The effects of speed cameras: How drivers respond

This study set out to examine the effects and effectiveness of various strategies related to the deployment of speed cameras, and to explore how different types of driver responded to cameras and perceived their operation. Recommendations for best deployment were to be considered. It was carried out between 1993 and 1996 after the Road Traffic Act 1991 authorised the use of automatic speed devices for the detection of offences. A series of 12 surveys arranged in five sets and having some cross-sectional and some longitudinal elements was undertaken together with some depth interviews, and self-report measures predominated. Five police forces helped to set up the research. In total 6879 drivers took part. The particular interventions focused upon comprised camera signing alone; two kinds of publicity campaign linked with speed camera deployment; prosecution following detection by speed camera; and the effects of cameras when first installed and over time.The Department of Environment, Transport and the Regions

Core drill's bit is replaceable without withdrawal of drill stem - A concept

Drill bit is divided into several sectors. When collapsed, the outside diameter is forced down the drill stem, when it reaches bottom the sectors are forced outward and form a cutting bit. A dulled bit is retracted by reversal of this procedure

Analysis-of-marginal-Tail-Means (ATM): a robust method for discrete black-box optimization

We present a new method, called Analysis-of-marginal-Tail-Means (ATM), for effective robust optimization of discrete black-box problems. ATM has important applications to many real-world engineering problems (e.g., manufacturing optimization, product design, molecular engineering), where the objective to optimize is black-box and expensive, and the design space is inherently discrete. One weakness of existing methods is that they are not robust: these methods perform well under certain assumptions, but yield poor results when such assumptions (which are difficult to verify in black-box problems) are violated. ATM addresses this via the use of marginal tail means for optimization, which combines both rank-based and model-based methods. The trade-off between rank- and model-based optimization is tuned by first identifying important main effects and interactions, then finding a good compromise which best exploits additive structure. By adaptively tuning this trade-off from data, ATM provides improved robust optimization over existing methods, particularly in problems with (i) a large number of factors, (ii) unordered factors, or (iii) experimental noise. We demonstrate the effectiveness of ATM in simulations and in two real-world engineering problems: the first on robust parameter design of a circular piston, and the second on product family design of a thermistor network

Uniformity Studies of Scintillator Tiles directly coupled to SiPMs for Imaging Calorimetry

We present a novel geometry of scintillator tiles developed for fiberless coupling to silicon photomultipliers (SiPMs) for applications in highly granular calorimeters. A high degree of uniformity of the tile response over the full active area was achieved by a drilled slit at the coupling position of the photon sensor with 2 mm, 4 mm and 5.5 mm in height, width and depth. Detailed measurements of the response to penetrating electrons were performed for tiles with a lateral size of 3 x 3 cm^2 and thicknesses of 5 mm and 3 mm.Comment: 6 pages, 8 figures, accepted by NIM

A Possible Nanometer-scale Computing Device Based on an Adding Cellular Automaton

We present a simple one-dimensional Cellular Automaton (CA) which has the property that an initial state composed of two binary numbers evolves quickly into a final state which is their sum. We call this CA the Adding Cellular Automaton (ACA). The ACA requires only 2N two-state cells in order to add any two N-1 bit binary numbers. The ACA could be directly realized as a wireless nanometer-scale computing device - a possible implementation using coupled quantum dots is outlined.Comment: 8 pages, RevTex, 3 Postscript figures. This version to appear in App. Phys. Let

Evolutionary quantum game

We present the first study of a dynamical quantum game. Each agent has a `memory' of her performance over the previous m timesteps, and her strategy can evolve in time. The game exhibits distinct regimes of optimality. For small m the classical game performs better, while for intermediate m the relative performance depends on whether the source of qubits is `corrupt'. For large m, the quantum players dramatically outperform the classical players by `freezing' the game into high-performing attractors in which evolution ceases.Comment: 4 pages in two-column format. 4 figure

Exact dynamical response of an N-electron quantum dot subject to a time-dependent potential

We calculate analytically the exact dynamical response of a droplet of N interacting electrons in a quantum dot with an arbitrarily time-dependent parabolic confinement potential \omega(t) and a perpendicular magnetic field. We find that, for certain frequency ranges, a sinusoidal perturbation acts like an attractive effective interaction between electrons. In the absence of a time-averaged confinement potential, the N electrons can bind together to form a stable, free-standing droplet.Comment: 10 pages, RevTex, 3 Postscript figures. This version to appear as a Rapid Communication in PR