The nature of exhibits about acoustics in Science and Technology centres

This is a study of the opportunities currently provided by interactive science and technology centres for visitors' engagement in the field of acoustics. E-mails, requesting a description of exhibits on acoustics (sound and hearing) in use, were sent to members of staff of interactive science and technology centres around the world as well as to companies that design and sell exhibits. Eighty-seven descriptions of distinctive interactive exhibits were received and analysed. Results show that: there are few analogy-based exhibits concerning the more complex aspects of acoustics; narratives involving visitors' everyday lives, that might provide continuity between and beyond the situations presented by exhibits, are not generally provided; science is emphasised at the expense of technology; the risks, benefits and ethical implications of relevant technological artefacts are rarely mentioned; the majority of the exhibits are concerned with the fields of fundamental acoustics, hearing, and psychoacoustics. It is suggested that interactive science and technology centres need to rethink the design of exhibits about acoustics if their mission includes some appreciation of this important branch of science and technology.

Modelling the interdependence between the stoichiometry of receptor oligomerization and ligand binding for a coexisting dimer/tetramer receptor system

Many G protein-coupled receptors have been shown to exist as oligomers, but the oligomerization state and the effects of this on receptor function are unclear. For some G protein-coupled receptors, in ligand binding assays, different radioligands provide different maximal binding capacities. Here we have developed mathematical models for co-expressed dimeric and tetrameric species of receptors. We have considered models where the dimers and tetramers are in equilibrium and where they do not interconvert and we have also considered the potential influence of the ligands on the degree of oligomerization. By analogy with agonist efficacy, we have considered ligands that promote, inhibit or have no effect on oligomerization. Cell surface receptor expression and the intrinsic capacity of receptors to oligomerize are quantitative parameters of the equations. The models can account for differences in the maximal binding capacities of radioligands in different preparations of receptors and provide a conceptual framework for simulation and data fitting in complex oligomeric receptor situations.

Efficient shock capturing for isentropic flows using arithmetic averaging

A shock capturing scheme is presented for the equations of isentropic flow based on upwind differencing applied to a locally linearized set of Riemann problems. This includes the two-dimensional shallow water equations using the familiar gas dynamics analogy. An average of the flow variables across the interface between cells is required, and this average is chosen to be the arithmetic mean for computational efficiency, leading to arithmetic averaging. This is in contrast to usual ‘square root’ averages found in this type of Riemann solver where the computational expense can be prohibitive. The scheme is applied to a two-dimensional dam-break problem and the approximate solution compares well with those given by other authors.

An isentropic flow algorithm with body fitted meshes

An efficient algorithm based on flux difference splitting is presented for the solution of the three-dimensional equations of isentropic flow in a generalised coordinate system, and with a general convex gas law. The scheme is based on solving linearised Riemann problems approximately and in more than one dimension incorporates operator splitting. The algorithm requires only one function evaluation of the gas law in each computational cell. The scheme has good shock capturing properties and the advantage of using body-fitted meshes. Numerical results are shown for Mach 3 flow of air past a circular cylinder. Furthermore, the algorithm also applies to shallow water flows by employing the familiar gas dynamics analogy.

Extraction of Tschebysheff design data for the low pass dielectric multilayer

The extraction of design data for the lowpass dielectric multilayer according to Tschebysheff performance is described. The extraction proceeds initially by analogy with electric-circuit design, and can then be given numerical refinement which is also described. Agreement with the Tschebysheff desideratum is satisfactory. The multilayers extracted by this procedure are of fractional thickness, symmetric with regard to their central layers.

Photopolymerization of Pluronic F127 diacrylate: a colloid-templated polymerization

Pluronic F127 diacrylate (F127DA) is a bifunctional acrylate and as such it should in principle produce macroscopically cross-linked materials; however, its photopolymerization in water does not lead to 3D-extended hydrogels. The main species present after photopolymerization appear to be cross-linked micelles, which indicates that the micellar morphology of F127DA has a template effect on the polymerization. The structural analogy causes the physical state of precursor and polymerized materials to be very similar for a wide range of concentrations (5–25% wt) and temperatures (10–37 °C). Also the long-range morphology of F127DA appears to have a template effect: samples photopolymerized in a micellar gel state and redispersed at high concentration (25% wt) show a long-range organization that depended on the concentration and therefore on the order of the precursor.

Ontology supported competency system

Traditionally representation of competencies has been very difficult using computer-based techniques. This paper introduces competencies, how they are represented, and the related concept of competency frameworks and the difficulties in using traditional ontology techniques to formalise them. A “vaguely” formalised framework has been developed within the EU project TRACE and is presented. The framework can be used to represent different competencies and competency frameworks. Through a case study using an example from the IT sector, it is shown how these can be used by individuals and organisations to specify their individual competency needs. Furthermore it is described how these representations are used for comparisons between different specifications applying ontologies and ontology toolsets. The end result is a comparison that is not binary, but tertiary, providing “definite matches”, possible / partial matches, and “no matches” using a “traffic light” analogy.

Comovement in UK real estate sector returns

Engle et al. (1990) distinguish between 'heat waves' and 'meteor showers' in an analogy which tries to differentiate between particular effects, not transmitted among markets, and general effects, which tend to affect all the markets, although different markets can be affected to different degrees. This paper applies this approach to the study of the monthly returns of four real estate market sectors: Office, Retail, Industrial and Retail Warehouses in the UK over the period 1979:2 to 1997:12. A VAR methodology used with the aim of detecting the causal relations and dynamic interactions among sector returns, as well as the transmission mechanisms of their information flows. The results obtained permit us to conclude that there is a good deal of integration between the monthly return time series for all the sectors. Therefore, diversification across real estate market sectors does not allow for the reduction of risk without sacrificing expected returns.

Forward pricing and the housing market: the pre-sales housing system in Taiwan

In countries that have experienced rapid economic development, the need to establish more efficient markets in which private property can be constructed has induced some innovative solutions. One such solution is the phenomenon of a pre-sales market of the kind that can be observed in Taiwan, Korea, and more recently in China. Developers sell their property before building is started in order to acquire financing for the development companies. This paper discusses the process and, by recognising the analogy between the pre-sales market and forwards markets, analyses the implications for developers

“Ce n’est pas elle qu’on voit”: the photograph in the work of Annie Saumont

The incorporation of ekphrastic evocations of photographs into fictional works is a growing trend charted by (mostly) literary and (occasionally) art critics interested in the effect of their inclusion in a narrative. What has emerged as a veritable affinity of photography with literature has produced a fertile interdisciplinary critical discourse around areas of intersection between visual and verbal. With regard to short fiction, the photograph is often subject to investigation as analogy, the photograph and the short story being considered metonymically related with regard to form and effect. This notion of a structural equivalence between short story and photograph is one stressed by author/photographer Julio Cortàzar, concerned to highlight the quality of intensity he ascribes to both forms, which he saw as ‘cutting out a piece of reality’ in order to ‘breaking out’ into a wider one. Given Annie Saumont’s oft-cited admiration of Cortàzar’s work it is unsurprising that in her own writing – of stories themselves often classed, in their elliptical density, as verbal snapshots – she should take an interest in photographs and/or photographers. This article seeks to explore and analyse different values Saumont ascribes to what was paradoxically described by Barthes as ‘invisible’, in that what we see when viewing a photograph is, (often treacherously), ‘ pas elle qu’on voit’: never, or never solely, the actual object itself …

Cyclic extrusion of a lava dome based on a stick-slip mechanism

Lava dome eruptions are sometimes characterised by large periodic fluctuations in extrusion rate over periods of hours that may be accompanied by Vulcanian explosions and pyroclastic flows. We consider a simple system of nonlinear equations describing a 1D flow of lava extrusion through a deep elastic dyke feeding a shallower cylindrical conduit in order to simulate this short-period cyclicity. Stick-slip conditions depending on a critical shear stress are assumed at the wall boundary of the cylindrical conduit. By analogy with the behaviour of industrial polymers in a plastic extruder, the elastic dyke acts like a barrel and the shallower cylindrical portion of the conduit as a die for the flow of magma acting as a polymer. When we applied the model to the Soufrière Hills Volcano, Montserrat, for which the key parameters have been evaluated from previous studies, cyclic extrusions with periods from 3 to 30 h were readily simulated, matching observations. The model also reproduces the reduced period of cycles observed when a major unloading event occurs due to lava dome collapse.

Convective quasi–equilibrium

The concept of convective quasi–equilibrium (CQE) is a key ingredient in order to understand the role of deep moist convection in the atmosphere. It has been used as a guiding principle to develop almost all convective parameterizations and provides a basic theoretical framework for large–scale tropical dynamics. The CQE concept as originally proposed by Arakawa and Schubert [1974] is systematically reviewed from wider perspectives. Various interpretations and extensions of Arakawa and Schubert’s CQE are considered in terms of both a thermodynamic analogy and as a dynamical balance. The thermodynamic interpretations can be more emphatically embraced as a homeostasis. The dynamic balance interpretations can be best understood by analogy with the slow manifold. Various criticisms of CQE can be avoided by taking the dynamic balance interpretation. Possible limits of CQE are also discussed, including the importance of triggering in many convective situations, as well as the possible self–organized criticality of tropical convection. However, the most intriguing aspect of the CQE concept is that, in spite of many observational tests supporting and interpreting it in many different senses, it has 1never been established in a robust manner based on a systematic analysis of the cloud–work function budget by observations as was originally defined.

Serving two masters: a reflective narrative of reconciling the tensions faced in designing doctoral research

This paper presents a reflective narrative of the process of designing a PhD project. Using the analogy of the play 'One Man, Two Guvnors' , this paper discusses the tensions a beginning researcher faces in reconciling her own vision for a project with the academic demands of doctoral-level study. Focusing on an ethnographic study of a reading group for visually-impaired people, the paper explores how the researcher's developing understanding of the considerations necessary when working with disabled people impacted on the research design. In particular, it focuses on the conflict faced by doctoral students when working in a paradigm that requires actively involving research participants, thereby relinquishing some control over the project. The aim of the paper is to provide an honest narrative that will resonate with other beginning researchers.

Non-display uses of digital works: Google Books and beyond

With the advent of mass digitization projects, such as the Google Book Search, a peculiar shift has occurred in the way that copyright works are dealt with. Contrary to what has so far been the case, works are turned into machine-readable data to be automatically processed for various purposes without the expression of works being displayed to the public. In the Google Book Settlement Agreement, this new kind of usage is referred to as ‘non-display uses’ of digital works. The legitimacy of these uses has not yet been tested by Courts and does not comfortably fit in the current copyright doctrine, plainly because the works are not used as works but as something else, namely as data. Since non-display uses may prove to be a very lucrative market in the near future, with the potential to affect the way people use copyright works, we examine non-display uses under the prism of copyright principles to determine the boundaries of their legitimacy. Through this examination, we provide a categorization of the activities carried out under the heading of ‘non-display uses’, we examine their lawfulness under the current copyright doctrine and approach the phenomenon from the spectrum of data protection law that could apply, by analogy, to the use of copyright works as processable data.