Wilson loops in warped resolved deformed conifolds

We calculate quark–antiquark potentials using the relationship between the expectation value of the Wilson loop and the action of a probe string in the string dual. We review and categorise the possible forms of the dependence of the energy on the separation between the quarks. In particular, we examine the possibility of there being a minimum separation for probe strings which do not penetrate close to the origin of the bulk space, and derive a condition which determines whether this is the case. We then apply these considerations to the flavoured resolved deformed conifold background of Gaillard et al. (2010) [8]. We suggest that the unusual behaviour that we observe in this solution is likely to be related to the IR singularity which is not present in the unflavoured case.     

Wave propagation in circular cylindrical shells with periodic axial curvature

The propagation of longitudinal and flexural waves in axisymmetric circular cylindrical shells with periodic circular axial curvature is studied using a finite element method previously developed by the authors. Of primary interest is the coupling of these wave modes due to the periodic axial curvature which results in the generation of two types of stop bands not present in straight circular cylinders. The first type is related to the periodic spacing and occurs independently for longitudinal and flexural wave modes without coupling. However, the second type is caused by longitudinal and flexural wave mode coupling due to the axial curvature. A parametric study is conducted where the effects of cylinder radius, degree of axial curvature, and periodic spacing on wave propagation characteristics are investigated. It is shown that even a small degree of periodic axial curvature results in significant stop bands associated with wave mode coupling. These stop bands are broad and conceivably could be tuned to a specific frequency range by judicious choice of the shell parameters. Forced harmonic analyses performed on finite periodic structures show that strong attenuation of longitudinal and flexural motion occurs in the frequency ranges associated with the stop bands of the infinite periodic structure.     

Analytical methods for the environmental quantification of uranium isotopes: Method of validation and environmental application

The use of depleted uranium in military ordinance has led to an increasing need to determine isotope-specific uranium concentrations in environmental matrices. To this end, gamma-ray spectrometry, ICP-MS and INAA methods have been validated, in accordance with the ISO 17025 standard. Reporting limits of 0.21 (U-235) and 0.91 (U-238) ng/L were obtained by ICP-MS analysis of water. Higher reporting limits were obtained for INAA (U-238 only) validations of water and gamma-ray spectrometric validations of soil and water. Accredited methods have been used to determine uranium concentration and isotope ratio of samples obtained from the Defence Research and Development Canada Valcartier, Quebec.     

Environmental radionuclide monitoring programme

As part of Canada’s international commitment for the collective defence of allied nations, nuclear submarines from allied nations berth at three approved locations on both east and west coasts of Canada. In the case of any untoward event, a nuclear emergency response (NER) organisation has been established. In addition, regular sampling of the coastal environment is undertaken as the Environmental Radionuclide Monitoring Programme (ERMP). This continuing effort consists of a long-term programme and a visit sub-programme. In the former, samples are ocean sediment, seawater, aquatic plants and sealife; in the latter, samples are seawater taken before, during and after each visit. Samples are collected according to a prescribed schedule and follow a chain of custody to the accredited laboratory in the SLOWPOKE-2 Facility at RMC. Counting and analyses are done by gamma-ray spectroscopy by the Analytical Services Group (ASG) at RMC. With most results below detection limit, the safety of the NPV visits is assured.     

A set-up, calibration, acquisition and analysis program (SCAAP) for gamma-ray spectroscopy

A computer program entitled SCAAP (Set-up, Calibration, Acquisition and Analysis Program) has been designed to make gamma-ray spectroscopy easily useable by staff in laboratories at the Slowpoke-2 Facility at RMC and in support of the Canadian Forces Nuclear Emergency Response Teams (NERTs). The former group utilises gamma-ray spectroscopy for neutron activation analysis (NAA), while the latter may need to have inhalation dose rates calculated. The intent of this program, written using Microsoft Visual Basic, is to provide a simplified interface between the operator and the spectroscopy equipment and to provide the calculations necessary to produce results quickly. There are five sections (Setup, Calibrate, Acquire, Analyse and NAA) of which the first four are linked. In these sections, a checklist of procedures is presented and automated for the user to set up and calibrate the equipment and then to analyse spectra to provide various dose rates. In the unlinked section, NAA, gamma-ray spectra are analysed to provide elemental concentrations in samples.     

Domain representability and the Choquet game in Moore and BCO-spaces

In this paper we investigate the role of domain representability and Scott-domain representability in the class of Moore spaces and the larger class of spaces with a base of countable order. We show, for example, that in a Moore space, the following are equivalent: domain representability; subcompactness; the existence of a winning strategy for player α (= the nonempty player) in the strong Choquet game Ch(X); the existence of a stationary winning strategy for player α in Ch(X); and Rudin completeness. We note that a metacompact ?ech-complete Moore space described by Tall is not Scott-domain representable and also give an example of ?ech-complete separable Moore space that is not co-compact and hence not Scott-domain representable. We conclude with a list of open questions.     

Computational modelling of variably saturated flow in porous media with complex three‐dimensional geometries

A computational procedure is presented for solving complex variably saturated flows in porous media, that may easily be implemented into existing conventional finite‐volume‐based computational fluid dynamics codes, so that their functionality might be geared upon to readily enable the modelling of a complex suite of interacting fluid, thermal and chemical reaction process physics. This procedure has been integrated within a multi‐physics finite volume unstructured mesh framework, allowing arbitrarily complex three‐dimensional geometries to be modelled. The model is particularly targeted at ore heap‐leaching processes, which encounter complex flow problems, such as infiltration into dry soil, drainage, perched water tables and flow through heterogeneous materials, but is equally applicable to any process involving flow through porous media, such as in environmental recovery processes. The computational procedure is based on the mixed form of the classical Richards equation, employing an adaptive transformed mixed algorithm that is numerically robust and significantly reduces compute (or CPU) time. The computational procedure is accurate (compares well with other methods and analytical data), comprehensive (representing any kind of porous flow model), and is computationally efficient. As such, this procedure provides a suitable basis for the implementation of large‐scale industrial heap‐leach models. Copyright © 2005 John Wiley & Sons, Ltd.     

Ein constantes Wasserbad

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