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Smart biomimetic construction materials for next generation infrastructure
The resilience of building and civil engineering structures is typically associated with the design of individual elements such that they have sufficient capacity or potential to react in an appropriate manner to adverse events. Traditionally this has been achieved by using ârobustâ design procedures that focus on defining safety factors for individual adverse events and providing redundancy. As such, construction materials are designed to meet a prescribed specification; material degradation is viewed as inevitable and mitigation necessitates expensive maintenance regimes; ~ÂŁ40 billion/year is spent in the UK on repair and maintenance of existing, mainly concrete, structures. More recently, based on a better understanding and knowledge of microbiological systems, materials that have the ability to adapt and respond to their environment have been developed. This fundamental change has the potential to facilitate the creation of a wide range of âsmartâ materials and intelligent structures, including both autogenous and autonomic selfâhealing materials and adaptable, selfâsensing and selfârepairing structures, which can transform our infrastructure by embedding resilience in the materials and components of these structures so that rather than being defined by individual events, they can evolve over their lifespan. We therefore advocate that next generation infrastructure will include next generation infrastructure materials based on smart biomimetic construction materials. This paper presents details of the national consortium that is leading international efforts in the development of those next generation infrastructure materials. It presents details of the work done to date, over the past three years, as part of the EPSRC funded project Materials for Life and the plans for work to be done over the next five years as part of a follow-on Programme grant: Resilient Materials for Life
Linear or Rotary Actuator Using Electromagnetic Driven Hammer as Prime Mover
We claim a hammer driven actuator that uses the fast-motion, low-force characteristics of an electro-magnetic or similar prime mover to develop kinetic energy that can be transformed via a friction interface to produce a higher-force, lower-speed linear or rotary actuator by using a hammering process to produce a series of individual steps. Such a system can be implemented using a voice-coil, electro-mechanical solenoid or similar prime mover. Where a typical actuator provides limited range of motion or low force, the range of motion of a linear or rotary impact driven motor can be configured to provide large displacements which are not limited by the characteristic dimensions of the prime mover
Human rights and public education
This article attempts a contrast to the contribution by Hugh Starkey. Rather than his account of the inexorable rise of human rights discourse, and of the implementation of human rights standards, human rights are here presented as always and necessarily scandalous and highly contested. First, I explain why the UK has lagged so far behind its European neighbours in implementing citizenship education. Second, a comparison with France shows that the latest UK reforms bring us up to 1789. Third, the twentieth-century second-generation social and economic rights are still anathema in the UK. Fourth, the failure to come to terms with Empire and especially the slave trade means that the UKâs attitude to third-generation rights, especially the right of peoples to self-determination, is heavily compromised. Taking into account the points I raise, citizenship education in the UK might look very different
Preliminary performance measurements of bolometers for the Planck high-frequency instrument
We report on the characterization of bolometers fabricated at the Jet Propulsion Laboratory for the High Frequency Instrument (HFI) of the joint ESA/NASA Herschel/Planck mission to be launched in 2007. The HFI is a multicolor focal plane which consists of 48 bolometers operated at 100mK. Each bolometer is mounted to a feedhorn-filter assembly which defines one of six frequency bands centered between 100-857GHz. Four detectors in each of six bands are coupled to both linear polarizations and thus measure the total intensity. In addition, eight detectors in each of 3 bands (143, 217, and 353GHz) couple only to a single linear polarization and thus provide measurements of the Stokes parameters, Q and U, as well the total intensity. The detectors are required to achieve a Noise Equivalent Power (NEP) at or below the background limit ⌠10^(-17)W/âHz for the telescope and time constants of a few ms, short enough to resolve point sources as the 5 to 9 arc-minute beams move across the sky in great circles at 1 rpm. The bolometers are tested at 100mK in a commercial dilution refrigerator with a custom built thermal control system to regulate the heat sink with precision < 100nK/âHz. The 100mK tests include dark electrical characterization of the load curves, optical and electrical measurement of the thermal time constants and measurement of the noise spectral density from 0.01 to 10Hz for up to 24 bolometers simultaneously
Analytical solution of a model for complex food webs
We investigate numerically and analytically a recently proposed model for
food webs [Nature {\bf 404}, 180 (2000)] in the limit of large web sizes and
sparse interaction matrices. We obtain analytical expressions for several
quantities with ecological interest, in particular the probability
distributions for the number of prey and the number of predators. We find that
these distributions have fast-decaying exponential and Gaussian tails,
respectively. We also find that our analytical expressions are robust to
changes in the details of the model.Comment: 4 pages (RevTeX). Final versio
Population Uncertainty in Model Ecosystem: Analysis by Stochastic Differential Equation
Perturbation experiments are carried out by contact process and its
mean-field version. Here, the mortality rate is increased or decreased
suddenly. It is known that the fluctuation enhancement (FE) occurs after the
perturbation, where FE means a population uncertainty. In the present paper, we
develop a new theory of stochastic differential equation. The agreement between
the theory and the mean-field simulation is almost perfect. This theory enables
us to find much stronger FE than reported previously. We discuss the population
uncertainty in the recovering process of endangered species.Comment: 16 pages, 4 figure, submitted to J. Phys. Soc. Jp
Ethical and compliance-competence evaluation: a key element of sound corporate governance
Motivated by the ongoing post-Enron refocusing on corporate governance and the shift by the Financial Services Authority (FSA) in the UK to promoting compliance- competence within the financial services sector, this paper demonstrates how template analysis can be used as a tool for evaluating compliance-competence. Focusing on the ethical dimension of compliance-competence, we illustrate how this can be subjectively appraised. We propose that this evaluation technique could be utilised as a starting point in informing senior management of corporate governance issues and be used to monitor and demonstrate key compliance and ethical aspects of an institution to external stakeholders and regulators
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