Experimental and Computational Studies of Cortical Neural Network Properties Through Signal Processing

NASA Astrophysics Data System (ADS)

Clawson, Wesley Patrick

Previous studies, both theoretical and experimental, of network level dynamics in the cerebral cortex show evidence for a statistical phenomenon called criticality; a phenomenon originally studied in the context of phase transitions in physical systems and that is associated with favorable information processing in the context of the brain. The focus of this thesis is to expand upon past results with new experimentation and modeling to show a relationship between criticality and the ability to detect and discriminate sensory input. A line of theoretical work predicts maximal sensory discrimination as a functional benefit of criticality, which can then be characterized using mutual information between sensory input, visual stimulus, and neural response,. The primary finding of our experiments in the visual cortex in turtles and neuronal network modeling confirms this theoretical prediction. We show that sensory discrimination is maximized when visual cortex operates near criticality. In addition to presenting this primary finding in detail, this thesis will also address our preliminary results on change-point-detection in experimentally measured cortical dynamics.

Book review: Physics of tsunamis

USGS Publications Warehouse

Geist, Eric L.

2017-01-01

“Physics of Tsunamis”, second edition, provides a comprehensive analytical treatment of the hydrodynamics associated with the tsunami generation process. The book consists of seven chapters covering 388 pages. Because the subject matter within each chapter is distinct, an abstract appears at the beginning and references appear at the end of each chapter, rather than at the end of the book. Various topics of tsunami physics are examined largely from a theoretical perspective, although there is little information on how the physical descriptions are applied in numerical models.“Physics of Tsunamis”, by B. W. Levin and M. A. Nosov, Second Edition, Springer, 2016; ISBN-10: 33-1933106X, ISBN-13: 978-331933-1065

Design of the iPlay study: systematic development of a physical activity injury prevention programme for primary school children.

PubMed

Collard, Dorine C M; Chinapaw, Mai J M; van Mechelen, Willem; Verhagen, Evert A L M

2009-01-01

Health benefits of physical activity in children are well known. However, a drawback is the risk of physical activity-related injuries. Children are at particular risk for these injuries, because of a high level of exposure. Because of the high prevalence of physical activity injuries and the negative short- and long-term consequences, prevention of these injuries in children is important. This article describes how we systematically developed a school-based physical activity injury prevention programme using the intervention mapping (IM) protocol. IM describes a process for developing theory- and evidence-based health promotion programmes. The development can be described in six steps: (i) perform a needs assessment; (ii) identify programme and performance objectives; (iii) select methods and strategies; (iv) develop programme; (v) adopt and implement; and (vi) evaluate. First, the results of the needs assessment showed the injury problem in children and the different risk factors for physical activity injuries. Based on the results of the needs assessment the main focus of the injury prevention programme was described. Second, the overall programme objective of the injury prevention programme was defined as reducing the incidence of lower extremity physical activity injuries. Third, theoretical methods and practical strategies were selected to accomplish a decrease in injury incidence. The theoretical methods used were active learning, providing cues and scenario-based risk information, and active processing of information. The practical strategy of the injury prevention programme was an 8-month course about injury prevention to be used in physical education classes in primary schools. Fourth, programme materials that were used in the injury prevention programme were developed, including newsletters for children and parents, posters, exercises to improve motor fitness, and an information website. Fifth, an implementation plan was designed in order to ensure that the prevention programme would be implemented, adopted and sustained over time. Finally, an evaluation plan was designed. The injury prevention programme is being evaluated in a cluster randomized controlled trial with more than 2200 children from 40 primary schools throughout the Netherlands. The IM process is a useful process for developing an injury prevention programme. Based on the steps of the IM we developed an 8-month injury prevention programme to be used in physical education classes of primary schools.

Transfer entropy in physical systems and the arrow of time

NASA Astrophysics Data System (ADS)

Spinney, Richard E.; Lizier, Joseph T.; Prokopenko, Mikhail

2016-08-01

Recent developments have cemented the realization that many concepts and quantities in thermodynamics and information theory are shared. In this paper, we consider a highly relevant quantity in information theory and complex systems, the transfer entropy, and explore its thermodynamic role by considering the implications of time reversal upon it. By doing so we highlight the role of information dynamics on the nuanced question of observer perspective within thermodynamics by relating the temporal irreversibility in the information dynamics to the configurational (or spatial) resolution of the thermodynamics. We then highlight its role in perhaps the most enduring paradox in modern physics, the manifestation of a (thermodynamic) arrow of time. We find that for systems that process information such as those undergoing feedback, a robust arrow of time can be formulated by considering both the apparent physical behavior which leads to conventional entropy production and the information dynamics which leads to a quantity we call the information theoretic arrow of time. We also offer an interpretation in terms of optimal encoding of observed physical behavior.

On the Correct Analysis of the Foundations of Theoretical Physics

NASA Astrophysics Data System (ADS)

Kalanov, Temur Z.

2007-04-01

The problem of truth in science -- the most urgent problem of our time -- is discussed. The correct theoretical analysis of the foundations of theoretical physics is proposed. The principle of the unity of formal logic and rational dialectics is a methodological basis of the analysis. The main result is as follows: the generally accepted foundations of theoretical physics (i.e. Newtonian mechanics, Maxwell electrodynamics, thermodynamics, statistical physics and physical kinetics, the theory of relativity, quantum mechanics) contain the set of logical errors. These errors are explained by existence of the global cause: the errors are a collateral and inevitable result of the inductive way of cognition of the Nature, i.e. result of movement from formation of separate concepts to formation of the system of concepts. Consequently, theoretical physics enters the greatest crisis. It means that physics as a science of phenomenon leaves the progress stage for a science of essence (information). Acknowledgment: The books ``Surprises in Theoretical Physics'' (1979) and ``More Surprises in Theoretical Physics'' (1991) by Sir Rudolf Peierls stimulated my 25-year work.

Ideals and Realities: Articulating Feminist Perspectives in Physical Education.

ERIC Educational Resources Information Center

Smeal, Georgia; And Others

1994-01-01

Information from feminist physical educators helps examine relationships between theoretical debates in feminism and feminist practice in secondary schools. The article discusses debates over equality, how theoretical struggles between feminists are handled in sport and physical education, and how calls for equality are understood as calls for…

S&MPO - An information system for ozone spectroscopy on the WEB

NASA Astrophysics Data System (ADS)

Babikov, Yurii L.; Mikhailenko, Semen N.; Barbe, Alain; Tyuterev, Vladimir G.

2014-09-01

Spectroscopy and Molecular Properties of Ozone ("S&MPO") is an Internet accessible information system devoted to high resolution spectroscopy of the ozone molecule, related properties and data sources. S&MPO contains information on original spectroscopic data (line positions, line intensities, energies, transition moments, spectroscopic parameters) recovered from comprehensive analyses and modeling of experimental spectra as well as associated software for data representation written in PHP Java Script, C++ and FORTRAN. The line-by-line list of vibration-rotation transitions and other information is organized as a relational database under control of MySQL database tools. The main S&MPO goal is to provide access to all available information on vibration-rotation molecular states and transitions under extended conditions based on extrapolations of laboratory measurements using validated theoretical models. Applications for the S&MPO may include: education/training in molecular physics, radiative processes, laser physics; spectroscopic applications (analysis, Fourier transform spectroscopy, atmospheric optics, optical standards, spectroscopic atlases); applications to environment studies and atmospheric physics (remote sensing); data supply for specific databases; and to photochemistry (laser excitation, multiphoton processes). The system is accessible via Internet on two sites: http://smpo.iao.ru and http://smpo.univ-reims.fr.

Dementia Grief: A Theoretical Model of a Unique Grief Experience

PubMed Central

Blandin, Kesstan; Pepin, Renee

2016-01-01

Previous literature reveals a high prevalence of grief in dementia caregivers before physical death of the person with dementia that is associated with stress, burden, and depression. To date, theoretical models and therapeutic interventions with grief in caregivers have not adequately considered the grief process, but instead have focused on grief as a symptom that manifests within the process of caregiving. The Dementia Grief Model explicates the unique process of pre-death grief in dementia caregivers. In this paper we introduce the Dementia Grief Model, describe the unique characteristics dementia grief, and present the psychological states associated with the process of dementia grief. The model explicates an iterative grief process involving three states – separation, liminality, and re-emergence – each with a dynamic mechanism that facilitates or hinders movement through the dementia grief process. Finally, we offer potential applied research questions informed by the model. PMID:25883036

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cuevas, F.A.; Curilef, S., E-mail: scurilef@ucn.cl; Plastino, A.R., E-mail: arplastino@ugr.es

The spread of a wave-packet (or its deformation) is a very important topic in quantum mechanics. Understanding this phenomenon is relevant in connection with the study of diverse physical systems. In this paper we apply various 'spreading measures' to characterize the evolution of an initially localized wave-packet in a tight-binding lattice, with special emphasis on information-theoretical measures. We investigate the behavior of both the probability distribution associated with the wave packet and the concomitant probability current. Complexity measures based upon Renyi entropies appear to be particularly good descriptors of the details of the delocalization process. - Highlights: > Spread ofmore » highly localized wave-packet in the tight-binding lattice. > Entropic and information-theoretical characterization is used to understand the delocalization. > The behavior of both the probability distribution and the concomitant probability current is investigated. > Renyi entropies appear to be good descriptors of the details of the delocalization process.« less

Physics Without Physics. The Power of Information-theoretical Principles

NASA Astrophysics Data System (ADS)

D'Ariano, Giacomo Mauro

2017-01-01

David Finkelstein was very fond of the new information-theoretic paradigm of physics advocated by John Archibald Wheeler and Richard Feynman. Only recently, however, the paradigm has concretely shown its full power, with the derivation of quantum theory (Chiribella et al., Phys. Rev. A 84:012311, 2011; D'Ariano et al., 2017) and of free quantum field theory (D'Ariano and Perinotti, Phys. Rev. A 90:062106, 2014; Bisio et al., Phys. Rev. A 88:032301, 2013; Bisio et al., Ann. Phys. 354:244, 2015; Bisio et al., Ann. Phys. 368:177, 2016) from informational principles. The paradigm has opened for the first time the possibility of avoiding physical primitives in the axioms of the physical theory, allowing a re-foundation of the whole physics over logically solid grounds. In addition to such methodological value, the new information-theoretic derivation of quantum field theory is particularly interesting for establishing a theoretical framework for quantum gravity, with the idea of obtaining gravity itself as emergent from the quantum information processing, as also suggested by the role played by information in the holographic principle (Susskind, J. Math. Phys. 36:6377, 1995; Bousso, Rev. Mod. Phys. 74:825, 2002). In this paper I review how free quantum field theory is derived without using mechanical primitives, including space-time, special relativity, Hamiltonians, and quantization rules. The theory is simply provided by the simplest quantum algorithm encompassing a countable set of quantum systems whose network of interactions satisfies the three following simple principles: homogeneity, locality, and isotropy. The inherent discrete nature of the informational derivation leads to an extension of quantum field theory in terms of a quantum cellular automata and quantum walks. A simple heuristic argument sets the scale to the Planck one, and the currently observed regime where discreteness is not visible is the so-called "relativistic regime" of small wavevectors, which holds for all energies ever tested (and even much larger), where the usual free quantum field theory is perfectly recovered. In the present quantum discrete theory Einstein relativity principle can be restated without using space-time in terms of invariance of the eigenvalue equation of the automaton/walk under change of representations. Distortions of the Poincaré group emerge at the Planck scale, whereas special relativity is perfectly recovered in the relativistic regime. Discreteness, on the other hand, has some plus compared to the continuum theory: 1) it contains it as a special regime; 2) it leads to some additional features with GR flavor: the existence of an upper bound for the particle mass (with physical interpretation as the Planck mass), and a global De Sitter invariance; 3) it provides its own physical standards for space, time, and mass within a purely mathematical adimensional context. The paper ends with the future perspectives of this project, and with an Appendix containing biographic notes about my friendship with David Finkelstein, to whom this paper is dedicated.

Toward an Integrated Gender-Linked Model of Aggression Subtypes in Early and Middle Childhood

ERIC Educational Resources Information Center

Ostrov, Jamie M.; Godleski, Stephanie A.

2010-01-01

An integrative model is proposed for understanding the development of physical and relational aggression in early and middle childhood. The central goal was to posit a new theoretical framework that expands on existing social-cognitive and gender schema models (i.e., Social Information-Processing Model of Children's Adjustment [N. R. Crick & K. A.…

Shannon information entropy in heavy-ion collisions

NASA Astrophysics Data System (ADS)

Ma, Chun-Wang; Ma, Yu-Gang

2018-03-01

The general idea of information entropy provided by C.E. Shannon "hangs over everything we do" and can be applied to a great variety of problems once the connection between a distribution and the quantities of interest is found. The Shannon information entropy essentially quantify the information of a quantity with its specific distribution, for which the information entropy based methods have been deeply developed in many scientific areas including physics. The dynamical properties of heavy-ion collisions (HICs) process make it difficult and complex to study the nuclear matter and its evolution, for which Shannon information entropy theory can provide new methods and observables to understand the physical phenomena both theoretically and experimentally. To better understand the processes of HICs, the main characteristics of typical models, including the quantum molecular dynamics models, thermodynamics models, and statistical models, etc., are briefly introduced. The typical applications of Shannon information theory in HICs are collected, which cover the chaotic behavior in branching process of hadron collisions, the liquid-gas phase transition in HICs, and the isobaric difference scaling phenomenon for intermediate mass fragments produced in HICs of neutron-rich systems. Even though the present applications in heavy-ion collision physics are still relatively simple, it would shed light on key questions we are seeking for. It is suggested to further develop the information entropy methods in nuclear reactions models, as well as to develop new analysis methods to study the properties of nuclear matters in HICs, especially the evolution of dynamics system.

DNA as information: at the crossroads between biology, mathematics, physics and chemistry

PubMed Central

2016-01-01

On the one hand, biology, chemistry and also physics tell us how the process of translating the genetic information into life could possibly work, but we are still very far from a complete understanding of this process. On the other hand, mathematics and statistics give us methods to describe such natural systems—or parts of them—within a theoretical framework. Also, they provide us with hints and predictions that can be tested at the experimental level. Furthermore, there are peculiar aspects of the management of genetic information that are intimately related to information theory and communication theory. This theme issue is aimed at fostering the discussion on the problem of genetic coding and information through the presentation of different innovative points of view. The aim of the editors is to stimulate discussions and scientific exchange that will lead to new research on why and how life can exist from the point of view of the coding and decoding of genetic information. The present introduction represents the point of view of the editors on the main aspects that could be the subject of future scientific debate. PMID:26857674

Fundamental energy limits of SET-based Brownian NAND and half-adder circuits. Preliminary findings from a physical-information-theoretic methodology

NASA Astrophysics Data System (ADS)

Ercan, İlke; Suyabatmaz, Enes

2018-06-01

The saturation in the efficiency and performance scaling of conventional electronic technologies brings about the development of novel computational paradigms. Brownian circuits are among the promising alternatives that can exploit fluctuations to increase the efficiency of information processing in nanocomputing. A Brownian cellular automaton, where signals propagate randomly and are driven by local transition rules, can be made computationally universal by embedding arbitrary asynchronous circuits on it. One of the potential realizations of such circuits is via single electron tunneling (SET) devices since SET technology enable simulation of noise and fluctuations in a fashion similar to Brownian search. In this paper, we perform a physical-information-theoretic analysis on the efficiency limitations in a Brownian NAND and half-adder circuits implemented using SET technology. The method we employed here establishes a solid ground that enables studying computational and physical features of this emerging technology on an equal footing, and yield fundamental lower bounds that provide valuable insights into how far its efficiency can be improved in principle. In order to provide a basis for comparison, we also analyze a NAND gate and half-adder circuit implemented in complementary metal oxide semiconductor technology to show how the fundamental bound of the Brownian circuit compares against a conventional paradigm.

Transfer Entropy and Transient Limits of Computation

PubMed Central

Prokopenko, Mikhail; Lizier, Joseph T.

2014-01-01

Transfer entropy is a recently introduced information-theoretic measure quantifying directed statistical coherence between spatiotemporal processes, and is widely used in diverse fields ranging from finance to neuroscience. However, its relationships to fundamental limits of computation, such as Landauer's limit, remain unknown. Here we show that in order to increase transfer entropy (predictability) by one bit, heat flow must match or exceed Landauer's limit. Importantly, we generalise Landauer's limit to bi-directional information dynamics for non-equilibrium processes, revealing that the limit applies to prediction, in addition to retrodiction (information erasure). Furthermore, the results are related to negentropy, and to Bremermann's limit and the Bekenstein bound, producing, perhaps surprisingly, lower bounds on the computational deceleration and information loss incurred during an increase in predictability about the process. The identified relationships set new computational limits in terms of fundamental physical quantities, and establish transfer entropy as a central measure connecting information theory, thermodynamics and theory of computation. PMID:24953547

Nuclear Physics in High School: what are the previous knowledge?

NASA Astrophysics Data System (ADS)

Pombo, F. de O.

2017-11-01

Nuclear physics is a branch of physics that about a century occupies an important space in the theoretical, experimental and scientific fields. Currently, its relevance in application is concentrated in several areas such as energy production, diagnostic processes and medical treatment and nuclear bombs, high destructive power. Whereas, according to legal regulations, the teaching of physics must make the student competent in the understanding of the world and assuming the perspective of Paulo Freire (2011) that education is not done on the subject, but together with him, in dialogue with his point of departure, his prior knowledge, we established the general objective of raising students prior knowledge of the third year of high School at Nair Ferreira Neves school, in São Sebastião-SP, about nuclear physics. We concluded that the school has not fulfilled its role in relation to nuclear physics, because students have information from other means of information and these knowledge are stereotyped and mistaken, damaging the world's reading and exercising full citizenship.

Information physics fundamentals of nanophotonics.

PubMed

Naruse, Makoto; Tate, Naoya; Aono, Masashi; Ohtsu, Motoichi

2013-05-01

Nanophotonics has been extensively studied with the aim of unveiling and exploiting light-matter interactions that occur at a scale below the diffraction limit of light, and recent progress made in experimental technologies--both in nanomaterial fabrication and characterization--is driving further advancements in the field. From the viewpoint of information, on the other hand, novel architectures, design and analysis principles, and even novel computing paradigms should be considered so that we can fully benefit from the potential of nanophotonics. This paper examines the information physics aspects of nanophotonics. More specifically, we present some fundamental and emergent information properties that stem from optical excitation transfer mediated by optical near-field interactions and the hierarchical properties inherent in optical near-fields. We theoretically and experimentally investigate aspects such as unidirectional signal transfer, energy efficiency and networking effects, among others, and we present their basic theoretical formalisms and describe demonstrations of practical applications. A stochastic analysis of light-assisted material formation is also presented, where an information-based approach provides a deeper understanding of the phenomena involved, such as self-organization. Furthermore, the spatio-temporal dynamics of optical excitation transfer and its inherent stochastic attributes are utilized for solution searching, paving the way to a novel computing paradigm that exploits coherent and dissipative processes in nanophotonics.

Processes of behavior change and weight loss in a theory-based weight loss intervention program: a test of the process model for lifestyle behavior change.

PubMed

Gillison, Fiona; Stathi, Afroditi; Reddy, Prasuna; Perry, Rachel; Taylor, Gordon; Bennett, Paul; Dunbar, James; Greaves, Colin

2015-01-16

Process evaluation is important for improving theories of behavior change and behavioral intervention methods. The present study reports on the process outcomes of a pilot test of the theoretical model (the Process Model for Lifestyle Behavior Change; PMLBC) underpinning an evidence-informed, theory-driven, group-based intervention designed to promote healthy eating and physical activity for people with high cardiovascular risk. 108 people at high risk of diabetes or heart disease were randomized to a group-based weight management intervention targeting diet and physical activity plus usual care, or to usual care. The intervention comprised nine group based sessions designed to promote motivation, social support, self-regulation and understanding of the behavior change process. Weight loss, diet, physical activity and theoretically defined mediators of change were measured pre-intervention, and after four and 12 months. The intervention resulted in significant improvements in fiber intake (M between-group difference = 5.7 g/day, p < .001) but not fat consumption (-2.3 g/day, p = 0.13), that were predictive of weight loss at both four months (M between-group difference = -1.98 kg, p < .01; R(2) = 0.2, p < 0.005), and 12 months (M difference = -1.85 kg, p = 0.1; R(2) = 0.1, p < 0.01). The intervention was successful in improving the majority of specified mediators of behavior change, and the predicted mechanisms of change specified in the PMBLC were largely supported. Improvements in self-efficacy and understanding of the behavior change process were associated with engagement in coping planning and self-monitoring activities, and successful dietary change at four and 12 months. While participants reported improvements in motivational and social support variables, there was no effect of these, or of the intervention overall, on physical activity. The data broadly support the theoretical model for supporting some dietary changes, but not for physical activity. Systematic intervention design allowed us to identify where improvements to the intervention may be implemented to promote change in all proposed mediators. More work is needed to explore effective mechanisms within interventions to promote physical activity behavior.

Faithful communication Hamiltonian in photonic lattices

NASA Astrophysics Data System (ADS)

Bellec, Matthieu; Nikolopoulos, Georgios M.; Tzortzakis, Stelios

2012-11-01

Faithful communication is a necessary precondition for large scale all-optical networking and quantum information processing. Related theoretical investigations in different areas of physics have led to various proposals in which finite discrete lattices are used as channels for short-distance communication tasks. Here, in the framework of femtosecond-laser-written waveguide arrays, we present the first experimental realization of such a channel with judiciously engineered couplings.

Brain activity and cognition: a connection from thermodynamics and information theory.

PubMed

Collell, Guillem; Fauquet, Jordi

2015-01-01

The connection between brain and mind is an important scientific and philosophical question that we are still far from completely understanding. A crucial point to our work is noticing that thermodynamics provides a convenient framework to model brain activity, whereas cognition can be modeled in information-theoretical terms. In fact, several models have been proposed so far from both approaches. A second critical remark is the existence of deep theoretical connections between thermodynamics and information theory. In fact, some well-known authors claim that the laws of thermodynamics are nothing but principles in information theory. Unlike in physics or chemistry, a formalization of the relationship between information and energy is currently lacking in neuroscience. In this paper we propose a framework to connect physical brain and cognitive models by means of the theoretical connections between information theory and thermodynamics. Ultimately, this article aims at providing further insight on the formal relationship between cognition and neural activity.

Beyond Classical Information Theory: Advancing the Fundamentals for Improved Geophysical Prediction

NASA Astrophysics Data System (ADS)

Perdigão, R. A. P.; Pires, C. L.; Hall, J.; Bloeschl, G.

2016-12-01

Information Theory, in its original and quantum forms, has gradually made its way into various fields of science and engineering. From the very basic concepts of Information Entropy and Mutual Information to Transit Information, Interaction Information and respective partitioning into statistical synergy, redundancy and exclusivity, the overall theoretical foundations have matured as early as the mid XX century. In the Earth Sciences various interesting applications have been devised over the last few decades, such as the design of complex process networks of descriptive and/or inferential nature, wherein earth system processes are "nodes" and statistical relationships between them designed as information-theoretical "interactions". However, most applications still take the very early concepts along with their many caveats, especially in heavily non-Normal, non-linear and structurally changing scenarios. In order to overcome the traditional limitations of information theory and tackle elusive Earth System phenomena, we introduce a new suite of information dynamic methodologies towards a more physically consistent and information comprehensive framework. The methodological developments are then illustrated on a set of practical examples from geophysical fluid dynamics, where high-order nonlinear relationships elusive to the current non-linear information measures are aptly captured. In doing so, these advances increase the predictability of critical events such as the emergence of hyper-chaotic regimes in ocean-atmospheric dynamics and the occurrence of hydro-meteorological extremes.

Learning and Individual Differences: An Ability/Information - Processing Framework for Skill Acquisition

DTIC Science & Technology

1993-03-15

1992, Journal of Applied Psychology ).] This study represented an attempt to extend and test the Ackerman (1988) theory of the cognitive ability...both the physical state of the test -taker (e.g., time-of-day, arousal level; see Revelle, Humphreys, Simon, & Gilliland, 1980) and the psychological ...little consideration in the psychology of individual differences. -. Test directions almost never tell the examinee how to approach the task. Theoretically

DNA as information: at the crossroads between biology, mathematics, physics and chemistry.

PubMed

Cartwright, Julyan H E; Giannerini, Simone; González, Diego L

2016-03-13

On the one hand, biology, chemistry and also physics tell us how the process of translating the genetic information into life could possibly work, but we are still very far from a complete understanding of this process. On the other hand, mathematics and statistics give us methods to describe such natural systems-or parts of them-within a theoretical framework. Also, they provide us with hints and predictions that can be tested at the experimental level. Furthermore, there are peculiar aspects of the management of genetic information that are intimately related to information theory and communication theory. This theme issue is aimed at fostering the discussion on the problem of genetic coding and information through the presentation of different innovative points of view. The aim of the editors is to stimulate discussions and scientific exchange that will lead to new research on why and how life can exist from the point of view of the coding and decoding of genetic information. The present introduction represents the point of view of the editors on the main aspects that could be the subject of future scientific debate. © 2016 The Author(s).

Multiscale Granger causality

NASA Astrophysics Data System (ADS)

Faes, Luca; Nollo, Giandomenico; Stramaglia, Sebastiano; Marinazzo, Daniele

2017-10-01

In the study of complex physical and biological systems represented by multivariate stochastic processes, an issue of great relevance is the description of the system dynamics spanning multiple temporal scales. While methods to assess the dynamic complexity of individual processes at different time scales are well established, multiscale analysis of directed interactions has never been formalized theoretically, and empirical evaluations are complicated by practical issues such as filtering and downsampling. Here we extend the very popular measure of Granger causality (GC), a prominent tool for assessing directed lagged interactions between joint processes, to quantify information transfer across multiple time scales. We show that the multiscale processing of a vector autoregressive (AR) process introduces a moving average (MA) component, and describe how to represent the resulting ARMA process using state space (SS) models and to combine the SS model parameters for computing exact GC values at arbitrarily large time scales. We exploit the theoretical formulation to identify peculiar features of multiscale GC in basic AR processes, and demonstrate with numerical simulations the much larger estimation accuracy of the SS approach compared to pure AR modeling of filtered and downsampled data. The improved computational reliability is exploited to disclose meaningful multiscale patterns of information transfer between global temperature and carbon dioxide concentration time series, both in paleoclimate and in recent years.

How cells engulf: a review of theoretical approaches to phagocytosis

NASA Astrophysics Data System (ADS)

Richards, David M.; Endres, Robert G.

2017-12-01

Phagocytosis is a fascinating process whereby a cell surrounds and engulfs particles such as bacteria and dead cells. This is crucial both for single-cell organisms (as a way of acquiring nutrients) and as part of the immune system (to destroy foreign invaders). This whole process is hugely complex and involves multiple coordinated events such as membrane remodelling, receptor motion, cytoskeleton reorganisation and intracellular signalling. Because of this, phagocytosis is an excellent system for theoretical study, benefiting from biophysical approaches combined with mathematical modelling. Here, we review these theoretical approaches and discuss the recent mathematical and computational models, including models based on receptors, models focusing on the forces involved, and models employing energetic considerations. Along the way, we highlight a beautiful connection to the physics of phase transitions, consider the role of stochasticity, and examine links between phagocytosis and other types of endocytosis. We cover the recently discovered multistage nature of phagocytosis, showing that the size of the phagocytic cup grows in distinct stages, with an initial slow stage followed by a much quicker second stage starting around half engulfment. We also address the issue of target shape dependence, which is relevant to both pathogen infection and drug delivery, covering both one-dimensional and two-dimensional results. Throughout, we pay particular attention to recent experimental techniques that continue to inform the theoretical studies and provide a means to test model predictions. Finally, we discuss population models, connections to other biological processes, and how physics and modelling will continue to play a key role in future work in this area.

Brain activity and cognition: a connection from thermodynamics and information theory

PubMed Central

Collell, Guillem; Fauquet, Jordi

2015-01-01

The connection between brain and mind is an important scientific and philosophical question that we are still far from completely understanding. A crucial point to our work is noticing that thermodynamics provides a convenient framework to model brain activity, whereas cognition can be modeled in information-theoretical terms. In fact, several models have been proposed so far from both approaches. A second critical remark is the existence of deep theoretical connections between thermodynamics and information theory. In fact, some well-known authors claim that the laws of thermodynamics are nothing but principles in information theory. Unlike in physics or chemistry, a formalization of the relationship between information and energy is currently lacking in neuroscience. In this paper we propose a framework to connect physical brain and cognitive models by means of the theoretical connections between information theory and thermodynamics. Ultimately, this article aims at providing further insight on the formal relationship between cognition and neural activity. PMID:26136709

Novel physical constraints on implementation of computational processes

NASA Astrophysics Data System (ADS)

Wolpert, David; Kolchinsky, Artemy

Non-equilibrium statistical physics permits us to analyze computational processes, i.e., ways to drive a physical system such that its coarse-grained dynamics implements some desired map. It is now known how to implement any such desired computation without dissipating work, and what the minimal (dissipationless) work is that such a computation will require (the so-called generalized Landauer bound\\x9D). We consider how these analyses change if we impose realistic constraints on the computational process. First, we analyze how many degrees of freedom of the system must be controlled, in addition to the ones specifying the information-bearing degrees of freedom, in order to avoid dissipating work during a given computation, when local detailed balance holds. We analyze this issue for deterministic computations, deriving a state-space vs. speed trade-off, and use our results to motivate a measure of the complexity of a computation. Second, we consider computations that are implemented with logic circuits, in which only a small numbers of degrees of freedom are coupled at a time. We show that the way a computation is implemented using circuits affects its minimal work requirements, and relate these minimal work requirements to information-theoretic measures of complexity.

Perspective: Sloppiness and emergent theories in physics, biology, and beyond.

PubMed

Transtrum, Mark K; Machta, Benjamin B; Brown, Kevin S; Daniels, Bryan C; Myers, Christopher R; Sethna, James P

2015-07-07

Large scale models of physical phenomena demand the development of new statistical and computational tools in order to be effective. Many such models are "sloppy," i.e., exhibit behavior controlled by a relatively small number of parameter combinations. We review an information theoretic framework for analyzing sloppy models. This formalism is based on the Fisher information matrix, which is interpreted as a Riemannian metric on a parameterized space of models. Distance in this space is a measure of how distinguishable two models are based on their predictions. Sloppy model manifolds are bounded with a hierarchy of widths and extrinsic curvatures. The manifold boundary approximation can extract the simple, hidden theory from complicated sloppy models. We attribute the success of simple effective models in physics as likewise emerging from complicated processes exhibiting a low effective dimensionality. We discuss the ramifications and consequences of sloppy models for biochemistry and science more generally. We suggest that the reason our complex world is understandable is due to the same fundamental reason: simple theories of macroscopic behavior are hidden inside complicated microscopic processes.

T.D.S. spectroscopic databank for spherical tops: DOS version

NASA Astrophysics Data System (ADS)

Tyuterev, V. G.; Babikov, Yu. L.; Tashkun, S. A.; Perevalov, V. I.; Nikitin, A.; Champion, J.-P.; Wenger, C.; Pierre, C.; Pierre, G.; Hilico, J.-C.; Loete, M.

1994-10-01

T.D.S. (Traitement de Donnees Spectroscopiques or Tomsk-Dijon-Spectroscopy project) is a computer package concerned with high resolution spectroscopy of spherical top molecules like CH4, CF4, SiH4, SiF4, SnH4, GeH4, SF6, etc. T.D.S. contains information, fundamental spectroscopic data (energies, transition moments, spectroscopic constants) recovered from comprehensive modeling and simultaneous fitting of experimental spectra, and associated software written in C. The T.D.S. goal is to provide an access to all available information on vibration-rotation molecular states and transitions including various spectroscopic processes (Stark, Raman, etc.) under extended conditions based on extrapolations of laboratory measurements using validated theoretical models. Applications for T.D.S. may include: education/training in molecular physics, quantum chemistry, laser physics; spectroscopic applications (analysis, laser spectroscopy, atmospheric optics, optical standards, spectroscopic atlases); applications to environment studies and atmospheric physics (remote sensing); data supply for specific databases; and to photochemistry (laser excitation, multiphoton processes). The reported DOS-version is designed for IBM and compatible personal computers.

Special issue on coherent states: mathematical and physical aspects Special issue on coherent states: mathematical and physical aspects

NASA Astrophysics Data System (ADS)

Twareque Ali, Syed; Antoine, Jean-Pierre; Bagarello, Fabio; Gazeau, Jean-Pierre

2011-07-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to coherent states. The motivation behind this special issue is to gather in a single comprehensive volume the main aspects (past and present), latest developments, different viewpoints and directions being followed in this multidisciplinary field. Given the impressive development of the field in the past two decades, the topicality of such a volume can hardly be overemphasized. We strongly believe that such a special issue could become a particularly valuable reference for the broad scientific community working in mathematical and theoretical physics, as well as in signal processing and mathematics. Editorial policy The Guest Editors for this issue will be Syed Twareque Ali, Jean-Pierre Antoine, Fabio Bagarello and Jean-Pierre Gazeau. Potential topics include, but are not limited to, developments in the theory and applications of coherent states in: quantum optics, optomechanics, Bose-Einstein condensates quantum information, quantum measurement signal processing quantum gravity pseudo-Hermitian quantum mechanics supersymmetric quantum mechanics non-commutative quantum mechanics quantization theory harmonic and functional analysis operator theory Berezin-Toeplitz operators, PT-symmetric operators holomorphic representation theory, reproducing kernel spaces generalization of coherent states All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The deadline for contributed papers will be 31 October 2011. This deadline will allow the special issue to appear before the end of May 2012 There is a nominal page limit of 15 printed pages per contribution (invited review papers can be longer). For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on publishing your work in Journal of Physics A: Mathematical and Theoretical may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via authors.iop.org/, or by email to jphysa@iop.org, quoting `JPhysA Special issue on coherent states: mathematical and physical aspects'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Special issue on coherent states: mathematical and physical aspects Special issue on coherent states: mathematical and physical aspects

NASA Astrophysics Data System (ADS)

Twareque Ali, Syed; Antoine, Jean-Pierre; Bagarello, Fabio; Gazeau, Jean-Pierre

2011-06-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to coherent states. The motivation behind this special issue is to gather in a single comprehensive volume the main aspects (past and present), latest developments, different viewpoints and directions being followed in this multidisciplinary field. Given the impressive development of the field in the past two decades, the topicality of such a volume can hardly be overemphasized. We strongly believe that such a special issue could become a particularly valuable reference for the broad scientific community working in mathematical and theoretical physics, as well as in signal processing and mathematics. Editorial policy The Guest Editors for this issue will be Syed Twareque Ali, Jean-Pierre Antoine, Fabio Bagarello and Jean-Pierre Gazeau. Potential topics include, but are not limited to, developments in the theory and applications of coherent states in: quantum optics, optomechanics, Bose-Einstein condensates quantum information, quantum measurement signal processing quantum gravity pseudo-Hermitian quantum mechanics supersymmetric quantum mechanics non-commutative quantum mechanics quantization theory harmonic and functional analysis operator theory Berezin-Toeplitz operators, PT-symmetric operators holomorphic representation theory, reproducing kernel spaces generalization of coherent states All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The deadline for contributed papers will be 31 October 2011. This deadline will allow the special issue to appear before the end of May 2012 There is a nominal page limit of 15 printed pages per contribution (invited review papers can be longer). For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on publishing your work in Journal of Physics A: Mathematical and Theoretical may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via authors.iop.org/, or by email to jphysa@iop.org, quoting `JPhysA Special issue on coherent states: mathematical and physical aspects'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

The development of information processing biases in childhood anxiety: a review and exploration of its origins in parenting.

PubMed

Hadwin, Julie A; Garner, Matthew; Perez-Olivas, Gisela

2006-11-01

The aim of this paper is to explore parenting as one potential route through which information processing biases for threat develop in children. It reviews information processing biases in childhood anxiety in the context of theoretical models and empirical research in the adult anxiety literature. Specifically, it considers how adult models have been used and adapted to develop a theoretical framework with which to investigate information processing biases in children. The paper then considers research which specifically aims to understand the relationship between parenting and the development of information processing biases in children. It concludes that a clearer theoretical framework is required to understand the significance of information biases in childhood anxiety, as well as their origins in parenting.

Initiation Mechanism of Kinesin’s Neck Linker Docking Process

NASA Astrophysics Data System (ADS)

Geng, Yi-Zhao; Zhang, Hui; Lyu, Gang; Ji, Qing

2017-02-01

Not Available Supported by the National Natural Science Foundation of China under Grant Nos 11545014 and 11605038, and the Open Project Program of State Key Laboratory of Theoretical Physics of Institute of Theoretical Physics of Chinese Academy of Science under Grant No Y5KF211CJ1.

Evaluation development for a physical activity positive youth development program for girls.

PubMed

Ullrich-French, Sarah; Cole, Amy N; Montgomery, Anna K

2016-04-01

Girls on the Run (GOTR) is an after school program for girls in third through fifth grade which utilizes a physical activity based positive youth development curriculum that culminates with completing a 5K run. Unfortunately, there is little empirical data documenting GOTR participant changes that align with the curriculum and describe the evaluation process. Therefore, this study presents an evaluation of GOTR consisting of three main processes: curriculum content analysis and stakeholder focus groups (N=11) to identify key outcomes of the program; community-based participatory research to collaborate with program personnel to further identify important outcomes; and the design and pilot testing of an instrument (N=104) for assessing changes in the theoretically grounded outcomes over time. Findings demonstrated a positive collaborative process that led to important information to be used for an impact evaluation of Girls on the Run and for future evaluation development efforts for physical activity based positive youth development. Copyright © 2015 Elsevier Ltd. All rights reserved.

Generalized laws of thermodynamics in the presence of correlations.

PubMed

Bera, Manabendra N; Riera, Arnau; Lewenstein, Maciej; Winter, Andreas

2017-12-19

The laws of thermodynamics, despite their wide range of applicability, are known to break down when systems are correlated with their environments. Here we generalize thermodynamics to physical scenarios which allow presence of correlations, including those where strong correlations are present. We exploit the connection between information and physics, and introduce a consistent redefinition of heat dissipation by systematically accounting for the information flow from system to bath in terms of the conditional entropy. As a consequence, the formula for the Helmholtz free energy is accordingly modified. Such a remedy not only fixes the apparent violations of Landauer's erasure principle and the second law due to anomalous heat flows, but also leads to a generally valid reformulation of the laws of thermodynamics. In this information-theoretic approach, correlations between system and environment store work potential. Thus, in this view, the apparent anomalous heat flows are the refrigeration processes driven by such potentials.

Fundamental physics issues of multilevel logic in developing a parallel processor.

NASA Astrophysics Data System (ADS)

Bandyopadhyay, Anirban; Miki, Kazushi

2007-06-01

In the last century, On and Off physical switches, were equated with two decisions 0 and 1 to express every information in terms of binary digits and physically realize it in terms of switches connected in a circuit. Apart from memory-density increase significantly, more possible choices in particular space enables pattern-logic a reality, and manipulation of pattern would allow controlling logic, generating a new kind of processor. Neumann's computer is based on sequential logic, processing bits one by one. But as pattern-logic is generated on a surface, viewing whole pattern at a time is a truly parallel processing. Following Neumann's and Shannons fundamental thermodynamical approaches we have built compatible model based on series of single molecule based multibit logic systems of 4-12 bits in an UHV-STM. On their monolayer multilevel communication and pattern formation is experimentally verified. Furthermore, the developed intelligent monolayer is trained by Artificial Neural Network. Therefore fundamental weak interactions for the building of truly parallel processor are explored here physically and theoretically.

Information-theoretic metamodel of organizational evolution

NASA Astrophysics Data System (ADS)

Sepulveda, Alfredo

2011-12-01

Social organizations are abstractly modeled by holarchies---self-similar connected networks---and intelligent complex adaptive multiagent systems---large networks of autonomous reasoning agents interacting via scaled processes. However, little is known of how information shapes evolution in such organizations, a gap that can lead to misleading analytics. The research problem addressed in this study was the ineffective manner in which classical model-predict-control methods used in business analytics attempt to define organization evolution. The purpose of the study was to construct an effective metamodel for organization evolution based on a proposed complex adaptive structure---the info-holarchy. Theoretical foundations of this study were holarchies, complex adaptive systems, evolutionary theory, and quantum mechanics, among other recently developed physical and information theories. Research questions addressed how information evolution patterns gleamed from the study's inductive metamodel more aptly explained volatility in organization. In this study, a hybrid grounded theory based on abstract inductive extensions of information theories was utilized as the research methodology. An overarching heuristic metamodel was framed from the theoretical analysis of the properties of these extension theories and applied to business, neural, and computational entities. This metamodel resulted in the synthesis of a metaphor for, and generalization of organization evolution, serving as the recommended and appropriate analytical tool to view business dynamics for future applications. This study may manifest positive social change through a fundamental understanding of complexity in business from general information theories, resulting in more effective management.

Computational Thermomechanical Modelling of Early-Age Silicate Composites

NASA Astrophysics Data System (ADS)

Vala, J.; Št'astník, S.; Kozák, V.

2009-09-01

Strains and stresses in early-age silicate composites, widely used in civil engineering, especially in fresh concrete mixtures, in addition to those caused by exterior mechanical loads, are results of complicated non-deterministic physical and chemical processes. Their numerical prediction at the macro-scale level requires the non-trivial physical analysis based on the thermodynamic principles, making use of micro-structural information from both theoretical and experimental research. The paper introduces a computational model, based on a nonlinear system of macroscopic equations of evolution, supplied with certain effective material characteristics, coming from the micro-scale analysis, and sketches the algorithm for its numerical analysis.

Predicting physical activity and fruit and vegetable intake in adolescents: a test of the information, motivation, behavioral skills model.

PubMed

Kelly, Stephanie; Melnyk, Bernadette Mazurek; Belyea, Michael

2012-04-01

Most adolescents do not meet national recommendations regarding physical activity and/or the intake of fruits and vegetables. The purpose of this study was to explore whether variables in the information, motivation, behavioral skills (IMB) model of health promotion predicted physical activity and fruit and vegetable intake in 404 adolescents from 2 high schools in the Southwest United States using structural equation modeling (SEM). The SEM models included theoretical constructs, contextual variables, and moderators. The theoretical relationships in the IMB model were confirmed and were moderated by gender and race. Interventions that incorporate cognitive-behavioral skills building may be a key factor for promoting physical activity as well as fruit and vegetable intake in adolescents. Copyright © 2012 Wiley Periodicals, Inc.

α-induced reaction cross section measurements on 197Au

NASA Astrophysics Data System (ADS)

Szücs, Tamás; Gyürky, György; Halász, Zoltán; Kiss, Gábor Gy.; Fülöp, Zsolt

2018-01-01

The γ-process is responsible for creating the majority of the isotopes of heavier elements on the proton rich side of the valley of stability. The γ-process simulations fail to reproduce the measured solar system abundance of these isotopes. The problem can lie in the not well known astrophysical scenarios where the process takes place, or in the not sufficiently known nuclear physics input. To improve the latter part, α-induced reaction cross section measurements on 197Au were carried out at Atomki. With this dataset new experimental information will become available, which can be later used as validation of the theoretical cross section calculations used in the γ-process simulations.

Experimental realization of the Yang-Baxter Equation via NMR interferometry.

PubMed

Vind, F Anvari; Foerster, A; Oliveira, I S; Sarthour, R S; Soares-Pinto, D O; Souza, A M; Roditi, I

2016-02-10

The Yang-Baxter equation is an important tool in theoretical physics, with many applications in different domains that span from condensed matter to string theory. Recently, the interest on the equation has increased due to its connection to quantum information processing. It has been shown that the Yang-Baxter equation is closely related to quantum entanglement and quantum computation. Therefore, owing to the broad relevance of this equation, besides theoretical studies, it also became significant to pursue its experimental implementation. Here, we show an experimental realization of the Yang-Baxter equation and verify its validity through a Nuclear Magnetic Resonance (NMR) interferometric setup. Our experiment was performed on a liquid state Iodotrifluoroethylene sample which contains molecules with three qubits. We use Controlled-transfer gates that allow us to build a pseudo-pure state from which we are able to apply a quantum information protocol that implements the Yang-Baxter equation.

Finite-block-length analysis in classical and quantum information theory.

PubMed

Hayashi, Masahito

2017-01-01

Coding technology is used in several information processing tasks. In particular, when noise during transmission disturbs communications, coding technology is employed to protect the information. However, there are two types of coding technology: coding in classical information theory and coding in quantum information theory. Although the physical media used to transmit information ultimately obey quantum mechanics, we need to choose the type of coding depending on the kind of information device, classical or quantum, that is being used. In both branches of information theory, there are many elegant theoretical results under the ideal assumption that an infinitely large system is available. In a realistic situation, we need to account for finite size effects. The present paper reviews finite size effects in classical and quantum information theory with respect to various topics, including applied aspects.

Finite-block-length analysis in classical and quantum information theory

PubMed Central

HAYASHI, Masahito

2017-01-01

Coding technology is used in several information processing tasks. In particular, when noise during transmission disturbs communications, coding technology is employed to protect the information. However, there are two types of coding technology: coding in classical information theory and coding in quantum information theory. Although the physical media used to transmit information ultimately obey quantum mechanics, we need to choose the type of coding depending on the kind of information device, classical or quantum, that is being used. In both branches of information theory, there are many elegant theoretical results under the ideal assumption that an infinitely large system is available. In a realistic situation, we need to account for finite size effects. The present paper reviews finite size effects in classical and quantum information theory with respect to various topics, including applied aspects. PMID:28302962

The first dozen years of the history of ITEP Theoretical Physics Laboratory

NASA Astrophysics Data System (ADS)

Ioffe, B. L.

2013-01-01

The theoretical investigations at ITEP in the years 1945 - 1958 are reviewed. There are exposed the most important theoretical results, obtained in the following branches of physics: (1) the theory of nuclear reactors on thermal neutrons; (2) the hydrogen bomb project ("Tube" in USSR and "Classical Super" in USA); (3) radiation theory; (4) low temperature physics; (5) quantum electrodynamics and quantum field theories; (6) parity violation in weak interactions, the theory of β-decay and other weak processes; (7) strong interaction and nuclear physics. To the review are added the English translations of a few papers, originally published in Russian, but unknown (or almost unknown) to Western readers.

Evolution of Theoretical Perspectives in My Research

NASA Astrophysics Data System (ADS)

Otero, Valerie K.

2009-11-01

Over the past 10 years I have been using socio-cultural theoretical perspectives to understand how people learn physics in a highly interactive, inquiry-based physics course such as Physics and Everyday Thinking [1]. As a result of using various perspectives (e.g. Distributed Cognition and Vygotsky's Theory of Concept Formation), my understanding of how these perspectives can be useful for investigating students' learning processes has changed. In this paper, I illustrate changes in my thinking about the role of socio-cultural perspectives in understanding physics learning and describe elements of my thinking that have remained fairly stable. Finally, I will discuss pitfalls in the use of certain perspectives and discuss areas that need attention in theoretical development for PER.

Gamma rays from blazars

NASA Astrophysics Data System (ADS)

Tavecchio, Fabrizio

2017-01-01

Blazars are high-energy engines providing us natural laboratories to study particle acceleration, relativistic plasma processes, magnetic field dynamics, black hole physics. Key informations are provided by observations at high-energy (in particular by Fermi/LAT) and very-high energy (by Cherenkov telescopes). I give a short account of the current status of the field, with particular emphasis on the theoretical challenges connected to the observed ultra-fast variability events and to the emission of flat spectrum radio quasars in the very high energy band.

Security Analysis of Smart Grid Cyber Physical Infrastructures Using Modeling and Game Theoretic Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abercrombie, Robert K; Sheldon, Frederick T.

Cyber physical computing infrastructures typically consist of a number of sites are interconnected. Its operation critically depends both on cyber components and physical components. Both types of components are subject to attacks of different kinds and frequencies, which must be accounted for the initial provisioning and subsequent operation of the infrastructure via information security analysis. Information security analysis can be performed using game theory implemented in dynamic Agent Based Game Theoretic (ABGT) simulations. Such simulations can be verified with the results from game theory analysis and further used to explore larger scale, real world scenarios involving multiple attackers, defenders, andmore » information assets. We concentrated our analysis on the electric sector failure scenarios and impact analyses by the NESCOR Working Group Study, From the Section 5 electric sector representative failure scenarios; we extracted the four generic failure scenarios and grouped them into three specific threat categories (confidentiality, integrity, and availability) to the system. These specific failure scenarios serve as a demonstration of our simulation. The analysis using our ABGT simulation demonstrates how to model the electric sector functional domain using a set of rationalized game theoretic rules decomposed from the failure scenarios in terms of how those scenarios might impact the cyber physical infrastructure network with respect to CIA.« less

Engaging Students In Modeling Instruction for Introductory Physics

NASA Astrophysics Data System (ADS)

Brewe, Eric

2016-05-01

Teaching introductory physics is arguably one of the most important things that a physics department does. It is the primary way that students from other science disciplines engage with physics and it is the introduction to physics for majors. Modeling instruction is an active learning strategy for introductory physics built on the premise that science proceeds through the iterative process of model construction, development, deployment, and revision. We describe the role that participating in authentic modeling has in learning and then explore how students engage in this process in the classroom. In this presentation, we provide a theoretical background on models and modeling and describe how these theoretical elements are enacted in the introductory university physics classroom. We provide both quantitative and video data to link the development of a conceptual model to the design of the learning environment and to student outcomes. This work is supported in part by DUE #1140706.

Simulations of molecular self-assembled monolayers on surfaces: packing structures, formation processes and functions tuned by intermolecular and interfacial interactions.

PubMed

Wen, Jin; Li, Wei; Chen, Shuang; Ma, Jing

2016-08-17

Surfaces modified with a functional molecular monolayer are essential for the fabrication of nano-scale electronics or machines with novel physical, chemical, and/or biological properties. Theoretical simulation based on advanced quantum chemical and classical models is at present a necessary tool in the development, design, and understanding of the interfacial nanostructure. The nanoscale surface morphology, growth processes, and functions are controlled by not only the electronic structures (molecular energy levels, dipole moments, polarizabilities, and optical properties) of building units but also the subtle balance between intermolecular and interfacial interactions. The switchable surfaces are also constructed by introducing stimuli-responsive units like azobenzene derivatives. To bridge the gap between experiments and theoretical models, opportunities and challenges for future development of modelling of ferroelectricity, entropy, and chemical reactions of surface-supported monolayers are also addressed. Theoretical simulations will allow us to obtain important and detailed information about the structure and dynamics of monolayer modified interfaces, which will guide the rational design and optimization of dynamic interfaces to meet challenges of controlling optical, electrical, and biological functions.

How Physicists Made Stable Lévy Processes Physically Plausible

NASA Astrophysics Data System (ADS)

Schinckus, Christophe

2013-08-01

Stable Lévy processes have very interesting properties for describing the complex behaviour of non-equilibrium dissipative systems such as turbulence, anomalous diffusion or financial markets. However, although these processes better fit the empirical data, some of their statistical properties can raise several theoretical problems in empirical applications because they generate infinite variables. Econophysicists have developed statistical solutions to make these processes physically plausible. This paper presents a review of these analytical solutions (truncations) for stable Lévy processes and how econophysicists transformed them into data-driven processes. The evolution of these analytical solutions is presented as a progressive research programme provided by (econo)physicists for theoretical problems encountered in financial economics in the 1960s and the 1970s.

Approximate reversibility in the context of entropy gain, information gain, and complete positivity

NASA Astrophysics Data System (ADS)

Buscemi, Francesco; Das, Siddhartha; Wilde, Mark M.

2016-06-01

There are several inequalities in physics which limit how well we can process physical systems to achieve some intended goal, including the second law of thermodynamics, entropy bounds in quantum information theory, and the uncertainty principle of quantum mechanics. Recent results provide physically meaningful enhancements of these limiting statements, determining how well one can attempt to reverse an irreversible process. In this paper, we apply and extend these results to give strong enhancements to several entropy inequalities, having to do with entropy gain, information gain, entropic disturbance, and complete positivity of open quantum systems dynamics. Our first result is a remainder term for the entropy gain of a quantum channel. This result implies that a small increase in entropy under the action of a subunital channel is a witness to the fact that the channel's adjoint can be used as a recovery map to undo the action of the original channel. We apply this result to pure-loss, quantum-limited amplifier, and phase-insensitive quantum Gaussian channels, showing how a quantum-limited amplifier can serve as a recovery from a pure-loss channel and vice versa. Our second result regards the information gain of a quantum measurement, both without and with quantum side information. We find here that a small information gain implies that it is possible to undo the action of the original measurement if it is efficient. The result also has operational ramifications for the information-theoretic tasks known as measurement compression without and with quantum side information. Our third result shows that the loss of Holevo information caused by the action of a noisy channel on an input ensemble of quantum states is small if and only if the noise can be approximately corrected on average. We finally establish that the reduced dynamics of a system-environment interaction are approximately completely positive and trace preserving if and only if the data processing inequality holds approximately.

Physical studies of the planetary rings

NASA Technical Reports Server (NTRS)

Ip, W.-H.

1980-01-01

In this review paper, the physical properties of the Saturnian and Uranian rings as derived from ground-based observations are first discussed. Focus is then shifted to the study of the orbital dynamics of the ring particles. Numerical simulations of the evolutionary history of a system of colliding particles in differential rotation together with theoretical modeling of the inelastic collision processes are surveyed. In anticipation of the information returned from in situ measurements by space probes, interactions of the planetary rings with the interplanetary meteoroids and planetary magnetospheres are briefly considered. Finally, models of planetary ring origin are examined. In this connection, some recent work on the satellite resonant perturbation effects on the ring structure are also touched upon.

The capacity to transmit classical information via black holes

NASA Astrophysics Data System (ADS)

Adami, Christoph; Ver Steeg, Greg

2013-03-01

One of the most vexing problems in theoretical physics is the relationship between quantum mechanics and gravity. According to an argument originally by Hawking, a black hole must destroy any information that is incident on it because the only radiation that a black hole releases during its evaporation (the Hawking radiation) is precisely thermal. Surprisingly, this claim has never been investigated within a quantum information-theoretic framework, where the black hole is treated as a quantum channel to transmit classical information. We calculate the capacity of the quantum black hole channel to transmit classical information (the Holevo capacity) within curved-space quantum field theory, and show that the information carried by late-time particles sent into a black hole can be recovered with arbitrary accuracy, from the signature left behind by the stimulated emission of radiation that must accompany any absorption event. We also show that this stimulated emission turns the black hole into an almost-optimal quantum cloning machine, where the violation of the no-cloning theorem is ensured by the noise provided by the Hawking radiation. Thus, rather than threatening the consistency of theoretical physics, Hawking radiation manages to save it instead.

Modeling and analyses for an extended car-following model accounting for drivers' situation awareness from cyber physical perspective

NASA Astrophysics Data System (ADS)

Chen, Dong; Sun, Dihua; Zhao, Min; Zhou, Tong; Cheng, Senlin

2018-07-01

In fact, driving process is a typical cyber physical process which couples tightly the cyber factor of traffic information with the physical components of the vehicles. Meanwhile, the drivers have situation awareness in driving process, which is not only ascribed to the current traffic states, but also extrapolates the changing trend. In this paper, an extended car-following model is proposed to account for drivers' situation awareness. The stability criterion of the proposed model is derived via linear stability analysis. The results show that the stable region of proposed model will be enlarged on the phase diagram compared with previous models. By employing the reductive perturbation method, the modified Korteweg de Vries (mKdV) equation is obtained. The kink-antikink soliton of mKdV equation reveals theoretically the evolution of traffic jams. Numerical simulations are conducted to verify the analytical results. Two typical traffic Scenarios are investigated. The simulation results demonstrate that drivers' situation awareness plays a key role in traffic flow oscillations and the congestion transition.

Toward theoretical understanding of the fertility preservation decision-making process: examining information processing among young women with cancer.

PubMed

Hershberger, Patricia E; Finnegan, Lorna; Altfeld, Susan; Lake, Sara; Hirshfeld-Cytron, Jennifer

2013-01-01

Young women with cancer now face the complex decision about whether to undergo fertility preservation. Yet little is known about how these women process information involved in making this decision. The purpose of this article is to expand theoretical understanding of the decision-making process by examining aspects of information processing among young women diagnosed with cancer. Using a grounded theory approach, 27 women with cancer participated in individual, semistructured interviews. Data were coded and analyzed using constant-comparison techniques that were guided by 5 dimensions within the Contemplate phase of the decision-making process framework. In the first dimension, young women acquired information primarily from clinicians and Internet sources. Experiential information, often obtained from peers, occurred in the second dimension. Preferences and values were constructed in the third dimension as women acquired factual, moral, and ethical information. Women desired tailored, personalized information that was specific to their situation in the fourth dimension; however, women struggled with communicating these needs to clinicians. In the fifth dimension, women offered detailed descriptions of clinician behaviors that enhance or impede decisional debriefing. Better understanding of theoretical underpinnings surrounding women's information processes can facilitate decision support and improve clinical care.

Learning Quantitative Sequence-Function Relationships from Massively Parallel Experiments

NASA Astrophysics Data System (ADS)

Atwal, Gurinder S.; Kinney, Justin B.

2016-03-01

A fundamental aspect of biological information processing is the ubiquity of sequence-function relationships—functions that map the sequence of DNA, RNA, or protein to a biochemically relevant activity. Most sequence-function relationships in biology are quantitative, but only recently have experimental techniques for effectively measuring these relationships been developed. The advent of such "massively parallel" experiments presents an exciting opportunity for the concepts and methods of statistical physics to inform the study of biological systems. After reviewing these recent experimental advances, we focus on the problem of how to infer parametric models of sequence-function relationships from the data produced by these experiments. Specifically, we retrace and extend recent theoretical work showing that inference based on mutual information, not the standard likelihood-based approach, is often necessary for accurately learning the parameters of these models. Closely connected with this result is the emergence of "diffeomorphic modes"—directions in parameter space that are far less constrained by data than likelihood-based inference would suggest. Analogous to Goldstone modes in physics, diffeomorphic modes arise from an arbitrarily broken symmetry of the inference problem. An analytically tractable model of a massively parallel experiment is then described, providing an explicit demonstration of these fundamental aspects of statistical inference. This paper concludes with an outlook on the theoretical and computational challenges currently facing studies of quantitative sequence-function relationships.

Dynamic Substrate for the Physical Encoding of Sensory Information in Bat Biosonar

NASA Astrophysics Data System (ADS)

Müller, Rolf; Gupta, Anupam K.; Zhu, Hongxiao; Pannala, Mittu; Gillani, Uzair S.; Fu, Yanqing; Caspers, Philip; Buck, John R.

2017-04-01

Horseshoe bats have dynamic biosonar systems with interfaces for ultrasonic emission (reception) that change shape while diffracting the outgoing (incoming) sound waves. An information-theoretic analysis based on numerical and physical prototypes shows that these shape changes add sensory information (mutual information between distant shape conformations <20 %), increase the number of resolvable directions of sound incidence, and improve the accuracy of direction finding. These results demonstrate that horseshoe bats have a highly effective substrate for dynamic encoding of sensory information.

Dynamic Substrate for the Physical Encoding of Sensory Information in Bat Biosonar.

PubMed

Müller, Rolf; Gupta, Anupam K; Zhu, Hongxiao; Pannala, Mittu; Gillani, Uzair S; Fu, Yanqing; Caspers, Philip; Buck, John R

2017-04-14

Horseshoe bats have dynamic biosonar systems with interfaces for ultrasonic emission (reception) that change shape while diffracting the outgoing (incoming) sound waves. An information-theoretic analysis based on numerical and physical prototypes shows that these shape changes add sensory information (mutual information between distant shape conformations <20%), increase the number of resolvable directions of sound incidence, and improve the accuracy of direction finding. These results demonstrate that horseshoe bats have a highly effective substrate for dynamic encoding of sensory information.

Analysis of entropy extraction efficiencies in random number generation systems

NASA Astrophysics Data System (ADS)

Wang, Chao; Wang, Shuang; Chen, Wei; Yin, Zhen-Qiang; Han, Zheng-Fu

2016-05-01

Random numbers (RNs) have applications in many areas: lottery games, gambling, computer simulation, and, most importantly, cryptography [N. Gisin et al., Rev. Mod. Phys. 74 (2002) 145]. In cryptography theory, the theoretical security of the system calls for high quality RNs. Therefore, developing methods for producing unpredictable RNs with adequate speed is an attractive topic. Early on, despite the lack of theoretical support, pseudo RNs generated by algorithmic methods performed well and satisfied reasonable statistical requirements. However, as implemented, those pseudorandom sequences were completely determined by mathematical formulas and initial seeds, which cannot introduce extra entropy or information. In these cases, “random” bits are generated that are not at all random. Physical random number generators (RNGs), which, in contrast to algorithmic methods, are based on unpredictable physical random phenomena, have attracted considerable research interest. However, the way that we extract random bits from those physical entropy sources has a large influence on the efficiency and performance of the system. In this manuscript, we will review and discuss several randomness extraction schemes that are based on radiation or photon arrival times. We analyze the robustness, post-processing requirements and, in particular, the extraction efficiency of those methods to aid in the construction of efficient, compact and robust physical RNG systems.

Organizational Dimensions of Innovative Practice: A Qualitative Investigation of the Processes Supporting Innovation Adoption in Outpatient Physical Therapy Practice.

PubMed

Sabus, Carla; Spake, Ellen

2018-01-01

The ability to innovate and adapt practice is a requirement of the progressive healthcare provider. Innovative practice by rehabilitation providers has largely been approached as personal professional development; this study extends that perspective by examining innovation uptake from the organizational level. The varied professions can be expected to have distinct qualities of innovation adoption that reflect professional norms, values, and expectations. The purpose of this qualitative study was to describe the organizational processes of innovation uptake in outpatient physical therapy practice. Through nomination, two outpatient, privately owned physical therapy clinics were identified as innovation practices. Eighteen physical therapists, three owners, and a manager participated in the study. The two clinics served as case studies within a grounded theory approach. Data were collected through observation, unstructured questioning, work flow analysis, focus group sessions, and artifact analysis. Data were analyzed and coded among the investigators. A theoretical model of the innovation adoption process in outpatient physical therapy practice was developed. Elements of the model included (1) change grounded in relationship-centered care, (2) clinic readiness to accept change, and (3) clinic adaptability and resilience. A social paradigm of innovation adoption informed through this research complements the concentration on personal professional development.

Validity of the mockwitness paradigm: testing the assumptions.

PubMed

McQuiston, Dawn E; Malpass, Roy S

2002-08-01

Mockwitness identifications are used to provide a quantitative measure of lineup fairness. Some theoretical and practical assumptions of this paradigm have not been studied in terms of mockwitnesses' decision processes and procedural variation (e.g., instructions, lineup presentation method), and the current experiment was conducted to empirically evaluate these assumptions. Four hundred and eighty mockwitnesses were given physical information about a culprit, received 1 of 4 variations of lineup instructions, and were asked to identify the culprit from either a fair or unfair sequential lineup containing 1 of 2 targets. Lineup bias estimates varied as a result of lineup fairness and the target presented. Mockwitnesses generally reported that the target's physical description was their main source of identifying information. Our findings support the use of mockwitness identifications as a useful technique for sequential lineup evaluation, but only for mockwitnesses who selected only 1 lineup member. Recommendations for the use of this evaluation procedure are discussed.

Models of Speed Discrimination

NASA Technical Reports Server (NTRS)

1997-01-01

The prime purpose of this project was to investigate various theoretical issues concerning the integration of information across visual space. To date, most of the research efforts in the study of the visual system seem to have been focused in two almost non-overlaping directions. One research focus has been the low level perception as studied by psychophysics. The other focus has been the study of high level vision exemplified by the study of object perception. Most of the effort in psychophysics has been devoted to the search for the fundamental "features" of perception. The general idea is that the most peripheral processes of the visual system decompose the input into features that are then used for classification and recognition. The experimental and theoretical focus has been on finding and describing these analyzers that decompose images into useful components. Various models are then compared to the physiological measurements performed on neurons in the sensory systems. In the study of higher level perception, the work has been focused on the representation of objects and on the connections between various physical effects and object perception. In this category we find the perception of 3D from a variety of physical measurements including motion, shading and other physical phenomena. With few exceptions, there seem to be very limited development of theories describing how the visual system might combine the output of the analyzers to form the representation of visual objects. Therefore, the processes underlying the integration of information over space represent critical aspects of vision system. The understanding of these processes will have implications on our expectations for the underlying physiological mechanisms, as well as for our models of the internal representation for visual percepts. In this project, we explored several mechanisms related to spatial summation, attention, and eye movements. The project comprised three components: 1. Modeling visual search for the detection of speed deviation. 2. Perception of moving objects. 3. Exploring the role of eye movements in various visual tasks.

A qualitative study analyzing access to physical rehabilitation for traffic accident victims with severe disability in Brazil.

PubMed

Sousa, Kelienny de Meneses; Oliveira, Wagner Ivan Fonsêca de; Melo, Laiza Oliveira Mendes de; Alves, Emanuel Augusto; Piuvezam, Grasiela; Gama, Zenewton André da Silva

2017-03-01

Purpose To identify access barriers to physical rehabilitation for traffic accident (TA) victims with severe disability and build a theoretical model to provide guidance towards the improvement of these services. Methods Qualitative research carried out in the city of Natal (Northeast Brazil), with semi-structured interviews with 120 subjects (19 key informer health professionals and 101 TA victims) identified in a database made available by the emergency hospital. The interviews were analyzed using Alceste software, version 4.9. Results The main barriers present in the interviews were: (1) related to services: bureaucratic administrative practises, low offer of rehabilitation services, insufficient information on rehabilitation, lack of guidelines that integrate hospital and ambulatory care and (2) related to patients: financial difficulties, functional limitations, geographic distance, little information on health, association with low education levels and disbelief in the system and in rehabilitation. Conclusion The numerous access barriers were presented in a theoretical model with causes related to organizational structure, processes of care, professionals and patients. This model must be tested by health policy-makers and managers to improve the quality of physical rehabilitation and avoid unnecessary prolongation of the suffering and disability experienced by TA survivors. Implications for rehabilitation Traffic accidents (TAs) are a global health dilemma that demands integrality of preventive actions, pre-hospital and hospital care and physical rehabilitation (PR). This study lays the foundation for improving access to PR for TA survivors, an issue of quality of care that results in preventable disabilities. The words of the patients interviewed reveal the suffering of victims, which is often invisible to society and given low priority by health policies that relegate PR to a second plan ahead of prevention and urgent care. A theoretical model of the causes of the problem of access to PR was built. The identified barriers are potentially preventable through the intervention of health policy-makers, managers, regulators and rehabilitation professionals, and by encouraging the participation of patients. Addressing timely access barriers involves the expansion of the supply of services and rehabilitation professionals, regulation and standardization of referencing practises and encouraging the provision of information to patients about continuity of care and their health needs.

Physical-layer encryption on the public internet: A stochastic approach to the Kish-Sethuraman cipher

NASA Astrophysics Data System (ADS)

Gunn, Lachlan J.; Chappell, James M.; Allison, Andrew; Abbott, Derek

2014-09-01

While information-theoretic security is often associated with the one-time pad and quantum key distribution, noisy transport media leave room for classical techniques and even covert operation. Transit times across the public internet exhibit a degree of randomness, and cannot be determined noiselessly by an eavesdropper. We demonstrate the use of these measurements for information-theoretically secure communication over the public internet.

EPR Studies of Spin-Spin Exchange Processes: A Physical Chemistry Experiment.

ERIC Educational Resources Information Center

Eastman, Michael P.

1982-01-01

Theoretical background, experimental procedures, and analysis of experimental results are provided for an undergraduate physical chemistry experiment on electron paramagnetic resonance (EPR) linewidths. Source of line broadening observed in a spin-spin exchange process between radicals formed in aqueous solutions of potassium peroxylamine…

An Information Theoretic Analysis of Classification Sorting and Cognition by Ninth Grade Children within a Piagetian Setting.

ERIC Educational Resources Information Center

Dunlop, David Livingston

The purpose of this study was to use an information theoretic memory model to quantitatively investigate classification sorting and recall behaviors of various groups of students. The model provided theorems for the determination of information theoretic measures from which inferences concerning mental processing were made. The basic procedure…

Diffusion-controlled interface kinetics-inclusive system-theoretic propagation models for molecular communication systems

NASA Astrophysics Data System (ADS)

Chude-Okonkwo, Uche A. K.; Malekian, Reza; Maharaj, B. T.

2015-12-01

Inspired by biological systems, molecular communication has been proposed as a new communication paradigm that uses biochemical signals to transfer information from one nano device to another over a short distance. The biochemical nature of the information transfer process implies that for molecular communication purposes, the development of molecular channel models should take into consideration diffusion phenomenon as well as the physical/biochemical kinetic possibilities of the process. The physical and biochemical kinetics arise at the interfaces between the diffusion channel and the transmitter/receiver units. These interfaces are herein termed molecular antennas. In this paper, we present the deterministic propagation model of the molecular communication between an immobilized nanotransmitter and nanoreceiver, where the emission and reception kinetics are taken into consideration. Specifically, we derived closed-form system-theoretic models and expressions for configurations that represent different communication systems based on the type of molecular antennas used. The antennas considered are the nanopores at the transmitter and the surface receptor proteins/enzymes at the receiver. The developed models are simulated to show the influence of parameters such as the receiver radius, surface receptor protein/enzyme concentration, and various reaction rate constants. Results show that the effective receiver surface area and the rate constants are important to the system's output performance. Assuming high rate of catalysis, the analysis of the frequency behavior of the developed propagation channels in the form of transfer functions shows significant difference introduce by the inclusion of the molecular antennas into the diffusion-only model. It is also shown that for t > > 0 and with the information molecules' concentration greater than the Michaelis-Menten kinetic constant of the systems, the inclusion of surface receptors proteins and enzymes in the models makes the system act like a band-stop filter over an infinite frequency range.

Disclosing victimisation to healthcare professionals in Sweden: a constructivist grounded theory study of experiences among men exposed to interpersonal violence

PubMed Central

Brüggemann, Adrianus Jelmer; Swahnberg, Katarina

2016-01-01

Objective To develop a theoretical model concerning male victims' processes of disclosing experiences of victimisation to healthcare professionals in Sweden. Design Qualitative interview study. Setting Informants were recruited from the general population and a primary healthcare centre in Sweden. Participants Informants were recruited by means of theoretical sampling among respondents in a previous quantitative study. Eligible for this study were men reporting sexual, physical and/or emotional violence victimisation by any perpetrator and reporting that they either had talked to a healthcare provider about their victimisation or had wanted to do so. Method Constructivist grounded theory. 12 interviews were performed and saturation was reached after 9. Results Several factors influencing the process of disclosing victimisation can be recognised from previous studies concerning female victims, including shame, fear of negative consequences of disclosing, specifics of the patient–provider relationship and time constraints within the healthcare system. However, this study extends previous knowledge by identifying strong negative effects of adherence to masculinity norms for victimised men and healthcare professionals on the process of disclosing. It is also emphasised that the process of disclosing cannot be separated from other, even seemingly unrelated, circumstances in the men's lives. Conclusions The process of disclosing victimisation to healthcare professionals was a complex process involving the men's experiences of victimisation, adherence to gender norms, their life circumstances and the dynamics of the actual healthcare encounter. PMID:27324711

Information Design Theories

ERIC Educational Resources Information Center

Pettersson, Rune

2014-01-01

Information design has practical and theoretical components. As an academic discipline we may view information design as a combined discipline, a practical theory, or as a theoretical practice. So far information design has incorporated facts, influences, methods, practices, principles, processes, strategies, and tools from a large number of…

NLPIR: A Theoretical Framework for Applying Natural Language Processing to Information Retrieval.

ERIC Educational Resources Information Center

Zhou, Lina; Zhang, Dongsong

2003-01-01

Proposes a theoretical framework called NLPIR that integrates natural language processing (NLP) into information retrieval (IR) based on the assumption that there exists representation distance between queries and documents. Discusses problems in traditional keyword-based IR, including relevance, and describes some existing NLP techniques.…

Evaluating the Theoretical Content of Online Physical Activity Information for People with Multiple Sclerosis

PubMed Central

Baillie, Colin P.T.; Galaviz, Karla; Jarvis, Jocelyn W.; Latimer-Cheung, Amy E.

2015-01-01

Background: Physical activity can aid people with multiple sclerosis (MS) in managing symptoms and maintaining functional abilities. The Internet is a preferred source of physical activity information for people with MS and, therefore, a method for the dissemination of behavior change techniques. The purpose of this study was to examine the coverage and quality of physical activity behavior change techniques delivered on the Internet for adults with MS using Abraham and Michie's taxonomy of behavior change techniques. Methods: Using the taxonomy, 20 websites were coded for quality (ie, accuracy of information) and coverage (ie, completeness of information) of theoretical behavior change techniques. Results: Results indicated that most websites covered a mean of 8.05 (SD 3.86, range 3–16) techniques out of a possible 20. Only one of the techniques, provide information on behavior–health link and consequences, was delivered on all websites. The websites demonstrated low mean coverage and quality across all behavior change techniques, with means of 0.64 (SD 0.67) and 0.62 (SD 0.37) on a scale of 0 to 2, respectively. However, coverage and quality improved when websites were examined solely for the techniques that they covered, as opposed to all 20 techniques. Conclusions: This study, which examined quality and coverage of physical activity behavior change techniques described online for people with MS, illustrated that the dissemination of these techniques requires improvement. PMID:25892979

Complexity theory and physical unification: From microscopic to oscopic level

NASA Astrophysics Data System (ADS)

Pavlos, G. P.; Iliopoulos, A. C.; Karakatsanis, L. P.; Tsoutsouras, V. G.; Pavlos, E. G.

During the last two decades, low dimensional chaotic or self-organized criticality (SOC) processes have been observed by our group in many different physical systems such as space plasmas, the solar or the magnetospheric dynamics, the atmosphere, earthquakes, the brain activity as well as in informational systems. All these systems are complex systems living far from equilibrium with strong self-organization and phase transition character. The theoretical interpretation of these natural phenomena needs a deeper insight into the fundamentals of complexity theory. In this study, we try to give a synoptic description of complexity theory both at the microscopic and at the oscopic level of the physical reality. Also, we propose that the self-organization observed oscopically is a phenomenon that reveals the strong unifying character of the complex dynamics which includes thermodynamical and dynamical characteristics in all levels of the physical reality. From this point of view, oscopical deterministic and stochastic processes are closely related to the microscopical chaos and self-organization. In this study the scientific work of scientists such as Wilson, Nicolis, Prigogine, Hooft, Nottale, El Naschie, Castro, Tsallis, Chang and others is used for the development of a unified physical comprehension of complex dynamics from the microscopic to the oscopic level.

Framing curriculum discursively: theoretical perspectives on the experience of VCE physics

NASA Astrophysics Data System (ADS)

Hart, Christina

2002-10-01

The process of developing prescribed curricula has been subject to little empirical investigation, and there have been few attempts to develop theoretical frameworks for understanding the shape and content of particular subjects. This paper presents an account of the author's experience of developing a new course for school physics in the State of Victoria, Australia, at the end of the 1980s. The course was to represent a significant departure from traditional physics courses, and was intended to broaden participation and improve the quality of student learning. In the event the new course turned out to be very similar to traditional courses in Physics. The paper explores the reasons for this outcome. Some powerful discursive mechanisms are identified and some implications of post-structuralism for the theoretical understanding of curriculum are discussed.

Fundamental Physical Limits for the Size of Future Planetary Surface Exploration Systems

NASA Astrophysics Data System (ADS)

Andrews, F.; Hobbs, S. E.; Honstvet, I.; Snelling, M.

2004-04-01

With the current interest in the potential use of Nanotechnology for spacecraft, it becomes increasingly likely that environmental sensor probes, such as the "lab-on-a-chip" concept, will take advantage of this technology and become orders of magnitude smaller than current sensor systems. This paper begins to investigate how small these systems could theoretically become, and what are the governing laws and limiting factors that determine that minimum size. The investigation focuses on the three primary subsystems for a sensor network of this nature Sensing, Information Processing and Communication. In general, there are few fundamental physical laws that limit the size of the sensor system. Limits tend to be driven by factors other than the laws of physics. These include user requirements, such as the acceptable probability of error, and the potential external environment.

Toward theoretical understanding of the fertility preservation decision-making process: Examining information processing among young women with cancer

PubMed Central

Hershberger, Patricia E.; Finnegan, Lorna; Altfeld, Susan; Lake, Sara; Hirshfeld-Cytron, Jennifer

2014-01-01

Background Young women with cancer now face the complex decision about whether to undergo fertility preservation. Yet little is known about how these women process information involved in making this decision. Objective The purpose of this paper is to expand theoretical understanding of the decision-making process by examining aspects of information processing among young women diagnosed with cancer. Methods Using a grounded theory approach, 27 women with cancer participated in individual, semi-structured interviews. Data were coded and analyzed using constant-comparison techniques that were guided by five dimensions within the Contemplate phase of the decision-making process framework. Results In the first dimension, young women acquired information primarily from clinicians and Internet sources. Experiential information, often obtained from peers, occurred in the second dimension. Preferences and values were constructed in the third dimension as women acquired factual, moral, and ethical information. Women desired tailored, personalized information that was specific to their situation in the fourth dimension; however, women struggled with communicating these needs to clinicians. In the fifth dimension, women offered detailed descriptions of clinician behaviors that enhance or impede decisional debriefing. Conclusion Better understanding of theoretical underpinnings surrounding women’s information processes can facilitate decision support and improve clinical care. PMID:24552086

Fermilab Today

Science.gov Websites

Series - One West Speaker: Peter Cooper, Fermilab Title: CLFV Searches in Muons 2:30 p.m. Theoretical COFFEE BREAK - 2nd Flr X-Over 4 p.m. Joint Experimental-Theoretical Physics Seminar - One West Speaker vaccination information available online Sign-up for this season's flu shot is available online. The Fermilab

Theoretical aspects of cellular decision-making and information-processing.

PubMed

Kobayashi, Tetsuya J; Kamimura, Atsushi

2012-01-01

Microscopic biological processes have extraordinary complexity and variety at the sub-cellular, intra-cellular, and multi-cellular levels. In dealing with such complex phenomena, conceptual and theoretical frameworks are crucial, which enable us to understand seemingly different intra- and inter-cellular phenomena from unified viewpoints. Decision-making is one such concept that has attracted much attention recently. Since a number of cellular behavior can be regarded as processes to make specific actions in response to external stimuli, decision-making can cover and has been used to explain a broad range of different cellular phenomena [Balázsi et al. (Cell 144(6):910, 2011), Zeng et al. (Cell 141(4):682, 2010)]. Decision-making is also closely related to cellular information-processing because appropriate decisions cannot be made without exploiting the information that the external stimuli contain. Efficiency of information transduction and processing by intra-cellular networks determines the amount of information obtained, which in turn limits the efficiency of subsequent decision-making. Furthermore, information-processing itself can serve as another concept that is crucial for understanding of other biological processes than decision-making. In this work, we review recent theoretical developments on cellular decision-making and information-processing by focusing on the relation between these two concepts.

Concerted Creativity: Emergence in the Socio-(Im)Material and Intangible Practice of Making Music.

PubMed

Hvidtfeldt, Dan Lund

2018-06-01

The purpose of this article is to explore how the basic conception of 'emergence' informs the study of creativity as a socio-material practice. Initially, the article explicates how creative processes, products and performances involve not only tangible, but also intangible and social elements. Secondly, the theoretical conception of creativity as socio-material and the general philosophical notion of emergence are introduced. Inspired by the idea that a 'whole' is other than the sum of its 'parts' and by examples primarily from the world of music, the article argues that the relationship between subject and object - the main analytical focus of studies on creativity as a socio-material practice - is fundamentally embedded in an emergent process. The article concludes by highlighting how emergence theory acknowledges the performance or product as an intangible material for creative processes of musicians, and that studies of the socio-materiality of creative practices clearly involving tangible, intangible and social elements must refer to the emergent process through which the creative product or performance evolves meaning. The theoretical framework suggested is relevant for researchers interested in exploring how materials, social settings and physical environments are involved in creative processes.

The Strength of Chaos: Accurate Simulation of Resonant Electron Scattering by Many-Electron Ions and Atoms in the Presence of Quantum Chaos

DTIC Science & Technology

2017-01-20

September 2016 PI and Co-PI information: Igor Bray; I.Bray@curtin.edu.au; Curtin University; Department of Physics , Astronomy and Medical Radiation... astrophysics , fusion energy through to cancer imaging and therapy. During the last two decades there has been immense progress in the field of...Theoretical Physics Division, at the Los Alamos National Laboratory. Theory: The underlying theoretical approach to collisions that we use is known as the

XIII Modave Summer School in Mathematical Physics

NASA Astrophysics Data System (ADS)

2017-09-01

The Modave Summer School on Mathematical Physics is a yearly summer school in topics of theoretical physics. Various topics ranging from quantum gravity and cosmology to theoretical particle physics and string theory. The school takes place in Modave, a charming village in the Belgian Ardennes close to Huy. Modave School is organised by PhD students for PhD students, and this makes it rather unique. The courses are taught by Post-Docs or late PhD students, and they are all made of pedagogical, basic blackboard lectures about recent topics in theoretical physics. Participants and lecturers eat and sleep in the same place where the lectures are given. The absence of senior members, and the fact of spending day and night together in an isolated, peaceful place contribute to creating an informal atmosphere and facilitating interactions. Lectures of the thirteenth edition are centered around the following subjects: bulk reconstruction in AdS/CFT, twistor theory, AdS_2/CFT_1 and SYK, geometry and topology, and asymptotic charges.

Mesoscopic coherence in light scattering from cold, optically dense and disordered atomic systems

NASA Astrophysics Data System (ADS)

Kupriyanov, D. V.; Sokolov, I. M.; Havey, M. D.

2017-02-01

Coherent effects manifested in light scattering from cold, optically dense and disordered atomic systems are reviewed from a primarily theoretical point of view. Development of the basic theoretical tools is then elaborated through several physical atomic physics based processes which have been at least partly explored experimentally. These include illustrations drawn from the coherent backscattering effect, random lasing in atomic gases, quantum memories and light-atoms interface assisted by the light trapping mechanism. Current understanding and challenges associated with the transition to high atomic densities and cooperativity in the scattering process are also discussed in some detail.

What Motivates Young Adults to Talk About Physical Activity on Social Network Sites?

PubMed Central

Campo, Shelly; Yang, Jingzhen; Eckler, Petya; Snetselaar, Linda; Janz, Kathleen; Leary, Emily

2017-01-01

Background Electronic word-of-mouth on social network sites has been used successfully in marketing. In social marketing, electronic word-of-mouth about products as health behaviors has the potential to be more effective and reach more young adults than health education through traditional mass media. However, little is known about what motivates people to actively initiate electronic word-of-mouth about health behaviors on their personal pages or profiles on social network sites, thus potentially reaching all their contacts on those sites. Objective This study filled the gap by applying a marketing theoretical model to explore the factors associated with electronic word-of-mouth on social network sites about leisure-time physical activity. Methods A Web survey link was sent to undergraduate students at one of the Midwestern universities and 439 of them completed the survey. Results The average age of the 439 participants was 19 years (SD=1 year, range: 18-24). Results suggested that emotional engagement with leisure-time physical activity (ie, affective involvement in leisure-time physical activity) predicted providing relevant opinions or information on social network sites. Social network site users who perceived stronger ties with all their contacts were more likely to provide and seek leisure-time physical activity opinions and information. People who provided leisure-time physical activity opinions and information were more likely to seek opinions and information, and people who forwarded information about leisure-time physical activity were more likely to chat about it. Conclusions This study shed light on the application of the electronic word-of-mouth theoretical framework in promoting health behaviors. The findings can also guide the development of future social marketing interventions using social network sites to promote leisure-time physical activity. PMID:28642215

Problem Solving in Physics: Undergraduates' Framing, Procedures, and Decision Making

NASA Astrophysics Data System (ADS)

Modir, Bahar

In this dissertation I will start with the broad research question of what does problem solving in upper division physics look like? My focus in this study is on students' problem solving in physics theory courses. Some mathematical formalisms are common across all physics core courses such as using the process of separation of variables, doing Taylor series, or using the orthogonality properties of mathematical functions to set terms equal to zero. However, there are slight differences in their use of these mathematical formalisms across different courses, possibly because of how students map different physical systems to these processes. Thus, my first main research question aims to answer how students perform these recurring processes across upper division physics courses. I break this broad question into three particular research questions: What knowledge pieces do students use to make connections between physics and procedural math? How do students use their knowledge pieces coherently to provide reasoning strategies in estimation problems? How do students look ahead into the problem to read the information out of the physical scenario to align their use of math in physics? Building on the previous body of the literature, I will use the theory family of Knowledge in Pieces and provide evidence to expand this theoretical foundation. I will compare my study with previous studies and provide suggestions on how to generalize these theory expansions for future use. My experimental data mostly come from video-based classroom data. Students in groups of 2-4 students solve in-class problems in quantum mechanics and electromagnetic fields 1 courses collaboratively. In addition, I will analyze clinical interviews to demonstrate how a single case study student plays an epistemic game to estimate the total energy in a hurricane. My second research question is more focused on a particular instructional context. How do students frame problem solving in quantum mechanics? I will lay out a new theoretical framework based in epistemic framing that separates the problem solving space into four frames divided along two axes. The first axis models students' framing in math and physics, expanded through the second axis of conceptual problem solving and algorithmic problem solving. I use this framework to show how students navigate problem solving. Lastly, I will use this developed framework to interpret existing difficulties in quantum mechanics.

Moral judgment as information processing: an integrative review.

PubMed

Guglielmo, Steve

2015-01-01

How do humans make moral judgments about others' behavior? This article reviews dominant models of moral judgment, organizing them within an overarching framework of information processing. This framework poses two distinct questions: (1) What input information guides moral judgments? and (2) What psychological processes generate these judgments? Information Models address the first question, identifying critical information elements (including causality, intentionality, and mental states) that shape moral judgments. A subclass of Biased Information Models holds that perceptions of these information elements are themselves driven by prior moral judgments. Processing Models address the second question, and existing models have focused on the relative contribution of intuitive versus deliberative processes. This review organizes existing moral judgment models within this framework and critically evaluates them on empirical and theoretical grounds; it then outlines a general integrative model grounded in information processing, and concludes with conceptual and methodological suggestions for future research. The information-processing framework provides a useful theoretical lens through which to organize extant and future work in the rapidly growing field of moral judgment.

Moral judgment as information processing: an integrative review

PubMed Central

Guglielmo, Steve

2015-01-01

How do humans make moral judgments about others’ behavior? This article reviews dominant models of moral judgment, organizing them within an overarching framework of information processing. This framework poses two distinct questions: (1) What input information guides moral judgments? and (2) What psychological processes generate these judgments? Information Models address the first question, identifying critical information elements (including causality, intentionality, and mental states) that shape moral judgments. A subclass of Biased Information Models holds that perceptions of these information elements are themselves driven by prior moral judgments. Processing Models address the second question, and existing models have focused on the relative contribution of intuitive versus deliberative processes. This review organizes existing moral judgment models within this framework and critically evaluates them on empirical and theoretical grounds; it then outlines a general integrative model grounded in information processing, and concludes with conceptual and methodological suggestions for future research. The information-processing framework provides a useful theoretical lens through which to organize extant and future work in the rapidly growing field of moral judgment. PMID:26579022

Preparing Prospective Physical Educators in Exercise Physiology.

ERIC Educational Resources Information Center

Bulger, Sean M.; Mohr, Derek J.; Carson, Linda M.; Robert, Darren L.; Wiegand, Robert L.

2000-01-01

Addresses the need for continued assessment of course content and instructional methods employed within physical education teacher education programs to deliver theoretical and applied information from the foundational subdiscipline of exercise physiology, describing an innovative course at one university (Exercise for School-Aged Children) which…

Breast cancer patients' narrative experiences about communication during the oncology care process: a qualitative study.

PubMed

Abt Sacks, A; Perestelo-Perez, L; Rodriguez-Martin, B; Cuellar-Pompa, L; Algara López, M; González Hernández, N; Serrano-Aguilar, P

2016-09-01

To analyse the perception about the information and communication received to evaluate oncologic care of breast cancer patients in Spain. Qualitative study based on conducting in-depth interviews. An inductive thematic analysis of the illness narratives was performed. Intentional theoretical sampling of 41 people diagnosed with breast cancer. The information provided during care process is assessed as appropriate, as it includes personalised skills focused on communication and considers organisational and contextual issues. In some cases, the information was considered partial, heterogeneous and at times contradictory, which revealed a lack of continuity. To provide and adequately cover information needs from the patient perspective, it is necessary to ensure access, both in its physical (material) and intellectual (comprehension) dimension, keeping in mind elements of social capital (social networks) and cultural capital (values, beliefs, non-verbal language) that facilitate or hinder access. The current state of transition to a horizontal model in the doctor-patient relationship, could account for the difficulties, deficits and contradictions in communication and information that breast cancer patients perceive in many contexts. © 2015 John Wiley & Sons Ltd.

Physical-chemical processes of diamond grinding

NASA Astrophysics Data System (ADS)

Lobanov, D. V.; Arhipov, P. V.; Yanyushkin, A. S.; Skeeba, V. Yu

2017-10-01

The article focuses on the relevance of the research into the problem of diamond abrasive metal-bonded tool performance loss with a view to enhancing the effectiveness of high-strength materials finishing processing. The article presents the results of theoretical and empirical studies of loading layer formation on the surface of diamond wheels during processing high-strength materials. The theoretical part deals with the physical and chemical processes at the contact area of the diamond wheel and work surface with the viewpoint of the electrochemical potentials equilibrium state. We defined dependencies for calculating the loading layer dimensions. The practical part of work centers on various electron-microscopic, spectral and X-ray diffraction studies of the metal-bonded wheel samples during diamond grinding. The analysis of the research results revealed the composition and structure of the loading layer. The validity of the theoretical data is confirmed by sufficient convergence of the calculated values with the results of empirical research. In order to reduce the intensity of loading and improve the cutting properties of metal-bonded diamond abrasive tools, it is recommended to use combined methods for more efficient processing of high-strength materials.

Information theoretic analysis of linear shift-invariant edge-detection operators

NASA Astrophysics Data System (ADS)

Jiang, Bo; Rahman, Zia-ur

2012-06-01

Generally, the designs of digital image processing algorithms and image gathering devices remain separate. Consequently, the performance of digital image processing algorithms is evaluated without taking into account the influences by the image gathering process. However, experiments show that the image gathering process has a profound impact on the performance of digital image processing and the quality of the resulting images. Huck et al. proposed one definitive theoretic analysis of visual communication channels, where the different parts, such as image gathering, processing, and display, are assessed in an integrated manner using Shannon's information theory. We perform an end-to-end information theory based system analysis to assess linear shift-invariant edge-detection algorithms. We evaluate the performance of the different algorithms as a function of the characteristics of the scene and the parameters, such as sampling, additive noise etc., that define the image gathering system. The edge-detection algorithm is regarded as having high performance only if the information rate from the scene to the edge image approaches its maximum possible. This goal can be achieved only by jointly optimizing all processes. Our information-theoretic assessment provides a new tool that allows us to compare different linear shift-invariant edge detectors in a common environment.

Combining Users’ Needs With Health Behavior Models in Designing an Internet- and Mobile-Based Intervention for Physical Activity in Cardiac Rehabilitation

PubMed Central

2014-01-01

Background Internet-based physical activity interventions have great potential in supporting patients in cardiac rehabilitation. Health behavior change theories and user input are identified as important contributors in the effectiveness of the interventions, but they are rarely combined in a systematic way in the design of the interventions. Objective The aim of this study is to identify the appropriate theoretical framework, along with the needs of the users of a physical activity intervention for cardiac rehabilitation, and to combine them into an effective Internet- and mobile-based intervention. Methods We explain the theoretical framework of the intervention in a narrative overview of the existing health behavior change literature as it applies to physical activity. We also conducted a focus group with 11 participants of a cardiac rehabilitation program and used thematic analysis to identify and analyze patterns of meaning in the transcribed data. Results We chose stage-based approaches, specifically the transtheoretical model and the health action process approach as our main framework for tailoring, supplemented with other theoretical concepts such as regulatory focus within the appropriate stages. From the thematic analysis of the focus group data, we identified seven themes: (1) social, (2) motivation, (3) integration into everyday life, (4) information, (5) planning, (6) monitoring and feedback, and (7) concerns and potential problems. The final design of the intervention was based on both the theoretical review and the user input, and it is explained in detail. Conclusions We applied a combination of health behavioral theory and user input in designing our intervention. We think this is a promising design approach with the potential to combine the high efficacy of theory-based interventions with the higher perceived usefulness of interventions designed according to user input. Trial Registration Clinicaltrials.gov NCT01223170; http://clinicaltrials.gov/show/NCT01223170 (Archived by WebCite at http://www.webcitation.org/6M5FqT9Q2). PMID:24413185

Thermodynamic Costs of Information Processing in Sensory Adaptation

PubMed Central

Sartori, Pablo; Granger, Léo; Lee, Chiu Fan; Horowitz, Jordan M.

2014-01-01

Biological sensory systems react to changes in their surroundings. They are characterized by fast response and slow adaptation to varying environmental cues. Insofar as sensory adaptive systems map environmental changes to changes of their internal degrees of freedom, they can be regarded as computational devices manipulating information. Landauer established that information is ultimately physical, and its manipulation subject to the entropic and energetic bounds of thermodynamics. Thus the fundamental costs of biological sensory adaptation can be elucidated by tracking how the information the system has about its environment is altered. These bounds are particularly relevant for small organisms, which unlike everyday computers, operate at very low energies. In this paper, we establish a general framework for the thermodynamics of information processing in sensing. With it, we quantify how during sensory adaptation information about the past is erased, while information about the present is gathered. This process produces entropy larger than the amount of old information erased and has an energetic cost bounded by the amount of new information written to memory. We apply these principles to the E. coli's chemotaxis pathway during binary ligand concentration changes. In this regime, we quantify the amount of information stored by each methyl group and show that receptors consume energy in the range of the information-theoretic minimum. Our work provides a basis for further inquiries into more complex phenomena, such as gradient sensing and frequency response. PMID:25503948

Quantum channels and memory effects

NASA Astrophysics Data System (ADS)

Caruso, Filippo; Giovannetti, Vittorio; Lupo, Cosmo; Mancini, Stefano

2014-10-01

Any physical process can be represented as a quantum channel mapping an initial state to a final state. Hence it can be characterized from the point of view of communication theory, i.e., in terms of its ability to transfer information. Quantum information provides a theoretical framework and the proper mathematical tools to accomplish this. In this context the notion of codes and communication capacities have been introduced by generalizing them from the classical Shannon theory of information transmission and error correction. The underlying assumption of this approach is to consider the channel not as acting on a single system, but on sequences of systems, which, when properly initialized allow one to overcome the noisy effects induced by the physical process under consideration. While most of the work produced so far has been focused on the case in which a given channel transformation acts identically and independently on the various elements of the sequence (memoryless configuration in jargon), correlated error models appear to be a more realistic way to approach the problem. A slightly different, yet conceptually related, notion of correlated errors applies to a single quantum system which evolves continuously in time under the influence of an external disturbance which acts on it in a non-Markovian fashion. This leads to the study of memory effects in quantum channels: a fertile ground where interesting novel phenomena emerge at the intersection of quantum information theory and other branches of physics. A survey is taken of the field of quantum channels theory while also embracing these specific and complex settings.

Toward a Stress Process Model of Children’s Exposure to Physical Family and Community Violence

PubMed Central

Brooks-Gunn, Jeanne

2011-01-01

Theoretically informed models are required to further the comprehensive understanding of children’s ETV. We draw on the stress process paradigm to forward an overall conceptual model of ETV (ETV) in childhood and adolescence. Around this conceptual model, we synthesize research in four dominant areas of the literature which are detailed but often disconnected including: (1) exposure to three forms of physical violence (e.g., child physical maltreatment, interparental violence, and community ETV); (2) the multilevel correlates and causes of ETV (e.g., neighborhood characteristics including concentrated disadvantage; family characteristics including socio-economic status and family stressors); (3) a range of consequences of ETV (e.g., internalizing and externalizing mental health problems, role transitions, and academic outcomes); and (4) multilevel and cross domain mediators and moderators of ETV influences (e.g., school and community factors, family social support, and individual coping resources). We highlight the range of interconnected processes through which violence exposures may influence children and suggest opportunities for prevention and intervention. We further identify needed future research on children’s ETV including coping resources as well as research on cumulative contributions of violence exposure, violence exposure modifications, curvilinearity, and timing of exposure. PMID:19434492

Enablers and barriers to physical activity in overweight and obese pregnant women: an analysis informed by the theoretical domains framework and COM-B model.

PubMed

Flannery, C; McHugh, S; Anaba, A E; Clifford, E; O'Riordan, M; Kenny, L C; McAuliffe, F M; Kearney, P M; Byrne, M

2018-05-21

Obesity during pregnancy is associated with increased risk of gestational diabetes mellitus (GDM) and other complications. Physical activity is a modifiable lifestyle factor that may help to prevent these complications but many women reduce their physical activity levels during pregnancy. Interventions targeting physical activity in pregnancy are on-going but few identify the underlying behaviour change mechanisms by which the intervention is expected to work. To enhance intervention effectiveness, recent tools in behavioural science such as the Theoretical Domains Framework (TDF) and COM-B model (capability, opportunity, motivation and behaviour) have been employed to understand behaviours for intervention development. Using these behaviour change methods, this study aimed to identify the enablers and barriers to physical activity in overweight and obese pregnant women. Semi-structured interviews were conducted with a purposive sample of overweight and obese women at different stages of pregnancy attending a public antenatal clinic in a large academic maternity hospital in Cork, Ireland. Interviews were recorded and transcribed into NVivo V.10 software. Data analysis followed the framework approach, drawing on the TDF and the COM-B model. Twenty one themes were identified and these mapped directly on to the COM-B model of behaviour change and ten of the TDF domains. Having the social opportunity to engage in physical activity was identified as an enabler; pregnant women suggested being active was easier when supported by their partners. Knowledge was a commonly reported barrier with women lacking information on safe activities during pregnancy and describing the information received from their midwife as 'limited'. Having the physical capability and physical opportunity to carry out physical activity were also identified as barriers; experiencing pain, a lack of time, having other children, and working prevented women from being active. A wide range of barriers and enablers were identified which influenced women's capability, motivation and opportunity to engage in physical activity with "knowledge" as the most commonly reported barrier. This study is a theoretical starting point in making a 'behavioural diagnoses' and the results will be used to inform the development of an intervention to increase physical activity levels among overweight and obese pregnant women.

Experimental test of Landauer’s principle in single-bit operations on nanomagnetic memory bits

PubMed Central

Hong, Jeongmin; Lambson, Brian; Dhuey, Scott; Bokor, Jeffrey

2016-01-01

Minimizing energy dissipation has emerged as the key challenge in continuing to scale the performance of digital computers. The question of whether there exists a fundamental lower limit to the energy required for digital operations is therefore of great interest. A well-known theoretical result put forward by Landauer states that any irreversible single-bit operation on a physical memory element in contact with a heat bath at a temperature T requires at least kBT ln(2) of heat be dissipated from the memory into the environment, where kB is the Boltzmann constant. We report an experimental investigation of the intrinsic energy loss of an adiabatic single-bit reset operation using nanoscale magnetic memory bits, by far the most ubiquitous digital storage technology in use today. Through sensitive, high-precision magnetometry measurements, we observed that the amount of dissipated energy in this process is consistent (within 2 SDs of experimental uncertainty) with the Landauer limit. This result reinforces the connection between “information thermodynamics” and physical systems and also provides a foundation for the development of practical information processing technologies that approach the fundamental limit of energy dissipation. The significance of the result includes insightful direction for future development of information technology. PMID:26998519

Information theoretic methods for image processing algorithm optimization

NASA Astrophysics Data System (ADS)

Prokushkin, Sergey F.; Galil, Erez

2015-01-01

Modern image processing pipelines (e.g., those used in digital cameras) are full of advanced, highly adaptive filters that often have a large number of tunable parameters (sometimes > 100). This makes the calibration procedure for these filters very complex, and the optimal results barely achievable in the manual calibration; thus an automated approach is a must. We will discuss an information theory based metric for evaluation of algorithm adaptive characteristics ("adaptivity criterion") using noise reduction algorithms as an example. The method allows finding an "orthogonal decomposition" of the filter parameter space into the "filter adaptivity" and "filter strength" directions. This metric can be used as a cost function in automatic filter optimization. Since it is a measure of a physical "information restoration" rather than perceived image quality, it helps to reduce the set of the filter parameters to a smaller subset that is easier for a human operator to tune and achieve a better subjective image quality. With appropriate adjustments, the criterion can be used for assessment of the whole imaging system (sensor plus post-processing).

Model-Based Reasoning in Upper-division Lab Courses

NASA Astrophysics Data System (ADS)

Lewandowski, Heather

2015-05-01

Modeling, which includes developing, testing, and refining models, is a central activity in physics. Well-known examples from AMO physics include everything from the Bohr model of the hydrogen atom to the Bose-Hubbard model of interacting bosons in a lattice. Modeling, while typically considered a theoretical activity, is most fully represented in the laboratory where measurements of real phenomena intersect with theoretical models, leading to refinement of models and experimental apparatus. However, experimental physicists use models in complex ways and the process is often not made explicit in physics laboratory courses. We have developed a framework to describe the modeling process in physics laboratory activities. The framework attempts to abstract and simplify the complex modeling process undertaken by expert experimentalists. The framework can be applied to understand typical processes such the modeling of the measurement tools, modeling ``black boxes,'' and signal processing. We demonstrate that the framework captures several important features of model-based reasoning in a way that can reveal common student difficulties in the lab and guide the development of curricula that emphasize modeling in the laboratory. We also use the framework to examine troubleshooting in the lab and guide students to effective methods and strategies.

Challenges and Requirements for the Application of Industry 4.0: A Special Insight with the Usage of Cyber-Physical System

NASA Astrophysics Data System (ADS)

Mueller, Egon; Chen, Xiao-Li; Riedel, Ralph

2017-09-01

Considered as a top priority of industrial development, Industry 4.0 (or Industrie 4.0 as the German version) has being highlighted as the pursuit of both academy and practice in companies. In this paper, based on the review of state of art and also the state of practice in different countries, shortcomings have been revealed as the lacking of applicable framework for the implementation of Industrie 4.0. Therefore, in order to shed some light on the knowledge of the details, a reference architecture is developed, where four perspectives namely manufacturing process, devices, software and engineering have been highlighted. Moreover, with a view on the importance of Cyber-Physical systems, the structure of Cyber-Physical System are established for the in-depth analysis. Further cases with the usage of Cyber-Physical System are also arranged, which attempts to provide some implications to match the theoretical findings together with the experience of companies. In general, results of this paper could be useful for the extending on the theoretical understanding of Industrie 4.0. Additionally, applied framework and prototypes based on the usage of Cyber-Physical Systems are also potential to help companies to design the layout of sensor nets, to achieve coordination and controlling of smart machines, to realize synchronous production with systematic structure, and to extend the usage of information and communication technologies to the maintenance scheduling.

Theoretical physics: Quarks fuse to release energy

NASA Astrophysics Data System (ADS)

Miller, Gerald A.

2017-11-01

In nuclear fusion, energy is produced by the rearrangement of protons and neutrons. The discovery of an analogue of this process involving particles called quarks has implications for both nuclear and particle physics. See Letter p.89

Judging nursing information on the WWW: a theoretical understanding.

PubMed

Cader, Raffik; Campbell, Steve; Watson, Don

2009-09-01

This paper is a report of a study of the judgement processes nurses use when evaluating World Wide Web information related to nursing practice. The World Wide Web has increased the global accessibility of online health information. However, the variable nature of the quality of World Wide Web information and its perceived level of reliability may lead to misinformation. This makes demands on healthcare professionals, and on nurses in particular, to ensure that health information of reliable quality is selected for use in practice. A grounded theory approach was adopted. Semi-structured interviews and focus groups were used to collect data, between 2004 and 2005, from 20 nurses undertaking a postqualification graduate course at a university and 13 nurses from a local hospital in the United Kingdom. A theoretical framework emerged that gave insight into the judgement process nurses use when evaluating World Wide Web information. Participants broke the judgement process down into specific tasks. In addition, they used tacit, process and propositional knowledge and intuition, quasi-rational cognition and analysis to undertake these tasks. World Wide Web information cues, time available and nurses' critical skills were influencing factors in their judgement process. Addressing the issue of quality and reliability associated with World Wide Web information is a global challenge. This theoretical framework could contribute towards meeting this challenge.

Disclosing victimisation to healthcare professionals in Sweden: a constructivist grounded theory study of experiences among men exposed to interpersonal violence.

PubMed

Simmons, Johanna; Brüggemann, Adrianus Jelmer; Swahnberg, Katarina

2016-06-20

To develop a theoretical model concerning male victims' processes of disclosing experiences of victimisation to healthcare professionals in Sweden. Qualitative interview study. Informants were recruited from the general population and a primary healthcare centre in Sweden. Informants were recruited by means of theoretical sampling among respondents in a previous quantitative study. Eligible for this study were men reporting sexual, physical and/or emotional violence victimisation by any perpetrator and reporting that they either had talked to a healthcare provider about their victimisation or had wanted to do so. Constructivist grounded theory. 12 interviews were performed and saturation was reached after 9. Several factors influencing the process of disclosing victimisation can be recognised from previous studies concerning female victims, including shame, fear of negative consequences of disclosing, specifics of the patient-provider relationship and time constraints within the healthcare system. However, this study extends previous knowledge by identifying strong negative effects of adherence to masculinity norms for victimised men and healthcare professionals on the process of disclosing. It is also emphasised that the process of disclosing cannot be separated from other, even seemingly unrelated, circumstances in the men's lives. The process of disclosing victimisation to healthcare professionals was a complex process involving the men's experiences of victimisation, adherence to gender norms, their life circumstances and the dynamics of the actual healthcare encounter. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Creativity and Quantum Physics: a New World View Unifying Current Theories of Creativity and Pointing Toward New Research Methodologies.

NASA Astrophysics Data System (ADS)

McCarthy, Kimberly Ann

1990-01-01

Divisions in definitions of creativity have centered primarily on the working definition of discontinuity and the inclusion of intrinsic features such as unconscious processing and intrinsic motivation and reinforcement. These differences generally result from Cohen's two world views underlying theories of creativity: Organismic, oriented toward holism; or mechanistic, oriented toward cause-effect reductionism. The quantum world view is proposed which theoretically and empirically unifies organismic and mechanistic elements of creativity. Based on Goswami's Idealistic Interpretation of quantum physics, the quantum view postulates the mind -brain as consisting of both classical and quantum structures and functions. The quantum domain accesses the transcendent order through coherent superpositions (a state of potentialities), while the classical domain performs the function of measuring apparatus through amplifying and recording the result of the collapse of the pure mental state. A theoretical experiment, based on the 1980 Marcel study of conscious and unconscious word-sense disambiguation, is conducted which compares the predictions of the quantum model with those of the 1975 Posner and Snyder Facilitation and Inhibition model. Each model agrees that while conscious access to information is limited, unconscious access is unlimited. However, each model differently defines the connection between these states: The Posner model postulates a central processing mechanism while the quantum model postulates a self-referential consciousness. Consequently, the two models predict differently. The strength of the quantum model lies in its ability to distinguish between classical and quantum definitions of discontinuity, as well as clarifying the function of consciousness, without added assumptions or ad-hoc analysis: Consciousness is an essential, valid feature of quantum mechanisms independent of the field of cognitive psychology. According to the quantum model, through a cycle of conscious and unconscious processing, various contexts are accessed, specifically, coherent superposition states and the removal of the subject-object dichotomy in unconscious processing. Coupled with a high tolerance for ambiguity, the individual has access not only to an increased quantity of information, but is exposed to this information in the absence of a self-referential or biased context, the result of which is an increase in creative behavior.

Use of information sources by family physicians: a literature survey.

PubMed Central

Verhoeven, A A; Boerma, E J; Meyboom-de Jong, B

1995-01-01

Analysis of the use of information sources by family physicians is important for both practical and theoretical reasons. First, analysis of the ways in which family physicians handle information may point to opportunities for improvement. Second, such efforts may lead to improvements in the methodology of literature research in general. This article reports on a survey of the literature on information use by family physicians. Eleven relevant research publications could be found. The data showed that family physicians used colleagues most often as information sources, followed by journals and books. This outcome corresponded with results in other professions. Several factors influenced the use of information sources by family physicians, including the physical, functional, and intellectual accessibility of the source; the physician's age; participation by the physician in research or education; the social context of the physician; practice characteristics; and the stage of the information-gathering process. The publications studied suggested ways to improve information gathering in the areas of computerization, education, library organization, and journal articles. PMID:7703946

Information-Processing Models and Curriculum Design

ERIC Educational Resources Information Center

Calfee, Robert C.

1970-01-01

"This paper consists of three sections--(a) the relation of theoretical analyses of learning to curriculum design, (b) the role of information-processing models in analyses of learning processes, and (c) selected examples of the application of information-processing models to curriculum design problems." (Author)

Sensing network for electromagnetic fields generated by seismic activities

NASA Astrophysics Data System (ADS)

Gershenzon, Naum I.; Bambakidis, Gust; Ternovskiy, Igor V.

2014-06-01

The sensors network is becoming prolific and play now increasingly more important role in acquiring and processing information. Cyber-Physical Systems are focusing on investigation of integrated systems that includes sensing, networking, and computations. The physics of the seismic measurement and electromagnetic field measurement requires special consideration how to design electromagnetic field measurement networks for both research and detection earthquakes and explosions along with the seismic measurement networks. In addition, the electromagnetic sensor network itself could be designed and deployed, as a research tool with great deal of flexibility, the placement of the measuring nodes must be design based on systematic analysis of the seismic-electromagnetic interaction. In this article, we review the observations of the co-seismic electromagnetic field generated by earthquakes and man-made sources such as vibrations and explosions. The theoretical investigation allows the distribution of sensor nodes to be optimized and could be used to support existing geological networks. The placement of sensor nodes have to be determined based on physics of electromagnetic field distribution above the ground level. The results of theoretical investigations of seismo-electromagnetic phenomena are considered in Section I. First, we compare the relative contribution of various types of mechano-electromagnetic mechanisms and then analyze in detail the calculation of electromagnetic fields generated by piezomagnetic and electrokinetic effects.

Experimental quantum simulations of many-body physics with trapped ions.

PubMed

Schneider, Ch; Porras, Diego; Schaetz, Tobias

2012-02-01

Direct experimental access to some of the most intriguing quantum phenomena is not granted due to the lack of precise control of the relevant parameters in their naturally intricate environment. Their simulation on conventional computers is impossible, since quantum behaviour arising with superposition states or entanglement is not efficiently translatable into the classical language. However, one could gain deeper insight into complex quantum dynamics by experimentally simulating the quantum behaviour of interest in another quantum system, where the relevant parameters and interactions can be controlled and robust effects detected sufficiently well. Systems of trapped ions provide unique control of both the internal (electronic) and external (motional) degrees of freedom. The mutual Coulomb interaction between the ions allows for large interaction strengths at comparatively large mutual ion distances enabling individual control and readout. Systems of trapped ions therefore exhibit a prominent system in several physical disciplines, for example, quantum information processing or metrology. Here, we will give an overview of different trapping techniques of ions as well as implementations for coherent manipulation of their quantum states and discuss the related theoretical basics. We then report on the experimental and theoretical progress in simulating quantum many-body physics with trapped ions and present current approaches for scaling up to more ions and more-dimensional systems.

The Learners' Experience of Variation: Following Students' Threads of Learning Physics in Computer Simulation Sessions

ERIC Educational Resources Information Center

Ingerman, Ake; Linder, Cedric; Marshall, Delia

2009-01-01

This article attempts to describe students' process of learning physics using the notion of experiencing variation as the basic mechanism for learning, and thus explores what variation, with respect to a particular object of learning, that students experience in their process of constituting understanding. Theoretically, the analysis relies on…

CONFERENCE DESCRIPTION Theory of Fusion Plasmas: Varenna-Lausanne International Workshop

NASA Astrophysics Data System (ADS)

Garbet, X.; Sauter, O.

2010-12-01

The Joint Varenna-Lausanne international workshop on Theory of Fusion Plasmas takes place every other year in a place particularly favourable for informal and in-depth discussions. Invited and contributed papers present state-of-the-art research in theoretical plasma physics, covering all domains relevant to fusion plasmas. This workshop always welcomes a fruitful mix of experienced researchers and students, to allow a better understanding of the key theoretical physics models and applications. Theoretical issues related to burning plasmas Anomalous Transport (Turbulence, Coherent Structures, Microinstabilities) RF Heating and Current Drive Macroinstabilities Plasma-Edge Physics and Divertors Fast particles instabilities Further details: http://Varenna-Lausanne.epfl.ch The conference is organized by: Centre de Recherches en Physique des Plasmas, Ecole Polytechnique Fédérale de Lausanne, Association EURATOM - Confédération Suisse 'Piero Caldirola' International Centre for the Promotion of Science and International School of Plasma Physics Istituto di Fisica del Plasma del CNR, Milano Editors: X Garbet (CEA, Cadarache, France) and O Sauter (CRPP-EPFL, Lausanne, Switzerland)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lizcano, D., E-mail: david.lizcano@udima.es, E-mail: mariaaurora.martinez@udima.es; Martínez, A. María, E-mail: david.lizcano@udima.es, E-mail: mariaaurora.martinez@udima.es

Edward Fredkin was an enthusiastic advocate of information-based theoretical physics, who, in the early 1980s, proposed a new theory of physics based on the idea that the universe is ultimately composed of software. According to Fredkin, reality should be considered as being composed not of particles, matter and forces or energy but of bits of data or information modified according to computational rules. Fredkin went on to demonstrate that, while energy is necessary for storing and retrieving information, it can be arbitrarily reduced in order to carry out any particular instance of information processing, and this operation does not havemore » a lower bound. This implies that it is information rather than matter or energy that should be considered at the ultimate fundamental constituent of reality. This possibility had already been suggested by other scientists. Norbert Wiener heralded a fundamental shift from energy to information and suggested that the universe was founded essentially on the transformation of information, not energy. However, Konrad Zuse was the first, back in 1967, to defend the idea that a digital computer is computing the universe. Richard P. Feynman showed this possibility in a similar light in his reflections on how information related to matter and energy. Other pioneering research on the theory of digital physics was published by Kantor in 1977 and more recently by Stephen Wolfram in 2002, who thereby joined the host of voices upholding that it is patterns of information, not matter and energy, that constitute the cornerstones of reality. In this paper, we introduce the use of knowledge management tools for the purpose of analysing this topic.« less

Bayesian coronal seismology

NASA Astrophysics Data System (ADS)

Arregui, Iñigo

2018-01-01

In contrast to the situation in a laboratory, the study of the solar atmosphere has to be pursued without direct access to the physical conditions of interest. Information is therefore incomplete and uncertain and inference methods need to be employed to diagnose the physical conditions and processes. One of such methods, solar atmospheric seismology, makes use of observed and theoretically predicted properties of waves to infer plasma and magnetic field properties. A recent development in solar atmospheric seismology consists in the use of inversion and model comparison methods based on Bayesian analysis. In this paper, the philosophy and methodology of Bayesian analysis are first explained. Then, we provide an account of what has been achieved so far from the application of these techniques to solar atmospheric seismology and a prospect of possible future extensions.

The Peculiar Status of the Second Law of Thermodynamics and the Quest for its Violation

NASA Astrophysics Data System (ADS)

D'Abramo, Germano

2012-11-01

Even though the second law of thermodynamics holds the supreme position among the laws of nature, as stated by many distinguished scientists, notably Eddington and Einstein, its position appears to be also quite peculiar. Given the atomic nature of matter, whose behaviour is well described by statistical physics, the second law could not hold unconditionally, but only statistically. It is not an absolute law. As a result of this, in the present paper we try to argue that we have not yet any truly cogent argument (known fundamental physical laws) to exclude its possible macroscopic violation. Even Landauer's information-theoretic principle seems to fall short of the initial expectations of being the fundamental `physical' reason of all Maxwell's demons failure. Here we propose a modified Szilard engine which operates without any steps in the process resembling the creation or destruction of information. We argue that the information-based exorcisms must be wrong, or at the very least superfluous, and that the real physical reason why such engines cannot work lies in the ubiquity of thermal fluctuations (and friction). We see in the above peculiar features the main motivation and rationale for pursuing exploratory research to challenge the second law, which is still ongoing and probably richer than ever. A quite thorough (and critical) description of some of these challenges is also given.

The peculiar status of the second law of thermodynamics and the quest for its violation

NASA Astrophysics Data System (ADS)

D'Abramo, Germano

2012-11-01

Even though the second law of thermodynamics holds the supreme position among the laws of nature, as stated by many distinguished scientists, notably Eddington and Einstein, its position appears to be also quite peculiar. Given the atomic nature of matter, whose behavior is well described by statistical physics, the second law could not hold unconditionally, but only statistically. It is not an absolute law. As a result of this, in the present paper we try to argue that we have not yet any truly cogent argument (known fundamental physical laws) to exclude its possible macroscopic violation. Even Landauer's information-theoretic principle seems to fall short of the initial expectations of being the fundamental 'physical' reason of all Maxwell's demons failure. Here we propose a modified Szilard engine which operates without any steps in the process resembling the creation or destruction of information. We argue that the information-based exorcisms must be wrong, or at the very least superfluous, and that the real physical reason why such engines cannot work lies in the ubiquity of thermal fluctuations (and friction). We see in the above peculiar features the main motivation and rationale for pursuing exploratory research to challenge the second law, which is still ongoing and probably richer than ever. A quite thorough (and critical) description of some of these challenges is also given.

Processing Motion: Using Code to Teach Newtonian Physics

NASA Astrophysics Data System (ADS)

Massey, M. Ryan

Prior to instruction, students often possess a common-sense view of motion, which is inconsistent with Newtonian physics. Effective physics lessons therefore involve conceptual change. To provide a theoretical explanation for concepts and how they change, the triangulation model brings together key attributes of prototypes, exemplars, theories, Bayesian learning, ontological categories, and the causal model theory. The triangulation model provides a theoretical rationale for why coding is a viable method for physics instruction. As an experiment, thirty-two adolescent students participated in summer coding academies to learn how to design Newtonian simulations. Conceptual and attitudinal data was collected using the Force Concept Inventory and the Colorado Learning Attitudes about Science Survey. Results suggest that coding is an effective means for teaching Newtonian physics.

Traditional and non-traditional approaches to the prediction of natural disasters

NASA Astrophysics Data System (ADS)

Sapunov, Valentin; Glazyrina, Tatiana

2016-04-01

Since the beginning of the 21st century the number of disasters in the world increased approximately two times. Damage from disasters cost an average of 230 billion dollars per year. Recently, the death toll in the disaster has reached 230,000 - 1 000,000 per year. Along with earthquakes, tsunamis, floods, increased the number of forest and steppe fires. These processes are not fully known global, geophysical and space reasons. Of great importance are perennial not until the end of the study of natural cycles. There is evidence that the state of the planet's surface affect processes in the Earth's core. Understanding the causes and prediction of the tragic events require an integrated effort based on the synthesis of various sciences as well as history which has knowledge about the disasters of the past. Factor that reduces the risk is constant monitoring, including both distant and contact methods. However, its possibility is limited. Firstly, due to the high cost of global, especially space monitoring. Secondly, due to the unpredictability of some processes. In December 2004, the countries of Southeast Asia hit by the tsunami. The death gotten 250 000 people. Animals in this cataclysm appeared to stay safety and advance left the danger zone. Animals are able to predict hazards having no materials predecessors. Participants nuclear tests show - a day before the explosion of the animals escape dangerous zone. This means that animals have the ability to predict the catastrophic events. The most important abiotic factor, the physical nature of which is still not clear is time. One of the scientists, who achieved some success in the study of time, was N.Kozyrev (1908-1983). He devoted his life to the study of the phenomenon of time and attempt to systematize the knowledge of him as a physical substance. Kozyrev in his theoretical calculations and experiments found the new field - the field of time (chrono-information). Through it can instantly and accurately transmit information in space and in time - from the past or the future, however, a diffuse form. The less significant by energy event is, the farther it is remote in time, the less accurate it becomes the transmitted information. Hence: 1. Create in addition to traditional monitoring system for monitoring the behavior of animals that can anticipate disasters natural and anthropogenic genesis based on the properties proscopy. 2. Carry out laboratory investigations of the physical properties of time based on the ideas Kozyrev and other Russian scientists. 3. Some known devices may be used to predict the existing, such as torsion balance. 4. To develop a theoretical framework of proscopy is actual field of both theoretical and applied science.

The entropic cost of quantum generalized measurements

NASA Astrophysics Data System (ADS)

Mancino, Luca; Sbroscia, Marco; Roccia, Emanuele; Gianani, Ilaria; Somma, Fabrizia; Mataloni, Paolo; Paternostro, Mauro; Barbieri, Marco

2018-03-01

Landauer's principle introduces a symmetry between computational and physical processes: erasure of information, a logically irreversible operation, must be underlain by an irreversible transformation dissipating energy. Monitoring micro- and nano-systems needs to enter into the energetic balance of their control; hence, finding the ultimate limits is instrumental to the development of future thermal machines operating at the quantum level. We report on the experimental investigation of a lower bound to the irreversible entropy associated to generalized quantum measurements on a quantum bit. We adopted a quantum photonics gate to implement a device interpolating from the weakly disturbing to the fully invasive and maximally informative regime. Our experiment prompted us to introduce a bound taking into account both the classical result of the measurement and the outcoming quantum state; unlike previous investigation, our entropic bound is based uniquely on measurable quantities. Our results highlight what insights the information-theoretic approach provides on building blocks of quantum information processors.

Span graphics display utilities handbook, first edition

NASA Technical Reports Server (NTRS)

Gallagher, D. L.; Green, J. L.; Newman, R.

1985-01-01

The Space Physics Analysis Network (SPAN) is a computer network connecting scientific institutions throughout the United States. This network provides an avenue for timely, correlative research between investigators, in a multidisciplinary approach to space physics studies. An objective in the development of SPAN is to make available direct and simplified procedures that scientists can use, without specialized training, to exchange information over the network. Information exchanges include raw and processes data, analysis programs, correspondence, documents, and graphite images. This handbook details procedures that can be used to exchange graphic images over SPAN. The intent is to periodically update this handbook to reflect the constantly changing facilities available on SPAN. The utilities described within reflect an earnest attempt to provide useful descriptions of working utilities that can be used to transfer graphic images across the network. Whether graphic images are representative of satellite servations or theoretical modeling and whether graphics images are of device dependent or independent type, the SPAN graphics display utilities handbook will be the users guide to graphic image exchange.

Physical and Chemical Processing in Flames

DTIC Science & Technology

2013-08-12

hydrogen-air flames. It order to evaluate the closeness of theoretical limit based on the Sivashinsky criterion with the experimental results we have... experimental H2-O2 results, and it is seen that the experimental transition regime does span around the neighborhood of the theoretical boundary, suggesting...for hydrogen–oxygen flames with the calculated theoretical boundary superimposed 13 In Fig. II-4 we plot the experimentally measured

A Comparison of Subjective and Objective Job Demands and Fit with Personal Resources as Predictors of Retirement Timing in a National U.S. Sample.

PubMed

Sonnega, Amanda; Helppie-McFall, Brooke; Hudomiet, Peter; Willis, Robert J; Fisher, Gwenith G

2017-12-19

Population aging and attendant pressures on public budgets have spurred considerable interest in understanding factors that influence retirement timing. A range of sociodemographic and economic characteristics predict both earlier and later retirement. Less is known about the role of job characteristics on the work choices of older workers. Researchers are increasingly using the subjective ratings of job characteristics available in the Health and Retirement Study in conjunction with more objective measures of job characteristics from the Occupational Information Network (O*NET) database. Employing a theoretically-informed model of job demands-personal resources fit, we constructed mismatch measures between resources and job demands (both subjectively and objectively assessed) in physical, emotional, and cognitive domains. When we matched comparable measures across the two data sources in the domains of physical, emotional, and cognitive job demands, we found that both sources of information held predictive power in relation to retirement timing. Physical and emotional but not cognitive mismatch were associated with earlier retirement. We discuss theoretical and practical implications of these findings and directions for future research.

Physical Complexity and Cognitive Evolution

NASA Astrophysics Data System (ADS)

Jedlicka, Peter

Our intuition tells us that there is a general trend in the evolution of nature, a trend towards greater complexity. However, there are several definitions of complexity and hence it is difficult to argue for or against the validity of this intuition. Christoph Adami has recently introduced a novel measure called physical complexity that assigns low complexity to both ordered and random systems and high complexity to those in between. Physical complexity measures the amount of information that an organism stores in its genome about the environment in which it evolves. The theory of physical complexity predicts that evolution increases the amount of `knowledge' an organism accumulates about its niche. It might be fruitful to generalize Adami's concept of complexity to the entire evolution (including the evolution of man). Physical complexity fits nicely into the philosophical framework of cognitive biology which considers biological evolution as a progressing process of accumulation of knowledge (as a gradual increase of epistemic complexity). According to this paradigm, evolution is a cognitive `ratchet' that pushes the organisms unidirectionally towards higher complexity. Dynamic environment continually creates problems to be solved. To survive in the environment means to solve the problem, and the solution is an embodied knowledge. Cognitive biology (as well as the theory of physical complexity) uses the concepts of information and entropy and views the evolution from both the information-theoretical and thermodynamical perspective. Concerning humans as conscious beings, it seems necessary to postulate an emergence of a new kind of knowledge - a self-aware and self-referential knowledge. Appearence of selfreflection in evolution indicates that the human brain reached a new qualitative level in the epistemic complexity.

The Theoretical Principles of the Organization of Information Systems.

ERIC Educational Resources Information Center

Kulikowski, Juliusz Lech

A survey of the theoretical problems connected with the organization and design of systems for processing and transmitting information is presented in this article. It gives a definition of Information Systems (IS) and classifies them from various points of view. It discusses briefly the most important aspects of the organization of IS, such as…

Modeling of information diffusion in Twitter-like social networks under information overload.

PubMed

Li, Pei; Li, Wei; Wang, Hui; Zhang, Xin

2014-01-01

Due to the existence of information overload in social networks, it becomes increasingly difficult for users to find useful information according to their interests. This paper takes Twitter-like social networks into account and proposes models to characterize the process of information diffusion under information overload. Users are classified into different types according to their in-degrees and out-degrees, and user behaviors are generalized into two categories: generating and forwarding. View scope is introduced to model the user information-processing capability under information overload, and the average number of times a message appears in view scopes after it is generated by a given type user is adopted to characterize the information diffusion efficiency, which is calculated theoretically. To verify the accuracy of theoretical analysis results, we conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly. These results are of importance to understand the diffusion dynamics in social networks, and this analysis framework can be extended to consider more realistic situations.

Modeling of Information Diffusion in Twitter-Like Social Networks under Information Overload

PubMed Central

Li, Wei

2014-01-01

Due to the existence of information overload in social networks, it becomes increasingly difficult for users to find useful information according to their interests. This paper takes Twitter-like social networks into account and proposes models to characterize the process of information diffusion under information overload. Users are classified into different types according to their in-degrees and out-degrees, and user behaviors are generalized into two categories: generating and forwarding. View scope is introduced to model the user information-processing capability under information overload, and the average number of times a message appears in view scopes after it is generated by a given type user is adopted to characterize the information diffusion efficiency, which is calculated theoretically. To verify the accuracy of theoretical analysis results, we conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly. These results are of importance to understand the diffusion dynamics in social networks, and this analysis framework can be extended to consider more realistic situations. PMID:24795541

Development of IR imaging system simulator

NASA Astrophysics Data System (ADS)

Xiang, Xinglang; He, Guojing; Dong, Weike; Dong, Lu

2017-02-01

To overcome the disadvantages of the tradition semi-physical simulation and injection simulation equipment in the performance evaluation of the infrared imaging system (IRIS), a low-cost and reconfigurable IRIS simulator, which can simulate the realistic physical process of infrared imaging, is proposed to test and evaluate the performance of the IRIS. According to the theoretical simulation framework and the theoretical models of the IRIS, the architecture of the IRIS simulator is constructed. The 3D scenes are generated and the infrared atmospheric transmission effects are simulated using OGRE technology in real-time on the computer. The physical effects of the IRIS are classified as the signal response characteristic, modulation transfer characteristic and noise characteristic, and they are simulated on the single-board signal processing platform based on the core processor FPGA in real-time using high-speed parallel computation method.

Using self-determination theory to promote adolescent girls' physical activity: Exploring the theoretical fidelity of the Bristol Girls Dance Project.

PubMed

Sebire, Simon J; Kesten, Joanna M; Edwards, Mark J; May, Thomas; Banfield, Kathryn; Tomkinson, Keeley; Blair, Peter S; Bird, Emma L; Powell, Jane E; Jago, Russell

2016-05-01

To report the theory-based process evaluation of the Bristol Girls' Dance Project, a cluster-randomised controlled trial to increase adolescent girls' physical activity. A mixed-method process evaluation of the intervention's self-determination theory components comprising lesson observations, post-intervention interviews and focus groups. Four intervention dance lessons per dance instructor were observed, audio recorded and rated to estimate the use of need-supportive teaching strategies. Intervention participants (n = 281) reported their dance instructors' provision of autonomy-support. Semi-structured interviews with the dance instructors (n = 10) explored fidelity to the theory and focus groups were conducted with participants (n = 59) in each school to explore their receipt of the intervention and views on the dance instructors' motivating style. Although instructors accepted the theory-based approach, intervention fidelity was variable. Relatedness support was the most commonly observed need-supportive teaching behaviour, provision of structure was moderate and autonomy-support was comparatively low. The qualitative findings identified how instructors supported competence and developed trusting relationships with participants. Fidelity was challenged where autonomy provision was limited to option choices rather than input into the pace or direction of lessons and where controlling teaching styles were adopted, often to manage disruptive behaviour. The successes and challenges to achieving theoretical fidelity in the Bristol Girls' Dance Project may help explain the intervention effects and can more broadly inform the design of theory-based complex interventions aimed at increasing young people's physical activity in after-school settings.

Using self-determination theory to promote adolescent girls' physical activity: Exploring the theoretical fidelity of the Bristol Girls Dance Project

PubMed Central

Sebire, Simon J.; Kesten, Joanna M.; Edwards, Mark J.; May, Thomas; Banfield, Kathryn; Tomkinson, Keeley; Blair, Peter S.; Bird, Emma L.; Powell, Jane E.; Jago, Russell

2016-01-01

Objectives To report the theory-based process evaluation of the Bristol Girls' Dance Project, a cluster-randomised controlled trial to increase adolescent girls' physical activity. Design A mixed-method process evaluation of the intervention's self-determination theory components comprising lesson observations, post-intervention interviews and focus groups. Method Four intervention dance lessons per dance instructor were observed, audio recorded and rated to estimate the use of need-supportive teaching strategies. Intervention participants (n = 281) reported their dance instructors' provision of autonomy-support. Semi-structured interviews with the dance instructors (n = 10) explored fidelity to the theory and focus groups were conducted with participants (n = 59) in each school to explore their receipt of the intervention and views on the dance instructors' motivating style. Results Although instructors accepted the theory-based approach, intervention fidelity was variable. Relatedness support was the most commonly observed need-supportive teaching behaviour, provision of structure was moderate and autonomy-support was comparatively low. The qualitative findings identified how instructors supported competence and developed trusting relationships with participants. Fidelity was challenged where autonomy provision was limited to option choices rather than input into the pace or direction of lessons and where controlling teaching styles were adopted, often to manage disruptive behaviour. Conclusion The successes and challenges to achieving theoretical fidelity in the Bristol Girls' Dance Project may help explain the intervention effects and can more broadly inform the design of theory-based complex interventions aimed at increasing young people's physical activity in after-school settings. PMID:27175102

Natural Language Processing.

ERIC Educational Resources Information Center

Chowdhury, Gobinda G.

2003-01-01

Discusses issues related to natural language processing, including theoretical developments; natural language understanding; tools and techniques; natural language text processing systems; abstracting; information extraction; information retrieval; interfaces; software; Internet, Web, and digital library applications; machine translation for…

Neurophysiological Factors in Human Information Processing Capacity

ERIC Educational Resources Information Center

Ramsey, Nick F.; Jansma, J. M.; Jager, G.; Van Raalten, T.; Kahn, R. S.

2004-01-01

What determines how well an individual can manage the complexity of information processing demands when several tasks have to be executed simultaneously? Various theoretical frameworks address the mechanisms of information processing and the changes that take place when processes become automated, and brain regions involved in various types of…

Experimental Rectification of Entropy Production by Maxwell's Demon in a Quantum System

NASA Astrophysics Data System (ADS)

Camati, Patrice A.; Peterson, John P. S.; Batalhão, Tiago B.; Micadei, Kaonan; Souza, Alexandre M.; Sarthour, Roberto S.; Oliveira, Ivan S.; Serra, Roberto M.

2016-12-01

Maxwell's demon explores the role of information in physical processes. Employing information about microscopic degrees of freedom, this "intelligent observer" is capable of compensating entropy production (or extracting work), apparently challenging the second law of thermodynamics. In a modern standpoint, it is regarded as a feedback control mechanism and the limits of thermodynamics are recast incorporating information-to-energy conversion. We derive a trade-off relation between information-theoretic quantities empowering the design of an efficient Maxwell's demon in a quantum system. The demon is experimentally implemented as a spin-1 /2 quantum memory that acquires information, and employs it to control the dynamics of another spin-1 /2 system, through a natural interaction. Noise and imperfections in this protocol are investigated by the assessment of its effectiveness. This realization provides experimental evidence that the irreversibility in a nonequilibrium dynamics can be mitigated by assessing microscopic information and applying a feed-forward strategy at the quantum scale.

Experimental Rectification of Entropy Production by Maxwell's Demon in a Quantum System.

PubMed

Camati, Patrice A; Peterson, John P S; Batalhão, Tiago B; Micadei, Kaonan; Souza, Alexandre M; Sarthour, Roberto S; Oliveira, Ivan S; Serra, Roberto M

2016-12-09

Maxwell's demon explores the role of information in physical processes. Employing information about microscopic degrees of freedom, this "intelligent observer" is capable of compensating entropy production (or extracting work), apparently challenging the second law of thermodynamics. In a modern standpoint, it is regarded as a feedback control mechanism and the limits of thermodynamics are recast incorporating information-to-energy conversion. We derive a trade-off relation between information-theoretic quantities empowering the design of an efficient Maxwell's demon in a quantum system. The demon is experimentally implemented as a spin-1/2 quantum memory that acquires information, and employs it to control the dynamics of another spin-1/2 system, through a natural interaction. Noise and imperfections in this protocol are investigated by the assessment of its effectiveness. This realization provides experimental evidence that the irreversibility in a nonequilibrium dynamics can be mitigated by assessing microscopic information and applying a feed-forward strategy at the quantum scale.

Using intervention mapping to promote the receipt of clinical preventive services among women with physical disabilities.

PubMed

Suzuki, Rie; Peterson, Jana J; Weatherby, Amanda V; Buckley, David I; Walsh, Emily S; Kailes, June Isaacson; Krahn, Gloria L

2012-01-01

This article describes the development of Promoting Access to Health Services (PATHS), an intervention to promote regular use of clinical preventive services by women with physical disabilities. The intervention was developed using intervention mapping (IM), a theory-based logical process that incorporates the six steps of assessment of need, preparation of matrices, selection of theoretical methods and strategies, program design, program implementation, and evaluation. The development process used methods and strategies aligned with the social cognitive theory and the health belief model. PATHS was adapted from the workbook Making Preventive Health Care Work for You, developed by a disability advocate, and was informed by participant input at five points: at inception through consultation by the workbook author, in conceptualization through a town hall meeting, in pilot testing with feedback, in revision of the curriculum through an advisory group, and in implementation by trainers with disabilities. The resulting PATHS program is a 90-min participatory small-group workshop, followed by structured telephone support for 6 months.

Thermalization and prethermalization in isolated quantum systems: a theoretical overview

NASA Astrophysics Data System (ADS)

Mori, Takashi; Ikeda, Tatsuhiko N.; Kaminishi, Eriko; Ueda, Masahito

2018-06-01

The approach to thermal equilibrium, or thermalization, in isolated quantum systems is among the most fundamental problems in statistical physics. Recent theoretical studies have revealed that thermalization in isolated quantum systems has several remarkable features, which emerge from quantum entanglement and are quite distinct from those in classical systems. Experimentally, well isolated and highly controllable ultracold quantum gases offer an ideal testbed to study the nonequilibrium dynamics in isolated quantum systems, promoting intensive recent theoretical endeavors on this fundamental subject. Besides thermalization, many isolated quantum systems show intriguing behavior in relaxation processes, especially prethermalization. Prethermalization occurs when there is a clear separation of relevant time scales and has several different physical origins depending on individual systems. In this review, we overview theoretical approaches to the problems of thermalization and prethermalization.

Halley's Comet Makes a Comeback.

ERIC Educational Resources Information Center

Glenn, William H.

1984-01-01

Presents information on Halley's Comet including its discovery, impact on history, planned investigations related to its 1986 return, where and when to make observations, and predicted calendar of events. Gives general information on comets such as physical structure, theoretical origin, and paths and provides an annotated reference list. (JM)

A General No-Cloning Theorem for an infinite Multiverse

NASA Astrophysics Data System (ADS)

Gauthier, Yvon

2013-10-01

In this paper, I formulate a general no-cloning theorem which covers the quantum-mechanical and the theoretical quantum information cases as well as the cosmological multiverse theory. However, the main argument is topological and does not involve the peculiar copier devices of the quantum-mechanical and information-theoretic approaches to the no-cloning thesis. It is shown that a combinatorial set-theoretic treatment of the mathematical and physical spacetime continuum in cosmological or quantum-mechanical terms forbids an infinite (countable or uncountable) number of exact copies of finite elements (states) in the uncountable multiverse cosmology. The historical background draws on ideas from Weyl to Conway and Kochen on the free will theorem in quantum mechanics.

International Conference on Vacuum Ultraviolet Radiation Physics, 8th, Lunds Universitet, Sweden, Aug. 4-8, 1986, Proceedings

NASA Technical Reports Server (NTRS)

Nilsson, Per-Olof (Editor); Nordgren, Joseph (Editor)

1987-01-01

The interactions of VUV radiation with solids are explored in reviews and reports of recent theoretical and experimental investigations from the fields of atomic and molecular physics, solid-state physics, and VUV instrumentation. Topics examined include photoabsorption and photoionization, multiphoton processes, plasma physics, VUV lasers, time-resolved spectroscopy, synchrotron radiation centers, solid-state spectroscopy, and dynamical processes involving localized levels. Consideration is given to the fundamental principles of photoemission, spin-polarized photoemission, inverse photoemission, semiconductors, organic materials, and adsorbates.

Topological Isomorphisms of Human Brain and Financial Market Networks

PubMed Central

Vértes, Petra E.; Nicol, Ruth M.; Chapman, Sandra C.; Watkins, Nicholas W.; Robertson, Duncan A.; Bullmore, Edward T.

2011-01-01

Although metaphorical and conceptual connections between the human brain and the financial markets have often been drawn, rigorous physical or mathematical underpinnings of this analogy remain largely unexplored. Here, we apply a statistical and graph theoretic approach to the study of two datasets – the time series of 90 stocks from the New York stock exchange over a 3-year period, and the fMRI-derived time series acquired from 90 brain regions over the course of a 10-min-long functional MRI scan of resting brain function in healthy volunteers. Despite the many obvious substantive differences between these two datasets, graphical analysis demonstrated striking commonalities in terms of global network topological properties. Both the human brain and the market networks were non-random, small-world, modular, hierarchical systems with fat-tailed degree distributions indicating the presence of highly connected hubs. These properties could not be trivially explained by the univariate time series statistics of stock price returns. This degree of topological isomorphism suggests that brains and markets can be regarded broadly as members of the same family of networks. The two systems, however, were not topologically identical. The financial market was more efficient and more modular – more highly optimized for information processing – than the brain networks; but also less robust to systemic disintegration as a result of hub deletion. We conclude that the conceptual connections between brains and markets are not merely metaphorical; rather these two information processing systems can be rigorously compared in the same mathematical language and turn out often to share important topological properties in common to some degree. There will be interesting scientific arbitrage opportunities in further work at the graph-theoretically mediated interface between systems neuroscience and the statistical physics of financial markets. PMID:22007161

What Motivates Young Adults to Talk About Physical Activity on Social Network Sites?

PubMed

Zhang, Ni; Campo, Shelly; Yang, Jingzhen; Eckler, Petya; Snetselaar, Linda; Janz, Kathleen; Leary, Emily

2017-06-22

Electronic word-of-mouth on social network sites has been used successfully in marketing. In social marketing, electronic word-of-mouth about products as health behaviors has the potential to be more effective and reach more young adults than health education through traditional mass media. However, little is known about what motivates people to actively initiate electronic word-of-mouth about health behaviors on their personal pages or profiles on social network sites, thus potentially reaching all their contacts on those sites. This study filled the gap by applying a marketing theoretical model to explore the factors associated with electronic word-of-mouth on social network sites about leisure-time physical activity. A Web survey link was sent to undergraduate students at one of the Midwestern universities and 439 of them completed the survey. The average age of the 439 participants was 19 years (SD=1 year, range: 18-24). Results suggested that emotional engagement with leisure-time physical activity (ie, affective involvement in leisure-time physical activity) predicted providing relevant opinions or information on social network sites. Social network site users who perceived stronger ties with all their contacts were more likely to provide and seek leisure-time physical activity opinions and information. People who provided leisure-time physical activity opinions and information were more likely to seek opinions and information, and people who forwarded information about leisure-time physical activity were more likely to chat about it. This study shed light on the application of the electronic word-of-mouth theoretical framework in promoting health behaviors. The findings can also guide the development of future social marketing interventions using social network sites to promote leisure-time physical activity. ©Ni Zhang, Shelly Campo, Jingzhen Yang, Petya Eckler, Linda Snetselaar, Kathleen Janz, Emily Leary. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 22.06.2017.

The information geometry of chaos

NASA Astrophysics Data System (ADS)

Cafaro, Carlo

2008-10-01

In this Thesis, we propose a new theoretical information-geometric framework (IGAC, Information Geometrodynamical Approach to Chaos) suitable to characterize chaotic dynamical behavior of arbitrary complex systems. First, the problem being investigated is defined; its motivation and relevance are discussed. The basic tools of information physics and the relevant mathematical tools employed in this work are introduced. The basic aspects of Entropic Dynamics (ED) are reviewed. ED is an information-constrained dynamics developed by Ariel Caticha to investigate the possibility that laws of physics---either classical or quantum---may emerge as macroscopic manifestations of underlying microscopic statistical structures. ED is of primary importance in our IGAC. The notion of chaos in classical and quantum physics is introduced. Special focus is devoted to the conventional Riemannian geometrodynamical approach to chaos (Jacobi geometrodynamics) and to the Zurek-Paz quantum chaos criterion of linear entropy growth. After presenting this background material, we show that the ED formalism is not purely an abstract mathematical framework, but is indeed a general theoretical scheme from which conventional Newtonian dynamics is obtained as a special limiting case. The major elements of our IGAC and the novel notion of information geometrodynamical entropy (IGE) are introduced by studying two "toy models". To illustrate the potential power of our IGAC, one application is presented. An information-geometric analogue of the Zurek-Paz quantum chaos criterion of linear entropy growth is suggested. Finally, concluding remarks emphasizing strengths and weak points of our approach are presented and possible further research directions are addressed. At this stage of its development, IGAC remains an ambitious unifying information-geometric theoretical construct for the study of chaotic dynamics with several unsolved problems. However, based on our recent findings, we believe it already provides an interesting, innovative and potentially powerful way to study and understand the very important and challenging problems of classical and quantum chaos.

Practice Evaluation Strategies Among Social Workers: Why an Evidence-Informed Dual-Process Theory Still Matters.

PubMed

Davis, Thomas D

2017-01-01

Practice evaluation strategies range in style from the formal-analytic tools of single-subject designs, rapid assessment instruments, algorithmic steps in evidence-informed practice, and computer software applications, to the informal-interactive tools of clinical supervision, consultation with colleagues, use of client feedback, and clinical experience. The purpose of this article is to provide practice researchers in social work with an evidence-informed theory that is capable of explaining both how and why social workers use practice evaluation strategies to self-monitor the effectiveness of their interventions in terms of client change. The author delineates the theoretical contours and consequences of what is called dual-process theory. Drawing on evidence-informed advances in the cognitive and social neurosciences, the author identifies among everyday social workers a theoretically stable, informal-interactive tool preference that is a cognitively necessary, sufficient, and stand-alone preference that requires neither the supplementation nor balance of formal-analytic tools. The author's delineation of dual-process theory represents a theoretical contribution in the century-old attempt to understand how and why social workers evaluate their practice the way they do.

Physical activity and individuals with spinal cord injury: accuracy and quality of information on the Internet.

PubMed

Jetha, Arif; Faulkner, Guy; Gorczynski, Paul; Arbour-Nicitopoulos, Kelly; Martin Ginis, Kathleen A

2011-04-01

A number of websites on the Internet promote health-enhancing behaviors among people with spinal cord injury (SCI). However, the information available is of unknown accuracy and quality. To examine the accuracy, quality, and targeting strategies used in online physical activity (PA) information aimed at people with SCI. A purposive sample of 30 frequently accessed websites for individuals with SCI that included PA information was examined. Websites were evaluated based on their descriptive characteristics, level of accuracy in relation to newly defined PA recommendations for people with SCI, technical and theoretical quality (i.e., use of behavioral theories) characteristics, and targeting strategies to promote PA among people with SCI. Descriptive statistics were utilized to illustrate the results of the evaluation. PA information was easily accessible, as rated by the number of clicks required to access information. Only 6 websites (20%) provided specific PA recommendations and these websites exhibited low accuracy. Technically, websites were of high quality with a mean score of 4.1 of a possible 6 points. In contrast, websites had a low level of theoretical quality, with 23 of the 30 websites (77%) scoring below 9 of a possible 14 points (i.e., 64% of a perfect score) for theoretical content. A majority of websites evaluated did not use cognitive (e.g., self-efficacy, self-talk, and perceived social norms) and behavioral (e.g., self-monitoring, motivational readiness, and realistic goal-setting) strategies in their messages. A majority (80%) of the evaluated websites customized information for persons with different injury levels and completeness. Less than half of the websites evaluated tailored PA information toward people at different stages of their injury rehabilitation (37%) or for their caregivers (30%). Accuracy and theoretical quality of PA information presented to people with SCI on the Internet may not be optimal. Websites should be improved to incorporate accepted PA recommendations and behavioral theory to better deliver health messages about PA. Copyright © 2011 Elsevier Inc. All rights reserved.

Spiked Models of Large Dimensional Random Matrices Applied to Wireless Communications and Array Signal Processing

DTIC Science & Technology

2013-12-14

population covariance matrix with application to array signal processing; and 5) a sample covariance matrix for which a CLT is studied on linear...Applications , (01 2012): 1150004. doi: Walid Hachem, Malika Kharouf, Jamal Najim, Jack W. Silverstein. A CLT FOR INFORMATION- THEORETIC STATISTICS...for Multi-source Power Estimation, (04 2010) Malika Kharouf, Jamal Najim, Jack W. Silverstein, Walid Hachem. A CLT FOR INFORMATION- THEORETIC

Coupling biology and oceanography in models.

PubMed

Fennel, W; Neumann, T

2001-08-01

The dynamics of marine ecosystems, i.e. the changes of observable chemical-biological quantities in space and time, are driven by biological and physical processes. Predictions of future developments of marine systems need a theoretical framework, i.e. models, solidly based on research and understanding of the different processes involved. The natural way to describe marine systems theoretically seems to be the embedding of chemical-biological models into circulation models. However, while circulation models are relatively advanced the quantitative theoretical description of chemical-biological processes lags behind. This paper discusses some of the approaches and problems in the development of consistent theories and indicates the beneficial potential of the coupling of marine biology and oceanography in models.

Sensory evaluation based fuzzy AHP approach for material selection in customized garment design and development process

NASA Astrophysics Data System (ADS)

Hong, Y.; Curteza, A.; Zeng, X.; Bruniaux, P.; Chen, Y.

2016-06-01

Material selection is the most difficult section in the customized garment product design and development process. This study aims to create a hierarchical framework for material selection. The analytic hierarchy process and fuzzy sets theories have been applied to mindshare the diverse requirements from the customer and inherent interaction/interdependencies among these requirements. Sensory evaluation ensures a quick and effective selection without complex laboratory test such as KES and FAST, using the professional knowledge of the designers. A real empirical application for the physically disabled people is carried out to demonstrate the proposed method. Both the theoretical and practical background of this paper have indicated the fuzzy analytical network process can capture expert's knowledge existing in the form of incomplete, ambiguous and vague information for the mutual influence on attribute and criteria of the material selection.

Computational and Theoretical Study of the Physical Constraints on Chemotaxis

NASA Astrophysics Data System (ADS)

Varennes, Julien

Cell chemotaxis is crucial to many biological functions including development, wound healing, and cancer metastasis. Chemotaxis is the process in which cells migrate in response to chemical concentration gradients. Recent experiments show that cells are capable of detecting shallow gradients as small as a 1% concentration difference, and multicellular groups can improve on this by an additional order of magnitude. Examples from morphogenesis and metastasis demonstrate collective response to gradients equivalent to a 1 molecule difference in concentration across a cell body. While the physical constraints to cell gradient sensing are well understood, how the sensory information leads to cell migration, and coherent multicellular movement in the case of collectives, remains poorly understood. Here we examine how extrinsic sensory noise leads to error in chemotactic performance. First, we study single cell chemotaxis and use both simulations and analytical models to place physical constraints on chemotactic performance. Next we turn our attention to collective chemotaxis. We examine how collective cell interactions can improve chemotactic performance. We develop a novel model for quantifying the physical limit to chemotactic precision for two stereotypical modes of collective chemotaxis. Finally, we conclude by examining the effects of intercellular communication on collective chemotaxis. We use simulations to test how well collectives can chemotax through very shallow gradients with the help of communication. By studying these computational and theoretical models of individual and collective chemotaxis, we address the gap in knowledge between chemical sensing and directed migration.

Laser-Induced Translative Hydrodynamic Mass Snapshots: Noninvasive Characterization and Predictive Modeling via Mapping at Nanoscale

NASA Astrophysics Data System (ADS)

Wang, X. W.; Kuchmizhak, A. A.; Li, X.; Juodkazis, S.; Vitrik, O. B.; Kulchin, Yu. N.; Zhakhovsky, V. V.; Danilov, P. A.; Ionin, A. A.; Kudryashov, S. I.; Rudenko, A. A.; Inogamov, N. A.

2017-10-01

Subwavelength structures (meta-atoms) with artificially engineered permittivity and permeability have shown promising applications for guiding and controlling the flow of electromagnetic energy on the nanoscale. Ultrafast laser nanoprinting emerges as a promising single-step, green and flexible technology in fabricating large-area arrays of meta-atoms through the translative or ablative modification of noble-metal thin films. Ultrafast laser energy deposition in noble-metal films produces irreversible, intricate nanoscale translative mass redistributions after resolidification of the transient thermally assisted hydrodynamic melt perturbations. Such mass redistribution results in the formation of a radially symmetric frozen surface with modified hidden nanofeatures, which strongly affect the optical response harnessed in plasmonic sensing and nonlinear optical applications. Here, we demonstrate that side-view electron microscopy and ion-beam cross sections together with low-energy electron x-ray dispersion microscopy provide exact information about such three-dimensional patterns, enabling an accurate acquisition of their cross-sectional mass distributions. Such nanoscale solidified structures are theoretically modeled, considering the underlying physical processes associated with laser-induced energy absorption, electron-ion energy exchange, acoustic relaxation, and hydrodynamic flows. A theoretical approach, separating slow and fast physical processes and combining hybrid analytical two-temperature calculations, scalable molecular-dynamics simulations, and a semianalytical thin-shell model is synergistically applied. These advanced characterization approaches are required for a detailed modeling of near-field electromagnetic response and pave the way to a fully automated noninvasive in-line control of a high-throughput and large-scale laser fabrication. This theoretical modeling provides an accurate prediction of scales and topographies of the laser-fabricated meta-atoms and metasurfaces.

Top 10 Research Questions Related to Children Physical Activity Motivation

PubMed Central

Chen, Ang

2017-01-01

Physical activity is critical to healthy development of children. It is well documented that helping children develop and sustain a physically active lifestyle requires children to become motivated. Many studies have been conducted in the past 2.5 decades on determinants and correlates for children and adolescents’ physical activity motivation. The findings have informed researchers and practitioners about motivation sources for children and effective strategies to motivate children in given physical activity settings. Built on the extensive knowledge base and theoretical platforms formed by these research studies, the purpose of this article is to take a look at the current research landscape and provide subjective thoughts about what we still need to know about children’s physical activity motivation. The product of this subjective thinking process rendered 10 potential questions for future research on children’s physical activity motivation in both in-school and out-of-school settings. These topics encompass those focusing on children’s physical activity motivation as a mental dispositional process, those conceptualizing the motivation as an outcome of person–environment interactions, and those attempting to dissect the motivation as an outcome of social–cultural influences and educational policies. It is hoped that the topics can serve researchers interested in children’s physical activity motivation as starting blocks from which they can extend their conceptual thinking and identify research questions that are personally meaningful. It is also hoped that the list of potential questions can be helpful to researchers in accomplishing the imperative and significant mission to motivate children to be physically active in the 21st century and beyond. PMID:24592774

Top 10 research questions related to children physical activity motivation.

PubMed

Chen, Ang

2013-12-01

Physical activity is critical to healthy development of children. It is well documented that helping children develop and sustain a physically active lifestyle requires children to become motivated. Many studies have been conducted in the past 2.5 decades on determinants and correlates for children and adolescents' physical activity motivation. The findings have informed researchers and practitioners about motivation sources for children and effective strategies to motivate children in given physical activity settings. Built on the extensive knowledge base and theoretical platforms formed by these research studies, the purpose of this article is to take a look at the current research landscape and provide subjective thoughts about what we still need to know about children's physical activity motivation. The product of this subjective thinking process rendered 10 potential questions for future research on children's physical activity motivation in both in-school and out-of-school settings. These topics encompass those focusing on children's physical activity motivation as a mental dispositional process, those conceptualizing the motivation as an outcome of person-environment interactions, and those attempting to dissect the motivation as an outcome of social-cultural influences and educational policies. It is hoped that the topics can serve researchers interested in children's physical activity motivation as starting blocks from which they can extend their conceptual thinking and identify research questions that are personally meaningful. It is also hoped that the list of potential questions can be helpful to researchers in accomplishing the imperative and significant mission to motivate children to be physically active in the 21st century and beyond.

Calculation of the Intensity of Physical Time Fluctuations Using the Standard Solar Model and its Comparison with the Results of Experimental Measurements

NASA Astrophysics Data System (ADS)

Morozov, A. N.

2017-11-01

The article reviews the possibility of describing physical time as a random Poisson process. An equation allowing the intensity of physical time fluctuations to be calculated depending on the entropy production density within irreversible natural processes has been proposed. Based on the standard solar model the work calculates the entropy production density inside the Sun and the dependence of the intensity of physical time fluctuations on the distance to the centre of the Sun. A free model parameter has been established, and the method of its evaluation has been suggested. The calculations of the entropy production density inside the Sun showed that it differs by 2-3 orders of magnitude in different parts of the Sun. The intensity of physical time fluctuations on the Earth's surface depending on the entropy production density during the sunlight-to-Earth's thermal radiation conversion has been theoretically predicted. A method of evaluation of the Kullback's measure of voltage fluctuations in small amounts of electrolyte has been proposed. Using a simple model of the Earth's surface heat transfer to the upper atmosphere, the effective Earth's thermal radiation temperature has been determined. A comparison between the theoretical values of the Kullback's measure derived from the fluctuating physical time model and the experimentally measured values of this measure for two independent electrolytic cells showed a good qualitative and quantitative concurrence of predictions of both theoretical model and experimental data.

Physics of metabolic organization

NASA Astrophysics Data System (ADS)

Jusup, Marko; Sousa, Tânia; Domingos, Tiago; Labinac, Velimir; Marn, Nina; Wang, Zhen; Klanjšček, Tin

2017-03-01

We review the most comprehensive metabolic theory of life existing to date. A special focus is given to the thermodynamic roots of this theory and to implications that the laws of physics-such as the conservation of mass and energy-have on all life. Both the theoretical foundations and biological applications are covered. Hitherto, the foundations were more accessible to physicists or mathematicians, and the applications to biologists, causing a dichotomy in what always should have been a single body of work. To bridge the gap between the two aspects of the same theory, we (i) adhere to the theoretical formalism, (ii) try to minimize the amount of information that a reader needs to process, but also (iii) invoke examples from biology to motivate the introduction of new concepts and to justify the assumptions made, and (iv) show how the careful formalism of the general theory enables modular, self-consistent extensions that capture important features of the species and the problem in question. Perhaps the most difficult among the introduced concepts, the utilization (or mobilization) energy flow, is given particular attention in the form of an original and considerably simplified derivation. Specific examples illustrate a range of possible applications-from energy budgets of individual organisms, to population dynamics, to ecotoxicology.

Concrete Geometry: Playing with Blocks

ERIC Educational Resources Information Center

Luescher, Andreas

2010-01-01

This article describes a design/build exercise conducted in an Architectural Materials and Methods class to achieve three interrelated objectives: (1) to apply physically the semester's theoretical focus on the constituent process and languages of architecture investigations, (2) to capitalise on the physical and aesthetic properties of concrete…

Solar Physics

NASA Technical Reports Server (NTRS)

Wu, S. T.

2000-01-01

The areas of emphasis are: (1) develop theoretical models of the transient release of magnetic energy in the solar atmosphere, e.g., in solar flares, eruptive prominences, coronal mass ejections, etc.; (2) investigate the role of the Sun's magnetic field in the structuring of solar corona by the development of three-dimensional numerical models that describe the field configuration at various heights in the solar atmosphere by extrapolating the field at the photospheric level; (3) develop numerical models to investigate the physical parameters obtained by the ULYSSES mission; (4) develop numerical and theoretical models to investigate solar activity effects on the solar wind characteristics for the establishment of the solar-interplanetary transmission line; and (5) develop new instruments to measure solar magnetic fields and other features in the photosphere, chromosphere transition region and corona. We focused our investigation on the fundamental physical processes in solar atmosphere which directly effect our Planet Earth. The overall goal is to establish the physical process for the Sun-Earth connections.

What is This Thing Called Sensemaking?: A Theoretical Framework for How Physics Students Resolve Inconsistencies in Understanding

NASA Astrophysics Data System (ADS)

Odden, Tor Ole B.

Students often emerge from introductory physics courses with a feeling that the concepts they have learned do not make sense. In recent years, science education researchers have begun to attend to this type of problem by studying the ways in which students make sense of science concepts. However, although many researchers agree intuitively on what sensemaking looks like, the literature on sensemaking is both theoretically fragmented and provides few guidelines for how to encourage and support the process. In this dissertation, I address this challenge by proposing a theoretical framework to describe students' sensemaking processes. I base this framework both on the science education research literature on sensemaking and on a series of video-recorded cognitive, clinical interviews conducted with introductory physics students enrolled in a course on electricity and magnetism. Using the science education research literature on sensemaking as well as a cognitivist, dynamic network model of mind as a theoretical lens, I first propose a coherent definition of sensemaking. Then, using this definition I analyze the sensemaking processes of these introductory physics students during episodes when they work to articulate and resolve gaps or inconsistencies in their understanding. Based on the students' framing, gestures, and dialogue I argue that the process of sensemaking unfolds in a distinct way, which we can describe as an epistemic game in which students first build a framework of knowledge, then identify a gap or inconsistency in that framework, iteratively build an explanation to resolve the gap or inconsistency, and (sometimes) successfully resolve it. I further argue that their entry into the sensemaking frame is facilitated by a specific question, which is in turn motivated by a gap or inconsistency in knowledge that I call the vexation point. I also investigate the results of sensemaking, arguing that students may use the technique of conceptual blending to both "defragment" their knowledge and resolve their vexation points.

The physics of the earth's core: An introduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melchior, P.

1986-01-01

This book is a reference text providing information on physical topics of recent developments in internal geophysics. The text summarizes papers covering theoretical geophysics. Basic formulae, definitions and theorems are not explained in detail due to the limited space. The contents include applications to geodesy, geophysics, astronomy, astrophysics, geophysics and planetary physics. The formal contents include: The Earth's model; Thermodynamics; Hydrodynamics; Geomagnetism; Geophysical implications in the Earth's core.

Statistical analysis and modeling of intermittent transport events in the tokamak scrape-off layer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, Johan, E-mail: anderson.johan@gmail.com; Halpern, Federico D.; Ricci, Paolo

The turbulence observed in the scrape-off-layer of a tokamak is often characterized by intermittent events of bursty nature, a feature which raises concerns about the prediction of heat loads on the physical boundaries of the device. It appears thus necessary to delve into the statistical properties of turbulent physical fields such as density, electrostatic potential, and temperature, focusing on the mathematical expression of tails of the probability distribution functions. The method followed here is to generate statistical information from time-traces of the plasma density stemming from Braginskii-type fluid simulations and check this against a first-principles theoretical model. The analysis ofmore » the numerical simulations indicates that the probability distribution function of the intermittent process contains strong exponential tails, as predicted by the analytical theory.« less

Biofield Science: Current Physics Perspectives.

PubMed

Kafatos, Menas C; Chevalier, Gaétan; Chopra, Deepak; Hubacher, John; Kak, Subhash; Theise, Neil D

2015-11-01

This article briefly reviews the biofield hypothesis and its scientific literature. Evidence for the existence of the biofield now exists, and current theoretical foundations are now being developed. A review of the biofield and related topics from the perspective of physical science is needed to identify a common body of knowledge and evaluate possible underlying principles of origin of the biofield. The properties of such a field could be based on electromagnetic fields, coherent states, biophotons, quantum and quantum-like processes, and ultimately the quantum vacuum. Given this evidence, we intend to inquire and discuss how the existence of the biofield challenges reductionist approaches and presents its own challenges regarding the origin and source of the biofield, the specific evidence for its existence, its relation to biology, and last but not least, how it may inform an integrated understanding of consciousness and the living universe.

Quantum dynamics of a two-atom-qubit system

NASA Astrophysics Data System (ADS)

Van Hieu, Nguyen; Bich Ha, Nguyen; Linh, Le Thi Ha

2009-09-01

A physical model of the quantum information exchange between two qubits is studied theoretically. The qubits are two identical two-level atoms, the physical mechanism of the quantum information exchange is the mutual dependence of the reduced density matrices of two qubits generated by their couplings with a multimode radiation field. The Lehmberg-Agarwal master equation is exactly solved. The explicit form of the mutual dependence of two reduced density matrices is established. The application to study the entanglement of two qubits is discussed.

Circumstellar radio molecular lines

NASA Technical Reports Server (NTRS)

NGUYEN-QUANG-RIEU

1987-01-01

Radio molecular lines appear to be useful probes into the stellar environment. Silicon oxide masers provide information on the physical conditions in the immediate vicinity of the stellar photosphere. Valuable information on the physics operating in the envelope of IRC + 10216 was recently obtained by high sensitivity observations and detailed theoretical analyses. Infrared speckle interferometry in the molecular lines and in the continuum is helpful in the investigation of the inner region of the envelope. These techniques are discussed in terms of late-type star mass loss.

Special issue on quantum physics with non-Hermitian operators Special issue on quantum physics with non-Hermitian operators

NASA Astrophysics Data System (ADS)

Bender, Carl M.; Fring, Andreas; Guenther, Uwe; Jones, Hugh F.

2012-01-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to quantum physics with non-Hermitian operators. The main motivation behind this special issue is to gather together recent results, developments and open problems in this rapidly evolving field of research in a single comprehensive volume. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will be open to all contributions containing new results on non-Hermitian theories which are explicitly PT-symmetric and/or pseudo-Hermitian or quasi-Hermitian. The main novelties in the past years in this area have been many experimental observations, realizations, and applications of PT symmetric Hamiltonians in optics and microwave cavities. We especially invite contributions on the theoretical interpretations of these recent PT-symmetric experiments and on theoretical proposals for new experiments. Editorial policy The Guest Editors for this issue are Carl Bender, Andreas Fring, Uwe Guenther and Hugh Jones. The areas and topics for this issue include, but are not limited to: spectral problems novel properties of complex optical potentials PT-symmetry related threshold lasers and spectral singularities construction of metric operators scattering theory supersymmetric theories Lie algebraic and Krein-space methods random matrix models classical and semi-classical models exceptional points in model systems operator theoretic approaches microwave cavities aspects of integrability and exact solvability field theories with indefinite metric All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The deadline for contributed papers will be 31 March 2012. This deadline will allow the special issue to appear before the end of November 2012. There is a nominal page limit of 15 printed pages per contribution (invited review papers can be longer). For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on publishing your work in Journal of Physics A: Mathematical and Theoretical may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via authors.iop.org/, or by email to jphysa@iop.org, quoting 'JPhysA Special issue on quantum physics with non-Hermitian operators'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Special issue on quantum physics with non-Hermitian operators Special issue on quantum physics with non-Hermitian operators

NASA Astrophysics Data System (ADS)

Bender, Carl M.; Fring, Andreas; Guenther, Uwe; Jones, Hugh F.

2012-01-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to quantum physics with non-Hermitian operators. The main motivation behind this special issue is to gather together recent results, developments and open problems in this rapidly evolving field of research in a single comprehensive volume. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will be open to all contributions containing new results on non-Hermitian theories which are explicitly PT-symmetric and/or pseudo-Hermitian or quasi-Hermitian. The main novelties in the past years in this area have been many experimental observations, realizations, and applications of PT symmetric Hamiltonians in optics and microwave cavities. We especially invite contributions on the theoretical interpretations of these recent PT-symmetric experiments and on theoretical proposals for new experiments. Editorial policy The Guest Editors for this issue are Carl Bender, Andreas Fring, Uwe Guenther and Hugh Jones. The areas and topics for this issue include, but are not limited to: spectral problems novel properties of complex optical potentials PT-symmetry related threshold lasers and spectral singularities construction of metric operators scattering theory supersymmetric theories Lie algebraic and Krein-space methods random matrix models classical and semi-classical models exceptional points in model systems operator theoretic approaches microwave cavities aspects of integrability and exact solvability field theories with indefinite metric All contributions will be refereed and processed according to the usual procedure of the journal. Papers should report original and significant research that has not already been published. Guidelines for preparation of contributions The deadline for contributed papers will be 31 March 2012. This deadline will allow the special issue to appear before the end of November 2012. There is a nominal page limit of 15 printed pages per contribution (invited review papers can be longer). For papers exceeding this limit, the Guest Editors reserve the right to request a reduction in length. Further advice on publishing your work in Journal of Physics A: Mathematical and Theoretical may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via authors.iop.org, or by email to jphysa@iop.org, quoting 'JPhysA Special issue on quantum physics with non-Hermitian operators'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Human Factors of CC-130 Operations. Volume 5: Human Factors in Decision Making

DTIC Science & Technology

1998-02-01

known about human information processing and decision making. Topics for HFDM training come directly from this theoretical framework . The proposed...The proposed training can be distinguished from other approaches with similar goals (either explicit or implicit) by its base within a theoretical ... framework of human information processing. The differences lie less in the content than in the way the material is organized and shaped by theory. The

Magnetohydrodynamic Particle Acceleration Processes: SSX Experiments, Theory, and Astrophysical Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Michael R.

2006-11-16

Project Title: Magnetohydrodynamic Particle Acceleration Processes: SSX Experiments, Theory, and Astrophysical Applications PI: Michael R. Brown, Swarthmore College The purpose of the project was to provide theoretical and modeling support to the Swarthmore Spheromak Experiment (SSX). Accordingly, the theoretical effort was tightly integrated into the SSX experimental effort. During the grant period, Michael Brown and his experimental collaborators at Swarthmore, with assistance from W. Matthaeus as appropriate, made substantial progress in understanding the physics SSX plasmas.

THE ROLE AND DISTRIBUTION OF WRITTEN INFORMAL COMMUNICATION IN THEORETICAL HIGH ENERGY PHYSICS.

ERIC Educational Resources Information Center

LIBBEY, MILES A.; ZALTMAN, GERALD

THIS STUDY OF "PREPRINT" DISTRIBUTION IN THEORECTICAL HIGH ENERGY PHYSICS USED A QUESTIONNAIRE CIRCULATED TO ALL KNOWN HIGH ENERGY THEORISTS. A SECOND QUESTIONNAIRE WAS SENT TO A REPRESENTATIVE SAMPLE OF "PREPRINT LIBRARIANS" AT VARIOUS INSTITUTIONS IN THE U.S. AND ABROAD. BASED ON THIS DATA, THE STUDY CONCLUDED THAT AN EXPERIMENT WITH CENTRALIZED…

An Information Processing Perspective on Divergence and Convergence in Collaborative Learning

ERIC Educational Resources Information Center

Jorczak, Robert L.

2011-01-01

This paper presents a model of collaborative learning that takes an information processing perspective of learning by social interaction. The collaborative information processing model provides a theoretical basis for understanding learning principles associated with social interaction and explains why peer-to-peer discussion is potentially more…

Computational manufacturing as a bridge between design and production.

PubMed

Tikhonravov, Alexander V; Trubetskov, Michael K

2005-11-10

Computational manufacturing of optical coatings is a research area that can be placed between theoretical designing and practical manufacturing in the same way that computational physics can be placed between theoretical and experimental physics. Investigations in this area have been performed for more than 30 years under the name of computer simulation of manufacturing and monitoring processes. Our goal is to attract attention to the increasing importance of computational manufacturing at the current state of the art in the design and manufacture of optical coatings and to demonstrate possible applications of this research tool.

Computational manufacturing as a bridge between design and production

NASA Astrophysics Data System (ADS)

Tikhonravov, Alexander V.; Trubetskov, Michael K.

2005-11-01

Computational manufacturing of optical coatings is a research area that can be placed between theoretical designing and practical manufacturing in the same way that computational physics can be placed between theoretical and experimental physics. Investigations in this area have been performed for more than 30 years under the name of computer simulation of manufacturing and monitoring processes. Our goal is to attract attention to the increasing importance of computational manufacturing at the current state of the art in the design and manufacture of optical coatings and to demonstrate possible applications of this research tool.

Random numbers certified by Bell's theorem.

PubMed

Pironio, S; Acín, A; Massar, S; de la Giroday, A Boyer; Matsukevich, D N; Maunz, P; Olmschenk, S; Hayes, D; Luo, L; Manning, T A; Monroe, C

2010-04-15

Randomness is a fundamental feature of nature and a valuable resource for applications ranging from cryptography and gambling to numerical simulation of physical and biological systems. Random numbers, however, are difficult to characterize mathematically, and their generation must rely on an unpredictable physical process. Inaccuracies in the theoretical modelling of such processes or failures of the devices, possibly due to adversarial attacks, limit the reliability of random number generators in ways that are difficult to control and detect. Here, inspired by earlier work on non-locality-based and device-independent quantum information processing, we show that the non-local correlations of entangled quantum particles can be used to certify the presence of genuine randomness. It is thereby possible to design a cryptographically secure random number generator that does not require any assumption about the internal working of the device. Such a strong form of randomness generation is impossible classically and possible in quantum systems only if certified by a Bell inequality violation. We carry out a proof-of-concept demonstration of this proposal in a system of two entangled atoms separated by approximately one metre. The observed Bell inequality violation, featuring near perfect detection efficiency, guarantees that 42 new random numbers are generated with 99 per cent confidence. Our results lay the groundwork for future device-independent quantum information experiments and for addressing fundamental issues raised by the intrinsic randomness of quantum theory.

DEB modeling for nanotoxicology, microbial ecology, and environmental engineering. Comment on: ;Physics of metabolic organization; by Marko Jusup et al.

NASA Astrophysics Data System (ADS)

Holden, Patricia A.

2017-03-01

Jusup et al. [1] appeal to mathematical physicists, and to biologists, by providing the theoretical basis for dynamic energy budget (DEB) modeling of individual organisms and populations, while emphasizing model simplicity, universality, and applicability to real world problems. Comments herein regard the disciplinary tensions proposed by the authors and suggest that-in addition to important applications in eco- and specifically nano-toxicology-there are opportunities for DEB frameworks to inform relative complexity in microbial ecological process modeling. This commentary also suggests another audience for bridging DEB theory and application-engineers solving environmental problems.

Lieb-Robinson bound and locality for general markovian quantum dynamics.

PubMed

Poulin, David

2010-05-14

The Lieb-Robinson bound shows the existence of a maximum speed of signal propagation in discrete quantum mechanical systems with local interactions. This generalizes the concept of relativistic causality beyond field theory, and provides a powerful tool in theoretical condensed matter physics and quantum information science. Here, we extend the scope of this seminal result by considering general markovian quantum evolution, where we prove that an equivalent bound holds. In addition, we use the generalized bound to demonstrate that correlations in the stationary state of a Markov process decay on a length scale set by the Lieb-Robinson velocity and the system's relaxation time.

Decision theory and information propagation in quantum physics

NASA Astrophysics Data System (ADS)

Forrester, Alan

In recent papers, Zurek [(2005). Probabilities from entanglement, Born's rule p k =| ψ k | 2 from entanglement. Physical Review A, 71, 052105] has objected to the decision-theoretic approach of Deutsch [(1999) Quantum theory of probability and decisions. Proceedings of the Royal Society of London A, 455, 3129-3137] and Wallace [(2003). Everettian rationality: defending Deutsch's approach to probability in the Everett interpretation. Studies in History and Philosophy of Modern Physics, 34, 415-438] to deriving the Born rule for quantum probabilities on the grounds that it courts circularity. Deutsch and Wallace assume that the many worlds theory is true and that decoherence gives rise to a preferred basis. However, decoherence arguments use the reduced density matrix, which relies upon the partial trace and hence upon the Born rule for its validity. Using the Heisenberg picture and quantum Darwinism-the notion that classical information is quantum information that can proliferate in the environment pioneered in Ollivier et al. [(2004). Objective properties from subjective quantum states: Environment as a witness. Physical Review Letters, 93, 220401 and (2005). Environment as a witness: Selective proliferation of information and emergence of objectivity in a quantum universe. Physical Review A, 72, 042113]-I show that measurement interactions between two systems only create correlations between a specific set of commuting observables of system 1 and a specific set of commuting observables of system 2. This argument picks out a unique basis in which information flows in the correlations between those sets of commuting observables. I then derive the Born rule for both pure and mixed states and answer some other criticisms of the decision theoretic approach to quantum probability.

A Comparison of Subjective and Objective Job Demands and Fit with Personal Resources as Predictors of Retirement Timing in a National U.S. Sample

PubMed Central

Sonnega, Amanda; Helppie-McFall, Brooke; Hudomiet, Peter; Willis, Robert J.; Fisher, Gwenith G.

2017-01-01

Population aging and attendant pressures on public budgets have spurred considerable interest in understanding factors that influence retirement timing. A range of sociodemographic and economic characteristics predict both earlier and later retirement. Less is known about the role of job characteristics on the work choices of older workers. Researchers are increasingly using the subjective ratings of job characteristics available in the Health and Retirement Study in conjunction with more objective measures of job characteristics from the Occupational Information Network (O*NET) database. Employing a theoretically-informed model of job demands-personal resources fit, we constructed mismatch measures between resources and job demands (both subjectively and objectively assessed) in physical, emotional, and cognitive domains. When we matched comparable measures across the two data sources in the domains of physical, emotional, and cognitive job demands, we found that both sources of information held predictive power in relation to retirement timing. Physical and emotional but not cognitive mismatch were associated with earlier retirement. We discuss theoretical and practical implications of these findings and directions for future research. PMID:29270302

Strategic and Nonstrategic Information Acquisition.

ERIC Educational Resources Information Center

Berger, Charles R.

2002-01-01

Uses dual-process theories and research concerned with automaticity and the role conceptual short-term memory plays in visual information processing to illustrate both the ubiquity of nonstrategic information acquisition during interpersonal communication and its potential consequences on judgments and behavior. Discusses theoretical and…

All Ionospheres are not Alike: Reports from other Planets

NASA Technical Reports Server (NTRS)

Nagy, Andrew F.; Cravens, Thomas E.; Waite, H. J., Jr.

1995-01-01

Our understanding of planetary ionospheres made some progress during the last four years. Most of this progress was due to new and/or improved theoretical models, although some new data were also obtained by direct and remote sensing observations. The very basic processes such as ionization, chemical transformations and diffusive as well as convective transports are analogous in all ionospheres; the major differences are the result of factors such as different neutral atmospheres, intrinsic magnetic field strength, distance from the Sun, etc. Improving our understanding of any of the ionospheres in our solar system helps in elucidating the controlling physical and chemical processes in all of them. New measurements are needed to provide new impetus, as well as guidance, in advancing our understanding and we look forward to such information in the years ahead.

Community resiliency as a measure of collective health status: perspectives from rural communities.

PubMed

Kulig, Judith C; Edge, Dana; Joyce, Brenda

2008-12-01

Community resiliency is a theoretical framework useful for describing the process used by communities to address adversity. A mixed-method 2-year case study was conducted to gather information about community resiliency in 2 rural communities. This article focuses on the themes generated from qualitative interviews with 55 members of these communities. The participants viewed community as a place of interdependence and interaction. The majority saw community resiliency as the ability to address challenges. Characteristics included physical and social infrastructure, population characteristics, conceptual characteristics, and problem-solving processes. Barriers included negative individual attitudes and lack of infrastructure in rural communities. Nurses could play a key role in enhancing the resiliency of rural communities by developing and implementing programs based on the Community Resiliency Model, which was supported in this study.

Information theoretic analysis of edge detection in visual communication

NASA Astrophysics Data System (ADS)

Jiang, Bo; Rahman, Zia-ur

2010-08-01

Generally, the designs of digital image processing algorithms and image gathering devices remain separate. Consequently, the performance of digital image processing algorithms is evaluated without taking into account the artifacts introduced into the process by the image gathering process. However, experiments show that the image gathering process profoundly impacts the performance of digital image processing and the quality of the resulting images. Huck et al. proposed one definitive theoretic analysis of visual communication channels, where the different parts, such as image gathering, processing, and display, are assessed in an integrated manner using Shannon's information theory. In this paper, we perform an end-to-end information theory based system analysis to assess edge detection methods. We evaluate the performance of the different algorithms as a function of the characteristics of the scene, and the parameters, such as sampling, additive noise etc., that define the image gathering system. The edge detection algorithm is regarded to have high performance only if the information rate from the scene to the edge approaches the maximum possible. This goal can be achieved only by jointly optimizing all processes. People generally use subjective judgment to compare different edge detection methods. There is not a common tool that can be used to evaluate the performance of the different algorithms, and to give people a guide for selecting the best algorithm for a given system or scene. Our information-theoretic assessment becomes this new tool to which allows us to compare the different edge detection operators in a common environment.

Achievement Evaluation within a Non-Conventional Framework: Some Experiences in Physics and Humour

ERIC Educational Resources Information Center

Worner, C. H.; Romero, A.; Bustamante, G.

2010-01-01

An achievement evaluation of a non-conventional physics course for liberal arts students is presented. The theoretical ground for this course focuses on the use of humour as a teaching tool. Preliminary evidence shows that a learning process is accomplished. (Contains 1 table and 3 figures.)

Advanced Quantitative Measurement Methodology in Physics Education Research

ERIC Educational Resources Information Center

Wang, Jing

2009-01-01

The ultimate goal of physics education research (PER) is to develop a theoretical framework to understand and improve the learning process. In this journey of discovery, assessment serves as our headlamp and alpenstock. It sometimes detects signals in student mental structures, and sometimes presents the difference between expert understanding and…

Native and Nonnative Processing of Japanese Pitch Accent

ERIC Educational Resources Information Center

Wu, Xianghua; Tu, Jung-Yueh; Wang, Yue

2012-01-01

The theoretical framework of this study is based on the prevalent debate of whether prosodic processing is influenced by higher level linguistic-specific circuits or reflects lower level encoding of physical properties. Using the dichotic listening technique, the study investigates the hemispheric processing of Japanese pitch accent by native…

Report of the theory panel. [space physics

NASA Technical Reports Server (NTRS)

Ashourabdalla, Maha; Rosner, Robert; Antiochos, Spiro; Curtis, Steven; Fejer, B.; Goertz, Christoph K.; Goldstein, Melvyn L.; Holzer, Thomas E.; Jokipii, J. R.; Lee, Lou-Chuang

1991-01-01

The ultimate goal of this research is to develop an understanding which is sufficiently comprehensive to allow realistic predictions of the behavior of the physical systems. Theory has a central role to play in the quest for this understanding. The level of theoretical description is dependent on three constraints: (1) the available computer hardware may limit both the number and the size of physical processes the model system can describe; (2) the fact that some natural systems may only be described in a statistical manner; and (3) the fact that some natural systems may be observable only through remote sensing which is intrinsically limited by spatial resolution and line of sight integration. From this the report discusses present accomplishments and future goals of theoretical space physics. Finally, the development and use of new supercomputer is examined.

PREFACE: Quantum Information, Communication, Computation and Cryptography

NASA Astrophysics Data System (ADS)

Benatti, F.; Fannes, M.; Floreanini, R.; Petritis, D.

2007-07-01

The application of quantum mechanics to information related fields such as communication, computation and cryptography is a fast growing line of research that has been witnessing an outburst of theoretical and experimental results, with possible practical applications. On the one hand, quantum cryptography with its impact on secrecy of transmission is having its first important actual implementations; on the other hand, the recent advances in quantum optics, ion trapping, BEC manipulation, spin and quantum dot technologies allow us to put to direct test a great deal of theoretical ideas and results. These achievements have stimulated a reborn interest in various aspects of quantum mechanics, creating a unique interplay between physics, both theoretical and experimental, mathematics, information theory and computer science. In view of all these developments, it appeared timely to organize a meeting where graduate students and young researchers could be exposed to the fundamentals of the theory, while senior experts could exchange their latest results. The activity was structured as a school followed by a workshop, and took place at The Abdus Salam International Center for Theoretical Physics (ICTP) and The International School for Advanced Studies (SISSA) in Trieste, Italy, from 12-23 June 2006. The meeting was part of the activity of the Joint European Master Curriculum Development Programme in Quantum Information, Communication, Cryptography and Computation, involving the Universities of Cergy-Pontoise (France), Chania (Greece), Leuven (Belgium), Rennes1 (France) and Trieste (Italy). This special issue of Journal of Physics A: Mathematical and Theoretical collects 22 contributions from well known experts who took part in the workshop. They summarize the present day status of the research in the manifold aspects of quantum information. The issue is opened by two review articles, the first by G Adesso and F Illuminati discussing entanglement in continuous variable systems, the second by T Prosen, discussing chaos and complexity in quantum systems. Both topics have theoretical as well as experimental relevance and are likely to witness a fast growing development in the near future. The remaining contributions present more specific and very recent results. They involve the study of the structure of quantum states and their estimation (B Baumgartner et al, C King et al, S Olivares et al, D Petz et al and W van Dam et al), of entanglement generation and its quantification (G Brida et al, F Ciccarello et al, G Costantini et al, O Romero-Isart et al, D Rossini et al, A Serafini et al and D Vitali et al), of randomness related effects on entanglement behaviour (I Akhalwaya et al, O Dahlsten et al and L Viola et al), and of abstract and applied aspects of quantum computation and communication (K Audenart, G M D'Ariano et al, N Datta et al, L C Kwek et al and M Nathanson et al). We would like to express our gratitude to the European Commission, the Abdus Salam ICTP, SISSA and Eurotech SpA (Amaro, Udine, Italy) for financial and/or logistic support. Special thanks also go to the workshop secretary Marina De Comelli, and the secretaries of the Department of Theoretical Physics, University of Trieste, Sabrina Gaspardis and Rosita Glavina for their precious help and assistance.

A neuromathematical model of human information processing and its application to science content acquisition

NASA Astrophysics Data System (ADS)

Anderson, O. Roger

The rate of information processing during science learning and the efficiency of the learner in mobilizing relevant information in long-term memory as an aid in transmitting newly acquired information to stable storage in long-term memory are fundamental aspects of science content acquisition. These cognitive processes, moreover, may be substantially related in tempo and quality of organization to the efficiency of higher thought processes such as divergent thinking and problem-solving ability that characterize scientific thought. As a contribution to our quantitative understanding of these fundamental information processes, a mathematical model of information acquisition is presented and empirically evaluated in comparison to evidence obtained from experimental studies of science content acquisition. Computer-based models are used to simulate variations in learning parameters and to generate the theoretical predictions to be empirically tested. The initial tests of the predictive accuracy of the model show close agreement between predicted and actual mean recall scores in short-term learning tasks. Implications of the model for human information acquisition and possible future research are discussed in the context of the unique theoretical framework of the model.

PREFACE Turbulent Mixing and Beyond

NASA Astrophysics Data System (ADS)

Abarzhi, Snezhana I.; Gauthier, Serge; Niemela, Joseph J.

2010-12-01

The goals of the International Conference 'Turbulent Mixing and Beyond', TMB-2009, are to expose the generic problem of non-equilibrium turbulent processes to a broad scientific community, to promote the development of new ideas in tackling the fundamental aspects of the problem, to assist in the application of novel approaches in a broad range of phenomena, where the turbulent processes occur, and to have a potential impact on technology. The Conference provides the opportunity to bring together researchers from different areas, which include but are not limited to fluid dynamics, plasmas, high energy density physics, astrophysics, material science, combustion, atmospheric and Earth sciences, nonlinear and statistical physics, applied mathematics, probability and statistics, data processing and computations, optics and telecommunications, and to have their attention focused on the long-standing formidable task of non-equilibrium processes. Non-equilibrium turbulent processes play a key role in a broad variety of phenomena spanning astrophysical to atomistic scales and high or low energy density regimes. Inertial confinement and magnetic fusion, light-matter interaction and non-equilibrium heat transfer, strong shocks and explosions, material transformation under high strain rate, supernovae and accretion disks, stellar non-Boussinesq and magneto-convection, planetary interiors and mantle-lithosphere tectonics, premixed and non-premixed combustion, non-canonical wall-bounded flows, hypersonic and supersonic boundary layers, dynamics of atmosphere and oceanography, are just a few examples. A grip on non-equilibrium turbulent processes is crucial for cutting-edge technology such as laser micro-machining, nano-electronics, free-space optical telecommunications, and for industrial applications in the areas of aeronautics and aerodynamics. Non-equilibrium turbulent processes are anisotropic, non-local, multi-scale and multi-phase, and often are driven by shocks or acceleration. Their scaling, spectral and invariant properties differ substantially from those of classical Kolmogorov turbulence. At atomistic and meso-scales, the non-equilibrium dynamics depart dramatically from a standard scenario given by the Gibbs statistic ensemble average and quasi-static Boltzmann equation. The singular aspect and the similarity of the non-equilibrium dynamics at macroscopic scales are interplayed with the fundamental properties of the Euler and compressible Navier-Stokes equations and with the problem sensitivity to the boundary conditions at discontinuities. The state-of-the-art numerical simulations of multi-phase flows suggest new methods for predictive modeling of the multi-scale non-equilibrium dynamics in fluids and plasmas, up to peta-scale level, for error estimate and uncertainty quantification, as well as for novel data assimilation techniques. The Second International Conference and Advanced School 'Turbulent Mixing and Beyond', TMB-2009, was held on 27 July-7 August 2009 at the Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy. This was a highly informative and exciting meeting, and it strengthened and reaffirmed the success of TMB-2007. TMB-2009 brought together over 180 participants from five continents, ranging from students to members of National Academies of Sciences and Engineering and including researchers at experienced and early stages of their carriers from leading scientific institutions in academia, national laboratories, corporations and industry, from developed and developing countries. The success of TMB-2009 came from the successful work of all the participants, who were responsible professionals caring for the quality of their research and sharing their scientific vision. The level of presentations was high; about 170 presentations included over 60 invited lectures and 15 tutorials (4500 minutes of talks in total), about 40 posters and two Round Tables. TMB-2009 covered 17 different topics, maintaining the scope and the interdisciplinary character of the meeting while keeping the focus on a fundamental scientific problem of non-equilibrium processes and on the Conference objectives. The abstracts of the 194 accepted presentations of more than 400 authors were published in the Book of Abstracts of the Second International Conference and Advanced School 'Turbulent Mixing and Beyond', 27 July-7 August 2009 , Copyright © 2009, the Abdus Salam International Centre for Theoretical Physics, Trieste, Italy (ISBN 92095003-41-1). This Topical Issue consists of 70 articles accepted for publication in the Conference Proceedings and represents a substantial part of the Conference contributions. The articles are in a broad variety of TMB-2009 themes and are sorted alphabetically by the last name of the first author within each of the following topics: Canonical turbulence and turbulent mixing: invariant, scaling, spectral properties, scalar transports, convection; Wall-bounded flows: structure and fundamentals, non-canonical turbulent boundary layers, including unsteady and transitional flows, supersonic and hypersonic flows, shock-boundary layer interactions; Non-equilibrium processes: unsteady, multiphase and shock-driven turbulent flows, anisotropic non-local dynamics, connection of continuous description at macro-scales to kinetic processes at atomistic scales; Interfacial dynamics: instabilities of Rayleigh-Taylor, Kelvin-Helmholtz, Richtmyer-Meshkov, Landau-Darrieus, Saffman-Taylor High energy density physics: inertial confinement and heavy-ion fusion, Z-pinches, light-matter and laser-plasma interactions, non-equilibrium heat transfer; Material science: material transformation under high strain rates, equation of state, impact dynamics, mixing at nano- and micro-scales; Astrophysics: supernovae, interstellar medium, star formation, stellar interiors, early Universe, cosmic-microwave background, accretion disks; Magneto-hydrodynamics: magnetic fusion and magnetically confined plasmas, magneto-convection, magneto-rotational instability, dynamo; Canonical plasmas: coupled plasmas, anomalous resistance, ionosphere; Physics of atmosphere: environmental fluid dynamics, weather forecasting, turbulent flows in stratified media and atmosphere, non-Boussinesq convection; Geophysics and Earth science: mantle-lithosphere tectonics, oceanography, turbulent convection under rotation, planetary interiors; Combustion: dynamics of flames and fires, deflagration-to-detonation transition, blast waves and explosions, flows with chemical reactions, flows in jet engines; Mathematical aspects of non-equilibrium dynamics: vortex dynamics, singularities, discontinuities, asymptotic dynamics, weak solutions, well- and ill-posedness, continuous transports out of thermodynamic equilibrium; Stochastic processes and probabilistic description: long-tail distributions and anomalous diffusion, data assimilation and processing methodologies, error estimate and uncertainty quantification, statistically unsteady processes; Advanced numerical simulations: continuous DNS/LES/RANS, molecular dynamics, Monte-Carlo, predictive modeling, validation and verification of numerical models; Experimental diagnostics: model experiments in high energy density and low energy density regimes, plasma diagnostics, fluid flow visualizations and control, opto-fluidics, novel optical methods, holography, advanced technologies. TMB-2009 was organized by the following members of the Organizing Committee: Snezhana I Abarzhi (chairperson, Chicago, USA) Malcolm J Andrews (Los Alamos National Laboratory, USA) Sergei I Anisimov (Landau Institute for Theoretical Physics, Russia) Hiroshi Azechi (Institute of Laser Engineering, Osaka, Japan) Serge Gauthier (Commissariat à l'Energie Atomique, France) Christopher J Keane (Lawrence Livermore National Laboratory, USA) Robert Rosner (Argonne National Laboratory, USA) Katepalli R Sreenivasan (International Centre for Theoretical Physics, Italy) Alexander L Velikovich (Naval Research Laboratory, USA) and the Local Organizing Committee at the International Centre for Theoretical Physics, Italy Joseph J Niemela Katepalli R Sreenivasan with the assistance of Suzie Radosic (administrator and assistant, ICTP) Daniil Ilyin (web-master, University of Chicago Laboratory Schools, Chicago, USA) The Conference and the School were sponsored by several Agencies and Institutions in the USA, Europe and Japan. The Organizing Committee of TMB-2009 gratefully acknowledges the support of International Centre for Theoretical Physics (ICTP), Italy National Science Foundation (NSF), USA Programs: Plasma Physics; Astronomy and Astrophysics; Computational Mathematics; Applied Mathematics; Fluid Dynamics; Combustion, Fire and Plasma Systems; Cyber-Physical Systems; Computer and Network Systems Air Force Office of Scientific Research (AFOSR), US Programs: Hypersonics and Turbulence; Flow Control and Aeroelasticity European Office of Aerospace Research and Development (EOARD) of the AFOSR, UK Programs: Aeronautical Sciences Department of Energy (DOE), USA, DOE Office of Science US Department of Energy Lawrence Livermore National Laboratory (LLNL), USA Programs: National Ignition Facility; Fusion Energy US Department of Energy Los Alamos National Laboratory (LANL), USA US Department of Energy Argonne National Laboratory (ANL), USA Commissariat à l'Energie Atomique (CEA), France Institute for Laser Engineering (ILE), Japan The University of Chicago, USA ASC Alliance Center for Astrophysical Thermonuclear Flashes, USA Photron (Europe) Ltd, UK and thank them for making this event possible. We express our gratitude for the help with the Conference Program to the members of the Scientific Advisory Committee: S I Abarzhi (University of Chicago, USA) Y Aglitskiy (Science Applications International Corporation, USA) H Azechi (Institute for Laser Engineering, Osaka, Japan) M J Andrews (Los Alamos National Laboratory, USA) S I Anisimov (Landau Institute for Theoretical Physics, Russia) E Bodenschatz (Max Plank Institute for Dynamics and Self-Organization, Germany) F Cattaneo (University of Chicago, USA) P Cvitanović (Georgia Institute of Technology, USA) S Cowley (Imperial College, UK) S Dalziel (DAMTP, University of Cambridge, UK) W S Don (Brown University, USA) R Ecke (Los Alamos National Laboratory, USA) H J Fernando (Arizona State University, USA) I Foster (University of Chicago, USA) S Gauthier (Commissariat à l'Energie Atomique, France) G A Glatzmaier (University of California at Santa Cruz, USA) J Glimm (State University of New York at Stony Brook, USA) W A Goddard III (California Institute of Technology, USA) J Jimenez (Universidad Politecnica de Madrid, Spain) L P Kadanoff (The University of Chicago, USA) D Q Lamb (The University of Chicago, USA) D P Lathrop (University of Maryland, USA) S Lebedev (Imperial College, UK) P Manneville (École Polytechnique, France) D I Meiron (California Institute of Technology, USA) P Moin (Stanford University, USA) A Nepomnyashchy (Technion, Israel) J Niemela (International Center for Theoretical Physics, Italy) K Nishihara (Institute for Laser Engineering, Osaka, Japan) S S Orlov (Stanford University, USA) S A Orszag (Yale University, USA) E Ott (University of Maryland, USA) N Peters (RWTH Aachen University, Germany) S B Pope (Cornell, USA) A Pouquet (University Corporation for Atmospheric Research, USA) B A Remington (Lawrence Livermore National Laboratory, USA) R Rosner (Argonne National Laboratory and University of Chicago, USA) A J Schmitt (Naval Research Laboratory, USA) C -W Shu (Brown University, USA) K R Sreenivasan (International Centre for Theoretical Physics, Italy) E Tadmor (University of Maryland, USA) Y C F Thio (US Department of Energy) A L Velikovich (Naval Research Laboratory, USA) V Yakhot (Boston University, USA) P K Yeung (Georgia Institute of Technology, USA) F A Williams (University of California at San Diego, USA) E Zweibel (University of Wisconsin, USA). We deeply appreciate the work of the Selection Committee for applications for the Advanced School: S Gauthier (Commissariat à l'Energie Atomique, France) C J Keane (Lawrence Livermore National Laboratory, USA) J Niemela (International Center for Theoretical Physics, Italy) S S Orlov (Stanford University, USA) A L Velikovich (Naval Research Laboratory, USA) and thank the members of the Committee for the award 'Turbulent Mixing and Beyond for Youth': S I Abarzhi (University of Chicago, USA) M J Andrews (Los Alamos National Laboratory, USA) P Cvitanović (Georgia Institute of Technology, USA) S Gauthier (Commissariat à l'Energie Atomique, France) C J Keane (Lawrence Livermore National Laboratory, USA) S Lebedev (Imperial College, UK) J Niemela (International Center for Theoretical Physics, Italy) S S Orlov (Stanford University, USA) A Pouquet (University Corporation for Atmospheric Research, USA) K R Sreenivasan (International Centre for Theoretical Physics, Italy) A L Velikovich (Naval Research Laboratory, USA) We would like to thank all the authors and the referees for their contributions to this Topical Issue and for offering their expertise, time and effort. The readers are cordially invited to take a look at this Topical Issue for information on the frontiers of theoretical, numerical and experimental research, and state-of-the-art technology. The Organizing Committee hopes the TMB Conference will serve to advance the state-of-the-art in understanding of fundamental physical properties of non-equilibrium turbulent processes and will have an impact on predictive modeling capabilities, physical description and, ultimately, control of these complex processes. Welcome to the Topical Issue 'Turbulent Mixing and Beyond', TMB-2009.

Quantum key distribution with hacking countermeasures and long term field trial.

PubMed

Dixon, A R; Dynes, J F; Lucamarini, M; Fröhlich, B; Sharpe, A W; Plews, A; Tam, W; Yuan, Z L; Tanizawa, Y; Sato, H; Kawamura, S; Fujiwara, M; Sasaki, M; Shields, A J

2017-05-16

Quantum key distribution's (QKD's) central and unique claim is information theoretic security. However there is an increasing understanding that the security of a QKD system relies not only on theoretical security proofs, but also on how closely the physical system matches the theoretical models and prevents attacks due to discrepancies. These side channel or hacking attacks exploit physical devices which do not necessarily behave precisely as the theory expects. As such there is a need for QKD systems to be demonstrated to provide security both in the theoretical and physical implementation. We report here a QKD system designed with this goal in mind, providing a more resilient target against possible hacking attacks including Trojan horse, detector blinding, phase randomisation and photon number splitting attacks. The QKD system was installed into a 45 km link of a metropolitan telecom network for a 2.5 month period, during which time the system operated continuously and distributed 1.33 Tbits of secure key data with a stable secure key rate over 200 kbit/s. In addition security is demonstrated against coherent attacks that are more general than the collective class of attacks usually considered.

Information Theory - The Bridge Connecting Bounded Rational Game Theory and Statistical Physics

NASA Technical Reports Server (NTRS)

Wolpert, David H.

2005-01-01

A long-running difficulty with conventional game theory has been how to modify it to accommodate the bounded rationality of all red-world players. A recurring issue in statistical physics is how best to approximate joint probability distributions with decoupled (and therefore far more tractable) distributions. This paper shows that the same information theoretic mathematical structure, known as Product Distribution (PD) theory, addresses both issues. In this, PD theory not only provides a principle formulation of bounded rationality and a set of new types of mean field theory in statistical physics; it also shows that those topics are fundamentally one and the same.

Conference: Statistical Physics and Biological Information

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gross, David J.; Hwa, Terence

OAK B188 In the spring of 2001, the Institute for Theoretical Physics ran a 6 month scientific program on Statistical Physics and Biological Information. This program was organized by Walter Fitch (UC Irvine), Terence Hwa (UC San Diego), Luca Peliti (University Federico II), Naples Gary Stormo (Washington University School of Medicine) and Chao Tang (NEC). Overall scientific supervision was provided by David Gross, Director, ITP. The ITP has an online conference/program proceeding which consists of audio and transparencies of almost all of the talks held during this program. Over 100 talks are available on the site at http://online.kitp.ucsb.edu/online/infobio01/.

Application of Intervention Mapping to the Development of a Complex Physical Therapist Intervention.

PubMed

Jones, Taryn M; Dear, Blake F; Hush, Julia M; Titov, Nickolai; Dean, Catherine M

2016-12-01

Physical therapist interventions, such as those designed to change physical activity behavior, are often complex and multifaceted. In order to facilitate rigorous evaluation and implementation of these complex interventions into clinical practice, the development process must be comprehensive, systematic, and transparent, with a sound theoretical basis. Intervention Mapping is designed to guide an iterative and problem-focused approach to the development of complex interventions. The purpose of this case report is to demonstrate the application of an Intervention Mapping approach to the development of a complex physical therapist intervention, a remote self-management program aimed at increasing physical activity after acquired brain injury. Intervention Mapping consists of 6 steps to guide the development of complex interventions: (1) needs assessment; (2) identification of outcomes, performance objectives, and change objectives; (3) selection of theory-based intervention methods and practical applications; (4) organization of methods and applications into an intervention program; (5) creation of an implementation plan; and (6) generation of an evaluation plan. The rationale and detailed description of this process are presented using an example of the development of a novel and complex physical therapist intervention, myMoves-a program designed to help individuals with an acquired brain injury to change their physical activity behavior. The Intervention Mapping framework may be useful in the development of complex physical therapist interventions, ensuring the development is comprehensive, systematic, and thorough, with a sound theoretical basis. This process facilitates translation into clinical practice and allows for greater confidence and transparency when the program efficacy is investigated. © 2016 American Physical Therapy Association.

Functional Assessment for Human-Computer Interaction: A Method for Quantifying Physical Functional Capabilities for Information Technology Users

ERIC Educational Resources Information Center

Price, Kathleen J.

2011-01-01

The use of information technology is a vital part of everyday life, but for a person with functional impairments, technology interaction may be difficult at best. Information technology is commonly designed to meet the needs of a theoretical "normal" user. However, there is no such thing as a "normal" user. A user's capabilities will vary over…

Interaction-induced decay of a heteronuclear two-atom system

PubMed Central

Xu, Peng; Yang, Jiaheng; Liu, Min; He, Xiaodong; Zeng, Yong; Wang, Kunpeng; Wang, Jin; Papoular, D. J.; Shlyapnikov, G. V.; Zhan, Mingsheng

2015-01-01

Two-atom systems in small traps are of fundamental interest for understanding the role of interactions in degenerate cold gases and for the creation of quantum gates in quantum information processing with single-atom traps. One of the key quantities is the inelastic relaxation (decay) time when one of the atoms or both are in a higher hyperfine state. Here we measure this quantity in a heteronuclear system of 87Rb and 85Rb in a micro optical trap and demonstrate experimentally and theoretically the presence of both fast and slow relaxation processes, depending on the choice of the initial hyperfine states. This experimental method allows us to single out a particular relaxation process thus provides an extremely clean platform for collisional physics studies. Our results have also implications for engineering of quantum states via controlled collisions and creation of two-qubit quantum gates. PMID:26199051

An integrated organisation-wide data quality management and information governance framework: theoretical underpinnings.

PubMed

Liaw, Siaw-Teng; Pearce, Christopher; Liyanage, Harshana; Liaw, Gladys S S; de Lusignan, Simon

2014-01-01

Increasing investment in eHealth aims to improve cost effectiveness and safety of care. Data extraction and aggregation can create new data products to improve professional practice and provide feedback to improve the quality of source data. A previous systematic review concluded that locally relevant clinical indicators and use of clinical record systems could support clinical governance. We aimed to extend and update the review with a theoretical framework. We searched PubMed, Medline, Web of Science, ABI Inform (Proquest) and Business Source Premier (EBSCO) using the terms curation, information ecosystem, data quality management (DQM), data governance, information governance (IG) and data stewardship. We focused on and analysed the scope of DQM and IG processes, theoretical frameworks, and determinants of the processing, quality assurance, presentation and sharing of data across the enterprise. There are good theoretical reasons for integrated governance, but there is variable alignment of DQM, IG and health system objectives across the health enterprise. Ethical constraints exist that require health information ecosystems to process data in ways that are aligned with improving health and system efficiency and ensuring patient safety. Despite an increasingly 'big-data' environment, DQM and IG in health services are still fragmented across the data production cycle. We extend current work on DQM and IG with a theoretical framework for integrated IG across the data cycle. The dimensions of this theory-based framework would require testing with qualitative and quantitative studies to examine the applicability and utility, along with an evaluation of its impact on data quality across the health enterprise.

The Role of Reader Characteristics in Processing and Learning from Informational Text

ERIC Educational Resources Information Center

Fox, Emily

2009-01-01

This article considers the role of reader characteristics in processing and learning from informational text, as revealed in think-aloud research. A theoretical framework for relevant aspects of readers' processing and products was developed. These relevant aspects included three attentional foci for processing (comprehension, monitoring, and…

High energy physics at UC Riverside

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-07-01

This report discusses progress made for the following two tasks: experimental high energy physics, Task A, and theoretical high energy physics, Task B. Task A1 covers hadron collider physics. Information for Task A1 includes: personnel/talks/publications; D0: proton-antiproton interactions at 2 TeV; SDC: proton-proton interactions at 40 TeV; computing facilities; equipment needs; and budget notes. The physics program of Task A2 has been the systematic study of leptons and hadrons. Information covered for Task A2 includes: personnel/talks/publications; OPAL at LEP; OPAL at LEP200; CMS at LHC; the RD5 experiment; LSND at LAMPF; and budget notes. The research activities of the Theorymore » Group are briefly discussed and a list of completed or published papers for this period is given.« less

Theoretical and experimental study of a new algorithm for factoring numbers

NASA Astrophysics Data System (ADS)

Tamma, Vincenzo

The security of codes, for example in credit card and government information, relies on the fact that the factorization of a large integer N is a rather costly process on a classical digital computer. Such a security is endangered by Shor's algorithm which employs entangled quantum systems to find, with a polynomial number of resources, the period of a function which is connected with the factors of N. We can surely expect a possible future realization of such a method for large numbers, but so far the period of Shor's function has been only computed for the number 15. Inspired by Shor's idea, our work aims to methods of factorization based on the periodicity measurement of a given continuous periodic "factoring function" which is physically implementable using an analogue computer. In particular, we have focused on both the theoretical and the experimental analysis of Gauss sums with continuous arguments leading to a new factorization algorithm. The procedure allows, for the first time, to factor several numbers by measuring the periodicity of Gauss sums performing first-order "factoring" interfer ence processes. We experimentally implemented this idea by exploiting polychromatic optical interference in the visible range with a multi-path interferometer, and achieved the factorization of seven digit numbers. The physical principle behind this "factoring" interference procedure can be potentially exploited also on entangled systems, as multi-photon entangled states, in order to achieve a polynomial scaling in the number of resources.

Conceptual models of information processing

NASA Technical Reports Server (NTRS)

Stewart, L. J.

1983-01-01

The conceptual information processing issues are examined. Human information processing is defined as an active cognitive process that is analogous to a system. It is the flow and transformation of information within a human. The human is viewed as an active information seeker who is constantly receiving, processing, and acting upon the surrounding environmental stimuli. Human information processing models are conceptual representations of cognitive behaviors. Models of information processing are useful in representing the different theoretical positions and in attempting to define the limits and capabilities of human memory. It is concluded that an understanding of conceptual human information processing models and their applications to systems design leads to a better human factors approach.

Mujeres Fuertes y Corazones Saludables: adaptation of the StrongWomen -healthy hearts program for rural Latinas using an intervention mapping approach.

PubMed

Perry, Cynthia K; McCalmont, Jean C; Ward, Judy P; Menelas, Hannah-Dulya K; Jackson, Christie; De Witz, Jazmyne R; Solanki, Emma; Seguin, Rebecca A

2017-12-28

To describe our use of intervention mapping as a systematic method to adapt an evidence-based physical activity and nutrition program to reflect the needs of rural Latinas. An intervention mapping process involving six steps guided the adaptation of an evidence based physical activity and nutrition program, using a community-based participatory research approach. We partnered with a community advisory board of rural Latinas throughout the adaptation process. A needs assessment and logic models were used to ascertain which program was the best fit for adaptation. Once identified, we collaborated with one of the developers of the original program (StrongWomen - Healthy Hearts) during the adaptation process. First, essential theoretical methods and program elements were identified, and additional elements were added or adapted. Next, we reviewed and made changes to reflect the community and cultural context of the practical applications, intervention strategies, program curriculum, materials, and participant information. Finally, we planned for the implementation and evaluation of the adapted program, Mujeres Fuertes y Corazones Saludables, within the context of the rural community. A pilot study will be conducted with overweight, sedentary, middle-aged, Spanish-speaking Latinas. Outcome measures will assess change in weight, physical fitness, physical activity, and nutrition behavior. The intervention mapping process was feasible and provided a systematic approach to balance fit and fidelity in the adaptation of an evidence-based program. Collaboration with community members ensured that the components of the curriculum that were adapted were culturally appropriate and relevant within the local community context.

Biofield Science: Current Physics Perspectives

PubMed Central

Chevalier, Gaétan; Chopra, Deepak; Hubacher, John; Kak, Subhash; Theise, Neil D.

2015-01-01

This article briefly reviews the biofield hypothesis and its scientific literature. Evidence for the existence of the biofield now exists, and current theoretical foundations are now being developed. A review of the biofield and related topics from the perspective of physical science is needed to identify a common body of knowledge and evaluate possible underlying principles of origin of the biofield. The properties of such a field could be based on electromagnetic fields, coherent states, biophotons, quantum and quantum-like processes, and ultimately the quantum vacuum. Given this evidence, we intend to inquire and discuss how the existence of the biofield challenges reductionist approaches and presents its own challenges regarding the origin and source of the biofield, the specific evidence for its existence, its relation to biology, and last but not least, how it may inform an integrated understanding of consciousness and the living universe. PMID:26665039

The physics of heavy quark distributions in hadrons: Collider tests

NASA Astrophysics Data System (ADS)

Brodsky, S. J.; Bednyakov, V. A.; Lykasov, G. I.; Smiesko, J.; Tokar, S.

2017-03-01

We present a review of the current understanding of the heavy quark distributions in the nucleon and their impact on collider physics. The origin of strange, charm and bottom quark pairs at high light-front (LF) momentum fractions in hadron wavefunction-the "intrinsic" quarks, is reviewed. The determination of heavy-quark parton distribution functions (PDFs) is particularly significant for the analysis of hard processes at LHC energies. We show that a careful study of the inclusive production of open charm and the production of γ / Z / W particles, accompanied by the heavy jets at large transverse momenta can give essential information on the intrinsic heavy quark (IQ) distributions. We also focus on the theoretical predictions concerning other observables which are very sensitive to the intrinsic charm contribution to PDFs including Higgs production at high xF and novel fixed target measurements which can be tested at the LHC.

The physics of heavy quark distributions in hadrons: Collider tests

DOE PAGES

Brodsky, S. J.; Bednyakov, V. A.; Lykasov, G. I.; ...

2016-12-18

Here, we present a review of the current understanding of the heavy quark distributions in the nucleon and their impact on collider physics. The origin of strange, charm and bottom quark pairs at high light-front (LF) momentum fractions in hadron wavefunction—the “intrinsic” quarks, is reviewed. The determination of heavy-quark parton distribution functions (PDFs) is particularly significant for the analysis of hard processes at LHC energies. We show that a careful study of the inclusive production of open charm and the production of γ/Z/W particles, accompanied by the heavy jets at large transverse momenta can give essential information on the intrinsicmore » heavy quark (IQ) distributions. We also focus on the theoretical predictions concerning other observables which are very sensitive to the intrinsic charm contribution to PDFs including Higgs production at high x F and novel fixed target measurements which can be tested at the LHC.« less

High-fidelity plasma codes for burn physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cooley, James; Graziani, Frank; Marinak, Marty

Accurate predictions of equation of state (EOS), ionic and electronic transport properties are of critical importance for high-energy-density plasma science. Transport coefficients inform radiation-hydrodynamic codes and impact diagnostic interpretation, which in turn impacts our understanding of the development of instabilities, the overall energy balance of burning plasmas, and the efficacy of self-heating from charged-particle stopping. Important processes include thermal and electrical conduction, electron-ion coupling, inter-diffusion, ion viscosity, and charged particle stopping. However, uncertainties in these coefficients are not well established. Fundamental plasma science codes, also called high-fidelity plasma codes, are a relatively recent computational tool that augments both experimental datamore » and theoretical foundations of transport coefficients. This paper addresses the current status of HFPC codes and their future development, and the potential impact they play in improving the predictive capability of the multi-physics hydrodynamic codes used in HED design.« less

Transient Dissipation and Structural Costs of Physical Information Transduction

NASA Astrophysics Data System (ADS)

Boyd, Alexander B.; Mandal, Dibyendu; Riechers, Paul M.; Crutchfield, James P.

2017-06-01

A central result that arose in applying information theory to the stochastic thermodynamics of nonlinear dynamical systems is the information-processing second law (IPSL): the physical entropy of the Universe can decrease if compensated by the Shannon-Kolmogorov-Sinai entropy change of appropriate information-carrying degrees of freedom. In particular, the asymptotic-rate IPSL precisely delineates the thermodynamic functioning of autonomous Maxwellian demons and information engines. How do these systems begin to function as engines, Landauer erasers, and error correctors? We identify a minimal, and thus inescapable, transient dissipation of physical information processing, which is not captured by asymptotic rates, but is critical to adaptive thermodynamic processes such as those found in biological systems. A component of transient dissipation, we also identify an implementation-dependent cost that varies from one physical substrate to another for the same information processing task. Applying these results to producing structured patterns from a structureless information reservoir, we show that "retrodictive" generators achieve the minimal costs. The results establish the thermodynamic toll imposed by a physical system's structure as it comes to optimally transduce information.

[Verbal patient information through nurses--a case of stroke patients].

PubMed

Christmann, Elli; Holle, Regina; Schüssler, Dörte; Beier, Jutta; Dassen, Theo

2004-06-01

The article represents results of a theoretical work in the field of nursing education, with the topic: Verbal Patient Information through Nurses--A Case of Stroke Patients. The literature review and analysis show that there is a shortage in (stroke) patient information generally and a lack of successful concepts and strategies for the verbal (stroke) patient information through nurses in hospitals. The authors have developed a theoretical basis for health information as a nursing intervention and this represents a model of health information as a "communicational teach-and-learn process", which is of general application to all patients. The health information takes place as a separate nursing intervention within a non-public, face-to-face communication situation and in the steps-model of the nursing process. Health information is seen as a learning process for patients and nurses too. We consider learning as information production (constructivism) and information processing (cognitivism). Both processes are influenced by different factors and the illness-situation of patients, personality information content and the environment. For a successful health information output, it is necessary to take care of these aspects and this can be realized through a constructivational understanding of didactics. There is a need for an evaluation study to prove our concept of health information.

Composing Models of Geographic Physical Processes

NASA Astrophysics Data System (ADS)

Hofer, Barbara; Frank, Andrew U.

Processes are central for geographic information science; yet geographic information systems (GIS) lack capabilities to represent process related information. A prerequisite to including processes in GIS software is a general method to describe geographic processes independently of application disciplines. This paper presents such a method, namely a process description language. The vocabulary of the process description language is derived formally from mathematical models. Physical processes in geography can be described in two equivalent languages: partial differential equations or partial difference equations, where the latter can be shown graphically and used as a method for application specialists to enter their process models. The vocabulary of the process description language comprises components for describing the general behavior of prototypical geographic physical processes. These process components can be composed by basic models of geographic physical processes, which is shown by means of an example.

Quantum information is physical

NASA Astrophysics Data System (ADS)

DiVincenzo, D. P.; Loss, D.

1998-03-01

We discuss a few current developments in the use of quantum mechanically coherent systems for information processing. In each of these developments, Rolf Landauer has played a crucial role in nudging us, and other workers in the field, into asking the right questions, some of which we have been lucky enough to answer. A general overview of the key ideas of quantum error correction is given. We discuss how quantum entanglement is the key to protecting quantum states from decoherence in a manner which, in a theoretical sense, is as effective as the protection of digital data from bit noise. We also discuss five general criteria which must be satisfied to implement a quantum computer in the laboratory, and we illustrate the application of these criteria by discussing our ideas for creating a quantum computer out of the spin states of coupled quantum dots.

My 50 years of research in particle physics.

PubMed

Sugawara, Hirotaka

2010-01-01

Some of my work of the last 50 years in the field of theoretical particle physics is described with particular emphasis on the motivation, the process of investigation, relationship to the work of others, and its impact. My judgment is unavoidably subjective, although I do present the comments of other researchers as much as possible.

Social Processes of Health and Physical Education Teachers' Identity Formation: Reproducing and Changing Culture

ERIC Educational Resources Information Center

Sirna, K.; Tinning, R.; Rossi, T.

2010-01-01

This paper examines Initial Teacher Education students' experiences of participation in health and physical education (HPE) subject department offices and the impact on their understandings and identity formation. Pierre Bourdieu's concepts of habitus, field, and practice along with Wenger's communities of practice form the theoretical frame used…

Activity matters: a web-based resource to enable people with multiple sclerosis to become more active.

PubMed

Casey, Blathin; Coote, Susan; Byrne, Molly

2018-03-27

Increasing physical activity (PA) through exercise is associated with improvements in many of the symptoms associated with multiple sclerosis (MS) such as fatigue, strength, balance, and mobility. Despite this, people with MS remain largely inactive. Interventions that are grounded in theory and that aim to change PA behavior need to be developed. The purpose of this study was to describe the development process of a web-based resource, namely, "Activity Matters," to enable people with MS to become more active. Development of the "Activity Matters" online intervention was guided by the UK's Medical Research Council (MRC) framework for the development and evaluation of complex interventions and the behavior change wheel (BCW). Seven sources of data were used to inform the process and were mapped on to both the MRC and BCW frameworks. The intervention is theoretically based, and constructs including knowledge, memory, attention and decision processes, skills, social influences, environmental context and resources, beliefs about capabilities, beliefs about consequences, goals, and emotions were recognized as important. "Activity Matters" is the first MS PA intervention to be developed using the theoretical approach outlined by the BCW and MRC complex interventions frameworks. The next phase of this work is to test the usability, acceptability, and preliminary effectiveness of "Activity Matters" among people with MS.

Syllabus Computer in Astronomy

NASA Astrophysics Data System (ADS)

Hojaev, Alisher S.

2015-08-01

One of the most important and actual subjects and training courses in the curricula for undergraduate level students at the National university of Uzbekistan is ‘Computer Methods in Astronomy’. It covers two semesters and includes both lecture and practice classes. Based on the long term experience we prepared the tutorial for students which contain the description of modern computer applications in astronomy.The main directions of computer application in field of astronomy briefly as follows:1) Automating the process of observation, data acquisition and processing2) Create and store databases (the results of observations, experiments and theoretical calculations) their generalization, classification and cataloging, working with large databases3) The decisions of the theoretical problems (physical modeling, mathematical modeling of astronomical objects and phenomena, derivation of model parameters to obtain a solution of the corresponding equations, numerical simulations), appropriate software creation4) The utilization in the educational process (e-text books, presentations, virtual labs, remote education, testing), amateur astronomy and popularization of the science5) The use as a means of communication and data transfer, research result presenting and dissemination (web-journals), the creation of a virtual information system (local and global computer networks).During the classes the special attention is drawn on the practical training and individual work of students including the independent one.

Information Diffusion in Facebook-Like Social Networks Under Information Overload

NASA Astrophysics Data System (ADS)

Li, Pei; Xing, Kai; Wang, Dapeng; Zhang, Xin; Wang, Hui

2013-07-01

Research on social networks has received remarkable attention, since many people use social networks to broadcast information and stay connected with their friends. However, due to the information overload in social networks, it becomes increasingly difficult for users to find useful information. This paper takes Facebook-like social networks into account, and models the process of information diffusion under information overload. The term view scope is introduced to model the user information-processing capability under information overload, and the average number of times a message appears in view scopes after it is generated is proposed to characterize the information diffusion efficiency. Through theoretical analysis, we find that factors such as network structure and view scope number have no impact on the information diffusion efficiency, which is a surprising result. To verify the results, we conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly.

An Informative Interpretation of Decision Theory: The Information Theoretic Basis for Signal-to-Noise Ratio and Log Likelihood Ratio

DOE PAGES

Polcari, J.

2013-08-16

The signal processing concept of signal-to-noise ratio (SNR), in its role as a performance measure, is recast within the more general context of information theory, leading to a series of useful insights. Establishing generalized SNR (GSNR) as a rigorous information theoretic measure inherent in any set of observations significantly strengthens its quantitative performance pedigree while simultaneously providing a specific definition under general conditions. This directly leads to consideration of the log likelihood ratio (LLR): first, as the simplest possible information-preserving transformation (i.e., signal processing algorithm) and subsequently, as an absolute, comparable measure of information for any specific observation exemplar. Furthermore,more » the information accounting methodology that results permits practical use of both GSNR and LLR as diagnostic scalar performance measurements, directly comparable across alternative system/algorithm designs, applicable at any tap point within any processing string, in a form that is also comparable with the inherent performance bounds due to information conservation.« less

Theoretical foundations for information representation and constraint specification

NASA Technical Reports Server (NTRS)

Menzel, Christopher P.; Mayer, Richard J.

1991-01-01

Research accomplished at the Knowledge Based Systems Laboratory of the Department of Industrial Engineering at Texas A&M University is described. Outlined here are the theoretical foundations necessary to construct a Neutral Information Representation Scheme (NIRS), which will allow for automated data transfer and translation between model languages, procedural programming languages, database languages, transaction and process languages, and knowledge representation and reasoning control languages for information system specification.

Reflections on the information paradigm in quantum and gravitational physics

NASA Astrophysics Data System (ADS)

Andres Höhn, Philipp

2017-08-01

We reflect on the information paradigm in quantum and gravitational physics and on how it may assist us in approaching quantum gravity. We begin by arguing, using a reconstruction of its formalism, that quantum theory can be regarded as a universal framework governing an observer’s acquisition of information from physical systems taken as information carriers. We continue by observing that the structure of spacetime is encoded in the communication relations among observers and more generally the information flow in spacetime. Combining these insights with an information-theoretic Machian view, we argue that the quantum architecture of spacetime can operationally be viewed as a locally finite network of degrees of freedom exchanging information. An advantage - and simultaneous limitation - of an informational perspective is its quasi-universality, i.e. quasi-independence of the precise physical incarnation of the underlying degrees of freedom. This suggests to exploit these informational insights to develop a largely microphysics independent top-down approach to quantum gravity to complement extant bottom-up approaches by closing the scale gap between the unknown Planck scale physics and the familiar physics of quantum (field) theory and general relativity systematically from two sides. While some ideas have been pronounced before in similar guise and others are speculative, the way they are strung together and justified is new and supports approaches attempting to derive emergent spacetime structures from correlations of quantum degrees of freedom.

Small strain multiphase-field model accounting for configurational forces and mechanical jump conditions

NASA Astrophysics Data System (ADS)

Schneider, Daniel; Schoof, Ephraim; Tschukin, Oleg; Reiter, Andreas; Herrmann, Christoph; Schwab, Felix; Selzer, Michael; Nestler, Britta

2018-03-01

Computational models based on the phase-field method have become an essential tool in material science and physics in order to investigate materials with complex microstructures. The models typically operate on a mesoscopic length scale resolving structural changes of the material and provide valuable information about the evolution of microstructures and mechanical property relations. For many interesting and important phenomena, such as martensitic phase transformation, mechanical driving forces play an important role in the evolution of microstructures. In order to investigate such physical processes, an accurate calculation of the stresses and the strain energy in the transition region is indispensable. We recall a multiphase-field elasticity model based on the force balance and the Hadamard jump condition at the interface. We show the quantitative characteristics of the model by comparing the stresses, strains and configurational forces with theoretical predictions in two-phase cases and with results from sharp interface calculations in a multiphase case. As an application, we choose the martensitic phase transformation process in multigrain systems and demonstrate the influence of the local homogenization scheme within the transition regions on the resulting microstructures.

Information Fluxes as Concept for Categorizations of Life

NASA Astrophysics Data System (ADS)

Hildenbrand, Georg; Hausmann, M.

2012-05-01

Definitions of life are controversially discussed; however, they are mostly depending on bio- evolutionary driven arguments. Here, we propose a systematic, theoretical approach to the question what life is, by categorization and classification of different levels of life. This approach is mainly based on the analysis of information flux occurring in systems being suspicious to be alive, and on the analysis of their power of environmental control. In a first step, we show that all biological definitions of life can be derived from basic physical principles of entropy (number of possible states of a thermodynamic system) and of the energy needed for controlling entropic development. In a next step we discuss how any process where information flux is generated, regardless of its materialization is defined and related to classical definitions of life. In a third step we resume the proposed classification scheme in its most basic way, looking only for existence of data storage, its processing, and its environmental control. We join inhere a short discussion how the materialization of information fluxes can take place depending on the special properties of the four basic physical forces. Having done all this we are able to give everybody a classification catalogue at hand that one can categorize the kind of life one is talking about, thus overcoming the obstacles deriving from the simple appearing question whether something is alive or not. On its most basic level as presented here, our scheme offers a categorization for fire, crystals, prions, viruses, spores, up to cells and even tardigrada and cryostases.

Information Theoretic Characterization of Physical Theories with Projective State Space

NASA Astrophysics Data System (ADS)

Zaopo, Marco

2015-08-01

Probabilistic theories are a natural framework to investigate the foundations of quantum theory and possible alternative or deeper theories. In a generic probabilistic theory, states of a physical system are represented as vectors of outcomes probabilities and state spaces are convex cones. In this picture the physics of a given theory is related to the geometric shape of the cone of states. In quantum theory, for instance, the shape of the cone of states corresponds to a projective space over complex numbers. In this paper we investigate geometric constraints on the state space of a generic theory imposed by the following information theoretic requirements: every non completely mixed state of a system is perfectly distinguishable from some other state in a single shot measurement; information capacity of physical systems is conserved under making mixtures of states. These assumptions guarantee that a generic physical system satisfies a natural principle asserting that the more a state of the system is mixed the less information can be stored in the system using that state as logical value. We show that all theories satisfying the above assumptions are such that the shape of their cones of states is that of a projective space over a generic field of numbers. Remarkably, these theories constitute generalizations of quantum theory where superposition principle holds with coefficients pertaining to a generic field of numbers in place of complex numbers. If the field of numbers is trivial and contains only one element we obtain classical theory. This result tells that superposition principle is quite common among probabilistic theories while its absence gives evidence of either classical theory or an implausible theory.

Modelling periodic structure formation on 100Cr6 steel after irradiation with femtosecond-pulsed laser beams

NASA Astrophysics Data System (ADS)

Tsibidis, George D.; Mimidis, Alexandros; Skoulas, Evangelos; Kirner, Sabrina V.; Krüger, Jörg; Bonse, Jörn; Stratakis, Emmanuel

2018-01-01

We investigate the periodic structure formation upon intense femtosecond pulsed irradiation of chrome steel (100Cr6) for linearly polarised laser beams. The underlying physical mechanism of the laser-induced periodic structures is explored, their spatial frequency is calculated and theoretical results are compared with experimental observations. The proposed theoretical model comprises estimations of electron excitation, heat transfer, relaxation processes, and hydrodynamics-related mass transport. Simulations describe the sequential formation of sub-wavelength ripples and supra-wavelength grooves. In addition, the influence of the laser wavelength on the periodicity of the structures is discussed. The proposed theoretical investigation offers a systematic methodology towards laser processing of steel surfaces with important applications.

Creative Practices Embodied, Embedded, and Enacted in Architectural Settings: Toward an Ecological Model of Creativity.

PubMed

Malinin, Laura H

2015-01-01

Memoires by eminently creative people often describe architectural spaces and qualities they believe instrumental for their creativity. However, places designed to encourage creativity have had mixed results, with some found to decrease creative productivity for users. This may be due, in part, to lack of suitable empirical theory or model to guide design strategies. Relationships between creative cognition and features of the physical environment remain largely uninvestigated in the scientific literature, despite general agreement among researchers that human cognition is physically and socially situated. This paper investigates what role architectural settings may play in creative processes by examining documented first person and biographical accounts of creativity with respect to three central theories of situated cognition. First, the embodied thesis argues that cognition encompasses both the mind and the body. Second, the embedded thesis maintains that people exploit features of the physical and social environment to increase their cognitive capabilities. Third, the enaction thesis describes cognition as dependent upon a person's interactions with the world. Common themes inform three propositions, illustrated in a new theoretical framework describing relationships between people and their architectural settings with respect to different cognitive processes of creativity. The framework is intended as a starting point toward an ecological model of creativity, which may be used to guide future creative process research and architectural design strategies to support user creative productivity.

Creative Practices Embodied, Embedded, and Enacted in Architectural Settings: Toward an Ecological Model of Creativity

PubMed Central

Malinin, Laura H.

2016-01-01

Memoires by eminently creative people often describe architectural spaces and qualities they believe instrumental for their creativity. However, places designed to encourage creativity have had mixed results, with some found to decrease creative productivity for users. This may be due, in part, to lack of suitable empirical theory or model to guide design strategies. Relationships between creative cognition and features of the physical environment remain largely uninvestigated in the scientific literature, despite general agreement among researchers that human cognition is physically and socially situated. This paper investigates what role architectural settings may play in creative processes by examining documented first person and biographical accounts of creativity with respect to three central theories of situated cognition. First, the embodied thesis argues that cognition encompasses both the mind and the body. Second, the embedded thesis maintains that people exploit features of the physical and social environment to increase their cognitive capabilities. Third, the enaction thesis describes cognition as dependent upon a person’s interactions with the world. Common themes inform three propositions, illustrated in a new theoretical framework describing relationships between people and their architectural settings with respect to different cognitive processes of creativity. The framework is intended as a starting point toward an ecological model of creativity, which may be used to guide future creative process research and architectural design strategies to support user creative productivity. PMID:26779087

Testing Theory of Planned Behavior and Neo-Socioanalytic Theory models of trait activity, industriousness, exercise social cognitions, exercise intentions, and physical activity in a representative U.S. sample.

PubMed

Vo, Phuong T; Bogg, Tim

2015-01-01

Prior research identified assorted relations between trait and social cognition models of personality and engagement in physical activity. Using a representative U.S. sample (N = 957), the goal of the present study was to test two alternative structural models of the relationships among the extraversion-related facet of activity, the conscientiousness-related facet of industriousness, social cognitions from the Theory of Planned Behavior (perceived behavioral control, affective attitudes, subjective norms, intentions), Social Cognitive Theory (self-efficacy, outcome expectancies), and the Transtheoretical Model (behavioral processes of change), and engagement in physical activity. Path analyses with bootstrapping procedures were used to model direct and indirect effects of trait and social cognition constructs on physical activity through two distinct frameworks - the Theory of Planned Behavior and Neo-Socioanalytic Theory. While both models showed good internal fit, comparative model information criteria showed the Theory-of-Planned-Behavior-informed model provided a better fit. In the model, social cognitions fully mediated the relationships from the activity facet and industriousness to intentions for and engagement in physical activity, such that the relationships were primarily maintained by positive affective evaluations, positive expected outcomes, and confidence in overcoming barriers related to physical activity engagement. The resultant model - termed the Disposition-Belief-Motivation model- is proposed as a useful framework for organizing and integrating personality trait facets and social cognitions from various theoretical perspectives to investigate the expression of health-related behaviors, such as physical activity. Moreover, the results are discussed in terms of extending the application of the Disposition-Belief-Motivation model to longitudinal and intervention designs for physical activity engagement.

Testing Theory of Planned Behavior and Neo-Socioanalytic Theory models of trait activity, industriousness, exercise social cognitions, exercise intentions, and physical activity in a representative U.S. sample

PubMed Central

Vo, Phuong T.; Bogg, Tim

2015-01-01

Prior research identified assorted relations between trait and social cognition models of personality and engagement in physical activity. Using a representative U.S. sample (N = 957), the goal of the present study was to test two alternative structural models of the relationships among the extraversion-related facet of activity, the conscientiousness-related facet of industriousness, social cognitions from the Theory of Planned Behavior (perceived behavioral control, affective attitudes, subjective norms, intentions), Social Cognitive Theory (self-efficacy, outcome expectancies), and the Transtheoretical Model (behavioral processes of change), and engagement in physical activity. Path analyses with bootstrapping procedures were used to model direct and indirect effects of trait and social cognition constructs on physical activity through two distinct frameworks – the Theory of Planned Behavior and Neo-Socioanalytic Theory. While both models showed good internal fit, comparative model information criteria showed the Theory-of-Planned-Behavior-informed model provided a better fit. In the model, social cognitions fully mediated the relationships from the activity facet and industriousness to intentions for and engagement in physical activity, such that the relationships were primarily maintained by positive affective evaluations, positive expected outcomes, and confidence in overcoming barriers related to physical activity engagement. The resultant model – termed the Disposition-Belief-Motivation model– is proposed as a useful framework for organizing and integrating personality trait facets and social cognitions from various theoretical perspectives to investigate the expression of health-related behaviors, such as physical activity. Moreover, the results are discussed in terms of extending the application of the Disposition-Belief-Motivation model to longitudinal and intervention designs for physical activity engagement. PMID:26300811

Effects of Buoyancy on Laminar, Transitional, and Turbulent Gas Jet Diffusion Flames

NASA Technical Reports Server (NTRS)

Bahadori, M. Yousef; Stocker, Dennis P.; Vaughan, David F.; Zhou, Liming; Edelman, Raymond B.

1993-01-01

Gas jet diffusion flames have been a subject of research for many years. However, a better understanding of the physical and chemical phenomena occurring in these flames is still needed, and, while the effects of gravity on the burning process have been observed, the basic mechanisms responsible for these changes have yet to be determined. The fundamental mechanisms that control the combustion process are in general coupled and quite complicated. These include mixing, radiation, kinetics, soot formation and disposition, inertia, diffusion, and viscous effects. In order to understand the mechanisms controlling a fire, laboratory-scale laminar and turbulent gas-jet diffusion flames have been extensively studied, which have provided important information in relation to the physico-chemical processes occurring in flames. However, turbulent flames are not fully understood and their understanding requires more fundamental studies of laminar diffusion flames in which the interplay of transport phenomena and chemical kinetics is more tractable. But even this basic, relatively simple flame is not completely characterized in relation to soot formation, radiation, diffusion, and kinetics. Therefore, gaining an understanding of laminar flames is essential to the understanding of turbulent flames, and particularly fires, in which the same basic phenomena occur. In order to improve and verify the theoretical models essential to the interpretation of data, the complexity and degree of coupling of the controlling mechanisms must be reduced. If gravity is isolated, the complication of buoyancy-induced convection would be removed from the problem. In addition, buoyant convection in normal gravity masks the effects of other controlling parameters on the flame. Therefore, the combination of normal-gravity and microgravity data would provide the information, both theoretical and experimental, to improve our understanding of diffusion flames in general, and the effects of gravity on the burning process in particular.

Effect of drop size on the impact thermodynamics for supercooled large droplet in aircraft icing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Chen; Liu, Hong, E-mail: hongliu@sjtu.edu.cn

Supercooled large droplet (SLD), which can cause abnormal icing, is a well-known issue in aerospace engineering. Although efforts have been exerted to understand large droplet impact dynamics and the supercooled feature in the film/substrate interface, respectively, the thermodynamic effect during the SLD impact process has not received sufficient attention. This work conducts experimental studies to determine the effects of drop size on the thermodynamics for supercooled large droplet impingement. Through phenomenological reproduction, the rapid-freezing characteristics are observed in diameters of 400, 800, and 1300 μm. The experimental analysis provides information on the maximum spreading rate and the shrinkage rate ofmore » the drop, the supercooled diffusive rate, and the freezing time. A physical explanation of this unsteady heat transfer process is proposed theoretically, which indicates that the drop size is a critical factor influencing the supercooled heat exchange and effective heat transfer duration between the film/substrate interface. On the basis of the present experimental data and theoretical analysis, an impinging heating model is developed and applied to typical SLD cases. The model behaves as anticipated, which underlines the wide applicability to SLD icing problems in related fields.« less

Consolidation of Bimetallic Nanosized Particles and Formation of Nanocomposites Depending on Conditions of Shock Wave Compaction

NASA Astrophysics Data System (ADS)

Vorozhtsov, S. A.; Kudryashova, O. B.; Lerner, M. I.; Vorozhtsov, A. B.; Khrustalyov, A. P.; Pervikov, A. V.

2017-11-01

The authors consider and evaluate the physical parameters and regularities of the process of consolidation of Fe-Cu, Cu-Nb, Ag-Ni, Fe-Pb nanoparticles when creating composite materials by means of shock wave compaction. As a result of theoretical consideration of explosive compaction process, researchers established and discussed the physical process conditions, established a number of threshold pressure values corresponding to different target indicators of the state of the compact. The time of shock wave impact on powders for powder consolidation was estimated.

The physics of interstellar shock waves

NASA Technical Reports Server (NTRS)

Shull, J. Michael; Draine, Bruce T.

1987-01-01

This review discusses the observations and theoretical models of interstellar shock waves, in both diffuse cloud and molecular cloud environments. It summarizes the relevant gas dynamics, atomic, molecular and grain processes, radiative transfer, and physics of radiative and magnetic precursors in shock models. It then describes the importance of shocks for observations, diagnostics, and global interstellar dynamics. It concludes with current research problems and data needs for atomic, molecular and grain physics.

Learning Pathways, Learning Progression--The Process Matters: An Interview with Prof. Hans Niedderer about His Work as a Physics Education Researcher in Germany

ERIC Educational Resources Information Center

Kulgemeyer, Christoph

2014-01-01

Hans Niedderer has contributed a lot to German physics education research. His work includes quantitative and qualitative studies about topics like the learning of physics concepts or the history and philosophy of science in science teaching, he has worked on theoretical issues as well as on textbooks. But it is not only his work that is…

Physics of metabolic organization.

PubMed

Jusup, Marko; Sousa, Tânia; Domingos, Tiago; Labinac, Velimir; Marn, Nina; Wang, Zhen; Klanjšček, Tin

2017-03-01

We review the most comprehensive metabolic theory of life existing to date. A special focus is given to the thermodynamic roots of this theory and to implications that the laws of physics-such as the conservation of mass and energy-have on all life. Both the theoretical foundations and biological applications are covered. Hitherto, the foundations were more accessible to physicists or mathematicians, and the applications to biologists, causing a dichotomy in what always should have been a single body of work. To bridge the gap between the two aspects of the same theory, we (i) adhere to the theoretical formalism, (ii) try to minimize the amount of information that a reader needs to process, but also (iii) invoke examples from biology to motivate the introduction of new concepts and to justify the assumptions made, and (iv) show how the careful formalism of the general theory enables modular, self-consistent extensions that capture important features of the species and the problem in question. Perhaps the most difficult among the introduced concepts, the utilization (or mobilization) energy flow, is given particular attention in the form of an original and considerably simplified derivation. Specific examples illustrate a range of possible applications-from energy budgets of individual organisms, to population dynamics, to ecotoxicology. Copyright © 2016 Elsevier B.V. All rights reserved.

Metasurface-Enabled Remote Quantum Interference.

PubMed

Jha, Pankaj K; Ni, Xingjie; Wu, Chihhui; Wang, Yuan; Zhang, Xiang

2015-07-10

An anisotropic quantum vacuum (AQV) opens novel pathways for controlling light-matter interaction in quantum optics, condensed matter physics, etc. Here, we theoretically demonstrate a strong AQV over macroscopic distances enabled by a judiciously designed array of subwavelength-scale nanoantennas-a metasurface. We harness the phase-control ability and the polarization-dependent response of the metasurface to achieve strong anisotropy in the decay rate of a quantum emitter located over distances of hundreds of wavelengths. Such an AQV induces quantum interference among radiative decay channels in an atom with orthogonal transitions. Quantum vacuum engineering with metasurfaces holds promise for exploring new paradigms of long-range light-matter interaction for atom optics, solid-state quantum optics, quantum information processing, etc.

Prototyping manufacturing in the cloud

NASA Astrophysics Data System (ADS)

Ciortea, E. M.

2017-08-01

This paper attempts a theoretical approach to cloud systems with impacts on production systems. I call systems as cloud computing because form a relatively new concept in the field of informatics, representing an overall distributed computing services, applications, access to information and data storage without the user to know the physical location and configuration of systems. The advantages of this approach are especially computing speed and storage capacity without investment in additional configurations, synchronizing user data, data processing using web applications. The disadvantage is that it wants to identify a solution for data security, leading to mistrust users. The case study is applied to a module of the system of production, because the system is complex.

Physical Processes in the MAGO/MFT Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garanin, Sergey F; Reinovsky, Robert E.

2015-03-23

The Monograph is devoted to theoretical discussion of the physical effects, which are most significant for the alternative approach to the problem of controlled thermonuclear fusion (CTF): the MAGO/MTF approach. The book includes the description of the approach, its difference from the major CTF systems—magnetic confinement and inertial confinement systems. General physical methods of the processes simulation in this approach are considered, including plasma transport phenomena and radiation, and the theory of transverse collisionless shock waves, the surface discharges theory, important for such kind of research. Different flows and magneto-hydrodynamic plasma instabilities occurring in the frames of this approach aremore » also considered. In virtue of the general physical essence of the considered phenomena the presented results are applicable to a wide range of plasma physics and hydrodynamics processes. The book is intended for the plasma physics and hydrodynamics specialists, post-graduate students, and senior students-physicists.« less

Mindfulness and Cardiovascular Disease Risk: State of the Evidence, Plausible Mechanisms, and Theoretical Framework.

PubMed

Loucks, Eric B; Schuman-Olivier, Zev; Britton, Willoughby B; Fresco, David M; Desbordes, Gaelle; Brewer, Judson A; Fulwiler, Carl

2015-12-01

The purpose of this review is to provide (1) a synopsis on relations of mindfulness with cardiovascular disease (CVD) and major CVD risk factors, and (2) an initial consensus-based overview of mechanisms and theoretical framework by which mindfulness might influence CVD. Initial evidence, often of limited methodological quality, suggests possible impacts of mindfulness on CVD risk factors including physical activity, smoking, diet, obesity, blood pressure, and diabetes regulation. Plausible mechanisms include (1) improved attention control (e.g., ability to hold attention on experiences related to CVD risk, such as smoking, diet, physical activity, and medication adherence), (2) emotion regulation (e.g., improved stress response, self-efficacy, and skills to manage craving for cigarettes, palatable foods, and sedentary activities), and (3) self-awareness (e.g., self-referential processing and awareness of physical sensations due to CVD risk factors). Understanding mechanisms and theoretical framework should improve etiologic knowledge, providing customized mindfulness intervention targets that could enable greater mindfulness intervention efficacy.

Mindfulness and Cardiovascular Disease Risk: State of the Evidence, Plausible Mechanisms, and Theoretical Framework

PubMed Central

Schuman-Olivier, Zev; Britton, Willoughby B.; Fresco, David M.; Desbordes, Gaelle; Brewer, Judson A.; Fulwiler, Carl

2016-01-01

The purpose of this review is to provide (1) a synopsis on relations of mindfulness with cardiovascular disease (CVD) and major CVD risk factors, and (2) an initial consensus-based overview of mechanisms and theoretical framework by which mindfulness might influence CVD. Initial evidence, often of limited methodological quality, suggests possible impacts of mindfulness on CVD risk factors including physical activity, smoking, diet, obesity, blood pressure, and diabetes regulation. Plausible mechanisms include (1) improved attention control (e.g., ability to hold attention on experiences related to CVD risk, such as smoking, diet, physical activity, and medication adherence), (2) emotion regulation (e.g., improved stress response, self-efficacy, and skills to manage craving for cigarettes, palatable foods, and sedentary activities), and (3) self-awareness (e.g., self-referential processing and awareness of physical sensations due to CVD risk factors). Understanding mechanisms and theoretical framework should improve etiologic knowledge, providing customized mindfulness intervention targets that could enable greater mindfulness intervention efficacy. PMID:26482755

Translations on USSR Science and Technology, Physical Sciences and Technology, Number 45

DTIC Science & Technology

1978-08-14

hundred pages. [Question] In the public’s perception a cosmonaut seems to be, in terms of physical and mental fitness, something like a superman . How ...indicate how the original information was processed. Where no processing indicator is given, the information was summarized or extracted. Unfamiliar... how the original Information was processed. Where no processing indicator is given, the information was sipmarized or extracted, unfamiliar names

Intentional and automatic processing of numerical information in mathematical anxiety: testing the influence of emotional priming.

PubMed

Ashkenazi, Sarit

2018-02-05

Current theoretical approaches suggest that mathematical anxiety (MA) manifests itself as a weakness in quantity manipulations. This study is the first to examine automatic versus intentional processing of numerical information using the numerical Stroop paradigm in participants with high MA. To manipulate anxiety levels, we combined the numerical Stroop task with an affective priming paradigm. We took a group of college students with high MA and compared their performance to a group of participants with low MA. Under low anxiety conditions (neutral priming), participants with high MA showed relatively intact number processing abilities. However, under high anxiety conditions (mathematical priming), participants with high MA showed (1) higher processing of the non-numerical irrelevant information, which aligns with the theoretical view regarding deficits in selective attention in anxiety and (2) an abnormal numerical distance effect. These results demonstrate that abnormal, basic numerical processing in MA is context related.

The cellular transducer in bone: What is it?

PubMed

Taylor, David; Hazenberg, Jan; Lee, T Clive

2006-01-01

Bone is able to detect its strain environment and respond accordingly. In particular it is able to adapt to over-use and under-use by bone deposition or resorption. How can bone sense strain? Various physical mechanisms have been proposed for the so-called cellular transducer, but there is no conclusive proof for any one of them. This paper examines the theories and evidence, with particular reference to a new theory proposed by the authors, involving damage to cellular processes by microcracks. Experiments on bone samples ex-vivo showed that cracks cannot fracture osteocytes, but that cellular processes which span the crack can be broken. A theoretical model was developed for predicting the number of broken processes as a function of crack size and applied stress. This showed that signals emitted by fractured processes could be used to detect cracks which needed repairing and to provide information on the overall level of damage which could be used to initiate repair and adaptation responses.

Maximum entropy models of ecosystem functioning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bertram, Jason, E-mail: jason.bertram@anu.edu.au

2014-12-05

Using organism-level traits to deduce community-level relationships is a fundamental problem in theoretical ecology. This problem parallels the physical one of using particle properties to deduce macroscopic thermodynamic laws, which was successfully achieved with the development of statistical physics. Drawing on this parallel, theoretical ecologists from Lotka onwards have attempted to construct statistical mechanistic theories of ecosystem functioning. Jaynes’ broader interpretation of statistical mechanics, which hinges on the entropy maximisation algorithm (MaxEnt), is of central importance here because the classical foundations of statistical physics do not have clear ecological analogues (e.g. phase space, dynamical invariants). However, models based on themore » information theoretic interpretation of MaxEnt are difficult to interpret ecologically. Here I give a broad discussion of statistical mechanical models of ecosystem functioning and the application of MaxEnt in these models. Emphasising the sample frequency interpretation of MaxEnt, I show that MaxEnt can be used to construct models of ecosystem functioning which are statistical mechanical in the traditional sense using a savanna plant ecology model as an example.« less

Evaluating for impact: what type of data can assist a health promoting school approach?

PubMed

Joyce, Andrew; Dabrowski, Anna; Aston, Ruth; Carey, Gemma

2017-04-01

There is debate within the health promoting school (HPS) movement on whether schools should monitor health behaviour outcomes as part of an evaluation or rely more on process type measures, such as changes to school policies and the physical and social environment which yield information about (in)effective implementation. The debate is often framed around ideological considerations of the role of schools and there is little empirical work on how these indicators of effective implementation can influence change at a policy and practice level in real world settings. Information has potentially powerful effects in motivating a change process, but this will vary according to the type of information and the type of organizational culture into which it is presented. The current predominant model relies on process data, policy and environmental audit monitoring and benchmarking approaches, and there is little evidence of whether this engages school communities. Theoretical assertions on the importance of monitoring data to motivate change need to be empirically tested and, in doing so, we can learn which types of data influence adoption of HPS in which types of school and policy contexts. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Perspective on Models in Theoretical and Practical Traditions of Knowledge: The Example of Otto Engine Animations

ERIC Educational Resources Information Center

Haglund, Jesper; Stromdahl, Helge

2012-01-01

Nineteen informants (n = 19) were asked to study and comment two computer animations of the Otto combustion engine. One animation was non-interactive and realistic in the sense of depicting a physical engine. The other animation was more idealised, interactive and synchronised with a dynamic PV-graph. The informants represented practical and…

Doctor Julius Robert Mayer and Energy Processes in Living Systems

ERIC Educational Resources Information Center

Erlichson, Herman

2007-01-01

The overwhelming majority of important papers in physics are written by physicists. But the physician Julius Robert Mayer (1814-1878, see photo) did a valid theoretical calculation of the mechanical equivalent of heat just before Joule reported on his results from his well-known paddle-wheel experiments. Joule is well-known to physics people and…

Pathways to Children's Academic Performance and Prosocial Behaviour: Roles of Physical Health Status, Environmental, Family, and Child Factors

ERIC Educational Resources Information Center

King, Gillian; McDougall, Janette; DeWit, David; Hong, Sungjin; Miller, Linda; Offord, David; Meyer, Katherine; LaPorta, John

2005-01-01

The objective of this article is to examine the pathways by which children's physical health status, environmental, family, and child factors affect children's academic performance and prosocial behaviour, using a theoretically-based and empirically-based model of competence development. The model proposes that 3 types of relational processes,…

Understanding perceived determinants of nurses' eating and physical activity behaviour: a theory-informed qualitative interview study.

PubMed

Power, Brian T; Kiezebrink, Kirsty; Allan, Julia L; Campbell, Marion K

2017-01-01

Unhealthy eating and physical activity behaviours are common among nurses but little is known about determinants of eating and physical activity behaviour in this population. The present study used a theoretical framework which summarises the many possible determinants of different health behaviours (the Theoretical Domains Framework; TDF) to systematically explore the most salient determinants of unhealthy eating and physical activity behaviour in hospital-based nurses. Semi-structured qualitative interviews based on the TDF were conducted with nurses ( n  = 16) to explore factors that behavioural theories suggest may influence nurses' eating and physical activity behaviour. Important determinants of the target behaviours were identified using both inductive coding (of categories emerging from the data) and deductive coding (of categories derived from the TDF) of the qualitative data. Thirteen of the fourteen domains in the TDF were found to influence nurses' eating and physical activity behaviour. Within these domains, important barriers to engaging in healthy eating and physical activity behaviour were shift work, fatigue, stress, beliefs about negative consequences, the behaviours of family and friends and lack of planning. Important factors reported to enable engagement with healthy eating and physical activity behaviours were beliefs about benefits, the use of self-monitoring strategies, support from work colleagues, confidence, shift work, awareness of useful guidelines and strategies, good mood, future holidays and receiving compliments. This study used a theory-informed approach by applying the TDF to identify the key perceived determinants of nurses' eating and physical activity behaviour. The findings suggest that future efforts to change nurses' eating and physical activity behaviours should consider targeting a broad range of environmental, interpersonal and intrapersonal level factors, consistent with a socio-ecological perspective.

Acting to gain information

NASA Technical Reports Server (NTRS)

Rosenchein, Stanley J.; Burns, J. Brian; Chapman, David; Kaelbling, Leslie P.; Kahn, Philip; Nishihara, H. Keith; Turk, Matthew

1993-01-01

This report is concerned with agents that act to gain information. In previous work, we developed agent models combining qualitative modeling with real-time control. That work, however, focused primarily on actions that affect physical states of the environment. The current study extends that work by explicitly considering problems of active information-gathering and by exploring specialized aspects of information-gathering in computational perception, learning, and language. In our theoretical investigations, we analyzed agents into their perceptual and action components and identified these with elements of a state-machine model of control. The mathematical properties of each was developed in isolation and interactions were then studied. We considered the complexity dimension and the uncertainty dimension and related these to intelligent-agent design issues. We also explored active information gathering in visual processing. Working within the active vision paradigm, we developed a concept of 'minimal meaningful measurements' suitable for demand-driven vision. We then developed and tested an architecture for ongoing recognition and interpretation of visual information. In the area of information gathering through learning, we explored techniques for coping with combinatorial complexity. We also explored information gathering through explicit linguistic action by considering the nature of conversational rules, coordination, and situated communication behavior.

PREFACE: 1st International Workshop on Theoretical and Computational Physics: Condensed Matter, Soft Matter and Materials Physics & 38th National Conference on Theoretical Physics

NASA Astrophysics Data System (ADS)

2014-09-01

This volume contains selected papers presented at the 38th National Conference on Theoretical Physics (NCTP-38) and the 1st International Workshop on Theoretical and Computational Physics: Condensed Matter, Soft Matter and Materials Physics (IWTCP-1). Both the conference and the workshop were held from 29 July to 1 August 2013 in Pullman hotel, Da Nang, Vietnam. The IWTCP-1 was a new activity of the Vietnamese Theoretical Physics Society (VTPS) organized in association with the 38th National Conference on Theoretical Physics (NCTP-38), the most well-known annual scientific forum dedicated to the dissemination of the latest development in the field of theoretical physics within the country. The IWTCP-1 was also an External Activity of the Asia Pacific Center for Theoretical Physics (APCTP). The overriding goal of the IWTCP is to provide an international forum for scientists and engineers from academia to share ideas, problems and solution relating to the recent advances in theoretical physics as well as in computational physics. The main IWTCP motivation is to foster scientific exchanges between the Vietnamese theoretical and computational physics community and world-wide scientists as well as to promote high-standard level of research and education activities for young physicists in the country. About 110 participants coming from 10 countries participated in the conference and the workshop. 4 invited talks, 18 oral contributions and 46 posters were presented at the conference. In the workshop we had one keynote lecture and 9 invited talks presented by international experts in the fields of theoretical and computational physics, together with 14 oral and 33 poster contributions. The proceedings were edited by Nguyen Tri Lan, Trinh Xuan Hoang, and Nguyen Ai Viet. We would like to thank all invited speakers, participants and sponsors for making the conference and the workshop successful. Nguyen Ai Viet Chair of NCTP-38 and IWTCP-1

[L.A. Blumenfeld and study of photosynthesis by spectroscopy methods at Chair of Biophysics, Faculty of Physics, Moscow State University].

PubMed

Kukushkin, A K

2013-01-01

Nowadays spectroscopy methods are widely employed to study photosynthesis. For instance, fluorescence methods are often in use to study virtually all steps of photosynthesis process. Theoretical models of phenomena under study are of importance for interpretation of experimental data. A decisive role of L.A. Blumenfeld, the former head of the Chair of Biophysics, Faculty of Physics, Moscow State University, in the study of photosynthesis process is shown in this work.

Multi-scale Modeling of Chromosomal DNA in Living Cells

NASA Astrophysics Data System (ADS)

Spakowitz, Andrew

The organization and dynamics of chromosomal DNA play a pivotal role in a range of biological processes, including gene regulation, homologous recombination, replication, and segregation. Establishing a quantitative theoretical model of DNA organization and dynamics would be valuable in bridging the gap between the molecular-level packaging of DNA and genome-scale chromosomal processes. Our research group utilizes analytical theory and computational modeling to establish a predictive theoretical model of chromosomal organization and dynamics. In this talk, I will discuss our efforts to develop multi-scale polymer models of chromosomal DNA that are both sufficiently detailed to address specific protein-DNA interactions while capturing experimentally relevant time and length scales. I will demonstrate how these modeling efforts are capable of quantitatively capturing aspects of behavior of chromosomal DNA in both prokaryotic and eukaryotic cells. This talk will illustrate that capturing dynamical behavior of chromosomal DNA at various length scales necessitates a range of theoretical treatments that accommodate the critical physical contributions that are relevant to in vivo behavior at these disparate length and time scales. National Science Foundation, Physics of Living Systems Program (PHY-1305516).

Physically secured orthogonal frequency division multiplexing-passive optical network employing noise-based encryption and signal recovery process

NASA Astrophysics Data System (ADS)

Jin, Wei; Zhang, Chongfu; Yuan, Weicheng

2016-02-01

We propose a physically enhanced secure scheme for direct detection-orthogonal frequency division multiplexing-passive optical network (DD-OFDM-PON) and long reach coherent detection-orthogonal frequency division multiplexing-passive optical network (LRCO-OFDM-PON), by employing noise-based encryption and channel/phase estimation. The noise data generated by chaos mapping are used to substitute training sequences in preamble to realize channel estimation and frame synchronization, and also to be embedded on variable number of key-selected randomly spaced pilot subcarriers to implement phase estimation. Consequently, the information used for signal recovery is totally hidden as unpredictable noise information in OFDM frames to mask useful information and to prevent illegal users from correctly realizing OFDM demodulation, and thereby enhancing resistance to attackers. The levels of illegal-decryption complexity and implementation complexity are theoretically discussed. Through extensive simulations, the performances of the proposed channel/phase estimation and the security introduced by encrypted pilot carriers have been investigated in both DD-OFDM and LRCO-OFDM systems. In addition, in the proposed secure DD-OFDM/LRCO-OFDM PON models, both legal and illegal receiving scenarios have been considered. These results show that, by utilizing the proposed scheme, the resistance to attackers can be significantly enhanced in DD-OFDM-PON and LRCO-OFDM-PON systems without performance degradations.

Theoretical and experimental studies in ultraviolet solar physics

NASA Technical Reports Server (NTRS)

Parkinson, W. H.; Reeves, E. M.

1975-01-01

The processes and parameters in atomic and molecular physics that are relevant to solar physics are investigated. The areas covered include: (1) measurement of atomic and molecular parameters that contribute to discrete and continous sources of opacity and abundance determinations in the sun; (2) line broadening and scattering phenomena; and (3) development of an ion beam spectroscopic source which is used for the measurement of electron excitation cross sections of transition region and coronal ions.

Theoretical studies of spectroscopic problems of importance for atmospheric radiation measurements

NASA Technical Reports Server (NTRS)

Tipping, Richard H.

1994-01-01

Many of the instruments used to deduce the physical parameters of the Earth's atmosphere necessary for climate studies or for pollution monitoring (for instance, temperature versus pressure or number densities of trace molecules) rely on the existence of accurate spectroscopic data and an understanding of the physical processes responsible for the absorption or emission of radiation. During the summer, research was either continued or begun on three distinct problems: (1) an improved theoretical framework for the calculation of the far-wing absorption of allowed spectral lines; (2) a refinement of the calculation of the collision-induced fundamental spectrum of N2; and (3) an investigation of possible line-mixing effects in the fundamental spectrum of CH4. Progress in these three areas is summarized below. During the past few years, we have developed a theoretical framework for the calculation of the absorption of radiation by the far wings of spectral lines. Such absorption due to water vapor plays a crucial role in the greenhouse effect as well as limiting the retrieval of temperature profiles from satellite data. Several improvements in the theory have been made and the results are being prepared for publication. Last year we published results for the theoretical calculation of the absorption of radiation due to the dipoles induced during binary collisions of N2 molecules using independently measured molecular parameters; the results were in reasonable agreement with experimental data. However, recent measurements have revealed new fine structure that has been attributed to line-mixing effects. We do not think that this is correct, rather that the structure results from short-range anisotropic dipoles. We are in the process of including this refinement in our theoretical calculation in order to compare with the new experimental data. Subtle changes in the spectra of CH4 measured by researchers at Langley have also been attributed to line-mixing effects. By analyzing the same spectral lines we have attempted to verify or rule out possible line-mixing mechanisms. Due to the complexity and richness of the spectrum of this highly symmetric molecule, as well as the small magnitude of the effects, a detailed first-principle calculation of the mixing is a difficult problem. Before such a program is undertaken it is important to glean as much information as possible concerning the possible mechanisms by a systematic analysis of the existing data.

Efficient universal quantum channel simulation in IBM's cloud quantum computer

NASA Astrophysics Data System (ADS)

Wei, Shi-Jie; Xin, Tao; Long, Gui-Lu

2018-07-01

The study of quantum channels is an important field and promises a wide range of applications, because any physical process can be represented as a quantum channel that transforms an initial state into a final state. Inspired by the method of performing non-unitary operators by the linear combination of unitary operations, we proposed a quantum algorithm for the simulation of the universal single-qubit channel, described by a convex combination of "quasi-extreme" channels corresponding to four Kraus operators, and is scalable to arbitrary higher dimension. We demonstrated the whole algorithm experimentally using the universal IBM cloud-based quantum computer and studied the properties of different qubit quantum channels. We illustrated the quantum capacity of the general qubit quantum channels, which quantifies the amount of quantum information that can be protected. The behavior of quantum capacity in different channels revealed which types of noise processes can support information transmission, and which types are too destructive to protect information. There was a general agreement between the theoretical predictions and the experiments, which strongly supports our method. By realizing the arbitrary qubit channel, this work provides a universally- accepted way to explore various properties of quantum channels and novel prospect for quantum communication.

Reflections of the social environment in chimpanzee memory: applying rational analysis beyond humans.

PubMed

Stevens, Jeffrey R; Marewski, Julian N; Schooler, Lael J; Gilby, Ian C

2016-08-01

In cognitive science, the rational analysis framework allows modelling of how physical and social environments impose information-processing demands onto cognitive systems. In humans, for example, past social contact among individuals predicts their future contact with linear and power functions. These features of the human environment constrain the optimal way to remember information and probably shape how memory records are retained and retrieved. We offer a primer on how biologists can apply rational analysis to study animal behaviour. Using chimpanzees ( Pan troglodytes ) as a case study, we modelled 19 years of observational data on their social contact patterns. Much like humans, the frequency of past encounters in chimpanzees linearly predicted future encounters, and the recency of past encounters predicted future encounters with a power function. Consistent with the rational analyses carried out for human memory, these findings suggest that chimpanzee memory performance should reflect those environmental regularities. In re-analysing existing chimpanzee memory data, we found that chimpanzee memory patterns mirrored their social contact patterns. Our findings hint that human and chimpanzee memory systems may have evolved to solve similar information-processing problems. Overall, rational analysis offers novel theoretical and methodological avenues for the comparative study of cognition.

Reflections of the social environment in chimpanzee memory: applying rational analysis beyond humans

PubMed Central

Marewski, Julian N.; Schooler, Lael J.; Gilby, Ian C.

2016-01-01

In cognitive science, the rational analysis framework allows modelling of how physical and social environments impose information-processing demands onto cognitive systems. In humans, for example, past social contact among individuals predicts their future contact with linear and power functions. These features of the human environment constrain the optimal way to remember information and probably shape how memory records are retained and retrieved. We offer a primer on how biologists can apply rational analysis to study animal behaviour. Using chimpanzees (Pan troglodytes) as a case study, we modelled 19 years of observational data on their social contact patterns. Much like humans, the frequency of past encounters in chimpanzees linearly predicted future encounters, and the recency of past encounters predicted future encounters with a power function. Consistent with the rational analyses carried out for human memory, these findings suggest that chimpanzee memory performance should reflect those environmental regularities. In re-analysing existing chimpanzee memory data, we found that chimpanzee memory patterns mirrored their social contact patterns. Our findings hint that human and chimpanzee memory systems may have evolved to solve similar information-processing problems. Overall, rational analysis offers novel theoretical and methodological avenues for the comparative study of cognition. PMID:27853606

When a new technological product launching fails: A multi-method approach of facial recognition and E-WOM sentiment analysis.

PubMed

Hernández-Fernández, Dra Asunción; Mora, Elísabet; Vizcaíno Hernández, María Isabel

2018-04-17

The dual aim of this research is, firstly, to analyze the physiological and unconscious emotional response of consumers to a new technological product and, secondly, link this emotional response to consumer conscious verbal reports of positive and negative product perceptions. In order to do this, biometrics and self-reported measures of emotional response are combined. On the one hand, a neuromarketing experiment based on the facial recognition of emotions of 10 subjects, when physical attributes and economic information of a technological product are exposed, shows the prevalence of the ambivalent emotion of surprise. On the other hand, a nethnographic qualitative approach of sentiment analysis of 67-user online comments characterise the valence of this emotion as mainly negative in the case and context studied. Theoretical, practical and methodological contributions are anticipated from this paper. From a theoretical point of view this proposal contributes valuable information to the product design process, to an effective development of the marketing mix variables of price and promotion, and to a successful selection of the target market. From a practical point of view, the approach employed in the case study on the product Google Glass provides empirical evidence useful in the decision making process for this and other technological enterprises launching a new product. And from a methodological point of view, the usefulness of integrated neuromarketing-eWOM analysis could contribute to the proliferation of this tandem in marketing research. Copyright © 2018 Elsevier Inc. All rights reserved.

Theoretical studies of the physics of the solar atmosphere

NASA Technical Reports Server (NTRS)

Hollweg, Joseph V.

1992-01-01

Significant advances in our theoretical basis for understanding several physical processes related to dynamical phenomena on the sun were achieved. We have advanced a new model for spicules and fibrils. We have provided a simple physical view of resonance absorption of MHD surface waves; this allowed an approximate mathematical procedure for obtaining a wealth of new analytical results which we applied to coronal heating and p-mode absorption at magnetic regions. We provided the first comprehensive models for the heating and acceleration of the transition region, corona, and solar wind. We provided a new view of viscosity under coronal conditions. We provided new insights into Alfven wave propagation in the solar atmosphere. And recently we have begun work in a new direction: parametric instabilities of Alfven waves.

Physics of the inner heliosphere: Mechanisms, models and observational signatures

NASA Technical Reports Server (NTRS)

Withbroe, George L.

1987-01-01

Selected problems concerned with the important physical processes that occur in the corona and solar wind acceleration region, particularly time dependent phenomena were studied. Both the physics of the phenomena and the resultant effects on observational signatures, particularly spectroscopic signatures were also studied. Phenomena under study include: wave motions, particularly Alfven and fast mode waves; the formation of standing shocks in the inner heliosphere as a result of momentum and/or heat addition to the wind; and coronal transient phenomena where momentum and/or heat are deposited in the corona to produce transient plasma heating and/or mass ejection. The development of theoretical models for the inner heliosphere, the theoretical investigation of spectroscopic plasma diagnostics for this region, and the analysis of existing skylab and other relevant data are also included.

The Peoples Republic of China High-Frequency Gravitational Wave Research Program

NASA Astrophysics Data System (ADS)

Baker, Robert M. L.

2009-03-01

For the past decade the Peoples Republic of China has been increasingly active in the pursuit of High-Frequency Gravitational Wave (HFGW) research. Much of their progress has been during 2008. An epochal achievement was the publication of the theoretical analysis of the Li-Baker HFGW detector in the European Physical Journal C (Li, et al., 2008), "Perturbative Photon Fluxes Generated by High-Frequency Gravitational Waves and Their Physical Effects"). Many Chinese scientists and graduate students have participated in these HFGW studies and their contributions are briefly discussed. Some of the key scientists and their institutions are as follows: first from Chongqing University: Zhenyun Fang, Director of the Institute of Theoretical Physics, Xing gang Wu, The Institute of Theoretical Physics, Nan Yang, The Institute of Gravitational Physics; Jun Luo, Huazhong University of Science and Technology (HUST), Wuhan, China, the Head of Gravitational Laboratory, Yang Zhang, University of Science and Technology of China, Associate Dean of the College of Sciences, Biao Li, Institute of Electronic Engineering of China Academy of Engineering Physics (CAEP), Chief of Microwave Antenna Division, Chuan-Ming Zhou, Technology Committee of Institute of Electronic Engineering of the CAEP, Jie Zhou, Institute of Electronic Engineering of the CAEP, Chief of the Signal Processing Division; Weijia Wen, Department of Physics, The Hong Kong University of Science and Technology. This Chinese HFGW team includes two parts: (1) Theoretical study and (2) Experimental investigation. These two parts have closed relations, and many cross projects, including cooperation between the American GravWave and Chinese HFGW teams. Referring to financial support, The Institute of Electronic Engineering (i.e., Microwave Laboratory) has already (June 2008) provided support more than three million Yuan for the HFGW detection project and this activity is discussed.

Identity economics and the brain: uncovering the mechanisms of social conflict

PubMed Central

Huettel, Scott A.; Kranton, Rachel E.

2012-01-01

Social contexts can have dramatic effects on decisions. When individuals recognize each other as coming from the same social group, they can coordinate their actions towards a common goal. Conversely, information about group differences can lead to conflicts both economic and physical. Understanding how social information shapes decision processes is now a core goal both of behavioural economics and neuroeconomics. Here, we describe the foundations for research that combines the theoretical framework from identity economics with the experimental methods of neuroscience. Research at this intersection would fill important gaps in the literature not addressed by current approaches in either of these disciplines, nor within social neuroscience, psychology or other fields. We set forth a simple taxonomy of social contexts based on the information content they provide. And, we highlight the key questions that would be addressed by a new ‘identity neuroeconomics’. Such research could serve as an important and novel link between the social and natural sciences. PMID:22271784

Reform and practice for photoelectric specialty experimental teaching based on virtual simulation experiment platform

NASA Astrophysics Data System (ADS)

Ye, Yan; Lv, Qingsong; Wu, Maocheng; Xu, Yishen; Gu, Jihua

2017-08-01

In view of some problems about the traditional photoelectric specialty experimental teaching process, such as separation of theoretical teaching and practical teaching, immobilization of experimental teaching contents, low quality of experiments and no obvious effect, we explored and practiced a new experimental teaching model of "theoretical teaching, virtual simulation and physical experiment", which combined the characteristics of photoelectric information science and engineering major and the essential requirements of engineering innovation talents cultivation. The virtual simulation experiment platform has many advantages, such as high performance-to-price ratio, easy operation and open experimental process, which makes virtual simulation combine physical experiment, complete each other with virtual for practical. After the users log into the virtual simulation experimental platform, they will first study the contents of the experiment, clarify the purpose and requirements of the experiment, master the method of using the instrument and the relevant notes, and then use the experimental instruments provided by the platform to build the corresponding experimental system. Once the experimenter's optical path is set incorrectly or the instrument parameters are set incorrectly, the error or warning message will be automatically triggered, and the reference information will be given instructing the student to complete the correct experimental operation. The results of our practice in recent years show that the teaching reform of the photoelectric specialty experiments has not only brought great convenience to the experimental teaching management, broadened the students' thinking and vision, enhanced the students' experimental skills and comprehensive qualities, but also made the students participate in the experiment with their enthusiasm. During the construction of experiment programs, the students' engineering practical ability and independent innovation awareness has been improved greatly. In the next time, based on the development trend of optoelectronic discipline and our own major characteristics, we will further perfect and enrich the construction of virtual simulation experimental platform and continuously improve the quality of experimental teaching.

Maximizing potential impact of experimental research into cognitive processes in health psychology: A systematic approach to material development.

PubMed

Hughes, Alicia M; Gordon, Rola; Chalder, Trudie; Hirsch, Colette R; Moss-Morris, Rona

2016-11-01

There is an abundance of research into cognitive processing biases in clinical psychology including the potential for applying cognitive bias modification techniques to assess the causal role of biases in maintaining anxiety and depression. Within the health psychology field, there is burgeoning interest in applying these experimental methods to assess potential cognitive biases in relation to physical health conditions and health-related behaviours. Experimental research in these areas could inform theoretical development by enabling measurement of implicit cognitive processes that may underlie unhelpful illness beliefs and help drive health-related behaviours. However, to date, there has been no systematic approach to adapting existing experimental paradigms for use within physical health research. Many studies fail to report how materials were developed for the population of interest or have used untested materials developed ad hoc. The lack of protocol for developing stimuli specificity has contributed to large heterogeneity in methodologies and findings. In this article, we emphasize the need for standardized methods for stimuli development and replication in experimental work, particularly as it extends beyond its original anxiety and depression scope to other physical conditions. We briefly describe the paradigms commonly used to assess cognitive biases in attention and interpretation and then describe the steps involved in comprehensive/robust stimuli development for attention and interpretation paradigms using illustrative examples from two conditions: chronic fatigue syndrome and breast cancer. This article highlights the value of preforming rigorous stimuli development and provides tools to aid researchers engage in this process. We believe this work is worthwhile to establish a body of high-quality and replicable experimental research within the health psychology literature. Statement of contribution What is already known on this subject? Cognitive biases (e.g., tendencies to attend to negative information and/or interpret ambiguous information in negative ways) have a causal role in maintaining anxiety and depression. There is mixed evidence of cognitive biases in physical health conditions and chronic illness; one reason for this may be the heterogeneous stimuli used to assess attention and interpretation biases in these conditions. What does this study add? Steps for comprehensive/robust stimuli development for attention and interpretation paradigms are presented. Illustrative examples are provided from two conditions: chronic fatigue syndrome and breast cancer. We provide tools to help researchers develop condition-specific materials for experimental studies. © 2016 The British Psychological Society.

Physical methods for investigating structural colours in biological systems

PubMed Central

Vukusic, P.; Stavenga, D.G.

2009-01-01

Many biological systems are known to use structural colour effects to generate aspects of their appearance and visibility. The study of these phenomena has informed an eclectic group of fields ranging, for example, from evolutionary processes in behavioural biology to micro-optical devices in technologically engineered systems. However, biological photonic systems are invariably structurally and often compositionally more elaborate than most synthetically fabricated photonic systems. For this reason, an appropriate gamut of physical methods and investigative techniques must be applied correctly so that the systems' photonic behaviour may be appropriately understood. Here, we survey a broad range of the most commonly implemented, successfully used and recently innovated physical methods. We discuss the costs and benefits of various spectrometric methods and instruments, namely scatterometers, microspectrophotometers, fibre-optic-connected photodiode array spectrometers and integrating spheres. We then discuss the role of the materials' refractive index and several of the more commonly used theoretical approaches. Finally, we describe the recent developments in the research field of photonic crystals and the implications for the further study of structural coloration in animals. PMID:19158009

Trajectories of change in self-esteem in older adults: exercise intervention effects.

PubMed

Gothe, Neha P; Mullen, Sean P; Wójcicki, Thomas R; Mailey, Emily L; White, Siobhan M; Olson, Erin A; Szabo, Amanda N; Kramer, Arthur F; McAuley, Edward

2011-08-01

This 12-month, 2 arm, single blind randomized controlled exercise trial examined relationships among changes in multidimensional self-esteem as a function of intervention mode (i.e., walking vs. flexibility-toning-balance). Data were collected on three equidistant occasions (baseline, 6 and 12 months). One-hundred seventy-nine older adults (M(age) = 66.38) began the study and 145 completed assessments at all time points. Participants completed measures of physical and global self-esteem as well as demographic information. There were no significant group differences at baseline on these demographic indicators or esteem variables. Data were analyzed using linear and parallel process growth modeling procedures. Results supported the position that across both groups, domain-level (i.e., physical self-worth) was dependent upon sub-domain-level (i.e., perceived attractiveness, strength, and condition) esteem change. Furthermore, greater improvements were observed in the flexibility-toning-balance group, in terms of perceived strength and attractiveness esteem, compared to the walking group. Our findings support theoretically-based predictions and extend the literature showing unique psychological responses conditional on specific types of physical activities.

Trajectories of change in self-esteem in older adults: exercise intervention effects

PubMed Central

Gothe, Neha P.; Mullen, Sean P.; Wójcicki, Thomas R.; Mailey, Emily L.; White, Siobhan M.; Olson, Erin A.; Szabo, Amanda N.; Kramer, Arthur F.

2011-01-01

This 12-month, 2 arm, single blind randomized controlled exercise trial examined relationships among changes in multidimensional self-esteem as a function of intervention mode (i.e., walking vs. flexibility-toning-balance). Data were collected on three equidistant occasions (baseline, 6 and 12 months). One-hundred seventy-nine older adults (Mage = 66.38) began the study and 145 completed assessments at all time points. Participants completed measures of physical and global self-esteem as well as demographic information. There were no significant group differences at baseline on these demographic indicators or esteem variables. Data were analyzed using linear and parallel process growth modeling procedures. Results supported the position that across both groups, domain-level (i.e., physical self-worth) was dependent upon sub-domain-level (i.e., perceived attractiveness, strength, and condition) esteem change. Furthermore, greater improvements were observed in the flexibility-toning-balance group, in terms of perceived strength and attractiveness esteem, compared to the walking group. Our findings support theoretically-based predictions and extend the literature showing unique psychological responses conditional on specific types of physical activities. PMID:21222223

Characterizing Pedagogical Practices of University Physics Students in Informal Learning Environments

NASA Astrophysics Data System (ADS)

Hinko, Kathleen

2016-03-01

University educators (UEs) have a long history of teaching physics not only in formal classroom settings but also in informal outreach environments. The pedagogical practices of UEs in informal physics teaching have not been widely studied, and they may provide insight into formal practices and preparation. We investigate the interactions between UEs and children in an afterschool physics program facilitated by university physics students from the University of Colorado Boulder. In this program, physics undergraduates, graduate students and post-doctoral researchers work with K-8 children on hands-on physics activities on a weekly basis over the course of a semester. We use an Activity Theoretic framework as a tool to examine situational aspects of individuals' behavior in the complex structure of the afterschool program. Using this framework, we analyze video of UE-child interactions and identify three main pedagogical modalities that UEs display during activities: Instruction, Consultation and Participation modes. These modes are characterized by certain language, physical location, and objectives that establish differences in UE-child roles and division of labor. Based on this analysis, we discuss implications for promoting pedagogical strategies through purposeful curriculum development and university educator preparation.

Promoting Visualization Skills through Deconstruction Using Physical Models and a Visualization Activity Intervention

NASA Astrophysics Data System (ADS)

Schiltz, Holly Kristine

Visualization skills are important in learning chemistry, as these skills have been shown to correlate to high ability in problem solving. Students' understanding of visual information and their problem-solving processes may only ever be accessed indirectly: verbalization, gestures, drawings, etc. In this research, deconstruction of complex visual concepts was aligned with the promotion of students' verbalization of visualized ideas to teach students to solve complex visual tasks independently. All instructional tools and teaching methods were developed in accordance with the principles of the theoretical framework, the Modeling Theory of Learning: deconstruction of visual representations into model components, comparisons to reality, and recognition of students' their problemsolving strategies. Three physical model systems were designed to provide students with visual and tangible representations of chemical concepts. The Permanent Reflection Plane Demonstration provided visual indicators that students used to support or invalidate the presence of a reflection plane. The 3-D Coordinate Axis system provided an environment that allowed students to visualize and physically enact symmetry operations in a relevant molecular context. The Proper Rotation Axis system was designed to provide a physical and visual frame of reference to showcase multiple symmetry elements that students must identify in a molecular model. Focus groups of students taking Inorganic chemistry working with the physical model systems demonstrated difficulty documenting and verbalizing processes and descriptions of visual concepts. Frequently asked student questions were classified, but students also interacted with visual information through gestures and model manipulations. In an effort to characterize how much students used visualization during lecture or recitation, we developed observation rubrics to gather information about students' visualization artifacts and examined the effect instructors' modeled visualization artifacts had on students. No patterns emerged from the passive observation of visualization artifacts in lecture or recitation, but the need to elicit visual information from students was made clear. Deconstruction proved to be a valuable method for instruction and assessment of visual information. Three strategies for using deconstruction in teaching were distilled from the lessons and observations of the student focus groups: begin with observations of what is given in an image and what it's composed of, identify the relationships between components to find additional operations in different environments about the molecule, and deconstructing steps of challenging questions can reveal mistakes. An intervention was developed to teach students to use deconstruction and verbalization to analyze complex visualization tasks and employ the principles of the theoretical framework. The activities were scaffolded to introduce increasingly challenging concepts to students, but also support them as they learned visually demanding chemistry concepts. Several themes were observed in the analysis of the visualization activities. Students used deconstruction by documenting which parts of the images were useful for interpretation of the visual. Students identified valid patterns and rules within the images, which signified understanding of arrangement of information presented in the representation. Successful strategy communication was identified when students documented personal strategies that allowed them to complete the activity tasks. Finally, students demonstrated the ability to extend symmetry skills to advanced applications they had not previously seen. This work shows how the use of deconstruction and verbalization may have a great impact on how students master difficult topics and combined, they offer students a powerful strategy to approach visually demanding chemistry problems and to the instructor a unique insight to mentally constructed strategies.

Efficient numerical evaluation of Feynman integrals

NASA Astrophysics Data System (ADS)

Li, Zhao; Wang, Jian; Yan, Qi-Shu; Zhao, Xiaoran

2016-03-01

Feynman loop integrals are a key ingredient for the calculation of higher order radiation effects, and are responsible for reliable and accurate theoretical prediction. We improve the efficiency of numerical integration in sector decomposition by implementing a quasi-Monte Carlo method associated with the CUDA/GPU technique. For demonstration we present the results of several Feynman integrals up to two loops in both Euclidean and physical kinematic regions in comparison with those obtained from FIESTA3. It is shown that both planar and non-planar two-loop master integrals in the physical kinematic region can be evaluated in less than half a minute with accuracy, which makes the direct numerical approach viable for precise investigation of higher order effects in multi-loop processes, e.g. the next-to-leading order QCD effect in Higgs pair production via gluon fusion with a finite top quark mass. Supported by the Natural Science Foundation of China (11305179 11475180), Youth Innovation Promotion Association, CAS, IHEP Innovation (Y4545170Y2), State Key Lab for Electronics and Particle Detectors, Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Y4KF061CJ1), Cluster of Excellence Precision Physics, Fundamental Interactions and Structure of Matter (PRISMA-EXC 1098)

Relationship of Health Behavior Theories with Self-Efficacy among Insufficiently Active Hypertensive African-American Women

PubMed Central

Martin, Michelle Y.; Person, Sharina; Kratt, Polly; Prayor-Patterson, Heather; Kim, Young; Salas, Maribel; Pisu, Maria

2011-01-01

Objective While self-efficacy plays an important role in physical activity, relatively little research has examined this construct in minorities. This study identified theoretical correlates associated with self-efficacy amongst insufficiently active, hypertensive Black women. Methods Correlates of self-efficacy to: (1) overcoming barriers to physical activity; (2) making time for activity; and (3) “sticking with” physical activity were studied. Results Sixty-one women (M = 50.48 ± 4.2 years) participated. We accounted for 32% of the variance in confidence in overcoming barriers. Women confident in overcoming barriers reported less worry about physical activity. The TTM processes of change were also in the model: consciousness raising, environmental reevaluation, counter conditioning, and self liberation. We accounted for 16% of the variance in “making time” self-efficacy. An aversiveness barrier (e.g., physical activity is boring, physical activity is hard work) was the dominant variable in the model. Confidence to ‘stick with’ physical activity was associated with self-reevaluation (i.e., reflection on how personal values correspond to behavior). Social support and competing demands were not associated with self-efficacy. Conclusions Consistent with Social Cognitive Theory, results suggest that self-efficacy is behavior specific and each measure likely provides unique information. Practice Implications Interventions should be tailored to address specific self-efficacy types. PMID:18395395

Physics through the 1990s: Elementary-particle physics

NASA Astrophysics Data System (ADS)

The volume begins with a non-mathematical discussion of the motivation behind, and basic ideas of, elementary-particle physics theory and experiment. The progress over the past two decades with the quark model and unification of the electromagnetic and weak interactions is reviewed. Existing theoretical problems in the field, such as the origin of mass and the unification of the fundamental forces, are detailed, along with experimental programs to test the new theories. Accelerators, instrumentation, and detectors are described for both current and future facilities. Interactions with other areas of both theoretical and applied physics are presented. The sociology of the field is examined regarding the education of graduate students, the organization necessary in large-scale experiments, and the decision-making process involved in high-cost experiments. Finally, conclusions and recommendations for maintaining US excellence in theory and experiment are given. Appendices list both current and planned accelerators, and present statistical data on the US elementary-particle physics program. A glossary is included.

Physics through the 1990s: elementary-particle physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1986-01-01

The volume begins with a non-mathematical discussion of the motivation behind, and basic ideas of, elementary-particle physics theory and experiment. The progress over the past two decades with the quark model and unification of the electromagnetic and weak interactions is reviewed. Existing theoretical problems in the field, such as the origin of mass and the unification of the fundamental forces, are detailed, along with experimental programs to test the new theories. Accelerators, instrumentation, and detectors are described for both current and future facilities. Interactions with other areas of both theoretical and applied physics are presented. The sociology of the fieldmore » is examined regarding the education of graduate students, the organization necessary in large-scale experiments, and the decision-making process involved in high-cost experiments. Finally, conclusions and recommendations for maintaining US excellence in theory and experiment are given. Appendices list both current and planned accelerators, and present statistical data on the US elementary-particle physics program. A glossary is included.« less

Physics through the 1990s: Elementary-particle physics

NASA Technical Reports Server (NTRS)

1986-01-01

The volume begins with a non-mathematical discussion of the motivation behind, and basic ideas of, elementary-particle physics theory and experiment. The progress over the past two decades with the quark model and unification of the electromagnetic and weak interactions is reviewed. Existing theoretical problems in the field, such as the origin of mass and the unification of the fundamental forces, are detailed, along with experimental programs to test the new theories. Accelerators, instrumentation, and detectors are described for both current and future facilities. Interactions with other areas of both theoretical and applied physics are presented. The sociology of the field is examined regarding the education of graduate students, the organization necessary in large-scale experiments, and the decision-making process involved in high-cost experiments. Finally, conclusions and recommendations for maintaining US excellence in theory and experiment are given. Appendices list both current and planned accelerators, and present statistical data on the US elementary-particle physics program. A glossary is included.

Studying Relational Spaces in Secondary School: Applying a Spatial Framework for the Study of Borderlands and Relational Work in School Improvement Processes

ERIC Educational Resources Information Center

Frelin, Anneli; Grannäs, Jan

2014-01-01

This article introduces a theoretical framework for studying school improvement processes such as making school environments safer. Using concepts from spatial theory, in which distinctions between mental, social and physical space are applied makes for a multidimensional analysis of processes of change. In a multilevel case study, these were…

Developing a targeted, theory-informed implementation intervention using two theoretical frameworks to address health professional and organisational factors: a case study to improve the management of mild traumatic brain injury in the emergency department.

PubMed

Tavender, Emma J; Bosch, Marije; Gruen, Russell L; Green, Sally E; Michie, Susan; Brennan, Sue E; Francis, Jill J; Ponsford, Jennie L; Knott, Jonathan C; Meares, Sue; Smyth, Tracy; O'Connor, Denise A

2015-05-25

Despite the availability of evidence-based guidelines for the management of mild traumatic brain injury in the emergency department (ED), variations in practice exist. Interventions designed to implement recommended behaviours can reduce this variation. Using theory to inform intervention development is advocated; however, there is no consensus on how to select or apply theory. Integrative theoretical frameworks, based on syntheses of theories and theoretical constructs relevant to implementation, have the potential to assist in the intervention development process. This paper describes the process of applying two theoretical frameworks to investigate the factors influencing recommended behaviours and the choice of behaviour change techniques and modes of delivery for an implementation intervention. A stepped approach was followed: (i) identification of locally applicable and actionable evidence-based recommendations as targets for change, (ii) selection and use of two theoretical frameworks for identifying barriers to and enablers of change (Theoretical Domains Framework and Model of Diffusion of Innovations in Service Organisations) and (iii) identification and operationalisation of intervention components (behaviour change techniques and modes of delivery) to address the barriers and enhance the enablers, informed by theory, evidence and feasibility/acceptability considerations. We illustrate this process in relation to one recommendation, prospective assessment of post-traumatic amnesia (PTA) by ED staff using a validated tool. Four recommendations for managing mild traumatic brain injury were targeted with the intervention. The intervention targeting the PTA recommendation consisted of 14 behaviour change techniques and addressed 6 theoretical domains and 5 organisational domains. The mode of delivery was informed by six Cochrane reviews. It was delivered via five intervention components : (i) local stakeholder meetings, (ii) identification of local opinion leader teams, (iii) a train-the-trainer workshop for appointed local opinion leaders, (iv) local training workshops for delivery by trained local opinion leaders and (v) provision of tools and materials to prompt recommended behaviours. Two theoretical frameworks were used in a complementary manner to inform intervention development in managing mild traumatic brain injury in the ED. The effectiveness and cost-effectiveness of the developed intervention is being evaluated in a cluster randomised trial, part of the Neurotrauma Evidence Translation (NET) program.

[On-line processing mechanisms in text comprehension: a theoretical review on constructing situation models].

PubMed

Iseki, Ryuta

2004-12-01

This article reviewed research on construction of situation models during reading. To position variety of research in overall process appropriately, an unitary framework was devised in terms of three theories for on-line processing: resonance process, event-indexing model, and constructionist theory. Resonance process was treated as a basic activation mechanism in the framework. Event-indexing model was regarded as a screening system which selected and encoded activated information in situation models along with situational dimensions. Constructionist theory was considered to have a supervisory role based on coherence and explanation. From a view of the unitary framework, some problems concerning each theory were examined and possible interpretations were given. Finally, it was pointed out that there were little theoretical arguments on associative processing at global level and encoding text- and inference-information into long-term memory.

A Theoretical Mechanism of Szilard Engine Function in Nucleic Acids and the Implications for Quantum Coherence in Biological Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matthew Mihelic, F.

2010-12-22

Nucleic acids theoretically possess a Szilard engine function that can convert the energy associated with the Shannon entropy of molecules for which they have coded recognition, into the useful work of geometric reconfiguration of the nucleic acid molecule. This function is logically reversible because its mechanism is literally and physically constructed out of the information necessary to reduce the Shannon entropy of such molecules, which means that this information exists on both sides of the theoretical engine, and because information is retained in the geometric degrees of freedom of the nucleic acid molecule, a quantum gate is formed through whichmore » multi-state nucleic acid qubits can interact. Entangled biophotons emitted as a consequence of symmetry breaking nucleic acid Szilard engine (NASE) function can be used to coordinate relative positioning of different nucleic acid locations, both within and between cells, thus providing the potential for quantum coherence of an entire biological system. Theoretical implications of understanding biological systems as such 'quantum adaptive systems' include the potential for multi-agent based quantum computing, and a better understanding of systemic pathologies such as cancer, as being related to a loss of systemic quantum coherence.« less

A Theoretical Mechanism of Szilard Engine Function in Nucleic Acids and the Implications for Quantum Coherence in Biological Systems

NASA Astrophysics Data System (ADS)

Matthew Mihelic, F.

2010-12-01

Nucleic acids theoretically possess a Szilard engine function that can convert the energy associated with the Shannon entropy of molecules for which they have coded recognition, into the useful work of geometric reconfiguration of the nucleic acid molecule. This function is logically reversible because its mechanism is literally and physically constructed out of the information necessary to reduce the Shannon entropy of such molecules, which means that this information exists on both sides of the theoretical engine, and because information is retained in the geometric degrees of freedom of the nucleic acid molecule, a quantum gate is formed through which multi-state nucleic acid qubits can interact. Entangled biophotons emitted as a consequence of symmetry breaking nucleic acid Szilard engine (NASE) function can be used to coordinate relative positioning of different nucleic acid locations, both within and between cells, thus providing the potential for quantum coherence of an entire biological system. Theoretical implications of understanding biological systems as such "quantum adaptive systems" include the potential for multi-agent based quantum computing, and a better understanding of systemic pathologies such as cancer, as being related to a loss of systemic quantum coherence.

Teaching at the edge of knowledge: Non-equilibrium statistical physics

NASA Astrophysics Data System (ADS)

Schmittmann, Beate

2007-03-01

As physicists become increasingly interested in biological problems, we frequently find ourselves confronted with complex open systems, involving many interacting constituents and characterized by non-vanishing fluxes of mass or energy. Faced with the task of predicting macroscopic behaviors from microscopic information for these non-equilibrium systems, the familiar Gibbs-Boltzmann framework fails. The development of a comprehensive theoretical characterization of non-equilibrium behavior is one of the key challenges of modern condensed matter physics. In its absence, several approaches have been developed, from master equations to thermostatted molecular dynamics, which provide key insights into the rich and often surprising phenomenology of systems far from equilibrium. In my talk, I will address some of these methods, selecting those that are most relevant for a broad range of interdisciplinary problems from biology to traffic, finance, and sociology. The ``portability'' of these methods makes them valuable for graduate students from a variety of disciplines. To illustrate how different methods can complement each other when probing a problem from, e.g., the life sciences, I will discuss some recent attempts at modeling translation, i.e., the process by which the genetic information encoded on an mRNA is translated into the corresponding protein.

Generalized Bell states map physical systems’ quantum evolution into a grammar for quantum information processing

NASA Astrophysics Data System (ADS)

Delgado, Francisco

2017-12-01

Quantum information processing should be generated through control of quantum evolution for physical systems being used as resources, such as superconducting circuits, spinspin couplings in ions and artificial anyons in electronic gases. They have a quantum dynamics which should be translated into more natural languages for quantum information processing. On this terrain, this language should let to establish manipulation operations on the associated quantum information states as classical information processing does. This work shows how a kind of processing operations can be settled and implemented for quantum states design and quantum processing for systems fulfilling a SU(2) reduction in their dynamics.

Quantum computers: Definition and implementations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perez-Delgado, Carlos A.; Kok, Pieter

The DiVincenzo criteria for implementing a quantum computer have been seminal in focusing both experimental and theoretical research in quantum-information processing. These criteria were formulated specifically for the circuit model of quantum computing. However, several new models for quantum computing (paradigms) have been proposed that do not seem to fit the criteria well. Therefore, the question is what are the general criteria for implementing quantum computers. To this end, a formal operational definition of a quantum computer is introduced. It is then shown that, according to this definition, a device is a quantum computer if it obeys the following criteria:more » Any quantum computer must consist of a quantum memory, with an additional structure that (1) facilitates a controlled quantum evolution of the quantum memory; (2) includes a method for information theoretic cooling of the memory; and (3) provides a readout mechanism for subsets of the quantum memory. The criteria are met when the device is scalable and operates fault tolerantly. We discuss various existing quantum computing paradigms and how they fit within this framework. Finally, we present a decision tree for selecting an avenue toward building a quantum computer. This is intended to help experimentalists determine the most natural paradigm given a particular physical implementation.« less

[The Process of Healing Child Physical Abuse: Sprouting and Twining].

PubMed

Chang, Hsin-Yi; Feng, Jui-Ying; Tseng, Ren-Mei

2018-06-01

Child physical abuse impacts the physical and psychological health of survivors. Healing child abuse is an essential process that helps survivors reorganize the meaning of the trauma and pursue a normal life. Considering the trauma of child physical abuse within the social context allows the experiences of individual survivors to be reflected in their process of healing. To explore the social interaction and construction process of healing experienced by survivors of child physical abuse. A qualitative research design using grounded theory was applied. Purposive and theoretical sampling was used to recruit survivors of childhood physical abuse who had experienced healing. Semi-structured, in-depth interviews were used and data were analyzed using open, axial, and selective coding. The process of healing child physical abuse in this study was a process of sprouting and twining. Three core categories emerged: thriving, relationships, and ethics. The healing process was analogous to a seed growing in poor soil, sprouting out from the ground, and striving to live by seeking support. The survivors constantly established interactive relationships with their selves and with others and struggled to keep family bonds grounded and growing within the frame of ethics. The healing process of sprouting and twining for child physical abuse survivors in Taiwan integrates thriving, relationships, and ethics. Professionals working with child-physical-abuse survivors must recognize conflicts in ethics. Strategies should be developed to assist survivors to cope with the impact of childhood trauma in order to facilitate the healing process.

Theoretical model of dynamic spin polarization of nuclei coupled to paramagnetic point defects in diamond and silicon carbide

NASA Astrophysics Data System (ADS)

Ivády, Viktor; Szász, Krisztián; Falk, Abram L.; Klimov, Paul V.; Christle, David J.; Janzén, Erik; Abrikosov, Igor A.; Awschalom, David D.; Gali, Adam

2015-09-01

Dynamic nuclear spin polarization (DNP) mediated by paramagnetic point defects in semiconductors is a key resource for both initializing nuclear quantum memories and producing nuclear hyperpolarization. DNP is therefore an important process in the field of quantum-information processing, sensitivity-enhanced nuclear magnetic resonance, and nuclear-spin-based spintronics. DNP based on optical pumping of point defects has been demonstrated by using the electron spin of nitrogen-vacancy (NV) center in diamond, and more recently, by using divacancy and related defect spins in hexagonal silicon carbide (SiC). Here, we describe a general model for these optical DNP processes that allows the effects of many microscopic processes to be integrated. Applying this theory, we gain a deeper insight into dynamic nuclear spin polarization and the physics of diamond and SiC defects. Our results are in good agreement with experimental observations and provide a detailed and unified understanding. In particular, our findings show that the defect electron spin coherence times and excited state lifetimes are crucial factors in the entire DNP process.

Duality Quantum Simulation of the Yang-Baxter Equation

NASA Astrophysics Data System (ADS)

Zheng, Chao; Wei, Shijie

2018-04-01

The Yang-Baxter equation has become a significant theoretical tool in a variety of areas of physics. It is desirable to investigate the quantum simulation of the Yang-Baxter equation itself, exploring the connections between quantum integrability and quantum information processing, in which the unity of both the Yang-Baxter equation system and its quantum entanglement should be kept as a whole. In this work, we propose a duality quantum simulation algorithm of the Yang-Baxter equation, which contains the Yang-Baxter system and an ancillary qubit. Contrasting to conventional methods in which the two hand sides of the equation are simulated separately, they are simulated simultaneously in this proposal. Consequently, it opens up a way to further investigate entanglements in a Yang-Baxter equation.

Entanglement concentration and purification of two-mode squeezed microwave photons in circuit QED

NASA Astrophysics Data System (ADS)

Zhang, Hao; Alsaedi, Ahmed; Hayat, Tasawar; Deng, Fu-Guo

2018-04-01

We present a theoretical proposal for a physical implementation of entanglement concentration and purification protocols for two-mode squeezed microwave photons in circuit quantum electrodynamics (QED). First, we give the description of the cross-Kerr effect induced between two resonators in circuit QED. Then we use the cross-Kerr media to design the effective quantum nondemolition (QND) measurement on microwave-photon number. By using the QND measurement, the parties in quantum communication can accomplish the entanglement concentration and purification of nonlocal two-mode squeezed microwave photons. We discuss the feasibility of our schemes by giving the detailed parameters which can be realized with current experimental technology. Our work can improve some practical applications in continuous-variable microwave-based quantum information processing.

Duality Quantum Simulation of the Yang-Baxter Equation

NASA Astrophysics Data System (ADS)

Zheng, Chao; Wei, Shijie

2018-07-01

The Yang-Baxter equation has become a significant theoretical tool in a variety of areas of physics. It is desirable to investigate the quantum simulation of the Yang-Baxter equation itself, exploring the connections between quantum integrability and quantum information processing, in which the unity of both the Yang-Baxter equation system and its quantum entanglement should be kept as a whole. In this work, we propose a duality quantum simulation algorithm of the Yang-Baxter equation, which contains the Yang-Baxter system and an ancillary qubit. Contrasting to conventional methods in which the two hand sides of the equation are simulated separately, they are simulated simultaneously in this proposal. Consequently, it opens up a way to further investigate entanglements in a Yang-Baxter equation.

Fractional-order gradient descent learning of BP neural networks with Caputo derivative.

PubMed

Wang, Jian; Wen, Yanqing; Gou, Yida; Ye, Zhenyun; Chen, Hua

2017-05-01

Fractional calculus has been found to be a promising area of research for information processing and modeling of some physical systems. In this paper, we propose a fractional gradient descent method for the backpropagation (BP) training of neural networks. In particular, the Caputo derivative is employed to evaluate the fractional-order gradient of the error defined as the traditional quadratic energy function. The monotonicity and weak (strong) convergence of the proposed approach are proved in detail. Two simulations have been implemented to illustrate the performance of presented fractional-order BP algorithm on three small datasets and one large dataset. The numerical simulations effectively verify the theoretical observations of this paper as well. Copyright © 2017 Elsevier Ltd. All rights reserved.

PREFACE: 14th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2011)

NASA Astrophysics Data System (ADS)

Teodorescu, Liliana; Britton, David; Glover, Nigel; Heinrich, Gudrun; Lauret, Jérôme; Naumann, Axel; Speer, Thomas; Teixeira-Dias, Pedro

2012-06-01

ACAT2011 This volume of Journal of Physics: Conference Series is dedicated to scientific contributions presented at the 14th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2011) which took place on 5-7 September 2011 at Brunel University, UK. The workshop series, which began in 1990 in Lyon, France, brings together computer science researchers and practitioners, and researchers from particle physics and related fields in order to explore and confront the boundaries of computing and of automatic data analysis and theoretical calculation techniques. It is a forum for the exchange of ideas among the fields, exploring and promoting cutting-edge computing, data analysis and theoretical calculation techniques in fundamental physics research. This year's edition of the workshop brought together over 100 participants from all over the world. 14 invited speakers presented key topics on computing ecosystems, cloud computing, multivariate data analysis, symbolic and automatic theoretical calculations as well as computing and data analysis challenges in astrophysics, bioinformatics and musicology. Over 80 other talks and posters presented state-of-the art developments in the areas of the workshop's three tracks: Computing Technologies, Data Analysis Algorithms and Tools, and Computational Techniques in Theoretical Physics. Panel and round table discussions on data management and multivariate data analysis uncovered new ideas and collaboration opportunities in the respective areas. This edition of ACAT was generously sponsored by the Science and Technology Facility Council (STFC), the Institute for Particle Physics Phenomenology (IPPP) at Durham University, Brookhaven National Laboratory in the USA and Dell. We would like to thank all the participants of the workshop for the high level of their scientific contributions and for the enthusiastic participation in all its activities which were, ultimately, the key factors in the success of the workshop. Further information on ACAT 2011 can be found at http://acat2011.cern.ch Dr Liliana Teodorescu Brunel University ACATgroup The PDF also contains details of the workshop's committees and sponsors.

Implementation of the SMART MOVE intervention in primary care: a qualitative study using normalisation process theory.

PubMed

Glynn, Liam G; Glynn, Fergus; Casey, Monica; Wilkinson, Louise Gaffney; Hayes, Patrick S; Heaney, David; Murphy, Andrew W M

2018-05-02

Problematic translational gaps continue to exist between demonstrating the positive impact of healthcare interventions in research settings and their implementation into routine daily practice. The aim of this qualitative evaluation of the SMART MOVE trial was to conduct a theoretically informed analysis, using normalisation process theory, of the potential barriers and levers to the implementation of a mhealth intervention to promote physical activity in primary care. The study took place in the West of Ireland with recruitment in the community from the Clare Primary Care Network. SMART MOVE trial participants and the staff from four primary care centres were invited to take part and all agreed to do so. A qualitative methodology with a combination of focus groups (general practitioners, practice nurses and non-clinical staff from four separate primary care centres, n = 14) and individual semi-structured interviews (intervention and control SMART MOVE trial participants, n = 4) with purposeful sampling utilising the principles of Framework Analysis was utilised. The Normalisation Process Theory was used to develop the topic guide for the interviews and also informed the data analysis process. Four themes emerged from the analysis: personal and professional exercise strategies; roles and responsibilities to support active engagement; utilisation challenges; and evaluation, adoption and adherence. It was evident that introducing a new healthcare intervention demands a comprehensive evaluation of the intervention itself and also the environment in which it is to operate. Despite certain obstacles, the opportunity exists for the successful implementation of a novel healthcare intervention that addresses a hitherto unresolved healthcare need, provided that the intervention has strong usability attributes for both disseminators and target users and coheres strongly with the core objectives and culture of the health care environment in which it is to operate. We carried out a theoretical analysis of stakeholder informed barriers and levers to the implementation of a novel exercise promotion tool in the Irish primary care setting. We believe that this process amplifies the implementation potential of such an intervention in primary care. The SMART MOVE trial is registered at Current Controlled Trials (ISRCTN99944116; Date of registration: 1st August 2012).

Experimental Control of Simple Pendulum Model

ERIC Educational Resources Information Center

Medina, C.

2004-01-01

This paper conveys information about a Physics laboratory experiment for students with some theoretical knowledge about oscillatory motion. Students construct a simple pendulum that behaves as an ideal one, and analyze model assumption incidence on its period. The following aspects are quantitatively analyzed: vanishing friction, small amplitude,…

Promoting Sportsmanship in Youth Sports: Perspectives from Sport Psychology

ERIC Educational Resources Information Center

Goldstein, Jay D.; Iso-Ahola, Seppo E.

2006-01-01

This article introduces the physical education, recreation, and health practitioner to the relevant practical and theoretical information pertaining to sportsmanship in youth sports. It discusses four key areas related to sportsmanship: (1) constructs, (2) underlying theories, (3) empirical evidence, and (4) application and education. It also…

Theoretical Foundation for Weld Modeling

NASA Technical Reports Server (NTRS)

Traugott, S.

1986-01-01

Differential equations describe physics of tungsten/inert-gas and plasma-arc welding in aluminum. Report collects and describes necessary theoretical foundation upon which numerical welding model is constructed for tungsten/inert gas or plasma-arc welding in aluminum without keyhole. Governing partial differential equations for flow of heat, metal, and current given, together with boundary conditions relevant to welding process. Numerical estimates for relative importance of various phenomena and required properties of 2219 aluminum included

The physics of proton therapy.

PubMed

Newhauser, Wayne D; Zhang, Rui

2015-04-21

The physics of proton therapy has advanced considerably since it was proposed in 1946. Today analytical equations and numerical simulation methods are available to predict and characterize many aspects of proton therapy. This article reviews the basic aspects of the physics of proton therapy, including proton interaction mechanisms, proton transport calculations, the determination of dose from therapeutic and stray radiations, and shielding design. The article discusses underlying processes as well as selected practical experimental and theoretical methods. We conclude by briefly speculating on possible future areas of research of relevance to the physics of proton therapy.

The physics of proton therapy

PubMed Central

Newhauser, Wayne D; Zhang, Rui

2015-01-01

The physics of proton therapy has advanced considerably since it was proposed in 1946. Today analytical equations and numerical simulation methods are available to predict and characterize many aspects of proton therapy. This article reviews the basic aspects of the physics of proton therapy, including proton interaction mechanisms, proton transport calculations, the determination of dose from therapeutic and stray radiations, and shielding design. The article discusses underlying processes as well as selected practical experimental and theoretical methods. We conclude by briefly speculating on possible future areas of research of relevance to the physics of proton therapy. PMID:25803097

Large electroweak penguin contribution in B{yields}K{pi} and {pi}{pi} decay modes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mishima, Satoshi; Yoshikawa, Tadashi

2004-11-01

We discuss a possibility of large electroweak penguin contribution in B{yields}K{pi} and {pi}{pi} from recent experimental data. The experimental data may be suggesting that there are some discrepancies between the data and theoretical estimation in the branching ratios of them. In B{yields}K{pi} decays, to explain it, a large electroweak penguin contribution and large strong phase differences seem to be needed. The contributions should appear also in B{yields}{pi}{pi}. We show, as an example, a solution to solve the discrepancies in both B{yields}K{pi} and B{yields}{pi}{pi}. However the magnitude of the parameters and the strong phase estimated from experimental data are quite largemore » compared with the theoretical estimations. It may be suggesting some new physics effects are included in these processes. We will have to discuss about the dependence of the new physics. To explain both modes at once, we may need large electroweak penguin contribution with new weak phases and some SU(3) breaking effects by new physics in both QCD and electroweak penguin-type processes.« less

Korean immigrant women's physical activity experience: a situation-specific theory.

PubMed

Im, Eun-Ok; Chang, Sun Ju; Nguyen, Giang; Stringer, Lynn; Chee, Wonshik; Chee, Eunice

2015-01-01

To develop successful physical activity promotion programs for midlife immigrant women, especially for Korean immigrant midlife women, concrete theoretical bases are needed. However, virtually no theoretical frameworks and/or theories exist that can explain the influences of immigration transition on the physical activity experience of midlife immigrant women in general or Korean immigrant midlife women in specific. The purpose of this article is to present a situation-specific theory on physical activity experience of Korean immigrant midlife women (SPAKIM) with its development process. An integrative approach was used to develop the theory based on the midlife women's attitudes toward physical activity (MAPA) theory, the transitions theory, a review of the relevant literature, and two studies on midlife women's attitudes toward physical activity. The proposed theory includes nature of transitions, nonmodifiable and modifiable transition conditions, contexts of daily life, patterns of response, and nursing therapeutics as major concepts, and each major concept includes several related subconcepts. Because several concepts of the theory were developed mainly based on the literature review, the major concepts and related subconcepts need to be further developed and evaluated in future studies.

Book Review: A history of the ideas of theoretical physics: Essays on the 19th and 20th century physics (Vol. 213 of Boston Studies in the Philosophy of Science). Salvo d'Agostino; Kluwer Academic Publishers, Dordrecht, Boston, London, 2000, 381pp., 173.00 US, ISBN 0-7923-6094-X

NASA Astrophysics Data System (ADS)

Nordmann, Alfred

2003-12-01

The title of Salvo d'Agostino's book suggests that it may contain a collection of various and sundry ideas from the history of theoretical physics. However, d'Agostino pursues something far more specific and compelling, yet also far more controversial: a history of the idea of theoretical physics. When, how, and why did physics become theoretical physics, and what did this shift mean? While some would argue that physics became theoretical at a time of stasis and sterility, perhaps decadence or crisis, d'Agostino considers the epistemological turn of physics liberating, productive, even empowering.

Quark soup al dente: applied superstring theory

NASA Astrophysics Data System (ADS)

Myers, R. C.; Vázquez, S. E.

2008-06-01

In recent years, experiments have discovered an exotic new state of matter known as the strongly coupled quark gluon plasma (sQGP). At present, it seems that standard theoretical tools, such as perturbation theory and lattice gauge theory, are poorly suited to understand this new phase. However, recent progress in superstring theory has provided us with a theoretical laboratory for studying very similar systems of strongly interacting hot non-Abelian plasmas. This surprising new perspective extracts the fluid properties of the sQGP from physical processes in a black hole spacetime. Hence we may find the answers to difficult particle physics questions about the sQGP from straightforward calculations in classical general relativity.

Characterizing pedagogical practices of university physics students in informal learning environments

NASA Astrophysics Data System (ADS)

Hinko, Kathleen A.; Madigan, Peter; Miller, Eric; Finkelstein, Noah D.

2016-06-01

[This paper is part of the Focused Collection on Preparing and Supporting University Physics Educators.] University educators (UEs) have a long history of teaching physics not only in formal classroom settings but also in informal outreach environments. The pedagogical practices of UEs in informal physics teaching have not been widely studied, and they may provide insight into formal practices and preparation. We investigate the interactions between UEs and children in an afterschool physics program facilitated by university physics students from the University of Colorado Boulder. In this program, physics undergraduates, graduate students, and postdoctoral researchers work with K-8 children on hands-on physics activities on a weekly basis over the course of a semester. We use an activity theoretic framework as a tool to examine situational aspects of individuals' behavior in the complex structure of the afterschool program. Using this framework, we analyze video of UE-child interactions and identify three main pedagogical modalities that UEs display during activities: instruction, consultation, and participation modes. These modes are characterized by certain language, physical location, and objectives that establish differences in UE-child roles and division of labor. Based on this analysis, we discuss implications for promoting pedagogical strategies through purposeful curriculum development and university educator preparation.

Electron collisions—experiment, theory, and applications

NASA Astrophysics Data System (ADS)

Bartschat, Klaus

2018-07-01

Electron collisions with atoms, ions, and molecules have represented an important area of ‘applied quantum mechanics’ for more than a century. This Topical Review is the write-up of the Allis Prize Lecture given by the author at the 2016 meeting of the Division of Atomic, Molecular, and Optical Physics of the American Physical Society and the 2017 Gaseous Electronics Conference. In light of the enormous size of the field, the examples presented were selected in order to tell the story of how experimental and theoretical/numerical methods have developed over time, how fruitful collaborations between data producers (experimentalists and theorists) and data users have led to significant progress, and how the results of these studies, which were often designed for fundamental research in order to push both experiment and theory to new frontiers, continue to be highly sought after for modeling applications in a variety of fields. The impact of electron collision studies on other fields, such as photoinduced processes and quantum information, is also discussed.

Enhancing the Quality of Financial Advice with Web 2.0 - An Approach Considering Social Capital in the Private Asset Allocation

NASA Astrophysics Data System (ADS)

Kundisch, Dennis; Zorzi, Robin

Although theoretically necessary, social capital is not considered within the process of asset allocation for private investors. Both the lack of appropriate practical valuation concepts and the effort of providing and processing the required information as input for a valuation were obstacles to include social capital in this process. However, first theoretical financial models for the evaluation of social capital recently have become available. Moreover, the fast growth of business community websites and the technological progress in Web 2.0 tools that allow and acquire the active involvement of users, facilitate the provision and processing of valuation relevant information. In this paper we focus on the second aspect and propose a social software-based concept that allows for an integration of social capital in the asset allocation process.

Proton-hydrogen collisions for Rydberg n,l-changing transitions in the early Universe

NASA Astrophysics Data System (ADS)

Vrinceanu, Daniel

2013-05-01

Cosmic Microwave Background (CMB) is a vestige radiation generated during the Recombination era, some 390,000 years after the Big Bang, when the Universe had become transparent for the first time. Initial observations of CMB made by the Wilkinson Microwave Anisotropy Probe (WMAP) led to determining the age of the Universe. The mechanisms that drove the recombination have been discovered by using modeling of the primordial plasma and seeking agreement with the observations. The new Plank Surveyor Instrument launched in 2009 is expected to produce data about the recombination era of an unprecedented accuracy, that require including better information regarding the basic atomic physics processes into the present models. In this talk, I will review the results for various Rydberg atom - charge particle collisions and establish their relative importance during the stages of recombination era, with respect to each other and to radiative processes. Energy changing and angular momentum changing collisions with electrons and ions are considered. This work has been supported by NSF through grants to the Institute for Theoretical Atomic and Molecular Physics at Harvard Smithsonian Center for Astrophysics and to the Center for Research on Complex Networks at Texas Southern University.

Tensor Arithmetic, Geometric and Mathematic Principles of Fluid Mechanics in Implementation of Direct Computational Experiments

NASA Astrophysics Data System (ADS)

Bogdanov, Alexander; Khramushin, Vasily

2016-02-01

The architecture of a digital computing system determines the technical foundation of a unified mathematical language for exact arithmetic-logical description of phenomena and laws of continuum mechanics for applications in fluid mechanics and theoretical physics. The deep parallelization of the computing processes results in functional programming at a new technological level, providing traceability of the computing processes with automatic application of multiscale hybrid circuits and adaptive mathematical models for the true reproduction of the fundamental laws of physics and continuum mechanics.

Quantum informatics paradigms and tools for QIPC

NASA Astrophysics Data System (ADS)

Gruska, Jozef

2006-11-01

Quantum information processing and communication (QIPC) theory has developed recently very fast and brought a variety of interesting and important results of the great value also for the whole area of quantum physics. One can also say that the field of QIPC has been so far mainly theory driven and the experiments have been mostly done to show that it is indeed possible, and how difficult is to make it, what theory shows as possible. One of the main reasons for such a fast and successful development of the QIPC science is the fact that paradigms, models, concepts, value system, as well as methods and results of the (theoretical) informatics have been intensively used. The goal of this paper is to go behind this successful crusade and applications of the informatics for QIPC and to present, analyse and illustrate the main ideas, concepts, methods and tools that have been involved. All that should help more physics-oriented researchers in QIPC to understand that in order to explore the quantum world, new paradigms, concepts, models and so on are now available, and they could and should be used, due to the progress in (theoretical) informatics. Our concentration will be not only on what has been achieved, but even more on the main new challenges. In doing that we will concentrate more on the backgrounds, motivations, goals and implications than on the very technical results.

An Analysis of Machine- and Human-Analytics in Classification.

PubMed

Tam, Gary K L; Kothari, Vivek; Chen, Min

2017-01-01

In this work, we present a study that traces the technical and cognitive processes in two visual analytics applications to a common theoretic model of soft knowledge that may be added into a visual analytics process for constructing a decision-tree model. Both case studies involved the development of classification models based on the "bag of features" approach. Both compared a visual analytics approach using parallel coordinates with a machine-learning approach using information theory. Both found that the visual analytics approach had some advantages over the machine learning approach, especially when sparse datasets were used as the ground truth. We examine various possible factors that may have contributed to such advantages, and collect empirical evidence for supporting the observation and reasoning of these factors. We propose an information-theoretic model as a common theoretic basis to explain the phenomena exhibited in these two case studies. Together we provide interconnected empirical and theoretical evidence to support the usefulness of visual analytics.

Fuzzy spaces topology change as a possible solution to the black hole information loss paradox

NASA Astrophysics Data System (ADS)

Silva, C. A. S.

2009-06-01

The black hole information loss paradox is one of the most intricate problems in modern theoretical physics. A proposal to solve this is one related with topology change. However it has found some obstacles related to unitarity and cluster decomposition (locality). In this Letter we argue that modelling the black hole's event horizon as a noncommutative manifold - the fuzzy sphere - we can solve the problems with topology change, getting a possible solution to the black hole information loss paradox.

Computational Studies for Underground Coal Gasification (UCG) Process

NASA Astrophysics Data System (ADS)

Chatterjee, Dipankar

2017-07-01

Underground coal gasification (UCG) is a well proven technology in order to access the coal lying either too deep underground, or is otherwise too costly to be extracted using the conventional mining methods. UCG product gas is commonly used as a chemical feedstock or as fuel for power generation. During the UCG process, a cavity is formed in the coal seam during its conversion to gaseous products. The cavity grows in a three-dimensional fashion as the gasification proceeds. The UCG process is indeed a result of several complex interactions of various geo-thermo-mechanical processes such as the fluid flow, heat and mass transfer, chemical reactions, water influx, thermo-mechanical failure, and other geological aspects. The rate of the growth of this cavity and its shape will have a significant impact on the gas flow patterns, chemical kinetics, temperature distributions, and finally the quality of the product gas. It has been observed that there is insufficient information available in the literature to provide clear insight into these issues. It leaves us with a great opportunity to investigate and explore the UCG process, both from the experimental as well as theoretical perspectives. In the development and exploration of new research, experiment is undoubtedly very important. However, due to the excessive cost involvement with experimentation it is not always recommended for the complicated process like UCG. Recently, with the advent of the high performance computational facilities it is quite possible to make alternative experimentation numerically of many physically involved problems using certain computational tools like CFD (computational fluid dynamics). In order to gain a comprehensive understanding of the underlying physical phenomena, modeling strategies have frequently been utilized for the UCG process. Keeping in view the above, the various modeling strategies commonly deployed for carrying out mathematical modeling of UCG process are described here in a concise manner. The available strategies are categorized in several groups and their salient features are discussed in order to have a good understanding of the underlying physical phenomena. This would likely to be a valuable documentation in order to understand the physical process of UCG and will pave to formulate new and involved modeling and simulation techniques for computationally modeling the UCG process.

Two Photon Absorption And Refraction in Bulk of the Semiconducting Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumari, Vinay; Department of Physics, DCRUST Murthal, Haryana; Kumar, Vinod

2011-10-20

Fast electronic detection systems have opened up a number of new fields like nonlinear optics, optical communication, coherent optics, optical bistability, two/four wave mixing. The interest in this field has been stimulated by the importance of multiphoton processes in many fundamental aspects of physics. It has proved to be an invaluable tool for determining the optical and electronic properties of the solids because of the fact that one gets the information about the bulk of the material rather than the surface one. In this paper we report, the measurement of the nonlinear absorption and refraction from the band gap tomore » half-band gap region of bulk of semiconductors in the direct and indirect band gap crystals with nanosecond laser. The measured theoretical calculated values of two-photon absorption coefficients ({beta}) and nonlinear refraction n{sub 2}({omega}) of direct band gap crystal match the earlier reported theoretical predictions. By making use of these theoretical calculated values, we have estimated {beta} and n{sub 2}({omega}) in the case of indirect band gap crystals. Low value of absorption coefficient in case of indirect band gap crystals have been attributed to phonon assisted transition while reduction in nonlinear refraction is due to the rise in saturation taking place in the absorption.« less

Experimental and Theoretical Investigations of the Solidification of Eutectic Al-Si Alloy

NASA Technical Reports Server (NTRS)

Sen, S.; Catalina, A. V.; Rose, M. Franklin (Technical Monitor)

2001-01-01

The eutectic alloys have a wide spectrum of applications due to their good castability and physical and mechanical properties. The interphase spacing resulting during solidification is an important microstructural feature that significantly influences the mechanical behavior of the material. Thus, knowledge of the evolution of the interphase spacing during solidification is necessary in order to properly design the solidification process and optimize the material properties. While the growth of regular eutectics is rather well understood, the irregular eutectics such as Al-Si or Fe-graphite exhibit undercoolings and lamellar spacings much larger than those theoretically predicted. Despite of a considerable amount of experimental and theoretical work a clear understanding of the true mechanism underlying the spacing selection in irregular eutectics is yet to be achieved. A new experimental study of the solidification of the eutectic Al-Si alloy will be reported in this paper. The measured interface undercoolings and lamellar spacing will be compared to those found in the literature in order to get more general information regarding the growth mechanism of irregular eutectics. A modification of the present theory of the eutectic growth is also proposed. The results of the modified mathematical model, accounting for a non-isothermal solid/liquid interface, will be compared to the experimental measurements.

Learning Physical Domains: Toward a Theoretical Framework.

DTIC Science & Technology

1986-12-01

advanced ids o the iaime doinain in containing more information, especially perceptual " ’It. iho lI b1 rwt... tI hat. psychboigists by no means...Acquisitions Dr Kenneth D Forbus 4833 Rugby Avenue University of Illinois Dr Robert Glaser Bethesda, MD 20014 Department of Computer Science Learning

Central Auditory Processing Disorders: Is It a Meaningful Construct or a Twentieth Century Unicorn?

ERIC Educational Resources Information Center

Kamhi, Alan G.; Beasley, Daniel S.

1985-01-01

The article demonstrates how professional and theoretical perspectives (including psycholinguistics, behaviorist, and information processing perspectives) significantly influence the manner in which central auditory processing is viewed, assessed, and remediated. (Author/CL)

Efficient retrieval of landscape Hessian: Forced optimal covariance adaptive learning

NASA Astrophysics Data System (ADS)

Shir, Ofer M.; Roslund, Jonathan; Whitley, Darrell; Rabitz, Herschel

2014-06-01

Knowledge of the Hessian matrix at the landscape optimum of a controlled physical observable offers valuable information about the system robustness to control noise. The Hessian can also assist in physical landscape characterization, which is of particular interest in quantum system control experiments. The recently developed landscape theoretical analysis motivated the compilation of an automated method to learn the Hessian matrix about the global optimum without derivative measurements from noisy data. The current study introduces the forced optimal covariance adaptive learning (FOCAL) technique for this purpose. FOCAL relies on the covariance matrix adaptation evolution strategy (CMA-ES) that exploits covariance information amongst the control variables by means of principal component analysis. The FOCAL technique is designed to operate with experimental optimization, generally involving continuous high-dimensional search landscapes (≳30) with large Hessian condition numbers (≳104). This paper introduces the theoretical foundations of the inverse relationship between the covariance learned by the evolution strategy and the actual Hessian matrix of the landscape. FOCAL is presented and demonstrated to retrieve the Hessian matrix with high fidelity on both model landscapes and quantum control experiments, which are observed to possess nonseparable, nonquadratic search landscapes. The recovered Hessian forms were corroborated by physical knowledge of the systems. The implications of FOCAL extend beyond the investigated studies to potentially cover other physically motivated multivariate landscapes.

Using the EZ-Diffusion Model to Score a Single-Category Implicit Association Test of Physical Activity

PubMed Central

Rebar, Amanda L.; Ram, Nilam; Conroy, David E.

2014-01-01

Objective The Single-Category Implicit Association Test (SC-IAT) has been used as a method for assessing automatic evaluations of physical activity, but measurement artifact or consciously-held attitudes could be confounding the outcome scores of these measures. The objective of these two studies was to address these measurement concerns by testing the validity of a novel SC-IAT scoring technique. Design Study 1 was a cross-sectional study, and study 2 was a prospective study. Method In study 1, undergraduate students (N = 104) completed SC-IATs for physical activity, flowers, and sedentary behavior. In study 2, undergraduate students (N = 91) completed a SC-IAT for physical activity, self-reported affective and instrumental attitudes toward physical activity, physical activity intentions, and wore an accelerometer for two weeks. The EZ-diffusion model was used to decompose the SC-IAT into three process component scores including the information processing efficiency score. Results In study 1, a series of structural equation model comparisons revealed that the information processing score did not share variability across distinct SC-IATs, suggesting it does not represent systematic measurement artifact. In study 2, the information processing efficiency score was shown to be unrelated to self-reported affective and instrumental attitudes toward physical activity, and positively related to physical activity behavior, above and beyond the traditional D-score of the SC-IAT. Conclusions The information processing efficiency score is a valid measure of automatic evaluations of physical activity. PMID:25484621

The application of information theory for the research of aging and aging-related diseases.

PubMed

Blokh, David; Stambler, Ilia

2017-10-01

This article reviews the application of information-theoretical analysis, employing measures of entropy and mutual information, for the study of aging and aging-related diseases. The research of aging and aging-related diseases is particularly suitable for the application of information theory methods, as aging processes and related diseases are multi-parametric, with continuous parameters coexisting alongside discrete parameters, and with the relations between the parameters being as a rule non-linear. Information theory provides unique analytical capabilities for the solution of such problems, with unique advantages over common linear biostatistics. Among the age-related diseases, information theory has been used in the study of neurodegenerative diseases (particularly using EEG time series for diagnosis and prediction), cancer (particularly for establishing individual and combined cancer biomarkers), diabetes (mainly utilizing mutual information to characterize the diseased and aging states), and heart disease (mainly for the analysis of heart rate variability). Few works have employed information theory for the analysis of general aging processes and frailty, as underlying determinants and possible early preclinical diagnostic measures for aging-related diseases. Generally, the use of information-theoretical analysis permits not only establishing the (non-linear) correlations between diagnostic or therapeutic parameters of interest, but may also provide a theoretical insight into the nature of aging and related diseases by establishing the measures of variability, adaptation, regulation or homeostasis, within a system of interest. It may be hoped that the increased use of such measures in research may considerably increase diagnostic and therapeutic capabilities and the fundamental theoretical mathematical understanding of aging and disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mathematics and Information Retrieval.

ERIC Educational Resources Information Center

Salton, Gerald

1979-01-01

Examines the main mathematical approaches to information retrieval, including both algebraic and probabilistic models, and describes difficulties which impede formalization of information retrieval processes. A number of developments are covered where new theoretical understandings have directly led to improved retrieval techniques and operations.…

Doing what's right: A grounded theory of ethical decision-making in occupational therapy.

PubMed

VanderKaay, Sandra; Letts, Lori; Jung, Bonny; Moll, Sandra E

2018-04-20

Ethical decision-making is an important aspect of reasoning in occupational therapy practice. However, the process of ethical decision-making within the broader context of reasoning is yet to be clearly explicated. The purpose of this study was to advance a theoretical understanding of the process by which occupational therapists make ethical decisions in day-to-day practice. A constructivist grounded theory approach was adopted, incorporating in-depth semi-structured interviews with 18 occupational therapists from a range of practice settings and years of experience. Initially, participants nominated as key informants who were able to reflect on their decision-making processes were recruited. Theoretical sampling informed subsequent stages of data collection. Participants were asked to describe their process of ethical decision-making using scenarios from clinical practice. Interview transcripts were analyzed using a systematic process of initial then focused coding, and theoretical categorization to construct a theory regarding the process of ethical decision-making. An ethical decision-making prism was developed to capture three main processes: Considering the Fundamental Checklist, Consulting Others, and Doing What's Right. Ethical decision-making appeared to be an inductive and dialectical process with the occupational therapist at its core. Study findings advance our understanding of ethical decision-making in day-to-day clinical practice.

Theoretical Investigation of the Effects of Atmospheric Gravity Waves on the Hydroxyl Emissions of the Atmosphere.

DTIC Science & Technology

1979-12-31

of response etc. have been treated by Thome (1968), Testud and Francois (1971), Klostermeyer (1972a,b) and Porter and Tuan (1974). With the ex...and provided a suitable physical -2- -- 2 - -- explanation. Subsequent theoretical papers by Testud and Francois (1971), Klostermeyer (1971a,b) and...01 airglow emission intensity on Oct. 28-29, 1961, Nature 195, 481-482 (1962). (26) Testud , J. and P. Francois, Importance of diffusion processes in

PREFACE: Quantum information processing

NASA Astrophysics Data System (ADS)

Briggs, Andrew; Ferry, David; Stoneham, Marshall

2006-05-01

Microelectronics and the classical information technologies transformed the physics of semiconductors. Photonics has given optical materials a new direction. Quantum information technologies, we believe, will have immense impact on condensed matter physics. The novel systems of quantum information processing need to be designed and made. Their behaviours must be manipulated in ways that are intrinsically quantal and generally nanoscale. Both in this special issue and in previous issues (see e.g., Spiller T P and Munro W J 2006 J. Phys.: Condens. Matter 18 V1-10) we see the emergence of new ideas that link the fundamentals of science to the pragmatism of market-led industry. We hope these papers will be followed by many others on quantum information processing in the Journal of Physics: Condensed Matter.

Theoretical modeling of the electronic structure and exchange interactions in Cu(II)Pc

NASA Astrophysics Data System (ADS)

Wu, Wei; Fisher, A. J.; Harrison, N. M.; Wang, Hai; Wu, Zhenlin; Gardener, Jules; Heutz, Sandrine; Jones, Tim; Aeppli, Gabriel

2012-12-01

We calculate the electronic structure and exchange interactions in a copper(II)phthalocyanine (Cu(II)Pc) crystal as a one-dimensional molecular chain using hybrid exchange density functional theory (DFT). In addition, the intermolecular exchange interactions are also calculated in a molecular dimer using Green's function perturbation theory (GFPT) to illustrate the underlying physics. We find that the exchange interactions depend strongly on the stacking angle, but weakly on the sliding angle (defined in the text). The hybrid DFT calculations also provide an insight into the electronic structure of the Cu(II)Pc molecular chain and demonstrate that on-site electron correlations have a significant effect on the nature of the ground state, the band gap and magnetic excitations. The exchange interactions predicted by our DFT calculations and GFPT calculations agree qualitatively with the recent experimental results on newly found η-Cu(II)Pc and the previous results for the α- and β-phases. This work provides a reliable theoretical basis for the further application of Cu(II)Pc to molecular spintronics and organic-based quantum information processing.

Theoretical modeling of the electronic structure and exchange interactions in a Cu(II)Pc one-dimensional chain

NASA Astrophysics Data System (ADS)

Wu, Wei; Fisher, A. J.; Harrison, N. M.

2011-07-01

We calculate the electronic structure and exchange interactions in a copper(II)phthalocyanine [Cu(II)Pc] crystal as a one-dimensional molecular chain using hybrid exchange density functional theory (DFT). In addition, the intermolecular exchange interactions are also calculated in a molecular dimer using Green’s function perturbation theory (GFPT) to illustrate the underlying physics. We find that the exchange interactions depend strongly on the stacking angle, but weakly on the sliding angle (defined in the text). The hybrid DFT calculations also provide an insight into the electronic structure of the Cu(II)Pc molecular chain and demonstrate that on-site electron correlations have a significant effect on the nature of the ground state, the band gap, and magnetic excitations. The exchange interactions predicted by our DFT calculations and GFPT calculations agree qualitatively with the recent experimental results on newly found η-Cu(II)Pc and the previous results for the α and β phases. This work provides a reliable theoretical basis for the further application of Cu(II)Pc to molecular spintronics and organic-based quantum information processing.

Magnetic Reconnection: Theoretical and Observational Perspectives: Preface

NASA Technical Reports Server (NTRS)

Lewis, W. S.; Antiochos, S. K,; Drake, J. F.

2011-01-01

Magnetic reconnection is a fundamental plasma-physical process by which energy stored in a magnetic field is converted, often explosively, into heat and the kinetic energy of the charged particles that constitute the plasma. It occurs in a variety of astrophysical settings, ranging from the solar corona to pulsar magnetospheres and winds, as well as in laboratory fusion experiments, where it is responsible for sawtooth crashes. First proposed by R.G. Giovanelli in the late I 940s as the mechanism responsible for solar flares, magnetic reconnection was invoked at the beginning of the space age to explain not just solar flares but also the transfer of energy, mass, and momentum from the solar wind to Earth's magnetosphere and the subsequent storage and release of the transferred energy in the magnetotai\\. During the half century or so that has followed the seminal theoretical works by J.W. Dungey, P.A. Sweet, E.N. Parker, and H.E. Petschek, in-situ measurements by Earth-orbiting satellites and remote-sensing observations of the solar corona have provided a growing body of evidence for the occurrence of reconnection at the Sun, in the solar wind, and in the near-Earth space environment. The last thirty years have also seen the development of laboratory reconnection experiments at a number of institutions. In parallel with the efforts of experimentalists in both space and laboratory plasma physics, theorists have investigated, analytically and with the help of increasingly powerful MHD, hybrid, and kinetic numerical simulations, the structure of the diffusion region, the factors controlling the rate, onset, and cessation of reconnection, and the detailed physics that enables the demagnetization of the ions and electrons and the topological reconfiguration of the magnetic field. Moreover, the scope of theoretical reconnection studies has been extended well beyond solar system and laboratory plasmas to include more exotic astrophysical plasma systems whose strong (10(exp 14)-10(exp 15) G) magnetic fields require that models of reconnection in these systems incorporate quantum electrodynamical, special relativistic, and radiative effects. The papers collected in this topical issue of Space Science Reviews cover different aspects of recent theoretical and observational work on magnetic reconnection in solar and space physics, astrophysics, and laboratory plasma physics. They derive from presentations given at a workshop on magnetic reconnection held in the Yosemite National Park, February 8-12,2010. The intent of the workshop was to stimulate, through a combination of tutorial talks, shorter focused talks, and extensive informal discussions, an interdisciplinary dialogue among members of the different research communities working on the problem of magnetic reconnection. One of the motivating considerations for holding the workshop was its relevance to NASA's Magnetospheric Multiscale (MMS) mission, scheduled for launch in 2014. The four identically instrumented MMS spacecraft are designed to study reconnect ion in Earth's magnetosphere and, specifically, to probe the electron diffusion region in order to determine the microphysical processes that enable the change in the topology of the magnetic field. Building on the achievements of the multi spacecraft Cluster and THEMIS missions, MMS will use the magnetosphere as an astrophysical plasma laboratory in which to test, through in-situ measurement of the plasma, energetic particles, and electric and magnetic fields, various models and theories that have emerged during the past twenty years, a period of extraordinarily productive theoretical and observational work.

First Steps in Eukaryogenesis: Physical Phenomena in the Origin and Evolution of Chromosome Structure

NASA Astrophysics Data System (ADS)

Chela-Flores, Julian

1998-04-01

Our present understanding of the origin and evolution of chromosomes differs considerably from current understanding of the origin and evolution of the cell itself. Chromosome origins have been less prominent in research, as the emphasis has not shifted so far appreciably from the phenomenon of primeval nucleic acid encapsulation to that of the origin of gene organization, expression, and regulation. In this work we discuss some reasons why preliminary steps in this direction are being taken. We have been led to examine properties that have contributed to raise the ancestral prokaryotic programmes to a level where we can appreciate in eukaryotes a clear departure from earlier themes in the evolution of the cell from the last common ancestor. We shift our point of view from evolution of cell morphology to the point of view of the genes. In particular, we focus attention on possible physical bases for the way transmission of information has evolved in eukaryotes, namely, the inactivation of whole chromosomes. The special case of the inactivation of the X chromosome in mammals is discussed, paying particular attention to the physical process of the spread of X inactivation in monotremes (platypus and echidna). When experimental data is unavailable some theoretical analysis is possible based on the idea that in certain cases collective phenomena in genetics, rather than chemical detail, are better correlates of complex chemical processes.

On the Concept of Information and Its Role in Nature

NASA Astrophysics Data System (ADS)

Roederer, Juan G.

2003-03-01

In this article we address some fundamental questions concerning information: Can the existing laws of physics adequately deal with the most striking property of information, namely to cause specific changes in the structure and energy flows of a complex system, without the information in itself representing fields, forces or energy in any of their characteristic forms? Or is information irreducible to the laws of physics and chemistry? Are information and complexity related concepts? Does the Universe, in its evolution, constantly generate new information? Or are information and information-processing exclusive attributes of living systems, related to the very definition of life? If that were the case, what happens with the physical meanings of entropy in statistical mechanics or wave function in quantum mechanics? How many distinct classes of information and information processing do exist in the biological world? How does information appear in Darwinian evolution? Does the human brain have unique properties or capabilities in terms of information processing? In what ways does information processing bring about human self-consciousness? We shall introduce the meaning of "information" in a way that is detached from human technological systems and related algorithms and semantics, and that is not based on any mathematical formula. To accomplish this we turn to the concept of interaction as the basic departing point, and identify two fundamentally different classes, with information and information-processing appearing as the key discriminator: force-field driven interactions between elementary particles and ensembles of particles in the macroscopic physical domain, and information-based interactions between certain kinds of complex systems that form the biological domain. We shall show that in an abiotic world, information plays no role; physical interactions just happen, they are driven by energy exchange between the interacting parts and do not require any operations of information processing. Information only enters the non-living physical world when a living thing interacts with it-and when a scientist extracts information through observation and measurement. But for living organisms, information is the very essence of their existence: to maintain a long-term state of unstable thermodynamic equilibrium with its surroundings, consistently increase its organization and reproduce, an organism has to rely on information-based interactions in which form or pattern, not energy, is the controlling factor. This latter class comprises biomolecular information processes controlling the metabolism, growth, multiplication and differentiation of cells, and neural information processes controlling animal behavior and intelligence. The only way new information can appear is through the process of biological evolution and, in the short term, through sensory acquisition and the manipulation of images in the nervous system. Non-living informational systems such as books, computers, AI systems and other artifacts, as well as living organisms that are the result of breeding or cloning, are planned by human beings and will not be considered here.

The uses of isospin in early nuclear and particle physics

NASA Astrophysics Data System (ADS)

Borrelli, Arianna

2017-11-01

This paper reconstructs the early history of isospin up to and including its employment in 1951sbnd 52 to conceptualize high-energy pion-proton scattering. Studying the history of isospin serves as an entry point for investigating the interplay of theoretical and experimental practices in early nuclear and particle physics, showing the complexity of processes of knowledge construction which have often been presented as straightforward both in physicists' recollections and in the historiography of science. The story of isospin has often been told in terms of the discovery of the first ;intrinsic property; of elementary particles, but I will argue that the isospin formalism emerged and was further developed because it proved to be a useful tool to match theory and experiment within the steadily broadening field of high-energy (nuclear) physics. Isospin was variously appropriated and adapted in the course of two decades, before eventually the physical-mathematical implications of its uses started being spelled out. The case study also highlights some interesting features of high-energy physics around 1950: the contribution to post-war research of theoretical methods developed before and during the war, the role of young theoretical post-docs in mediating between theorists and experimenters, and the importance of traditional formalisms such as those of spin and angular momentum as a template both for formalizing and conceptualizing experimental results.

PREFACE: The International Conference on Theoretical Physics `Dubna-Nano2008'

NASA Astrophysics Data System (ADS)

Osipov, V. A.; Nesterenko, V. O.; Shukrinov, Y. M.

2008-07-01

The International Conference on Theoretical Physics `Dubna-Nano2008' was held on 7-11 July 2008 at the Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia. The conference provided the opportunity for the presentation and discussion of theoretical and experimental advances in the rapidly growing area of the nanophysics, with the accent on its theoretical aspects. The multidisciplinary character of the conference allowed an effective exchange of ideas between different areas of nanophysics. The following topics were covered: carbon nanosystems (fullerenes, nanotubes, graphene), quantum dots, electron and spin transport, spectroscopy and dynamics of atomic clusters, Josephson junctions, bio-complexes, and applications of nanosystems. Approximately 90 scientists from 16 countries participated in the conference. The program included 48 oral talks and 40 posters. The 51 contributions are included in this proceedings. We would like to express our gratitude to all participants for their presentations and discussions, which made the conference so successful. We are deeply indebted to the members of the International Advisory Committee (Professors T Ando, S Datta, A V Eletskii, J Fabian, F Guinea, P Hawrylak, K Kadowaki, T Koyama, Yu I Latushev, N F Pedersen, P-G Reinhard, J M Rost, A Ya Vul') and the Local Organizing Committee for their fruitful work. The financial support of BLTP JINR, Russian Foundation for Basic Research, Heisenberg-Landau Program and Bogoliubov-Infeld Program was of a great importance. Additional information about `Dubna-Nano2008' is available at the homepage http://theor.jinr.ru/~nano08. Vladimir Osipov, Valentin Nesterenko and Yury Shukrinov Editors

PREFACE International Conference on Theoretical Physics Dubna-Nano 2010

NASA Astrophysics Data System (ADS)

Osipov, Vladimir; Nesterenko, Valentin; Shukrinov, Yury

2010-11-01

The International Conference on Theoretical Physics 'Dubna-Nano2010' was held on 5-10 July 2010, at the Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia. The previous conference of this series was at Dubna in 2008. The conference provided the opportunity for the presentation and discussion of theoretical and experimental advances in the rapidly growing area of nanophysics, with the accent on its theoretical aspects. The multidisciplinary character of the conference allowed an effective exchange of ideas between different areas of nanophysics. The following topics were covered: carbon nanosystems (graphene, nanotubes, fullerenes), quantum dots, quantum transport, spectroscopy and dynamics of atomic clusters, Josephson junctions, modelling, applications and perspectives. Approximately 120 scientists from 26 countries participated in the conference. The program included 63 oral talks and 70 posters. The 62 contributions are included in these proceedings. We would like to express our gratitude to all participants for their presentations and discussions, which made the conference indeed successful. We are deeply indebted to the members of the International Advisory Committee (Professors T Ando, J Fabian, F Guinea, P Hawrylak, K Kadowaki, T Koyama, Yu I Latushev, Yu E Lozovik, M Machida, B K Nikolic, N F Pedersen, P-G Reinhard, J M Rost, A Ya Vul') and the Local Organizing Committee for their fruitful work. The financial support of BLTP JINR, Russian Foundation for Basic Research, Heisenberg-Landau Program and Bogoliubov-Infeld Program was of a great importance. Additional information about 'Dubna-Nano2010' is available at the homepage http://theor.jinr.ru/~nano10. Vladimir Osipov, Valentin Nesterenko and Yury Shukrinov Editors

Mutual information, neural networks and the renormalization group

NASA Astrophysics Data System (ADS)

Koch-Janusz, Maciej; Ringel, Zohar

2018-06-01

Physical systems differing in their microscopic details often display strikingly similar behaviour when probed at macroscopic scales. Those universal properties, largely determining their physical characteristics, are revealed by the powerful renormalization group (RG) procedure, which systematically retains `slow' degrees of freedom and integrates out the rest. However, the important degrees of freedom may be difficult to identify. Here we demonstrate a machine-learning algorithm capable of identifying the relevant degrees of freedom and executing RG steps iteratively without any prior knowledge about the system. We introduce an artificial neural network based on a model-independent, information-theoretic characterization of a real-space RG procedure, which performs this task. We apply the algorithm to classical statistical physics problems in one and two dimensions. We demonstrate RG flow and extract the Ising critical exponent. Our results demonstrate that machine-learning techniques can extract abstract physical concepts and consequently become an integral part of theory- and model-building.

The theoretical cognitive process of visualization for science education.

PubMed

Mnguni, Lindelani E

2014-01-01

The use of visual models such as pictures, diagrams and animations in science education is increasing. This is because of the complex nature associated with the concepts in the field. Students, especially entrant students, often report misconceptions and learning difficulties associated with various concepts especially those that exist at a microscopic level, such as DNA, the gene and meiosis as well as those that exist in relatively large time scales such as evolution. However the role of visual literacy in the construction of knowledge in science education has not been investigated much. This article explores the theoretical process of visualization answering the question "how can visual literacy be understood based on the theoretical cognitive process of visualization in order to inform the understanding, teaching and studying of visual literacy in science education?" Based on various theories on cognitive processes during learning for science and general education the author argues that the theoretical process of visualization consists of three stages, namely, Internalization of Visual Models, Conceptualization of Visual Models and Externalization of Visual Models. The application of this theoretical cognitive process of visualization and the stages of visualization in science education are discussed.

Generation of a non-zero discord bipartite state with classical second-order interference.

PubMed

Choi, Yujun; Hong, Kang-Hee; Lim, Hyang-Tag; Yune, Jiwon; Kwon, Osung; Han, Sang-Wook; Oh, Kyunghwan; Kim, Yoon-Ho; Kim, Yong-Su; Moon, Sung

2017-02-06

We report an investigation on quantum discord in classical second-order interference. In particular, we theoretically show that a bipartite state with D = 0.311 of discord can be generated via classical second-order interference. We also experimentally verify the theory by obtaining D = 0.197 ± 0.060 of non-zero discord state. Together with the fact that the nonclassicalities originated from physical constraints and information theoretic perspectives are not equivalent, this result provides an insight to understand the nature of quantum discord.

Potential energy landscapes identify the information-theoretic nature of the epigenome

PubMed Central

Jenkinson, Garrett; Pujadas, Elisabet; Goutsias, John; Feinberg, Andrew P.

2017-01-01

Epigenetics studies genomic modifications carrying information independent of DNA sequence heritable through cell division. In 1940, Waddington coined the term “epigenetic landscape” as a metaphor for pluripotency and differentiation, but methylation landscapes have not yet been rigorously computed. By using principles of statistical physics and information theory, we derive epigenetic energy landscapes from whole-genome bisulfite sequencing data that allow us to quantify methylation stochasticity genome-wide using Shannon’s entropy and associate entropy with chromatin structure. Moreover, we consider the Jensen-Shannon distance between sample-specific energy landscapes as a measure of epigenetic dissimilarity and demonstrate its effectiveness for discerning epigenetic differences. By viewing methylation maintenance as a communications system, we introduce methylation channels and show that higher-order chromatin organization can be predicted from their informational properties. Our results provide a fundamental understanding of the information-theoretic nature of the epigenome that leads to a powerful approach for studying its role in disease and aging. PMID:28346445

Attachment and the Processing of Social Information across the Life Span: Theory and Evidence

ERIC Educational Resources Information Center

Dykas, Matthew J.; Cassidy, Jude

2011-01-01

Researchers have used J. Bowlby's (1969/1982, 1973, 1980, 1988) attachment theory frequently as a basis for examining whether experiences in close personal relationships relate to the processing of social information across childhood, adolescence, and adulthood. We present an integrative life-span-encompassing theoretical model to explain the…

The Animadora Project: Identifying factors related to the promotion of physical activity among Mexican Americans with diabetes

PubMed Central

Ingram, Maia; Ruis, Maricruz; Mayorga, Maria Theresa; Rosales, Cecilia

2015-01-01

Purpose There is a dearth of information about factors related to physical activity among Mexican Americans with diabetes. Self efficacy and social support are associated with physical activity, however little is known about their role within different cultural groups. Design Focus groups were used to identify factors that motivate walking. Setting Two Mexican American communities located in Tucson, Arizona. Subjects Individuals who attended diabetes education. Intervention A community-based provider organized walking groups with people who previously attended diabetes classes. Walkers participated in focus groups exploring themes related to their experience. Measures Self efficacy, social support, and collective efficacy. Grounded theory was used to analyze focus group results using two rounds of analysis; the first identifying references to self efficacy and social support and the second adding collective efficacy as a theoretical basis for walking. Results Among 43 eligible participants, 20 participated in focus groups. Social support was expressed as commitment and companionship. Walkers demonstrated a high level of self efficacy for walking. Development of group identity/social cohesion was also a motivator to walk. Collective efficacy emerged as an applicable theoretical model encompassing these themes and their interrelationship. Conclusion Collective efficacy, or the belief that the group can improve their lives through collective effort, is a viable theoretical construct in the development of physical activity interventions targeting Mexican Americans with diabetes. PMID:19601479

Special issue on cluster algebras in mathematical physics

NASA Astrophysics Data System (ADS)

Di Francesco, Philippe; Gekhtman, Michael; Kuniba, Atsuo; Yamazaki, Masahito

2014-02-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to cluster algebras in mathematical physics. Over the ten years since their introduction by Fomin and Zelevinsky, the theory of cluster algebras has witnessed a spectacular growth, first and foremost due to the many links that have been discovered with a wide range of subjects in mathematics and, increasingly, theoretical and mathematical physics. The main motivation of this special issue is to gather together reviews, recent developments and open problems, mainly from a mathematical physics viewpoint, into a single comprehensive issue. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will consist of invited review articles and contributed papers containing new results on the interplays of cluster algebras with mathematical physics. Editorial policy The Guest Editors for this issue are Philippe Di Francesco, Michael Gekhtman, Atsuo Kuniba and Masahito Yamazaki. The areas and topics for this issue include, but are not limited to: discrete integrable systems arising from cluster mutations cluster structure on Poisson varieties cluster algebras and soliton interactions cluster positivity conjecture Y-systems in the thermodynamic Bethe ansatz and Zamolodchikov's periodicity conjecture T-system of transfer matrices of integrable lattice models dilogarithm identities in conformal field theory wall crossing in 4d N = 2 supersymmetric gauge theories 4d N = 1 quiver gauge theories described by networks scattering amplitudes of 4d N = 4 theories 3d N = 2 gauge theories described by flat connections on 3-manifolds integrability of dimer/Ising models on graphs. All contributions will be refereed and processed according to the usual procedure of the journal. Guidelines for preparation of contributions The deadline for contributed papers is 31 March 2014. This deadline will allow the special issue to appear at the end of 2014. There is no strict regulation on article size, but as a guide the preferable size is 15-30 pages for contributed papers and 40-60 pages for reviews. Further advice on publishing your work in Journal of Physics A may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via ScholarOne Manuscripts, quoting 'JPhysA special issue on cluster algebras in mathematical physics'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Special issue on cluster algebras in mathematical physics

NASA Astrophysics Data System (ADS)

Di Francesco, Philippe; Gekhtman, Michael; Kuniba, Atsuo; Yamazaki, Masahito

2013-12-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to cluster algebras in mathematical physics. Over the ten years since their introduction by Fomin and Zelevinsky, the theory of cluster algebras has witnessed a spectacular growth, first and foremost due to the many links that have been discovered with a wide range of subjects in mathematics and, increasingly, theoretical and mathematical physics. The main motivation of this special issue is to gather together reviews, recent developments and open problems, mainly from a mathematical physics viewpoint, into a single comprehensive issue. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will consist of invited review articles and contributed papers containing new results on the interplays of cluster algebras with mathematical physics. Editorial policy The Guest Editors for this issue are Philippe Di Francesco, Michael Gekhtman, Atsuo Kuniba and Masahito Yamazaki. The areas and topics for this issue include, but are not limited to: discrete integrable systems arising from cluster mutations cluster structure on Poisson varieties cluster algebras and soliton interactions cluster positivity conjecture Y-systems in the thermodynamic Bethe ansatz and Zamolodchikov's periodicity conjecture T-system of transfer matrices of integrable lattice models dilogarithm identities in conformal field theory wall crossing in 4d N = 2 supersymmetric gauge theories 4d N = 1 quiver gauge theories described by networks scattering amplitudes of 4d N = 4 theories 3d N = 2 gauge theories described by flat connections on 3-manifolds integrability of dimer/Ising models on graphs. All contributions will be refereed and processed according to the usual procedure of the journal. Guidelines for preparation of contributions The deadline for contributed papers is 31 March 2014. This deadline will allow the special issue to appear at the end of 2014. There is no strict regulation on article size, but as a guide the preferable size is 15-30 pages for contributed papers and 40-60 pages for reviews. Further advice on publishing your work in Journal of Physics A may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via ScholarOne Manuscripts, quoting 'JPhysA special issue on cluster algebras in mathematical physics'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Special issue on cluster algebras in mathematical physics

NASA Astrophysics Data System (ADS)

Di Francesco, Philippe; Gekhtman, Michael; Kuniba, Atsuo; Yamazaki, Masahito

2013-11-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to cluster algebras in mathematical physics. Over the ten years since their introduction by Fomin and Zelevinsky, the theory of cluster algebras has witnessed a spectacular growth, first and foremost due to the many links that have been discovered with a wide range of subjects in mathematics and, increasingly, theoretical and mathematical physics. The main motivation of this special issue is to gather together reviews, recent developments and open problems, mainly from a mathematical physics viewpoint, into a single comprehensive issue. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will consist of invited review articles and contributed papers containing new results on the interplays of cluster algebras with mathematical physics. Editorial policy The Guest Editors for this issue are Philippe Di Francesco, Michael Gekhtman, Atsuo Kuniba and Masahito Yamazaki. The areas and topics for this issue include, but are not limited to: discrete integrable systems arising from cluster mutations cluster structure on Poisson varieties cluster algebras and soliton interactions cluster positivity conjecture Y-systems in the thermodynamic Bethe ansatz and Zamolodchikov's periodicity conjecture T-system of transfer matrices of integrable lattice models dilogarithm identities in conformal field theory wall crossing in 4d N = 2 supersymmetric gauge theories 4d N = 1 quiver gauge theories described by networks scattering amplitudes of 4d N = 4 theories 3d N = 2 gauge theories described by flat connections on 3-manifolds integrability of dimer/Ising models on graphs. All contributions will be refereed and processed according to the usual procedure of the journal. Guidelines for preparation of contributions The deadline for contributed papers is 31 March 2014. This deadline will allow the special issue to appear at the end of 2014. There is no strict regulation on article size, but as a guide the preferable size is 15-30 pages for contributed papers and 40-60 pages for reviews. Further advice on publishing your work in Journal of Physics A may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via ScholarOne Manuscripts, quoting 'JPhysA special issue on cluster algebras in mathematical physics'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Elementary process and meteor train spectra

NASA Technical Reports Server (NTRS)

Ovezgeldyev, O. G.

1987-01-01

Mechanisms of excitation of individual spectral line radiation were studied experimentally and theoretically and it was demonstrated that such processes as oxidation, resonant charge exchange, dissociative recombination and others play an important part in the chemistry of excited particles. The foundation was laid toward simulating the elementary processes of meteor physics. Having a number of advantages and possibilities, this method is sure to find a wide use in the future.

Spectral Entropies as Information-Theoretic Tools for Complex Network Comparison

NASA Astrophysics Data System (ADS)

De Domenico, Manlio; Biamonte, Jacob

2016-10-01

Any physical system can be viewed from the perspective that information is implicitly represented in its state. However, the quantification of this information when it comes to complex networks has remained largely elusive. In this work, we use techniques inspired by quantum statistical mechanics to define an entropy measure for complex networks and to develop a set of information-theoretic tools, based on network spectral properties, such as Rényi q entropy, generalized Kullback-Leibler and Jensen-Shannon divergences, the latter allowing us to define a natural distance measure between complex networks. First, we show that by minimizing the Kullback-Leibler divergence between an observed network and a parametric network model, inference of model parameter(s) by means of maximum-likelihood estimation can be achieved and model selection can be performed with appropriate information criteria. Second, we show that the information-theoretic metric quantifies the distance between pairs of networks and we can use it, for instance, to cluster the layers of a multilayer system. By applying this framework to networks corresponding to sites of the human microbiome, we perform hierarchical cluster analysis and recover with high accuracy existing community-based associations. Our results imply that spectral-based statistical inference in complex networks results in demonstrably superior performance as well as a conceptual backbone, filling a gap towards a network information theory.

How an interacting many-body system tunnels through a potential barrier to open space

PubMed Central

Lode, Axel U.J.; Streltsov, Alexej I.; Sakmann, Kaspar; Alon, Ofir E.; Cederbaum, Lorenz S.

2012-01-01

The tunneling process in a many-body system is a phenomenon which lies at the very heart of quantum mechanics. It appears in nature in the form of α-decay, fusion and fission in nuclear physics, and photoassociation and photodissociation in biology and chemistry. A detailed theoretical description of the decay process in these systems is a very cumbersome problem, either because of very complicated or even unknown interparticle interactions or due to a large number of constituent particles. In this work, we theoretically study the phenomenon of quantum many-body tunneling in a transparent and controllable physical system, an ultracold atomic gas. We analyze a full, numerically exact many-body solution of the Schrödinger equation of a one-dimensional system with repulsive interactions tunneling to open space. We show how the emitted particles dissociate or fragment from the trapped and coherent source of bosons: The overall many-particle decay process is a quantum interference of single-particle tunneling processes emerging from sources with different particle numbers taking place simultaneously. The close relation to atom lasers and ionization processes allows us to unveil the great relevance of many-body correlations between the emitted and trapped fractions of the wave function in the respective processes. PMID:22869703

Incoherent Scatter Plasma Lines: Observations and Applications

NASA Astrophysics Data System (ADS)

Akbari, Hassanali; Bhatt, Asti; La Hoz, Cesar; Semeter, Joshua L.

2017-10-01

Space plasmas are host to the electrostatic Langmuir waves and a rich range of processes associated with them. Many of such processes that are of interest in micro-scale plasma physics and magnetosphere-ionosphere physics are open to investigation via incoherent scatter plasma lines—i.e., a pair of resonant peaks in the incoherent scatter radar (ISR) spectrum, symmetrically displaced from the radar transmitting frequency by about the plasma frequency, as the signature of Langmuir waves in the ISR spectrum. There now exists a large body of literature devoted to the investigation of a number of topics in ionospheric physics via plasma line theory and observation. It is the goal of this work to provide a comprehensive review of this literature, from the early theoretical works on oscillations in magnetized plasma to the recent advances in plasma line measurements and applications. This review includes detailed theoretical discussions on the intensity and frequency displacement of plasma lines. It reviews the experimental observations of plasma lines enhanced by various sources of energy and discusses the implications of the observations in the context of ionospheric physics. The review also covers the practical aspects of plasma line measurements, from measurement techniques to the applications of plasma lines in estimating the bulk parameters of the ionosphere.

Physics through the 1990s: Scientific interfaces and technological applications

NASA Technical Reports Server (NTRS)

1986-01-01

The volume examines the scientific interfaces and technological applications of physics. Twelve areas are dealt with: biological physics-biophysics, the brain, and theoretical biology; the physics-chemistry interface-instrumentation, surfaces, neutron and synchrotron radiation, polymers, organic electronic materials; materials science; geophysics-tectonics, the atmosphere and oceans, planets, drilling and seismic exploration, and remote sensing; computational physics-complex systems and applications in basic research; mathematics-field theory and chaos; microelectronics-integrated circuits, miniaturization, future trends; optical information technologies-fiber optics and photonics; instrumentation; physics applications to energy needs and the environment; national security-devices, weapons, and arms control; medical physics-radiology, ultrasonics, MNR, and photonics. An executive summary and many chapters contain recommendations regarding funding, education, industry participation, small-group university research and large facility programs, government agency programs, and computer database needs.

Recent progress of quantum communication in China (Conference Presentation)

NASA Astrophysics Data System (ADS)

Zhang, Qiang

2016-04-01

Quantum communication, based on the quantum physics, can provide information theoretical security. Building a global quantum network is one ultimate goal for the research of quantum information. Here, this talk will review the progress for quantum communication in China, including quantum key distribution over metropolitan area with untrustful relay, field test of quantum entanglement swapping over metropolitan network, the 2000 km quantum key distribution main trunk line, and satellite based quantum communication.

Geometric stability of topological lattice phases

PubMed Central

Jackson, T. S.; Möller, Gunnar; Roy, Rahul

2015-01-01

The fractional quantum Hall (FQH) effect illustrates the range of novel phenomena which can arise in a topologically ordered state in the presence of strong interactions. The possibility of realizing FQH-like phases in models with strong lattice effects has attracted intense interest as a more experimentally accessible venue for FQH phenomena which calls for more theoretical attention. Here we investigate the physical relevance of previously derived geometric conditions which quantify deviations from the Landau level physics of the FQHE. We conduct extensive numerical many-body simulations on several lattice models, obtaining new theoretical results in the process, and find remarkable correlation between these conditions and the many-body gap. These results indicate which physical factors are most relevant for the stability of FQH-like phases, a paradigm we refer to as the geometric stability hypothesis, and provide easily implementable guidelines for obtaining robust FQH-like phases in numerical or real-world experiments. PMID:26530311

Preserving information from the beginning to the end of time in a Robertson-Walker spacetime

NASA Astrophysics Data System (ADS)

Mancini, Stefano; Pierini, Roberto; Wilde, Mark M.

2014-12-01

Preserving information stored in a physical system subjected to noise can be modeled in a communication-theoretic paradigm, in which storage and retrieval correspond to an input encoding and output decoding, respectively. The encoding and decoding are then constructed in such a way as to protect against the action of a given noisy quantum channel. This paper considers the situation in which the noise is not due to technological imperfections, but rather to the physical laws governing the evolution of the Universe. In particular, we consider the dynamics of quantum systems under a 1 + 1 Robertson-Walker spacetime and find that the noise imparted to them is equivalent to the well known amplitude damping channel. Since one might be interested in preserving both classical and quantum information in such a scenario, we study trade-off coding strategies and determine a region of achievable rates for the preservation of both kinds of information. For applications beyond the physical setting studied here, we also determine a trade-off between achievable rates of classical and quantum information preservation when entanglement assistance is available.

2011 Quantum Control of Light & Matter Gordon Research Conference (July 31-August 5, 2011, Mount Holyoke College, South Hadley, MA)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas Weinacht

2011-08-05

Quantum control of light and matter is the quest to steer a physical process to a desirable outcome, employing constructive and destructive interference. Three basic questions address feasibility of quantum control: (1) The problem of controllability, does a control field exist for a preset initial and target state; (2) Synthesis, constructively finding the field that leads to the target; and (3) Optimal Control Theory - optimizing the field that carries out this task. These continue to be the fundamental theoretical questions to be addressed in the conference. How to realize control fields in the laboratory is an ongoing challenge. Thismore » task is very diverse viewing the emergence of control scenarios ranging from attoseconds to microseconds. How do the experimental observations reflect on the theoretical framework? The typical arena of quantum control is an open environment where much of the control is indirect. How are control scenarios realized in dissipative open systems? Can new control opportunities emerge? Can one null decoherence effects? An ideal setting for control is ultracold matter. The initial and final state can be defined more precisely. Coherent control unifies many fields of physical science. A lesson learned in one field can reflect on another. Currently quantum information processing has emerged as a primary target of control where the key issue is controlling quantum gate operation. Modern nonlinear spectroscopy has emerged as another primary field. The challenge is to unravel the dynamics of molecular systems undergoing strong interactions with the environment. Quantum optics where non-classical fields are to be generated and employed. Finally, coherent control is the basis for quantum engineering. These issues will be under the limelight of the Gordon conference on Quantum Control of Light and Matter.« less

Reality-Theoretical Models-Mathematics: A Ternary Perspective on Physics Lessons in Upper-Secondary School

ERIC Educational Resources Information Center

Hansson, Lena; Hansson, Örjan; Juter, Kristina; Redfors, Andreas

2015-01-01

This article discusses the role of mathematics during physics lessons in upper-secondary school. Mathematics is an inherent part of theoretical models in physics and makes powerful predictions of natural phenomena possible. Ability to use both theoretical models and mathematics is central in physics. This paper takes as a starting point that the…

Physical-chemical mechanisms of pattern formation during gastrulation

NASA Astrophysics Data System (ADS)

Bozorgui, Behnaz; Kolomeisky, Anatoly B.; Teimouri, Hamid

2018-03-01

Gastrulation is a fundamental phase during the biological development of most animals when a single layer of identical embryo cells is transformed into a three-layer structure, from which the organs start to develop. Despite a remarkable progress in quantifying the gastrulation processes, molecular mechanisms of these processes remain not well understood. Here we theoretically investigate early spatial patterning in a geometrically confined colony of embryonic stem cells. Using a reaction-diffusion model, a role of Bone-Morphogenetic Protein 4 (BMP4) signaling pathway in gastrulation is specifically analyzed. Our results show that for slow diffusion rates of BMP4 molecules, a new length scale appears, which is independent of the size of the system. This length scale separates the central region of the colony with uniform low concentrations of BMP molecules from the region near the colony edge where the concentration of signaling molecules is elevated. The roles of different components of the signaling pathway are also explained. Theoretical results are consistent with recent in vitro experiments, providing microscopic explanations for some features of early embryonic spatial patterning. Physical-chemical mechanisms of these processes are discussed.

The role of companionship, esteem, and informational support in explaining physical activity among young women in an online social network intervention.

PubMed

Cavallo, David N; Brown, Jane D; Tate, Deborah F; DeVellis, Robert F; Zimmer, Catherine; Ammerman, Alice S

2014-10-01

The primary objective of the current study was to examine the relationship between social support and physical activity within the theory of planned behavior (TPB) theoretical framework. This study used data from the Internet Support for Healthy Associations Promoting Exercise randomized controlled trial. A total of 134 female undergraduate students participated in the study, which included baseline and post measures of perceived social support for physical activity (esteem, informational, and companionship), TPB variables related to physical activity (perceived behavioral control, intention, and attitude), and physical activity behavior. Path analysis revealed a significant indirect relationship between change in companionship support and physical activity mediated by change in intention (.13, p < .01) and a significant direct relationship between change in esteem support and change in physical activity (.26, p = .03). The model explained 27% of the variance in physical activity and 59% of the variance in intention. Overall, change in social support exerted a small to medium amount of influence on change in physical activity in this modified TPB model when controlling for traditional model constructs. Encouraging companionship and esteem support should be considered as a strategy for increasing physical activity in this population.

Quantum Approach to Informatics

NASA Astrophysics Data System (ADS)

Stenholm, Stig; Suominen, Kalle-Antti

2005-08-01

An essential overview of quantum information Information, whether inscribed as a mark on a stone tablet or encoded as a magnetic domain on a hard drive, must be stored in a physical object and thus made subject to the laws of physics. Traditionally, information processing such as computation occurred in a framework governed by laws of classical physics. However, information can also be stored and processed using the states of matter described by non-classical quantum theory. Understanding this quantum information, a fundamentally different type of information, has been a major project of physicists and information theorists in recent years, and recent experimental research has started to yield promising results. Quantum Approach to Informatics fills the need for a concise introduction to this burgeoning new field, offering an intuitive approach for readers in both the physics and information science communities, as well as in related fields. Only a basic background in quantum theory is required, and the text keeps the focus on bringing this theory to bear on contemporary informatics. Instead of proofs and other highly formal structures, detailed examples present the material, making this a uniquely accessible introduction to quantum informatics. Topics covered include: * An introduction to quantum information and the qubit * Concepts and methods of quantum theory important for informatics * The application of information concepts to quantum physics * Quantum information processing and computing * Quantum gates * Error correction using quantum-based methods * Physical realizations of quantum computing circuits A helpful and economical resource for understanding this exciting new application of quantum theory to informatics, Quantum Approach to Informatics provides students and researchers in physics and information science, as well as other interested readers with some scientific background, with an essential overview of the field.

Research in Theoretical High-Energy Physics at Southern Methodist University

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olness, Fredrick; Nadolsky, Pavel

2016-08-05

The SMU Theory group has developed a strong expertise in QCD, PDFs, and incisive comparisons between collider data and theory. The group pursues realistic phenomenological calculations for high-energy processes, the highly demanded research area driven by the LHC physics. Our field has seen major discoveries in recent years from a variety of experiments, large and small, including a number recognized by Nobel Prizes. There is a wealth of novel QCD data to explore. The SMU theory group develops the most advanced and innovative tools for comprehensive analysis in applications ranging from Higgs physics and new physics searches to nuclear scattering.

Mathematics, Experiments, and Theoretical Physics: The Early Days of the Sommerfeld School

NASA Astrophysics Data System (ADS)

Eckert, Michael

1999-10-01

The names of his students read like a Who's Who of the pioneers in modern physics Peter Debye, Peter Paul Ewald, Wolfgang Pauli, Werner Heisenberg, Hans A. Bethe - to name only the most prominent. In retrospect, the success of Sommerfeld's school of modern theoretical physics tends to overshadow its less glorious beginnings. A century ago, theoretical physics was not yet considered as a distinct discipline. In this article I emphasize more the haphazard beginnings than the later achievements of Sommerfeld's school, which mirrored the state of theoretical physics before it became an independent discipline.

Development of Civic Engagement: Theoretical and Methodological Issues

ERIC Educational Resources Information Center

Lerner, Richard M.; Wang, Jun; Champine, Robey B.; Warren, Daniel J. A.; Erickson, Karl

2014-01-01

Within contemporary developmental science, models derived from relational developmental systems (RDS) metatheory emphasize that the basic process of human development involves mutually-influential relations, termed developmental regulations, between the developing individual and his or her complex and changing physical, social, and cultural…

Self-Esteem and Adjusting with Blindness: The Process of Responding to Life's Demands. Third Edition

ERIC Educational Resources Information Center

Tuttle, Dean W.; Tuttle, Naomi R.

2004-01-01

This new and expanded Third Edition analyzes blindness within the context of two overlapping theoretical constructs: the development of self-esteem and the process of adjusting to social and/or physical trauma. The book is divided into four sections. The first section, provides an overview of blindness and the essential background for subsequent…

Fuzzy spaces topology change and BH thermodynamics

NASA Astrophysics Data System (ADS)

Silva, C. A. S.; Landim, R. R.

2014-03-01

What is the ultimate fate of something that falls into a black hole? From this question arises one of the most intricate problems of modern theoretical physics: the black hole information loss paradox. Bekenstein and Hawking have been shown that the entropy in a black hole is proportional to the surface area of its event horizon, which should be quantized in a multiple of the Planck area. This led G.'t Hooft and L. Susskind to propose the holographic principle which states that all the information inside the black hole can be stored on its event horizon. From this results, one may think if the solution to the information paradox could lies in the quantum properties of the black hole horizon. One way to quantize the event horizon is to see it as a fuzzy sphere, which posses a closed relation with Hopf algebras. This relation makes possible a topology change process where a fuzzy sphere splits in two others. In this work it will be shown that, if one quantize the black hole event horizon as a fuzzy sphere taking into account its quantum symmetry properties, a topology change process to black holes can be defined without break unitarity or locality, and we can obtain a possible solution to the information paradox. Moreover, we show that this model can explain the origin of the black hole entropy, and why black holes obey a generalized second law of thermodynamics.

Synthetic electromagnetic knot in a three-dimensional skyrmion

PubMed Central

Lee, Wonjae; Gheorghe, Andrei H.; Tiurev, Konstantin; Ollikainen, Tuomas; Möttönen, Mikko; Hall, David S.

2018-01-01

Classical electromagnetism and quantum mechanics are both central to the modern understanding of the physical world and its ongoing technological development. Quantum simulations of electromagnetic forces have the potential to provide information about materials and systems that do not have conveniently solvable theoretical descriptions, such as those related to quantum Hall physics, or that have not been physically observed, such as magnetic monopoles. However, quantum simulations that simultaneously implement all of the principal features of classical electromagnetism have thus far proved elusive. We experimentally realize a simulation in which a charged quantum particle interacts with the knotted electromagnetic fields peculiar to a topological model of ball lightning. These phenomena are induced by precise spatiotemporal control of the spin field of an atomic Bose-Einstein condensate, simultaneously creating a Shankar skyrmion—a topological excitation that was theoretically predicted four decades ago but never before observed experimentally. Our results reveal the versatile capabilities of synthetic electromagnetism and provide the first experimental images of topological three-dimensional skyrmions in a quantum system. PMID:29511735

Analysis of angular momentum properties of photons emitted in fundamental atomic processes

NASA Astrophysics Data System (ADS)

Zaytsev, V. A.; Surzhykov, A. S.; Shabaev, V. M.; Stöhlker, Th.

2018-04-01

Many atomic processes result in the emission of photons. Analysis of the properties of emitted photons, such as energy and angular distribution as well as polarization, is regarded as a powerful tool for gaining more insight into the physics of corresponding processes. Another characteristic of light is the projection of its angular momentum upon propagation direction. This property has attracted a special attention over the past decades due to studies of twisted (or vortex) light beams. Measurements being sensitive to this projection may provide valuable information about the role of angular momentum in the fundamental atomic processes. Here we describe a simple theoretical method for determination of the angular momentum properties of the photons emitted in various atomic processes. This method is based on the evaluation of expectation value of the total angular momentum projection operator. To illustrate the method, we apply it to the textbook examples of plane-wave, spherical-wave, and Bessel light. Moreover, we investigate the projection of angular momentum for the photons emitted in the process of the radiative recombination with ionic targets. It is found that the recombination photons do carry a nonzero projection of the orbital angular momentum.

PREFACE: 2nd International Workshop on Theoretical and Computational Physics (IWTCP-2): Modern Methods and Latest Results in Particle Physics, Nuclear Physics and Astrophysics and the 39th National Conference on Theoretical Physics (NCTP-39)

NASA Astrophysics Data System (ADS)

Hoang, Trinh Xuan; Ky, Nguyen Anh; Lan, Nguyen Tri; Viet, Nguyen Ai

2015-06-01

This volume contains selected papers presented at the 2nd International Workshop on Theoretical and Computational Physics (IWTCP-2): Modern Methods and Latest Results in Particle Physics, Nuclear Physics and Astrophysics and the 39th National Conference on Theoretical Physics (NCTP-39). Both the workshop and the conference were held from 28th - 31st July 2014 in Dakruco Hotel, Buon Ma Thuot, Dak Lak, Vietnam. The NCTP-39 and the IWTCP-2 were organized under the support of the Vietnamese Theoretical Physics Society, with a motivation to foster scientific exchanges between the theoretical and computational physicists in Vietnam and worldwide, as well as to promote high-standard level of research and education activities for young physicists in the country. The IWTCP-2 was also an External Activity of the Asia Pacific Center for Theoretical Physics (APCTP). About 100 participants coming from nine countries participated in the workshop and the conference. At the IWTCP-2 workshop, we had 16 invited talks presented by international experts, together with eight oral and ten poster contributions. At the NCTP-39, three invited talks, 15 oral contributions and 39 posters were presented. We would like to thank all invited speakers, participants and sponsors for making the workshop and the conference successful. Trinh Xuan Hoang, Nguyen Anh Ky, Nguyen Tri Lan and Nguyen Ai Viet

The Charm of Theoretical Physics (1958-1993)

NASA Astrophysics Data System (ADS)

Maiani, Luciano; Bonolis, Luisa

2017-12-01

Personal recollections on theoretical particle physics in the years when the Standard Theory was formed. In the background, the remarkable development of Italian theoretical physics in the second part of the last century, with great personalities like Bruno Touschek, Raoul Gatto, Nicola Cabibbo and their schools.

Improving Treatment Response for Paediatric Anxiety Disorders: An Information-Processing Perspective.

PubMed

Ege, Sarah; Reinholdt-Dunne, Marie Louise

2016-12-01

Cognitive behavioural therapy (CBT) is considered the treatment of choice for paediatric anxiety disorders, yet there remains substantial room for improvement in treatment outcomes. This paper examines whether theory and research into the role of information-processing in the underlying psychopathology of paediatric anxiety disorders indicate possibilities for improving treatment response. Using a critical review of recent theoretical, empirical and academic literature, the paper examines the role of information-processing biases in paediatric anxiety disorders, the extent to which CBT targets information-processing biases, and possibilities for improving treatment response. The literature reviewed indicates a role for attentional and interpretational biases in anxious psychopathology. While there is theoretical grounding and limited empirical evidence to indicate that CBT ameliorates interpretational biases, evidence regarding the effects of CBT on attentional biases is mixed. Novel treatment methods including attention bias modification training, attention feedback awareness and control training, and mindfulness-based therapy may hold potential in targeting attentional biases, and thereby in improving treatment response. The integration of novel interventions into an existing evidence-based protocol is a complex issue and faces important challenges with regard to determining the optimal treatment package. Novel interventions targeting information-processing biases may hold potential in improving response to CBT for paediatric anxiety disorders. Many important questions remain to be answered.

A Grammar Library for Information Structure

ERIC Educational Resources Information Center

Song, Sanghoun

2014-01-01

This dissertation makes substantial contributions to both the theoretical and computational treatment of information structure, with an eye toward creating natural language processing applications such as multilingual machine translation systems. The aim of the present dissertation is to create a grammar library of information structure for the…

Solitonic Josephson-based meminductive systems

NASA Astrophysics Data System (ADS)

Guarcello, Claudio; Solinas, Paolo; di Ventra, Massimiliano; Giazotto, Francesco

2017-04-01

Memristors, memcapacitors, and meminductors represent an innovative generation of circuit elements whose properties depend on the state and history of the system. The hysteretic behavior of one of their constituent variables, is their distinctive fingerprint. This feature endows them with the ability to store and process information on the same physical location, a property that is expected to benefit many applications ranging from unconventional computing to adaptive electronics to robotics. Therefore, it is important to find appropriate memory elements that combine a wide range of memory states, long memory retention times, and protection against unavoidable noise. Although several physical systems belong to the general class of memelements, few of them combine these important physical features in a single component. Here, we demonstrate theoretically a superconducting memory based on solitonic long Josephson junctions. Moreover, since solitons are at the core of its operation, this system provides an intrinsic topological protection against external perturbations. We show that the Josephson critical current behaves hysteretically as an external magnetic field is properly swept. Accordingly, long Josephson junctions can be used as multi-state memories, with a controllable number of available states, and in other emerging areas such as memcomputing, i.e., computing directly in/by the memory.

Physical Chemistry of Reaction Dynamics in Ionic Liquids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Margulis, Claudio Javier

2016-10-31

The Margulis group BES funded research at the University of Iowa is part of a broader collaborative effort that includes the groups of Blank (U. Minnesota), Castner (Rutgers U.), Maroncelli (Penn. State U.) and Wishart (BNL). The goal of this group of PIs is to better understand from an experimental and a theoretical perspective different aspects of photo-initiated electron transfer processes in a set of different room-temperature ionic-liquid systems. The Margulis contribution is theoretical and computational. Details are presented in the attached documentation.

The hippocampus and exploration: dynamically evolving behavior and neural representations

PubMed Central

Johnson, Adam; Varberg, Zachary; Benhardus, James; Maahs, Anthony; Schrater, Paul

2012-01-01

We develop a normative statistical approach to exploratory behavior called information foraging. Information foraging highlights the specific processes that contribute to active, rather than passive, exploration and learning. We hypothesize that the hippocampus plays a critical role in active exploration through directed information foraging by supporting a set of processes that allow an individual to determine where to sample. By examining these processes, we show how information directed information foraging provides a formal theoretical explanation for the common hippocampal substrates of constructive memory, vicarious trial and error behavior, schema-based facilitation of memory performance, and memory consolidation. PMID:22848196

Transversal homoclinic orbits in a transiently chaotic neural network.

PubMed

Chen, Shyan-Shiou; Shih, Chih-Wen

2002-09-01

We study the existence of snap-back repellers, hence the existence of transversal homoclinic orbits in a discrete-time neural network. Chaotic behaviors for the network system in the sense of Li and Yorke or Marotto can then be concluded. The result is established by analyzing the structures of the system and allocating suitable parameters in constructing the fixed points and their pre-images for the system. The investigation provides a theoretical confirmation on the scenario of transient chaos for the system. All the parameter conditions for the theory can be examined numerically. The numerical ranges for the parameters which yield chaotic dynamics and convergent dynamics provide significant information in the annealing process in solving combinatorial optimization problems using this transiently chaotic neural network. (c) 2002 American Institute of Physics.

Encryption method based on pseudo random spatial light modulation for single-fibre data transmission

NASA Astrophysics Data System (ADS)

Kowalski, Marcin; Zyczkowski, Marek

2017-11-01

Optical cryptosystems can provide encryption and sometimes compression simultaneously. They are increasingly attractive for information securing especially for image encryption. Our studies shown that the optical cryptosystems can be used to encrypt optical data transmission. We propose and study a new method for securing fibre data communication. The paper presents a method for optical encryption of data transmitted with a single optical fibre. The encryption process relies on pseudo-random spatial light modulation, combination of two encryption keys and the Compressed Sensing framework. A linear combination of light pulses with pseudo-random patterns provides a required encryption performance. We propose an architecture to transmit the encrypted data through the optical fibre. The paper describes the method, presents the theoretical analysis, design of physical model and results of experiment.

Estimation of optimal hologram recording modes on photothermal materials

NASA Astrophysics Data System (ADS)

Dzhamankyzov, Nasipbek Kurmanalievich; Ismanov, Yusupzhan Khakimzhanovich; Zhumaliev, Kubanychbek Myrzabekovich; Alymkulov, Samsaly Amanovich

2018-01-01

A theoretical analysis of the hologram recording process on photothermal media to estimate the required laser radiation power for the information recording as the function of the spatial frequency and radiation exposure duration is considered. Results of the analysis showed that materials with a low thermal diffusivity are necessary to increase the recording density in these media and the recording should be performed with short pulses to minimize the thermal diffusion length. A solution for the heat conduction equation for photothermal materials heated by an interference laser field was found. The solution obtained allows one to determine the required value of the recording temperature for given spatial frequencies, depending on the thermal physical parameters of the medium and on the power and duration of the heating radiation.

Genetic information and ecosystem health: arguments for the application of chaos theory to identify boundary conditions for ecosystem management.

PubMed Central

Stomp, A M

1994-01-01

To meet the demands for goods and services of an exponentially growing human population, global ecosystems will come under increasing human management. The hallmark of successful ecosystem management will be long-term ecosystem stability. Ecosystems and the genetic information and processes which underlie interactions of organisms with the environment in populations and communities exhibit behaviors which have nonlinear characteristics. Nonlinear mathematical formulations describing deterministic chaos have been used successfully to model such systems in physics, chemistry, economics, physiology, and epidemiology. This approach can be extended to ecotoxicology and can be used to investigate how changes in genetic information determine the behavior of populations and communities. This article seeks to provide the arguments for such an approach and to give initial direction to the search for the boundary conditions within which lies ecosystem stability. The identification of a theoretical framework for ecotoxicology and the parameters which drive the underlying model is a critical component in the formulation of a prioritized research agenda and appropriate ecosystem management policy and regulation. PMID:7713038

Daughters and mothers exercising together (DAMET): a 12-week pilot project designed to improve physical self-perception and increase recreational physical activity.

PubMed

Ransdell, L B; Dratt, J; Kennedy, C; O'Neill, S; DeVoe, D

2001-01-01

This paper presents the results of a 12-week single-sex, family-based physical activity intervention grounded in Social Cognitive Theory. Mother/daughter pairs and triads (n = 20) attended physical activity and classroom sessions twice weekly. Physiological data (VO2peak, height, and weight), psychological data (physical self-perception profile subscale scores), information about physical activity participation (PAP, d x wk(-1)) and qualitative impressions (QI) of the program were collected pre- and post-intervention. PAP and QI were also collected 6-months after completing the intervention. Although no significant increases in physical activity were reported, significant improvements in perceived sport competence, physical condition, and strength and muscularity were reported over time. The social cognitive theory, as used to plan this physical activity intervention, offered a promising theoretical perspective for facilitating improved physical self-perception in adolescent girls and their mothers.

Information Processing: A Review of Implications of Johnstone's Model for Science Education

ERIC Educational Resources Information Center

St Clair-Thompson, Helen; Overton, Tina; Botton, Chris

2010-01-01

The current review is concerned with an information processing model used in science education. The purpose is to summarise the current theoretical understanding, in published research, of a number of factors that are known to influence learning and achievement. These include field independence, working memory, long-term memory, and the use of…

Hop limited epidemic-like information spreading in mobile social networks with selfish nodes

NASA Astrophysics Data System (ADS)

Wu, Yahui; Deng, Su; Huang, Hongbin

2013-07-01

Similar to epidemics, information can be transmitted directly among users in mobile social networks. Different from epidemics, we can control the spreading process by adjusting the corresponding parameters (e.g., hop count) directly. This paper proposes a theoretical model to evaluate the performance of an epidemic-like spreading algorithm, in which the maximal hop count of the information is limited. In addition, our model can be used to evaluate the impact of users’ selfish behavior. Simulations show the accuracy of our theoretical model. Numerical results show that the information hop count can have an important impact. In addition, the impact of selfish behavior is related to the information hop count.

Fragments of Science: Festschrift for Mendel Sachs

NASA Astrophysics Data System (ADS)

Ram, Michael

1999-11-01

The Table of Contents for the full book PDF is as follows: * Preface * Sketches at a Symposium * For Mendel Sachs * The Constancy of an Angular Point of View * Information-Theoretic Logic and Transformation-Theoretic Logic * The Invention of the Transistor and the Realization of the Hole * Mach's Principle, Newtonian Gravitation, Absolute Space, and Einstein * The Sun, Our Variable Star * The Inconstant Sun: Symbiosis of Time Variations of Sunspots, Atmospheric Radiocarbon, Aurorae, and Tree Ring Growth * Other Worlds * Super-Classical Quantum Mechanics * A Probabilistic Approach to the Phase Problem of X-Ray Crystallography * A Nonlinear Twist on Inertia Gives Unified Electroweak Gravitation * Neutrino Oscillations * On an Incompleteness in the General-Relativistic Description of Gravitation * All Truth is One * Ideas of Physics: Correspondence between Colleagues * The Influence of the Physics and Philosophy of Einstein's Relativity on My Attitudes in Science: An Autobiography

Facilitating Behavior Change with Low-Literacy Patient Education Materials

ERIC Educational Resources Information Center

Seligman, Hilary K.; Wallace, Andrea S.; DeWalt, Darren A.; Schillinger, Dean; Arnold, Connie L.; Shilliday, Betsy Bryant; Delgadillo, Adriana; Bengal, Nikki; Davis, Terry C.

2007-01-01

Objective: To describe a process for developing low-literacy health education materials that increase knowledge and activate patients toward healthier behaviors. Methods: We developed a theoretically informed process for developing educational materials. This process included convening a multidisciplinary creative team, soliciting stakeholder…

IMMAN: free software for information theory-based chemometric analysis.

PubMed

Urias, Ricardo W Pino; Barigye, Stephen J; Marrero-Ponce, Yovani; García-Jacas, César R; Valdes-Martiní, José R; Perez-Gimenez, Facundo

2015-05-01

The features and theoretical background of a new and free computational program for chemometric analysis denominated IMMAN (acronym for Information theory-based CheMoMetrics ANalysis) are presented. This is multi-platform software developed in the Java programming language, designed with a remarkably user-friendly graphical interface for the computation of a collection of information-theoretic functions adapted for rank-based unsupervised and supervised feature selection tasks. A total of 20 feature selection parameters are presented, with the unsupervised and supervised frameworks represented by 10 approaches in each case. Several information-theoretic parameters traditionally used as molecular descriptors (MDs) are adapted for use as unsupervised rank-based feature selection methods. On the other hand, a generalization scheme for the previously defined differential Shannon's entropy is discussed, as well as the introduction of Jeffreys information measure for supervised feature selection. Moreover, well-known information-theoretic feature selection parameters, such as information gain, gain ratio, and symmetrical uncertainty are incorporated to the IMMAN software ( http://mobiosd-hub.com/imman-soft/ ), following an equal-interval discretization approach. IMMAN offers data pre-processing functionalities, such as missing values processing, dataset partitioning, and browsing. Moreover, single parameter or ensemble (multi-criteria) ranking options are provided. Consequently, this software is suitable for tasks like dimensionality reduction, feature ranking, as well as comparative diversity analysis of data matrices. Simple examples of applications performed with this program are presented. A comparative study between IMMAN and WEKA feature selection tools using the Arcene dataset was performed, demonstrating similar behavior. In addition, it is revealed that the use of IMMAN unsupervised feature selection methods improves the performance of both IMMAN and WEKA supervised algorithms. Graphic representation for Shannon's distribution of MD calculating software.

Information-theoretic signatures of biodiversity in the barcoding gene.

PubMed

Barbosa, Valmir C

2018-08-14

Analyzing the information content of DNA, though holding the promise to help quantify how the processes of evolution have led to information gain throughout the ages, has remained an elusive goal. Paradoxically, one of the main reasons for this has been precisely the great diversity of life on the planet: if on the one hand this diversity is a rich source of data for information-content analysis, on the other hand there is so much variation as to make the task unmanageable. During the past decade or so, however, succinct fragments of the COI mitochondrial gene, which is present in all animal phyla and in a few others, have been shown to be useful for species identification through DNA barcoding. A few million such fragments are now publicly available through the BOLD systems initiative, thus providing an unprecedented opportunity for relatively comprehensive information-theoretic analyses of DNA to be attempted. Here we show how a generalized form of total correlation can yield distinctive information-theoretic descriptors of the phyla represented in those fragments. In order to illustrate the potential of this analysis to provide new insight into the evolution of species, we performed principal component analysis on standardized versions of the said descriptors for 23 phyla. Surprisingly, we found that, though based solely on the species represented in the data, the first principal component correlates strongly with the natural logarithm of the number of all known living species for those phyla. The new descriptors thus constitute clear information-theoretic signatures of the processes whereby evolution has given rise to current biodiversity, which suggests their potential usefulness in further related studies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Solar Physics - Plasma Physics Workshop

NASA Technical Reports Server (NTRS)

Baum, P. J.; Beckers, J. M.; Newman, C. E.; Priest, E. R.; Rosenberg, H.; Smith, D. F.; Sturrock, P. A.; Wentzel, D. G.

1974-01-01

A summary of the proceedings of a conference whose purpose was to explore plasma physics problems which arise in the study of solar physics is provided. Sessions were concerned with specific questions including the following: (1) whether the solar plasma is thermal or non-themal; (2) what spectroscopic data is required; (3) what types of magnetic field structures exist; (4) whether magnetohydrodynamic instabilities occur; (5) whether resistive or non-magnetohydrodynamic instabilities occur; (6) what mechanisms of particle acceleration have been proposed; and (7) what information is available concerning shock waves. Very few questions were answered categorically but, for each question, there was discussion concerning the observational evidence, theoretical analyses, and existing or potential laboratory and numerical experiments.

Provision of wear resistance and fatigue strength of surfaces during electroerosive processing

NASA Astrophysics Data System (ADS)

Fedonin, O. N.; Syanov, S. Yu; Papikyan, A. M.

2018-03-01

This article is a generalization of the results of theoretical studies of the effect of erosion control regimes on the operational properties of mold-forming parts of molds. The main problem is the provision of wear resistance and fatigue strength in the electroerosion processing of these types of products. The analysis showed that the fatigue strength is affected by the processing regimes and the coefficient after the erosion treatment. The index of wear resistance is determined both by the treatment modes and by the physical-mechanical properties of the billet materials. To ensure the operational performance of products, it is necessary to establish the physical picture of the processing of complex profile parts by finding the optimum eroding regime.

Cognitive Overhead in Hypertext Learning Reexamined: Overcoming the Myths

ERIC Educational Resources Information Center

Zumbach, Joerg

2006-01-01

In hypertext learning, comparative research is mostly dedicated to differences in text-hypertext information retrieval and processing and to optimization of nonlinear information retrieval. Most of these investigations are conducted within the context of applied research. The theoretical background of information acquisition from linear and…

Study report on laser storage and retrieval of image data

NASA Technical Reports Server (NTRS)

Becker, C. H.

1976-01-01

The theoretical foundation is presented for a system of real-time nonphotographic and nonmagnetic digital laser storage and retrieval of image data. The system utilizes diffraction-limited laser focusing upon thin metal films, melting elementary holes in the metal films in laser focus. The metal films are encapsulated in rotating flexible mylar discs which act as the permanent storage carries. Equal sized holes encompass two dimensional digital ensembles of information bits which are time-sequentially (bit by bit) stored and retrieved. The bits possess the smallest possible size, defined by the Rayleigh criterion of coherent physical optics. Space and time invariant reflective read-out of laser discs with a small laser, provides access to the stored digital information. By eliminating photographic and magnetic data processing, which characterize the previous state of the art, photographic grain, diffusion, and gamma-distortion do not exist. Similarly, magnetic domain structures, magnetic gaps, and magnetic read-out are absent with a digital laser disc system.

Theoretical Mathematics

NASA Astrophysics Data System (ADS)

Stöltzner, Michael

Answering to the double-faced influence of string theory on mathematical practice and rigour, the mathematical physicists Arthur Jaffe and Frank Quinn have contemplated the idea that there exists a `theoretical' mathematics (alongside `theoretical' physics) whose basic structures and results still require independent corroboration by mathematical proof. In this paper, I shall take the Jaffe-Quinn debate mainly as a problem of mathematical ontology and analyse it against the backdrop of two philosophical views that are appreciative towards informal mathematical development and conjectural results: Lakatos's methodology of proofs and refutations and John von Neumann's opportunistic reading of Hilbert's axiomatic method. The comparison of both approaches shows that mitigating Lakatos's falsificationism makes his insights about mathematical quasi-ontology more relevant to 20th century mathematics in which new structures are introduced by axiomatisation and not necessarily motivated by informal ancestors. The final section discusses the consequences of string theorists' claim to finality for the theory's mathematical make-up. I argue that ontological reductionism as advocated by particle physicists and the quest for mathematically deeper axioms do not necessarily lead to identical results.

Social challenges when implementing information systems in everyday work in a nursing context.

PubMed

Nilsson, Lina; Eriksén, Sara; Borg, Christel

2014-09-01

Implementation of information systems in healthcare has become a lengthy process where healthcare staff (eg, nurses) are expected to put information into systems without getting the overall picture of the potential usefulness for their own work. The aim of this study was to explore social challenges when implementing information systems in everyday work in a nursing context. Moreover, this study aimed at putting perceived social challenges in a theoretical framework to address them more constructively when implementing information systems in healthcare. Influenced by institutional ethnography, the findings are based on interviews, observations, and written reflections. Power (changing the existing hierarchy, alienation), professional identity (calling on hold, expert becomes novice, changed routines), and encounter (ignorant introductions, preconceived notions) were categories (subcategories) presented in the findings. Social Cognitive Theory, Diffusion of Innovations, organizational culture, and dramaturgical analysis are proposed to set up a theoretical framework. If social challenges are not considered and addressed in the implementation process, it will be affected by nurses' solidarity to existing power structures and their own professional identity. Thus, implementation of information systems affects more aspects in the organization than might have been intended. These aspects need to be taken in to account in the implementation process.

Parent–Child Aggression Risk in Expectant Mothers and Fathers: A Multimethod Theoretical Approach

PubMed Central

Smith, Tamika L.; Silvia, Paul J.

2016-01-01

The current investigation evaluated whether cognitive processes characteristic of the Social Information Processing model predicted parent-child aggression (PCA) risk independent of personal vulnerabilities and resiliencies. This study utilized a multimethod approach, including analog tasks, with a diverse sample of 203 primiparous expectant mothers and 151 of their partners. Factors considered in this study included PCA approval attitudes, empathy, reactivity, negative child attributions, compliance expectations, and knowledge of non-physical discipline alternatives; additionally, vulnerabilities included psychopathology symptoms, domestic violence victimization, and substance use, whereas resiliencies included perceived social support, partner relationship satisfaction, and coping efficacy. For both mothers and fathers, findings supported the role of greater approval of PCA attitudes, lower empathy, more overreactivity, more negative attributions, and higher compliance expectations in relation to elevated risk of PCA. Moreover, personal vulnerabilities and resiliencies related to PCA risk for mothers; however, fathers and mothers differed on the nature of these relationships with respect to vulnerabilities as well as aspects of empathy and PCA approval attitudes. Findings provide evidence for commonalities in many of the factors investigated between mothers and fathers with some notable distinctions. Results are discussed in terms of how findings could inform prevention programs. PMID:28082826

Geometric reduction of dynamical nonlocality in nanoscale quantum circuits.

PubMed

Strambini, E; Makarenko, K S; Abulizi, G; de Jong, M P; van der Wiel, W G

2016-01-06

Nonlocality is a key feature discriminating quantum and classical physics. Quantum-interference phenomena, such as Young's double slit experiment, are one of the clearest manifestations of nonlocality, recently addressed as dynamical to specify its origin in the quantum equations of motion. It is well known that loss of dynamical nonlocality can occur due to (partial) collapse of the wavefunction due to a measurement, such as which-path detection. However, alternative mechanisms affecting dynamical nonlocality have hardly been considered, although of crucial importance in many schemes for quantum information processing. Here, we present a fundamentally different pathway of losing dynamical nonlocality, demonstrating that the detailed geometry of the detection scheme is crucial to preserve nonlocality. By means of a solid-state quantum-interference experiment we quantify this effect in a diffusive system. We show that interference is not only affected by decoherence, but also by a loss of dynamical nonlocality based on a local reduction of the number of quantum conduction channels of the interferometer. With our measurements and theoretical model we demonstrate that this mechanism is an intrinsic property of quantum dynamics. Understanding the geometrical constraints protecting nonlocality is crucial when designing quantum networks for quantum information processing.

Information theoretical assessment of image gathering and coding for digital restoration

NASA Technical Reports Server (NTRS)

Huck, Friedrich O.; John, Sarah; Reichenbach, Stephen E.

1990-01-01

The process of image-gathering, coding, and restoration is presently treated in its entirety rather than as a catenation of isolated tasks, on the basis of the relationship between the spectral information density of a transmitted signal and the restorability of images from the signal. This 'information-theoretic' assessment accounts for the information density and efficiency of the acquired signal as a function of the image-gathering system's design and radiance-field statistics, as well as for the information efficiency and data compression that are obtainable through the combination of image gathering with coding to reduce signal redundancy. It is found that high information efficiency is achievable only through minimization of image-gathering degradation as well as signal redundancy.

Dynamic Motivational Processing of Antimarijuana Messages: Coactivation Begets Attention

ERIC Educational Resources Information Center

Wang, Zheng; Solloway, Tyler; Tchernev, John M.; Barker, Bethany

2012-01-01

In the theoretical framework of dynamic motivational activation, this study reveals the dynamics of antimarijuana public service announcement (PSA) processing, especially the processing of co-occurring positive and negative content. It specifies the important role of endogenous feedback dynamics of the information processing system and teases them…

The relation between students' communicative moves during laboratory work in physics and outcomes of their actions

NASA Astrophysics Data System (ADS)

Andersson, J.; Enghag, M.

2017-01-01

In this case study, we explore students' communication during practical work in physics at an upper secondary school in Sweden from a sociocultural perspective. We investigate the relation between the interaction and content of students' communication and outcomes of their actions, with the purpose of finding new knowledge for informing teachers in their choice of instruction. We make discourse analysis of how students interact but also of what students are discussing in terms of underlying content at a linguistic and cognitive level. Twenty students divided into five groups were video recorded while performing four practical tasks at different stations during laboratory work about motion. An analytical framework was developed and applied for one group to three parts of the transcripts in which three different talk-types occurred. Discursive, content, action and purposive moves in the process were identified for each talk-type at both linguistic and cognitive levels. These moves represent information concerning what the teacher actually assigns students to do, and how students make meaning of the activities. Through these different communicative moves, students experience how laboratory work can enhance their competence to collaborate in a scientific environment with complex practical and theoretical questions to solve quickly. Implications of the findings are discussed.

CBT Theory and Its Application: A School Phobic Kindergarten Case.

ERIC Educational Resources Information Center

Sigmon, Scott B.

Cognitive behavioral psychology is a new theoretical orientation and when applied in treatment it is known as cognitive behavior therapy (CBT). Theoretically CBT seeks primarily to change cognitions to alter behaviors and to modify cognitions to affect emotions. In general CBT is considered to be an information processing psychology because it…

Subjective Age Bias: A Motivational and Information Processing Approach

ERIC Educational Resources Information Center

Teuscher, Ursina

2009-01-01

There is broad empirical evidence, but still a lack of theoretical explanations, for the phenomenon that most older people feel considerably younger than their real age. In this article, a measurement model of subjective age was assessed, and two independent theoretical approaches are proposed: (1) a motivational approach assuming that the age…

The definitions of information and meaning two possible boundaries between physics and biology.

PubMed

Barbieri, Marcello

2004-01-01

The standard approach to the definition of the physical quantities has not produced satisfactory results with the concepts of information and meaning. In the case of information we have at least two unrelated definitions, while in the case of meaning we have no definition at all. Here it is shown that both information and meaning can be defined by operative procedures, but it is also pointed out that we need to recognize them as a new type of natural entities. They are not quantities (neither fundamental nor derived) because they cannot be measured, and they are not qualities because are not subjective features. Here it is proposed to call them nominable entities, i.e., entities which can be specified only by naming their components in their natural order. If the genetic code is not a linguistic metaphor but a reality, we must conclude that information and meaning are real natural entities, and now we must also conclude that they are not equivalent to the quantities and qualities of our present theoretical framework. This gives us two options. One is to extend the definition of physics and say that the list of its fundamental entities must include information and meaning. The other is to say that physics is the science of quantities only, and in this case information and meaning become the exclusive province of biology. The boundary between physics and biology, in short, is a matter of convention, but the existence of information and meaning is not. We can decide to study them in the framework of an extended physics or in a purely biological framework, but we cannot avoid studying them for what they are, i.e., as fundamental components of the fabric of Nature.

Becoming a Physicist: How Identities and Practices Shape Physics Trajectories

NASA Astrophysics Data System (ADS)

Quan, Gina M.

This dissertation studies the relationships and processes which shape students' participation within the discipline of physics. Studying this early disciplinary participation gives insight to how students are supported in or pushed out of physics, which is an important step in cultivating a diverse set of physics students. This research occurs within two learning environments that we co-developed: a physics camp for high school girls and a seminar for undergraduate physics majors to get started in physics research. Using situated learning theory, we conceptualized physics learning to be intertwined with participation in physics practices and identity development. This theoretical perspective draws our attention to relationships between students and the physics community. Specifically, we study how students come to engage in the practices of the community and who they are within the physics community. We find that students' interactions with faculty and peers impact the extent to which students engage in authentic physics practices. These interactions also impact the extent to which students develop identities as physicists. We present implications of these findings for the design of physics learning spaces. Understanding this process of how students become members of the physics community will provide valuable insights into fostering a diverse set of successful trajectories in physics.

Investigating Addiction in the Changing Universe

PubMed Central

Dastoury, Mojgan; Aminaee, Tayebe; Ghaumi, Raheleh

2014-01-01

The process of globalization as the most significant characteristic of modern era is facilitated by several factors including Information Technology, the industry of production and distribution of information, the flow of goods, services, human beings, capitals, information and etc. This phenomenon, along with the complex and various identities and life styles created by the national and transnational determinants, has widely changed the nature of social phenomena, including addition. The present study aims to investigate the contribution of sociological studies in the field of addiction during 2001 to 2011 in Iran. This is done through performing content analysis on 41 peer reviewed papers. The selected samples were surveyed and compared according to theoretical frameworks and the social groups under study. The results showed that the analyzed papers extensively overlooked the process of contemporary social changes in Iran which could be caused either by the theoretical basis of the studies or the social groups under study. Following the theoretical views of previous decades, these papers largely considered addiction as a type of social deviation and misbehavior related to the men living in urban areas. PMID:25363096

Statistical physics of vaccination

NASA Astrophysics Data System (ADS)

Wang, Zhen; Bauch, Chris T.; Bhattacharyya, Samit; d'Onofrio, Alberto; Manfredi, Piero; Perc, Matjaž; Perra, Nicola; Salathé, Marcel; Zhao, Dawei

2016-12-01

Historically, infectious diseases caused considerable damage to human societies, and they continue to do so today. To help reduce their impact, mathematical models of disease transmission have been studied to help understand disease dynamics and inform prevention strategies. Vaccination-one of the most important preventive measures of modern times-is of great interest both theoretically and empirically. And in contrast to traditional approaches, recent research increasingly explores the pivotal implications of individual behavior and heterogeneous contact patterns in populations. Our report reviews the developmental arc of theoretical epidemiology with emphasis on vaccination, as it led from classical models assuming homogeneously mixing (mean-field) populations and ignoring human behavior, to recent models that account for behavioral feedback and/or population spatial/social structure. Many of the methods used originated in statistical physics, such as lattice and network models, and their associated analytical frameworks. Similarly, the feedback loop between vaccinating behavior and disease propagation forms a coupled nonlinear system with analogs in physics. We also review the new paradigm of digital epidemiology, wherein sources of digital data such as online social media are mined for high-resolution information on epidemiologically relevant individual behavior. Armed with the tools and concepts of statistical physics, and further assisted by new sources of digital data, models that capture nonlinear interactions between behavior and disease dynamics offer a novel way of modeling real-world phenomena, and can help improve health outcomes. We conclude the review by discussing open problems in the field and promising directions for future research.

Statistics-related and reliability-physics-related failure processes in electronics devices and products

NASA Astrophysics Data System (ADS)

Suhir, E.

2014-05-01

The well known and widely used experimental reliability "passport" of a mass manufactured electronic or a photonic product — the bathtub curve — reflects the combined contribution of the statistics-related and reliability-physics (physics-of-failure)-related processes. When time progresses, the first process results in a decreasing failure rate, while the second process associated with the material aging and degradation leads to an increased failure rate. An attempt has been made in this analysis to assess the level of the reliability physics-related aging process from the available bathtub curve (diagram). It is assumed that the products of interest underwent the burn-in testing and therefore the obtained bathtub curve does not contain the infant mortality portion. It has been also assumed that the two random processes in question are statistically independent, and that the failure rate of the physical process can be obtained by deducting the theoretically assessed statistical failure rate from the bathtub curve ordinates. In the carried out numerical example, the Raleigh distribution for the statistical failure rate was used, for the sake of a relatively simple illustration. The developed methodology can be used in reliability physics evaluations, when there is a need to better understand the roles of the statistics-related and reliability-physics-related irreversible random processes in reliability evaluations. The future work should include investigations on how powerful and flexible methods and approaches of the statistical mechanics can be effectively employed, in addition to reliability physics techniques, to model the operational reliability of electronic and photonic products.

Recurrence plots of discrete-time Gaussian stochastic processes

NASA Astrophysics Data System (ADS)

Ramdani, Sofiane; Bouchara, Frédéric; Lagarde, Julien; Lesne, Annick

2016-09-01

We investigate the statistical properties of recurrence plots (RPs) of data generated by discrete-time stationary Gaussian random processes. We analytically derive the theoretical values of the probabilities of occurrence of recurrence points and consecutive recurrence points forming diagonals in the RP, with an embedding dimension equal to 1. These results allow us to obtain theoretical values of three measures: (i) the recurrence rate (REC) (ii) the percent determinism (DET) and (iii) RP-based estimation of the ε-entropy κ(ε) in the sense of correlation entropy. We apply these results to two Gaussian processes, namely first order autoregressive processes and fractional Gaussian noise. For these processes, we simulate a number of realizations and compare the RP-based estimations of the three selected measures to their theoretical values. These comparisons provide useful information on the quality of the estimations, such as the minimum required data length and threshold radius used to construct the RP.

Total Quality Management in a Knowledge Management Perspective.

ERIC Educational Resources Information Center

Johannsen, Carl Gustav

2000-01-01

Presents theoretical considerations on both similarities and differences between information management and knowledge management and presents a conceptual model of basic knowledge management processes. Discusses total quality management and quality control in the context of information management. (Author/LRW)

Designing quantum information processing via structural physical approximation.

PubMed

Bae, Joonwoo

2017-10-01

In quantum information processing it may be possible to have efficient computation and secure communication beyond the limitations of classical systems. In a fundamental point of view, however, evolution of quantum systems by the laws of quantum mechanics is more restrictive than classical systems, identified to a specific form of dynamics, that is, unitary transformations and, consequently, positive and completely positive maps to subsystems. This also characterizes classes of disallowed transformations on quantum systems, among which positive but not completely maps are of particular interest as they characterize entangled states, a general resource in quantum information processing. Structural physical approximation offers a systematic way of approximating those non-physical maps, positive but not completely positive maps, with quantum channels. Since it has been proposed as a method of detecting entangled states, it has stimulated fundamental problems on classifications of positive maps and the structure of Hermitian operators and quantum states, as well as on quantum measurement such as quantum design in quantum information theory. It has developed efficient and feasible methods of directly detecting entangled states in practice, for which proof-of-principle experimental demonstrations have also been performed with photonic qubit states. Here, we present a comprehensive review on quantum information processing with structural physical approximations and the related progress. The review mainly focuses on properties of structural physical approximations and their applications toward practical information applications.

Designing quantum information processing via structural physical approximation

NASA Astrophysics Data System (ADS)

Bae, Joonwoo

2017-10-01

In quantum information processing it may be possible to have efficient computation and secure communication beyond the limitations of classical systems. In a fundamental point of view, however, evolution of quantum systems by the laws of quantum mechanics is more restrictive than classical systems, identified to a specific form of dynamics, that is, unitary transformations and, consequently, positive and completely positive maps to subsystems. This also characterizes classes of disallowed transformations on quantum systems, among which positive but not completely maps are of particular interest as they characterize entangled states, a general resource in quantum information processing. Structural physical approximation offers a systematic way of approximating those non-physical maps, positive but not completely positive maps, with quantum channels. Since it has been proposed as a method of detecting entangled states, it has stimulated fundamental problems on classifications of positive maps and the structure of Hermitian operators and quantum states, as well as on quantum measurement such as quantum design in quantum information theory. It has developed efficient and feasible methods of directly detecting entangled states in practice, for which proof-of-principle experimental demonstrations have also been performed with photonic qubit states. Here, we present a comprehensive review on quantum information processing with structural physical approximations and the related progress. The review mainly focuses on properties of structural physical approximations and their applications toward practical information applications.

Quantum Computation

NASA Astrophysics Data System (ADS)

Aharonov, Dorit

In the last few years, theoretical study of quantum systems serving as computational devices has achieved tremendous progress. We now have strong theoretical evidence that quantum computers, if built, might be used as a dramatically powerful computational tool, capable of performing tasks which seem intractable for classical computers. This review is about to tell the story of theoretical quantum computation. I l out the developing topic of experimental realizations of the model, and neglected other closely related topics which are quantum information and quantum communication. As a result of narrowing the scope of this paper, I hope it has gained the benefit of being an almost self contained introduction to the exciting field of quantum computation. The review begins with background on theoretical computer science, Turing machines and Boolean circuits. In light of these models, I define quantum computers, and discuss the issue of universal quantum gates. Quantum algorithms, including Shor's factorization algorithm and Grover's algorithm for searching databases, are explained. I will devote much attention to understanding what the origins of the quantum computational power are, and what the limits of this power are. Finally, I describe the recent theoretical results which show that quantum computers maintain their complexity power even in the presence of noise, inaccuracies and finite precision. This question cannot be separated from that of quantum complexity because any realistic model will inevitably be subjected to such inaccuracies. I tried to put all results in their context, asking what the implications to other issues in computer science and physics are. In the end of this review, I make these connections explicit by discussing the possible implications of quantum computation on fundamental physical questions such as the transition from quantum to classical physics.

Modeling the dynamics of multipartite quantum systems created departing from two-level systems using general local and non-local interactions

NASA Astrophysics Data System (ADS)

Delgado, Francisco

2017-12-01

Quantum information is an emergent area merging physics, mathematics, computer science and engineering. To reach its technological goals, it is requiring adequate approaches to understand how to combine physical restrictions, computational approaches and technological requirements to get functional universal quantum information processing. This work presents the modeling and the analysis of certain general type of Hamiltonian representing several physical systems used in quantum information and establishing a dynamics reduction in a natural grammar for bipartite processing based on entangled states.

Culturally Relevant Physical Education in Urban Schools: Reflecting Cultural Knowledge

ERIC Educational Resources Information Center

Flory, Sara B.; McCaughtry, Nate

2011-01-01

Using a three-part theoretical framework, the cultural relevance cycle--which consists of (a) knowing community dynamics, (b) knowing how community dynamics influence educational processes, and (c) implementing strategies that reflect cultural knowledge of the community--we examined teachers' and students' perspectives on culturally relevant…

Quantum Logic: Approach a Child's Environment from "Inside."

ERIC Educational Resources Information Center

Rhodes, William C.

1987-01-01

With the advent of quantum mechanics, physics has merged with psychology, and cognitive science has been revolutionized. Quantum logic supports the notion of influencing the environment by increasing the child's capacity for cognitive processing. This special educational approach is theoretically more effective than social and political…

Theoretical physics implications of gravitational wave observation with future detectors

NASA Astrophysics Data System (ADS)

Chamberlain, Katie; Yunes, Nicolás

2017-10-01

Gravitational waves encode invaluable information about the nature of the relatively unexplored extreme gravity regime, where the gravitational interaction is strong, nonlinear and highly dynamical. Recent gravitational wave observations by advanced LIGO have provided the first glimpses into this regime, allowing for the extraction of new inferences on different aspects of theoretical physics. For example, these detections provide constraints on the mass of the graviton, Lorentz violation in the gravitational sector, the existence of large extra dimensions, the temporal variability of Newton's gravitational constant, and modified dispersion relations of gravitational waves. Many of these constraints, however, are not yet competitive with constraints obtained, for example, through Solar System observations or binary pulsar observations. In this paper, we study the degree to which theoretical physics inferences drawn from gravitational wave observations will strengthen with detections from future detectors. We consider future ground-based detectors, such as the LIGO-class expansions A + , Voyager, Cosmic Explorer and the Einstein Telescope, as well as space-based detectors, such as various configurations of eLISA and the recently proposed LISA mission. We find that space-based detectors will place constraints on general relativity up to 12 orders of magnitude more stringently than current aLIGO bounds, but these space-based constraints are comparable to those obtained with the ground-based Cosmic Explorer or the Einstein Telescope (A + and Voyager only lead to modest improvements in constraints). We also generically find that improvements in the instrument sensitivity band at low frequencies lead to large improvements in certain classes of constraints, while sensitivity improvements at high frequencies lead to more modest gains. These results strengthen the case for the development of future detectors, while providing additional information that could be useful in future design decisions.

The physics of flocking: Correlation as a compass from experiments to theory

NASA Astrophysics Data System (ADS)

Cavagna, Andrea; Giardina, Irene; Grigera, Tomás S.

2018-01-01

Collective behavior in biological systems is a complex topic, to say the least. It runs wildly across scales in both space and time, involving taxonomically vastly different organisms, from bacteria and cell clusters, to insect swarms and up to vertebrate groups. It entails concepts as diverse as coordination, emergence, interaction, information, cooperation, decision-making, and synchronization. Amid this jumble, however, we cannot help noting many similarities between collective behavior in biological systems and collective behavior in statistical physics, even though none of these organisms remotely looks like an Ising spin. Such similarities, though somewhat qualitative, are startling, and regard mostly the emergence of global dynamical patterns qualitatively different from individual behavior, and the development of system-level order from local interactions. It is therefore tempting to describe collective behavior in biology within the conceptual framework of statistical physics, in the hope to extend to this new fascinating field at least part of the great predictive power of theoretical physics. In this review we propose that the conceptual cornerstone of this ambitious program be that of correlation. To illustrate this idea we address the case of collective behavior in bird flocks. Two key threads emerge, as two sides of one single story: the presence of scale-free correlations and the dynamical mechanism of information transfer. We discuss first static correlations in starling flocks, in particular the experimental finding of their scale-free nature, the formulation of models that account for this fact using maximum entropy, and the relation of scale-free correlations to information transfer. This is followed by a dynamic treatment of information propagation (propagation of turns across a flock), starting with a discussion of experimental results and following with possible theoretical explanations of those, which require the addition of behavioral inertia to existing theories of flocking. We finish with the definition and analysis of space-time correlations and their relevance to the detection of inertial behavior in the absence of external perturbations.

Nonlinear theory of diffusive acceleration of particles by shock waves

NASA Astrophysics Data System (ADS)

Malkov, M. A.; Drury, L. O'C.

2001-04-01

Among the various acceleration mechanisms which have been suggested as responsible for the nonthermal particle spectra and associated radiation observed in many astrophysical and space physics environments, diffusive shock acceleration appears to be the most successful. We review the current theoretical understanding of this process, from the basic ideas of how a shock energizes a few reactionless particles to the advanced nonlinear approaches treating the shock and accelerated particles as a symbiotic self-organizing system. By means of direct solution of the nonlinear problem we set the limit to the test-particle approximation and demonstrate the fundamental role of nonlinearity in shocks of astrophysical size and lifetime. We study the bifurcation of this system, proceeding from the hydrodynamic to kinetic description under a realistic condition of Bohm diffusivity. We emphasize the importance of collective plasma phenomena for the global flow structure and acceleration efficiency by considering the injection process, an initial stage of acceleration and, the related aspects of the physics of collisionless shocks. We calculate the injection rate for different shock parameters and different species. This, together with differential acceleration resulting from nonlinear large-scale modification, determines the chemical composition of accelerated particles. The review concentrates on theoretical and analytical aspects but our strategic goal is to link the fundamental theoretical ideas with the rapidly growing wealth of observational data.

Evolutionary preferences for physical formidability in leaders.

PubMed

Murray, Gregg R

2014-01-01

This research uses evolutionary theory to evaluate followers' preferences for physically formidable leaders and to identify conditions that stimulate those preferences. It employs a population-based survey experiment (N ≥ 760), which offers the advantages to internal validity of experiments and external validity of a highly heterogeneous sample drawn from a nationally representative subject pool. The theoretical argument proffered here is followers tend to prefer leaders with greater physical formidability because of evolutionary adaptations derived from humans' violent ancestral environment. In this environment, individuals who allied with and ultimately followed physically powerful partners were more likely to acquire and retain important resources necessary for survival and reproduction because the presence of the physically powerful partner cued opponents to avoid a challenge for the resources or risk a costly confrontation. This argument suggests and the results indicate that threatening (war) and nonthreatening (peace, cooperation, and control) stimuli differentially motivate preferences for physically formidable leaders. In particular, the findings suggest threatening conditions lead to preferences for leaders with more powerful physical attributes, both anthropometric (i.e., weight, height, and body mass index) and perceptual (i.e., attributes of being "physically imposing or intimidating" and "physically strong"). Overall, this research offers a theoretical framework from which to understand this otherwise seemingly irrational phenomenon. Further, it advances the emerging but long-neglected investigation of biological effects on political behavior and has implications for a fundamental process in democratic society, leader selection.

Impact of phenomenological theory of turbulence on pragmatic approach to fluvial hydraulics

NASA Astrophysics Data System (ADS)

Ali, Sk Zeeshan; Dey, Subhasish

2018-04-01

The phenomenological theory of turbulence (PTT) remains a long-standing and fascinating theory in turbulence research. In this review article, we highlight the state-of-the-science of the impact of the PTT on the pragmatic approach to fluvial hydraulics, explored over recent decades, discussing the salient and the subtle roles that the turbulence plays in governing many physical processes. To acquire a theoretical explanation of this pragmatic approach necessitates an intuitive thought that can bring together the background mechanisms of all the physical processes under one law—a thought that is capable of finding their inextricable links with the turbulent energy spectrum. We begin here with emphasizing the spectral and the co-spectral origin of the well-recognized laws of the wall, the resistance equation, and the turbulence intensities by portraying the typical momentum transfer mechanism of eddies in a turbulent flow. Next, we focus on the scaling laws of key fluvial processes derived from the perspective of the PTT, enlightening their physical insight and ability to judge how far the so-called empirical formulas can be used with confidence. The PTT has been able to disclose the origin of several primeval empirical formulas that have been used over many years without having any theoretical clarification and confirmation. Finally, we make an effort to describe some unsolved issues to be resolved as a future scope of research.

Validity of a scale of neighbourhood informal social control relevant to pre-schoolers' physical activity: A cross-sectional study.

PubMed

Cerin, Ester; Suen, Yi Nam; Barnett, Anthony; Huang, Wendy Y J; Mellecker, Robin R

2017-12-01

Childhood physical activity (PA) is important for health across the lifespan. Time pre-schoolers spend outdoors, which has been associated with more PA, is likely influenced by parents' perception of neighbourhood informal social control relevant to pre-schoolers' PA, defined as the willingness of neighbours to intervene to ensure social order and a safe community environment for young children's active play. To advance measurement of this construct, we assessed factorial and construct validities of the PA-related neighbourhood informal social control scale for parents of pre-schoolers (PANISC-PP). In 2013-2014, Hong Kong primary caregivers (n=394) of 3-5 year-old children completed a socio-demographic questionnaire, the preliminary version of the PANISC-PP, and self-report measures of theoretical neighbourhood correlates of PA-related neighbourhood informal social control (perceived signs of physical and social disorder, community cohesion, perceived stranger danger, risk of unintentional injury and traffic safety). The fit of the data to an a priori measurement model of the PANISC-PP was examined using confirmatory factor analyses. As the a priori model showed inadequate fit to the data, the factor structure was re-specified based on theoretical considerations. The final measurement models of the PANISC-PP showed acceptable fit to the data and consisted of three correlated latent factors: "General informal supervision", "Civic engagement for the creation of a better neighbourhood environment" and "Educating and assisting neighbourhood children". The internal reliability of the subscales was good (Cronbach's α values 0.82-0.89). Generalised additive mixed models indicated that all subscales were positively associated with community cohesion and scores on the subscale "Educating and assisting neighbourhood children" were related in the expected direction to all indicators of traffic and personal safety, supporting construct validity of the PANISC-PP. This study suggests that the PANISC-PP is a reliable and valid instrument for assessing parents' perceived neighbourhood informal social control related to pre-schoolers' PA.

Pattern Formation and Complexity Emergence

NASA Astrophysics Data System (ADS)

Berezin, Alexander A.

2001-03-01

Success of nonlinear modelling of pattern formation and self-organization encourages speculations on informational and number theoretical foundations of complexity emergence. Pythagorean "unreasonable effectiveness of integers" in natural processes is perhaps extrapolatable even to universal emergence "out-of-nothing" (Leibniz, Wheeler). Because rational numbers (R = M/N) are everywhere dense on real axis, any digital string (hence any "book" from "Library of Babel" of J.L.Borges) is "recorded" infinitely many times in arbitrary many rationals. Furthermore, within any arbitrary small interval there are infinitely many Rs for which (either or both) integers (Ms and Ns) "carry" any given string of any given length. Because any iterational process (such as generation of fractal features of Mandelbrot Set) is arbitrary closely approximatable with rational numbers, the infinite pattern of integers expresses itself in generation of complexity of the world, as well as in emergence of the world itself. This "tunnelling" from Platonic World ("Platonia" of J.Barbour) to a real (physical) world is modern recast of Leibniz's motto ("for deriving all from nothing there suffices a single principle").

The Intuitive Physics of the Equilibrium of the Lever and of the Hydraulic Pressures: Implications for the Teaching of Elementary Physics

ERIC Educational Resources Information Center

Masin, Sergio Cesare; Crivellaro, Francesco; Varotto, Diego

2014-01-01

The research field of intuitive physics focuses on discrepancies between theoretical and intuitive physical knowledge. Consideration of these discrepancies can help in the teaching of elementary physics. However, evidence shows that theoretical and intuitive physical knowledge may also be congruent. Physics teaching could further benefit from…

PREFACE: Conference of Theoretical Physics and Nonlinear Phenomena (CTPNP) 2014: ''From Universe to String's Scale''

NASA Astrophysics Data System (ADS)

2014-10-01

Theoretical physics is the first step for the development of science and technology. For more than 100 years it has delivered new and sophisticated discoveries which have changed human views of their surroundings and universe. Theoretical physics has also revealed that the governing law in our universe is not deterministic, and it is undoubtedly the foundation of our modern civilization. Contrary to its importance, research in theoretical physics is not well advanced in some developing countries such as Indonesia. This workshop provides the formal meeting in Indonesia devoted to the field of theoretical physics and is organized to cover all subjects of theoretical physics as well as nonlinear phenomena in order to create a gathering place for the theorists in Indonesia and surrounding countries, to motivate young physicists to keep doing active researches in the field and to encourage constructive communication among the community members. Following the success of the tenth previous meetings in this conference series, the eleventh conference was held in Sebelas Maret University (UNS), Surakarta, Indonesia on 15 February 2014. In addition, the conference was proceeded by School of Advance Physics at Gadjah Mada University (UGM), Yogyakarta, on 16-17 February 2014. The conference is expected to provide distinguished experts and students from various research fields of theoretical physics and nonlinear phenomena in Indonesia as well as from other continents the opportunities to present their works and to enhance contacts among them. The introduction to the conference is continued in the pdf.

Promoting physical therapists' of research evidence to inform clinical practice: part 1--theoretical foundation, evidence, and description of the PEAK program.

PubMed

Tilson, Julie K; Mickan, Sharon

2014-06-25

There is a need for theoretically grounded and evidence-based interventions that enhance the use of research evidence in physical therapist practice. This paper and its companion paper introduce the Physical therapist-driven Education for Actionable Knowledge translation (PEAK) program, an educational program designed to promote physical therapists' integration of research evidence into clinical decision-making. The pedagogical foundations for the PEAK educational program include Albert Bandura's social cognitive theory and Malcolm Knowles's adult learning theory. Additionally, two complementary frameworks of knowledge translation, the Promoting Action on Research Implementation in Health Services (PARiHS) and Knowledge to Action (KTA) Cycle, were used to inform the organizational elements of the program. Finally, the program design was influenced by evidence from previous attempts to facilitate the use of research in practice at the individual and organizational levels. The 6-month PEAK program consisted of four consecutive and interdependent components. First, leadership support was secured and electronic resources were acquired and distributed to participants. Next, a two-day training workshop consisting of didactic and small group activities was conducted that addressed the five steps of evidence based practice. For five months following the workshop, participants worked in small groups to review and synthesize literature around a group-selected area of common clinical interest. Each group contributed to the generation of a "Best Practices List" - a list of locally generated, evidence-based, actionable behaviors relevant to the groups' clinical practice. Ultimately, participants agreed to implement the Best Practices List in their clinical practice. This, first of two companion papers, describes the underlying pedagogical theories, knowledge translation frameworks, and research evidence used to derive the PEAK program - an educational program designed to promote the use of research evidence to inform physical therapist practice. The four components of the program are described in detail. The companion paper reports the results of a mixed methods feasibility analysis of this complex educational intervention.

Information-Theoretic Approach May Shed a Light to a Better Understanding and Sustaining the Integrity of Ecological-Societal Systems under Changing Climate

NASA Astrophysics Data System (ADS)

Kim, J.

2016-12-01

Considering high levels of uncertainty, epistemological conflicts over facts and values, and a sense of urgency, normal paradigm-driven science will be insufficient to mobilize people and nation toward sustainability. The conceptual framework to bridge the societal system dynamics with that of natural ecosystems in which humanity operates remains deficient. The key to understanding their coevolution is to understand `self-organization.' Information-theoretic approach may shed a light to provide a potential framework which enables not only to bridge human and nature but also to generate useful knowledge for understanding and sustaining the integrity of ecological-societal systems. How can information theory help understand the interface between ecological systems and social systems? How to delineate self-organizing processes and ensure them to fulfil sustainability? How to evaluate the flow of information from data through models to decision-makers? These are the core questions posed by sustainability science in which visioneering (i.e., the engineering of vision) is an essential framework. Yet, visioneering has neither quantitative measure nor information theoretic framework to work with and teach. This presentation is an attempt to accommodate the framework of self-organizing hierarchical open systems with visioneering into a common information-theoretic framework. A case study is presented with the UN/FAO's communal vision of climate-smart agriculture (CSA) which pursues a trilemma of efficiency, mitigation, and resilience. Challenges of delineating and facilitating self-organizing systems are discussed using transdisciplinary toold such as complex systems thinking, dynamic process network analysis and multi-agent systems modeling. Acknowledgments: This study was supported by the Korea Meteorological Administration Research and Development Program under Grant KMA-2012-0001-A (WISE project).

Theorizing and Researching Levels of Processing in Self-Regulated Learning

ERIC Educational Resources Information Center

Winne, Philip H.

2018-01-01

Background: Deep versus surface knowledge is widely discussed by educational practitioners. A corresponding construct, levels of processing, has received extensive theoretical and empirical attention in learning science and psychology. In both arenas, lower levels of information and shallower levels of processing are predicted and generally…

PREFACE: 15th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT2013)

NASA Astrophysics Data System (ADS)

Wang, Jianxiong

2014-06-01

This volume of Journal of Physics: Conference Series is dedicated to scientific contributions presented at the 15th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2013) which took place on 16-21 May 2013 at the Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China. The workshop series brings together computer science researchers and practitioners, and researchers from particle physics and related fields to explore and confront the boundaries of computing and of automatic data analysis and theoretical calculation techniques. This year's edition of the workshop brought together over 120 participants from all over the world. 18 invited speakers presented key topics on the universe in computer, Computing in Earth Sciences, multivariate data analysis, automated computation in Quantum Field Theory as well as computing and data analysis challenges in many fields. Over 70 other talks and posters presented state-of-the-art developments in the areas of the workshop's three tracks: Computing Technologies, Data Analysis Algorithms and Tools, and Computational Techniques in Theoretical Physics. The round table discussions on open-source, knowledge sharing and scientific collaboration stimulate us to think over the issue in the respective areas. ACAT 2013 was generously sponsored by the Chinese Academy of Sciences (CAS), National Natural Science Foundation of China (NFSC), Brookhaven National Laboratory in the USA (BNL), Peking University (PKU), Theoretical Physics Cernter for Science facilities of CAS (TPCSF-CAS) and Sugon. We would like to thank all the participants for their scientific contributions and for the en- thusiastic participation in all its activities of the workshop. Further information on ACAT 2013 can be found at http://acat2013.ihep.ac.cn. Professor Jianxiong Wang Institute of High Energy Physics Chinese Academy of Science Details of committees and sponsors are available in the PDF

Landscape analysis: Theoretical considerations and practical needs

USGS Publications Warehouse

Godfrey, A.E.; Cleaves, E.T.

1991-01-01

Numerous systems of land classification have been proposed. Most have led directly to or have been driven by an author's philosophy of earth-forming processes. However, the practical need of classifying land for planning and management purposes requires that a system lead to predictions of the results of management activities. We propose a landscape classification system composed of 11 units, from realm (a continental mass) to feature (a splash impression). The classification concerns physical aspects rather than economic or social factors; and aims to merge land inventory with dynamic processes. Landscape units are organized using a hierarchical system so that information may be assembled and communicated at different levels of scale and abstraction. Our classification uses a geomorphic systems approach that emphasizes the geologic-geomorphic attributes of the units. Realm, major division, province, and section are formulated by subdividing large units into smaller ones. For the larger units we have followed Fenneman's delineations, which are well established in the North American literature. Areas and districts are aggregated into regions and regions into sections. Units smaller than areas have, in practice, been subdivided into zones and smaller units if required. We developed the theoretical framework embodied in this classification from practical applications aimed at land use planning and land management in Maryland (eastern Piedmont Province near Baltimore) and Utah (eastern Uinta Mountains). ?? 1991 Springer-Verlag New York Inc.

Channelling information flows from observation to decision; or how to increase certainty

NASA Astrophysics Data System (ADS)

Weijs, S. V.

2015-12-01

To make adequate decisions in an uncertain world, information needs to reach the decision problem, to enable overseeing the full consequences of each possible decision.On its way from the physical world to a decision problem, information is transferred through the physical processes that influence the sensor, then through processes that happen in the sensor, through wires or electromagnetic waves. For the last decade, most information becomes digitized at some point. From moment of digitization, information can in principle be transferred losslessly. Information about the physical world is often also stored, sometimes in compressed form, such as physical laws, concepts, or models of specific hydrological systems. It is important to note, however, that all information about a physical system eventually has to originate from observation (although inevitably coloured by some prior assumptions). This colouring makes the compression lossy, but is effectively the only way to make use of similarities in time and space that enable predictions while measuring only a a few macro-states of a complex hydrological system.Adding physical process knowledge to a hydrological model can thus be seen as a convenient way to transfer information from observations from a different time or place, to make predictions about another situation, assuming the same dynamics are at work.The key challenge to achieve more certainty in hydrological prediction can therefore be formulated as a challenge to tap and channel information flows from the environment. For tapping more information flows, new measurement techniques, large scale campaigns, historical data sets, and large sample hydrology and regionalization efforts can bring progress. For channelling the information flows with minimum loss, model calibration, and model formulation techniques should be critically investigated. Some experience from research in a Swiss high alpine catchment are used as an illustration.

Theoretical studies on sRNA-mediated regulation in bacteria

NASA Astrophysics Data System (ADS)

Chang, Xiao-Xue; Xu, Liu-Fang; Shi, Hua-Lin

2015-12-01

Small RNA(sRNA)-mediated post-transcriptional regulation differs from protein-mediated regulation. Through base-pairing, sRNA can regulate the target mRNA in a catalytic or stoichiometric manner. Some theoretical models were built for comparison of the protein-mediated and sRNA-mediated modes in the steady-state behaviors and noise properties. Many experiments demonstrated that a single sRNA can regulate several mRNAs, which causes crosstalk between the targets. Here, we focus on some models in which two target mRNAs are silenced by the same sRNA to discuss their crosstalk features. Additionally, the sequence-function relationship of sRNA and its role in the kinetic process of base-pairing have been highlighted in model building. Project supported by the National Basic Research Program of China (Grant No. 2013CB834100), the National Natural Science Foundation of China (Grant Nos. 11121403 and 11274320), the Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Grant No. Y4KF171CJ1), the National Natural Science Foundation for Young Scholar of China (Grant No. 11304115), and the China Postdoctoral Science Foundation (Grant No. 2013M541282).

Supporting the Virtual Soldier With a Physics-Based Software Architecture

DTIC Science & Technology

2005-06-01

simple approach taken here). Rather, this paper demonstrates how existing solution schemes can rapidly expand; it embraces all theoretical solution... bodyj . In (5) the superscript ’T’ accompanying a vector denotes the transposition of the vector. The constraint force and moment are defined as F C=Z1 a a...FE codes as there are meshes, and the requested MD code. This is described next. Exactly how the PM instantiated each physics process became an issue

Nucleation in Polymers and Soft Matter

NASA Astrophysics Data System (ADS)

Xu, Xiaofei; Ting, Christina L.; Kusaka, Isamu; Wang, Zhen-Gang

2014-04-01

Nucleation is a ubiquitous phenomenon in many physical, chemical, and biological processes. In this review, we describe recent progress on the theoretical study of nucleation in polymeric fluids and soft matter, including binary mixtures (polymer blends, polymers in poor solvents, compressible polymer-small molecule mixtures), block copolymer melts, and lipid membranes. We discuss the methodological development for studying nucleation as well as novel insights and new physics obtained in the study of the nucleation behavior in these systems.

Contingency theoretic methodology for agent-based web-oriented manufacturing systems

NASA Astrophysics Data System (ADS)

Durrett, John R.; Burnell, Lisa J.; Priest, John W.

2000-12-01

The development of distributed, agent-based, web-oriented, N-tier Information Systems (IS) must be supported by a design methodology capable of responding to the convergence of shifts in business process design, organizational structure, computing, and telecommunications infrastructures. We introduce a contingency theoretic model for the use of open, ubiquitous software infrastructure in the design of flexible organizational IS. Our basic premise is that developers should change in the way they view the software design process from a view toward the solution of a problem to one of the dynamic creation of teams of software components. We postulate that developing effective, efficient, flexible, component-based distributed software requires reconceptualizing the current development model. The basic concepts of distributed software design are merged with the environment-causes-structure relationship from contingency theory; the task-uncertainty of organizational- information-processing relationships from information processing theory; and the concept of inter-process dependencies from coordination theory. Software processes are considered as employees, groups of processes as software teams, and distributed systems as software organizations. Design techniques already used in the design of flexible business processes and well researched in the domain of the organizational sciences are presented. Guidelines that can be utilized in the creation of component-based distributed software will be discussed.

Long-run evolution of the global economy: 1. Physical basis

NASA Astrophysics Data System (ADS)

Garrett, Timothy J.

2014-04-01

Climate change is a two-way street during the Anthropocene: civilization depends upon a favorable climate at the same time that it modifies it. Yet studies that forecast economic growth employ fundamentally different equations and assumptions than those used to model Earth's physical, chemical, and biological processes. In the interest of establishing a common theoretical framework, this article treats humanity like any other physical process; that is, as an open, nonequilibrium thermodynamic system that sustains existing circulations and furthers its material growth through the consumption and dissipation of energy. The link of physical to economic quantities comes from a prior result that establishes a fixed relationship between rates of global energy consumption and a historical accumulation of global economic wealth. What follows are nonequilibrium prognostic expressions for how wealth, energy consumption, and the Gross World Product (GWP) grow with time. This paper shows that the key components that determine whether civilization "innovates" itself toward faster economic growth include energy reserve discovery, improvements to human and infrastructure longevity, and reductions in the amount of energy required to extract raw materials. Growth slows due to a combination of prior growth, energy reserve depletion, and a "fraying" of civilization networks due to natural disasters. Theoretical and numerical arguments suggest that when growth rates approach zero, civilization becomes fragile to such externalities as natural disasters, and the risk is for an accelerating collapse.

10 CFR 1017.28 - Processing on Automated Information Systems (AIS).

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Processing on Automated Information Systems (AIS). 1017.28... UNCLASSIFIED CONTROLLED NUCLEAR INFORMATION Physical Protection Requirements § 1017.28 Processing on Automated Information Systems (AIS). UCNI may be processed or produced on any AIS that complies with the guidance in OMB...

Process connectivity in a naturally prograding river delta

NASA Astrophysics Data System (ADS)

Sendrowski, Alicia; Passalacqua, Paola

2017-03-01

River deltas are lowland systems that can display high hydrological connectivity. This connectivity can be structural (morphological connections), functional (control of fluxes), and process connectivity (information flow from system drivers to sinks). In this work, we quantify hydrological process connectivity in Wax Lake Delta, coastal Louisiana, by analyzing couplings among external drivers (discharge, tides, and wind) and water levels recorded at five islands and one channel over summer 2014. We quantify process connections with information theory, a branch of mathematics concerned with the communication of information. We represent process connections as a network; variables serve as network nodes and couplings as network links describing the strength, direction, and time scale of information flow. Comparing process connections at long (105 days) and short (10 days) time scales, we show that tides exhibit daily synchronization with water level, with decreasing strength from downstream to upstream, and that tides transfer information as tides transition from spring to neap. Discharge synchronizes with water level and the time scale of its information transfer compares well to physical travel times through the system, computed with a hydrodynamic model. Information transfer and physical transport show similar spatial patterns, although information transfer time scales are larger than physical travel times. Wind events associated with water level setup lead to increased process connectivity with highly variable information transfer time scales. We discuss the information theory results in the context of the hydrologic behavior of the delta, the role of vegetation as a connector/disconnector on islands, and the applicability of process networks as tools for delta modeling results.

Several foundational and information theoretic implications of Bell’s theorem

NASA Astrophysics Data System (ADS)

Kar, Guruprasad; Banik, Manik

2016-08-01

In 1935, Albert Einstein and two colleagues, Boris Podolsky and Nathan Rosen (EPR) developed a thought experiment to demonstrate what they felt was a lack of completeness in quantum mechanics (QM). EPR also postulated the existence of more fundamental theory where physical reality of any system would be completely described by the variables/states of that fundamental theory. This variable is commonly called hidden variable and the theory is called hidden variable theory (HVT). In 1964, John Bell proposed an empirically verifiable criterion to test for the existence of these HVTs. He derived an inequality, which must be satisfied by any theory that fulfill the conditions of locality and reality. He also showed that QM, as it violates this inequality, is incompatible with any local-realistic theory. Later it has been shown that Bell’s inequality (BI) can be derived from different set of assumptions and it also find applications in useful information theoretic protocols. In this review, we will discuss various foundational as well as information theoretic implications of BI. We will also discuss about some restricted nonlocal feature of quantum nonlocality and elaborate the role of Uncertainty principle and Complementarity principle in explaining this feature.

Physical descriptions of the bacterial nucleoid at large scales, and their biological implications

NASA Astrophysics Data System (ADS)

Benza, Vincenzo G.; Bassetti, Bruno; Dorfman, Kevin D.; Scolari, Vittore F.; Bromek, Krystyna; Cicuta, Pietro; Cosentino Lagomarsino, Marco

2012-07-01

Recent experimental and theoretical approaches have attempted to quantify the physical organization (compaction and geometry) of the bacterial chromosome with its complement of proteins (the nucleoid). The genomic DNA exists in a complex and dynamic protein-rich state, which is highly organized at various length scales. This has implications for modulating (when not directly enabling) the core biological processes of replication, transcription and segregation. We overview the progress in this area, driven in the last few years by new scientific ideas and new interdisciplinary experimental techniques, ranging from high space- and time-resolution microscopy to high-throughput genomics employing sequencing to map different aspects of the nucleoid-related interactome. The aim of this review is to present the wide spectrum of experimental and theoretical findings coherently, from a physics viewpoint. In particular, we highlight the role that statistical and soft condensed matter physics play in describing this system of fundamental biological importance, specifically reviewing classic and more modern tools from the theory of polymers. We also discuss some attempts toward unifying interpretations of the current results, pointing to possible directions for future investigation.

Communication Network Integration and Group Uniformity in a Complex Organization.

ERIC Educational Resources Information Center

Danowski, James A.; Farace, Richard V.

This paper contains a discussion of the limitations of research on group processes in complex organizations and the manner in which a procedure for network analysis in on-going systems can reduce problems. The research literature on group uniformity processes and on theoretical models of these processes from an information processing perspective…

Evaluating the Stressors of Divorce: Theoretical and Pragmatic Concerns.

ERIC Educational Resources Information Center

Burrell, Nancy A.; And Others

A study tested a theoretical model using data from court-ordered sessions about the utility of divorce mediation. Subjects, 974 couples who had filed for divorce with potential child-custody disputes, were informed about the process of mediation as a means to settle their custody disputes rather than relying on the court system to resolve their…

Conceptualising paediatric health disparities: a metanarrative systematic review and unified conceptual framework.

PubMed

Ridgeway, Jennifer L; Wang, Zhen; Finney Rutten, Lila J; van Ryn, Michelle; Griffin, Joan M; Murad, M Hassan; Asiedu, Gladys B; Egginton, Jason S; Beebe, Timothy J

2017-08-04

There exists a paucity of work in the development and testing of theoretical models specific to childhood health disparities even though they have been linked to the prevalence of adult health disparities including high rates of chronic disease. We conducted a systematic review and thematic analysis of existing models of health disparities specific to children to inform development of a unified conceptual framework. We systematically reviewed articles reporting theoretical or explanatory models of disparities on a range of outcomes related to child health. We searched Ovid Medline In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus (database inception to 9 July 2015). A metanarrative approach guided the analysis process. A total of 48 studies presenting 48 models were included. This systematic review found multiple models but no consensus on one approach. However, we did discover a fair amount of overlap, such that the 48 models reviewed converged into the unified conceptual framework. The majority of models included factors in three domains: individual characteristics and behaviours (88%), healthcare providers and systems (63%), and environment/community (56%), . Only 38% of models included factors in the health and public policies domain. A disease-agnostic unified conceptual framework may inform integration of existing knowledge of child health disparities and guide future research. This multilevel framework can focus attention among clinical, basic and social science research on the relationships between policy, social factors, health systems and the physical environment that impact children's health outcomes. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Investigation of the Influence of Microgravity on Transport Mechanisms in a Virtual Spaceflight Chamber: A Ground Based Program

NASA Technical Reports Server (NTRS)

Trolinger, James D.; Rangel, Roger; Witherow, William; Rogers, Jan; Lal, Ravindra B.

1999-01-01

In January 1992, the IML-1 FES experiment produced a set of classic experimental data and a 40 hour holographic "movie" of an ensemble of spheres in a fluid in microgravity. Because the data are in the form of holograms, we can study the three-dimensional distribution of particles with unprecedented detail by a variety of methods and for a wide variety of interests. The possession of the holographic movie is tantamount to having a complex experiment in space while working in an easily accessible laboratory on earth. The movie contains a vast amount of useful data, including residual g, g-jitter, convection and transport data, and particle fluid interaction data. The information content in the movie is so great that we have scarcely begun to tap into the data that is actually available in the more than 1000 holograms, each containing as much as 1000 megabytes of information. This ground-based project is exploiting this data and the concept of holographic storage of spaceflight data to provide an understanding of the effects of microgravity in materials processing. This paper provides the foundation, objectives, and status of the ground based project. The primary objective of this project is to advance the understanding of microgravity effects on crystal growth, convection in materials processing in the space environment, and complex transport phenomena at low Reynolds numbers. This objective is being achieved both experimentally and theoretically. Experiments are making use of existing holographic data recorded during the IML- I spaceflight. A parallel theoretical effort is providing the models for understanding the particle fields and their physics in the microgravity environment.

Individual Differences in Boys' and Girls' Timing and Tempo of Puberty: Modeling Development with Nonlinear Growth Models

ERIC Educational Resources Information Center

Marceau, Kristine; Ram, Nilam; Houts, Renate M.; Grimm, Kevin J.; Susman, Elizabeth J.

2011-01-01

Pubertal development is a nonlinear process progressing from prepubescent beginnings through biological, physical, and psychological changes to full sexual maturity. To tether theoretical concepts of puberty with sophisticated longitudinal, analytical models capable of articulating pubertal development more accurately, we used nonlinear…

The Noticing of Physical Education Teachers: A Comparison of Groups with Different Expertise

ERIC Educational Resources Information Center

Reuker, Sabine

2017-01-01

Background: Teachers' important diagnostic abilities include noticing and interpreting students' behaviors and learning processes. By focusing on noticing, I refer to the theoretical framework of professional vision. Professional vision includes the ability to notice what is occurring in complex classroom situations (selective attention) and the…

Identifiability Of Systems With Modeling Errors

NASA Technical Reports Server (NTRS)

Hadaegh, Yadolah " fred" ; Bekey, George A.

1988-01-01

Advances in theory of modeling errors reported. Recent paper on errors in mathematical models of deterministic linear or weakly nonlinear systems. Extends theoretical work described in NPO-16661 and NPO-16785. Presents concrete way of accounting for difference in structure between mathematical model and physical process or system that it represents.

A framework for spatial and temporal analysis of hillslope-channel coupling in a dryland basin 2401

USDA-ARS?s Scientific Manuscript database

The long-term evolution of channel longitudinal profiles within drainage basins is partly determined by the relative balance of hillslope sediment supply to channels and the evacuation of channel sediment. However, the lack of theoretical understanding of the physical processes of hillslope-channel...

Quantum Information Theory of Measurement

NASA Astrophysics Data System (ADS)

Glick, Jennifer Ranae

Quantum measurement lies at the heart of quantum information processing and is one of the criteria for quantum computation. Despite its central role, there remains a need for a robust quantum information-theoretical description of measurement. In this work, I will quantify how information is processed in a quantum measurement by framing it in quantum information-theoretic terms. I will consider a diverse set of measurement scenarios, including weak and strong measurements, and parallel and consecutive measurements. In each case, I will perform a comprehensive analysis of the role of entanglement and entropy in the measurement process and track the flow of information through all subsystems. In particular, I will discuss how weak and strong measurements are fundamentally of the same nature and show that weak values can be computed exactly for certain measurements with an arbitrary interaction strength. In the context of the Bell-state quantum eraser, I will derive a trade-off between the coherence and "which-path" information of an entangled pair of photons and show that a quantum information-theoretic approach yields additional insights into the origins of complementarity. I will consider two types of quantum measurements: those that are made within a closed system where every part of the measurement device, the ancilla, remains under control (what I will call unamplified measurements), and those performed within an open system where some degrees of freedom are traced over (amplified measurements). For sequences of measurements of the same quantum system, I will show that information about the quantum state is encoded in the measurement chain and that some of this information is "lost" when the measurements are amplified-the ancillae become equivalent to a quantum Markov chain. Finally, using the coherent structure of unamplified measurements, I will outline a protocol for generating remote entanglement, an essential resource for quantum teleportation and quantum cryptographic tasks.

125 GeV Higgs decay with lepton flavor violation in the μνSSM

NASA Astrophysics Data System (ADS)

Zhang, Hai-Bin; Feng, Tai-Fu; Zhao, Shu-Min; Yan, Yu-Li; Sun, Fei

2017-04-01

Recently, the CMS and ATLAS collaborations have reported direct searches for the 125 GeV Higgs decay with lepton flavor violation, h → μτ. In this work, we analyze the signal of the lepton flavour violating (LFV) Higgs decay h → μτ in the μ from ν Supersymmetric Standard Model (μνSSM) with slepton flavor mixing. Simultaneously, we consider the constraints from the LFV decay τ → μγ, the muon anomalous magnetic dipole moment and the lightest Higgs mass around 125 GeV. Supported by Major Project of NNSFC (11535002) and NNSFC (11275036, 11647120), the Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Y5KF131CJ1), the Natural Science Foundation of Hebei province (A2013201277, A2016201010, A2016201069), Hebei Key Lab of Optic-Electronic Information and Materials, and Midwest Universities Comprehensive Strength Promotion Project

Quantum photonic network and physical layer security

NASA Astrophysics Data System (ADS)

Sasaki, Masahide; Endo, Hiroyuki; Fujiwara, Mikio; Kitamura, Mitsuo; Ito, Toshiyuki; Shimizu, Ryosuke; Toyoshima, Morio

2017-06-01

Quantum communication and quantum cryptography are expected to enhance the transmission rate and the security (confidentiality of data transmission), respectively. We study a new scheme which can potentially bridge an intermediate region covered by these two schemes, which is referred to as quantum photonic network. The basic framework is information theoretically secure communications in a free space optical (FSO) wiretap channel, in which an eavesdropper has physically limited access to the main channel between the legitimate sender and receiver. We first review a theoretical framework to quantify the optimal balance of the transmission efficiency and the security level under power constraint and at finite code length. We then present experimental results on channel characterization based on 10 MHz on-off keying transmission in a 7.8 km terrestrial FSO wiretap channel. This article is part of the themed issue 'Quantum technology for the 21st century'.

Quantum photonic network and physical layer security.

PubMed

Sasaki, Masahide; Endo, Hiroyuki; Fujiwara, Mikio; Kitamura, Mitsuo; Ito, Toshiyuki; Shimizu, Ryosuke; Toyoshima, Morio

2017-08-06

Quantum communication and quantum cryptography are expected to enhance the transmission rate and the security (confidentiality of data transmission), respectively. We study a new scheme which can potentially bridge an intermediate region covered by these two schemes, which is referred to as quantum photonic network. The basic framework is information theoretically secure communications in a free space optical (FSO) wiretap channel, in which an eavesdropper has physically limited access to the main channel between the legitimate sender and receiver. We first review a theoretical framework to quantify the optimal balance of the transmission efficiency and the security level under power constraint and at finite code length. We then present experimental results on channel characterization based on 10 MHz on-off keying transmission in a 7.8 km terrestrial FSO wiretap channel.This article is part of the themed issue 'Quantum technology for the 21st century'. © 2017 The Author(s).

Torque limit of PM motors for field-weakening region operation

DOEpatents

Royak, Semyon [Beachwood, OH; Harbaugh, Mark M [Richfield, OH

2012-02-14

The invention includes a motor controller and technique for controlling a permanent magnet motor. In accordance with one aspect of the present technique, a permanent magnet motor is controlled by receiving a torque command, determining a physical torque limit based on a stator frequency, determining a theoretical torque limit based on a maximum available voltage and motor inductance ratio, and limiting the torque command to the smaller of the physical torque limit and the theoretical torque limit. Receiving the torque command may include normalizing the torque command to obtain a normalized torque command, determining the physical torque limit may include determining a normalized physical torque limit, determining a theoretical torque limit may include determining a normalized theoretical torque limit, and limiting the torque command may include limiting the normalized torque command to the smaller of the normalized physical torque limit and the normalized theoretical torque limit.

The Quantum Measurement Problem and Physical reality: A Computation Theoretic Perspective

NASA Astrophysics Data System (ADS)

Srikanth, R.

2006-11-01

Is the universe computable? If yes, is it computationally a polynomial place? In standard quantum mechanics, which permits infinite parallelism and the infinitely precise specification of states, a negative answer to both questions is not ruled out. On the other hand, empirical evidence suggests that NP-complete problems are intractable in the physical world. Likewise, computational problems known to be algorithmically uncomputable do not seem to be computable by any physical means. We suggest that this close correspondence between the efficiency and power of abstract algorithms on the one hand, and physical computers on the other, finds a natural explanation if the universe is assumed to be algorithmic; that is, that physical reality is the product of discrete sub-physical information processing equivalent to the actions of a probabilistic Turing machine. This assumption can be reconciled with the observed exponentiality of quantum systems at microscopic scales, and the consequent possibility of implementing Shor's quantum polynomial time algorithm at that scale, provided the degree of superposition is intrinsically, finitely upper-bounded. If this bound is associated with the quantum-classical divide (the Heisenberg cut), a natural resolution to the quantum measurement problem arises. From this viewpoint, macroscopic classicality is an evidence that the universe is in BPP, and both questions raised above receive affirmative answers. A recently proposed computational model of quantum measurement, which relates the Heisenberg cut to the discreteness of Hilbert space, is briefly discussed. A connection to quantum gravity is noted. Our results are compatible with the philosophy that mathematical truths are independent of the laws of physics.

Cortical Neural Computation by Discrete Results Hypothesis

PubMed Central

Castejon, Carlos; Nuñez, Angel

2016-01-01

One of the most challenging problems we face in neuroscience is to understand how the cortex performs computations. There is increasing evidence that the power of the cortical processing is produced by populations of neurons forming dynamic neuronal ensembles. Theoretical proposals and multineuronal experimental studies have revealed that ensembles of neurons can form emergent functional units. However, how these ensembles are implicated in cortical computations is still a mystery. Although cell ensembles have been associated with brain rhythms, the functional interaction remains largely unclear. It is still unknown how spatially distributed neuronal activity can be temporally integrated to contribute to cortical computations. A theoretical explanation integrating spatial and temporal aspects of cortical processing is still lacking. In this Hypothesis and Theory article, we propose a new functional theoretical framework to explain the computational roles of these ensembles in cortical processing. We suggest that complex neural computations underlying cortical processing could be temporally discrete and that sensory information would need to be quantized to be computed by the cerebral cortex. Accordingly, we propose that cortical processing is produced by the computation of discrete spatio-temporal functional units that we have called “Discrete Results” (Discrete Results Hypothesis). This hypothesis represents a novel functional mechanism by which information processing is computed in the cortex. Furthermore, we propose that precise dynamic sequences of “Discrete Results” is the mechanism used by the cortex to extract, code, memorize and transmit neural information. The novel “Discrete Results” concept has the ability to match the spatial and temporal aspects of cortical processing. We discuss the possible neural underpinnings of these functional computational units and describe the empirical evidence supporting our hypothesis. We propose that fast-spiking (FS) interneuron may be a key element in our hypothesis providing the basis for this computation. PMID:27807408

Cortical Neural Computation by Discrete Results Hypothesis.

PubMed

Castejon, Carlos; Nuñez, Angel

2016-01-01

One of the most challenging problems we face in neuroscience is to understand how the cortex performs computations. There is increasing evidence that the power of the cortical processing is produced by populations of neurons forming dynamic neuronal ensembles. Theoretical proposals and multineuronal experimental studies have revealed that ensembles of neurons can form emergent functional units. However, how these ensembles are implicated in cortical computations is still a mystery. Although cell ensembles have been associated with brain rhythms, the functional interaction remains largely unclear. It is still unknown how spatially distributed neuronal activity can be temporally integrated to contribute to cortical computations. A theoretical explanation integrating spatial and temporal aspects of cortical processing is still lacking. In this Hypothesis and Theory article, we propose a new functional theoretical framework to explain the computational roles of these ensembles in cortical processing. We suggest that complex neural computations underlying cortical processing could be temporally discrete and that sensory information would need to be quantized to be computed by the cerebral cortex. Accordingly, we propose that cortical processing is produced by the computation of discrete spatio-temporal functional units that we have called "Discrete Results" (Discrete Results Hypothesis). This hypothesis represents a novel functional mechanism by which information processing is computed in the cortex. Furthermore, we propose that precise dynamic sequences of "Discrete Results" is the mechanism used by the cortex to extract, code, memorize and transmit neural information. The novel "Discrete Results" concept has the ability to match the spatial and temporal aspects of cortical processing. We discuss the possible neural underpinnings of these functional computational units and describe the empirical evidence supporting our hypothesis. We propose that fast-spiking (FS) interneuron may be a key element in our hypothesis providing the basis for this computation.

PERCEIVED AUTONOMY SUPPORT AND BEHAVIORAL ENGAGEMENT IN PHYSICAL EDUCATION: A CONDITIONAL PROCESS MODEL OF POSITIVE EMOTION AND AUTONOMOUS MOTIVATION.

PubMed

Yoo, Jin

2015-06-01

A variety of theoretical perspectives describe the crucial behavioral roles of motivation and emotion, but how these interact with perceptions of social contexts and behaviors is less well understood. This study examined whether autonomous motivation mediated the relationship between perceived autonomy support and behavioral engagement in physical education and whether this mediating process was moderated by positive emotion. A sample of 592 Korean middle-school students (304 boys, 288 girls; M age = 14.0 yr., SD = 0.8) completed questionnaires. Autonomous motivation partially mediated the positive association between perceived autonomy support and behavioral engagement. Positive emotion moderated the relationship between autonomous motivation and behavioral engagement. This indirect link was stronger as positive emotion increased. These findings suggest the importance of integrating emotion into motivational processes to understand how and when perceived autonomy support is associated with behavioral engagement in physical education.

Information Retrieval: A Sequential Learning Process.

ERIC Educational Resources Information Center

Bookstein, Abraham

1983-01-01

Presents decision-theoretic models which intrinsically include retrieval of multiple documents whereby system responds to request by presenting documents to patron in sequence, gathering feedback, and using information to modify future retrievals. Document independence model, set retrieval model, sequential retrieval model, learning model,…

Cosmological history in York time: inflation and perturbations

NASA Astrophysics Data System (ADS)

Roser, Philipp; Valentini, Antony

2017-02-01

The constant mean extrinsic curvature on a spacelike slice may constitute a physically preferred time coordinate, `York time'. One line of enquiry to probe this idea is to understand processes in our cosmological history in terms of York time. Following a review of the theoretical motivations, we focus on slow-roll inflation and the freezing and Hubble re-entry of cosmological perturbations. While the physics is, of course, observationally equivalent, we show how the mathematical account of these processes is distinct from the conventional account in terms of standard cosmological or conformal time. We also consider the cosmological York-timeline more broadly and contrast it with the conventional cosmological timeline.

Abstracts of Research. July 1974-June 1975.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. Computer and Information Science Research Center.

Abstracts of research papers in computer and information science are given for 68 papers in the areas of information storage and retrieval; human information processing; information analysis; linguistic analysis; artificial intelligence; information processes in physical, biological, and social systems; mathematical techniques; systems…

Information-Theoretical Complexity Analysis of Selected Elementary Chemical Reactions

NASA Astrophysics Data System (ADS)

Molina-Espíritu, M.; Esquivel, R. O.; Dehesa, J. S.

We investigate the complexity of selected elementary chemical reactions (namely, the hydrogenic-abstraction reaction and the identity SN2 exchange reaction) by means of the following single and composite information-theoretic measures: disequilibrium (D), exponential entropy(L), Fisher information (I), power entropy (J), I-D, D-L and I-J planes and Fisher-Shannon (FS) and Lopez-Mancini-Calbet (LMC) shape complexities. These quantities, which are functionals of the one-particle density, are computed in both position (r) and momentum (p) spaces. The analysis revealed that the chemically significant regions of these reactions can be identified through most of the single information-theoretic measures and the two-component planes, not only the ones which are commonly revealed by the energy, such as the reactant/product (R/P) and the transition state (TS), but also those that are not present in the energy profile such as the bond cleavage energy region (BCER), the bond breaking/forming regions (B-B/F) and the charge transfer process (CT). The analysis of the complexities shows that the energy profile of the abstraction reaction bears the same information-theoretical features of the LMC and FS measures, however for the identity SN2 exchange reaction does not hold a simple behavior with respect to the LMC and FS measures. Most of the chemical features of interest (BCER, B-B/F and CT) are only revealed when particular information-theoretic aspects of localizability (L or J), uniformity (D) and disorder (I) are considered.

Annoyance or Delight? College Students' Perspectives on Looking for Information

ERIC Educational Resources Information Center

Denison, Denise R.; Montgomery, Diane

2012-01-01

This study examined the ways that students describe how they look for information for a research project. Sternberg's Triarchic Theory of Intelligence was used to theoretically choose the statements that were sorted by the participants to determine the perceptions of the information-seeking process. Using Q methodology as the research strategy,…

MarChem 93, The Proceedings, The 1993 Workshop on Marine Chemistry Instrumentation

DTIC Science & Technology

1994-01-01

technologies that are becom- chemical analysis, and record keeping ing available was tempered by the processes . These advances could be (largely...surface and meet the future needs of the chemical near bottom samples. oceanography research community? If not, how should they be improved? Difficulty...theoretical models where applicable (from box to embedded mixing and circulation) linking physical, biological, and chemical processes . I I I EDWARD J

Physically representative atomistic modeling of atomic-scale friction

NASA Astrophysics Data System (ADS)

Dong, Yalin

Nanotribology is a research field to study friction, adhesion, wear and lubrication occurred between two sliding interfaces at nano scale. This study is motivated by the demanding need of miniaturization mechanical components in Micro Electro Mechanical Systems (MEMS), improvement of durability in magnetic storage system, and other industrial applications. Overcoming tribological failure and finding ways to control friction at small scale have become keys to commercialize MEMS with sliding components as well as to stimulate the technological innovation associated with the development of MEMS. In addition to the industrial applications, such research is also scientifically fascinating because it opens a door to understand macroscopic friction from the most bottom atomic level, and therefore serves as a bridge between science and engineering. This thesis focuses on solid/solid atomic friction and its associated energy dissipation through theoretical analysis, atomistic simulation, transition state theory, and close collaboration with experimentalists. Reduced-order models have many advantages for its simplification and capacity to simulating long-time event. We will apply Prandtl-Tomlinson models and their extensions to interpret dry atomic-scale friction. We begin with the fundamental equations and build on them step-by-step from the simple quasistatic one-spring, one-mass model for predicting transitions between friction regimes to the two-dimensional and multi-atom models for describing the effect of contact area. Theoretical analysis, numerical implementation, and predicted physical phenomena are all discussed. In the process, we demonstrate the significant potential for this approach to yield new fundamental understanding of atomic-scale friction. Atomistic modeling can never be overemphasized in the investigation of atomic friction, in which each single atom could play a significant role, but is hard to be captured experimentally. In atomic friction, the interesting physical process is buried between the two contact interfaces, thus makes a direct measurement more difficult. Atomistic simulation is able to simulate the process with the dynamic information of each single atom, and therefore provides valuable interpretations for experiments. In this, we will systematically to apply Molecular Dynamics (MD) simulation to optimally model the Atomic Force Microscopy (AFM) measurement of atomic friction. Furthermore, we also employed molecular dynamics simulation to correlate the atomic dynamics with the friction behavior observed in experiments. For instance, ParRep dynamics (an accelerated molecular dynamic technique) is introduced to investigate velocity dependence of atomic friction; we also employ MD simulation to "see" how the reconstruction of gold surface modulates the friction, and the friction enhancement mechanism at a graphite step edge. Atomic stick-slip friction can be treated as a rate process. Instead of running a direction simulation of the process, we can apply transition state theory to predict its property. We will have a rigorous derivation of velocity and temperature dependence of friction based on the Prandtl-Tomlinson model as well as transition theory. A more accurate relation to prediction velocity and temperature dependence is obtained. Furthermore, we have included instrumental noise inherent in AFM measurement to interpret two discoveries in experiments, suppression of friction at low temperature and the attempt frequency discrepancy between AFM measurement and theoretical prediction. We also discuss the possibility to treat wear as a rate process.

III International Conference on Laser and Plasma Researches and Technologies

NASA Astrophysics Data System (ADS)

2017-12-01

A.P. Kuznetsov and S.V. Genisaretskaya III Conference on Plasma and Laser Research and Technologies took place on January 24th until January 27th, 2017 at the National Research Nuclear University "MEPhI" (NRNU MEPhI). The Conference was organized by the Institute for Laser and Plasma Technologies and was supported by the Competitiveness Program of NRNU MEPhI. The conference program consisted of nine sections: • Laser physics and its application • Plasma physics and its application • Laser, plasma and radiation technologies in industry • Physics of extreme light fields • Controlled thermonuclear fusion • Modern problems of theoretical physics • Challenges in physics of solid state, functional materials and nanosystems • Particle accelerators and radiation technologies • Modern trends of quantum metrology. The conference is based on scientific fields as follows: • Laser, plasma and radiation technologies in industry, energetic, medicine; • Photonics, quantum metrology, optical information processing; • New functional materials, metamaterials, “smart” alloys and quantum systems; • Ultrahigh optical fields, high-power lasers, Mega Science facilities; • High-temperature plasma physics, environmentally-friendly energetic based on controlled thermonuclear fusion; • Spectroscopic synchrotron, neutron, laser research methods, quantum mechanical calculation and computer modelling of condensed media and nanostructures. More than 250 specialists took part in the Conference. They represented leading Russian scientific research centers and universities (National Research Centre "Kurchatov Institute", A.M. Prokhorov General Physics Institute, P.N. Lebedev Physical Institute, Troitsk Institute for Innovation and Fusion Research, Joint Institute for Nuclear Research, Moscow Institute of Physics and Tecnology and others) and leading scientific centers and universities from Germany, France, USA, Canada, Japan. We would like to thank heartily all of the speakers, participants, organizing and program committee members for their contribution to the conference.

Input-Based Approaches to Teaching Grammar: A Review of Classroom-Oriented Research.

ERIC Educational Resources Information Center

Ellis, Rod

1999-01-01

Examines the theoretical rationales (universal grammar, information-processing theories, skill-learning theories) for input-based grammar teaching and reviews classroom-oriented research (i.e., enriched-input studies, input-processing studies) that has integrated this option. (Author/VWL)

Cognitive Theory. Volume 2.

ERIC Educational Resources Information Center

Castellan, N. John, Jr., Ed.; And Others

The conference papers in this collection emphasize the theoretical significance of their authors' work in the areas of mathematical and cognitive psychology. Major topics considered include facilitation of problem solving; psychological differences among problem isomorphs; the process of understanding in problem solving; processing information for…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tschudi, T.; Herden, A.; Goltz, J.

A theoretical and experimental study of two- and four-wave mixing in photorefractive crystals (BaTiO/sub 3/) is presented, giving special priority to image amplification in optical information processing systems.

Steady-state, cavityless, multimode superradiance in a cold vapor

NASA Astrophysics Data System (ADS)

Greenberg, Joel A.; Gauthier, Daniel J.

2012-07-01

We demonstrate steady-state, mirrorless superradiance in a cold vapor pumped by weak optical fields. Beyond a critical pump intensity of 1 mW/cm2, the vapor spontaneously transforms into a spatially self-organized state: a density grating forms. Scattering of the pump beams off this grating generates a pair of new, intense optical fields that act back on the vapor to enhance the atomic organization. We map out experimentally the superradiant phase transition boundary and show that it is well described by our theoretical model. The resulting superradiant emission is nearly coherent, persists for several seconds, displays strong temporal correlations between the various modes, and has a coherence time of several hundred μs. This system therefore has applications in fundamental studies of many-body physics with long-range interactions as well as all-optical and quantum information processing.

Special issue on cluster algebras in mathematical physics

NASA Astrophysics Data System (ADS)

Di Francesco, Philippe; Gekhtman, Michael; Kuniba, Atsuo; Yamazaki, Masahito

2013-10-01

This is a call for contributions to a special issue of Journal of Physics A: Mathematical and Theoretical dedicated to cluster algebras in mathematical physics. Over the ten years since their introduction by Fomin and Zelevinsky, the theory of cluster algebras has witnessed a spectacular growth, first and foremost due to the many links that have been discovered with a wide range of subjects in mathematics and, increasingly, theoretical and mathematical physics. The main motivation of this special issue is to gather together reviews, recent developments and open problems, mainly from a mathematical physics viewpoint, into a single comprehensive issue. We expect that such a special issue will become a valuable reference for the broad scientific community working in mathematical and theoretical physics. The issue will consist of invited review articles and contributed papers containing new results on the interplays of cluster algebras with mathematical physics. Editorial policy The Guest Editors for this issue are Philippe Di Francesco, Michael Gekhtman, Atsuo Kuniba and Masahito Yamazaki. The areas and topics for this issue include, but are not limited to: discrete integrable systems arising from cluster mutations cluster structure on Poisson varieties cluster algebras and soliton interactions cluster positivity conjecture Y-systems in the thermodynamic Bethe ansatz and Zamolodchikov's periodicity conjecture T-system of transfer matrices of integrable lattice models dilogarithm identities in conformal field theory wall crossing in 4d N = 2 supersymmetric gauge theories 4d N = 1 quiver gauge theories described by networks scattering amplitudes of 4d N = 4 theories 3d N = 2 gauge theories described by flat connections on 3-manifolds integrability of dimer/Ising models on graphs. All contributions will be refereed and processed according to the usual procedure of the journal. Guidelines for preparation of contributions The deadline for contributed papers is 31 March 2014. This deadline will allow the special issue to appear at the end of 2014. There is no strict regulation on article size, but as a guide the preferable size is 15-30 pages for contributed papers and 40-60 pages for reviews. Further advice on publishing your work in Journal of Physics A may be found at iopscience.iop.org/jphysa. Contributions to the special issue should be submitted by web upload via authors.iop.org/, or by email to jphysa@iop.org, quoting 'JPhysA special issue on cluster algebras in mathematical physics'. Submissions should ideally be in standard LaTeX form. Please see the website for further information on electronic submissions. All contributions should be accompanied by a read-me file or covering letter giving the postal and e-mail addresses for correspondence. The Publishing Office should be notified of any subsequent change of address. The special issue will be published in the print and online versions of the journal.

Granger Causality and Transfer Entropy Are Equivalent for Gaussian Variables

NASA Astrophysics Data System (ADS)

Barnett, Lionel; Barrett, Adam B.; Seth, Anil K.

2009-12-01

Granger causality is a statistical notion of causal influence based on prediction via vector autoregression. Developed originally in the field of econometrics, it has since found application in a broader arena, particularly in neuroscience. More recently transfer entropy, an information-theoretic measure of time-directed information transfer between jointly dependent processes, has gained traction in a similarly wide field. While it has been recognized that the two concepts must be related, the exact relationship has until now not been formally described. Here we show that for Gaussian variables, Granger causality and transfer entropy are entirely equivalent, thus bridging autoregressive and information-theoretic approaches to data-driven causal inference.

Education and Research in the SEENET-MTP Regional Framework for Higher Education in Physics

NASA Astrophysics Data System (ADS)

Constantinescu, R.; Djordjevic, G. S.

2010-01-01

Southeastern European countries undergo significant changes in the demand/supply ratio on the labour market and in the structure of professional competences that are necessary for undertaking a professional activity. In addition, brain-drain process and decrease of interest for a career in basic sciences put many challenges for our community. Consequently, based on the activity of the Southeastern European Network in Mathematical and Theoretical Physics (SEENET MTP Network) in connecting groups and persons working in mathematics and theoretical physics, we investigate specific qualifications recognized in these fields in all the countries from the region, and the related competences necessary for practising the respective occupations. A list of new possible occupations will be promoted for inclusion in the National Qualifications Register for Higher Education. Finally, we analyze the vision existing in this region on the higher education qualifications against the European vision and experience, in particular in training of Master students, PhD students, and senior teaching and research staff through the Network, i.e. multilateral and bilateral programs.

Delivery and Receipt of a Self-Determination-Theory-Based Extracurricular Physical Activity Intervention: Exploring Theoretical Fidelity in Action 3:30.

PubMed

Sebire, Simon J; Edwards, Mark J; Fox, Kenneth R; Davies, Ben; Banfield, Kathryn; Wood, Lesley; Jago, Russell

2016-08-01

The implementation, fidelity, and receipt of a self-determination-theory-based after-school physical activity intervention (Action 3:30) delivered by teaching assistants (TAs) was examined using a mixed-methods process evaluation. Physical activity motivation and need satisfaction were reported by 539 participants at baseline, the end of intervention, and 4-month follow-up. Pupil- and TA-reported autonomy-support and teaching efficacy were collected alongside interviews with 18 TAs and focus groups with 60 participants. Among intervention boys there were small increases in identified, introjected, and external motivation and no differences in need satisfaction. Among girls, intrinsic and identified motivation and autonomy and relatedness were lower in the intervention group. Qualitative evidence for fidelity was moderate, and boys reported greater need satisfaction than girls. TAs provided greater structure than involvement or autonomy-support and felt least efficacious when facing school-based challenges. The findings highlight the refinements needed to enhance theoretical fidelity and intervention effectiveness for boys and girls.

Preface: Special Topic on Single-Molecule Biophysics

NASA Astrophysics Data System (ADS)

Makarov, Dmitrii E.; Schuler, Benjamin

2018-03-01

Single-molecule measurements are now almost routinely used to study biological systems and processes. The scope of this special topic emphasizes the physics side of single-molecule observations, with the goal of highlighting new developments in physical techniques as well as conceptual insights that single-molecule measurements bring to biophysics. This issue also comprises recent advances in theoretical physical models of single-molecule phenomena, interpretation of single-molecule signals, and fundamental areas of statistical mechanics that are related to single-molecule observations. A particular goal is to illustrate the increasing synergy between theory, simulation, and experiment in single-molecule biophysics.

Conjoint-measurement framework for the study of probabilistic information processing.

NASA Technical Reports Server (NTRS)

Wallsten, T. S.

1972-01-01

The theory of conjoint measurement described by Krantz et al. (1971) is shown to indicate how a descriptive model of human processing of probabilistic information built around Bayes' rule is to be tested and how it is to be used to obtain subjective scale values. Specific relationships concerning these scale values are shown to emerge, and the theoretical prospects resulting from this development are discussed.

Information-theoretic decomposition of embodied and situated systems.

PubMed

Da Rold, Federico

2018-07-01

The embodied and situated view of cognition stresses the importance of real-time and nonlinear bodily interaction with the environment for developing concepts and structuring knowledge. In this article, populations of robots controlled by an artificial neural network learn a wall-following task through artificial evolution. At the end of the evolutionary process, time series are recorded from perceptual and motor neurons of selected robots. Information-theoretic measures are estimated on pairings of variables to unveil nonlinear interactions that structure the agent-environment system. Specifically, the mutual information is utilized to quantify the degree of dependence and the transfer entropy to detect the direction of the information flow. Furthermore, the system is analyzed with the local form of such measures, thus capturing the underlying dynamics of information. Results show that different measures are interdependent and complementary in uncovering aspects of the robots' interaction with the environment, as well as characteristics of the functional neural structure. Therefore, the set of information-theoretic measures provides a decomposition of the system, capturing the intricacy of nonlinear relationships that characterize robots' behavior and neural dynamics. Copyright © 2018 Elsevier Ltd. All rights reserved.

On the electrophilic character of molecules through its relation with electronegativity and chemical hardness.

PubMed

Islam, Nazmul; Ghosh, Dulal C

2012-01-01

Electrophilicity is an intrinsic property of atoms and molecules. It probably originates logistically with the involvement in the physical process of electrostatics of soaked charge in electronic shells and the screened nuclear charge of atoms. Motivated by the existing view of conceptual density functional theory that similar to electronegativity and hardness equalization, there should be a physical process of equalization of electrophilicity during the chemical process of formation of hetero nuclear molecules, we have developed a new theoretical scheme and formula for evaluating the electrophilicity of hetero nuclear molecules. A comparative study with available bench marking reveals that the hypothesis of electrophilicity and equalization, and the present method of evaluating equalized electrophilicity, are scientifically promising.

On the Electrophilic Character of Molecules Through Its Relation with Electronegativity and Chemical Hardness

PubMed Central

Islam, Nazmul; Ghosh, Dulal C.

2012-01-01

Electrophilicity is an intrinsic property of atoms and molecules. It probably originates logistically with the involvement in the physical process of electrostatics of soaked charge in electronic shells and the screened nuclear charge of atoms. Motivated by the existing view of conceptual density functional theory that similar to electronegativity and hardness equalization, there should be a physical process of equalization of electrophilicity during the chemical process of formation of hetero nuclear molecules, we have developed a new theoretical scheme and formula for evaluating the electrophilicity of hetero nuclear molecules. A comparative study with available bench marking reveals that the hypothesis of electrophilicity and equalization, and the present method of evaluating equalized electrophilicity, are scientifically promising. PMID:22408445

Development of a Theory-Based Intervention to Increase Clinical Measurement of Reactive Balance in Adults at Risk of Falls.

PubMed

Sibley, Kathryn M; Brooks, Dina; Gardner, Paula; Janaudis-Ferreira, Tania; McGlynn, Mandy; OʼHoski, Sachi; McEwen, Sara; Salbach, Nancy M; Shaffer, Jennifer; Shing, Paula; Straus, Sharon E; Jaglal, Susan B

2016-04-01

Effective balance reactions are essential for avoiding falls, but are not regularly measured by physical therapists. Physical therapists report wanting to improve reactive balance assessment, and theory-based approaches are recommended as the foundation for the development of interventions. This article describes how a behavior change theory for health care providers, the theoretical domains framework (TDF), was used to develop an intervention to increase reactive balance measurement among physical therapists who work in rehabilitation settings and treat adults who are at risk of falls. We employed published recommendations for using the TDF-guided intervention development. We identified what health care provider behavior is in need of change, relevant barriers and facilitators, strategies to address them, and how we would measure behavior change. In this case, identifying strategies required selecting both a reactive balance measure and behavior change techniques. Previous research had determined that physical therapists need to increase reactive balance measurement, and identified barriers and facilitators that corresponded to 8 TDF domains. A published review informed the selection of the Balance Evaluation Systems Test (Reactive Postural Responses Section) as addressing the barriers and facilitators, and existing research informed the selection of 9 established behavior change techniques corresponding to each identified TDF domain. The TDF framework were incorporated into a 12-month intervention with interactive group sessions, local champions, and health record modifications. Intervention effect can be evaluated using health record abstraction, questionnaires, and qualitative semistructured interviews. Although future research will evaluate the intervention in a controlled study, the process of theory-based intervention development can be applied to other rehabilitation research contexts, maximizing the impact of this work.Video Abstract is available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A123).

Theoretical Technology Research for ISTP/SOLARMAX

NASA Technical Reports Server (NTRS)

Ashour-Abdalla, Maha; Acuna, Mario (Technical Monitor)

2000-01-01

During the last decade, we have been developing theoretical tools to support the scientific objectives of the International Solar Terrestrial Physics (ISTP) program. Results from our mission-oriented theory program have contributed significantly to the development of predictive capabilities by using real upstream solar wind conditions as input to our models and forecasting events observed downstream near Earth. We also developed the capability to unravel the complex information contained in ion velocity distribution functions measured near the Earth to determine their origin and energization process. During solar maximum, solar flares and coronal mass ejections (CMEs) dominate the sun's activity. It is now widely accepted that the impact of CMEs (or magnetic clouds) with the Earth's magnetosphere is the cause of most magnetic storms during solar maximum. One important aspect of a CME is the occurrence of solar energetic particle (SEP) events. During these events, protons, electrons, and heavy ions of solar origin are accelerated to very high energies by shock waves driven out from the sun. We carried out a series of large-scale kinetic (LSK) simulations to model the effect of SEPs on the near-Earth environment and the accessibility of these high-energy particles to the inner magnetosphere. We present the results of these studies.

New theoretical models and ratio imaging techniques associated with the NASA earth resources spectral information system

NASA Technical Reports Server (NTRS)

Vincent, R. K.

1974-01-01

Four independent investigations are reported; in general these are concerned with improving and utilizing the correlation between the physical properties of natural materials as evidenced in laboratory spectra and spectral data collected by multispectral scanners. In one investigation, two theoretical models were devised that permit the calculation of spectral emittance spectra for rock and mineral surfaces of various particle sizes. The simpler of the two models can be used to qualitatively predict the effect of texture on the spectral emittance of rocks and minerals; it is also potentially useful as an aid in predicting the identification of natural atmospheric aerosol constituents. The second investigation determined, via an infrared ratio imaging technique, the best pair of infrared filters for silicate rock-type discrimination. In a third investigation, laboratory spectra of natural materials were compressed into 11-digit ratio codes for use in feature selection, in searches for false alarm candidates, and eventually for use as training sets in completely automatic data processors. In the fourth investigation, general outlines of a ratio preprocessor and an automatic recognition map processor are developed for on-board data processing in the space shuttle era.

Database and Related Activities in Japan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murakami, Izumi; Kato, Daiji; Kato, Masatoshi

2011-05-11

We have constructed and made available atomic and molecular (AM) numerical databases on collision processes such as electron-impact excitation and ionization, recombination and charge transfer of atoms and molecules relevant for plasma physics, fusion research, astrophysics, applied-science plasma, and other related areas. The retrievable data is freely accessible via the internet. We also work on atomic data evaluation and constructing collisional-radiative models for spectroscopic plasma diagnostics. Recently we have worked on Fe ions and W ions theoretically and experimentally. The atomic data and collisional-radiative models for these ions are examined and applied to laboratory plasmas. A visible M1 transition ofmore » W{sup 26+} ion is identified at 389.41 nm by EBIT experiments and theoretical calculations. We have small non-retrievable databases in addition to our main database. Recently we evaluated photo-absorption cross sections for 9 atoms and 23 molecules and we present them as a new database. We established a new association ''Forum of Atomic and Molecular Data and Their Applications'' to exchange information among AM data producers, data providers and data users in Japan and we hope this will help to encourage AM data activities in Japan.« less

Database and Related Activities in Japan

NASA Astrophysics Data System (ADS)

Murakami, Izumi; Kato, Daiji; Kato, Masatoshi; Sakaue, Hiroyuki A.; Kato, Takako; Ding, Xiaobin; Morita, Shigeru; Kitajima, Masashi; Koike, Fumihiro; Nakamura, Nobuyuki; Sakamoto, Naoki; Sasaki, Akira; Skobelev, Igor; Tsuchida, Hidetsugu; Ulantsev, Artemiy; Watanabe, Tetsuya; Yamamoto, Norimasa

2011-05-01

We have constructed and made available atomic and molecular (AM) numerical databases on collision processes such as electron-impact excitation and ionization, recombination and charge transfer of atoms and molecules relevant for plasma physics, fusion research, astrophysics, applied-science plasma, and other related areas. The retrievable data is freely accessible via the internet. We also work on atomic data evaluation and constructing collisional-radiative models for spectroscopic plasma diagnostics. Recently we have worked on Fe ions and W ions theoretically and experimentally. The atomic data and collisional-radiative models for these ions are examined and applied to laboratory plasmas. A visible M1 transition of W26+ ion is identified at 389.41 nm by EBIT experiments and theoretical calculations. We have small non-retrievable databases in addition to our main database. Recently we evaluated photo-absorption cross sections for 9 atoms and 23 molecules and we present them as a new database. We established a new association "Forum of Atomic and Molecular Data and Their Applications" to exchange information among AM data producers, data providers and data users in Japan and we hope this will help to encourage AM data activities in Japan.

Testing a Theoretical Model of Immigration Transition and Physical Activity.

PubMed

Chang, Sun Ju; Im, Eun-Ok

2015-01-01

The purposes of the study were to develop a theoretical model to explain the relationships between immigration transition and midlife women's physical activity and test the relationships among the major variables of the model. A theoretical model, which was developed based on transitions theory and the midlife women's attitudes toward physical activity theory, consists of 4 major variables, including length of stay in the United States, country of birth, level of acculturation, and midlife women's physical activity. To test the theoretical model, a secondary analysis with data from 127 Hispanic women and 123 non-Hispanic (NH) Asian women in a national Internet study was used. Among the major variables of the model, length of stay in the United States was negatively associated with physical activity in Hispanic women. Level of acculturation in NH Asian women was positively correlated with women's physical activity. Country of birth and level of acculturation were significant factors that influenced physical activity in both Hispanic and NH Asian women. The findings support the theoretical model that was developed to examine relationships between immigration transition and physical activity; it shows that immigration transition can play an essential role in influencing health behaviors of immigrant populations in the United States. The NH theoretical model can be widely used in nursing practice and research that focus on immigrant women and their health behaviors. Health care providers need to consider the influences of immigration transition to promote immigrant women's physical activity.

A simplified computational memory model from information processing.

PubMed

Zhang, Lanhua; Zhang, Dongsheng; Deng, Yuqin; Ding, Xiaoqian; Wang, Yan; Tang, Yiyuan; Sun, Baoliang

2016-11-23

This paper is intended to propose a computational model for memory from the view of information processing. The model, called simplified memory information retrieval network (SMIRN), is a bi-modular hierarchical functional memory network by abstracting memory function and simulating memory information processing. At first meta-memory is defined to express the neuron or brain cortices based on the biology and graph theories, and we develop an intra-modular network with the modeling algorithm by mapping the node and edge, and then the bi-modular network is delineated with intra-modular and inter-modular. At last a polynomial retrieval algorithm is introduced. In this paper we simulate the memory phenomena and functions of memorization and strengthening by information processing algorithms. The theoretical analysis and the simulation results show that the model is in accordance with the memory phenomena from information processing view.

Planetary geology: Impact processes on asteroids

NASA Technical Reports Server (NTRS)

Chapman, C. R.; Davis, D. R.; Greenberg, R.; Weidenschilling, S. J.

1982-01-01

The fundamental geological and geophysical properties of asteroids were studied by theoretical and simulation studies of their collisional evolution. Numerical simulations incorporating realistic physical models were developed to study the collisional evolution of hypothetical asteroid populations over the age of the solar system. Ideas and models are constrained by the observed distributions of sizes, shapes, and spin rates in the asteroid belt, by properties of Hirayama families, and by experimental studies of cratering and collisional phenomena. It is suggested that many asteroids are gravitationally-bound "rubble piles.' Those that rotate rapidly may have nonspherical quasi-equilibrium shapes, such as ellipsoids or binaries. Through comparison of models with astronomical data, physical properties of these asteroids (including bulk density) are determined, and physical processes that have operated in the solar system in primordial and subsequent epochs are studied.

Physical activity adoption to adherence, lapse, and dropout: a self-determination theory perspective.

PubMed

Kinnafick, Florence-Emilie; Thøgersen-Ntoumani, Cecilie; Duda, Joan L

2014-05-01

Grounded in Self-Determination Theory, we aimed to explore and identify key motivational processes involved in the transition from a physically inactive to an active lifestyle, and the processes involved in lapse and dropout behavior within a walking program. We implemented a qualitative, longitudinal case study method, using semistructured interviews and theoretical thematic analyses. Fifteen women were interviewed over 10 months and three profiles were generated: (a) nonadherence, (b) lapse/readoption of physical activity, and (c) adherence. Internalization of walking behavior was key to adherence. Satisfaction of the needs for competence and relatedness were central for participation during exercise at the adoption stages, and autonomy was particularly pertinent in facilitating adherence. Those who lapsed and restarted physical activity experienced feelings of autonomy at the point of readoption. Sources of support were driving forces in the adoption and adherence phases.

The unexpected confluence of plasma physics and climate science: On the lives and legacies of Norman Rostoker and Sherry Rowland

NASA Astrophysics Data System (ADS)

Mackey, Katherine R. M.

2016-03-01

The Norman Rostoker Memorial Symposium brought together approximately 150 attendees to share their recent work and to reflect on the contributions of Norman Rostoker to the field of plasma physics and the advancement of fusion as a source of renewable clean energy. The field has changed considerably in a few short decades, with theoretical advances and technological innovations evolving in lock step. Over those same decades, our understanding of human induced climate change has also evolved; measurable changes in Earth's physical, chemical, and biological processes have already been observed, and these will likely intensify in the coming decades. Never before has the need for clean energy been more pronounced, or the need for transformative solutions more pressing. As scientists work with legislators, journalists, and the public to take actions to address the threat of climate change, there is much to be learned from the legacies of innovators like Norman Rostoker, who have tackled complex problems with scientific insight and determination even when the odds were stacked against them. I write this from the perspective on an Earth system scientist who studies photosynthesis and the biogeochemistry of the oceans, and my statements about plasma physics and Norman Rostoker are based on information I gathered from the colloquium and from many enjoyable conversations with his friends and colleagues.

The unexpected confluence of plasma physics and climate science: On the lives and legacies of Norman Rostoker and Sherry Rowland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mackey, Katherine R. M.

The Norman Rostoker Memorial Symposium brought together approximately 150 attendees to share their recent work and to reflect on the contributions of Norman Rostoker to the field of plasma physics and the advancement of fusion as a source of renewable clean energy. The field has changed considerably in a few short decades, with theoretical advances and technological innovations evolving in lock step. Over those same decades, our understanding of human induced climate change has also evolved; measurable changes in Earth’s physical, chemical, and biological processes have already been observed, and these will likely intensify in the coming decades. Never beforemore » has the need for clean energy been more pronounced, or the need for transformative solutions more pressing. As scientists work with legislators, journalists, and the public to take actions to address the threat of climate change, there is much to be learned from the legacies of innovators like Norman Rostoker, who have tackled complex problems with scientific insight and determination even when the odds were stacked against them. I write this from the perspective on an Earth system scientist who studies photosynthesis and the biogeochemistry of the oceans, and my statements about plasma physics and Norman Rostoker are based on information I gathered from the colloquium and from many enjoyable conversations with his friends and colleagues.« less

Composition of the Solar Wind

NASA Technical Reports Server (NTRS)

Suess, S. T.

2007-01-01

The solar wind reflects the composition of the Sun and physical processes in the corona. Analysis produces information on how the solar system was formed and on physical processes in the corona. The analysis can also produce information on the local interstellar medium, galactic evolution, comets in the solar wind, dust in the heliosphere, and matter escaping from planets.

Developing and applying habitat models using forest inventory data: an example using a terrestrial salamander

Treesearch

Hartwell H. Welsh Jr; Jeffrey R. Dunk; William J. Zielinski

2004-01-01

We provide a framework for developing predictive species habitat models using preexisting vegetation, physical, and spatial data in association with animal sampling data. The resulting models are used to evaluate questions relevant to species conservation, in particular, comparing occurrence estimates in reserved and unreserved lands. We used an information–theoretic...

Scaling Laws for Heterogeneous Wireless Networks

DTIC Science & Technology

2009-09-01

planned and the size of communication networks that are fundamentally understood. On the one hand, wireline networks (like the Internet) have grown from...Franceschetti, Marco D. Migliore, and Paolo Minero . The capacity of wireless networks: Information-theoretic and physical limits. In Proceedings of the...Allerton Conference on Communication, Control, and Computing, September 2007. [12] Massimo Franceschetti, Marco D. Migliore, and Paolo Minero . The

Quantum effects in the understanding of consciousness.

PubMed

Hameroff, Stuart R; Craddock, Travis J A; Tuszynski, Jack A

2014-06-01

This paper presents a historical perspective on the development and application of quantum physics methodology beyond physics, especially in biology and in the area of consciousness studies. Quantum physics provides a conceptual framework for the structural aspects of biological systems and processes via quantum chemistry. In recent years individual biological phenomena such as photosynthesis and bird navigation have been experimentally and theoretically analyzed using quantum methods building conceptual foundations for quantum biology. Since consciousness is attributed to human (and possibly animal) mind, quantum underpinnings of cognitive processes are a logical extension. Several proposals, especially the Orch OR hypothesis, have been put forth in an effort to introduce a scientific basis to the theory of consciousness. At the center of these approaches are microtubules as the substrate on which conscious processes in terms of quantum coherence and entanglement can be built. Additionally, Quantum Metabolism, quantum processes in ion channels and quantum effects in sensory stimulation are discussed in this connection. We discuss the challenges and merits related to quantum consciousness approaches as well as their potential extensions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuo, Rui; Wu, C. F. Jeff

Many computer models contain unknown parameters which need to be estimated using physical observations. Furthermore, the calibration method based on Gaussian process models may lead to unreasonable estimate for imperfect computer models. In this work, we extend their study to calibration problems with stochastic physical data. We propose a novel method, called the L 2 calibration, and show its semiparametric efficiency. The conventional method of the ordinary least squares is also studied. Theoretical analysis shows that it is consistent but not efficient. Here, numerical examples show that the proposed method outperforms the existing ones.

Guide to remote-sensor data systems

NASA Technical Reports Server (NTRS)

Dewitt, R. R.; Ellison, J. L.

1980-01-01

Remote sensing data-handbook presents theoretical and practical information on spaceborne sensors and associated systems for Earth-resources applications. Handbook provides discussion on historical information, principles of operations, factors affecting performances, nature of data output, and system required to process data and trends in research and development.

Nash Equilibria in Theory of Reasoned Action

NASA Astrophysics Data System (ADS)

Almeida, Leando; Cruz, José; Ferreira, Helena; Pinto, Alberto Adrego

2009-08-01

Game theory and Decision Theory have been applied to many different areas such as Physics, Economics, Biology, etc. In its application to Psychology, we introduce, in the literature, a Game Theoretical Model of Planned Behavior or Reasoned Action by establishing an analogy between two specific theories. In this study we take in account that individual decision-making is an outcome of a process where group decisions can determine individual probabilistic behavior. Using Game Theory concepts, we describe how intentions can be transformed in behavior and according to the Nash Equilibrium, this process will correspond to the best individual decision/response taking in account the collective response. This analysis can be extended to several examples based in the Game Theoretical Model of Planned Behavior or Reasoned Action.

Two-potential approach for electron-molecular collisions at intermediate and high energies - Application to e-N2 scatterings

NASA Technical Reports Server (NTRS)

Choi, B. H.; Poe, R. T.; Sun, J. C.; Shan, Y.

1979-01-01

A general theoretical approach is proposed for the calculation of elastic, vibrational, and rotational transitions for electron-molecule scattering at intermediate and high-electron-impact energies. In this formulation, contributions to the scattering process come from the incoherent sum of two dominant potentials: a short-range shielded nuclear Coulomb potential from individual atomic centers, and a permanent/induced long-range potential. Application to e-N2 scattering from 50-500 eV incident electron energies has yielded good agreement with absolutely calibrated experiments. Comparisons with other theoretical approaches are made. The physical picture as well as the general features of electron-molecule scattering process are discussed within the framework of the two-potential approach.

Theoretical study of hydrogen absorption-desorption on LaNi3.8Al1.2-xMnx using statistical physics treatment

NASA Astrophysics Data System (ADS)

Bouaziz, Nadia; Ben Manaa, Marwa; Ben Lamine, Abdelmottaleb

2017-11-01

The hydrogen absorption-desorption isotherms on LaNi3.8Al1.2-xMnx alloy at temperature T = 433 K is studied through various theoretical models. The analytical expressions of these models were deduced exploiting the grand canonical ensemble in statistical physics by taking some simplifying hypotheses. Among these models an adequate model which presents a good correlation with the experimental curves has been selected. The physicochemical parameters intervening in the absorption-desorption processes and involved in the model expressions could be directly deduced from the experimental isotherms by numerical simulation. Six parameters of the model are adjusted, namely the numbers of hydrogen atoms per site n1 and n2, the receptor site densities N1m and N2m, and the energetic parameters P1 and P2. The behaviors of these parameters are discussed in relation with absorption and desorption processes to better understand and compare these phenomena. Thanks to the energetic parameters, we calculated the sorption energies which are typically ranged between 266 and 269.4 KJ/mol for absorption process and between 267 and 269.5 KJ/mol for desorption process comparable to usual chemical bond energies. Using the adopted model expression, the thermodynamic potential functions which govern the absorption/desorption process such as internal energy Eint, free enthalpy of Gibbs G and entropy Sa are derived.

Adult Literacy in the United States: A Compendium of Qualitative Data and Interpretive Comments. Research to Practice.

ERIC Educational Resources Information Center

Armstrong, William B.; Sticht, Thomas G.

Human cognitive system and information processing theories were used as the theoretical base that frames an interpretation of adult literacy research from World War I (WWI) through 1993. These theoretical perspectives are as follows: (1) literacy learning is grounded in a distinct developmental sequence; and (2) literacy learning is dependent on…

Assessing the Effectiveness of E-learning Integration in College Physics in the Alamo Community Colleges District

NASA Astrophysics Data System (ADS)

Zhou, Qiaoying

Academic achievement and student participation in physics are lower than desired. Research has shown that there is a shortage of college students entering science and technology fields such as physics. E-learning may provide the technology-oriented Net Generation learner an option for taking courses such as physics in a course modality with which they are most comfortable thus garnering more participation and higher academic achievement. A quantitative ex-post facto study was performed to compare face-to-face and E-learning modalities on course completion and physics achievement for an entire introductory physics course. The theoretical framework for this study was based on the constructivist theory of education that implies a student-centered learning process. The sample consisted of 116 students enrolled in introductory physics courses at four 2-year community colleges in Texas. Course completion, SAT scores, Force Concept Inventory examination scores, as well as demographic information and employment information were examined. Linear and ordinal multiple regression analysis were used to determine if course modality is predictive of physics achievement while controlling for general scholastic aptitude, current employment, the presence of children in the home, and teacher evaluations. The results showed that students in the E-learning course performed better on the Force Concept Inventory than those in the traditional course both in the multiple regression analysis, beta = .61, p < .001, and in the ordinal regression analysis, Wald(1) = 18.83, p < .001. A chi-square test was used to determine if course completion rates differ between students in the two course modalities. The results showed no difference in course completion rates between students in the two course modalities, chi 2(1, n = 116) = 1.02, p = .312. It was concluded that students in an E-learning course modality had higher physics achievement but were no more likely to complete the introductory physics course than students were in a face-to-face modality. It was recommended that other colleges and universities should develop and test E-learning courses for introductory physics, that larger sample sizes should be used in future studies, and that additional outcome variables including the likelihood that a student chooses physics as a major or the likelihood that a student completes a physics degree should be examined.

Understanding Older Adults' Physical Activity Behavior: A Multi-Theoretical Approach

ERIC Educational Resources Information Center

Grodesky, Janene M.; Kosma, Maria; Solmon, Melinda A.

2006-01-01

Physical inactivity is a health issue with serious consequences for older adults. Investigating physical activity promotion within a multi-theoretical approach may increase the predictive strength of physical activity determinants and facilitate the development and implementation of effective interventions for older adults. This article examines…

Images of Inherited War: Three American Presidents in Vietnam

DTIC Science & Technology

2011-06-01

Dependent Realism to demonstrate how theoretical advances in modern physical science correlate to cognitive theories in International Relations. We...Quantum Physics and Model-Dependent Realism In his book, The Grand Design, theoretical physicist and cosmologist Stephen Hawking draws on theoretical...exhibited wave-like properties and that existing scientific laws could not account for their behavior. Newtonian physics was “built on a framework

Asteroid differentiation - Pyroclastic volcanism to magma oceans

NASA Technical Reports Server (NTRS)

Taylor, G. J.; Keil, Klaus; Mccoy, Timothy; Haack, Henning; Scott, Edward R. D.

1993-01-01

A summary is presented of theoretical and speculative research on the physics of igneous processes involved in asteroid differentiation. Partial melting processes, melt migration, and their products are discussed and explosive volcanism is described. Evidence for the existence of asteroidal magma oceans is considered and processes which may have occurred in these oceans are examined. Synthesis and inferences of asteroid heat sources are discussed under the assumption that asteroids are heated mainly by internal processes and that the role of impact heating is small. Inferences of these results for earth-forming planetesimals are suggested.

Electrostatic atomization--Experiment, theory and industrial applications

NASA Astrophysics Data System (ADS)

Okuda, H.; Kelly, Arnold J.

1996-05-01

Experimental and theoretical research has been initiated at the Princeton Plasma Physics Laboratory on the electrostatic atomization process in collaboration with Charged Injection Corporation. The goal of this collaboration is to set up a comprehensive research and development program on the electrostatic atomization at the Princeton Plasma Physics Laboratory so that both institutions can benefit from the collaboration. Experimental, theoretical and numerical simulation approaches are used for this purpose. An experiment consisting of a capillary sprayer combined with a quadrupole mass filter and a charge detector was installed at the Electrostatic Atomization Laboratory to study fundamental properties of the charged droplets such as the distribution of charges with respect to the droplet radius. In addition, a numerical simulation model is used to study interaction of beam electrons with atmospheric pressure water vapor, supporting an effort to develop an electrostatic water mist fire-fighting nozzle.

State-Transition Structures in Physics and in Computation

NASA Astrophysics Data System (ADS)

Petri, C. A.

1982-12-01

In order to establish close connections between physical and computational processes, it is assumed that the concepts of “state” and of “transition” are acceptable both to physicists and to computer scientists, at least in an informal way. The aim of this paper is to propose formal definitions of state and transition elements on the basis of very low level physical concepts in such a way that (1) all physically possible computations can be described as embedded in physical processes; (2) the computational aspects of physical processes can be described on a well-defined level of abstraction; (3) the gulf between the continuous models of physics and the discrete models of computer science can be bridged by simple mathematical constructs which may be given a physical interpretation; (4) a combinatorial, nonstatistical definition of “information” can be given on low levels of abstraction which may serve as a basis to derive higher-level concepts of information, e.g., by a statistical or probabilistic approach. Conceivable practical consequences are discussed.

Linking theory with qualitative research through study of stroke caregiving families.

PubMed

Pierce, Linda L; Steiner, Victoria; Cervantez Thompson, Teresa L; Friedemann, Marie-Luise

2014-01-01

This theoretical article outlines the deliberate process of applying a qualitative data analysis method rooted in Friedemann's Framework of Systemic Organization through the study of a web-based education and support intervention for stroke caregiving families. Directed by Friedemann's framework, the analytic method involved developing, refining, and using a coding rubric to explore interactive patterns between caregivers and care recipients from this 3-month feasibility study using this education and support intervention. Specifically, data were gathered from the intervention's web-based discussion component between caregivers and the nurse specialist, as well as from telephone caregiver interviews. A theoretical framework guided the process of developing and refining this coding rubric for the purpose of organizing data; but, more importantly, guided the investigators' thought processes, allowing them to extract rich information from the data set, as well as synthesize this information to generate a broad understanding of the caring situation. © 2013 Association of Rehabilitation Nurses.

New phenomena in non-equilibrium quantum physics

NASA Astrophysics Data System (ADS)

Kitagawa, Takuya

From its beginning in the early 20th century, quantum theory has become progressively more important especially due to its contributions to the development of technologies. Quantum mechanics is crucial for current technology such as semiconductors, and also holds promise for future technologies such as superconductors and quantum computing. Despite of the success of quantum theory, its applications have been mostly limited to equilibrium or static systems due to 1. lack of experimental controllability of non-equilibrium quantum systems 2. lack of theoretical frameworks to understand non-equilibrium dynamics. Consequently, physicists have not yet discovered too many interesting phenomena in non-equilibrium quantum systems from both theoretical and experimental point of view and thus, non-equilibrium quantum physics did not attract too much attentions. The situation has recently changed due to the rapid development of experimental techniques in condensed matter as well as cold atom systems, which now enables a better control of non-equilibrium quantum systems. Motivated by this experimental progress, we constructed theoretical frameworks to study three different non-equilibrium regimes of transient dynamics, steady states and periodically drives. These frameworks provide new perspectives for dynamical quantum process, and help to discover new phenomena in these systems. In this thesis, we describe these frameworks through explicit examples and demonstrate their versatility. Some of these theoretical proposals have been realized in experiments, confirming the applicability of the theories to realistic experimental situations. These studies have led to not only the improved fundamental understanding of non-equilibrium processes in quantum systems, but also suggested entirely different venues for developing quantum technologies.