4,774 research outputs found
Estimation of the mechanical properties of the eye through the study of its vibrational modes
Measuring the eye's mechanical properties in vivo and with minimally invasive
techniques can be the key for individualized solutions to a number of eye
pathologies. The development of such techniques largely relies on a
computational modelling of the eyeball and, it optimally requires the synergic
interplay between experimentation and numerical simulation. In Astrophysics and
Geophysics the remote measurement of structural properties of the systems of
their realm is performed on the basis of (helio-)seismic techniques. As a
biomechanical system, the eyeball possesses normal vibrational modes
encompassing rich information about its structure and mechanical properties.
However, the integral analysis of the eyeball vibrational modes has not been
performed yet. Here we develop a new finite difference method to compute both
the spheroidal and, specially, the toroidal eigenfrequencies of the human eye.
Using this numerical model, we show that the vibrational eigenfrequencies of
the human eye fall in the interval 100 Hz - 10 MHz. We find that compressible
vibrational modes may release a trace on high frequency changes of the
intraocular pressure, while incompressible normal modes could be registered
analyzing the scattering pattern that the motions of the vitreous humour leave
on the retina. Existing contact lenses with embebed devices operating at high
sampling frequency could be used to register the microfluctuations of the
eyeball shape we obtain. We advance that an inverse problem to obtain the
mechanical properties of a given eye (e.g., Young's modulus, Poisson ratio)
measuring its normal frequencies is doable. These measurements can be done
using non-invasive techniques, opening very interesting perspectives to
estimate the mechanical properties of eyes in vivo. Future research might
relate various ocular pathologies with anomalies in measured vibrational
frequencies of the eye.Comment: Published in PLoS ONE as Open Access Research Article. 17 pages, 5
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Report on the Information Retrieval Festival (IRFest2017)
The Information Retrieval Festival took place in April 2017 in Glasgow. The focus of the workshop was to bring together IR researchers from the various Scottish universities and beyond in order to facilitate more awareness, increased interaction and reflection on the status of the field and its future. The program included an industry session, research talks, demos and posters as well as two keynotes. The first keynote was delivered by Prof. Jaana Kekalenien, who provided a historical, critical reflection of realism in Interactive Information Retrieval Experimentation, while the second keynote was delivered by Prof. Maarten de Rijke, who argued for more Artificial Intelligence usage in IR solutions and deployments. The workshop was followed by a "Tour de Scotland" where delegates were taken from Glasgow to Aberdeen for the European Conference in Information Retrieval (ECIR 2017
Implementing feedback in creative systems : a workshop approach
One particular challenge in AI is the computational modelling and simulation of creativity. Feedback and learning from experience are key aspects of the creative process. Here we investigate how we could implement feedback in creative systems using a social model. From the field of creative writing we borrow the concept of a Writers Workshop as a model for learning through feedback. The Writers Workshop encourages examination, discussion and debates of a piece of creative work using a prescribed format of activities. We propose a computational model of the Writers Workshop as a roadmap for incorporation of feedback in artificial creativity systems. We argue that the Writers Workshop setting describes the anatomy of the creative process. We support our claim with a case study that describes how to implement the Writers Workshop model in a computational creativity system. We present this work using patterns other people can follow to implement similar designs in their own systems. We conclude by discussing the broader relevance of this model to other aspects of AI
Generality, Specificity And Discovery
This paper offers a meta-theory concerning the relation between the general and the specific in science. This issue was recently called back to attention by Hodgson (2001). A heuristic of discovery, developed in earlier work (Nooteboom 1992, 1996, 1999b, 2000a), is used in an attempt to contribute to an understanding and a resolution of the tension between generality and specificity. That tension can be resolved if we look at general theory and specific conditions (or data, experience) not as separate entities or approaches that one has to choose from, in a static perspective, thus choosing to be a generalist or an empiricist, but as complementary, in a dynamic, dialectical process of theory development, in the process of discovery. The paper argues that there is an alternation of the general and the specific, in an ongoing cycle of formation and application of theory. Generalisation and abstraction are necessary to lift experience from specific contexts and carry it into new contexts with their own specificity. That, in turn, is needed for the theory to face failure and collect the experience that will lead to new generalisation. In the face of failure, adaptations are made to the specific context, in differentiation, and hints are found for novel specific elements to be absorbed, which yields hybridisation. This exerts pressure, and provides the material and the directions, to develop a new unity out of novel combinations, and we are back at the beginning of the cycle.learning;discovery;generality;specificity
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