481 research outputs found
Quantization of Soliton Cellular Automata
A method of quantization of classical soliton cellular automata (QSCA) is put
forward that provides a description of their time evolution operator by means
of quantum circuits that involve quantum gates from which the associated
Hamiltonian describing a quantum chain model is constructed.
The intrinsic parallelism of QSCA, a phenomenon first known from quantum
computers, is also emphasized.Comment: Latex, 6 pages, 1 figure in eps format included. Submitted to Journal
of Nonlinear Mathematical Physics. Special Issue of Proccedings of NEEDS'9
Long-run Social and Economic Responses of Fertility in the United States
Based on the results of an econometric analysis, the paper
looks into the dynamic response of fertility behaviour in the United
States, to changes in some of its determinants. Specifically, the effect
of current and past marriage rates on fertility has been studied. In
doing so, the role of permanent income and the divorce rate on the
marriage rate, and through it, on fertility, has also been
examined
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Bioactive natural products: facts, applications, and challenges
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Today, there are a strong debate and interest regarding the safety aspects of chemical preservatives addedwidely inmany food products to prevent mainly growth of spoilage and pathogenic microbes. Synthetic compounds are considered responsible for carcinogenic and teratogenic attributes and residual toxicity. To avoid the aforementioned problems, consumers and authorities have increased pressure on food manufacturers to substitute the harmful artificial additives with alternative, more effective, nontoxic, and natural sub-stances. In this context, the use of natural compounds with antimicrobial action presents an intriguing case. Natural antioxidants also demonstrate a wide range of biological and pharmacological activities and are considered to have bene
Simulator for Microlens Planet Surveys
We summarize the status of a computer simulator for microlens planet surveys.
The simulator generates synthetic light curves of microlensing events observed
with specified networks of telescopes over specified periods of time.
Particular attention is paid to models for sky brightness and seeing,
calibrated by fitting to data from the OGLE survey and RoboNet observations in
2011. Time intervals during which events are observable are identified by
accounting for positions of the Sun and the Moon, and other restrictions on
telescope pointing. Simulated observations are then generated for an algorithm
that adjusts target priorities in real time with the aim of maximizing planet
detection zone area summed over all the available events. The exoplanet
detection capability of observations was compared for several telescopes.Comment: Proc. IAU Symp. No. 293 "Formation, detection, and characterization
of extrasolar habitable planets", ed. by N. Haghighipour. 4 pages, in pres
A nonparametric Bayesian approach toward robot learning by demonstration
In the past years, many authors have considered application of machine learning methodologies to effect robot learning by demonstration. Gaussian mixture regression (GMR) is one of the most successful methodologies used for this purpose. A major limitation of GMR models concerns automatic selection of the proper number of model states, i.e., the number of model component densities. Existing methods, including likelihood- or entropy-based criteria, usually tend to yield noisy model size estimates while imposing heavy computational requirements. Recently, Dirichlet process (infinite) mixture models have emerged in the cornerstone of nonparametric Bayesian statistics as promising candidates for clustering applications where the number of clusters is unknown a priori. Under this motivation, to resolve the aforementioned issues of GMR-based methods for robot learning by demonstration, in this paper we introduce a nonparametric Bayesian formulation for the GMR model, the Dirichlet process GMR model. We derive an efficient variational Bayesian inference algorithm for the proposed model, and we experimentally investigate its efficacy as a robot learning by demonstration methodology, considering a number of demanding robot learning by demonstration scenarios
Systemic Redox Imbalance in Chronic Kidney Disease: A Systematic Review.
Patients with chronic kidney disease (CKD) experience imbalance between oxygen reactive species (ROS) production and antioxidant defenses leading to cell and tissue damage. However, it remains unclear at which stage of renal insufficiency the redox imbalance becomes more profound. The aim of this systematic review was to provide an update on recent advances in our understanding of how the redox status changes in the progression of renal disease from predialysis stages 1 to 4 to end stage 5 and whether the various treatments and dialysis modalities influence the redox balance. A systematic review was conducted searching PubMed and Scopus by using the Cochrane and PRISMA guidelines. In total, thirty-nine studies met the inclusion criteria and were reviewed. Even from an early stage, imbalance in redox status is evident and as the kidney function worsens it becomes more profound. Hemodialysis therapy per se seems to negatively influence the redox status by the elevation of lipid peroxidation markers, protein carbonylation, and impairing erythrocyte antioxidant defense. However, other dialysis modalities do not so far appear to confer advantages. Supplementation with antioxidants might assist and should be considered as an early intervention to halt premature atherogenesis development at an early stage of CKD
Developing Prognosis Tools to Identify Learning Difficulties in Children Using Machine Learning Technologies
The Mental Attributes Profiling System was developed in 2002 (Laouris and Makris, Proceedings of multilingual & cross-cultural perspectives on Dyslexia, Omni Shoreham Hotel, Washington, D.C, 2002), to provide a multimodal evaluation of the learning potential and abilities of young children’s brains. The method is based on the assessment of non-verbal abilities using video-like interfaces and was compared to more established methodologies in (Papadopoulos, Laouris, Makris, Proceedings of IDA 54th annual conference, San Diego, 2003), such as the Wechsler Intelligence Scale for Children (Watkins et al., Psychol Sch 34(4):309–319, 1997). To do so, various tests have been applied to a population of 134 children aged 7–12 years old. This paper addresses the issue of identifying a minimal set of variables that are able to accurately predict the learning abilities of a given child. The use of Machine Learning technologies to do this provides the advantage of making no prior assumptions about the nature of the data and eliminating natural bias associated with data processing carried out by humans. Kohonen’s Self Organising Maps (Kohonen, Biol Cybern 43:59–69, 1982) algorithm is able to split a population into groups based on large and complex sets of observations. Once the population is split, the individual groups can then be probed for their defining characteristics providing insight into the rationale of the split. The characteristics identified form the basis of classification systems that are able to accurately predict which group an individual will belong to, using only a small subset of the tests available. The specifics of this methodology are detailed herein, and the resulting classification systems provide an effective tool to prognose the learning abilities of new subjects
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