6,183 research outputs found
Small amplitude lateral sloshing in a cylindrical tank with a hemispherical bottom under low gravitational conditions Summary report
Small amplitude lateral sloshing in cylindrical tank with hemispherical bottom under low gravitational condition
Holography in the EPRL Model
In this research announcement, we propose a new interpretation of the EPR
quantization of the BC model using a functor we call the time functor, which is
the first example of a CLa-ren functor. Under the hypothesis that the universe
is in the Kodama state, we construct a holographic version of the model.
Generalisations to other CLa-ren functors and connections to model category
theory are considered.Comment: research announcement. Latex fil
Matrix bandwidth and profile reduction
This program, REDUCE, reduces the bandwidth and profile of sparse symmetric matrices, using row and corresponding column permutations. It is a realization of the algorithm described by the authors elsewhere. It was extensively tested and compared with several other programs and was found to be considerably faster than the others, superior for bandwidth reduction and as satisfactory as any other for profile reduction
A qualitative study of autism services and supports in Singapore: perspectives of service providers, autistic adults, and caregivers
The lifelong and complex nature of autism necessitates an array of services and supports spanning across different sectors and providers at different life stages of an autistic individual. However, research has shown that autistic individuals and their families often experience barriers accessing the autism-related services and supports that they need. This is the first qualitative study to explore the provision and coordination of autism services and supports in Singapore from the perspectives of service providers, autistic adults and caregivers. Semi-structured interviews with 21 participants revealed three main themes: (1) improving access to autism-specific services, (2) creating flexible supports in an inclusive environment and (3) addressing stigma and changing societal attitudes. Our findings suggest that Singapore may have achieved rapid growth in autism services, but broader social structures may be slower to change. To better support autistic individuals in society, autistic voices need to be amplified and a collective effort is needed to achieve a paradigm shift from impairment to capability
Participatory autism research: early career and established researchers’ views and experiences
Despite more autism research taking place than ever before, there is a disconnect between the current landscape of autism research and what autistic people and their allies want from research. While participatory research has been proposed as a potential solution, we know little about how researchers (particularly, early career researchers) employ this approach. We interviewed 25 researchers (14 early career and 11 established researchers) about their views and experiences of participatory autism research. Through reflexive thematic analysis of interview and focus group data, we identified three themes. First, our participants emphasised the flexible nature of participatory research, and the many forms it can take; yet noted that this flexibility could cause confusion. Second, our participants highlighted the importance of building relationships with research partners, while commenting on the challenges around effective communication and working with diverse groups of people who may have limited research experience. Finally, participants described the challenges of working within academic environments that are not conducive to participatory research (e.g. due to limited time, funding and support). We discuss these issues with regard to changes required at both an individual and systemic level, ensuring that efforts are made to meaningfully involve autistic people and their allies in all stages of the research process
The Influence of Thin Bonding Layers on the Leaky Waves at Liquid-Solid Interfaces
This paper presents theoretical and experimental results on the problem of bounded acoustic beam reflection at the Rayleigh angle from a fluid-solid interface which is loaded by a thin solid layer. The theoretical development exploits the framework of existing theory to yield a simple, analytic model which is reasonably accurate for thin layers. It is shown that the influence of the layer is contained entirely in the dispersive Rayleigh wavespeed and the thickness-dependent displacement parameter Δs. Measurements of the reflected acoustic field amplitude have been performed on several samples of stainless steel loaded with a thin copper layer. We have found reasonably good agreement between the theoretical model calculations and experimental measurements for ratios of the layer thickness to the Rayleigh wavelength as large as 0.3. Beyond this value, some disparity is observed, particularly in the calculation of the thickness-dependent Rayleigh wavespeed
Spin Networks and Quantum Gravity
We introduce a new basis on the state space of non-perturbative quantum
gravity. The states of this basis are linearly independent, are well defined in
both the loop representation and the connection representation, and are labeled
by a generalization of Penrose's spin netoworks. The new basis fully reduces
the spinor identities (SU(2) Mandelstam identities) and simplifies calculations
in non-perturbative quantum gravity. In particular, it allows a simple
expression for the exact solutions of the Hamiltonian constraint
(Wheeler-DeWitt equation) that have been discovered in the loop representation.
Since the states in this basis diagnolize operators that represent the three
geometry of space, such as the area and volumes of arbitrary surfaces and
regions, these states provide a discrete picture of quantum geometry at the
Planck scale.Comment: 42 page
Honey Yield Forecast Using Radial Basis Functions
Honey yields are difficult to predict and have been usually
associated with weather conditions. Although some specific meteorological
variables have been associated with honey yields, the reported relationships
concern a specific geographical region of the globe for a given
time frame and cannot be used for different regions, where climate may
behave differently. In this study, Radial Basis Function (RBF) interpolation
models were used to explore the relationships between weather variables
and honey yields. RBF interpolation models can produce excellent
interpolants, even for poorly distributed data points, capable of mimicking
well unknown responses providing reliable surrogates that can
be used either for prediction or to extract relationships between variables.
The selection of the predictors is of the utmost importance and an
automated forward-backward variable screening procedure was tailored
for selecting variables with good predicting ability. Honey forecasts for
Andalusia, the first Spanish autonomous community in honey production,
were obtained using RBF models considering subsets of variables
calculated by the variable screening procedure
The accommodative ciliary muscle function is preserved in older humans
Presbyopia, the loss of the eye’s accommodation capability, affects all humans aged above 45–50 years old. The two main reasons for this to happen are a hardening of the crystalline lens and a reduction of the ciliary muscle functionality with age. While there seems to be at least some partial accommodating functionality of the ciliary muscle at early presbyopic ages, it is not yet clear whether the muscle is still active at more advanced ages. Previous techniques used to visualize the accommodation mechanism of the ciliary muscle are complicated to apply in the older subjects, as they typically require fixation stability during long measurement times and/or to have an ultrasound probe directly in contact with the eye. Instead, we used our own developed method based on high-speed recording of lens wobbling to study the ciliary muscle activity in a small group of pseudophakic subjects (around 80 years old). There was a significant activity of the muscle, clearly able to contract under binocular stimulation of accommodation. This supports a purely lenticular-based theory of presbyopia and it might stimulate the search for new solutions to presbyopia by making use of the remaining contraction force still presented in the aging eye
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