Lightweight engine containment

Kevlar fabric styles and weaves were studied, as well as methods of application for advanced gas turbine engines. The Kevlar material was subjected to high speed impacts by simple projectiles fired from a rifle, as well as more complex shapes such as fan blades released from gas turbine rotors in a spin pit. Just contained data was developed for a variety of weave and/or application techniques, and a comparative containment weight efficiency was established for Kevlar containment applications. The data generated during these tests is being incorporated into an analytical design system so that blade containment trade-off studies between Kevlar and metal case engine structures can be made. Laboratory tests and engine environment tests were performed to determine the survivability of Kevlar in a gas turbine environment

Oregon Mathematics Leadership Institute Project: Evaluation Results on Teacher Content Knowledge, Implementation Fidelity, and Student Achievement

The Oregon Mathematics Leadership Institute (OMLl) National Science Foundation Mathematics and Science Partnership project partners are Oregon State University, Portland State University, Teachers Development Group, and ten Oregon school districts. The primary activities of the project were a sequence of three intensive three-week residential institutes emphasizing mathematics content knowledge for teaching, collegial leadership, and the building of Professional Learning Communities. Teachers at all levels of grades K-12 participated together in the mathematics content courses. By the conclusion of the. third Summer Institute, teachers had shown significant improvements in mathematical content knowledge for teaching. Analysis of student achievement data in participating schools was initially inconclusive. However, once implementation fidelity traits were taken into account, a positive relationship between project participation and student achievement emerged. The degree to which schools implement the practices promoted by the OMLI project is a significant positive predictor of student perfomiance above and beyond what can be explained by the socioeconomic factor as indicated by the percentage of students who qualify for the free and reduced lunch program. This relationship is particularly acute at secondary levels, but additional factors appear to be at play at elementary grade levels

Spittlebug Control in Legumes

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X-ray Evidence for Multiple Absorbing Structures in Seyfert Galaxies

We have used X-ray spectra to measure attenuating columns in a large sample of Seyfert galaxies. Over 30 of these sources have resolved radio jets, allowing the relative orientation of the nucleus and host galaxy to be constrained. We have discovered that the distribution of absorbing columns is strongly correlated with the relative orientation of the Seyfert structures. This result is inconsistent with unification models including only a torus and is instead most readily explained if a second absorber is included: in addition to a Compton-thick, parsec-scale torus there would also be a larger-scale absorber with N_H < 10^{23} cm^{-2}. The second absorber is aligned with the host galactic plane while the torus is arbitrarily misaligned.Comment: 2 pages, 1 figure, to appear in "Multiwavelength AGN Surveys" (Cozumel, December 8-12 2003), ed. R. Maiolino and R. Mujica, Singapore: World Scientific, 2004. Additional material may be found at http://space.mit.edu/home/jonathan/research.htm

Everybody knows that the prisoner is going nowhere: Parole Board members’ views about dangerous and severe personality disorder in England and Wales

The Dangerous Severe Personality Disorder (DSPD) Programme has been a controversial initiative in England and Wales. First introduced in 1999, DSPD became a highly contested operational as opposed to diagnostic term, used to define a population convicted of violent offences who were admitted for treatment within one of four high security units established for men. The aim of this paper is to explore the outcomes of Parole Board (PB) reviews with DSPD prisoners and investigate PB members’ views about DSPD. Nearly all PB members observed that the high security location of the DSPD units was more influential to their decision-making than the label of DSPD. PB members highlighted their expectation that DSPD prisoners make a journey through different levels of security before release is an appropriate consideration. A key finding was that admission to DSPD services could be seen to have disrupted a prisoner’s progression and challenged PB members’ conceptions of the appropriate (and likely) future progression pathways available to prisoners. These findings have implications not only for the development of the new offender personality disorder pathway in England and Wales but also for other jurisdictions seeking to respond to the longstanding question of how to respond to high risk offenders with personality disorder

Scattering fidelity in elastodynamics

The recent introduction of the concept of scattering fidelity, causes us to revisit the experiment by Lobkis and Weaver [Phys. Rev. Lett. 90, 254302 (2003)]. There, the ``distortion'' of the coda of an acoustic signal is measured under temperature changes. This quantity is in fact the negative logarithm of scattering fidelity. We re-analyse their experimental data for two samples, and we find good agreement with random matrix predictions for the standard fidelity. Usually, one may expect such an agreement for chaotic systems only. While the first sample, may indeed be assumed chaotic, for the second sample, a perfect cuboid, such an agreement is more surprising. For the first sample, the random matrix analysis yields a perturbation strength compatible with semiclassical predictions. For the cuboid the measured perturbation strength is much larger than expected, but with the fitted values for this strength, the experimental data are well reproduced.Comment: 4 page