Results of a UK industrial tribological survey

During the summer of 2012, the National Centre for Advanced Tribology at Southampton (nCATS) undertook a UK-wide industrial tribological survey in order to assess the explicit need for tribological testing within the UK. The survey was designed and implemented by a summer intern student, Mr Simon King, under the supervision of Drs John Walker and Terry Harvey and supported by the director of nCATS, Professor Robert Wood. The survey built upon on two previous tribological surveys conducted through the National Physical Laboratory (NPL) during the 1990’s. The aim was to capture a snapshot of the current use of tribological testing within UK industry and its perceived reliability in terms of the test data generated. The survey also invited participants to speculate about how UK tribology could improve its approach to testing. The survey was distributed through the nCATS industrial contact list, which comprises of over 400 contacts from a broad spectrum of commercial industries. The Institute of Physics (IOP) tribology group also assisted by distributing the survey to its membership list. A total of 60 responses were received for the survey, out of which 39 had fully completed the questionnaire. Participants came from a broad spread of industrial backgrounds, with the energy sector having the highest representation. Only 40% of respondents were dedicated tribologists/surface engineers, again reflecting the multi-disciplinary nature of the field. It was found that the companies that had the highest annual turnover also appeared to expend the most on tribology. The majority of respondents indicated that as a percentage of turnover tribology accounted for less than 1%, however the lack of hard figures only for tribology make this a conservative estimate. The greatest concern in relation to tribology of those who responded was the cost; however the influence of legislation and product reliability were also driving factors. Abrasive wear was still considered the number one tribological wear mechanism, with sliding contacts ranking as the most common type of wear interface. Metallic and hard coated surfaces were the most commonly encountered type of material suffering from tribological wear phenomena. Laboratory scale testing was a significant part of introducing a new tribological component, however component specific testing was considered the most reliable form of testing a new component over standardised test geometries. Overall there appeared to be much potential for improving the reliability of tribological test data, with most respondents indicating that simply more testing was not the best perceived approach to improving tribological data but rather more reliable, representative tests with improved knowledge capture. Most companies possessed an internal database to assist them with tribological information; however, many also expressed a strong desire for the use of a commercial or national database, although the format this might take was less clear. Opinions appeared split as to whether there would be a collective willingness to contribute to a centralised database, presumably on the grounds on the sensitivity of data

The impact of language factors on learner achievement in Science

South African learner achievement remains poor, despite large investment in schooling over the last two decades. Literature and research findings offer no single explanation or solution. In this article, the authors explored the relative contribution of specific language factors such as the role of home- and school-language equivalence, cultural and economic capital, and other school and classroom factors to Science achievement. The analysis identified specific language and/or contextual factors having the biggest influence on learner achievement. This was achieved through secondary analysis of South African Grade Nine (N = 12,000) data from the Trends in International Mathematics and Science Study (TIMSS) 2011. Multiple-regression modelling using contextual and achievement data suggested that home- and school-language equivalence and how frequently learners used the school language at home were strongly associated with the Science achievement results of Grade Nine learners in South Africa. Several other language factors that could be seen as cultural capital, beyond broader economic capital, some classroom-related contextual conditions and selected school-level factors, also showed strong influences. It is concluded that language, teacher training, and broader economic policy changes and their thorough implementation are required to address these concerns.Keywords: cultural capital; economic capital; home language; language factors; language of assessment; language of learning; language of teaching; Science achievement; Trends in International Mathematics and Science Study (TIMSS

Spin dependent D-brane interactions and scattering amplitudes in matrix theory

Spin interactions beteween two moving Dp-branes are analyzed using the Green-Schwarz formalism of boundary states. This approach turns out to be extremely efficient to compute all the spin effects related by supersymmetry to the leading v^4/r^7-p term. All these terms are shown to be scale invariant, supporting a matrix model description of supergravity interactions. By employing the LSZ reduction formula for matrix theory and the mentioned supersymmetric effective potential for D0-branes, we compute the t-pole of graviton-graviton and three form-three form scattering in matrix theory. The results are found to be in complete agreement with tree level supergravity in the corresponding kinematical regime and provide, moreover, an explicit map between these degrees of freedom in both theories.Comment: 8 pages, no figures, talk presented at the conference "Quantum aspects of gauge theories, supergravity and unification", Corfu, Greece, to appear in the proceeding

A typological study of Egyptian wooden statues of the Old Kingdom

A corpus of 217 wooden statues dating from the Egyptian Old Kingdom is examined and discussed in detail. 127 statues have been dated to individual reigns within the Old Kingdom and are placed in chronological order (Catalogue A). They form the basis of a chronological feature list. Using the dating criteria from the feature list, and by drawing parallels with Catalogue A, a further 75 statues (Catalogue B) have been assigned to individual reigns within the Old Kingdom. New features from Catalogue B are then added to the chronological feature list. Catalogue C comprises statues which have no parallels in Catalogue A , but do sometimes have a parallel in Catalogue B, and which in the absence so far of evidence to the contrary, may be assigned to the Old Kingdom. Appendix I discusses the texts inscribed on 51 of the statues. These consist of the names and titles of the tomb owner. The texts are usually inscribed on the bases, but in two instances they are on the skirt, and once on the sceptre. The titles are examined in detail to see whether their date range is consistent with the dates suggested in the text. Unfortunately the inscriptions give no further dating assistance. The phrase im3hw hr is examined in detail and it emerges that its use changed over time. Appendix 2 is a discussion of the material of the statues, as far as this is known. Only 8 statues have been scientifically analysed, a further 4 have been identified visually, and another 2 have unconfirmed analyses. From this meagre information it emerges that indigenous woods were preferred to imported woods. The most popular indiginous woods are sycamore and acacia. Appendix 3 is a table of the dating features based on Catalogue A which, when applied to statues not in the corpus, can assist in assigning a date to them

Open Heterotic Strings

We classify potential cosmic strings according to the topological charge measurable outside the string core. We conjecture that in string theory it is this charge that governs the stability of long strings. This would imply that the SO(32) heterotic string can have endpoints, but not the E_8 x E_8 heterotic string. We give various arguments in support of this conclusion.Comment: 15 pages. v.2: typos, references correcte

Physiological and morphological determinants of maximal expiratory flow in chronic obstructive lung disease

Maximal expiratory flow in chronic obstructive pulmonary disease (COPD) could be reduced by three different mechanisms; loss of lung elastic recoil, decreased airway conductance upstream of flow-limiting segments; and increased collapsibility of airways. We hypothesized that decreased upstream conductance would be related to inflammation and thickening of the airway walls, increased collapsibility would be related to decreased airway cartilage volume, and decreased collapsibility to inflammation and thickening of the airway walls. Lung tissue was obtained from 72 patients with different degrees of COPD, who were operated upon for a solitary peripheral lung lesion. Maximal flow-static recoil (MFSR) plots to estimate upstream resistance and airway collapsibility were derived in 59 patients from preoperatively measured maximal expiratory flow-volume and pressure-volume curves. In 341 transversely cut airway sections, airway size, airway wall dimensions and inflammatory changes were measured. Airflow obstruction correlated with lung elastic recoil and the MFSR estimate of airway conductance but not to airway collapsibility or to the amount of airway cartilage. The upstream conductance decreased as the inner wall became thicker. Airway collapsibility did not correlate with the amount of airway cartilage, inflammation, or airway wall thickness. We conclude that the maximal flow-static recoil model does not adequately reflect the collapsibility of the flow-limiting segment

An analysis of TIMSS 2015 science reading demands

This study investigated the reading demands of restricted-use items1 administered to South African Grade 9 learners as part of the Trends in International Mathematics and Science Study (TIMSS) 2015. The method proposed by Mullis, Martin and Foy (2013) was used to categorise items into low, medium and high readability groups. The Knowing domain contained mostly low readability items, the Applying domain was almost equally medium and high readability items, with the Reasoning domain containing mostly high readability items. Results show significant differences between the percentage correctly answered between the low and high categories and between the medium and high categories. However, the full impact of reading demand on performance cannot be fully analysed without cross-reference to English proficiency. Nevertheless, the higher the readability, the greater the chance for learners to answer incorrectly. A continued expected low performance for most South African learners is implied.http://journals.ufs.ac.za/index.php/pieam2021Science, Mathematics and Technology Educatio

Poultry Houses and Poultry Equipment for Texas.

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