2,415 research outputs found

    Field measurement of penetrator seismic coupling in sediments and volcanic rocks

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    Field experiments were conducted to determine experimentally how well a seismometer installed using a penetrator would be coupled to the ground. A dry lake bed and a lava bed were chosen as test sites to represent geological environments of two widely different material properties. At each site, two half-scale penetrators were fired into the ground, a three-component geophone assembly was mounted to the aft end of each penetrator, and dummy penetrators were fired at various distances to generate seismic signals. The recorded signals were digitized, and cross-spectral analyses were performed to compare the observed signals in terms of power spectral density ratio, coherence and phase difference. The analyses indicate that seismometers deployed by penetrators will be as well coupled to the ground as are seismometers installed by conventional methods for the frequency range of interest in earthquake seismology, although some minor differences were observed at frequencies near the upper limit of the frequency band

    Supporting memory and identity in older people: findings from a ā€˜Sandpitā€™ process

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    Identity in old age is challenged by physical changes, evolving roles within the family, and life transitions such as retirement. Supporting identity is therefore important in later life, and might be assisted by media technologies which allow people to reflect on their lives, record their personal histories and share these with family, friends and caregivers. This possibility was explored in two creative ā€˜Sandpitsā€™ with older people as part of the SUS-IT project, funded by the New Dynamics of Ageing programme in the UK. Discussions were held with PC and non-PC user groups of retirement age to understand memory and identity practices and elicit reactions to three novel product concepts. These included a Reminiscing Radio for life review, a Story Lamp for associating spoken stories with photographs and memorabilia, and a pair of virtual reality Travel Glasses for transporting you back to a special place in the past. The main findings of these discussions will be presented, along with concepts generated by the participants in a re-design exercise. This paper will also show how the sandpits enabled older people to be involved in the design process by allowing them to shape early design concepts through exploring their own ideas and motivations

    Field Measurements of Penetrator Seismic Coupling in Sediments and Volcanic Rocks

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    Field experiments were conducted to determine how well a seismometer installed using a penetrator would be coupled to the ground. A dry-lake bed and a lava bed were chosen as test sites to represent geological environments of two widely different material properties. At each site, two half-scale penetrators were fired into the ground, a three-component geophone assembly was mounted to the aft end of each penetrator, and dummy penetrators were at various distances to generate seismic signals. These signals were detected by the penetrator-mounted geophone assembly and by a reference geophone assembly buried or anchored to surface rock and 1-m from the penetrator. The recorded signals were digitized, and cross-spectral analyses were performed to compare the observed signals in terms of power spectral density ratio, coherence, and phase difference. The analyses indicate that seismometers deployed by penetrators will be as well coupled to the ground as are seismometers installed by conventional methods for the frequency range of interest in earthquake seismology

    Holidaying with the family pet: No dogs allowed!

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    This paper assesses the extent to which dog owners located in Brisbane, Australia, wish to holiday with their pets, and whether there is a gap between this desire and reality. The paper also examines the extent to which this demand is being catered for by the tourism accommodation sector. The need for this study reflects the increasingly significant role dogs are playing in the lives of humans, and the scale of the dog-owning population. The results suggest that, although there is a strong desire among dog owners to take holidays with their pets, the actualisation of this desire is comparatively low. A significant obstacle to the realisation of this desire appears to be a dearth of pet-friendly accommodation. This has implications for the ability of the tourism industry to benefit from this potentially lucrative market, that is, the dog-owning population

    Quantitative analysis of the morphological changes of the pubic symphyseal face and the auricular surface and implications for age at death estimation

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    YesAge estimation methods are often based on the age-related morphological changes of the auricular surface and the pubic bone. In this study, a mathematical approach to quantify these changes has been tested analyzing the curvature variation on 3D models from CT and laser scans. The sample consisted of the 24 Sucheyā€“Brooks (SB) pubic bone casts, 19 auricular surfaces from the Buckberry and Chamberlain (BC) ā€œrecording kitā€ and 98 pelvic bones from the Terry Collection (Smithsonian Institution). Strong and moderate correlations between phases and curvature were found in SB casts (Ļ 0.60ā€“0.93) and BC ā€œrecording kitā€ (Ļ 0.47ā€“0.75), moderate and weak correlations in the Terry Collection bones (pubic bones: Ļ 0.29ā€“0.51, auricular surfaces: Ļ 0.33ā€“0.50) but associated with large individual variability and overlap of curvature values between adjacent decades. The new procedure, requiring no expert judgment from the operator, achieved similar correlations that can be found in the classic methods

    Variations in Solar Luminosity from Time Scales of Minutes to Months

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    We present the power spectrum of solar irradiance during 1985 and 1987 obtained from the ACRIM project from time scales of minutes to months. At low frequency the spectra are Lorentzian. At higher frequencies they are proportional to fāˆ’1/2f^{-{1/2}}. A linear, stochastic model of the turbulent heat transfer between the granulation layer (modeled as a homogeneous thin layer with a radiative boundary condition) and the rest of the convection zone (modeled as a homogeneous thick layer with thermal and diffusion constants appropriate the lower convection zone) predicts the observed spectrum.Comment: latex file, 1 figur

    The challenge of designing for diversity in older users

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    Purpose: The older population is not a homogenous group and show significant diversity in constitution, capabilities and experience. In order for new and emerging digital technologies to be inclusive, it is crucial to encompass this diversity and employ a design process that is sensitive to it. Current approaches to inclusive design tend to seek one design for all, focusing on users who are least engaged with digital technology. In this paper we outline an alternative approach to inclusive design based on co-design with both digitally engaged and unengaged user groups. In our study, as part of a multi-disciplinary group in the New Dynamics of Ageing (UK) funded collaborative research project, older people from different walks of life were invited to four different themed workshops called ā€˜sandpitsā€™ to explore current and emerging technologies in a playful and creative context to help them envisage the potential implications these technologies can have in their lives as well as to identify key issues and user requirements for further development. This paper will discuss the outcome from three of those sandpits. The themes explored in these three sandpits were 1) Custom computers for older people 2) Supporting Identity and memory in later life and 3) Social connections with new technology. Methods. A total of 66 older people participated in the three sandpits conducted between 2009 and 2010. Separated into PC and non-PC users groups, they were involved in discussions and shown open ambiguous envisionments that responded to the themes through hands-on demonstration, role-play or dramatic enactment of their use. Broadly taking into account the role of technology generations effects, the envisionments were modeled and presented as appliances, incorporating forms of products and interactions that older people are familiar with to encourage in-clusion. The older participants were then involved in the redesign of these envisionments through a collaborative design process. Results and discussion The design responses from older PC and non-PC user groups revealed a difference in the type of embodiment they want for Internet-enabled applications. Both groups redesigned the concepts based on their experience, interests, familiarity with the technology they have and its associated infrastructure or lack thereof. In general, non-PC user groups preferred the appliance nature of the envisionments, and incorporated the functions they were interested in performing, such as capturing spoken stories, sharing photographs, chatting over TV programmes, etc into these appliances. In contrast, PC owners questioned the need for separate appliances and often re-designed them as PC applications or Internet services with emphasis placed on modality and compatibility with their existing infrastructure. The paper will discuss the difficulty and challenge of bridging the gap between the diversity of technology and its users

    Microbiology and atmospheric processes: Biological, physical and chemical characterization of aerosol particles

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    The interest in bioaerosols has traditionally been linked to health hazards for humans, animals and plants. However, several components of bioaerosols exhibit physical properties of great significance for cloud processes, such as ice nucleation and cloud condensation. To gain a better understanding of their influence on climate, it is therefore important to determine the composition, concentration, seasonal fluctuation, regional diversity and evolution of bioaerosols. In this paper, we will review briefly the existing techniques for detection, quantification, physical and chemical analysis of biological particles, attempting to bridge physical, chemical and biological methods for analysis of biological particles and integrate them with aerosol sampling techniques. We will also explore some emerging spectroscopy techniques for bulk and single-particle analysis that have potential for in-situ physical and chemical analysis. Lastly, we will outline open questions and further desired capabilities (e. g., in-situ, sensitive, both broad and selective, on-line, time-resolved, rapid, versatile, cost-effective techniques) required prior to comprehensive understanding of chemical and physical characterization of bioaerosols

    Using failed supernovae to constrain the Galactic r-process element production

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    Rapid neutron capture process (r-process) elements have been detected in a large fraction of metal-poor halo stars, with abundances relative to iron (Fe) that vary by over two orders of magnitude. This scatter is reduced to less than a factor of 3 in younger Galactic disc stars. The large scatter of r-process elements in the early Galaxy suggests that the r-process is made by rare events, like compact binary mergers and rare sub-classes of supernovae. Although being rare, neutron star mergers alone have difficulties to explain the observed enhancement of r-process elements in the lowest metallicity stars compared to Fe. The supernovae producing the two neutron stars already provide a substantial Fe abundance where the r-process ejecta from the merger would be injected. In this work we investigate another complementary scenario, where the r-process occurs in neutron star-black hole mergers in addition to neutron star mergers. Neutron star-black hole mergers would eject similar amounts of r-process matter as neutron star mergers, but only the neutron star progenitor would have produced Fe. Furthermore, a reduced efficiency of Fe production from single stars significantly alters the age-metallicity relation, which shifts the onset of r-process production to lower metallicities. We use the high-resolution [(20 pc)3/cell] inhomogeneous chemical evolution tool `ICE' to study the outcomes of these effects. In our simulations, an adequate combination of neutron star mergers and neutron star-black hole mergers qualitatively reproduces the observed r-process abundances in the Galaxy
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