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Photonic neural networks

Damien Woods, Thomas J. Naughton
2012 Nature Physics  
Thomas J.  ...  Damien Woods and Thomas J. Naughton news & views enable it to achieve results comparable to the state of the art for hard problems such as speech recognition [1] [2] [3] .  ... 
doi:10.1038/nphys2283 fatcat:pqsf7zjz25grrk4snvjw7hcoby

Optical computing

Damien Woods, Thomas J. Naughton
2009 Applied Mathematics and Computation  
The model was originally proposed by Naughton [63, 64] .  ... 
doi:10.1016/j.amc.2009.04.061 fatcat:yhphz7qi4vdcvm6f3o7qokq4wu

Optical Computing [chapter]

Thomas J. Naughton, Damien Woods
2009 Encyclopedia of Complexity and Systems Science  
Optical computing is the use of photons in computation. Photons, effectively massless and incredibly fast, are generated using diodes or lasers. The photons take the place of electrons in more traditional computers and are used to represent the flow of data. Lacking the size limitation of electrons, photon based transistors can be incredibly small which increases potential computing power.
doi:10.1007/978-0-387-30440-3_377 fatcat:k3wstnn6vvbsfn3jy6uh2qg3ju

Parallel and Sequential Optical Computing [chapter]

Damien Woods, Thomas J. Naughton
2008 Lecture Notes in Computer Science  
The model was originally proposed by Naughton [17, 18] . The CSM computes in discrete timesteps over a number of two-dimensional images of fixed size and arbitrary spatial resolution.  ... 
doi:10.1007/978-3-540-85673-3_6 fatcat:6cj6eid7pvgqzpftnr5m5qxi4a

Signaling Through Corporate Accountability Reporting

Thomas Z. Lys, James P. Naughton, Clare Wang
2012 Social Science Research Network  
We examine whether the content of a firm's corporate accountability report provides information about the future financial prospects of the firm. We find that corporate social responsibility ("CSR") expenditures do not improve future financial performance. Rather, firms undertake CSR investments in the current period in anticipation of stronger future financial performance. We show that the causality of the positive association between CSR investments and future firm performance is different
more » ... m what is claimed in the vast majority of the literature, and that corporate accountability disclosures are another channel by which firms convey financial prospects to outsiders. JEL classification: M41, D82, G14, G30, G32, G34
doi:10.2139/ssrn.2143259 fatcat:zdjenatum5fm5pkkn2f7ssph7u

An optical model of computation

Damien Woods, Thomas J. Naughton
2005 Theoretical Computer Science  
We prove computability and complexity results for an original model of computation called the continuous space machine. Our model is inspired by the theory of Fourier optics. We prove our model can simulate analog recurrent neural networks, thus establishing a lower bound on its computational power. We also define a (log 2 n) unordered search algorithm with our model.
doi:10.1016/j.tcs.2004.07.001 fatcat:zxfez3gyp5gqvoab24vymdfcrq

A Characterization of the Prime Graphs of Solvable Groups [article]

Alexander Gruber, Thomas Keller, Mark Lewis, Keeley Naughton, Benjamin Strasser
2013 arXiv   pre-print
Let π(G) denote the set of prime divisors of the order of a finite group G. The prime graph of G is the graph with vertex set π(G) with edges p,q if and only if there exists an element of order pq in G. In this paper, we prove that a graph is isomorphic to the prime graph of a solvable group if and only if its complement is 3-colorable and triangle free. We then introduce the idea of a minimal prime graph. We prove that there exists an infinite class of solvable groups whose prime graphs are
more » ... imal. We prove the 3k-conjecture on prime divisors in element orders for solvable groups with minimal prime graphs, and we show that solvable groups whose prime graphs are minimal have Fitting length 3 or 4.
arXiv:1305.2368v1 fatcat:h3gihdm5vzdmtftse7haf4xixa

Multiwavefront digital holographic television

Malgorzata Kujawinska, Tomasz Kozacki, Claas Falldorf, Thomas Meeser, Bryan M. Hennelly, Piotr Garbat, Weronika Zaperty, Mikko Niemelä, Grzegorz Finke, Marcin Kowiel, Thomas Naughton
2014 Optics Express  
This paper presents the full technology chain supporting wide angle digital holographic television from holographic capture of real world objects/scenes to holographic display with an extended viewing angle. The data are captured with multiple CCD cameras located around an object. The display system is based on multiple tilted spatial light modulators (SLMs) arranged in a circular configuration. The capture-display system is linked by a holographic data processing module, which allows for
more » ... icant decoupling of the capture and display systems. The presented experimental results, based on the reconstruction of real world, variable in time scenes, illustrates imaging dynamics, viewing angle and quality.
doi:10.1364/oe.22.002324 pmid:24663525 fatcat:yad5b24ksfb23c67myigowvinu

Building Large Phylogenetic Trees on Coarse-Grained Parallel Machines

Thomas M. Keane, Andrew J. Page, Thomas J. Naughton, Simon A.A. Travers, James O. McInerney
2006 Algorithmica  
Phylogenetic analysis is an area of computational biology concerned with the reconstruction of evolutionary relationships between organisms, genes, and gene families. Maximum likelihood evaluation has proven to be one of the most reliable methods for constructing phylogenetic trees. The huge computational requirements associated with maximum likelihood analysis means that it is not feasible to produce large phylogenetic trees using a single processor. We have completed a fully cross platform
more » ... rse grained distributed application, DPRml, which overcomes many of the limitations imposed by the current set of parallel phylogenetic programs. We have completed a set of efficiency tests that show how to maximise efficiency while using the program to build large phylogenetic trees. The software is publicly available under the terms of the GNU general public licence from the system webpage at
doi:10.1007/s00453-006-1215-0 fatcat:bbfmahf7cba6pbqouys7zdlxju

Characterizing the Performance of Executing Many-tasks on Summit [article]

Matteo Turilli, Andre Merzky, Thomas Naughton, Wael Elwasif, Shantenu Jha
2019 arXiv   pre-print
Many scientific workloads are comprised of many tasks, where each task is an independent simulation or analysis of data. The execution of millions of tasks on heterogeneous HPC platforms requires scalable dynamic resource management and multi-level scheduling. RADICAL-Pilot (RP) -- an implementation of the Pilot abstraction, addresses these challenges and serves as an effective runtime system to execute workloads comprised of many tasks. In this paper, we characterize the performance of
more » ... g many tasks using RP when interfaced with JSM and PRRTE on Summit: RP is responsible for resource management and task scheduling on acquired resource; JSM or PRRTE enact the placement of launching of scheduled tasks. Our experiments provide lower bounds on the performance of RP when integrated with JSM and PRRTE. Specifically, for workloads comprised of homogeneous single-core, 15 minutes-long tasks we find that: PRRTE scales better than JSM for > O(1000) tasks; PRRTE overheads are negligible; and PRRTE supports optimizations that lower the impact of overheads and enable resource utilization of 63% when executing O(16K), 1-core tasks over 404 compute nodes.
arXiv:1909.03057v1 fatcat:r27ug22ahzespkzpl6ocxsrzlu

General-purpose acousto-optic connectionist processor

Thomas Naughton
1999 Optical Engineering: The Journal of SPIE  
Naughton et al.: General-purpose acousto-optic connectionist processor Fig. 4 4 Input signal for the interaction height experiments that simulates a portion of the LCD panel with arbitrary pixels turned  ...  Thomas Naughton received his BSc in computer science and experimental physics in 1995 from the National University of Ireland, Maynooth (previously St.  ...  Naughton holds one patent and is a member of SPIE, OSA, IEEE and ACM.  ... 
doi:10.1117/1.602167 fatcat:dy4iawhi5zeczdx5m6jpzfiaam

Exercise for type 2 diabetes mellitus

Diana Thomas, Elizabeth J Elliott, Geraldine A Naughton
2006 The Cochrane library  
GAContribution of author(s)Diana Thomas: co-ordinated the review process, searched for trials, screened the search results, assessed the trials for quality, extracted data, analysed data, developed the  ...  Randomized Controlled Trials; Subcutaneous Fat [pathology]; Weight Loss MeSH check words Female; Humans; MaleC O V E R S H E E T TitleExercise for type 2 diabetes mellitusAuthorsThomas DE, Elliott EJ, Naughton  ... 
doi:10.1002/14651858.cd002968.pub2 pmid:16855995 pmcid:PMC8989410 fatcat:6zqlonozgbbdtgkxvdg4wsyfuu

Stereo vision based approach for extracting features from digital holograms [chapter]

Tomi Pitkäaho, Thomas J. Naughton
2009 Fringe 2009  
doi:10.1007/978-3-642-03051-2_95 fatcat:z2qrc6he6fe3bgyze7w7yugcau

Signaling through corporate accountability reporting

Thomas Lys, James P. Naughton, Clare Wang
2015 Journal of Accounting & Economics  
We examine whether the content of a firm's corporate accountability report provides information about the future financial prospects of the firm. We find that corporate social responsibility ("CSR") expenditures do not improve future financial performance. Rather, firms undertake CSR investments in the current period in anticipation of stronger future financial performance. We show that the causality of the positive association between CSR investments and future firm performance is different
more » ... m what is claimed in the vast majority of the literature, and that corporate accountability disclosures are another channel by which firms convey financial prospects to outsiders. JEL classification: M41, D82, G14, G30, G32, G34
doi:10.1016/j.jacceco.2015.03.001 fatcat:kmvpq2hmkbdeld7lobnn32p564

Calculating depth maps from digital holograms using stereo disparity

Tomi Pitkäaho, Thomas J. Naughton
2011 Optics Letters  
Depth extraction is an important aspect of three-dimensional (3D) image processing with digital holograms and an essential step in extended focus imaging and metrology. All available depth extraction techniques with macroscopic objects are based on variance; however, the effectiveness of this is object dependent. We propose to use disparity between corresponding points in intensity reconstructions to determine depth. Our method requires a single hologram of a scene, from which we reconstruct
more » ... different perspectives. In the reconstruction the phase information is not needed, which makes this method useful for in-line digital holography. To our knowledge disparity based 3D image processing has never been proposed before for digital holography.
doi:10.1364/ol.36.002035 pmid:21633440 fatcat:qmiqrlcgcvd23dklbrvfvu5hoi
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