Modeling Frequency-Dependent Boundaries as Digital Impedance Filters in FDTD and K-DWM Room Acoustics Simulations

A new method for modeling-frequency-dependent boundaries in finite-difference time-domain (FDTD) and Kirchhoff variable digital waveguide mesh (K-DWM) room acoustics simulations is presented. The proposed approach allows the direct incorporation of a digital impedance filter (DIF) in the Multidimensional (2D or 3D) FDTD boundary model of a locally reacting surface. An explicit boundary update equation is obtained by carefully constructing a Suitable recursive formulation. The method is analyzed in terms of pressure wave reflectance for different wall impedance filters and angles of incidence. Results obtained from numerical experiments confirm the high accuracy of the proposed digital impedance filter boundary model, the reflectance of which matches locally reacting surface (LRS) theory closely. Furthermore a numerical boundary analysis (NBA) formula is provided as a technique for an analytic evaluation of the numerical reflectance of the proposed digital impedance filter boundary formulation.

Dilemmatic human-animal boundaries in Britain and Romania: Post-materialist and materialist dehumanization

Theories of dehumanization generally assume a single clear-cut, value-free and non-dilemmatic boundary between the categories 'human' and 'animal'. The present study highlights the relevance of dilemmas involved in drawing that boundary. In six focus groups carried out in Romania and Britain, 42 participants were challenged to think about dilemmas pertaining to animal and human life. Four themes were identified: rational autonomy, sentience, speciesism and maintaining materialist and post-materialist values. Sentience made animals resemble humans, while humans' rational autonomy made them distinctive. Speciesism underlay the human participants' prioritization of their own interests over those of animals, and a conservative consensus that the existing social system could not change supported this speciesism when it was challenged. Romanian participants appealed to Romania's lack of modernity and British participants to Britain's modernity to justify such conservatism. The findings suggest that the human-animal boundary is not essentialized; rather it seems that such boundary is constructed in a dilemmatic and post hoc way. Implications for theories of dehumanization are discussed.

Cold War Along the Emerald Curtain: Rural Boundaries in a Contested Border Zone

This paper examines how anxieties about ethnic identity proliferate as state borders begin to shift and open in response to accelerating possibilities of cross-border cooperation. As the border becomes more porous, social and cultural boundaries become marked in other ways, spatially re-scaled to reflect new uncertainties consequent upon border change. Using an example from the Irish land border, the paper traces how national space is re-imagined and re-placed in the everyday practices of residents in a violent border zone from which the state is ostensibly retreating. It shows that communal division is as sharply drawn as ever at a time when the ‘visibility’ of the state border itself is beginning to diminish.

Reducing Uncertainty in Aeroelastic Flutter Boundaries Using Experimental Data

Flutter prediction as currently practiced is usually deterministic, with a single structural model used to represent an aircraft. By using interval analysis to take into account structural variability, recent work has demonstrated that small changes in the structure can lead to very large changes in the altitude at which
utter occurs (Marques, Badcock, et al., J. Aircraft, 2010). In this follow-up work we examine the same phenomenon using probabilistic collocation (PC), an uncertainty quantification technique which can eficiently propagate multivariate stochastic input through a simulation code,
in this case an eigenvalue-based fluid-structure stability code. The resulting analysis predicts the consequences of an uncertain structure on incidence of
utter in probabilistic terms { information that could be useful in planning
flight-tests and assessing the risk of structural failure. The uncertainty in
utter altitude is confirmed to be substantial. Assuming that the structural uncertainty represents a epistemic uncertainty regarding the
structure, it may be reduced with the availability of additional information { for example aeroelastic response data from a flight-test. Such data is used to update the structural uncertainty using Bayes' theorem. The consequent
utter uncertainty is significantly reduced across the entire Mach number range.

THE DISTRIBUTION AND POPULATION REGULATION OF THE WOOD MOUSE APODEMUS-SYLVATICUS ON FIELD BOUNDARIES OF PASTORAL FARMLAND

1. The population characteristics and distribution of wood mice Apodemus sylvaticus (L.) were investigated along field margins of farmland dominated by grass production. 2. Turnover, sex ratio, breeding season, spatial density dependence and density dependence in reproductive activity indicated that the population ecology of A. sylvaticus is consistent in different habitats in the same geographical region. 3. Spatial variation in the abundance of A.sylvaticus was related negatively to percentage of land under pasture and distance from woodland and positively related to variables associated with food supply and cover. 4. Variation in numbers of overwintered mice at the start of the breeding season was related more closely to breeding opportunity than to environmental factors. This was particularly so in males. 5. The association of overwintered male and female A. sylvaticus remained evident in the later half of the breeding season. Young males and females of the year, however, were distributed more with respect to physical and biological features than towards adults or reproductive opportunity. 6. A. sylvaticus is an important species of field margins, even where these are poorly developed and agriculture is pastoral rather than arable. Further studies of this species in a wider range of agricultural systems are desirable.

Working across boundaries to improve health outcomes: a case study of a housing support and outreach service for homeless people living with HIV

This paper reports the findings of an evaluation of the ‘Housing Support, Outreach and Referral’ service developed to support people living with HIV who were homeless or at risk of homelessness. The service was set up as part of the Supporting People Health Pilot programme established to demonstrate the policy links between housing support services and health and social care services by encouraging the development of integrated services. The paper considers the role of housing support in improving people's health, and considers the challenges of working across housing, health and social care boundaries. The evaluation of the health pilot employed two main sources of data collection: quarterly project evaluation reports, which collected process data as well as reporting progress against aims and objectives, and semi-structured interviews with professionals from all key stakeholder groups and agencies, and with people who used services. Over the course of 15 months, 56 referrals were received of which 27 were accepted. Fifteen people received tenancy support of whom 12 were helped to access temporary accommodation. At the end of the 15 months, all of the tenancies had been maintained. In addition, 18 people registered with a general practitioner and 13 registered with an HIV clinic. Interviews with professionals emphasised the importance of the local joint working context, the involvement of the voluntary sector and the role of the support workers as factors that accounted for these outcomes. Those using services placed most emphasis on the flexibility of the support worker role. Importantly, interviews with professionals and those using services suggest that the role of support worker incorporates two dimensions – those of networker/navigator as well as advocate – and that both dimensions are important in determining the effectiveness of the service.