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Hie est Wadard: Vassal of Odo of Bayeux or Miles and Frater of St Augustine's, Canterbury?
The Politics of Misadventure at Camelot
A third of the way through La mort le roi Artu (c.1230), an early thirteenth-century Old French prose romance that concludes the Lancelot Grail Cycle, ‘the greatest misadventure in the world’ takes place at Camelot, the court of King Arthur of Logres. Although the poisoning episode, as I refer to it here, is extraordinarily complex and difficult to interpret, the following summary will suffice for the moment. While Queen Guinevere is eating in her chamber with Arthur’s nephew Gawain and many other knights of the Round Table, a knight called Avarlan is plotting in another room to poison Gawain, whom he hates for reasons that are never explained. Dispatching a servant to give a poisoned fruit to the queen, Avarlan expects her to pass it to Gawain, a particular favorite of hers, who will eat it and die. But Guinevere – who is not watching out for ‘treason’ – gives the fruit to a knight called Gaheris the White, brother of Mador de la Porte, who accepts it out of love for her. Taking a bite, he immediately drops dead. Astonished by this ‘marvel’, the queen and the other knights all jump up from the table. Seeing the dead knight, the queen is grief-stricken about this ‘misadventure’ (62.37) and does not know what to do, ‘because it was seen by so many worthy men that she could not deny it’ (62.38–40)
The Medieval English County Court
A Review of The County Courts of Medieval England, 1150-1350 by Robert C. Palme
Law of refraction for generalised confocal lenslet arrays
We derive the law of generalised refraction for generalised confocal lenslet
arrays, which are arrays of misaligned telescopes. We have implemented this law
of refraction in TIM, a custom open-source ray tracer.Comment: 4 pages, 3 figure
Including design in e-manufacturing
This paper reviews major issues in the implementation of e-manufacturing, particularly the design aspects. It will examine recent progress, drawing out particular issues that are being addressed. Use will be made of the work by the author and colleagues to devise rule-based design and Internet-based control of machines to illustrate how these developments affect the integrated e-manufacturing environment. A dynamic Simulink model of the way e-manufacture is affected by overall design delays is used to evaluate general solutions for partial and complete e-based companies. These models show how changing to improved designs reduces WI
Millimeter radiation from a 3D model of the solar atmosphere II. Chromospheric magnetic field
We use state-of-the-art, three-dimensional non-local thermodynamic
equilibrium (non-LTE) radiative magnetohydrodynamic simulations of the quiet
solar atmosphere to carry out detailed tests of chromospheric magnetic field
diagnostics from free-free radiation at millimeter and submillimeter
wavelengths (mm/submm). The vertical component of the magnetic field was
deduced from the mm/submm brightness spectra and the degree of circular
polarization synthesized at millimeter frequencies. We used the frequency bands
observed by the Atacama Large Millimeter/Submillimeter Array (ALMA) as a
convenient reference. The magnetic field maps obtained describe the
longitudinal magnetic field at the effective formation heights of the relevant
wavelengths in the solar chromosphere. The comparison of the deduced and model
chromospheric magnetic fields at the spatial resolution of both the model and
current observations demonstrates a good correlation, but has a tendency to
underestimate the model field. The systematic discrepancy of about 10 percent
is probably due to averaging of the restored field over the heights
contributing to the radiation, weighted by the strength of the contribution. On
the whole, the method of probing the longitudinal component of the magnetic
field with free-free emission at mm/submm wavelengths is found to be applicable
to measurements of the weak quiet-Sun magnetic fields. However, successful
exploitation of this technique requires very accurate measurements of the
polarization properties (primary beam and receiver polarization response) of
the antennas, which will be the principal factor that determines the level to
which chromospheric magnetic fields can be measured. Consequently,
high-resolution and high-precision observations of circularly polarized
radiation at millimeter wavelengths can be a powerful tool for producing
chromospheric longitudinal magnetograms.Comment: 12 pages, 13 figures, accepted for publication in A&
Fertility control as a means of controlling bovine tuberculosis in badger (Meles meles) populations in south-west England: predictions from a spatial stochastic simulation model
A spatial stochastic simulation model was used to assess the potential of fertility control, based on a yet-to-be-developed oral bait-delivered contraceptive directed at females, for the control of bovine tuberculosis in badger populations in south-west England. The contraceptive had a lifelong effect so that females rendered sterile in any particular year remained so for the rest of their lives. The efficacy of fertility control alone repeated annually for varying periods of time was compared with a single culling operation and integrated control involving an initial single cull followed by annually repeated fertility control. With fertility control alone, in no instance was the disease eradicated completely while a viable badger population (mean group size of at least one individual) was still maintained. Near eradication of the disease (less than 1% prevalence) combined with the survival of a minimum viable badger population was only achieved under a very limited set of conditions, either with high efficiency of control (95%) over a short time period (1-3 years) or a low efficiency of control (20%) over an intermediate time period (10-20 years). Under these conditions, it took more than 20 years for the disease to decline to such low levels. A single cull of 80% efficiency succeeded in near eradication of the disease (below 1% prevalence) after a period of 6-8 years, while still maintaining a viable badger population. Integrated strategies reduced disease prevalence more rapidly and to lower levels than culling alone, although the mean badger group size following the onset of control was smaller. Under certain integrated strategies, principally where a high initial cull (80%) was followed by fertility control over a short (1-3 year) time period, the disease could be completely eradicated while a viable badger population was maintained. However, even under the most favourable conditions of integrated control, it took on average more than 12 years following the onset of control for the disease to disappear completely from the badger population. These results show that whilst fertility control would not be a successful strategy for the control of bovine tuberculosis in badgers if used alone, it could be effective if used with culling as part of an integrated strategy. This type of integrated strategy is likely to be more effective in terms of disease eradication than a strategy employing culling alone. However, the high cost of developing a suitable fertility control agent, combined with the welfare and conservation implications, are significant factors which should be taken into account when considering its possible use as a means of controlling bovine tuberculosis in badger populations in the UK
Windows into Non-Euclidean Spaces
Two microlens arrays that are separated by the sum of their focal lengths form arrays of micro-telescopes. Parallel light rays that pass through corresponding lenses remain parallel, but the direction of the transmitted light rays is different. This remains true if corresponding lenses do not share an optical axis (i.e. if the two microlens arrays are shifted with respect to each other). The arrays described above are examples of generalized confocal lenslet arrays, and the light-ray-direction change in these devices is well understood [Oxburgh et al., Opt. Commun. 313, 119 (2014)]. Here we show that such micro-telescope arrays change light-ray direction like the interface between spaces with different metrics. To physicists, the concept of metrics is perhaps most familiar from General Relativity (where it is applied to spacetime, not only space, like it is here) and Transformation Optics [Pendry et al., Science 312, 1780 (2006)], where different materials are treated like spaces with different optical metrics. We illustrate the similarities between micro-telescope arrays and metric interfaces with raytracing simulations. Our results suggest the possibility of realising transformation-optics devices with micro-telescope arrays, which we investigate elsewhere
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