Engine non-containment: UK risk assessment methods

More realistic guideline data must be developed for use in aircraft design in order to comply with recent changes in British civil airworthiness requirements. Unrealistically pessimistic results were obtained when the methodology developed during the Concorde SST certification program was extended to assess catastrophic risks resulting from uncontained engine rotors

Through the Looking Glass:A Comparative Analysis of the CareerPatterns of Rural Female Administratorsin Saskatchewan and Texas

This article stems from research that examined the effect of the rural context on the career patterns of female administrators in rural public school divisions in the province of Saskatchewan, Canada, and in the state of Texas, United States. These two studies examined (a) the nature of rural communities and its relationship to women’s career paths in educational administration, and (b) barriers and supports faced by female administrators. The purpose of this article is to outline the findings of the study in relation to emergent issues for administration by women in rural areas.Cet article découle d’une recherche portant sur l’effet du contexte rural sur le profil de carrières d’administratrices dans des divisions scolaires rurales en Saskatchewan, au Canada, et dans l’état du Texas, EUA. La recherche visait: (a) la nature des communautés rurales et le rapport entre celle-ci et le profil de carrières des administratrices dans le domaine de l’éducation, et (b) les éléments qui se sont posés en obstacles aux administratrices et ceux qui leur ont apporté un appui. L’objectif de cet article est de tracer les grandes lignes de cette étude par rapport aux questions émergentes qui touchent les femmes en administration dans les régions rurales

Shining Lonely Stars? Career Patterns of Rural Texas Female Administrators

This paper stems from research that examined the impact of the rural context upon the career patterns of women educational administrators in rural public school districts in the state of Texas. The study examined two pertinent issues for women in rural education: (a) the nature of rural communities and its relationship to female career paths in educational administration, and (b) barriers and supports faced by female administrators in the rural context. The purpose of this paper will be to outline the findings of the study in relation to the emergent issues for rural female administrators

Effects of high energy photon emissions in laser generated ultra-relativistic plasmas: real-time synchrotron simulations

We model the emission of high energy photons due to relativistic charged particle motion in intense laser-plasma interactions. This is done within a particle-in-cell code, for which high frequency radiation normally cannot be resolved due to finite time steps and grid size. A simple expression for the synchrotron radiation spectra is used together with a Monte-Carlo method for the emittance. We extend previous work by allowing for arbitrary fields, considering the particles to be in instantaneous circular motion due to an effective magnetic field. Furthermore we implement noise reduction techniques and present validity estimates of the method. Finally, we perform a rigorous comparison to the mechanism of radiation reaction, and find the emitted energy to be in excellent agreement with the losses calculated using radiation reaction

Teaching Principals in Small Rural Schools: “My Cup Overfloweth”

This paper presents the results of interviews with 12 Manitoba and Alberta rural teaching principals regarding their leadership practices in small schools. The overwhelming theme mentioned by these teaching principals was the joy and sense of purpose they found in the relationships they cultivated with children, staff, and community members because of the ‘advantages’ they had working in small schools. The paper details the small schools context within which teaching principals are working in these two provinces and outlines the role of reciprocal relationality that is central to their leadership efforts in small rural schools.Cet article présente les résultats d’entrevues auprès de douze directeurs-enseignants d’écoles rurales au Manitoba et en Alberta portant sur les pratiques de leadership dans les petites écoles. Le thème dominant qui en est ressorti est celui de la joie et le sentiment d’un but à atteindre qu’ils retiraient des rapports entretenus avec les enfants, le personnel et les membres de la communauté et qu’ils associaient aux « bienfaits » de travailler dans une petite école. L’article décrit en détail le contexte scolaire dans lequel travaillent les directeurs-enseignants dans ces deux provinces, et dresse un portrait du rôle de la relationnalité réciproque qui est au centre de leurs efforts comme dirigeants de petites écoles en milieu rural.

Testing Gravity in the Outer Solar System: Results from Trans-Neptunian Objects

The inverse square law of gravity is poorly probed by experimental tests at distances of ~ 10 AUs. Recent analysis of the trajectory of the Pioneer 10 and 11 spacecraft have shown an unmodeled acceleration directed toward the Sun which was not explained by any obvious spacecraft systematics, and occurred when at distances greater than 20 AUs from the Sun. If this acceleration represents a departure from Newtonian gravity or is indicative of an additional mass distribution in the outer solar system, it should be detectable in the orbits of Trans-Neptunian Objects (TNOs). To place limits on deviations from Newtonian gravity, we have selected a well observed sample of TNOs found orbiting between 20 and 100 AU from the Sun. By examining their orbits with modified orbital fitting software, we place tight limits on the perturbations of gravity that could exist in this region of the solar system.Comment: 20 pages, 4 figures, 2 tables, uses AASTex v5.x macro

Thermodynamics of a Heavy Ion-Irradiated Superconductor: the Zero-Field Transition

Specific heat measurements show that the introduction of amorphous columnar defects considerably affects the transition from the normal to the superconducting state in zero magnetic field. Experimental results are compared to numerical simulations of the 3D XY model for both the pure system and the system containing random columnar disorder. The numerics reproduce the salient features of experiment, showing in particular that the specific heat peak changes from cusp-like to smoothly rounded when columnar defects are added. By considering the specific heat critical exponent alpha, we argue that such behavior is consistent with recent numerical work [Vestergren et al., PRB 70, 054508 (2004)] showing that the introduction of columnar defects changes the universality class of the transition.Comment: 4 pages, 2 figure

The Generic, Incommensurate Transition in the two-dimensional Boson Hubbard Model

The generic transition in the boson Hubbard model, occurring at an incommensurate chemical potential, is studied in the link-current representation using the recently developed directed geometrical worm algorithm. We find clear evidence for a multi-peak structure in the energy distribution for finite lattices, usually indicative of a first order phase transition. However, this multi-peak structure is shown to disappear in the thermodynamic limit revealing that the true phase transition is second order. These findings cast doubts over the conclusion drawn in a number of previous works considering the relevance of disorder at this transition.Comment: 13 pages, 10 figure

Rural Teaching Principal: Leadership with Precious Few Minutes

Presented is a case study of school leadership examining a rural teaching principal in a small K-12 school in a prairie province. The case examines the intensification of workload of a principal of a small K-12 school affected by reductions in student enrolment, staffing and administrative time. Overwhelmed by myriad responsibilities, the principal feels inadequate as both a teacher and a leader. She is exhausted in her efforts to provide quality learning and extracurricular opportunities for students as her workload continues to grow. Teaching activities examine the uniqueness of the teaching principal role and the ways in which leaders manage workload intensification in order to accomplish the responsibilities of this dual role