Morphing of ‘flying’ shapes for autonomous underwater and aerial vehicles

Autonomous vehicles are energy poor and should be designed to minimise the power required to propel them throughout their mission. The University of Southampton’s School of Engineering Sciences is actively involved in the development of improved designs for aerial and maritime autonomous vehicles. The ability to adapt or ‘morph’ their shape in-flight offers an opportunity to extend mission range/duration and improve agility. The practical implementation of such systems at small scale requires detailed consideration of the number, mass and power requirements of the individual actuation elements. Three approaches for minimising actuation requirements are considered. The first uses a combination of push-pull actuators coupled with a snap-through composite lay-up to achieve alterations in shape. It is proposed that such a system could be applied to the trailing edge of an autonomous underwater glider wing instead of the more usual servo operated trailing edge flap. The anisotropy achieved through use of different composite ply orientations and stacking can also be used to generate bend-twist coupling such that fluid dynamic loads induce ‘passive’ shape adaptation. The third approach uses a detailed understanding of the structural response of buckled elements to applied control moments to deform a complete wing. At this stage of the research no definitive conclusions have been drawn other than that all three approaches show sufficient promise and can now be applied to one of the autonomous vehicles

Law Schools as Knowledge Centers in the Digital Age

This article explores what it would mean for law schools to be “knowledge centers” in the digital age, and to have this as a central mission. It describes the activities of legal knowledge centers as: (1) focusing on solving real legal problems in society outside of the academy; (2) evaluating the problem-solving effectiveness of the legal knowledge being developed; (3) re-conceptualizing the structures used to represent legal knowledge, the processes through which legal knowledge is created, and the methods used to apply that knowledge; and (4) disseminating legal knowledge in ways that assist its implementation. The Article uses as extended examples of knowledge centers in the digital age the research laboratories in the sciences, and in particular research laboratories in linguistics and information science. It uses numerous examples to suggest how law schools might implement the concept of a knowledge center

Law Schools as Knowledge Centers in the Digital Age

This article explores what it would mean for law schools to be “knowledge centers” in the digital age, and to have this as a central mission. It describes the activities of legal knowledge centers as: (1) focusing on solving real legal problems in society outside of the academy; (2) evaluating the problem-solving effectiveness of the legal knowledge being developed; (3) re-conceptualizing the structures used to represent legal knowledge, the processes through which legal knowledge is created, and the methods used to apply that knowledge; and (4) disseminating legal knowledge in ways that assist its implementation. The Article uses as extended examples of knowledge centers in the digital age the research laboratories in the sciences, and in particular research laboratories in linguistics and information science. It uses numerous examples to suggest how law schools might implement the concept of a knowledge center

Social Impact

From the Dean: Remember the Past. Imagine the Future. Celebrate Today.; Perspectives: Temperature Rising: Health Care Reform is Back; Bookshelf: From Incentives to Intuition: What Faculty and Staff are Reading.; Perspectives with Melissa Jonson-Reid & Brett Drake: Changing the Role of Child Welfare; Perspectives: SEED for Oklahoma Kids.; Interview: Q&A with Julian Le Grand; Connecting Individual Health with Public Health: New interdisciplinary approaches are needed to solve today\u27s health care challenges. The solution lies at the nexus of social work, public health, and medicine.; The Green Dream: The social work profession has been slow to engage the issue of environmental justice, but a student-led initiative may spark new interest.; Serving Soldiers: The needs of returning veterans have changed, which has opened opportunities for new collaborations between schools of social work and the Department of Veterans Affairs.; Notebook: Research: Examining and identifying barriers to type 2 diabetes management among adolescents, key to reducing risk of complications; Notebook: Research: Study shows autism symptoms can improve into adulthood.; Notebook: Faculty News; Notebook: Events; Celebrate Our Histor

Implications of the Top Quark Mass Measurement for the CKM Parameters, xsx_s and CP Asymmetries

Motivated by the recent determination of the top quark mass by the CDF collaboration, \mt =174 \pm 10 ^{+13}_{-12} GeV, we review and update the constraints on the parameters of the quark flavour mixing matrix $V_{CKM}$ in the standard model. In performing our fits, we use inputs from the measurements of the following quantities: (i) \abseps, the CP-violating parameter in $K$ decays, (ii) \delmd, the mass difference due to the \bdbdbar\ mixing, (iii) the matrix elements \absvcb and \absvub, and (iv) $B$-hadron lifetimes. We find that the allowed region of the unitarity triangle is very large, mostly due to theoretical uncertainties. (This emphasizes the importance of measurements of CP-violating rate asymmetries in the $B$ system.) Nevertheless, the present data do somewhat restrict the allowed values of the coupling constant product $f_{B_d}\sqrt{\hat{B}_{B_d}}$ and the renormalization-scale invariant bag constant $\hat{B}_K$. With the updated CKM matrix we present the currently-allowed range of the ratio $\vert V_{td}/V_{ts} \vert$, as well as the standard model predictions for the \bsbsbar\ mixing parameter \xs and the quantities $\sin 2\alpha$, $\sin 2\beta$ and $\sin^2\gamma$, which characterize the CP-asymmetries in $B$-decays. The ALEPH collaboration has recently reported a significant improvement on the lower limit on the \bs-\bsb mass difference, $\Delta M_s/\Delta M_d > 11.3$ (95\% C.L.). This has interesting consequences for the CKM parameters which are also worked out. NOTE: this is a revised and updated version of our previous paper.Comment: LaTeX, 27 pages, 16 uuencoded figures (enclosed), CERN-TH.7398/94, UdeM-GPP-TH-94-0

Social Impact

From the Dean: Our Work in this Economy.; Interview: Q&A with Paul C. Brophy; Bookshelf: Understanding Assets: Two new books explore the impact of ownership and assets on individuals and communities; Perspectives with Matthew Kreuter: Communication Connections; Building a New Paradigm: Transdisciplinary Research Comes to the Forefront; A Sense of Place: Place-Based Initiatives Help Communities and Students; Notebook: Research: Tutoring Produces Big Gains in Student Learning; Notebook: Research: Free Exercise and Nutrition Program in Brazil Could Serve as Model in United States; Notebook: Research: Growing Problem for Veterans-Domestic Violence; Notebook: Message of Service Drives Surge in Peace Corps Applications; Notebook: Research: Black Newspapers Used as Cancer Education Tool in African American Communities; Notebook: Partnerships: Indian Immersion: 22-day Exchange Offers Insight into Mental Health and Poverty; Notebook: New on the Web: Creating Community: New Online Resources; Notebook: Faculty News; Alumni News and Note

Non-negative mixed finite element formulations for a tensorial diffusion equation

We consider the tensorial diffusion equation, and address the discrete maximum-minimum principle of mixed finite element formulations. In particular, we address non-negative solutions (which is a special case of the maximum-minimum principle) of mixed finite element formulations. The discrete maximum-minimum principle is the discrete version of the maximum-minimum principle. In this paper we present two non-negative mixed finite element formulations for tensorial diffusion equations based on constrained optimization techniques (in particular, quadratic programming). These proposed mixed formulations produce non-negative numerical solutions on arbitrary meshes for low-order (i.e., linear, bilinear and trilinear) finite elements. The first formulation is based on the Raviart-Thomas spaces, and is obtained by adding a non-negative constraint to the variational statement of the Raviart-Thomas formulation. The second non-negative formulation based on the variational multiscale formulation. For the former formulation we comment on the affect of adding the non-negative constraint on the local mass balance property of the Raviart-Thomas formulation. We also study the performance of the active set strategy for solving the resulting constrained optimization problems. The overall performance of the proposed formulation is illustrated on three canonical test problems.Comment: 40 pages using amsart style file, and 15 figure

Testing factorization in B -> D(*)X decays

In QCD the amplitude for B0 -> D(*)+pi- factorizes in the large Nc limit or in the large energy limit Q >> Lambda_QCD where Q = {m_b, m_c, m_b-m_c}. Data also suggests factorization in exclusive processes B-> D* pi+ pi- pi- pi0 and B-> D* omega pi-, however by themselves neither large Nc nor large Q can account for this. Noting that the condition for large energy release in B0-> D+ pi- is enforced by the SV limit, m_b, m_c >> m_b-m_c >> Lambda, we propose that the combined large Nc and SV limits justify factorization in B -> D(*) X. This combined limit is tested with the inclusive decay spectrum measured by CLEO. We also give exact large Nc relations among isospin amplitudes for B -> D(*)X and B -> D(*) D-bar(*)X, which can be used to test factorization through exclusive or inclusive measurements. Predictions for the modes B-> D(*) pi pi, B-> D(*)K K-bar and B-> D(*) D-bar(*) K are discussed using available data.Comment: 15 pages, 3 included .eps figures, minor change

Focused very high-energy electron beams as a novel radiotherapy modality for producing high-dose volumetric elements

The increased inertia of very high-energy electrons (VHEEs) due to relativistic effects reduces scattering and enables irradiation of deep-seated tumours. However, entrance and exit doses are high for collimated or diverging beams. Here, we perform a study based on Monte Carlo simulations of focused VHEE beams in a water phantom, showing that dose can be concentrated into a small, well-defined volumetric element, which can be shaped or scanned to treat deep-seated tumours. The dose to surrounding tissue is distributed over a larger volume, which reduces peak surface and exit doses for a single beam by more than one order of magnitude compared with a collimated beam

Evading the CKM Hierarchy: Intrinsic Charm in B Decays

We show that the presence of intrinsic charm in the hadrons' light-cone wave functions, even at a few percent level, provides new, competitive decay mechanisms for B decays which are nominally CKM-suppressed. For example, the weak decays of the B-meson to two-body exclusive states consisting of strange plus light hadrons, such as B\to\pi K, are expected to be dominated by penguin contributions since the tree-level b\to s u\bar u decay is CKM suppressed. However, higher Fock states in the B wave function containing charm quark pairs can mediate the decay via a CKM-favored b\to s c\bar c tree-level transition. Such intrinsic charm contributions can be phenomenologically significant. Since they mimic the amplitude structure of ``charming'' penguin contributions, charming penguins need not be penguins at all.Comment: 28 pages, 6 figures, published version. References added, minor change