Bubble Measurements Downstream of Hydraulic Jumps

A phase Doppler anemometer (PDA) system was used to measure the velocity profiles and air bubble size distributions downstream of two-dimensional hydraulic jumps for different upstream flow conditions in a 1.92m long laboratory flume. The PDA detected bubbles from 1 to 500 [microns] in diameter, and more were found at the bottom of the downstream flow near the elevation of the upstream free surface. This distribution was more marked for smaller bubbles, those with diameters less that 100 [microns]. The migration of the bubbles is controlled by the effects of buoyancy and by turbulent mixing; the relative magnitude of their effects on bubble distribution depends strongly on bubble size, and also on the energy of the upstream flow

New light on the ‘Drummer of Tedworth’: conflicting narratives of witchcraft in Restoration England

This paper presents a definitive text of hitherto little-known early documents concerning ‘The Drummer of Tedworth’, a poltergeist case that occurred in 1662-3 and became famous not least due to its promotion by Joseph Glanvill in his demonological work, Saducismus Triumphatus. On the basis of these and other sources, it is shown how responses to the events at Tedworth evolved from anxious piety on the part of their victim, John Mompesson, to confident apologetic by Glanvill, before they were further affected by the emergence of articulate scepticism about the case

Strategic Sequences of Arguments for Persuasion Using Decision Trees

Persuasion is an activity that involves one party (the persuader) trying to induce another party (the persuadee) to believe or do something. For this, it can be advantageous forthe persuader to have a model of the persuadee. Recently, some proposals in the field of computational models of argument have been made for probabilistic models of what the persuadee knows about, or believes. However, these developments have not systematically harnessed established notions in decision theory for maximizing the outcome of a dialogue. To address this, we present a general framework for representing persuasion dialogues as a decision tree, and for using decision rules for selecting moves. Furthermore, we provide some empirical results showing how some well-known decision rules perform, and make observations about their general behaviour in the context of dialogues where there is uncertainty about the accuracy of the user model

Computationally viable handling of beliefs in arguments for persuasion

Computational models of argument are being developed to capture aspects of how persuasion is undertaken. Recent proposals suggest that in a persuasion dialogue between some agents, it is valuable for each agent to model how arguments are believed by the other agents. Beliefs in arguments can be captured by a joint belief distribution over the arguments and updated as the dialogue progresses. This information can be used by the agent to make more intelligent choices of move in the dialogue. Whilst these proposals indicate the value of modelling the beliefs of other agents, there is a question of the computational viability of using a belief distribution over all the arguments. We address this problem in this paper by presenting how probabilistic independence can be leveraged to split this joint distribution into an equivalent set of distributions of smaller size. Experiments show that updating the belief on the split distribution is more efficient than performing updates on the joint distribution

The Stellar and Gas Kinematics of Several Irregular Galaxies

We present long-slit spectra of three irregular galaxies from which we determinethe stellar kinematics in two of the galaxies (NGC 1156 and NGC 4449) and ionized-gas kinematics in all three (including NGC 2366). We compare this to the optical morphology and to the HI kinematics of the galaxies. In the ionized gas, we see a linear velocity gradient in all three galaxies. In NGC 1156 we also detect a weak linear velocity gradient in the stars of (5+/-1/sin i) km/s/kpc to a radius of 1.6 kpc. The stars and gas are rotating about the same axis, but this is different from the major axis of the stellar bar which dominates the optical light of the galaxy. In NGC 4449 we do not detect organized rotation of the stars and place an upper limit of (3/sin i) km/s/kpc to a radius of 1.2 kpc. For NGC 4449, which has signs of a past interaction with another galaxy, we develop a model to fit the observed kinematics of the stars and gas. In this model the stellar component is in a rotating disk seen nearly face-on while the gas is in a tilted disk with orbits whose planes precess in the gravitational potential. This model reproduces the apparent counter-rotation of the inner gas of the galaxy. The peculiar orbits of the gas are presumed due to acquisition of gas in the past interaction.Comment: To be published in ApJ, November 20, 200

A comparative analysis of the industrial relations experiences of Indigenous and other Australian workers

Indigenous employment policy needs to be informed by a good understanding of the industrial relations culture of workplaces. For example, the local industrial relations environment is a major factor determining wages, job conditions and the quality of workplace life. This study contrasts the experience of industrial relations for Indigenous and non-Indigenous workers in workplaces with some Indigenous employees. The Australian Workplace Industrial Relations Survey (AWIRS) 1995 is the first publicly released dataset that permits analysts to directly examine the industrial relations environment in firms that employ Indigenous Australians. Information from the AWIRS employee survey and AWIRS Employee Relations Managers survey are used in the analysis

Band offsets in Si/Si1–x–yGexCy heterojunctions measured by admittance spectroscopy

We have used admittance spectroscopy to measure conduction-band and valence-band offsets in Si/Si1–xGex and Si/Si1–x–yGexCy heterostructures grown by solid-source molecular-beam epitaxy. Valence-band offsets measured for Si/Si1–xGex heterojunctions were in excellent agreement with previously reported values. Incorporation of C into Si1–x–yGexCy lowers the valence- and conduction-band-edge energies compared to those in Si1–xGex with the same Ge concentration. Comparison of our measured band offsets with previously reported measurements of energy band gaps in Si1–x–yGexCy and Si1–yCy alloy layers indicate that the band alignment is Type I for the compositions we have studied and that our measured band offsets are in quantitative agreement with these previously reported results

Industrial relations in workplaces employing Indigenous Australians

The enactment of the Workplace Relations Act 1996 by the Howard Government represented an acceleration in the pace of industrial relations reform. Amid these significant and widespread legislative developments, little attention was paid to the plight of groups traditionally disadvantaged in the labour market-including Indigenous people. The Australian Workplace Industrial Relations Survey (AWIRS) 1995 is the first publicly released data set that permits analysts to directly examine the industrial relations environment in firms that employ Indigenous Australians. Information from the AWIRS employee survey and AWIRS Employee Relations Managers survey are used in the analysis