Control of Congestion in Highly Saturated Networks: Development of Signal Timings

This working paper is one in a series of four describing a study of the control of traffic congestion in a network of highly saturated signalised junctions in Bangkok. Other papers in the series are: WP 248: Survey Design and Data Collection 250: Incidents and their Management 251: Experimental Results and Conclusions The study itself was a follow-up to a previous study already reported in WP 220, WP 221 and WP 222

Control of Congestion in Highly Saturated Networks: Working Paper 251 – Experimental Results and Conclusions

This working paper describes the results and conclusions drawn from experiments in traffic control carried out in Bangkok, Thailand, during a study of the control of highly saturated networks. Other papers in the series are WP 248 (Survey Design and Data Collection) WP 249 (Development of Signal Timings) and WP 250 (Incidents and their Management) This study formed a follow-up to an earlier study reported in WP 220, WP 221 and WP 222

An investigation into the comparative learning gain and ‘value added’ for students from widening participation and non-widening participation groups:a case study from sports degrees

Increasingly universities are expected to demonstrate the impact of students’ higher education experiences; learning gain is one of the metrics that can evidence this. The Scottish Funding Council (SFC) agrees Widening Participation (WP) objectives with the universities with an implicit expectation that Scottish higher education institutions (HEIs) work within their communities to enable those who could benefit from a university education to enrol. The Abertay sport programmes have historically supported students from diverse backgrounds. This case study focuses specifically on the graduate outcomes of WP and non-WP students graduating from these programmes in the years 2000–2015. An e-mail survey and departmental database of graduate destinations were linked with the student record. Analysis confirmed that those from WP backgrounds were equally as likely to gain a good degree as their non-WP counterparts and to be in graduate and/or sports employment. Longitudinal graduate outcomes are considered in the context of pedagogic strategy

The Uncertainty Relation in "Which-Way" Experiments: How to Observe Directly the Momentum Transfer using Weak Values

A which-way measurement destroys the twin-slit interference pattern. Bohr argued that distinguishing between two slits a distance s apart gives the particle a random momentum transfer \wp of order h/s. This was accepted for more than 60 years, until Scully, Englert and Walther (SEW) proposed a which-way scheme that, they claimed, entailed no momentum transfer. Storey, Tan, Collett and Walls (STCW) in turn proved a theorem that, they claimed, showed that Bohr was right. This work reviews and extends a recent proposal [Wiseman, Phys. Lett. A 311, 285 (2003)] to resolve the issue using a weak-valued probability distribution for momentum transfer, P_wv(\wp). We show that P_wv(\wp) must be wider than h/6s. However, its moments can still be zero because P_wv(\wp) is not necessarily positive definite. Nevertheless, it is measurable in a way understandable to a classical physicist. We introduce a new measure of spread for P_wv(\wp): half of the unit-confidence interval, and conjecture that it is never less than h/4s. For an idealized example with infinitely narrow slits, the moments of P_wv(\wp) and of the momentum distributions are undefined unless a process of apodization is used. We show that by considering successively smoother initial wave functions, successively more moments of both P_wv(\wp) and the momentum distributions become defined. For this example the moments of P_wv(\wp) are zero, and these are equal to the changes in the moments of the momentum distribution. We prove that this relation holds for schemes in which the moments of P_wv(\wp) are non-zero, but only for the first two moments. We also compare these moments to those of two other momentum-transfer distributions and \hat{p}_f-\hat{p}_i. We find agreement between all of these, but again only for the first two moments.Comment: 14 pages, 6 figures, submitted to J. Opt.