On the isomorphism between the reduction algebra and the invariant differential operators on Lie groups

Using techniques of deformation (bi)quantization we establish a non-canonical algebra isomorphism between the deformed reduction algebra and the invariant differential operators on G/H. Further results concerning other deformations of these two algebras are also proved. Part of the author's PhD thesis at University Paris 7, 2009.Comment: 27 page

Variability Abstraction and Refinement for Game-Based Lifted Model Checking of Full CTL

One of the most promising approaches to fighting the configuration space explosion problem in lifted model checking are variability abstractions. In this work, we define a novel game-based approach for variability-specific abstraction and refinement for lifted model checking of the full CTL, interpreted over 3-valued semantics. We propose a direct algorithm for solving a 3-valued (abstract) lifted model checking game. In case the result of model checking an abstract variability model is indefinite, we suggest a new notion of refinement, which eliminates indefinite results. This provides an iterative incremental variability-specific abstraction and refinement framework, where refinement is applied only where indefinite results exist and definite results from previous iterations are reused. The practicality of this approach is demonstrated on several variability models

Seeing clearly – the redevelopment of the Central Library, Imperial College London: a review of the extension and refurbishment of the Central Library, South Kensington campus, from concept to completion and beyond

A review of the redevelopment of Level one of the Central Library, Imperial College LondonPublished versio

Performance of EcoSan Toilets at Majumbasita in Dar Es Salaam – Tanzania

The performance of Ecological Sanitation (ECOSAN) toilets at Majumbasita-Ukonga in Dar es Salaam, Tanzania was studied in order to assess their feasibility for low cost and effective environmental protection. The studied parameters for urine were pH, TKN, phosphorus , potassium and E-coli and for faecal sludge were temperature, pH, TS, VS, COD , TKN, ammonium, phosphorus, potassium and Ascaris eggs. Results indicated a high pH up to 10.3 in the faecal contents due to addition of ashes. The temperatures were between 270C – 31.70C during the whole study period. The total COD measurements varied from 33 - 74 gCOD/l, while TS and VS were respectively 57– 81 gTS/l and 21 – 46 gVS/l. The results for TKN, ammonium, phosphorus and potassium in faecal sludge were 5045 – 6080mg/L, 5207-5852 mg/L, 29-70mg/L and 105-176 mg/L, respectively. Ascaris eggs were efficiently removed from faecal sludge that were strictly dry and had a pH of more than 10. The results for TKN, ammonium, phosphorus and potassium in urine were 4285-5010 mg/L, 111-195 mg/L and 190-251 mg/L, respectively. E-Coli were present in urine with pH less than 11.5 and were efficiently removed from urine with pH more than 11.5. Presence of pathogens in urine implies the separated urine can be reused in tree growing and not for fertilising food crops consumed raw

Laser-assisted bumping for flip chip assembly

Published versio

ON INTERACTION BETWEEN FALLING BODIES AND THE SURROUNDING FLUID

Interactions between a finite number of bodies and the surrounding fluid, in a channel for instance, are investigated theoretically. In the planar model here the bodies or modelled grains are thin solid bodies free to move in a nearly parallel formation within a quasi-inviscid fluid. The investigation involves numerical and analytical studies and comparisons. The three main features that appear are a linear instability about a state of uniform motion, a clashing of the bodies (or of a body with a side wall) within a finite scaled time when nonlinear interaction takes effect, and a continuum-limit description of the body–fluid interaction holding for the case of many bodies

Thermosonic flip chip interconnection using electroplated copper column arrays

Published versio

User characteristics: Professional vs. lay users

(User characteristics: professional use vs lay use by Cifter A and Dong H) The market success of a product largely depends on whether it correctly addresses the user needs. Understanding the user is increasingly becoming important in the design process. Different user models may determine different approaches to design. This paper identifies the characteristics of different types of users, with a specific focus on professional users and lay users. It gives a definition of professional users and lay users in the context of adapting products originally designed for professional use to the use of lay people (for example, home use medical devices). It summarises, and compares, the characteristics of professional users and lay users, suggesting that designers pay attention to user characteristics and the context of use so as to better address user perceptions and meet user needs

Kinetics of phloretin binding to phosphatidylcholine vesicle membranes.

The submillisecond kinetics for phloretin binding to unilamellar phosphatidylcholine (PC) vesicles was investigated using the temperature-jump technique. Spectrophotometric studies of the equilibrium binding performed at 328 nm demonstrated that phloretin binds to a single set of independent, equivalent sites on the vesicle with a dissociation constant of 8.0 microM and a lipid/site ratio of 4.0. The temperature of the phloretin-vesicle solution was jumped by 4 degrees C within 4 microseconds producing a monoexponential, concentration-dependent relaxation process with time constants in the 30--200-microseconds time range. An analysis of the concentration dependence of relaxation time constants at pH 7.30 and 24 degrees C yielded a binding rate constant of 2.7 X 10(8) M-1 s-1 and an unbinding constant of 2,900 s-1; approximately 66 percent of total binding sites are exposed at the outer vesicle surface. The value of the binding rate constant and three additional observations suggest that the binding kinetics are diffusion limited. The phloretin analogue, naringenin, which has a diffusion coefficient similar to phloretin yet a dissociation constant equal to 24 microM, bound to PC vesicle with the same rate constant as phloretin did. In addition, the phloretin-PC system was studied in buffers made one to six times more viscous than water by addition of sucrose or glycerol to the differ. The equilibrium affinity for phloretin binding to PC vesicles is independent of viscosity, yet the binding rate constant decreases with the expected dependence (kappa binding alpha 1/viscosity) for diffusion-limited processes. Thus, the binding rate constant is not altered by differences in binding affinity, yet depends upon the diffusion coefficient in buffer. Finally, studies of the pH dependence of the binding rate constant showed a dependence (kappa binding alpha [1 + 10pH-pK]) consistent with the diffusion-limited binding of a weak acid