Integrated controls/structures study of advanced space systems

A cost tradeoff is postulated for a stiff structure utilizing minimal controls (and control expense) to point and stabilize the vehicle. Extra costs for a stiff structure are caused by weight, packaging size, etc. Likewise, a more flexible vehicle should result in reduced structural costs but increased costs associated with additional control hardware and data processing required for vibration control of the structure. This tradeoff occurs as the ratio of the control bandwidth required for the mission to the lowest (significant) bending mode of the vehicle. The cost of controlling a spacecraft for a specific mission and the same basic configuration but varying the flexibility is established

Classical {\it vs.}\ Landau-Ginzburg Geometry of Compactification

We consider superstring compactifications where both the classical description, in terms of a Calabi-Yau manifold, and also the quantum theory is known in terms of a Landau-Ginzburg orbifold model. In particular, we study (smooth) Calabi-Yau examples in which there are obstructions to parametrizing all of the complex structure cohomology by polynomial deformations thus requiring the analysis based on exact and spectral sequences. General arguments ensure that the Landau-Ginzburg chiral ring copes with such a situation by having a nontrivial contribution from twisted sectors. Beyond the expected final agreement between the mathematical and physical approaches, we find a direct correspondence between the analysis of each, thus giving a more complete mathematical understanding of twisted sectors. Furthermore, this approach shows that physical reasoning based upon spectral flow arguments for determining the spectrum of Landau-Ginzburg orbifold models finds direct mathematical justification in Koszul complex calculations and also that careful point- field analysis continues to recover suprisingly much of the stringy features.Comment: 14

Older people's experiences of changed medication appearance : a survey

This report details a survey of older people's experiences of changed medication appearance. The aims of the study were: • To develop a questionnaire in partnership with older people to survey older people’s views on fluctuating medication appearance • To elicit older people’s experiences of medication that changed appearance due to ‘generic prescribing’ and ‘parallel import’ practices and its impact on their medication taking practices. These common pharmacy practices mean that the same tablet medication can be issued to older people in different colours, sizes and shapes to their previous prescriptions. Older people from a local User/Carer Forum highlighted these problems to the research team and asked that we investigate to explore the extent of the problem. An eight-item questionnaire was developed and distributed to 2000 older people (50 years+) across participating PCTs in Greater Manchester in 2008. A 29% response rate was achieved. The data was analysed using the SPSS statistical package. Findings include: •63.3% experienced a change in the appearance of their tablet medications. •74.1% did not seek advice regarding the change in the appearance of their tablet medications. •Older people noted changes to the actual tablets, tablet packaging and written information that accompanies tablets. Changes are occurring to the colour, size and shape of tablets more than changes to packaging and written information. The majority of respondents had experienced changes in the appearance of their prescribed tablet medication in the previous two years which were not due to change in medication or dose etc. Worryingly, for some respondents, these changes prompted negative experiences such as anxiety, confusion and upset. Of particular concern was that a small number omitted the affected tablet medications and did not seek help or advice from GPs, pharmacists or relatives. Six older people have been study advisors from inception to dissemination of this study and significantly added to its quality. The study demonstrates substantive public engagement / user involvement in research. The findings suggest nurses and others have a role to play in promoting better medicines management and identifying those most at risk from changed appearance of medications

The study of excited oxygen molecule gas species production and quenching on thermal protection system materials

The detection of excited oxygen and ozone molecules formed by surface catalyzed oxygen atom recombination and reaction was investigated by laser induced fluorescence (LIF), molecular beam mass spectrometric (MBMS), and field ionization (FI) techniques. The experiment used partially dissociated oxygen flows from a microwave discharge at pressures in the range from 60 to 400 Pa or from an inductively coupled RF discharge at atmospheric pressure. The catalyst materials investigated were nickel and the reaction cured glass coating used for Space Shuttle reusable surface insulation tiles. Nonradiative loss processes for the laser excited states makes LIF detection of O2 difficult such that formation of excited oxygen molecules could not be detected in the flow from the microwave discharge or in the gaseous products of atom loss on nickel. MBMS experiments showed that ozone was a product of heterogeneous O atom loss on nickel and tile surfaces at low temperatures and that ozone is lost on these materials at elevated temperatures. FI was separately investigated as a method by which excited oxygen molecules may be conveniently detected. Partial O2 dissociation decreases the current produced by FI of the gas

Green's Functions and the Adiabatic Hyperspherical Method

We address the few-body problem using the adiabatic hyperspherical representation. A general form for the hyperangular Green's function in $d$-dimensions is derived. The resulting Lippmann-Schwinger equation is solved for the case of three-particles with s-wave zero-range interactions. Identical particle symmetry is incorporated in a general and intuitive way. Complete semi-analytic expressions for the nonadiabatic channel couplings are derived. Finally, a model to describe the atom-loss due to three-body recombination for a three-component fermi-gas of $^{6}$Li atoms is presented.Comment: 14 pages, 8 figures, 2 table