where the vectorlike B quark has branching ratio values corresponding to those of an SU(2) singlet state, the observed (expected) 95% C.L. lower limit on the vectorlike B mass is 640 GeV (505 GeV). The same analysis, when used to investigate pair production of a colored, charge 5/3 exotic fermion T 5/3 , with subsequent decay T 5/3 → Wt, sets an observed (expected) 95% C.L. lower limit on the T 5/3 mass of 840 GeV (780 GeV)
Search for W′→tb→qqbb decays in pp collisions at √s=8 TeV with the ATLAS detector
A search for a massive W′ gauge boson decaying to a top quark and a bottom quark is performed with the ATLAS detector in pp collisions at the LHC. The dataset was taken at a centre-of-mass energy of √s=8 TeV and corresponds to 20.3 fb−1 of integrated luminosity. This analysis is done in the hadronic decay mode of the top quark, where novel jet substructure techniques are used to identify jets from high-momentum top quarks. This allows for a search for high-mass W′ bosons in the range 1.5–3.0 TeV. b-tagging is used to identify jets originating from b-quarks. The data are consistent with Standard Model background-only expectations, and upper limits at 95 % confidence level are set on the W′→tb cross section times branching ratio ranging from 0.16pb to 0.33pb for left-handed W′ bosons, and ranging from 0.10pb to 0.21pb for W′ bosons with purely right-handed couplings. Upper limits at 95 % confidence level are set on the W′-boson coupling to tb as a function of the W′ mass using an effective field theory approach, which is independent of details of particular models predicting a W′boson
Measurement of the cross section for isolated-photon plus jet production in pp collisions at √s=13 TeV using the ATLAS detector
The dynamics of isolated-photon production in association with a jet in proton–proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb−1. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- algorithm with radius parameter and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon–jet invariant mass and the scattering angle in the photon–jet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements
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