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Articles 271 - 300 of 2524

Full-Text Articles in Physical Sciences and Mathematics

Basin Of Attraction Of Periodic Orbits Of Maps On The Real Line, Saber Elaydi, Robert Sacker Aug 2015

Basin Of Attraction Of Periodic Orbits Of Maps On The Real Line, Saber Elaydi, Robert Sacker

Saber Elaydi

We prove a conjecture by Elaydi and Yakubu which states that the basin of attraction of an attracting 2 k -cycle of the Ricker's map is where E is the set of all eventually 2 r -periodic points. The result is then extended to a more general class of continuous maps on the real line.

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Poincaré Types Solutions Of Systems Of Difference Equations, Raghib Abu-Saris, Saber Elaydi, Sophia Jang Aug 2015

Poincaré Types Solutions Of Systems Of Difference Equations, Raghib Abu-Saris, Saber Elaydi, Sophia Jang

Saber Elaydi

No abstract provided.

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Pixley-Roy Hyperspaces Of Ω-Graphs, Joe Mashburn Jul 2015

Pixley-Roy Hyperspaces Of Ω-Graphs, Joe Mashburn

Joe D. Mashburn

The techniques developed by Wage and Norden are used to show that the Pixley-Roy hyperspaces of any two ω-graphs are homeomorphic. The Pixley-Roy hyperspaces of several subsets of Rn are also shown to be homeomorphic.

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Countable Covers Of Spaces By Migrant Sets, Zoltan Balogh, Joe Mashburn, Peter Nyikos Jul 2015

Countable Covers Of Spaces By Migrant Sets, Zoltan Balogh, Joe Mashburn, Peter Nyikos

Joe D. Mashburn

The motivation for this note is a paper by Hidenori Tanaka in which he shows that the Pixley-Roy hyperspace of a metric space X is normal if and only if X is an almost strong q-set.

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Linearly Ordered Topological Spaces And Weak Domain Representability, Joe Mashburn Jul 2015

Linearly Ordered Topological Spaces And Weak Domain Representability, Joe Mashburn

Joe D. Mashburn

It is well known that domain representable spaces, that is topological spaces that are homeomorphic to the space of maximal elements of some domain, must be Baire. In this paper it is shown that every linearly ordered topological space (LOTS) is homeomorphic to an open dense subset of a weak domain representable space. This means that weak domain representable spaces need not be Baire.

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Advances In Fetal Heart Rate Monitoring Using Smart Phones, Chang Su Lee, Martin Masek, Chiou Peng Lam, Keng Tiong Tan Jul 2015

Advances In Fetal Heart Rate Monitoring Using Smart Phones, Chang Su Lee, Martin Masek, Chiou Peng Lam, Keng Tiong Tan

Martin Masek

It has been shown that the rate of preterm birth in remote and rural populations in Australia is more than twice of those in the metropolitan population, and that increased access to quality antenatal care in such communities leads to a significant improvement. This paper describes a system that supports remote fetal heart rate monitoring, thus providing a technique that addresses this need for better remote antenatal care. The application involves a smart phone, a portable Doppler ultrasound device, a remote back-end server and network connectivity provided by the global system for mobile communications (GSM) and general packet radio service …

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Remote Home-Based Ante And Post Natal Care, Martin Masek, Chang Su Lee, Chiou Peng Lam, Keng Tiong Tan, Angela Fyneman Jul 2015

Remote Home-Based Ante And Post Natal Care, Martin Masek, Chang Su Lee, Chiou Peng Lam, Keng Tiong Tan, Angela Fyneman

Martin Masek

Australia is geographically large and sparsely populated. Thus, its population is subject to inequalities in healthcare based on geographic location. This is particularly true for the management of pregnancies at risk, which require regular monitoring. We discuss a solution in the form of a framework based on inexpensive monitoring devices coupled with a mobile phone and PC systems to enable enhanced monitoring capabilities and remote connectivity. The system has the potential to reduce unnecessary travel for regular checkups. Importantly, this system allows monitoring and diagnosis, as well as support for the mother, to be available remotely at any time allowing …

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Wambot: Simulation And Modelling Of A Team Of Autonomous Mobile Robots, Martin Masek, Frank Ophelders, Sushil Pangeni, Adrian Boeing, Thomas Braunl Jul 2015

Wambot: Simulation And Modelling Of A Team Of Autonomous Mobile Robots, Martin Masek, Frank Ophelders, Sushil Pangeni, Adrian Boeing, Thomas Braunl

Martin Masek

Simulation is an essential early evaluation tool for mobile robot research and development, and different stages of development have individual simulator needs. In this paper, we document details of two simulation tools that were developed for an entry into the MAGIC 2010 challenge, an autonomous ground vehicle competition. In developing the entry, simulators were used in two domains: problem analysis and solution testing. The problem analysis simulator was built using a commercial 3D game engine, whilst the simulator aimed at testing of the solution was built using a standard robotics library. By leveraging existing technologies appropriate for each domain, the …

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Rough-Fuzzy Hybrid Approach For Identification Of Bio-Markers And Classification On Alzheimer's Disease Data, Changsu Lee, Chiou-Peng Lam, Martin Masek Jul 2015

Rough-Fuzzy Hybrid Approach For Identification Of Bio-Markers And Classification On Alzheimer's Disease Data, Changsu Lee, Chiou-Peng Lam, Martin Masek

Martin Masek

A new approach is proposed in this paper for identification of biomarkers and classification on Alzheimer's disease data by employing a rough-fuzzy hybrid approach called ARFIS (a framework for Adaptive TS-type Rough-Fuzzy Inference Systems). In this approach, the entropy-based discretization technique is employed first on the training data to generate clusters for each attribute with respect to the output information. The rough set-based feature reduction method is then utilized to reduce the number of features in a decision table obtained using the cluster information. Another rough set-based approach is employed for the generation of decision rules. After the construction and …

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Activities Of Daily Living Classification Using Depth Features, Laurence Da Luz, Martin Masek, Chiou Peng Lam Jul 2015

Activities Of Daily Living Classification Using Depth Features, Laurence Da Luz, Martin Masek, Chiou Peng Lam

Martin Masek

The increasing elderly population presents a challenge on the resources of carers and assisted living communities. In this paper, we present an algorithm based around the Microsoft Kinect for monitoring activities of daily living. The system analyses the behaviour of occupants to provide carers with valuable observational data, and has the capacity to detect abnormal events in the home.

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Experiments With Monte Carlo Othello, Philip Hingston, Martin Masek Jul 2015

Experiments With Monte Carlo Othello, Philip Hingston, Martin Masek

Martin Masek

In this paper, we report on our experiments with using Monte Carlo simulation (specifically the UCT algorithm) as the basis for an Othello playing program. Monte Carlo methods have been used for other games in the past, most recently and notably in successful Go playing programs. We show that Monte Carlo-based players have potential for Othello, and that evolutionary algorithms can be used to improve their strength.

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The Effects Of Diversity Maintenance On Coevolution For An Intransitive Numbers Problem, Tirtha Ranjeet, Martin Masek, Philip Hingston, Chiou Peng Lam Jul 2015

The Effects Of Diversity Maintenance On Coevolution For An Intransitive Numbers Problem, Tirtha Ranjeet, Martin Masek, Philip Hingston, Chiou Peng Lam

Martin Masek

In this paper, we investigate the effectiveness of several techniques commonly recommended for overcoming convergence problems with coevolutionary algorithms. In particular, we investigate effects of the Hall of Fame, and of several diversity maintenance methods, on a problem designed to test the ability of coevolutionary algorithms to deal with an intransitive superiority relation between solutions. We measure and analyse the effects of these methods on population diversity and on solution quality.

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A Comparison Of Three Topologies On Ordered Sets, Joe Mashburn Jul 2015

A Comparison Of Three Topologies On Ordered Sets, Joe Mashburn

Joe D. Mashburn

We introduce two new topologies on ordered sets: the way below topology and weakly way below topology. These are similar in definition to the Scott topology, but are very different if the set is not continuous. The basic properties of these three topologies are compared. We will show that while domain representable spaces must be Baire, this is not the case with the new topologies.

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Magnetism Of Zno Nanoparticles: Dependence On Crystallite Size And Surfactant Coating, Aaron Thurber, Geoffrey Beausoleil, Gordon Alanko, Joshua Anghel, Michael Jones, Lydia Johnson, Jianhui Zhang, Charles Hanna, Dmitri Tenne, Alex Punnoose Jul 2015

Magnetism Of Zno Nanoparticles: Dependence On Crystallite Size And Surfactant Coating, Aaron Thurber, Geoffrey Beausoleil, Gordon Alanko, Joshua Anghel, Michael Jones, Lydia Johnson, Jianhui Zhang, Charles Hanna, Dmitri Tenne, Alex Punnoose

Lydia Johnson

Many recent reports on magnetism in otherwise nonmagnetic oxides have demonstrated that nanoparticle size, surfactant coating, or doping with magnetic ions produces room-temperature ferromagnetism. Specifically, ZnO has been argued to be a room-temperature ferromagnet through all three of these methods in various experimental studies. For this reason, we have prepared a series of 1% Fe doped ZnO nanoparticle samples using a single forced hydrolysis co-precipitation synthesis method from the same precursors, while varying size (6 – 15 nm) and surface coating concentration to study the combined effects of these two parameters. Size was controlled by modifying the water concentration. Surfactant …

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Come For The Content, Stay For The Community, Hilary Eppley Jul 2015

Come For The Content, Stay For The Community, Hilary Eppley

Hilary J. Eppley

No abstract provided.

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Global Dynamics Of Triangular Maps, Eduardo Balreira, Saber Elaydi, Rafael Luis Jul 2015

Global Dynamics Of Triangular Maps, Eduardo Balreira, Saber Elaydi, Rafael Luis

Saber Elaydi

We consider continuous triangular maps on IN, where I is a compact interval in the Euclidean space R. We show, under some conditions, that the orbit of every point in a triangular map converges to a fixed point if and only if there is no periodic orbit of prime period two. As a consequence we obtain a result on global stability, namely, if there are no periodic orbits of prime period 2 and the triangular map has a unique fixed point, then the fixed point is globally asymptotically stable. We also discuss examples and applications of our results to competition …

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Local Stability Implies Global Stability For The Planar Ricker Competition Model, Eduardo Balreira, Saber Elaydi, Rafael Luis Jul 2015

Local Stability Implies Global Stability For The Planar Ricker Competition Model, Eduardo Balreira, Saber Elaydi, Rafael Luis

Saber Elaydi

Under certain analytic and geometric assumptions we show that local stability of the coexistence (positive) fixed point of the planar Ricker competition model implies global stability with respect to the interior of the positive quadrant. This result is a confluence of ideas from Dynamical Systems, Geometry, and Topology that provides a framework to the study of global stability for other planar competition models.

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Population Models In Almost Periodic Environments, Toka Diagana, Saber Elaydi, Abdul-Aziz Yakubu Jul 2015

Population Models In Almost Periodic Environments, Toka Diagana, Saber Elaydi, Abdul-Aziz Yakubu

Saber Elaydi

We establish the basic theory of almost periodic sequences on Z+. Dichotomy techniques are then utilized to find sufficient conditions for the existence of a globally attracting almost periodic solution of a semilinear system of difference equations. These existence results are, subsequently, applied to discretely reproducing populations with and without overlapping generations. Furthermore, we access evidence for attenuance and resonance in almost periodically forced population models.

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Stability And Asymptoticity Of Volterra Difference Equations: A Progress Report, Saber Elaydi Jul 2015

Stability And Asymptoticity Of Volterra Difference Equations: A Progress Report, Saber Elaydi

Saber Elaydi

We survey some of the fundamental results on the stability and asymptoticity of linear Volterra difference equations. The method of Z-transform is heavily utilized in equations of convolution type. An example is given to show that uniform asymptotic stability does not necessarily imply exponential stabilty. It is shown that the two notions are equivalent if the kernel decays exponentially. For equations of nonconvolution type, Liapunov functions are used to find explicit criteria for stability. Moreover, the resolvent matrix is defined to produce a variation of constants formula. The study of asymptotic equivalence for difference equations with infinite delay is carried …

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On The Asymptotic Stability Of Linear Volterra Difference Equations Of Convolution Type, Saber Elaydi, E Messina, A Vecchio Jul 2015

On The Asymptotic Stability Of Linear Volterra Difference Equations Of Convolution Type, Saber Elaydi, E Messina, A Vecchio

Saber Elaydi

No abstract provided.

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An Economical Model With Allee Effect, Rafael Luis, Saber Elaydi, Henrique Oliveira Jul 2015

An Economical Model With Allee Effect, Rafael Luis, Saber Elaydi, Henrique Oliveira

Saber Elaydi

The Marx model for the profit rate r depending on the exploitation rate e and on the organic composition of the capital k is studied using a dynamical approach. Supposing both e(t) and k(t) are continuous functions of time we derive a law for r(t) in the long term. Depending upon the hypothesis set on the growth of k(t) and e(t) in the long term, r(t) can fall to zero or remain constant. This last case contradicts the classical hypothesis of Marx stating that the profit rate must decrease in the long term. Introducing a discrete dynamical system in the …

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Non-Autonomous Periodic Systems With Allee Effects, Rafael Luis, Saber Elaydi, Henrique Oliveira Jul 2015

Non-Autonomous Periodic Systems With Allee Effects, Rafael Luis, Saber Elaydi, Henrique Oliveira

Saber Elaydi

A new class of maps called unimodal Allee maps are introduced. Such maps arise in the study of population dynamics in which the population goes extinct if its size falls below a threshold value. A unimodal Allee map is thus a unimodal map with tree fixed points, a zero fixed point, a small positive fixed point, called threshold point, and a bigger positive fixed point, called the carrying capacity. In this paper the properties and stability of the three fixed points are studied in the setting of nonautonomous periodic dynamical systems or difference equations. Finally we investigate the bifurcation of …

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Towards A Theory Of Periodic Difference Equations And Its Application To Population Dynamics, Saber Elaydi, Rafael Luis, Henrique Oliveira Jul 2015

Towards A Theory Of Periodic Difference Equations And Its Application To Population Dynamics, Saber Elaydi, Rafael Luis, Henrique Oliveira

Saber Elaydi

This survey contains the most updated results on the dynamics of periodic difference equations or discrete dynamical systems this time. Our focus will be on stability theory, bifurcation theory, and on the effect of periodic forcing on the welfare of the population (attenuance versus resonance). Moreover, the survey alludes to two more types of dynamical systems, namely, almost periodic difference equations and stochastic di®erence equations.

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Technology Professional Development: Long-Term Effects On Teacher Self-Efficacy, George Watson Jul 2015

Technology Professional Development: Long-Term Effects On Teacher Self-Efficacy, George Watson

George R Watson

The West Virginia K-12 RuralNet Project was an NSF funded program to train inservice teachers on integrating the Internet into science and mathematics curriculum. The program involved training inservice teachers through an intensive summer workshop and supplemental online courses. This study examines the effects of the project on the long-term self-efficacy of inservice teachers and their use of the Internet in the classroom. The specific research questions addressed are: Do professional development programs affect the long-term self-efficacy of inservice teachers? Did the addition of online courses and follow-up to the program affect self-efficacy levels? Finally, do certain external factors, specifically …

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Geospatial Decision Support For Drought Risk Management , Steve Goddard, Sherri Harms, Stephen Reichenbach, Tsegaye Tadesse, William Waltman Jul 2015

Geospatial Decision Support For Drought Risk Management , Steve Goddard, Sherri Harms, Stephen Reichenbach, Tsegaye Tadesse, William Waltman

Steve Reichenbach

Drought affects virtually all regions of the world and results in significant economic, social, and environmental impacts. The Federal Emergency Management Agency estimates annual drought-related losses in the U.S. at $6–$8 billion, which is more than any other natural hazard. Congress enacted the Agricultural Risk Protection Act of 2000 to encourage the U.S. Department of Agriculture (USDA) Risk Management Agency (RMA) and farmers to be more proactive in managing drought risk. Through the NSF’s Digital Government Program, the USDA RMA is working with the University of Nebraska–Lincoln Computer Science and Engineering Department, National Drought Mitigation Center (NDMC), and High Plains …

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New Technologies For Glycomic Analysis: Toward A Systematic Understanding Of The Glycome, John Rakus, Lara Mahal Jul 2015

New Technologies For Glycomic Analysis: Toward A Systematic Understanding Of The Glycome, John Rakus, Lara Mahal

John F. Rakus

Carbohydrates are the most difficult class of biological molecules to study by high-throughput methods owing to the chemical similarities between the constituent monosaccharide building blocks, template-less biosynthesis, and the lack of clearly identifiable consensus sequences for the glycan modification of cohorts of glycoproteins. These molecules are crucial for a wide variety of cellular processes ranging from cell-cell communication to immunity, and they are altered in disease states such as cancer and inflammation. Thus, there has been a dedicated effort to develop glycan analysis into a high-throughput analytical field termed glycomics. Herein we highlight major advances in applying separation, mass spectrometry, …

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Mir-30b/30d Regulation Of Galnac Transferases Enhances Invasion And Immunosuppression During Metastasis, Avital Gaziel-Sovran, Miguel Segura, Raffaella Di Micco, Mary Collins, Douglas Hanniford, Eleazar De Miera, John Rakus, John Dankert, Shulian Shang, Robert Kerbel, Nina Bhardwaj, Yongzhao Shao, Farbod Darvishian, Jiri Zavadil, Adrian Erlebacher, Lara Mahal, Iman Osman, Eva Hernando Jul 2015

Mir-30b/30d Regulation Of Galnac Transferases Enhances Invasion And Immunosuppression During Metastasis, Avital Gaziel-Sovran, Miguel Segura, Raffaella Di Micco, Mary Collins, Douglas Hanniford, Eleazar De Miera, John Rakus, John Dankert, Shulian Shang, Robert Kerbel, Nina Bhardwaj, Yongzhao Shao, Farbod Darvishian, Jiri Zavadil, Adrian Erlebacher, Lara Mahal, Iman Osman, Eva Hernando

John F. Rakus

To metastasize, a tumor cell must acquire abilities such as the capacity to colonize new tissue and evade immune surveillance. Recent evidence suggests that microRNAs can promote the evolution of malignant behaviors by regulating multiple targets. We performed a microRNA analysis of human melanoma, a highly invasive cancer, and found that miR-30b/30d upregulation correlates with stage, metastatic potential, shorter time to recurrence, and reduced overall survival. Ectopic expression of miR-30b/30d promoted the metastatic behavior of melanoma cells by directly targeting the GalNAc transferase GALNT7, resulted in increased synthesis of the immunosuppressive cytokine IL-10, and reduced immune cell activation and recruitment. …

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Understanding Organic Film Behavior On Alloy And Metal Oxides, Aparna Raman, Rosalynn Quiñones, Lisa Barriger, Rachel Eastman, Arash Parsi, Ellen Gawalt Jul 2015

Understanding Organic Film Behavior On Alloy And Metal Oxides, Aparna Raman, Rosalynn Quiñones, Lisa Barriger, Rachel Eastman, Arash Parsi, Ellen Gawalt

Rosalynn Quiñones-Fernández

Native oxide surfaces of stainless steel 316L and Nitinol alloys and their constituent metal oxides, namely nickel, chromium, molybdenum, manganese, iron, and titanium, were modified with long chain organic acids to better understand organic film formation. The adhesion and stability of films of octadecylphosphonic acid, octadecylhydroxamic acid, octadecylcarboxylic acid, and octadecylsulfonic acid on these substrates were examined in this study. The films formed on these surfaces were analyzed by diffuse reflectance infrared Fourier transform spectroscopy, contact angle goniometry, atomic force microscopy, and matrix-assisted laser desorption ionization mass spectrometry. The effect of the acidity of the organic moiety and substrate composition …

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Football Betting And The Efficient Market Hypothesis, Ravija Badarinathi, Ladd Kochman Jul 2015

Football Betting And The Efficient Market Hypothesis, Ravija Badarinathi, Ladd Kochman

Ladd Kochman

Three betting rules which had been nonrandomly profitable in both their initial application to the 1969-74 National Football League seasons and their replication during the years of 1975-81 were applied to all NFL games played between September 1984 and January 1994. One rule proved to be nonrandom and profitable for a third consecutive trial--a feat suggesting that bettors may be able to "beat the bookie" and, more broadly, that prices in competitive markets may not discount all available information in swift fashion.

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Geochronology Of Hemphillian-Blancan Aged Strata, Guanajuato, Mexico, And Implications For Timing Of The Great American Biotic Interchange, Bart Kowallis, John Flynn, Clarita Nunez, Oscar Carranza-Castaneda, Wade Miller, Carl Swisher, Everett Lindsay Jul 2015

Geochronology Of Hemphillian-Blancan Aged Strata, Guanajuato, Mexico, And Implications For Timing Of The Great American Biotic Interchange, Bart Kowallis, John Flynn, Clarita Nunez, Oscar Carranza-Castaneda, Wade Miller, Carl Swisher, Everett Lindsay

Bart J Kowallis

We present new geochronologic magnetostratigraphy, fission-track and 40Ar/39Ar radioisotopic dates, biostratigraphy)bdata constraining the age of three separate sequences and a composite section from Guanajuato, Mexico. Those data make this one of the most complete and precisely age-calibrated sequences in North America spanning the Hemphillian/Blancan North American Land Mammal “Age” (NALMA) boundary interval, and the data further constrain the timing and pattern of the Great American Biotic Interchange (GABI). In total, 196 samples (77 sites) were used to construct the magnetic polarity stratigraphies, with eight fission-track analyses and four new 40Ar/39Ar radioisotopic dates. The sections sampled are possibly latest Miocene to …

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