11,771 research outputs found
Exceptional SW Geometry from ALE Fibrations
We show that the genus 34 Seiberg-Witten curve underlying Yang-Mills
theory with gauge group yields physically equivalent results to the
manifold obtained by fibration of the ALE singularity. This reconciles a
puzzle raised by string duality
The Refined Elliptic Genus and Coulomb Gas Formulations of Superconformal Coset Models
We describe, in some detail, a number of different Coulomb gas formulations
of superconformal coset models. We also give the mappings between these
formulations. The ultimate purpose of this is to show how the Landau-Ginzburg
structure of these models can be used to extract the -generators, and to
show how the computation of the elliptic genus can be refined so as to extract
very detailed information about the characters of component parts of the model.Comment: 40 pages in harvmac, no figure
Approach trajectory planning system for maximum concealment
A computer-simulation study was undertaken to investigate a maximum concealment guidance technique (pop-up maneuver), which military aircraft may use to capture a glide path from masked, low-altitude flight typical of terrain following/terrain avoidance flight enroute. The guidance system applied to this problem is the Fuel Conservative Guidance System. Previous studies using this system have concentrated on the saving of fuel in basically conventional land and ship-based operations. Because this system is based on energy-management concepts, it also has direct application to the pop-up approach which exploits aircraft performance. Although the algorithm was initially designed to reduce fuel consumption, the commanded deceleration is at its upper limit during the pop-up and, therefore, is a good approximation of a minimum-time solution. Using the model of a powered-lift aircraft, the results of the study demonstrated that guidance commands generated by the system are well within the capability of an automatic flight-control system. Results for several initial approach conditions are presented
MLS vertical guidance and navigation for a STOL airplane landing on an elevated STOLport
In contrast to CTOL landing operations, STOL airplanes landing on short STOLport runways typically begin the flare maneuver before reaching the runway surface. Vertical guidance procedures were developed to allow an autoland flight control system for a STOL airplane to use Microwave Landing System (MLS) signals as altitude and sink rate references for flare initiation, with a transition to radar altimeter after the airplane is over the runway. The implementation has minimum impact on the control system and landing performance. Data are presented which show validation of the concepts in a simulator
Excluded Girls’ Stories of Belonging
Exclusion from school is an issue of national and local concern. With more boys experiencing exclusion than girls the research is dominated by a male perspective. This research aimed to provide an in-depth exploration of the experience of girls who have been excluded and are currently attending Alternative Provisions (AP). A sense of belonging is linked to more positive outcomes therefore this research was underpinned by an exploration of the belonging these girls have experienced in their previous and current settings along with their hopes for the future.
This exploratory research had a constructivist epistemology and an ontological position of relativism. It accepts that multiple realities are constructed through lived experience and individually constructed and focuses on the stories of three secondary age girls. The research took a narrative approach and a guided interview and life grids were used to support the gathering of data remotely. Participants’ narratives were re-storied according to Clandinin and Connelly’s (2000) threedimensional space, offering rich and detailed insights into the complexity of their experiences. In the second phase of analysis, the three storied narratives were analysed using narrative thematic analysis, and several themes and subthemes were identified for each of the research questions.
The girls were found to experience higher levels of belonging in their alternative provision, feeling a lack of autonomy in their mainstream experiences. Positive teacher relationships contained the most powerful narratives. The girls found in the alternative provisions that male students can experience increased support from staff and that more resources were directed towards their experiences. The girls outlined hopes and aspirations for the future, but these were limited by a fear of a repeated experience of a lack of understanding around their needs. The implications of the research findings for both national strategy, Educational Psychology practice and Educational settings are discussed
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