Bryophytes of Uganda : 2., new and interesting records

51 hepatics and 46 mosses are reported new to Uganda, including one moss new to Africa, one hepatic and two mosses new to mainland Africa, and 2 hepatics that are otherwise known only from their type collection

Vibrations of the propeller shaft and the rear axle of a passenger car

Digital analysis of the free-free bending vibrations of a propeller shaft and a beam-type rear axle are compared, for different theoretical models, with the results of rig tests. The relative importance of distributed mass, the coupling between the bending and torsional modes and the half shafts of the rear axle are discussed. The relation between the work completed and the programme of work in progress is given briefly at the end of the report

Pip and Pop: When auditory alarms facilitate visual change detection in dynamic settings

Dynamic and complex command and control situations often require the timely recognition of changes in the environment in order to detect potentially malicious actions. Change detection can be challenging within a continually evolving scene, and particularly under multitasking conditions whereby attention is necessarily divided between several subtasks. On-screen tools can assist with detection (e.g., providing a visual record of changes, ensuring that none are overlooked), however, in a high workload environment, this may result in information overload to the detriment of the primary task. One alternative is to exploit the auditory modality as a means to support visual change detection. In the current study, we use a naval air-warfare simulation, and introduce an auditory alarm to coincide with critical visual changes (in aircraft speed/direction) on the radar. We found that participants detected a greater percentage of visual changes and were significantly quicker to detect these changes when they were accompanied by an auditory alarm than when they were not. Furthermore, participants reported that mental demand was lower in the auditory alarm condition, and this was reflected in reduced classification omissions on the primary task. Results are discussed in relation to Wickens’ multiple resource theory of attention and indicate the potential for using the auditory modality to facilitate visual change detection

Inspection of the Lower Half of Wing Lap Joints with EMATs

Detection of fatigue cracks at the fastener holes in the lower portion of the C5A wing lap joint is complicated by lack of a direct line of access, and by the presence of fasteners and sealant material. Furthermore, any successful detection procedure must take into account the wide variation in the geometrical features of the joint. In this work, periodic permanent magnet EMATs (electromagnetic-acoustic transducers) have been employed to excite the n=o horizontally polarized shear mode of the skin at 200 kHz and 250 kHz. These modes are partially transmitted into the overlap region joined by the fastener. Spectral analysis of suitably time gated and apodized portions of the reflected waveform have allowed simulated cracks growing out of fastener holes to be detected, and preliminary sizing algorithms have been developed

Reproducing the general through the local: Lessons from poverty research

Central to research into the conduct of everyday life are issues of generalisation. This chapter focuses on three interrelated forms or manifestations of generalisation, which invoke issues around how macro-level structures and intergroup relations are reproduced through micro-level situations. First, theoretical generalisation constitutes our efforts to enlarge the significance of small-scale exemplars through research by relating local insights to the broader body of academic knowledge. Second, referential generalisation involves relating everyday artefacts produced by our research participants to the broader social context and intergroup relations at play. Third, empathetic generalisation involves promoting witnessing, recognition, and empathy towards people experiencing poverty by people who are not living in poverty. These three forms or elements of generalisation are central to the development of action strategies to address issues of poverty

DESIGN FOR A FAST, XFEL-QUALITY WIRE SCANNER

Abstract RadiaBeam Technologies has designed and manufactured a new wire scanner for high-speed emittance measurements of XFEL-type beams of energy 139 MeV. Using three 25-micron thick tungsten wires, this wire scanner measures vertical and horizontal beam size as well as transverse spatial correlation in one pass. The intensity of the beam at a wire position is determined from emitted bremsstrahlung photons as measured by a BGO scintillator system. The wires are transported on a two-ended support structure moved by a ball-screw linear stage. The doubleended structure reduces vibrations in the wire holder, and the two-bellows design negates the effects of air pressure on the motion. The expected minimum beam size measurable by this system is on the order of 10 microns with 0.1-micron accuracy. To achieve this, new algorithms are presented that reduce the effect of the non-zero thickness of the wire on the wire scan output. In addition, novel calculations are presented for determining the elliptical geometric parameters (vertical and horizontal beam size and correlation, or alternatively, the axis lengths and rotation) of the beam from the wire scanner measurements