WorldWideScience

Sample records for map commuting patterns

  1. Generalized $ f $-nonexpansive R-subweakly commuting multivalued maps

    Directory of Open Access Journals (Sweden)

    P. Vijayaraju

    2007-12-01

    Full Text Available WWe prove coincidence point theorems for the generalized $ f $-nonexpansive R-subweakly commuting multivalued maps. Our results generalize and extend well known results for noncommuting maps.

  2. Exploratory mapping of commuter flows in England and Wales

    DEFF Research Database (Denmark)

    Nielsen, Thomas Alexander Sick; Hovgesen, Henrik Harder; Lassen, Claus

    2005-01-01

    within England and Wales and in more details around a number of cities. In the city “cases” specific attention is given to the “range of influence” of each metropolitan area, measured through the variation in commute distances and the directionality of commuting. The cities are London, Manchester...... and Birmingham. These are chosen for their size and differences in regional context. In the general analysis – at the country-wide scale - special emphasis is put on deriving a representation of the scale and the corridors of interaction from the relatively disaggregate data. A map of commuter flows in England...

  3. Strong skew commutativity preserving maps on von Neumann algebras

    CERN Document Server

    Qi, Xiaofei

    2012-01-01

    Let ${\\mathcal M}$ be a von Neumann algebra without central summands of type $I_1$. Assume that $\\Phi:{\\mathcal M}\\rightarrow {\\mathcal M}$ is a surjective map. It is shown that $\\Phi$ is strong skew commutativity preserving (that is, satisfies $\\Phi(A)\\Phi(B)-\\Phi(B)\\Phi(A)^*=AB-BA^*$ for all $A,B\\in{\\mathcal M}$) if and only if there exists some self-adjoint element $Z$ in the center of ${\\mathcal M}$ with $Z^2=I$ such that $\\Phi(A)=ZA$ for all $A\\in{\\mathcal M}$. The strong skew commutativity preserving maps on prime involution rings and prime involution algebras are also characterized.

  4. coincidentally commuting mappings in D-metric spaces

    Directory of Open Access Journals (Sweden)

    B. C. Dhage

    2003-01-01

    pairs of a single-valued and a multivalued coincidentally commuting mappings in D-metric spaces satisfying a certain generalized contraction condition. Our result generalizes more than a dozen known fixed-point theorems in D-metric spaces including those of Dhage (2000 and Rhoades (1996.

  5. ON POINTWISE R-SUBWEAKLY COMMUTING MAPS AND BEST APPROXIMATIONS

    Institute of Scientific and Technical Information of China (English)

    F. Akbar; N.Sultana

    2008-01-01

    The main purpose of this paper is to prove some common fixed point theorems for pointwise R-subweakly commuting maps on non-starshaped domains in P-normed spaces and locally convex topological vector spaces.As applications,invariant approximation results ale established.This work provides extension as well as substantial improvement of several results in the existing literature.

  6. Commuting patterns of workers in a village of Barddhaman district, West Bengal

    Directory of Open Access Journals (Sweden)

    Bhaswati Mondal

    2015-06-01

    Full Text Available Commuting helps to keep balance between residence and workplace of workers. With growing accessibility and connectivity, the importance of commuting is increasing all over the world. It is becoming a major substitute to migration. In commute-studies, commute-pattern is an important chapter. It highlights commuters’ directions of movement, distance they cover, modes of transport they use, the time they take to commute, etc. Unlike the urban-based commute pattern, commute pattern in rural areas are relatively an under-researched issue. In fact, traditionally rural people are thought to carry a sedentary lifestyle. Using primary data, this study aims to explore the commute patterns of rural workers located in the village of Gandharbapur of Barddhaman district of West Bengal, India. All the commuters were found to be engaged in non-farm work. Commuters stem from two major groups. One group of commuters is accumulated farm-income induced. They possess sufficient agricultural land. Investing their surplus farm-income, they have established non-farm works. The second group of commuters is poverty-driven. They are landless poor or are marginal farmers and to escape poverty, they have slipped into these works. Located beyond the suburban area (Memari being the nearest town, most commuters commute to nearby rural areas. Due to non-availability of public transport, women commute less than men do. Regular-paid government employees commute longer than other workers commute. The article concludes with a summary of findings and recommendations for further research.

  7. Commute Maps: Separating Slowly Mixing Molecular Configurations for Kinetic Modeling.

    Science.gov (United States)

    Noé, Frank; Banisch, Ralf; Clementi, Cecilia

    2016-11-08

    Identification of the main reaction coordinates and building of kinetic models of macromolecular systems require a way to measure distances between molecular configurations that can distinguish slowly interconverting states. Here we define the commute distance that can be shown to be closely related to the expected commute time needed to go from one configuration to the other, and back. A practical merit of this quantity is that it can be easily approximated from molecular dynamics data sets when an approximation of the Markov operator eigenfunctions is available, which can be achieved by the variational approach to approximate eigenfunctions of Markov operators, also called variational approach of conformation dynamics (VAC) or the time-lagged independent component analysis (TICA). The VAC or TICA components can be scaled such that a so-called commute map is obtained in which Euclidean distance corresponds to the commute distance, and thus kinetic models such as Markov state models can be computed based on Euclidean operations, such as standard clustering. In addition, the distance metric gives rise to a quantity we call total kinetic content, which is an excellent score to rank input feature sets and kinetic model quality.

  8. How do motorways shape commuting patterns?

    DEFF Research Database (Denmark)

    Hovgesen, Henrik Harder; Nielsen, Thomas Alexander Sick

    2004-01-01

    This paper is an offspring from the research project Town, Road and Landscape held by Aalborg University in corporation with the Danish Road Directorate and The Royal Veterinary and Agricultural University. The projects first phase focuses on the effect on the Danish motorway network...... on urbanization and spatial interaction patterns in the last 20 years. This paper presents results on how the building of the motorway network has shaped spatial interactions patterns in Denmark over a ten year period. The question asked is how travel time reductions and changing motorway access is related...

  9. ASYMPTOTIC BEHAVIOR FOR COMMUTATIVE SEMIGROUPS OF ALMOST ASYMPTOTICALLY NONEXPANSIVE TYPE MAPPINGS

    Institute of Scientific and Technical Information of China (English)

    Zeng Luchuan

    2006-01-01

    This article introduces the concept of commutative semigroups of almost asymptotically nonexpansive-type mappings in a Ban ach space X which has the Opial property and whose norm is UKK, and establishes the weak convergence theorems for almostorbits of this class of commutative semigroups. The author improves, extends and develops some recent and earlier results.

  10. Linear Commuting Maps on Parab olic Subalgebras of Finite-dimensional Simple Lie Algebras

    Institute of Scientific and Technical Information of China (English)

    CHEN Zheng-xin; WANG Bing

    2014-01-01

    A map ϕ on a Lie algebra g is called to be commuting if [ϕ(x), x] = 0 for all x∈g. Let L be a finite-dimensional simple Lie algebra over an algebraically closed field F of characteristic 0, P a parabolic subalgebra of L. In this paper, we prove that a linear mapϕon P is commuting if and only ifϕis a scalar multiplication map on P .

  11. Changes to urban form and commuting patterns: trends in two Danish city regions

    DEFF Research Database (Denmark)

    Nielsen, Thomas Alexander Sick

    2015-01-01

    towards more balanced development. The increasing size of the main node in the PUR is the only deviation from the general trend. The general tendency towards a more polycentric regional structure was most marked in changing interaction and commuting patterns. Inter-urban commuting increased, while intra......-urban commuting decreased, leading to dispersion of commuters and a rapid increase in commuting across the region. Commuting distances were shortest in the polycentric region, but it also had the highest growth rates. In both regions, the balancing trend leads to a dispersal of commuting demand over...... an increasingly complex web of origins and destination nodes. This tendency compels us to question whether people’s choice of residence is becoming increasingly irrelevant to their place of work. In relation to polycentricity and sustainability, this calls into question the degree to which proximity can...

  12. Commuting Pattern with Park-and-Ride Option for Heterogeneous Commuters

    Directory of Open Access Journals (Sweden)

    Chengjuan Zhu

    2013-01-01

    Full Text Available We study the effect of the parking on heterogeneous commuters' travel choice in a competitive transportation system which consists of a subway and a parallel road with a bottleneck of limited service capacity. Every morning, commuters either use their private cars only or drive their cars to the bottleneck, park there, and then take the subway to the destination. Considering the effects caused by body congestion in carriage and the parking fees, we developed a bottleneck model to describe the commuters' travel choice. There exist several types of equilibrium that corresponds to user equilibrium. We investigated the influence of the capacity of the bottleneck and the total travel demand on the travel behaviors and on the total social cost. It is shown that there exists a scheme with suitable subway fare and parking fees to implement the minimum total social cost.

  13. Quantization maps, algebra representation, and non-commutative Fourier transform for Lie groups

    Energy Technology Data Exchange (ETDEWEB)

    Guedes, Carlos; Oriti, Daniele [Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Am Mühlenberg 1, 14476 Potsdam (Germany); Raasakka, Matti [Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Am Mühlenberg 1, 14476 Potsdam (Germany); LIPN, Institut Galilée, Université Paris-Nord, 99, av. Clement, 93430 Villetaneuse (France)

    2013-08-15

    The phase space given by the cotangent bundle of a Lie group appears in the context of several models for physical systems. A representation for the quantum system in terms of non-commutative functions on the (dual) Lie algebra, and a generalized notion of (non-commutative) Fourier transform, different from standard harmonic analysis, has been recently developed, and found several applications, especially in the quantum gravity literature. We show that this algebra representation can be defined on the sole basis of a quantization map of the classical Poisson algebra, and identify the conditions for its existence. In particular, the corresponding non-commutative star-product carried by this representation is obtained directly from the quantization map via deformation quantization. We then clarify under which conditions a unitary intertwiner between such algebra representation and the usual group representation can be constructed giving rise to the non-commutative plane waves and consequently, the non-commutative Fourier transform. The compact groups U(1) and SU(2) are considered for different choices of quantization maps, such as the symmetric and the Duflo map, and we exhibit the corresponding star-products, algebra representations, and non-commutative plane waves.

  14. Strong ergodic theorem for commutative semigroup of non-Lipschitzian mappings in multi-Banach space

    Indian Academy of Sciences (India)

    M AZHINI; H M KENARI; R SAADATI

    2017-09-01

    Let $C$ be a bounded closed convex subset of a uniformly convex multi-Banach space $X$ and let $\\Im_{j}$ = ${T_{j} (t) : t \\in G}$ be a commutative semigroup of asymptotically nonexpansive in the intermediate mapping from $C$ into itself. In this paper, we prove the strong mean ergodic convergence theorem for the almost-orbit of $\\Im$. Our results extend and unify many previously known results especially (Dong et al. On the strong ergodic theorem for commutative semigroup of non-Lipschitzian mappings in Banach space, preprint).

  15. On Some Isomorphisms between Bounded Linear Maps and Non-Commutative Lp-Spaces

    Directory of Open Access Journals (Sweden)

    E. J. Atto

    2014-04-01

    Full Text Available We define a particular space of bounded linear maps using a Von Neumann algebra and some operator spaces. By this, we prove some isomorphisms, and using interpolation in some particular cases, we get analogue of non-commutative Lp spaces.

  16. Coincidence and fixed point results for non-commuting maps

    Directory of Open Access Journals (Sweden)

    Abdul Latif

    2008-06-01

    Full Text Available In the setting of Banach spaces, some results on the existence of coincidence and common fixed points for single-valued and multivalued non-commuting maps with and without contractive type conditions are obtained.

  17. Modeling commuting patterns in a multi-regional input-output framework: impacts of an `urban re-centralization' scenario

    Science.gov (United States)

    Ferreira, J.-P.; Ramos, P.; Cruz, L.; Barata, E.

    2017-10-01

    The paper suggests a modeling approach for assessing economic and social impacts of changes in urban forms and commuting patterns that extends a multi-regional input-output framework by incorporating a set of commuting-related consequences. The Lisbon Metropolitan Area case with an urban re-centralization scenario is used as an example to illustrate the relevance of this modeling approach for analyzing commuting-related changes in regional income distribution on the one side and in household consumption structures on the other.

  18. Urban expansion and transportation : the impact of urban form on commuting patterns on the city fringe of Beijing

    NARCIS (Netherlands)

    Zhao, Pengjun; Lue, Bin; de Roo, Gert

    2010-01-01

    A key issue in the development of China's growing megacities in the transport-related environmental costs due to rapid urban expansion. In light of this issue, the authors examine the impact of urban form on commuting patterns on the city fringe of Beijing. Based on household-survey data, the

  19. Chern-Simons in the Seiberg-Witten map for non-commutative Abelian gauge theories in 4D

    CERN Document Server

    Picariello, M; Sorella, S P; Picariello, Marco; Quadri, Andrea; Sorella, Silvio P.

    2002-01-01

    A cohomological BRST characterization of the Seiberg-Witten (SW) map is given. We prove that the coefficients of the SW map can be identified with elements of the cohomology of the BRST operator modulo a total derivative. As an example, it will be illustrated how the first coefficients of the SW map can be written in terms of the Chern-Simons three form. This suggests a deep topological and geometrical origin of the SW map. The existence of the map for both Abelian and non-Abelian case is discussed. By using a recursive argument and the associativity of the $\\star$-product, we shall be able to prove that the Wess-Zumino consistency condition for non-commutative BRST transformations is fulfilled. The recipe of obtaining an explicit solution by use of the homotopy operator is briefly reviewed in the Abelian case.

  20. Software patterns, knowledge maps, and domain analysis

    CERN Document Server

    Fayad, Mohamed E; Hegde, Srikanth GK; Basia, Anshu; Vakil, Ashka

    2014-01-01

    Preface AcknowledgmentsAuthors INTRODUCTIONAn Overview of Knowledge MapsIntroduction: Key Concepts-Software Stable Models, Knowledge Maps, Pattern Language, Goals, Capabilities (Enduring Business Themes + Business Objects) The Motivation The Problem The Objectives Overview of Software Stability Concepts Overview of Knowledge Maps Pattern Languages versus Knowledge Maps: A Brief ComparisonThe Solution Knowledge Maps Methodology or Concurrent Software Development ModelWhy Knowledge Maps? Research Methodology Undertaken Research Verification and Validation The Stratification of This Book Summary

  1. Commutative Algebra

    CERN Document Server

    Fontana, Marco; Olberding, Bruce; Swanson, Irena

    2011-01-01

    Commutative algebra is a rapidly growing subject that is developing in many different directions. This volume presents several of the most recent results from various areas related to both Noetherian and non-Noetherian commutative algebra. This volume contains a collection of invited survey articles by some of the leading experts in the field. The authors of these chapters have been carefully selected for their important contributions to an area of commutative-algebraic research. Some topics presented in the volume include: generalizations of cyclic modules, zero divisor graphs, class semigrou

  2. Making almost commuting matrices commute

    Energy Technology Data Exchange (ETDEWEB)

    Hastings, Matthew B [Los Alamos National Laboratory

    2008-01-01

    Suppose two Hermitian matrices A, B almost commute ({parallel}[A,B]{parallel} {<=} {delta}). Are they close to a commuting pair of Hermitian matrices, A', B', with {parallel}A-A'{parallel},{parallel}B-B'{parallel} {<=} {epsilon}? A theorem of H. Lin shows that this is uniformly true, in that for every {epsilon} > 0 there exists a {delta} > 0, independent of the size N of the matrices, for which almost commuting implies being close to a commuting pair. However, this theorem does not specifiy how {delta} depends on {epsilon}. We give uniform bounds relating {delta} and {epsilon}. The proof is constructive, giving an explicit algorithm to construct A' and B'. We provide tighter bounds in the case of block tridiagonal and tridiagnonal matrices. Within the context of quantum measurement, this implies an algorithm to construct a basis in which we can make a projective measurement that approximately measures two approximately commuting operators simultaneously. Finally, we comment briefly on the case of approximately measuring three or more approximately commuting operators using POVMs (positive operator-valued measures) instead of projective measurements.

  3. Computational linear and commutative algebra

    CERN Document Server

    Kreuzer, Martin

    2016-01-01

    This book combines, in a novel and general way, an extensive development of the theory of families of commuting matrices with applications to zero-dimensional commutative rings, primary decompositions and polynomial system solving. It integrates the Linear Algebra of the Third Millennium, developed exclusively here, with classical algorithmic and algebraic techniques. Even the experienced reader will be pleasantly surprised to discover new and unexpected aspects in a variety of subjects including eigenvalues and eigenspaces of linear maps, joint eigenspaces of commuting families of endomorphisms, multiplication maps of zero-dimensional affine algebras, computation of primary decompositions and maximal ideals, and solution of polynomial systems. This book completes a trilogy initiated by the uncharacteristically witty books Computational Commutative Algebra 1 and 2 by the same authors. The material treated here is not available in book form, and much of it is not available at all. The authors continue to prese...

  4. Relations between Non-Commutative and Commutative Spacetime

    CERN Document Server

    Tezuka, K I

    2001-01-01

    Spacetime non-commutativity appears in string theory. In this paper, the non-commutativity in string theory is reviewed. At first we review that a Dp-brane is equivalent to a configuration of infinitely many D($p-2$)-branes. If we consider the worldvolume as that of the Dp-brane, coordinates of the Dp-brane is commutative. On the other hand if we deal with the worldvolume as that of the D($p-2$)-branes, since coordinates of many D-branes are promoted to matrices the worldvolume theory is non-commutative one. Next we see that using a point splitting reguralization gives a non-commutative D-brane, and a non-commutative gauge field can be rewritten in terms of an ordinary gauge field. The transformation is called the Seiberg-Witten map. And we introduce second class constraints as boundary conditions of an open string. Since Neumann and Dirichlet boundary conditions are mixed in the constraints when the open string is coupled to a NS B field, the end points of the open string is non-commutative.

  5. Mapping the Communication Patterns of Adolescents

    Science.gov (United States)

    West, Lloyd W.

    1974-01-01

    The current academic interest in interpersonal communication is noted and a rationale and technique for mapping the self-disclosure patterns of adolescents is presented. An attempt is made to link the study of interpersonal communication to the mainstream of the ecological systems approach to the behavioral sciences. (Author)

  6. Inferring Passenger Type from Commuter Eigentravel Matrices

    OpenAIRE

    Legara, Erika Fille; Monterola, Christopher

    2015-01-01

    A sufficient knowledge of the demographics of a commuting public is essential in formulating and implementing more targeted transportation policies, as commuters exhibit different ways of traveling. With the advent of the Automated Fare Collection system (AFC), probing the travel patterns of commuters has become less invasive and more accessible. Consequently, numerous transport studies related to human mobility have shown that these observed patterns allow one to pair individuals with locati...

  7. Multifractal Simulation of Geochemical Map Patterns

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using a simple multifractal model based on the model De Wijs, various geochemical map patterns for element concentration values are being simulated. Each pattern is self-similar on the average in that a similar pattern can be derived by application of the multiplicative cascade model used to any small subarea on the pattern. In other experiments, the original, self-similar pattern is distorted by superimposing a 2-dimensional trend pattern and by mixing it with a constant concentration value model. It is investigated how such distortions change the multifractal spectrum estimated by means of the 3-step method of moments. Discrete and continuous frequency distribution models are derived for patterns that satisfy the model of De Wijs. These simulated patterns satisfy a discrete frequency distribution model that as upper bound has a continuous frequency distribution to which it approaches in form when the subdivisions of the multiplicative cascade model are repeated indefinitely. This limiting distribution is lognormal in the center and has Pareto tails. Potentially, this approach has important implications in mineral and oil resource evaluation.

  8. Landscape patterns from mathematical morphology on maps with contagion

    Science.gov (United States)

    Kurt Riitters; Peter Vogt; Pierre Soille; Christine Estreguil

    2009-01-01

    The perceived realism of simulated maps with contagion (spatial autocorrelation) has led to their use for comparing landscape pattern metrics and as habitat maps for modeling organism movement across landscapes. The objective of this study was to conduct a neutral model analysis of pattern metrics defined by morphological spatial pattern analysis (MSPA) on maps with...

  9. Inferring Passenger Type from Commuter Eigentravel Matrices

    CERN Document Server

    Legara, Erika Fille

    2015-01-01

    A sufficient knowledge of the demographics of a commuting public is essential in formulating and implementing more targeted transportation policies, as commuters exhibit different ways of traveling. With the advent of the Automated Fare Collection system (AFC), probing the travel patterns of commuters has become less invasive and more accessible. Consequently, numerous transport studies related to human mobility have shown that these observed patterns allow one to pair individuals with locations and/or activities at certain times of the day. However, classifying commuters using their travel signatures is yet to be thoroughly examined. Here, we contribute to the literature by demonstrating a procedure to characterize passenger types (Adult, Child/Student, and Senior Citizen) based on their three-month travel patterns taken from a smart fare card system. We first establish a method to construct distinct commuter matrices, which we refer to as eigentravel matrices, that capture the characteristic travel routines...

  10. On CNC Commuting Contractive Tuples

    Indian Academy of Sciences (India)

    T Bhattacharyya; J Eschmeier; J Sarkar

    2006-08-01

    The characteristic function has been an important tool for studying completely non-unitary contractions on Hilbert spaces. In this note, we consider completely non-coisometric contractive tuples of commuting operators on a Hilbert space $\\mathcal{H}$. We show that the characteristic function, which is now an operator-valued analytic function on the open Euclidean unit ball in $\\mathbb{C}^n$, is a complete unitary invariant for such a tuple. We prove that the characteristic function satisfies a natural transformation law under biholomorphic mappings of the unit ball. We also characterize all operator-valued analytic functions which arise as characteristic functions of pure commuting contractive tuples.

  11. Distributions of order patterns of interval maps

    CERN Document Server

    Abrams, Aaron; Landau, Henry; Landau, Zeph; Pommersheim, James

    2010-01-01

    A permutation $\\sigma$ describing the relative orders of the first $n$ iterates of a point $x$ under a self-map $f$ of the interval $I=[0,1]$ is called an \\emph{order pattern}. For fixed $f$ and $n$, measuring the points $x\\in I$ (according to Lebesgue measure) that generate the order pattern $\\sigma$ gives a probability distribution $\\mu_n(f)$ on the set of length $n$ permutations. We study the distributions that arise this way for various classes of functions $f$. Our main results treat the class of measure preserving functions. We obtain an exact description of the set of realizable distributions in this case: for each $n$ this set is a union of open faces of the polytope of flows on a certain digraph, and a simple combinatorial criterion determines which faces are included. We also show that for general $f$, apart from an obvious compatibility condition, there is no restriction on the sequence $\\{\\mu_n(f)\\}$ for $n=1,2,...$. In addition, we give a necessary condition for $f$ to have \\emph{finite exclusion...

  12. Inductively commutated coilguns

    Energy Technology Data Exchange (ETDEWEB)

    Mongeau, P.P. (EML Research, Inc., Hudson, MA (US))

    1991-01-01

    In this paper the concept and relevance of power factor is presented in regards to high performance launchers. As the scale of launchers grows and as efforts to improve efficiency continue power factor considerations will become crucial in engineering design and ultimate launcher performance limits. The use of motion induced commutation to improve the power factor are discussed. Various approaches to inductive commutation are presented, including: the brush-commutated 9 MJ Coilgun, the solid state-switched coilgun and the quenchgun.

  13. Inductively commutated coilguns

    Science.gov (United States)

    Mongeau, Peter P.

    1991-01-01

    The concept and relevance of power factor is presented in the context of high-performance launchers. As the scale of launchers grows and efforts to improve efficiency continue, power factor considerations will become crucial in engineering design and ultimate launcher performance limits. The use of motion-induced commutation to improve the power factor are discussed. Various approaches to inductive commutation are presented, including the brush-commutated 9-MJ coilgun, the solid state-switched coilgun, and the quenchgun.

  14. Functional Polycentrism and Urban Network Development in the Greater South East UK: Evidence from Commuting Patterns, 1981-2001

    NARCIS (Netherlands)

    B. de Goei (Bastiaan); M.J. Burger (Martijn); F.G. van Oort (Frank); M. Kitson (Michael)

    2009-01-01

    textabstractIn contemporary literature on changing urban systems, it is often argued that the traditional central place conceptualisation is outdated and should be replaced by a network view that emphasises the increasing criss-crossing pattern of interdependencies between spatial units. This paper

  15. Scalar fields in a non-commutative space

    CERN Document Server

    Bietenholz, Wolfgang; Mejía-Díaz, Héctor; Panero, Marco

    2014-01-01

    We discuss the lambda phi**4 model in 2- and 3-dimensional non-commutative spaces. The mapping onto a Hermitian matrix model enables its non-perturbative investigation by Monte Carlo simulations. The numerical results reveal a phase where stripe patterns dominate. In d=3 we show that in this phase the dispersion relation is deformed in the IR regime, in agreement with the property of UV/IR mixing. This "striped phase" also occurs in d=2. For both dimensions we provide evidence that it persists in the simultaneous limit to the continuum and to infinite volume ("Double Scaling Limit"). This implies the spontaneous breaking of translation symmetry.

  16. Wages and commuting

    DEFF Research Database (Denmark)

    Mulalic, Ismir; Ommeren, Jos N. van; Pilegaard, Ninette

    2011-01-01

    income tax reductions associated with commuting do not apply, one kilometre increase in commuting distance induces a wage increase of about 0.42%, suggesting an hourly compensation of about half of the hourly net wage. Our findings are consistent with wage bargaining theory and suggest a bargaining power...

  17. Wages and commuting

    DEFF Research Database (Denmark)

    Mulalic, Ismir; Ommeren, Jos N. van; Pilegaard, Ninette

    2011-01-01

    We examine the causal effect of commuting distance on workers' wages in a quasi-natural experiments setting using information on all workers in Denmark. We account for endogeneity of distance by using changes in distance that are due to firms’ relocations. For the range of commuting distances whe...

  18. Gaussian processes in non-commutative probability theory

    NARCIS (Netherlands)

    Guţǎ, M.I.

    2002-01-01

    The generalisation of the notion of Gaussian processes from probability theory is investigated in the context of non-commutative probability theory. A non-commutative Gaussian process is viewed as a linear map from an infinite dimensional (real) Hilbert space into an algebra with involution and a po

  19. Mapping global diversity patterns for migratory birds.

    Directory of Open Access Journals (Sweden)

    Marius Somveille

    Full Text Available Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world's birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective.

  20. Mapping global diversity patterns for migratory birds.

    Science.gov (United States)

    Somveille, Marius; Manica, Andrea; Butchart, Stuart H M; Rodrigues, Ana S L

    2013-01-01

    Nearly one in five bird species has separate breeding and overwintering distributions, and the regular migrations of these species cause a substantial seasonal redistribution of avian diversity across the world. However, despite its ecological importance, bird migration has been largely ignored in studies of global avian biodiversity, with few studies having addressed it from a macroecological perspective. Here, we analyse a dataset on the global distribution of the world's birds in order to examine global spatial patterns in the diversity of migratory species, including: the seasonal variation in overall species diversity due to migration; the contribution of migratory birds to local bird diversity; and the distribution of narrow-range and threatened migratory birds. Our analyses reveal a striking asymmetry between the Northern and Southern hemispheres, evident in all of the patterns investigated. The highest migratory bird diversity was found in the Northern Hemisphere, with high inter-continental turnover in species composition between breeding and non-breeding seasons, and extensive regions (at high latitudes) where migratory birds constitute the majority of the local avifauna. Threatened migratory birds are concentrated mainly in Central and Southern Asia, whereas narrow-range migratory species are mainly found in Central America, the Himalayas and Patagonia. Overall, global patterns in the diversity of migratory birds indicate that bird migration is mainly a Northern Hemisphere phenomenon. The asymmetry between the Northern and Southern hemispheres could not have easily been predicted from the combined results of regional scale studies, highlighting the importance of a global perspective.

  1. The yoga of commutators

    CERN Document Server

    Hazrat, R; Vavilov, N A; Zhang, Z

    2011-01-01

    In the present paper we discuss some recent versions of localisation methods for calculations in the groups of points of algebraic-like and classical-like groups. Namely, we describe relative localisation, universal localisation, and enhanced versions of localisation-completion. Apart from the general strategic description of these methods, we state some typical technical results of the conjugation calculus and the commutator calculus. Also, we state several recent results obtained therewith, such as relative standard commutator formulae, bounded width of commutators, with respect to the elementary generators, and nilpotent filtrations of congruence subgroups. Overall, this shows that localisation methods can be much more efficient, than expected.

  2. Envelopes of Commutative Rings

    Institute of Scientific and Technical Information of China (English)

    Rafael PARRA; Manuel SAOR(I)N

    2012-01-01

    Given a significative class F of commutative rings,we study the precise conditions under which a commutative ring R has an F-envelope.A full answer is obtained when.F is the class of fields,semisimple commutative rings or integral domains.When F is the class of Noetherian rings,we give a full answer when the Krull dimension of R is zero and when the envelope is required to be epimorphic.The general problem is reduced to identifying the class of non-Noetherian rings having a monomorphic Noetherian envelope,which we conjecture is the empty class.

  3. Commuter Survey-2014

    Data.gov (United States)

    US Agency for International Development — This dataset is the USAID portion of a larger dataset developed by OMB to better understand and to quanity the carbon footprint of the daily commute of government...

  4. Commutation and Darboux transformation

    Indian Academy of Sciences (India)

    M V Prabhakar; H Bhate

    2015-11-01

    In this paper we show that the Darboux transformation for a large class of nonlinear evolution equations arises due to factorization and commutation. The factorization and commutation has been pointed out earlier for Schrödinger operator. We show that it extends to a large class of nonlinear differential equations which admit Lax pairs including Boussinesq, Davey–Stewartson, Bogoyavlensky–Schiff and -wave interaction equation.

  5. Associativity as Commutativity

    OpenAIRE

    Dosen, K.; Petric, Z.

    2005-01-01

    It is shown that coherence conditions for monoidal categories concerning associativity are analogous to coherence conditions for symmetric or braided strictly monoidal categories, where associativity arrows are identities. Mac Lane's pentagonal coherence condition for associativity is decomposed into conditions concerning commutativity, among which we have a condition analogous to naturality and a degenerate case of Mac Lane's hexagonal condition for commutativity. This decomposition is analo...

  6. Computational commutative and non-commutative algebraic geometry

    CERN Document Server

    Cojocaru, S; Ufnarovski, V

    2005-01-01

    This publication gives a good insight in the interplay between commutative and non-commutative algebraic geometry. The theoretical and computational aspects are the central theme in this study. The topic is looked at from different perspectives in over 20 lecture reports. It emphasizes the current trends in commutative and non-commutative algebraic geometry and algebra. The contributors to this publication present the most recent and state-of-the-art progresses which reflect the topic discussed in this publication. Both researchers and graduate students will find this book a good source of information on commutative and non-commutative algebraic geometry.

  7. Quantifying leaf venation patterns: two-dimensional maps.

    Science.gov (United States)

    Rolland-Lagan, Anne-Gaëlle; Amin, Mira; Pakulska, Malgosia

    2009-01-01

    The leaf vasculature plays crucial roles in transport and mechanical support. Understanding how vein patterns develop and what underlies pattern variation between species has many implications from both physiological and evolutionary perspectives. We developed a method for extracting spatial vein pattern data from leaf images, such as vein densities and also the sizes and shapes of the vein reticulations. We used this method to quantify leaf venation patterns of the first rosette leaf of Arabidopsis thaliana throughout a series of developmental stages. In particular, we characterized the size and shape of vein network areoles (loops), which enlarge and are split by new veins as a leaf develops. Pattern parameters varied in time and space. In particular, we observed a distal to proximal gradient in loop shape (length/width ratio) which varied over time, and a margin-to-center gradient in loop sizes. Quantitative analyses of vein patterns at the tissue level provide a two-way link between theoretical models of patterning and molecular experimental work to further explore patterning mechanisms during development. Such analyses could also be used to investigate the effect of environmental factors on vein patterns, or to compare venation patterns from different species for evolutionary studies. The method also provides a framework for gathering and overlaying two-dimensional maps of point, line and surface morphological data.

  8. Commuting Dual Toeplitz Operators on the Polydisk

    Institute of Scientific and Technical Information of China (English)

    Yu Feng LU; Shu Xia SHANG

    2007-01-01

    On the polydisk, the commutativity of dual Toeplitz operators is studied. We obtain characterizations of commuting dual Toeplitz operators, essentially commuting dual Toeplitz operators and essentially semi-commuting dual Toeplitz operators.

  9. Engineering antenna radiation patterns via quasi-conformal mappings.

    Science.gov (United States)

    García-Meca, Carlos; Martínez, Alejandro; Leonhardt, Ulf

    2011-11-21

    We use a combination of conformal and quasi-conformal mappings to engineer isotropic electromagnetic devices that modify the omnidirectional radiation pattern of a point source. For TE waves, the designed devices are also non-magnetic. The flexibility offered by the proposed method is much higher than that achieved with conformal mappings. As a result, it is shown that complex radiation patterns can be achieved, which can combine high directivity in a desired number of arbitrary directions and isotropic radiation in other specified angular ranges. In addition, this technique enables us to control the power radiated in each direction to a certain extent. The obtained results are valid for any part of the spectrum. The potential of this method is illustrated with some examples. Finally, we study the frequency dependence of the considered devices and propose a practical dielectric implementation.

  10. Active commuting to school

    Science.gov (United States)

    Declines in physical activity levels have coincided with increasing rates of obesity in children. This is problematic because physical activity has been shown to attenuate weight gain in children. Active commuting to school is one way of increasing children's physical activity. However, given the hi...

  11. Workshop on Commutative Algebra

    CERN Document Server

    Simis, Aron

    1990-01-01

    The central theme of this volume is commutative algebra, with emphasis on special graded algebras, which are increasingly of interest in problems of algebraic geometry, combinatorics and computer algebra. Most of the papers have partly survey character, but are research-oriented, aiming at classification and structural results.

  12. Categories and Commutative Algebra

    CERN Document Server

    Salmon, P

    2011-01-01

    L. Badescu: Sur certaines singularites des varietes algebriques.- D.A. Buchsbaum: Homological and commutative algebra.- S. Greco: Anelli Henseliani.- C. Lair: Morphismes et structures algebriques.- B.A. Mitchell: Introduction to category theory and homological algebra.- R. Rivet: Anneaux de series formelles et anneaux henseliens.- P. Salmon: Applicazioni della K-teoria all'algebra commutativa.- M. Tierney: Axiomatic sheaf theory: some constructions and applications.- C.B. Winters: An elementary lecture on algebraic spaces.

  13. Planar maps, circle patterns and 2d gravity

    CERN Document Server

    David, Francois

    2013-01-01

    Via circle pattern techniques, random planar triangulations (with angle variables) are mapped onto Delaunay triangulations in the complex plane. The uniform measure on triangulations is mapped onto a conformally invariant spatial point process. We show that this measure can be expressed as: (1) a sum over 3-spanning-trees partitions of the edges of the Delaunay triangulations; (2) the volume form of a K\\"ahler metric over the space of Delaunay triangulations, whose prepotential has a simple formulation in term of ideal tessellations of the 3d hyperbolic space; (3) a discretized version (involving finite difference complex derivative operators) of Polyakov's conformal Fadeev-Popov determinant in 2d gravity; (4) a combination of Chern classes, thus also establishing a link with topological 2d gravity.

  14. Mapping Snow Cover Loss Patterns in the Western United States

    Science.gov (United States)

    Moore, C.; Kampf, S. K.; Richer, E.; Stone, B.

    2011-12-01

    Cara Moore, Stephanie Kampf, Eric Richer, Brandon Stone Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO 80523-1499 The Western United States depends on snowmelt to provide water for industrial, municipal, and agricultural needs. Some areas in this region have observed an increase in the proportion of precipitation falling as rain rather than snow in response to climate warming, a trend that can alter the timing and magnitude of runoff. Transitional snow zones, which lie between lower elevation intermittent snowpack and higher elevation persistent snowpack, may be particularly sensitive to changing climate conditions. Snow covered area is an easily obtainable measurement that can help identify the locations and elevations of these transitional snow zones. The purpose of this study is to improve the understanding of snowpack characteristics in the Western U.S. by mapping snow cover loss patterns using the Moderate-Resolution Imaging Spectroradiometer (MODIS) snow covered area (SCA) product. Snow cover loss patterns can be difficult to compare objectively between regions because spring snow storms lead to abrupt increases and decreases in SCA. Therefore, we develop a curve-fitting snow cover depletion model (SCoDMod) used to derive standardized snow cover loss curves. We fit the model to snow cover patterns within 100m elevation zones from January 1st until July 19th for each USGS eight digit hydrologic unit in the Western US. We use the model to identify 11 year (2000-2010) average snow cover loss patterns and compare those patterns to snow cover loss behavior in wet and dry years. Model results give maps of average SCA in the Western United States on the first of the month from January to July, as well as maps of the date of SCA loss to 75% (Q75), 50% (Q50), and 25% (Q25) SCA. Results show that the Cascade, Sierra Nevada, and Rocky mountains from Colorado northward retain >90% SCA until March, whereas most parts of lower elevation

  15. On the commutator length of a Dehn twist

    CERN Document Server

    Szepietowski, Blazej

    2010-01-01

    We show that on a nonorientable surface of genus at least 7 any power of a Dehn twist is equal to a single commutator in the mapping class group and the same is true, under additional assumptions, for the twist subgroup, and also for the extended mapping class group of an orientable surface of genus at least 3.

  16. Radar channel balancing with commutation

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2014-02-01

    When multiple channels are employed in a pulse-Doppler radar, achieving and maintaining balance between the channels is problematic. In some circumstances the channels may be commutated to achieve adequate balance. Commutation is the switching, trading, toggling, or multiplexing of the channels between signal paths. Commutation allows modulating the imbalance energy away from the balanced energy in Doppler, where it can be mitigated with filtering.

  17. Mapping Deforestation and Forest Degradation Patterns in Western Himalaya, Pakistan

    Directory of Open Access Journals (Sweden)

    Faisal Mueen Qamer

    2016-05-01

    Full Text Available The Himalayan mountain forest ecosystem has been degrading since the British ruled the area in the 1850s. Local understanding of the patterns and processes of degradation is desperately required to devise management strategies to halt this degradation and provide long-term sustainability. This work comprises a satellite image based study in combination with national expert validation to generate sub-district level statistics for forest cover over the Western Himalaya, Pakistan, which accounts for approximately 67% of the total forest cover of the country. The time series of forest cover maps (1990, 2000, 2010 reveal extensive deforestation in the area. Indeed, approximately 170,684 ha of forest has been lost, which amounts to 0.38% per year clear cut or severely degraded during the last 20 years. A significant increase in the rate of deforestation is observed in the second half of the study period, where much of the loss occurs at the western borders along with Afghanistan. The current study is the first systematic and comprehensive effort to map changes to forest cover in Northern Pakistan. Deforestation hotspots identified at the sub-district level provide important insight into deforestation patterns, which may facilitate the development of appropriate forest conservation and management strategies in the country.

  18. Mapping spatial patterns of people's risk perception of landslides

    Science.gov (United States)

    Kofler, Christian; Pedoth, Lydia; Elzbieta Stawinoga, Agnieszka; Schneiderbauer, Stefan

    2016-04-01

    The resilience of communities against natural hazards is largely influenced by how the individuals perceive risk. A good understanding of people's risk perception, awareness and hazard knowledge is crucial for developing and improving risk management and communication strategies between authorities and the affected population. A lot of research has been done in investigating the social aspects of risks to natural hazards by means of interviews or questionnaires. However, there is still a lack of research in the investigation of the influence of the spatial distance to a hazard event on peoples risk perception. While the spatial dimension of a natural hazard event is always assessed in works with a natural science approach, it is often neglected in works on social aspects of natural hazards. In the present study, we aimed to overcome these gaps by combining methods from different disciplines and assessing and mapping the spatial pattern of risk perception through multivariate statistical approaches based on empirical data from questionnaires. We will present results from a case study carried out in Badia, located in the Province of South Tyrol- Italy, where in December 2012 a landslide destroyed four residential buildings and led to the evacuation of 36 people. By means of questionnaires distributed to all adults living in the case study area we assessed people's risk perception and asked respondents to allocate their place of residence on a map of the case study area subdivided in 7 zones. Based on the data of the questionnaire results we developed a risk perception factor in order to express various assessed aspects linked to risk perception with one metric. We analyzed and mapped this factor according to the different zones reflecting the spatial distance to the event. Furthermore, a cluster analysis identified various risk behavior profiles within the population. We also investigated the spatial patterns of these risk profiles. We revealed that the residential

  19. Temporal Analysis of Activity Patterns of Editors in Collaborative Mapping Project of OpenStreetMap

    CERN Document Server

    Yasseri, Taha; Mashhadi, Afra

    2013-01-01

    In the recent years Wikis have become an attractive platform for social studies of the human behaviour. Containing millions records of edits across the globe, collaborative systems such as Wikipedia have allowed researchers to gain a better understanding of editors participation and their activity patterns. However, contributions made to Geo-wikis_wiki-based collaborative mapping projects_ differ from systems such as Wikipedia in a fundamental way due to spatial dimension of the content that limits the contributors to a set of those who posses local knowledge about a specific area and therefore cross-platform studies and comparisons are required to build a comprehensive image of online open collaboration phenomena. In this work, we study the temporal behavioural pattern of OpenStreetMap editors, a successful example of geo-wiki, for two European capital cities. We categorise different type of temporal patterns and report on the historical trend within a period of 7 years of the project age. We also draw a com...

  20. Job search and commuting time

    NARCIS (Netherlands)

    Gorter, C.; Berg, van den G.J.

    1996-01-01

    We structurally analyze a job search model for unemployed individuals that allows jobs to have different wage/commuting-time combinations. Thestructural parameter of interest is the willingness to pay for commuting time. We use a unique dataset containing subjective responses on the optimalsearch st

  1. Six Lectures on Commutative Algebra

    CERN Document Server

    Elias, J; Miro-Roig, Rosa Maria; Zarzuela, Santiago

    2009-01-01

    Interest in commutative algebra has surged over the years. In order to survey and highlight the developments in this rapidly expanding field, the Centre de Recerca Matematica in Bellaterra organized a ten-days Summer School on Commutative Algebra in 1996. This title offers a synthesis of the lectures presented at the Summer School

  2. Pattern formation and firing synchronization in networks of map neurons

    Energy Technology Data Exchange (ETDEWEB)

    Wang Qingyun [State Key Laboratory for Turbulence and Complex Systems, Department of Mechanics and Aerospace Engineering, College of Engineering, Peking University, Beijing 100871 (China); Duan Zhisheng [State Key Laboratory for Turbulence and Complex Systems, Department of Mechanics and Aerospace Engineering, College of Engineering, Peking University, Beijing 100871 (China); Huang Lin [State Key Laboratory for Turbulence and Complex Systems, Department of Mechanics and Aerospace Engineering, College of Engineering, Peking University, Beijing 100871 (China); Chen Guanrong [Department of Electronic Engineering, City University of Hong Kong, Hong Kong (China); Lu Qishao [School of Science, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China)

    2007-10-15

    Patterns and collective phenomena such as firing synchronization are studied in networks of nonhomogeneous oscillatory neurons and mixtures of oscillatory and excitable neurons, with dynamics of each neuron described by a two-dimensional (2D) Rulkov map neuron. It is shown that as the coupling strength is increased, typical patterns emerge spatially, which propagate through the networks in the form of beautiful target waves or parallel ones depending on the size of networks. Furthermore, we investigate the transitions of firing synchronization characterized by the rate of firing when the coupling strength is increased. It is found that there exists an intermediate coupling strength; firing synchronization is minimal simultaneously irrespective of the size of networks. For further increasing the coupling strength, synchronization is enhanced. Since noise is inevitable in real neurons, we also investigate the effects of white noise on firing synchronization for different networks. For the networks of oscillatory neurons, it is shown that firing synchronization decreases when the noise level increases. For the missed networks, firing synchronization is robust under the noise conditions considered in this paper. Results presented in this paper should prove to be valuable for understanding the properties of collective dynamics in real neuronal networks.

  3. Commutative Pattern between Commodity Packaging and Customer Mentality%商品包装与消费者心理的互动关系

    Institute of Scientific and Technical Information of China (English)

    罗秋明; 孙慧; 周跃军

    2012-01-01

    As a bond of communication between commodities and customers, commodity packaging has a commutative relationship with the mentality of customers. On one hand, commodity packaging influences the customers through appearence like color, shape, words, pictures and symbols, which attract their attention, initiate their emotion, inspire their desire, and then, lead to the acquisition. On the other hand, the characteristics and rules of the mentality and behavior of the customers are the gist and precondition of commodity packaging, i.e., commodity packaging shuold conform to the characteristics of individual customer or customers' mental demands as a group.%商品包装作为商品与消费者之间的信息纽带,与消费者心理之间存在着相互影响的互动关系。一方面,商品包装通过色彩、造型、文字、图案、标志等外观形象作用于消费者的感官,促使其产生注意,引发情感,形成动机,导致购买;另一方面,消费者的心理和行为特点及规律又是进行包装设计的依据和前提条件,即商品的包装设计必须符合消费者个体和群体的心理需求特点。

  4. Probing quantum commutators

    CERN Document Server

    Rossi, Matteo A C; Paris, Matteo G A

    2016-01-01

    Quantum gravity theories predict a minimal length at the order of magnitude of the Planck length, under which the concepts of space and time lose every physical meaning. In quantum mechanics, the insurgence of such minimal length can be described by introducing a modified position-momentum commutator, which in turn yields a generalized uncertainty principle, where the uncertainty on the position measurement has a lower bound. The value of the minimal length is not predicted by theories and must be evaluated experimentally. In this paper, we address the quantum bound to estimability of the minimal uncertainty length by performing measurements on a harmonic oscillator, which is analytically solvable in the deformed algebra of the Hilbert subspace.

  5. Combinatorics and commutative algebra

    CERN Document Server

    Stanley, Richard P

    1996-01-01

    Some remarkable connections between commutative algebra and combinatorics have been discovered in recent years. This book provides an overview of two of the main topics in this area. The first concerns the solutions of linear equations in nonnegative integers. Applications are given to the enumeration of integer stochastic matrices (or magic squares), the volume of polytopes, combinatorial reciprocity theorems, and related results. The second topic deals with the face ring of a simplicial complex, and includes a proof of the Upper Bound Conjecture for Spheres. An introductory chapter giving background information in algebra, combinatorics and topology broadens access to this material for non-specialists. New to this edition is a chapter surveying more recent work related to face rings, focusing on applications to f-vectors. Included in this chapter is an outline of the proof of McMullen's g-conjecture for simplicial polytopes based on toric varieties, as well as a discussion of the face rings of such special ...

  6. Commutativity and structure of rings with commuting nilpotents

    Directory of Open Access Journals (Sweden)

    Hazar Abu-Khuzam

    1983-01-01

    Full Text Available Let R be a ring and let N denote the set of nilpotent elements of R. Let Z denote the center of R. Suppose that (i N is commutative, (ii for every x in R there exists x′ϵ such that x−x2x′ϵN, where denotes the subring generated by x, (iii for every x,y in R, there exists an integer n=n(x,y≥1 such that both (xyn−(yxn and (xyn+1−(yxn+1 belong to Z. Then R is commutative and, in fact, R is isomorphic to a subdirect sum of nil commutative rings and local commutative rings. It is further shown that both conditions in hypothesis (iii are essential. The proof uses the structure theory of rings along with some earlier results of the authors.

  7. Commutative and Non-commutative Parallelogram Geometry: an Experimental Approach

    OpenAIRE

    Bertram, Wolfgang

    2013-01-01

    By "parallelogram geometry" we mean the elementary, "commutative", geometry corresponding to vector addition, and by "trapezoid geometry" a certain "non-commutative deformation" of the former. This text presents an elementary approach via exercises using dynamical software (such as geogebra), hopefully accessible to a wide mathematical audience, from undergraduate students and high school teachers to researchers, proceeding in three steps: (1) experimental geometry, (2) algebra (linear algebr...

  8. Mapping the online communication patterns of political conversations

    Science.gov (United States)

    Borondo, J.; Morales, A. J.; Benito, R. M.; Losada, J. C.

    2014-11-01

    The structure of the social networks in which individuals are embedded influences their political choices and therefore their voting behavior. Nowadays, social media represent a new channel for individuals to communicate, what together with the availability of the data, makes it possible to analyze the online social network resulting from political conversations. Here, by taking advantage of the recently developed techniques to analyze complex systems, we map the communication patterns resulting from Spanish political conversations. We identify the different existing communities, building networks of communities, and finding that users cluster themselves in politically homogeneous networks. We found that while most of the collective attention was monopolized by politicians, traditional media accounts were still the preferred sources from which to propagate information. Finally, we propose methods to analyze the use of different languages, finding a clear trend from sympathizers of several political parties to overuse or infra-use each language. We conclude that, on the light of a social media analysis perspective, the political conversation is constrained by both ideology and language.

  9. A class of commutative dynamics of open quantum systems

    CERN Document Server

    Chruscinski, D; Aniello, P; Marmo, G; Ventriglia, F

    2010-01-01

    We analyze a class of dynamics of open quantum systems which is governed by the dynamical map mutually commuting at different times. Such evolution may be effectively described via spectral analysis of the corresponding time dependent generators. We consider both Markovian and non-Markovian cases.

  10. Active commuting of the inhabitants of Liberec city in low and high walkability areas

    Directory of Open Access Journals (Sweden)

    Lukáš Rubín

    2015-12-01

    Full Text Available Background: Active commuting in terms of everyday transport to school or work can have a significant effect on physical activity. Active commuting can be influenced by the environment, and examples from abroad show that current environmental changes tend mostly to promote passive forms of commuting. A similar situation of decreasing active commuting might be expected in the Czech Republic. However, little information has been published to date about the issue of active commuting among the inhabitants of our country. Objective: The main objective of the present study is to describe the active commuting patterns of the inhabitants of Liberec city in low and high walkability areas. Methods: A total of 23,621 economically active inhabitants or students of Liberec city aged 6-87 years (34.77 ± 14.39 participated in the study. The data about commuting were retrieved from the national Population and Housing Census of 2011. Geographic information systems were used to objectively analyze the built environment and to calculate the walkability index. Results: Active commuting to/from school or work is used by 17.41% of inhabitants. Active commuting is dominated by walking (16.60% as opposed to cycling (0.81%. Inhabitants who lived in high walkability areas were more likely to actively commute than those living in low walkability areas (OR = 1.54; 95% CI [1.41, 1.68]. Conclusions: This study confirmed the findings of international studies about the effect of the built environment on active commuting among Liberec inhabitants. Active commuters are often those living near or in the city center, which is characterized by high walkability. In Liberec city, walking as a means of active commuting significantly prevails over cycling. One of the reasons might be the diverse topography of the city and the insufficiently developed cycling network.

  11. Commuting Π-regular rings

    Directory of Open Access Journals (Sweden)

    Shervin Sahebi

    2014-05-01

    Full Text Available ‎$R$ is called commuting regular ring (resp‎. ‎semigroupif‎ for each $x,y\\in R$ there exists $a\\in R$‎ such that$xy=yxayx$‎. ‎In this paper‎, ‎we introduce the concept of‎‎commuting $\\pi$-regular rings (resp‎. ‎semigroups and‎‎study various properties of them.

  12. Commuting projections on graphs

    Energy Technology Data Exchange (ETDEWEB)

    Vassilevski, Panayot S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Center for Applied Scientific Computing; Zikatanov, Ludmil T. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mathematics

    2013-02-19

    For a given (connected) graph, we consider vector spaces of (discrete) functions defined on its vertices and its edges. These two spaces are related by a discrete gradient operator, Grad and its adjoint, ₋Div, referred to as (negative) discrete divergence. We also consider a coarse graph obtained by aggregation of vertices of the original one. Then a coarse vertex space is identified with the subspace of piecewise constant functions over the aggregates. We consider the ℓ2-projection QH onto the space of these piecewise constants. In the present paper, our main result is the construction of a projection π H from the original edge-space onto a properly constructed coarse edge-space associated with the edges of the coarse graph. The projections π H and QH commute with the discrete divergence operator, i.e., we have div π H = QH div. The respective pair of coarse edge-space and coarse vertexspace offer the potential to construct two-level, and by recursion, multilevel methods for the mixed formulation of the graph Laplacian which utilizes the discrete divergence operator. The performance of one two-level method with overlapping Schwarz smoothing and correction based on the constructed coarse spaces for solving such mixed graph Laplacian systems is illustrated on a number of graph examples.

  13. Some operator ideals in non-commutative functional analysis

    CERN Document Server

    Fidaleo, F

    1997-01-01

    We characterize classes of linear maps between operator spaces $E$, $F$ which factorize through maps arising in a natural manner via the Pisier vector-valued non-commutative $L^p$ spaces $S_p[E^*]$ based on the Schatten classes on the separable Hilbert space $l^2$. These classes of maps can be viewed as quasi-normed operator ideals in the category of operator spaces, that is in non-commutative (quantized) functional analysis. The case $p=2$ provides a Banach operator ideal and allows us to characterize the split property for inclusions of $W^*$-algebras by the 2-factorable maps. The various characterizations of the split property have interesting applications in Quantum Field Theory.

  14. Bilangan Kromatik Grap Commuting dan Non Commuting Grup Dihedral

    Directory of Open Access Journals (Sweden)

    Handrini Rahayuningtyas

    2015-11-01

    Full Text Available Commuting graph is a graph that has a set of points X and two different vertices to be connected directly if each commutative in G. Let G non abelian group and Z(G is a center of G. Noncommuting graph is a graph which the the vertex is a set of G\\Z(G and two vertices x and y are adjacent if and only if xy≠yx. The vertex colouring of G is giving k colour at the vertex, two vertices that are adjacent not given the same colour. Edge colouring of G is two edges that have common vertex are coloured with different colour. The smallest number k so that a graph can be coloured by assigning k colours to the vertex and edge called chromatic number. In this article, it is available the general formula of chromatic number of commuting and noncommuting graph of dihedral group

  15. Trade-offs between commuting time and health-related activities.

    Science.gov (United States)

    Christian, Thomas J

    2012-10-01

    To further understand documented associations between obesity and urban sprawl, this research describes individuals' trade-offs between health-related activities and commuting time. A cross-section of 24,861 working-age individuals employed full-time and residing in urban counties is constructed from the American Time Use Survey (2003-2010). Data are analyzed using seemingly unrelated regressions to quantify health-related activity decreases in response to additional time spent commuting. Outcomes are total daily minutes spent in physical activity at a moderate or greater intensity, preparing food, eating meals with family, and sleeping. Commuting time is measured as all travel time between home and work and vice versa. The mean commuting time is 62 min daily, the median is 55 min, and 10.1% of workers commute 120 min or more. Spending an additional 60 min daily commuting above average is associated with a 6% decrease in aggregate health-related activities and spending an additional 120 min is associated with a 12% decrease. The greatest percentage of commuting time comes from sleeping time reductions (28-35%). Additionally, larger proportions of commuting time are taken from physical activity and food preparation relative to the mean commuting length: of 60 min spent commuting, 16.1% is taken from physical activity and 4.1% is taken from food preparation; of 120 min commuting, 20.3% is taken from physical activity and 5.6% is taken from food preparation. The results indicate that longer commutes are associated with behavioral patterns which over time may contribute to obesity and other poor health outcomes. These findings will assist both urban planners and researchers wishing to understand time constraints' impacts on health.

  16. Recombination patterns reveal information about centromere location on linkage maps

    DEFF Research Database (Denmark)

    Limborg, Morten T.; McKinney, Garrett J.; Seeb, Lisa W.

    2016-01-01

    , approximate centromere placement is possible by phasing the same data used to generate linkage maps. Assuming one obligate crossover per chromosome arm, information about centromere location can be revealed by tracking the accumulated recombination frequency along linkage groups, similar to half....... mykiss) characterized by low and unevenly distributed recombination – a general feature of male meiosis in many species. Further, a high frequency of double crossovers along chromosome arms in barley reduced resolution for locating centromeric regions on most linkage groups. Despite these limitations......, our method should work well for high‐density maps in species with strong recombination interference and will enrich many existing and future mapping resources....

  17. Trip chain pattern choice behavior of commuters based on traffic information%基于交通信息的通勤出行链模式选择行为

    Institute of Scientific and Technical Information of China (English)

    张华歆; 张丽杰

    2015-01-01

    为探索通过智能手机等通信工具随时随地获得的交通信息对居民通勤出行链模式选择行为的影响,采用RP(Revealed Preference)调查获取出行者的社会经济属性、交通信息使用属性以及通勤出行链模式选择行为数据,用信息查询频率度量出行者的交通信息使用属性,建立估计通勤出行链模式的二项Logit模型。研究发现:(1)交通信息在促进复杂链的生成上发挥着较大的作用;(2)在交通信息的作用下,停车换乘(Park and Ride,P&R)方式比公共交通和小汽车都更能促进复杂链的生成;(3)出行者的性别、婚姻状态、家中是否有12周岁以下儿童等对出行链模式选择不会有显著影响。%To discuss the impact of traffic information that can be obtained anywhere at any time through smart phones on commuters’trip chain pattern choice behavior,RP (Revealed Preference)survey is a-dopted to collect the commuters ’ socio-demographic attributes,traffic information attributes and trip chain pattern choice data. The traffic information attributes are measured by the information query fre-quency. A binary Logit model is built to quantify the commuters’trip chain pattern choice. It shows that:(1 )the traffic information plays a great role in promoting the generation of complex chain;(2 )the travel mode of Park & Ride(P&R)is more likely to promote the generation of complex chain under the traffic information than the public and private transport modes;(3)the commuters’gender,marital sta-tus and whether there are children under the age of 12 in their family don’t have a significant impact on their trip chain pattern choice.

  18. Electromagnetic Gun With Commutated Coils

    Science.gov (United States)

    Elliott, David G.

    1991-01-01

    Proposed electromagnetic gun includes electromagnet coil, turns of which commutated in sequence along barrel. Electrical current fed to two armatures by brushes sliding on bus bars in barrel. Interaction between armature currents and magnetic field from coil produces force accelerating armature, which in turn, pushes on projectile. Commutation scheme chosen so magnetic field approximately coincides and moves with cylindrical region defined by armatures. Scheme has disadvantage of complexity, but in return, enables designer to increase driving magnetic field without increasing armature current. Attainable muzzle velocity increased substantially.

  19. Positive multiplication preserves dissipativity in commutative -algebras

    Directory of Open Access Journals (Sweden)

    Sommariva Alvise

    2001-01-01

    Full Text Available We prove that multiplication by a positive element preserves dissipativity (accretivity in the framework of commutative -algebras. A simple counterexample shows that the result is not valid, in general, in commutative involutory Banach algebras.

  20. Bilinear decompositions and commutators of singular integral operators

    CERN Document Server

    Ky, Luong Dang

    2011-01-01

    Let $b$ be a $BMO$-function. It is well-known that the linear commutator $[b, T]$ of a Calder\\'on-Zygmund operator $T$ does not, in general, map continuously $H^1(\\mathbb R^n)$ into $L^1(\\mathbb R^n)$. However, P\\'erez \\cite{Pe} showed that if $H^1(\\mathbb R^n)$ is replaced by a suitable atomic subspace $\\mathcal H^1_b(\\mathbb R^n)$ then the commutator is continuous from $\\mathcal H^1_b(\\mathbb R^n)$ into $L^1(\\mathbb R^n)$. In this paper, we find the largest subspace $H^1_b(\\mathbb R^n)$ such that all commutators of Calder\\'on-Zygmund operators are continuous from $H^1_b(\\mathbb R^n)$ into $L^1(\\mathbb R^n)$. We also study the commutators $[b,T]$ for $T$ in a class $\\mathcal K$ of sublinear operators containing almost all important operators in Harmonic analysis. When $T$ is linear, we prove that there exists a bilinear operators $\\mathfrak R$ map continuously $H^1(\\mathbb R^n)\\times BMO(\\mathbb R^n)$ into $L^1(\\mathbb R^n)$ such that for all $(f,b)\\in H^1(\\mathbb R^n)\\times BMO(\\mathbb R^n)$, we have\\label{...

  1. Non-commutative and commutative vacua effects in a scalar torsion scenario

    Energy Technology Data Exchange (ETDEWEB)

    Sheikhahmadi, Haidar, E-mail: h.sh.ahmadi@gmail.com [Department of Physics, Faculty of Science, University of Kurdistan, Sanandaj (Iran, Islamic Republic of); Aghamohammadi, Ali, E-mail: a.aghamohamadi@iausdj.ac.ir [Sanandaj Branch, Islamic Azad University, Sanandaj (Iran, Islamic Republic of); Saaidi, Khaled, E-mail: ksaaidi@uok.ac.ir [Department of Physics, Faculty of Science, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

    2015-10-07

    In this work, the effects of non-commutative and commutative vacua on the phase space generated by a scalar field in a scalar torsion scenario are investigated. For both classical and quantum regimes, the commutative and non-commutative cases are compared. To take account the effects of non-commutativity, two well known non-commutative parameters, θ and β, are introduced. It should be emphasized, the effects of β which is related to momentum sector has more key role in comparison to θ which is related to space sector. Also the different boundary conditions and mathematical interpretations of non-commutativity are explored.

  2. Non-commutative and commutative vacua effects in a scalar torsion scenario

    Directory of Open Access Journals (Sweden)

    Haidar Sheikhahmadi

    2015-10-01

    Full Text Available In this work, the effects of non-commutative and commutative vacua on the phase space generated by a scalar field in a scalar torsion scenario are investigated. For both classical and quantum regimes, the commutative and non-commutative cases are compared. To take account the effects of non-commutativity, two well known non-commutative parameters, θ and β, are introduced. It should be emphasized, the effects of β which is related to momentum sector has more key role in comparison to θ which is related to space sector. Also the different boundary conditions and mathematical interpretations of non-commutativity are explored.

  3. A study of commuter airline economics

    Science.gov (United States)

    Summerfield, J. R.

    1976-01-01

    Variables are defined and cost relationships developed that describe the direct and indirect operating costs of commuter airlines. The study focused on costs for new aircraft and new aircraft technology when applied to the commuter airline industry. With proper judgement and selection of input variables, the operating costs model was shown to be capable of providing economic insight into other commuter airline system evaluations.

  4. 8 CFR 211.5 - Alien commuters.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Alien commuters. 211.5 Section 211.5 Aliens...: IMMIGRANTS; WAIVERS § 211.5 Alien commuters. (a) General. An alien lawfully admitted for permanent residence.... An alien commuter engaged in seasonal work will be presumed to have taken up residence in the...

  5. On the Fractional Extensions in Commutative Ordered Semigroups%可换序半群的分式扩张

    Institute of Scientific and Technical Information of China (English)

    罗从文

    2008-01-01

    In this paper we extend the construction of the field of rational numbers from the ring of integers to an arbitrary commutative ordered semigroup.We first construct a fractional ordered semigroup and a homomorphism ψs:R→S-1R.Secondly,we characterize the commutative ordered semigroup so constructed by a universal mapping property.

  6. Mapping of hydropedologic spatial patterns in a steep headwater catchment

    Science.gov (United States)

    Cody P. Gillin; Scott W. Bailey; Kevin J. McGuire; John P. Gannon

    2015-01-01

    A hydropedologic approach can be used to describe soil units affected by distinct hydrologic regimes. We used field observations of soil morphology and geospatial information technology to map the distribution of five hydropedologic soil units across a 42-ha forested headwater catchment. Soils were described and characterized at 172 locations within Watershed 3, the...

  7. Workers' marginal costs of commuting

    DEFF Research Database (Denmark)

    van Ommeren, Jos; Fosgerau, Mogens

    2009-01-01

    This paper applies a dynamic search model to estimate workers' marginal costs of commuting, including monetary and time costs. Using data on workers' job search activity as well as moving behaviour, for the Netherlands, we provide evidence that, on average, workers' marginal costs of one hour...

  8. On the commutator of unit quaternions

    CERN Document Server

    Puettmann, Thomas

    2011-01-01

    The quaternions are non-commutative. The deviation from commutativity is encapsulated in the commutator of unit quaternions. It is known that the k-th power of the commutator is null-homotopic if and only if k is divisible by 12. The main purpose of this paper is to construct a concrete null-homotopy of the 12-th power of the commutator. Subsequently, we construct free S^3-actions on S^7 x S^3 whose quotients are exotic 7-spheres.

  9. Reducing employee travelling time through smart commuting

    Science.gov (United States)

    Rahman, A. N. N. A.; Yusoff, Z. M.; Aziz, I. S.; Omar, D.

    2014-02-01

    Extremely congested roads will definitely delay the arrival time of each trip.This certainly impacted the journey of employees. Tardiness at the workplace has become a perturbing issue for companies where traffic jams are the most common worker excuses. A depressing consequence on daily life and productivity of the employee occurs. The issues of commuting distance between workplace and resident area become the core point of this research. This research will emphasize the use of Geographical Information System (GIS) technique to explore the distance parameter to the employment area and will focus on the accessibility pattern of low-cost housing. The research methodology consists of interview sessions and a questionnaire to residents of low-cost housing areas in Melaka Tengah District in Malaysia. The combination of these processes will show the criteria from the selected parameter for each respondent from their resident area to the employment area. This will further help in the recommendation of several options for a better commute or improvement to the existing routes and public transportations system. Thus enhancing quality of life for employees and helping to reduce stress, decrease lateness, absenteeism and improving productivity in workplace.

  10. Non-commutativity in polar coordinates

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, James P. [Universidad Michoacana de San Nicolas de Hidalgo, Ciudad Universitaria, Instituto de Fisica y Matematicas, Morelia, Michoacan (Mexico)

    2017-05-15

    We reconsider the fundamental commutation relations for non-commutative R{sup 2} described in polar coordinates with non-commutativity parameter θ. Previous analysis found that the natural transition from Cartesian coordinates to the traditional polar system led to a representation of [r, φ] as an everywhere diverging series. In this article we compute the Borel resummation of this series, showing that it can subsequently be extended throughout parameter space and hence provide an interpretation of this commutator. Our analysis provides a complete solution for arbitrary r and θ that reproduces the earlier calculations at lowest order and benefits from being generally applicable to problems in a two-dimensional non-commutative space. We compare our results to previous literature in the (pseudo-)commuting limit, finding a surprising spatial dependence for the coordinate commutator when θ >> r{sup 2}. Finally, we raise some questions for future study in light of this progress. (orig.)

  11. Mapping patterns and characteristics of fatal road accidents in Israel

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Gitelman, Victoria; Bekhor, Shlomo

    2010-01-01

    This paper intends to provide a broad picture of traffic accidents in Israel by uncovering their patterns and determinants in order to answer an increasing need of designing preventive measures, addressing particular situations and targeting specific social groups with the ultimate objective...

  12. Spatial sensitivity mapping of Hall crosses using patterned magnetic nanostructures

    NARCIS (Netherlands)

    Alexandrou, M.; Nutter, P.W.; Delalande, M.Y.; Vries, de J.; Hill, E.W.; Schedin, F.; Abelmann, L.; Thomson, T.

    2010-01-01

    Obtaining an accurate profile of the spatial sensitivity of Hall cross structures is crucial if such devices are to be used to analyze the switching behavior of magnetic nanostructures and determine the switching field distribution of bit patterned media. Here, we have used the anomalous Hall effect

  13. Standardized mapping of nodulation patterns in legume roots.

    Science.gov (United States)

    Remmler, Lauren; Clairmont, Lindsey; Rolland-Lagan, Anne-Gaëlle; Guinel, Frédérique Catherine

    2014-05-01

    Optimizing nodulation in legumes is a target for crop improvement, and the spatial control of nodulation is just beginning to be unravelled. However, there is currently no method for standard phenotyping of nodulation patterns. Here we present a method and software for the quantitative analysis of nodulation phenotypes. Roots of nodulated peas (Pisum sativum), wild-type and two mutants, were photographed. Data from the photographs were extracted using custom image and data analysis software. The software makes it possible to extract each nodule's position along primary and lateral roots, and to represent the nodulated root system in a standardized way independent of the way roots are arranged in the soil. A wide variety of nodulation and root variables are calculated, and average spatial nodulation patterns can be computed from multiple samples. Standardized spatial analysis of nodulation patterns opens the way for comparative analyses among genotypes of a single legume species, as here in pea. This approach could also be used to compare nodulation patterns among crops, among plants grown under different environmental conditions, or among plants exposed to different pharmacological treatments. The proposed method should therefore prove useful for studies on nodule organogenesis and nodule physiology and for optimizing nodulation in crops. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  14. Instant MapReduce patterns Hadoop essentials how-to

    CERN Document Server

    Perera, Srinath

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. This is a Packt Instant How-to guide, which provides concise and clear recipes for getting started with Hadoop.This book is for big data enthusiasts and would-be Hadoop programmers. It is also meant for Java programmers who either have not worked with Hadoop at all, or who know Hadoop and MapReduce but are not sure how to deepen their understanding.

  15. Recognizing lexical and semantic change patterns in evolving life science ontologies to inform mapping adaptation.

    Science.gov (United States)

    Dos Reis, Julio Cesar; Dinh, Duy; Da Silveira, Marcos; Pruski, Cédric; Reynaud-Delaître, Chantal

    2015-03-01

    Mappings established between life science ontologies require significant efforts to maintain them up to date due to the size and frequent evolution of these ontologies. In consequence, automatic methods for applying modifications on mappings are highly demanded. The accuracy of such methods relies on the available description about the evolution of ontologies, especially regarding concepts involved in mappings. However, from one ontology version to another, a further understanding of ontology changes relevant for supporting mapping adaptation is typically lacking. This research work defines a set of change patterns at the level of concept attributes, and proposes original methods to automatically recognize instances of these patterns based on the similarity between attributes denoting the evolving concepts. This investigation evaluates the benefits of the proposed methods and the influence of the recognized change patterns to select the strategies for mapping adaptation. The summary of the findings is as follows: (1) the Precision (>60%) and Recall (>35%) achieved by comparing manually identified change patterns with the automatic ones; (2) a set of potential impact of recognized change patterns on the way mappings is adapted. We found that the detected correlations cover ∼66% of the mapping adaptation actions with a positive impact; and (3) the influence of the similarity coefficient calculated between concept attributes on the performance of the recognition algorithms. The experimental evaluations conducted with real life science ontologies showed the effectiveness of our approach to accurately characterize ontology evolution at the level of concept attributes. This investigation confirmed the relevance of the proposed change patterns to support decisions on mapping adaptation. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Universal commutative operator algebras and transfer function realizations of polynomials

    CERN Document Server

    Jury, Michael T

    2010-01-01

    To each finite-dimensional operator space $E$ is associated a commutative operator algebra $UC(E)$, so that $E$ embeds completely isometrically in $UC(E)$ and any completely contractive map from $E$ to bounded operators on Hilbert space extends uniquely to a completely contractive homomorphism out of $UC(E)$. The unit ball of $UC(E)$ is characterized by a Nevanlinna factorization and transfer function realization. Examples related to multivariable von Neumann inequalities are discussed.

  17. Mapping Reactive Flow Patterns in Monolithic Nanoporous Catalysts

    CERN Document Server

    Falcucci, Giacomo; Montessori, Andrea; Melchionna, Simone; Prestininzi, Pietro; Barroo, Cedric; Bell, David C; Biener, Monika M; Biener, Juergen; Zugic, Branko; Kaxiras, Efthimios

    2016-01-01

    The development of high-efficiency porous catalyst membranes critically depends on our understanding of where the majority of the chemical conversions occur within the porous structure. This requires mapping of chemical reactions and mass transport inside the complex nano-scale architecture of porous catalyst membranes which is a multiscale problem in both the temporal and spatial domain. To address this problem, we developed a multi-scale mass transport computational framework based on the Lattice Boltzmann Method (LBM) that allows us to account for catalytic reactions at the gas-solid interface by introducing a new boundary condition. In good agreement with experiments, the simulations reveal that most catalytic reactions occur near the gas-flow facing side of the catalyst membrane if chemical reactions are fast compared to mass transport within the porous catalyst membrane.

  18. Spatial patterns of landslide dimension: A tool for magnitude mapping

    Science.gov (United States)

    Catani, Filippo; Tofani, Veronica; Lagomarsino, Daniela

    2016-11-01

    The magnitude of mass movements, which may be expressed by their dimension in terms of area or volume, is an important component of intensity together with velocity. In the case of slow-moving deep-seated landslides, the expected magnitude is the prevalent parameter for defining intensity when assessed as a spatially distributed variable in a given area. In particular, the frequency-volume statistics of past landslides may be used to understand and predict the magnitude of new landslides and reactivations. In this paper we study the spatial properties of volume frequency distributions in the Arno river basin (Central Italy, about 9100 km2). The overall landslide inventory taken into account (around 27,500 events) shows a power-law scaling of volumes for values greater than a cutoff value of about 2 × 104 m3. We explore the variability of the power-law exponent in the geographic space by setting up local subsets of the inventory based on neighbourhoods with radii between 5 and 50 km. We found that the power-law exponent α varies according to geographic position and that the exponent itself can be treated as a random space variable with autocorrelation properties both at local and regional scale. We use this finding to devise a simple method to map the magnitude frequency distribution in space and to create maps of exceeding probability of landslide volume for risk analysis. We also study the causes of spatial variation of α by analysing the dependence of power-law properties on geological and geomorphological factors, and we find that structural settings and valley density exert a strong influence on mass movement dimensions.

  19. Non-commutative Nash inequalities

    Energy Technology Data Exchange (ETDEWEB)

    Kastoryano, Michael [NBIA, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen (Denmark); Temme, Kristan [Institute for Quantum Information and Matter, California Institute of Technology, Pasadena California 91125 (United States)

    2016-01-15

    A set of functional inequalities—called Nash inequalities—are introduced and analyzed in the context of quantum Markov process mixing. The basic theory of Nash inequalities is extended to the setting of non-commutative L{sub p} spaces, where their relationship to Poincaré and log-Sobolev inequalities is fleshed out. We prove Nash inequalities for a number of unital reversible semigroups.

  20. Combining point correlation maps with self-organising maps to compare observed and simulated atmospheric teleconnection patterns

    Directory of Open Access Journals (Sweden)

    Freja K. Hunt

    2013-07-01

    Full Text Available We use a new method based on point correlation maps and self-organising maps (SOMs to identify teleconnection patterns in 60 yr of National Centres for Environmental Prediction/National Centre for Atmospheric Research (NCEP/NCAR sea level pressure (SLP re-analysis data. The most prevalent patterns are the El Nino Southern Oscillation (ENSO, the North Atlantic Oscillation (NAO and the Southern Annular Mode (SAM. Asymmetries are found between base points in opposite centres of action of the NAO and the Pacific North America pattern (PNA. The SOM-based method is a powerful tool that allows us to efficiently assess how realistically teleconnections are reproduced in any climate model. The degree of agreement between modelled and re-analysis-based teleconnections (or between different models can be summarised in a single plot. Here, we illustrate this by assessing the skill of the medium complexity climate model FORTE (Fast Ocean Rapid Troposphere Experiment. FORTE reproduces some realistic teleconnections, such as the Arctic Oscillation (AO, the NAO, the PNA, the SAM, the African Monsoon and ENSO, along with several other teleconnections, which resemble to varying degrees the corresponding NCEP patterns. However, FORTE tends to underestimate the strength of the correlation patterns and the patterns tend to be slightly too zonal. The accuracy of frequency of occurrence is variable between patterns. The Indian Ocean is a region where FORTE performs poorly, as it does not reproduce the teleconnection patterns linked to the Indian Monsoon. In contrast, the North and equatorial Pacific and North Atlantic are reasonably well reproduced.

  1. Mapping patterns of pedestrian fatal accidents in Israel

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Gitelman, Victoria; Bekhor, Shlomo

    2010-01-01

    -year period between 2003 and 2006. Results show the existence of five pedestrian accident patterns: (i) elderly pedestrians crossing on crosswalks far from intersection in metropolitan areas; (ii) pedestrians crossing suddenly or from hidden places and colliding with two-wheel vehicles on urban road sections......; (iii) male pedestrians crossing at night and being hit by four-wheel vehicles on rural road sections; (iv) young male pedestrians crossing at night wide road sections in both urban and rural areas; (v) children and teenagers crossing road sections in small rural communities. From the policy perspective......, results suggest the necessity of designing education campaigns for parents, promoting information campaigns for road users and allocating resources for infrastructural interventions and law enforcement in order to address the identified major problems....

  2. Local current mapping and patterning of reduced graphene oxide.

    Science.gov (United States)

    Mativetsky, Jeffrey M; Treossi, Emanuele; Orgiu, Emanuele; Melucci, Manuela; Veronese, Giulio Paolo; Samorì, Paolo; Palermo, Vincenzo

    2010-10-13

    Conductive atomic force microscopy (C-AFM) has been used to correlate the detailed structural and electrical characteristics of graphene derived from graphene oxide. Uniform large currents were measured over areas exceeding tens of micrometers in few-layer films, supporting the use of graphene as a transparent electrode material. Moreover, defects such as electrical discontinuities were easily detected. Multilayer films were found to have a higher conductivity per layer than single layers. It is also shown that a local AFM-tip-induced electrochemical reduction process can be used to pattern conductive pathways on otherwise-insulating graphene oxide. Transistors with micrometer-scale tip-reduced graphene channels that featured ambipolar transport and an 8 order of magnitude increase in current density upon reduction were successfully fabricated.

  3. Happiness and Satisfaction with Work Commute.

    Science.gov (United States)

    Olsson, Lars E; Gärling, Tommy; Ettema, Dick; Friman, Margareta; Fujii, Satoshi

    2013-03-01

    Research suggests that for many people happiness is being able to make the routines of everyday life work, such that positive feelings dominate over negative feelings resulting from daily hassles. In line with this, a survey of work commuters in the three largest urban areas of Sweden show that satisfaction with the work commute contributes to overall happiness. It is also found that feelings during the commutes are predominantly positive or neutral. Possible explanatory factors include desirable physical exercise from walking and biking, as well as that short commutes provide a buffer between the work and private spheres. For longer work commutes, social and entertainment activities either increase positive affects or counteract stress and boredom. Satisfaction with being employed in a recession may also spill over to positive experiences of work commutes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11205-012-0003-2) contains supplementary material, which is available to authorized users.

  4. Non-commutativity in polar coordinates

    CERN Document Server

    Edwards, James P

    2016-01-01

    We reconsider the fundamental commutation relations for non-commutative $\\mathbb{R}^{2}$ described in polar coordinates with non-commutativity parameter $\\theta$. Previous analysis found that the natural transition from Cartesian coordinates to polars led to a representation of $\\left[\\hat{r}, \\hat{\\varphi}\\right]$ as an everywhere diverging series. We compute the Borel resummation of this series, showing that it can subsequently be extended throughout parameter space and hence provide an interpretation of this commutator. Our analysis provides a complete solution for arbitrary $r$ and $\\theta$ that reproduces the earlier calculations at lowest order. We compare our results to previous literature in the (pseudo-)commuting limit, finding a surprising spatial dependence for the coordinate commutator when $\\theta \\gg r^{2}$. We raise some questions for future study in light of this progress.

  5. Mapping mobility patterns to public spaces in a medium-sized city using geolocated tweets

    CERN Document Server

    Salas-Olmedo, María Henar

    2016-01-01

    This research evidences the usefulness of open big data to map mobility patterns in a medium-sized city. Motivated by the novel analysis that big data allow worldwide and in large metropolitan areas, we developed a methodology aiming to complement origin-destination surveys with \\`a la carte spatial boundaries and updated data at a minimum cost. This paper validates the use of Twitter data to map the impact of public spaces on the different parts of the metropolitan area of Concepci\\'on, Chile. Results have been validated by local experts and evidence the main mobility patterns towards spaces of social interaction like malls, leisure areas, parks and so on. The map represents the mobility patterns from census districts to different categories of public spaces with schematic lines at the metropolitan scale and it is centred in the city of Concepci\\'on (Chile) and its surroundings (~10 kilometres).

  6. Pattern identification or 3D visualization? How best to learn topographic map comprehension

    Science.gov (United States)

    Atit, Kinnari

    Science, Technology, Engineering, and Mathematics (STEM) experts employ many representations that novices find hard to use because they require a critical STEM skill, interpreting two-dimensional (2D) diagrams that represent three-dimensional (3D) information. The current research focuses on learning to interpret topographic maps. Understanding topographic maps requires knowledge of how to interpret the conventions of contour lines, and skill in visualizing that information in 3D (e.g. shape of the terrain). Novices find both tasks difficult. The present study compared two interventions designed to facilitate understanding for topographic maps to minimal text-only instruction. The 3D Visualization group received instruction using 3D gestures and models to help visualize three topographic forms. The Pattern Identification group received instruction using pointing and tracing gestures to help identify the contour patterns associated with the three topographic forms. The Text-based Instruction group received only written instruction explaining topographic maps. All participants then completed a measure of topographic map use. The Pattern Identification group performed better on the map use measure than participants in the Text-based Instruction group, but no significant difference was found between the 3D Visualization group and the other two groups. These results suggest that learning to identify meaningful contour patterns is an effective strategy for learning how to comprehend topographic maps. Future research should address if learning strategies for how to interpret the information represented on a diagram (e.g. identify patterns in the contour lines), before trying to visualize the information in 3D (e.g. visualize the 3D structure of the terrain), also facilitates students' comprehension of other similar types of diagrams.

  7. Product and Commutativity of Slant Toeplitz Operators

    Institute of Scientific and Technical Information of China (English)

    Chaomei LIU; Yufeng LU

    2013-01-01

    In this paper,the product and commutativity of slant Toeplitz operators are discussed.We show that the product of kth1-order slant Toeplitz operators and kth2-order slant Toeplitz operators must be a (k1k2)th-order slant Toeplitz operator except for zero operators,and the commutativity and essential commutativity of two slant Toeplitz operators with different orders are the same.

  8. Environmental health citation patterns: mapping the literature 2008–2010

    Science.gov (United States)

    Rethlefsen, Melissa L

    2013-01-01

    Objective: This research seeks to understand the publication types and ages cited most often in environmental health literature and the most commonly cited journal titles. Methods: From the 43,896 items cited in Environmental Health Perspectives and the Journal of Environmental Health during 2008–2010, 2 random samples were drawn: First, 1,042 items representing all citations were analyzed with respect to publication type, age, and Internet link. Second, the cited journal name and citation age were recorded for 1,038 items culled from only citations to journal articles. All journal titles were classified into Bradford zones and assigned subject disciplines. Results: Journal articles (n = 891, 85.5%) were the most heavily cited publication type. Cited items' publication years ranged from 1951 to 2010. Close to half (49.1%) of all cited items were published 5 or fewer years previous. Sixteen journal titles (3.9%) accounted for 32.5% of all cited journal articles. The 3 most common subject disciplines—“Public, Environmental & Occupational Health,” “Environmental Sciences,” and “Toxicology”—accounted for 21.6% of all unique journal titles and 45.3% of all citations. Conclusions: Environmental health citation patterns differ from other public health disciplines in terms of cited publication types, cited journals, and age of citations. PMID:23405046

  9. Environmental health citation patterns: mapping the literature 2008-2010.

    Science.gov (United States)

    Rethlefsen, Melissa L; Aldrich, Alison M

    2013-01-01

    This research seeks to understand the publication types and ages cited most often in environmental health literature and the most commonly cited journal titles. From the 43,896 items cited in Environmental Health Perspectives and the Journal of Environmental Health during 2008-2010, 2 random samples were drawn: First, 1,042 items representing all citations were analyzed with respect to publication type, age, and Internet link. Second, the cited journal name and citation age were recorded for 1,038 items culled from only citations to journal articles. All journal titles were classified into Bradford zones and assigned subject disciplines. Journal articles (n = 891, 85.5%) were the most heavily cited publication type. Cited items' publication years ranged from 1951 to 2010. Close to half (49.1%) of all cited items were published 5 or fewer years previous. Sixteen journal titles (3.9%) accounted for 32.5% of all cited journal articles. The 3 most common subject disciplines-"Public, Environmental & Occupational Health," "Environmental Sciences," and "Toxicology"-accounted for 21.6% of all unique journal titles and 45.3% of all citations. Environmental health citation patterns differ from other public health disciplines in terms of cited publication types, cited journals, and age of citations.

  10. Commutation circuit for an HVDC circuit breaker

    Science.gov (United States)

    Premerlani, William J.

    1981-01-01

    A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components.

  11. An alternative way to explain how non-commutativity arises in the bosonic string theory

    CERN Document Server

    De Andrade, M A

    2015-01-01

    In this work we will investigate how the non-commutativity arises into the string theory, \\textit{i.e.}, how the bosonic string theory attaches to a D3-brane in the presence of magnetic fields. In order to accomplish the proposal, we departure from the commutative two-dimensional harmonic oscillator, which after the application of the general Bopp's shifts Matrix Method, the non-commutative version of the two-dimensional harmonic oscillator is obtained. After that, this non-commutative harmonic oscillator will be mapped into the bosonic string theory in the light cone frame, which it now appears as a bosonic string theory attached to a D3-brane.

  12. Challenges for mapping cyanotoxin patterns from remote sensing of cyanobacteria.

    Science.gov (United States)

    Stumpf, Richard P; Davis, Timothy W; Wynne, Timothy T; Graham, Jennifer L; Loftin, Keith A; Johengen, Thomas H; Gossiaux, Duane; Palladino, Danna; Burtner, Ashley

    2016-04-01

    Using satellite imagery to quantify the spatial patterns of cyanobacterial toxins has several challenges. These challenges include the need for surrogate pigments - since cyanotoxins cannot be directly detected by remote sensing, the variability in the relationship between the pigments and cyanotoxins - especially microcystins (MC), and the lack of standardization of the various measurement methods. A dual-model strategy can provide an approach to address these challenges. One model uses either chlorophyll-a (Chl-a) or phycocyanin (PC) collected in situ as a surrogate to estimate the MC concentration. The other uses a remote sensing algorithm to estimate the concentration of the surrogate pigment. Where blooms are mixtures of cyanobacteria and eukaryotic algae, PC should be the preferred surrogate to Chl-a. Where cyanobacteria dominate, Chl-a is a better surrogate than PC for remote sensing. Phycocyanin is less sensitive to detection by optical remote sensing, it is less frequently measured, PC laboratory methods are still not standardized, and PC has greater intracellular variability. Either pigment should not be presumed to have a fixed relationship with MC for any water body. The MC-pigment relationship can be valid over weeks, but have considerable intra- and inter-annual variability due to changes in the amount of MC produced relative to cyanobacterial biomass. To detect pigments by satellite, three classes of algorithms (analytic, semi-analytic, and derivative) have been used. Analytical and semi-analytical algorithms are more sensitive but less robust than derivatives because they depend on accurate atmospheric correction; as a result derivatives are more commonly used. Derivatives can estimate Chl-a concentration, and research suggests they can detect and possibly quantify PC. Derivative algorithms, however, need to be standardized in order to evaluate the reproducibility of parameterizations between lakes. A strategy for producing useful estimates of

  13. Challenges for mapping cyanotoxin patterns from remote sensing of cyanobacteria

    Science.gov (United States)

    Stumpf, Rick P; Davis, Timothy W.; Wynne, Timothy T.; Graham, Jennifer; Loftin, Keith A.; Johengen, T.H.; Gossiaux, D.; Palladino, D.; Burtner, A.

    2016-01-01

    Using satellite imagery to quantify the spatial patterns of cyanobacterial toxins has several challenges. These challenges include the need for surrogate pigments – since cyanotoxins cannot be directly detected by remote sensing, the variability in the relationship between the pigments and cyanotoxins – especially microcystins (MC), and the lack of standardization of the various measurement methods. A dual-model strategy can provide an approach to address these challenges. One model uses either chlorophyll-a (Chl-a) or phycocyanin (PC) collected in situ as a surrogate to estimate the MC concentration. The other uses a remote sensing algorithm to estimate the concentration of the surrogate pigment. Where blooms are mixtures of cyanobacteria and eukaryotic algae, PC should be the preferred surrogate to Chl-a. Where cyanobacteria dominate, Chl-a is a better surrogate than PC for remote sensing. Phycocyanin is less sensitive to detection by optical remote sensing, it is less frequently measured, PC laboratory methods are still not standardized, and PC has greater intracellular variability. Either pigment should not be presumed to have a fixed relationship with MC for any water body. The MC-pigment relationship can be valid over weeks, but have considerable intra- and inter-annual variability due to changes in the amount of MC produced relative to cyanobacterial biomass. To detect pigments by satellite, three classes of algorithms (analytic, semi-analytic, and derivative) have been used. Analytical and semi-analytical algorithms are more sensitive but less robust than derivatives because they depend on accurate atmospheric correction; as a result derivatives are more commonly used. Derivatives can estimate Chl-a concentration, and research suggests they can detect and possibly quantify PC. Derivative algorithms, however, need to be standardized in order to evaluate the reproducibility of parameterizations between lakes. A strategy for producing useful estimates

  14. The effects of commuter pedestrian traffic on the use of stairs in an urban setting.

    Science.gov (United States)

    Andersen, Ross E; Bauman, Adrian E

    2011-01-01

    Most public health physical activity guidelines now encourage people to look for opportunities to accumulate physical activity throughout the day. Climbing stairs in lieu of riding escalators is a prime opportunity to make healthier choices that promote active living. The purpose of this investigation was to examine the effects of pedestrian commuter traffic on choices to ride an escalator, walk up an escalator, or walk up adjacent stairs in a busy urban subway station at rush hour. A total of 9766 commuters were observed by two recorders for a 2.5-hour period during the morning rush hour over 8 weeks as to whether the commuters walked up stairs or rode an adjacent escalator in a subway station. The number of observations per 5-minute block was recorded, and an index of commuter traffic was computed. Demographic information and use of escalators/stairs were also recorded. An urban subway station with a two-flight staircase adjacent to an escalator. Adult commuters travelling to work during the morning rush hour. Physical activity choices were examined in relation to commuter traffic. Demographic information, such as age, race, and weight status, were also considered. A χ(2) analysis was used to examine differences in proportions across variables of interest. Means were compared by using multivariate analysis of variance, and confidence intervals were computed. During the least-heavy commuter traffic period, only 11.2% of commuters chose to walk up the stairs, whereas significantly more did so during moderate 18.7% and high 20.8% commuter traffic periods (χ(2)  =  61.8, p < .001). During low-traffic times, significantly more commuters (21.4%) walked up the escalators compared with moderate-traffic (18.0%) or high-traffic (18.3%) periods. African-American commuters passively rode the escalator more (68.2%) than white commuters (56.7%), and their patterns were less affected by commuter traffic (p < .05). Congestion in public places can have a significant effect

  15. Commutated automatic gain control system

    Science.gov (United States)

    Yost, S. R.

    1982-01-01

    The commutated automatic gain control (AGC) system was designed and built for the prototype Loran-C receiver is discussed. The current version of the prototype receiver, the Mini L-80, was tested initially in 1980. The receiver uses a super jolt microcomputer to control a memory aided phase loop (MAPLL). The microcomputer also controls the input/output, latitude/longitude conversion, and the recently added AGC system. The AGC control adjusts the level of each station signal, such that the early portion of each envelope rise is about at the same amplitude in the receiver envelope detector.

  16. Fractal generator for efficient production of random planar patterns and symbols in digital mapping

    Science.gov (United States)

    Chen, Qiyu; Liu, Gang; Ma, Xiaogang; Li, Xinchuan; He, Zhenwen

    2017-08-01

    In digital cartography, the automatic generation of random planar patterns and symbols is still an ongoing challenge. Those patterns and symbols of randomness have randomly variated configurations and boundaries, and their generating algorithms are constrained by the shape features, cartographic standards and many other conditions. The fractal geometry offers favorable solutions to simulate random boundaries and patterns. In the work presented in this paper, we used both fractal theory and random Iterated Function Systems (IFS) to develop a method for the automatic generation of random planar patterns and symbols. The marshland and the trough cross-bedding patterns were used as two case studies for the implementation of the method. We first analyzed the morphological characteristics of those two planar patterns. Then we designed algorithms and implementation schemes addressing the features of each pattern. Finally, we ran the algorithms to generate the patterns and symbols, and compared them with the requirements of a few digital cartographic standards. The method presented in this paper has already been deployed in a digital mapping system for practical uses. The flexibility of the method also allows it to be reused and/or adapted in various software platforms for digital mapping.

  17. Fractal patterns on the onset of coherent structures in a coupled map lattice

    Indian Academy of Sciences (India)

    G Ambika; Kamala Menon

    2002-07-01

    We report the formation of Cantor set-like fractals during the development of coherent structures in a coupled map lattice (CML). The dependence of these structures on the size of the lattice as well as the first three dimensions of the associated fractal patterns are analyzed numerically.

  18. Mapping Classroom Interactions: A Spatial Approach to Analyzing Patterns of Student Participation

    Science.gov (United States)

    Abbot, Sophia; Cook-Sather, Alison; Hein, Carola

    2014-01-01

    This article explores how mapping patterns of student participation in classroom discussion can both illuminate and complicate the dynamic relationships among identity, physical position in the classroom, student engagement, and course content. It draws on the perspectives of an undergraduate in the role of pedagogical consultant, a faculty member…

  19. Patterning exergy of benthic macroinvertebrate communities using self-organizing maps

    NARCIS (Netherlands)

    Park, Y.S.; Lek, S.; Scardi, M.; Verdonschot, P.F.M.; Jørgensen, S.E.

    2006-01-01

    Exergy is a measure of the free energy of a system with contributions from all components including the energy of organisms, and it is used as an ecological indicator. In this study, we implemented a self-organizing map (SOM) for patterning exergy of benthic macroinvertebrate communities. The datase

  20. Differences in Stakeholder Perceptions about Training Evaluation: A Concept Mapping/Pattern Matching Investigation.

    Science.gov (United States)

    Michalski, Greg V.; Cousins, J. Bradley

    2000-01-01

    Used concept mapping and pattern matching in exploratory research to investigate differences in stakeholder perceptions of training results and evaluation. Group perceptions and the individual perceptions of 39 managers, product developers, and training professionals show that all stakeholder groups agreed reasonably well about the importance of…

  1. mapDamage: testing for damage patterns in ancient DNA sequences.

    Science.gov (United States)

    Ginolhac, Aurelien; Rasmussen, Morten; Gilbert, M Thomas P; Willerslev, Eske; Orlando, Ludovic

    2011-08-01

    Ancient DNA extracts consist of a mixture of contaminant DNA molecules, most often originating from environmental microbes, and endogenous fragments exhibiting substantial levels of DNA damage. The latter introduce specific nucleotide misincorporations and DNA fragmentation signatures in sequencing reads that could be advantageously used to argue for sequence validity. mapDamage is a Perl script that computes nucleotide misincorporation and fragmentation patterns using next-generation sequencing reads mapped against a reference genome. The Perl script outputs are further automatically processed in embedded R script in order to detect typical patterns of genuine ancient DNA sequences. The Perl script mapDamage is freely available with documentation and example files at http://geogenetics.ku.dk/all_literature/mapdamage/. The script requires prior installation of the SAMtools suite and R environment and has been validated on both GNU/Linux and MacOSX operating systems.

  2. Geomorphological mapping in arid regions supported by the analysis of shrub patterns

    Science.gov (United States)

    Hikel, H.; Jarmer, T.; Schwanghart, W.; Kuhn, N. J.; Yair, Y.; Shoshani, M.

    2012-04-01

    Arid and semi-arid areas are often covered by sparse and patchy vegetation with spatial patterns being related to water scarcity. The patterns are governed to a high degree by topography and substrate that in turn reflect prevalent geomorphological and hydrological processes. We hypothesize that this relation can be utilized to support geomorphological mapping in dryland areas. The aim of this study is to develop an approach towards automated geomorphological mapping in drylands at the hillslope scale. Geomorphological mapping was carried out at the experimental catchment site nearby Sede Boqer, Israel, along two hillslope transects. Twenty rectangular plots were surveyed to determine the percent vegetation cover. A ground based hyperspectral camera was used to image the transects with a spatial resolution of 0.05 cm. Plant canopy was obtained using a supervised classification. In addition, an aerial photo with a spatial resolution of 0.5 m was utilize to map plants at a larger spatial extent. Both datasets were used to calculate spatial pattern indices such as vegetation density, lacunarity, bare area fragmentation index and patch upslope side length/area ratio. All indices were investigated regarding their scale invariance with respect to the differently resolved datasets. Indices with a high degree of explanatory power and scale invariance were then used as variables in a decision tree model for automated geomorphological mapping. Preliminary results indicate that the spatial pattern indices can be used as an identification tool of geomorphological units and ecohydrological environments. The result suggests that geomorphological mapping in arid and semi-arid areas can be supported by vegetation detection using remote sensing and digital image processing.

  3. On Polynomial Functions over Finite Commutative Rings

    Institute of Scientific and Technical Information of China (English)

    Jian Jun JIANG; Guo Hua PENG; Qi SUN; Qi Fan ZHANG

    2006-01-01

    Let R be an arbitrary finite commutative local ring. In this paper, we obtain a necessary and sufficient condition for a function over R to be a polynomial function. Before this paper, necessary and sufficient conditions for a function to be a polynomial function over some special finite commutative local rings were obtained.

  4. Commutativity and ideals in category crossed products

    DEFF Research Database (Denmark)

    Öinert, Per Johan; Lundström, Patrik

    2010-01-01

    In order to simultaneously generalize matrix rings and group graded crossed products, we introduce category crossed products. For such algebras we describe the centre and the commutant of the coefficient ring. We also investigate the connection between on the one hand maximal commutativity of the...

  5. On Non-commutative Geodesic Motion

    CERN Document Server

    Ulhoa, S C; Santos, A F

    2013-01-01

    In this work we study the geodesic motion on a noncommutative space-time. As a result we find a non-commutative geodesic equation and then we derive corrections of the deviation angle per revolution in terms of the non-commutative parameter when we specify the problem of Mercury's perihelion. In this way, we estimate the noncommutative parameter based in experimental data.

  6. On non-commutative geodesic motion

    Science.gov (United States)

    Ulhoa, S. C.; Amorim, R. G. G.; Santos, A. F.

    2014-07-01

    In this work we study the geodesic motion on a noncommutative space-time. As a result we find a non-commutative geodesic equation and then we derive corrections of the deviation angle per revolution in terms of the non-commutative parameter when we specify the problem of Mercury's perihelion. In this way, we estimate the noncommutative parameter based in experimental data.

  7. Happiness and Satisfaction with Work Commute

    Science.gov (United States)

    Olsson, Lars E.; Garling, Tommy; Ettema, Dick; Friman, Margareta; Fujii, Satoshi

    2013-01-01

    Research suggests that for many people happiness is being able to make the routines of everyday life work, such that positive feelings dominate over negative feelings resulting from daily hassles. In line with this, a survey of work commuters in the three largest urban areas of Sweden show that satisfaction with the work commute contributes to…

  8. Determinants of self-employment among commuters and non-commuters

    DEFF Research Database (Denmark)

    Backman, M.; Karlsson, C.

    2016-01-01

    We analyse the determinants of self-employment and focus on the contextual environment. By distinguishing between commuters and non-commuters we are able to analyse the influence from the work and home environment, respectively. Our results indicate a significant difference between non-commuters ......We analyse the determinants of self-employment and focus on the contextual environment. By distinguishing between commuters and non-commuters we are able to analyse the influence from the work and home environment, respectively. Our results indicate a significant difference between non......-commuters and commuters in terms of the role of networks for becoming self-employed. Our results indicate that it is the business networks where people work, rather than where they live that exerts a positive influence on the probability of becoming self-employed. These effects are further robust over educational...

  9. Geomorphons — a pattern recognition approach to classification and mapping of landforms

    Science.gov (United States)

    Jasiewicz, Jarosław; Stepinski, Tomasz F.

    2013-01-01

    We introduce a novel method for classification and mapping of landform elements from a DEM based on the principle of pattern recognition rather than differential geometry. At the core of the method is the concept of geomorphon (geomorphologic phonotypes) — a simple ternary pattern that serves as an archetype of a particular terrain morphology. A finite number of 498 geomorphons constitute a comprehensive and exhaustive set of all possible morphological terrain types including standard elements of landscape, as well as unfamiliar forms rarely found in natural terrestrial surfaces. A single scan of a DEM assigns an appropriate geomorphon to every cell in the raster using a procedure that self-adapts to identify the most suitable spatial scale at each location. As a result, the method classifies landform elements at a range of different spatial scales with unprecedented computational efficiency. A general purpose geomorphometric map — an interpreted map of topography — is obtained by generalizing allgeomorphons to a small number of the most common landform elements. Due to the robustness and high computational efficiency of the method high resolution geomorphometric maps having continental and even global extents can be generated from giga-cell DEMs. Such maps are a valuable new resource for both manual and automated geomorphometric analyses. In order to demonstrate a practical application of this new method, a 30 m cell- 1 geomorphometric map of the entire country of Poland is generated and the features and potential usage of this map are briefly discussed. The computer implementation of the method is outlined. The code is available in the public domain.

  10. Multiplicative equations over commuting matrices

    Energy Technology Data Exchange (ETDEWEB)

    Babai, L. [Univ. of Chicago, IL (United States)]|[Eotvos Univ., Budapest (Hungary); Beals, R. [Rutgers Univ., Piscataway, NJ (United States); Cai, Jin-Yi [SUNY, Buffalo, NY (United States)] [and others

    1996-12-31

    We consider the solvability of the equation and generalizations, where the A{sub i} and B are given commuting matrices over an algebraic number field F. In the semigroup membership problem, the variables x{sub i} are constrained to be nonnegative integers. While this problem is NP-complete for variable k, we give a polynomial time algorithm if k is fixed. In the group membership problem, the matrices are assumed to be invertible, and the variables x{sub i} may take on negative values. In this case we give a polynomial time algorithm for variable k and give an explicit description of the set of all solutions (as an affine lattice). The special case of 1 x 1 matrices was recently solved by Guoqiang Ge; we heavily rely on his results.

  11. Weaving commutators: beyond Fock space

    CERN Document Server

    Arzano, Michele

    2012-01-01

    The symmetrization postulate and the associated Bose/Fermi (anti)-commutators for field mode operators are among the pillars on which local quantum field theory lays its foundations. They ultimately determine the structure of Fock space and are closely connected with the local properties of the fields and with the action of symmetry generators on observables and states. We here show that the quantum field theory describing relativistic particles coupled to three dimensional Einstein gravity as a topological defect must be constructed using a deformed algebra of creation and annihilation operators. This reflects a non-trivial group manifold structure of the classical momentum space and a modification of the Leibniz rule for the action of symmetry generators governed by Newton's constant. We outline various arguments suggesting that, at least at the qualitative level, these three-dimensional results could also apply to real four-dimensional world thus forcing us to re-think the ordinary multiparticle structure ...

  12. Twisted rings and moduli stacks of "fat" point modules in non-commutative projective geometry

    CERN Document Server

    Chan, Daniel

    2010-01-01

    The Hilbert scheme of point modules was introduced by Artin-Tate-Van den Bergh to study non-commutative graded algebras. The key tool is the construction of a map from the algebra to a twisted ring on this Hilbert scheme. In this paper, we study moduli stacks of more general "fat" point modules, and show that there is a similar map to a twisted ring associated to the stack. This is used to provide a sufficient criterion for a non-commutative projective surface to be birationally PI. It is hoped that such a criterion will be useful in understanding Mike Artin's conjecture on the birational classification of non-commutative surfaces.

  13. Fostering Formal Commutativity Knowledge with Approximate Arithmetic.

    Directory of Open Access Journals (Sweden)

    Sonja Maria Hansen

    Full Text Available How can we enhance the understanding of abstract mathematical principles in elementary school? Different studies found out that nonsymbolic estimation could foster subsequent exact number processing and simple arithmetic. Taking the commutativity principle as a test case, we investigated if the approximate calculation of symbolic commutative quantities can also alter the access to procedural and conceptual knowledge of a more abstract arithmetic principle. Experiment 1 tested first graders who had not been instructed about commutativity in school yet. Approximate calculation with symbolic quantities positively influenced the use of commutativity-based shortcuts in formal arithmetic. We replicated this finding with older first graders (Experiment 2 and third graders (Experiment 3. Despite the positive effect of approximation on the spontaneous application of commutativity-based shortcuts in arithmetic problems, we found no comparable impact on the application of conceptual knowledge of the commutativity principle. Overall, our results show that the usage of a specific arithmetic principle can benefit from approximation. However, the findings also suggest that the correct use of certain procedures does not always imply conceptual understanding. Rather, the conceptual understanding of commutativity seems to lag behind procedural proficiency during elementary school.

  14. Fertility and Commuting Behaviour in Germany

    Directory of Open Access Journals (Sweden)

    Johannes Huinink

    2012-12-01

    Firstly, a cross-sectional, multivariate probit-regression (with correlated errors on the intention to have a child within two years, on being childless and on medium- and long- distance commuting is applied. The model shows no significant correlation between commuting and the intention to have a child; it does however show a correlation between medium- and long distance commuting and the probability of women to be childless. Secondly, a longitudinal difference model on changing fertility intentions between panel wave 1 and wave 3 is estimated. For women, a positive effect can be found of interrupting medium- and long-distance commuting or, surprisingly, continuing medium- and long-distance commuting on the intention to have a child within two years. Thirdly, for men and women who reported a fertility intention in the first wave, a longitudinal Heckman-selection probit-regression on the probability of having a child between wave 1 and wave 3 is estimated. It shows negative effects of medium- and long-distance commuting on having a child. Taken together, these findings support the assumption that commuting plays a characteristically different role in different phases of the fertility-related decision process.

  15. The theory of finitely generated commutative semigroups

    CERN Document Server

    Rédei, L; Stark, M; Gravett, K A H

    1966-01-01

    The Theory of Finitely Generated Commutative Semigroups describes a theory of finitely generated commutative semigroups which is founded essentially on a single """"fundamental theorem"""" and exhibits resemblance in many respects to the algebraic theory of numbers. The theory primarily involves the investigation of the F-congruences (F is the the free semimodule of the rank n, where n is a given natural number). As applications, several important special cases are given. This volume is comprised of five chapters and begins with preliminaries on finitely generated commutative semigroups before

  16. Application of self-organizing maps in compounds pattern recognition and combinatorial library design.

    Science.gov (United States)

    Yan, Aixia

    2006-07-01

    In the computer-aided drug design, in order to find some new leads from a large library of compounds, the pattern recognition study of the diversity and similarity assessment of the chemical compounds is required; meanwhile in the combinatorial library design, more attention is given to design target focusing library along with diversity and drug-likeness criteria. This review presents the current state-of-art applications of Kohonen self-organizing maps (SOM) for studying the compounds pattern recognition, comparing the property of molecular surfaces, distinguishing drug-like and nondrug-like molecules, splitting a dataset into the proper training and test sets before constructing a QSAR (Quantitative Structural-Activity Relationship) model, and also for the combinatorial libraries comparison and the combinatorial library design. The Kohonen self-organizing map will continue to play an important role in drug discovery and library design.

  17. On the interrelations between migration and commuting

    Directory of Open Access Journals (Sweden)

    Lukić Vesna

    2013-01-01

    Full Text Available In this paper, we emphasise the significance of studying the interrelations between commuting and migration. The aim of the paper is to point out the factors which affect these interrelations (demographic and socio-economic characteristics of migrants and commuters, labour market, real estate market, information, life style, etc., with the special emphasis on the role of commuting distance onto the chosen mobility type. Besides theorethical frameworks and results of the selected foreign researches up to date, the overview of research of interrelations between migration and commuting in Serbia has also been presented. While earlier studies conducted by Gawryszenski (1978, Termote (1980 and Reitsma&Vergoossen (1987 pointed to the replacement of migration types between each other within country, in recent literature the interaction between migration and commuting has been studied in a trans-boundary context of the contemporary EU. Modern trend of long distance commuting instead of migration and the concept of substitution/replacement regarding migration and commuting have also been discussed. In Serbia, there is a positive correlation between commuting outflows and immigration in rural settlements of Vojvodina province. Namely, commuting and migration are complement, which is the characteristic of both processes sub-urbanisation and ex-urbanisation (Lukić, 2012. In addition to ownership of real estate and previous migration experience, marital status influenced the chosen mobility type in Serbia as well. Adjustment to changes of Serbian labour market is mostly conducted via migration (Miletić, Lukić, Miljanović, 2011. Interrelations between migration and commuting are very significant due to the tendency of transformation of some commuters into migrants. This process has its consequences, both on demographic as well as the overall socio-economic development of the area of commuters’ origin and destination. However, even though the surveys

  18. Comparison of CT-derived ventilation maps with deposition patterns of inhaled microspheres in rats

    Science.gov (United States)

    Jacob, Richard E.; Lamm, Wayne J.; Einstein, Daniel R.; Krueger, Melissa A.; Glenny, Robb W.; Corley, Richard A.

    2016-01-01

    Purpose Computer models for inhalation toxicology and drug-aerosol delivery studies rely on ventilation pattern inputs for predictions of particle deposition and vapor uptake. However, changes in lung mechanics due to disease can impact airflow dynamics and model results. It has been demonstrated that non-invasive, in vivo, 4DCT imaging (3D imaging at multiple time points in the breathing cycle) can be used to map heterogeneities in ventilation patterns under healthy and disease conditions. The purpose of this study was to validate ventilation patterns measured from CT imaging by exposing the same rats to an aerosol of fluorescent microspheres (FMS) and examining particle deposition patterns using cryomicrotome imaging. Materials and Methods Six male Sprague-Dawley rats were intratracheally instilled with elastase to a single lobe to induce a heterogeneous disease. After four weeks, rats were imaged over the breathing cycle by CT then immediately exposed to an aerosol of ~1μm FMS for ~5 minutes. After the exposure, the lungs were excised and prepared for cryomicrotome imaging, where a 3D image of FMS deposition was acquired using serial sectioning. Cryomicrotome images were spatially registered to match the live CT images to facilitate direct quantitative comparisons of FMS signal intensity with the CT-based ventilation maps. Results Comparisons of fractional ventilation in contiguous, non-overlapping, 3D regions between CT-based ventilation maps and FMS images showed strong correlations in fractional ventilation (r=0.888, p<0.0001). Conclusion We conclude that ventilation maps derived from CT imaging are predictive of the 1μm aerosol deposition used in ventilation-perfusion heterogeneity inhalation studies. PMID:25513951

  19. Comparison of CT-derived Ventilation Maps with Deposition Patterns of Inhaled Microspheres in Rats

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Rick E.; Lamm, W. J.; Einstein, Daniel R.; Krueger, Melissa; Glenny, Robb W.; Corley, Richard A.

    2015-04-01

    Purpose: Computer models for inhalation toxicology and drug-aerosol delivery studies rely on ventilation pattern inputs for predictions of particle deposition and vapor uptake. However, changes in lung mechanics due to disease can impact airflow dynamics and model results. It has been demonstrated that non-invasive, in vivo, 4DCT imaging (3D imaging at multiple time points in the breathing cycle) can be used to map heterogeneities in ventilation patterns under healthy and disease conditions. The purpose of this study was to validate ventilation patterns measured from CT imaging by exposing the same rats to an aerosol of fluorescent microspheres (FMS) and examining particle deposition patterns using cryomicrotome imaging. Materials and Methods: Six male Sprague-Dawley rats were intratracheally instilled with elastase to a single lobe to induce a heterogeneous disease. After four weeks, rats were imaged over the breathing cycle by CT then immediately exposed to an aerosol of ~1µm FMS for ~5 minutes. After the exposure, the lungs were excised and prepared for cryomicrotome imaging, where a 3D image of FMS deposition was acquired using serial sectioning. Cryomicrotome images were spatially registered to match the live CT images to facilitate direct quantitative comparisons of FMS signal intensity with the CT-based ventilation maps. Results: Comparisons of fractional ventilation in contiguous, non-overlapping, 3D regions between CT-based ventilation maps and FMS images showed strong correlations in fractional ventilation (r=0.888, p<0.0001). Conclusion: We conclude that ventilation maps derived from CT imaging are predictive of the 1µm aerosol deposition used in ventilation-perfusion heterogeneity inhalation studies.

  20. Apriori Versions Based on MapReduce for Mining Frequent Patterns on Big Data.

    Science.gov (United States)

    Luna, Jose Maria; Padillo, Francisco; Pechenizkiy, Mykola; Ventura, Sebastian

    2017-09-27

    Pattern mining is one of the most important tasks to extract meaningful and useful information from raw data. This task aims to extract item-sets that represent any type of homogeneity and regularity in data. Although many efficient algorithms have been developed in this regard, the growing interest in data has caused the performance of existing pattern mining techniques to be dropped. The goal of this paper is to propose new efficient pattern mining algorithms to work in big data. To this aim, a series of algorithms based on the MapReduce framework and the Hadoop open-source implementation have been proposed. The proposed algorithms can be divided into three main groups. First, two algorithms [Apriori MapReduce (AprioriMR) and iterative AprioriMR] with no pruning strategy are proposed, which extract any existing item-set in data. Second, two algorithms (space pruning AprioriMR and top AprioriMR) that prune the search space by means of the well-known anti-monotone property are proposed. Finally, a last algorithm (maximal AprioriMR) is also proposed for mining condensed representations of frequent patterns. To test the performance of the proposed algorithms, a varied collection of big data datasets have been considered, comprising up to 3 · 10#x00B9;⁸ transactions and more than 5 million of distinct single-items. The experimental stage includes comparisons against highly efficient and well-known pattern mining algorithms. Results reveal the interest of applying MapReduce versions when complex problems are considered, and also the unsuitability of this paradigm when dealing with small data.

  1. Encoding Phases using Commutativity and Non-commutativity in a Logical Framework

    CERN Document Server

    Amblard, Maxime

    2011-01-01

    This article presents an extension of Minimalist Categorial Gram- mars (MCG) to encode Chomsky's phases. These grammars are based on Par- tially Commutative Logic (PCL) and encode properties of Minimalist Grammars (MG) of Stabler. The first implementation of MCG were using both non- commutative properties (to respect the linear word order in an utterance) and commutative ones (to model features of different constituents). Here, we pro- pose to adding Chomsky's phases with the non-commutative tensor product of the logic. Then we could give account of the PIC just by using logical prop- erties of the framework.

  2. Chiral bosonization for non-commutative fields

    CERN Document Server

    Das, A; Méndez, F; López-Sarrion, J; Das, Ashok; Gamboa, Jorge; M\\'endez, Fernando; L\\'opez-Sarri\\'on, Justo

    2004-01-01

    A model of chiral bosons on a non-commutative field space is constructed and new generalized bosonization (fermionization) rules for these fields are given. The conformal structure of the theory is characterized by a level of the Kac-Moody algebra equal to $(1+ \\theta^2)$ where $\\theta$ is the non-commutativity parameter and chiral bosons living in a non-commutative fields space are described by a rational conformal field theory with the central charge of the Virasoro algebra equal to 1. The non-commutative chiral bosons are shown to correspond to a free fermion moving with a speed equal to $ c^{\\prime} = c \\sqrt{1+\\theta^2} $ where $c$ is the speed of light. Lorentz invariance remains intact if $c$ is rescaled by $c \\to c^{\\prime}$. The dispersion relation for bosons and fermions, in this case, is given by $\\omega = c^{\\prime} | k|$.

  3. Covariant non-commutative space–time

    Directory of Open Access Journals (Sweden)

    Jonathan J. Heckman

    2015-05-01

    Full Text Available We introduce a covariant non-commutative deformation of 3+1-dimensional conformal field theory. The deformation introduces a short-distance scale ℓp, and thus breaks scale invariance, but preserves all space–time isometries. The non-commutative algebra is defined on space–times with non-zero constant curvature, i.e. dS4 or AdS4. The construction makes essential use of the representation of CFT tensor operators as polynomials in an auxiliary polarization tensor. The polarization tensor takes active part in the non-commutative algebra, which for dS4 takes the form of so(5,1, while for AdS4 it assembles into so(4,2. The structure of the non-commutative correlation functions hints that the deformed theory contains gravitational interactions and a Regge-like trajectory of higher spin excitations.

  4. A Universal Model of Commuting Networks

    CERN Document Server

    Lenormand, Maxime; Gargiulo, Floriana; Deffuant, Guillaume

    2012-01-01

    We test a recently proposed model of commuting networks on 80 case studies from different regions of the world (Europe and United-States) and with geographic units of different sizes (municipality, county, region). The model takes as input the number of commuters coming in and out of each geographic unit and generates the matrix of commuting flows betwen the geographic units. We show that the single parameter of the model, which rules the compromise between the influence of the distance and job opportunities, follows a universal law that depends only on the average surface of the geographic units. We verified that the law derived from a part of the case studies yields accurate results on other case studies. We also show that our model significantly outperforms the two other approaches proposing a universal commuting model (Balcan et al. (2009); Simini et al. (2012)), particularly when the geographic units are small (e.g. municipalities).

  5. Foundations of commutative rings and their modules

    CERN Document Server

    Wang, Fanggui

    2016-01-01

    This book provides an introduction to the basics and recent developments of commutative algebra. A glance at the contents of the first five chapters shows that the topics covered are ones that usually are included in any commutative algebra text. However, the contents of this book differ significantly from most commutative algebra texts: namely, its treatment of the Dedekind–Mertens formula, the (small) finitistic dimension of a ring, Gorenstein rings, valuation overrings and the valuative dimension, and Nagata rings. Going further, Chapter 6 presents w-modules over commutative rings as they can be most commonly used by torsion theory and multiplicative ideal theory. Chapter 7 deals with multiplicative ideal theory over integral domains. Chapter 8 collects various results of the pullbacks, especially Milnor squares and D+M constructions, which are probably the most important example-generating machines. In Chapter 9, coherent rings with finite weak global dimensions are probed, and the local ring of weak gl...

  6. On nth commutativity degree of some 3-Engel groups

    Science.gov (United States)

    Yahya, Zainab; Mohd Ali, Nor Muhainiah; Sarmin, Nor Haniza; Sabani, Muhammad Syafiq; Zakaria, Mardhiah

    2013-04-01

    This paper focuses on some 3-Engel groups. Suppose x and y are elements of a group G. The commutativity degree of a group is the probability that two elements in the group commute and is denoted by P(G). Meanwhile, the nth commutativity degree of a group G is the probability that for any pairs of x and y in G, xn and y commute. In this paper, the nth commutativity degree of some 3-Engel groups is determined.

  7. New commutation relations for quantum gravity

    CERN Document Server

    Soo, Chopin

    2016-01-01

    A new set of fundamental commutation relations for quantum gravity is presented. The basic variables are the eight components of the unimodular part of the spatial dreibein and eight SU(3) generators which correspond to Klauder's momentric variables. The commutation relations are not canonical, but they have well defined group theoretical meanings. All fundamental entities are dimensionless; and quantum wave functionals are preferentially selected to be in the dreibein representation.

  8. Non-commutative standard model: model building

    CERN Document Server

    Chaichian, Masud; Presnajder, P

    2003-01-01

    A non-commutative version of the usual electro-weak theory is constructed. We discuss how to overcome the two major problems: (1) although we can have non-commutative U(n) (which we denote by U sub * (n)) gauge theory we cannot have non-commutative SU(n) and (2) the charges in non-commutative QED are quantized to just 0,+-1. We show how the latter problem with charge quantization, as well as with the gauge group, can be resolved by taking the U sub * (3) x U sub * (2) x U sub * (1) gauge group and reducing the extra U(1) factors in an appropriate way. Then we proceed with building the non-commutative version of the standard model by specifying the proper representations for the entire particle content of the theory, the gauge bosons, the fermions and Higgs. We also present the full action for the non-commutative standard model (NCSM). In addition, among several peculiar features of our model, we address the inherentCP violation and new neutrino interactions. (orig.)

  9. Determining Commuting Behaviour from Monitoring Technologies

    Directory of Open Access Journals (Sweden)

    Yuting You

    2015-01-01

    Full Text Available The study of commuting behaviour has always been one significant focus of people to reach comprehensive knowledge of transport-related scenarios. Similarly, commuting behaviour, as one of the four major physical activities people engaged in during daily life, gained much attention in aspect of health fields. This paper, with the sample data collected by The Australian Diabetes, Obesity and Lifestyle (AusDiab study, discusses the process of how to utilize data obtained from GPS and inclinometer device, along with basic information about participants to conduct travel survey, and reconstructing participant's commuting behaviour. In the analyses of the sample, the procedure of datasets integration through DELPHI programming and protocols established to determine corresponding commuting behaviour are discussed. The details of commuting behaviour illustrated in this study included travel mode, travel duration, allocation of trip stages, and corresponding level of physical activities. This paper discusses a promise for applying advanced technologies in travel survey instead of traditional ones in terms of accuracy and reliability; it discusses the feasibility to discover the coherent relationship between health outcome and commuting behaviour from travel-tracking technologies.

  10. Mapping National Plant Biodiversity Patterns in South Korea with the MARS Species Distribution Model.

    Directory of Open Access Journals (Sweden)

    Hyeyeong Choe

    Full Text Available Accurate information on the distribution of existing species is crucial to assess regional biodiversity. However, data inventories are insufficient in many areas. We examine the ability of Multivariate Adaptive Regression Splines (MARS multi-response species distribution model to overcome species' data limitations and portray plant species distribution patterns for 199 South Korean plant species. The study models species with two or more observations, examines their contribution to national patterns of species richness, provides a sensitivity analysis of different range threshold cutoff approaches for modeling species' ranges, and presents considerations for species modeling at fine spatial resolution. We ran MARS models for each species and tested four threshold methods to transform occurrence probabilities into presence or absence range maps. Modeled occurrence probabilities were extracted at each species' presence points, and the mean, median, and one standard deviation (SD calculated to define data-driven thresholds. A maximum sum of sensitivity and specificity threshold was also calculated, and the range maps from the four cutoffs were tested using independent plant survey data. The single SD values were the best threshold tested for minimizing omission errors and limiting species ranges to areas where the associated occurrence data were correctly classed. Eight individual species range maps for rare plant species were identified that are potentially affected by resampling predictor variables to fine spatial scales. We portray spatial patterns of high species richness by assessing the combined range maps from three classes of species: all species, endangered and endemic species, and range-size rarity of all species, which could be used in conservation planning for South Korea. The MARS model is promising for addressing the common problem of few species occurrence records. However, projected species ranges are highly dependent on the

  11. Mapping National Plant Biodiversity Patterns in South Korea with the MARS Species Distribution Model.

    Science.gov (United States)

    Choe, Hyeyeong; Thorne, James H; Seo, Changwan

    2016-01-01

    Accurate information on the distribution of existing species is crucial to assess regional biodiversity. However, data inventories are insufficient in many areas. We examine the ability of Multivariate Adaptive Regression Splines (MARS) multi-response species distribution model to overcome species' data limitations and portray plant species distribution patterns for 199 South Korean plant species. The study models species with two or more observations, examines their contribution to national patterns of species richness, provides a sensitivity analysis of different range threshold cutoff approaches for modeling species' ranges, and presents considerations for species modeling at fine spatial resolution. We ran MARS models for each species and tested four threshold methods to transform occurrence probabilities into presence or absence range maps. Modeled occurrence probabilities were extracted at each species' presence points, and the mean, median, and one standard deviation (SD) calculated to define data-driven thresholds. A maximum sum of sensitivity and specificity threshold was also calculated, and the range maps from the four cutoffs were tested using independent plant survey data. The single SD values were the best threshold tested for minimizing omission errors and limiting species ranges to areas where the associated occurrence data were correctly classed. Eight individual species range maps for rare plant species were identified that are potentially affected by resampling predictor variables to fine spatial scales. We portray spatial patterns of high species richness by assessing the combined range maps from three classes of species: all species, endangered and endemic species, and range-size rarity of all species, which could be used in conservation planning for South Korea. The MARS model is promising for addressing the common problem of few species occurrence records. However, projected species ranges are highly dependent on the threshold and scale

  12. Commutator coverings of Siegel threefolds

    CERN Document Server

    Gritsenko, V

    1997-01-01

    We investigate the existence and non-existence of modular forms of low weight with a character with respect to the paramodular group $\\Gamma_t$ and discuss the resulting geometric consequences. Using an advanced version of Maa\\ss\\ lifting one can construct many examples of such modular forms and in particular examples of weight 3 cusp forms. Consequently we find many abelian coverings of low degree of the moduli space ${\\Cal A}_t$ of (1,t)-polarized abelian surfaces which are not unirational. We also determine the commutator subgroups of the paramodular group $\\Gamma_t$ and its degree 2 extension $\\Gamma^+_t$. This has applications for the Picard group of the moduli stack ${\\underline{\\Cal A}}_t$. Finally we prove non-existence theorems for low weight modular forms. As one of our main results we obtain the theorem that the maximal abelian cover ${\\Cal A}_t^{com}$ of ${\\Cal A}_t$ has geometric genus 0 if and only if t=1, 2, 4 or 5. We also prove that ${\\Cal A}_t^{com}$ has geometric genus 1 for t=3 and 7.

  13. A framework for mining actionable navigation patterns from in-store RFID datasets via indoor mapping.

    Science.gov (United States)

    Shen, Bin; Zheng, Qiuhua; Li, Xingsen; Xu, Libo

    2015-03-05

    With the quick development of RFID technology and the decreasing prices of RFID devices, RFID is becoming widely used in various intelligent services. Especially in the retail application domain, RFID is increasingly adopted to capture the shopping tracks and behavior of in-store customers. To further enhance the potential of this promising application, in this paper, we propose a unified framework for RFID-based path analytics, which uses both in-store shopping paths and RFID-based purchasing data to mine actionable navigation patterns. Four modules of this framework are discussed, which are: (1) mapping from the physical space to the cyber space, (2) data preprocessing, (3) pattern mining and (4) knowledge understanding and utilization. In the data preprocessing module, the critical problem of how to capture the mainstream shopping path sequences while wiping out unnecessary redundant and repeated details is addressed in detail. To solve this problem, two types of redundant patterns, i.e., loop repeat pattern and palindrome-contained pattern are recognized and the corresponding processing algorithms are proposed. The experimental results show that the redundant pattern filtering functions are effective and scalable. Overall, this work builds a bridge between indoor positioning and advanced data mining technologies, and provides a feasible way to study customers' shopping behaviors via multi-source RFID data.

  14. A Framework for Mining Actionable Navigation Patterns from In-Store RFID Datasets via Indoor Mapping

    Directory of Open Access Journals (Sweden)

    Bin Shen

    2015-03-01

    Full Text Available With the quick development of RFID technology and the decreasing prices of RFID devices, RFID is becoming widely used in various intelligent services. Especially in the retail application domain, RFID is increasingly adopted to capture the shopping tracks and behavior of in-store customers. To further enhance the potential of this promising application, in this paper, we propose a unified framework for RFID-based path analytics, which uses both in-store shopping paths and RFID-based purchasing data to mine actionable navigation patterns. Four modules of this framework are discussed, which are: (1 mapping from the physical space to the cyber space, (2 data preprocessing, (3 pattern mining and (4 knowledge understanding and utilization. In the data preprocessing module, the critical problem of how to capture the mainstream shopping path sequences while wiping out unnecessary redundant and repeated details is addressed in detail. To solve this problem, two types of redundant patterns, i.e., loop repeat pattern and palindrome-contained pattern are recognized and the corresponding processing algorithms are proposed. The experimental results show that the redundant pattern filtering functions are effective and scalable. Overall, this work builds a bridge between indoor positioning and advanced data mining technologies, and provides a feasible way to study customers’ shopping behaviors via multi-source RFID data.

  15. First Simulation Results for the Photon in a Non-Commutative Space

    CERN Document Server

    Bietenholz, W; Nishimura, J; Susaki, Y; Volkholz, J

    2005-01-01

    We present preliminary simulation results for QED in a non-commutative 4d space-time, which is discretized to a fuzzy lattice. Its numerical treatment becomes feasible after its mapping onto a dimensionally reduced twisted Eguchi-Kawai matrix model. In this formulation we investigate the Wilson loops and in particular the Creutz ratios. This is an ongoing project which aims at non-perturbative predictions for the photon, which can be confronted with phenomenology in order to verify the possible existence of non-commutativity in nature.

  16. Fertility and Commuting Behaviour in Germany

    Directory of Open Access Journals (Sweden)

    Johannes Huinink

    2012-12-01

    Full Text Available Fertility behaviour is closely related to other dimensions of the individual life course, which are strongly interrelated themselves. Regarding the impact of job-related spatial mobility, empirical findings show a negative correlation between having children and commuting, particularly for women. Up to now, fertility intentions have not been thoroughly investigated in this respect. Longitudinal studies are lacking, too. In this paper, the effects of commuting arrangements of men and women on the intention of having a child within the next two years as well as the probability of realising this intention are addressed. The assumption is, that after accounting for other important factors (employment status, level of qualification, type of consensual union, number of children, residential mobility, medium- and long-distance commuting is negatively related to the fertility intention of women and its realisation. For men, effects are assumed to be nonexistent or even slightly positive. Longitudinal data from the first three waves of the German “Panel Analysis of Intimate Relationships and Family Dynamics” (pairfam are used to test the hypotheses. Firstly, a cross-sectional, multivariate probit-regression (with correlated errors on the intention to have a child within two years, on being childless and on medium- and long- distance commuting is applied. The model shows no significant correlation between commuting and the intention to have a child; it does however show a correlation between medium- and long distance commuting and the probability of women to be childless. Secondly, a longitudinal difference model on changing fertility intentions between panel wave 1 and wave 3 is estimated. For women, a positive effect can be found of interrupting medium- and long-distance commuting or, surprisingly, continuing medium- and long-distance commuting on the intention to have a child within two years. Thirdly, for men and women who reported a fertility

  17. Excess Commuting in Transitional Urban China: A Case Study of Guangzhou

    Institute of Scientific and Technical Information of China (English)

    LIU Wangbao; HOU Quan

    2016-01-01

    During the reform era,Chinese cities witnessed dramatic institutional transformation and spatial restructuring in general and profound change of commuting patterns in particular.Using household surveys collected in Guangzhou,China,in 2001,2005 and 2010,excess commuting measurements are estimated.Excess commuting shows an overall trend of increasing during 1990-1999,and then declining during 2000-2010.We argue that deepening marketization of the jobs and housing sectors has induced spatial separation of jobs and housing.In other words,institutional transition and urban spatial restructuring are underpinning the changes of commuting patterns in Chinese cities.Excess commuting has strong relationship with individual socio-demographic status,which is by and large due to the increasing flexibilities of jobs and housing location choices enjoyed by urban residents.The findings call for considerations on balancing jobs-housing in making public policies relevant to urban development in general,and land use and transportation in particular.

  18. Application of approximate pattern matching in two dimensional spaces to grid layout for biochemical network maps.

    Directory of Open Access Journals (Sweden)

    Kentaro Inoue

    Full Text Available BACKGROUND: For visualizing large-scale biochemical network maps, it is important to calculate the coordinates of molecular nodes quickly and to enhance the understanding or traceability of them. The grid layout is effective in drawing compact, orderly, balanced network maps with node label spaces, but existing grid layout algorithms often require a high computational cost because they have to consider complicated positional constraints through the entire optimization process. RESULTS: We propose a hybrid grid layout algorithm that consists of a non-grid, fast layout (preprocessor algorithm and an approximate pattern matching algorithm that distributes the resultant preprocessed nodes on square grid points. To demonstrate the feasibility of the hybrid layout algorithm, it is characterized in terms of the calculation time, numbers of edge-edge and node-edge crossings, relative edge lengths, and F-measures. The proposed algorithm achieves outstanding performances compared with other existing grid layouts. CONCLUSIONS: Use of an approximate pattern matching algorithm quickly redistributes the laid-out nodes by fast, non-grid algorithms on the square grid points, while preserving the topological relationships among the nodes. The proposed algorithm is a novel use of the pattern matching, thereby providing a breakthrough for grid layout. This application program can be freely downloaded from http://www.cadlive.jp/hybridlayout/hybridlayout.html.

  19. Recurrence quantification analysis applied to spatiotemporal pattern analysis in high-density mapping of human atrial fibrillation

    NARCIS (Netherlands)

    Zeemering, Stef; Bonizzi, Pietro; Maesen, Bart; Peeters, Ralf; Schotten, Ulrich

    2015-01-01

    Spatiotemporal complexity of atrial fibrillation (AF) patterns is often quantified by annotated intracardiac contact mapping. We introduce a new approach that applies recurrence plot (RP) construction followed by recurrence quantification analysis (RQA) to epicardial atrial electrograms, recorded wi

  20. Mapping the irrigated rice cropping patterns of the Mekong delta, Vietnam, through hyper - temporal SPOT NDVI image analysis

    NARCIS (Netherlands)

    Nguyen, T.T.H.; Bie, de C.A.J.M.; Ali, A.; Smaling, E.M.A.

    2012-01-01

    Successful identification and mapping of different cropping patterns under cloudy conditions of a specific crop through remote sensing provides important baseline information for planning and monitoring. In Vietnam, this information is either missing or unavailable; several ongoing projects studying

  1. Mapping the irrigated rice cropping patterns of the Mekong delta, Vietnam through hyper-temporal SPOT NDVI image analysis

    NARCIS (Netherlands)

    Nguyen, Thi Thu Ha; Bie, de C.A.J.M.; Ali, A.; Smaling, E.M.A.; Hoanh, C.T.

    2012-01-01

    Successful identification and mapping of different cropping patterns under cloudy conditions of a specific crop through remote sensing provides important baseline information for planning and monitoring. In Vietnam, this information is either missing or unavailable; several ongoing projects studying

  2. A non-perturbative study of non-commutative U(1) gauge theory

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, J. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan)]|[Graduate Univ. for Advanced Studies (SOKENDAI), Tsukuba (Japan). Dept. of Particle and Nuclear Physics; Bietenholz, W. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Susaki, Y. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan)]|[Tsukuba Univ. (Japan). Graduate School of Pure and Applied Science; Volkholz, J. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik

    2007-06-15

    We study U(1) gauge theory on a 4d non-commutative torus, where two directions are non-commutative. Monte Carlo simulations are performed after mapping the regularized theory onto a U(N) lattice gauge theory in d=2. At intermediate coupling strength, we find a phase in which open Wilson lines acquire non-zero vacuum expectation values, which implies the spontaneous breakdown of translational invariance. In this phase, various physical quantities obey clear scaling behaviors in the continuum limit with a fixed non- commutativity parameter {theta}, which provides evidence for a possible continuum theory. In the weak coupling symmetric phase, the dispersion relation involves a negative IR-singular term, which is responsible for the observed phase transition. (orig.)

  3. Simulation Results for U(1) Gauge Theory on Non-Commutative Spaces

    CERN Document Server

    Bietenholz, W; Nishimura, J; Susaki, Y; Torrielli, A; Volkholz, J

    2007-01-01

    We present numerical results for U(1) gauge theory in 2d and 4d spaces involving a non-commutative plane. Simulations are feasible thanks to a mapping of the non-commutative plane onto a twisted matrix model. In d=2 it was a long-standing issue if Wilson loops are (partially) invariant under area-preserving diffeomorphisms. We show that non-perturbatively this invariance breaks, including the subgroup SL(2,R). In both cases, d=2 and d=4, we extrapolate our results to the continuum and infinite volume by means of a Double Scaling Limit. In d=4 this limit leads to a phase with broken translation symmetry, which is not affected by the perturbatively known IR instability. Therefore the photon may survive in a non-commutative world.

  4. Relativistic Spectrum of Hydrogen Atom in Space-Time Non-Commutativity

    CERN Document Server

    Moumni, Mustafa; Zaim, Slimane; 10.1063/1.4715429

    2012-01-01

    We study space-time non-commutativity applied to the hydrogen atom via the Seiberg-Witten map and its phenomenological effects. We find that it modifies the Coulomb potential in the Hamiltonian and add an r-3 part. By calculating the energies from Dirac equation using perturbation theory, we study the modifications to the hydrogen spectrum. We find that it removes the degeneracy with respect to the total angular momentum quantum number and acts like a Lamb shift. Comparing the results with experimental values from spectroscopy, we get a new bound for the space-time non-commutative parameter. N.B: In precedent works (arXiv:0907.1904, arXiv:1003.5732 and arXiv:1006.4590), we have used the Bopp Shift formulation of non-commutativity but here use it \\`a la Seiberg-Witten in the Relativistic case.

  5. Additional degrees of freedom associated with position measurements in non-commutative quantum mechanics

    CERN Document Server

    Rohwer, CM

    2012-01-01

    In this thesis we shall demonstrate that a measurement of position alone in non-commutative space cannot yield complete information about the quantum state of a particle. Indeed, the formalism used entails a description that is non-local in that it requires all orders of positional derivatives through the star product that is used ubiquitously to map operator multiplication onto function multiplication in non-commutative systems. It will be shown that there exist several equivalent local descriptions, which are arrived at via the introduction of additional degrees of freedom. Consequently non-commutative quantum mechanical position measurements necessarily confront us with some additional structure which is necessary to specify quantum states completely. The remainder of the thesis, will involve investigations into the physical interpretation of these additional degrees of freedom. For one particular local formulation, the corresponding classical theory will be used to demonstrate that the concept of extended...

  6. Mapping seagrass coverage and spatial patterns with high spatial resolution IKONOS imagery

    Science.gov (United States)

    Pu, Ruiliang; Bell, Susan

    2017-02-01

    Seagrass habitats in subtidal coastal waters provide a variety of ecosystem functions and services and there is an increasing need to acquire information on spatial and temporal dynamics of this resource. Here, we explored the capability of IKONOS (IKO) data of high resolution (4 m) for mapping seagrass cover [submerged aquatic vegetation (%SAV) cover] along the mid-western coast of Florida, USA. We also compared seagrass maps produced with IKO data with that obtained using the Landsat TM sensor with lower resolution (30 m). Both IKO and TM data, collected in October 2009, were preprocessed to calculate water depth invariant bands to normalize the effect of varying depth on bottom spectra recorded by the two satellite sensors and further the textural information was extracted from IKO data. Our results demonstrate that the high resolution IKO sensor produced a higher accuracy than the TM sensor in a three-class % SAV cover classification. Of note is that the OA of %SAV cover mapping at our study area created with IKO data was 5-20% higher than that from other studies published. We also examined the spatial distribution of seagrass over a spatial range of 4-240 m using the Ripley's K function [L(d)] and IKO data that represented four different grain sizes [4 m (one IKO pixel), 8 m (2 × 2 IKO pixels), 12 m (3 × 3 IKO pixels), and 16 m (4 × 4 IKO pixels)] from moderate-dense seagrass cover along a set of six transects. The Ripley's K metric repeatedly indicated that seagrass cover representing 4 m × 4 m pixels displayed a dispersed (or slightly dispersed) pattern over distances of pattern of cover over 9-240 m. The spatial pattern of seagrass cover created with the three additional grain sizes (i.e., 2 × 24 m IKO pixels, 3 × 34 m IKO pixels, and 4 × 4 m IKO pixels) show a dispersed (or slightly dispersed) pattern across 4-32 m and a random or slightly clustered pattern across 33-240 m. Given the first report on using satellite observations to quantify seagrass

  7. Subclinical keratoconus detection by pattern analysis of corneal and epithelial thickness maps with optical coherence tomography.

    Science.gov (United States)

    Li, Yan; Chamberlain, Winston; Tan, Ou; Brass, Robert; Weiss, Jack L; Huang, David

    2016-02-01

    To screen for subclinical keratoconus by analyzing corneal, epithelial, and stromal thickness map patterns with Fourier-domain optical coherence tomography (OCT). Four centers in the United States. Cross-sectional observational study. Eyes of normal subjects, subclinical keratoconus eyes, and the topographically normal eye of a unilateral keratoconus patient were studied. Corneas were scanned using a 26,000 Hz Fourier-domain OCT system (RTVue). Normal subjects were divided into training and evaluation groups. Corneal, epithelial, and stromal thickness maps and derived diagnostic indices, including pattern standard deviation (PSD) variables and pachymetric map-based keratoconus risk scores, were calculated from the OCT data. Area under the receiver operating characteristic curve (AUC) analysis was used to evaluate the diagnostic accuracy of the indices. The study comprised 150 eyes of 83 normal subjects, 50 subclinical keratoconus eyes of 32 patients, and 1 topographically normal eye of a unilateral keratoconus patient. Subclinical keratoconus was characterized by inferotemporal thinning of the cornea, epithelium, and stroma. The PSD values for corneal (P keratoconus risk score (AUC = 0.735). High-resolution Fourier-domain OCT could map corneal, epithelial, and stromal thicknesses. Corneal and sublayer thickness changes in subclinical keratoconus could be detected with high accuracy using PSD variables. These new diagnostic variables might be useful in the detection of early keratoconus. Oregon Health and Science University (OHSU) and Drs. Li, Tan, and Huang have a significant financial interest in Optovue, Inc. These potential conflicts have been reviewed and managed by OHSU. Dr. Brass receives research grants from Optovue, Inc. Drs. Chamberlain and Weiss have no financial or proprietary interest in any material or method mentioned. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  8. Non-commutative field theory and the parameters of Lorentz violation in QED

    Directory of Open Access Journals (Sweden)

    S Aghababaei

    2011-09-01

    Full Text Available Non-commutative field theory as a theory including the Lorentz violation can be constructed in two different ways. In the first method, the non-commutative fields are the same as the ordinary ones while the gauge group is restricted to U(n. For example, the symmetry group of standard model in non-commutative space is U(3×(2×U(1 which can be reduced to SU(3×SU(2×U(1 by two appropriate spontaneous symmetry breaking. In contrast, in the second method, the non-commutative gauge theory can be constructed for SU(n gauge group via Seiberg- Witten map. In this work, we want to find the relation between the NC-parameter and the Lorentz violation parameters for the first method and compare our results with what is already found in the second one. At the end, we obtain new limits on non-commutative parameter by using the existing bounds on the Lorentz Violation parameters.

  9. The mortality rates and the space-time patterns of John Snow's cholera epidemic map.

    Science.gov (United States)

    Shiode, Narushige; Shiode, Shino; Rod-Thatcher, Elodie; Rana, Sanjay; Vinten-Johansen, Peter

    2015-06-17

    Snow's work on the Broad Street map is widely known as a pioneering example of spatial epidemiology. It lacks, however, two significant attributes required in contemporary analyses of disease incidence: population at risk and the progression of the epidemic over time. Despite this has been repeatedly suggested in the literature, no systematic investigation of these two aspects was previously carried out. Using a series of historical documents, this study constructs own data to revisit Snow's study to examine the mortality rate at each street location and the space-time pattern of the cholera outbreak. This study brings together records from a series of historical documents, and prepares own data on the estimated number of residents at each house location as well as the space-time data of the victims, and these are processed in GIS to facilitate the spatial-temporal analysis. Mortality rates and the space-time pattern in the victims' records are explored using Kernel Density Estimation and network-based Scan Statistic, a recently developed method that detects significant concentrations of records such as the date and place of victims with respect to their distance from others along the street network. The results are visualised in a map form using a GIS platform. Data on mortality rates and space-time distribution of the victims were collected from various sources and were successfully merged and digitised, thus allowing the production of new map outputs and new interpretation of the 1854 cholera outbreak in London, covering more cases than Snow's original report and also adding new insights into their space-time distribution. They confirmed that areas in the immediate vicinity of the Broad Street pump indeed suffered from excessively high mortality rates, which has been suspected for the past 160 years but remained unconfirmed. No distinctive pattern was found in the space-time distribution of victims' locations. The high mortality rates identified around the

  10. Genetic landscapes GIS Toolbox: tools to map patterns of genetic divergence and diversity.

    Science.gov (United States)

    Vandergast, Amy G.; Perry, William M.; Lugo, Roberto V.; Hathaway, Stacie A.

    2011-01-01

    The Landscape Genetics GIS Toolbox contains tools that run in the Geographic Information System software, ArcGIS, to map genetic landscapes and to summarize multiple genetic landscapes as average and variance surfaces. These tools can be used to visualize the distribution of genetic diversity across geographic space and to study associations between patterns of genetic diversity and geographic features or other geo-referenced environmental data sets. Together, these tools create genetic landscape surfaces directly from tables containing genetic distance or diversity data and sample location coordinates, greatly reducing the complexity of building and analyzing these raster surfaces in a Geographic Information System.

  11. Underlying mechanisms for commuting and migration processes

    Science.gov (United States)

    Simini, Filippo; Barabasi, Albert-Laszlo; Bagrow, James

    2012-02-01

    Both frequent commuting and long-term migration are complex human processes that strongly depend on socio-demographic, spatial, political, and even economic factors. We can describe both processes using weighted networks, in which nodes represent geographic locations and link weights denote the flux of individuals who commute (or migrate) between locations. Although both processes concern the movements of individuals, they are very different: commuting takes place on a daily (or weekly) basis and always between the same two locations, while migration is a rare, one-way displacement. Despite these differences, a recently proposed stochastic model, the Radiation model, provides evidence that both processes may be successfully described by the same underlying mechanism. For example, quantities of interest for either process, such as the distributions of trip length and destination populations, appear remarkably similar to the model's predictions. We explore the similarities and differences between commuting and migration both empirically, using census data for the United States, and theoretically, by comparing these commuting and migration networks to the predictions given by the Radiation model.

  12. The knee pain map: reliability of a method to identify knee pain location and pattern.

    Science.gov (United States)

    Thompson, Laura R; Boudreau, Robert; Hannon, Michael J; Newman, Anne B; Chu, Constance R; Jansen, Mary; Nevitt, Michael C; Kwoh, C Kent

    2009-06-15

    To describe the location and pattern of knee pain in patients with chronic, frequent knee pain using the Knee Pain Map, and to evaluate the inter- and intrarater reliability of the map. A cohort of 799 participants from the University of Pittsburgh Osteoarthritis Initiative Clinical Center who had knee pain in the last 12 months were studied. Trained interviewers assessed and recorded participant-reported knee pain patterns into 8 local areas, 4 regional areas, or as diffuse. Inter- and intrarater reliability were assessed using Fleiss' kappa. Participants most often reported localized (69%) followed by regional (14%) or diffuse (10%) knee pain. In those with localized pain, the most commonly reported locations were the medial (56%) and lateral (43%) joint lines. In those with regional pain, the most commonly reported regions were the patella (44%) and medial region (38%). There was excellent interrater reliability for the identification of localized and regional pain patterns (kappa = 0.7-0.9 and 0.7-0.8, respectively). The interrater reliability for specific locations was also excellent (kappa = 0.7-1.0) when the number of participants with pain in a location was >4. For regional pain, the kappa for specific regions varied from 0.7-1.0. The majority of participants could identify the location of their knee pain, and trained interviewers could reliably record those locations. The variation in locations suggests that there are multiple sources of pain in knee OA. Additional studies are needed to determine whether specific knee pain patterns correlate with discrete pathologic findings on radiographs or magnetic resonance images.

  13. Mapping field-scale spatial patterns of size and activity of the denitrifier community.

    Science.gov (United States)

    Philippot, Laurent; Cuhel, Jiri; Saby, Nicolas P A; Chèneby, Dominique; Chronáková, Alicia; Bru, David; Arrouays, Dominique; Martin-Laurent, Fabrice; Simek, Miloslav

    2009-06-01

    There is ample evidence that microbial processes can exhibit large variations in activity on a field scale. However, very little is known about the spatial distribution of the microbial communities mediating these processes. Here we used geostatistical modelling to explore spatial patterns of size and activity of the denitrifying community, a functional guild involved in N-cycling, in a grassland field subjected to different cattle grazing regimes. We observed a non-random distribution pattern of the size of the denitrifier community estimated by quantification of the denitrification genes copy numbers with a macro-scale spatial dependence (6-16 m) and mapped the distribution of this functional guild in the field. The spatial patterns of soil properties, which were strongly affected by presence of cattle, imposed significant control on potential denitrification activity, potential N(2)O production and relative abundance of some denitrification genes but not on the size of the denitrifier community. Absolute abundance of most denitrification genes was not correlated with the distribution patterns of potential denitrification activity or potential N(2)O production. However, the relative abundance of bacteria possessing the nosZ gene encoding the N(2)O reductase in the total bacterial community was a strong predictor of the N(2)O/(N(2) + N(2)O) ratio, which provides evidence for a relationship between bacterial community composition based on the relative abundance of denitrifiers in the total bacterial community and ecosystem processes. More generally, the presented geostatistical approach allows integrated mapping of microbial communities, and hence can facilitate our understanding of relationships between the ecology of microbial communities and microbial processes along environmental gradients.

  14. Dynamical prediction and pattern mapping in short-term load forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, Luis Antonio; Rodrigues, Daniela D.; Lima, Silvio T. [Departamento de Engenharia Eletronica, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, 31270-901 Belo Horizonte, MG (Brazil); Martinez, Carlos Barreira [Departamento de Engenharia Hidraulica e Recursos Hidricos, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, 31270-901 Belo Horizonte, MG (Brazil)

    2008-01-15

    This work will not put forward yet another scheme for short-term load forecasting but rather will provide evidences that may improve our understanding about fundamental issues which underlay load forecasting problems. In particular, load forecasting will be decomposed into two main problems, namely dynamical prediction and pattern mapping. It is argued that whereas the latter is essentially static and becomes nonlinear when weekly features in the data are taken into account, the former might not be deterministic at all. In such cases there is no determinism (serial correlations) in the data apart from the average cycle and the best a model can do is to perform pattern mapping. Moreover, when there is determinism in addition to the average cycle, the underlying dynamics are sometimes linear, in which case there is no need to resort to nonlinear models to perform dynamical prediction. Such conclusions were confirmed using real load data and surrogate data analysis. In a sense, the paper details and organizes some general beliefs found in the literature on load forecasting. This sheds some light on real model-building and forecasting problems and helps understand some apparently conflicting results reported in the literature. (author)

  15. A multi-modal face recognition method using complete local derivative patterns and depth maps.

    Science.gov (United States)

    Yin, Shouyi; Dai, Xu; Ouyang, Peng; Liu, Leibo; Wei, Shaojun

    2014-10-20

    In this paper, we propose a multi-modal 2D + 3D face recognition method for a smart city application based on a Wireless Sensor Network (WSN) and various kinds of sensors. Depth maps are exploited for the 3D face representation. As for feature extraction, we propose a new feature called Complete Local Derivative Pattern (CLDP). It adopts the idea of layering and has four layers. In the whole system, we apply CLDP separately on Gabor features extracted from a 2D image and depth map. Then, we obtain two features: CLDP-Gabor and CLDP-Depth. The two features weighted by the corresponding coefficients are combined together in the decision level to compute the total classification distance. At last, the probe face is assigned the identity with the smallest classification distance. Extensive experiments are conducted on three different databases. The results demonstrate the robustness and superiority of the new approach. The experimental results also prove that the proposed multi-modal 2D + 3D method is superior to other multi-modal ones and CLDP performs better than other Local Binary Pattern (LBP) based features.

  16. A Multi-Modal Face Recognition Method Using Complete Local Derivative Patterns and Depth Maps

    Directory of Open Access Journals (Sweden)

    Shouyi Yin

    2014-10-01

    Full Text Available In this paper, we propose a multi-modal 2D + 3D face recognition method for a smart city application based on a Wireless Sensor Network (WSN and various kinds of sensors. Depth maps are exploited for the 3D face representation. As for feature extraction, we propose a new feature called Complete Local Derivative Pattern (CLDP. It adopts the idea of layering and has four layers. In the whole system, we apply CLDP separately on Gabor features extracted from a 2D image and depth map. Then, we obtain two features: CLDP-Gabor and CLDP-Depth. The two features weighted by the corresponding coefficients are combined together in the decision level to compute the total classification distance. At last, the probe face is assigned the identity with the smallest classification distance. Extensive experiments are conducted on three different databases. The results demonstrate the robustness and superiority of the new approach. The experimental results also prove that the proposed multi-modal 2D + 3D method is superior to other multi-modal ones and CLDP performs better than other Local Binary Pattern (LBP based features.

  17. T2 mapping of CT remodelling patterns in interstitial lung disease

    Energy Technology Data Exchange (ETDEWEB)

    Buzan, Maria T.A. [Iuliu Hatieganu University of Medicine and Pharmacy, Department of Pneumology, Cluj-Napoca (Romania); Thoraxklinik at Heidelberg University Hospital, Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Heidelberg (Germany); University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); Eichinger, Monika; Heussel, Claus Peter [Thoraxklinik at Heidelberg University Hospital, Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Heidelberg (Germany); Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), Heidelberg (Germany); Kreuter, Michael; Herth, Felix J. [Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), Heidelberg (Germany); Thoraxklinik at Heidelberg University Hospital, Department of Pneumology, Center for Rare and Interstitial Lung Diseases, Heidelberg (Germany); Kauczor, Hans-Ulrich [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology, Heidelberg (Germany); Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), Heidelberg (Germany); Warth, Arne [Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), Heidelberg (Germany); University Hospital Heidelberg, Institute for Pathology, Heidelberg (Germany); Pop, Carmen Monica [Iuliu Hatieganu University of Medicine and Pharmacy, Department of Pneumology, Cluj-Napoca (Romania); Dinkel, Julien [Thoraxklinik at Heidelberg University Hospital, Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Heidelberg (Germany); Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), Heidelberg (Germany); Comprehensive Pneumology Center Munich (CPC-M), German Center for Lung Research (DZL), Munich (Germany); Ludwig-Maximilians-University Hospital Munich, Institute for Clinical Radiology, Munich (Germany)

    2015-11-15

    To evaluate lung T2 mapping for quantitative characterization and differentiation of ground-glass opacity (GGO), reticulation (RE) and honeycombing (HC) in usual interstitial pneumonia (UIP) and non-specific interstitial pneumonia (NSIP). Twelve patients with stable UIP or NSIP underwent thin-section multislice CT and 1.5-T MRI of the lung. A total of 188 regions were classified at CT into normal (n = 29) and pathological areas, including GGO (n = 48), RE (n = 60) and HC (n = 51) predominant lesions. Entire lung T2 maps based on multi-echo single shot TSE sequence (TE: 20, 40, 79, 140, 179 ms) were generated from each subject with breath-holds at end-expiration and ECG-triggering. The median T2 relaxation of GGO was 67 ms (range 60-72 ms). RE predominant lesions had a median relaxation of 74 ms (range 69-79 ms), while for HC pattern this was 79 ms (range 74-89 ms). The median T2 relaxation for normal lung areas was 41 ms (ranged 38-49 ms), and showed significant difference to pathological areas (p < 0.001). A statistical difference was found between the T2 relaxation of GGO, RE and HC (p < 0.05). The proposed method provides quantitative information for pattern differentiation, potentially allowing for monitoring of progression and response to treatment, in interstitial lung disease. (orig.)

  18. Technology's Role in Learning at a Commuter Campus: The Student Perspective

    Science.gov (United States)

    Buckenmeyer, Janet A.; Barczyk, Casimir; Hixon, Emily; Zamojski, Heather; Tomory, Annette

    2016-01-01

    Patterns of technology ownership and usage, as well as skills with and preferences for various technologies, affect the college experience (Educause 2012). Students at a commuter campus of a large Midwestern public university were surveyed about technology and the learning process: 94% of the respondents believed that technology had the potential…

  19. Commutative algebra constructive methods finite projective modules

    CERN Document Server

    Lombardi, Henri

    2015-01-01

    Translated from the popular French edition, this book offers a detailed introduction to various basic concepts, methods, principles, and results of commutative algebra. It takes a constructive viewpoint in commutative algebra and studies algorithmic approaches alongside several abstract classical theories. Indeed, it revisits these traditional topics with a new and simplifying manner, making the subject both accessible and innovative. The algorithmic aspects of such naturally abstract topics as Galois theory, Dedekind rings, Prüfer rings, finitely generated projective modules, dimension theory of commutative rings, and others in the current treatise, are all analysed in the spirit of the great developers of constructive algebra in the nineteenth century. This updated and revised edition contains over 350 well-arranged exercises, together with their helpful hints for solution. A basic knowledge of linear algebra, group theory, elementary number theory as well as the fundamentals of ring and module theory is r...

  20. Outer commutator words are uniformly concise

    CERN Document Server

    Fernández-Alcober, Gustavo A

    2009-01-01

    We prove that outer commutator words are uniformly concise, i.e. if an outer commutator word w takes m different values in a group G, then the order of the verbal subgroup w(G) is bounded by a function depending only on m and not on w or G. This is obtained as a consequence of a structure theorem for the subgroup w(G), which is valid if G is soluble, and without assuming that w takes finitely many values in G. More precisely, there is an abelian series of w(G), such that every section of the series can be generated by values of w all of whose powers are also values of w in that section. For the proof of this latter result, we introduce a new representation of outer commutator words by means of binary trees, and we use the structure of the trees to set up an appropriate induction.

  1. Survey of how staff commute to work

    CERN Multimedia

    2014-01-01

    A survey was initiated by the Canton of Geneva (Direction Générale des Transports) and the Swiss Permanent Mission to the United Nations, and is aimed at better understanding how staff in International Organisations commute to/from work so as to better plan future works (road access, public transport, etc.). The ILO, WHO, UNAIDs, Global Fund, IFRC, CERN and UNOG are taking part in this important survey.   People living in Switzerland or France are invited to respond to this survey. The purpose of this survey is to better understand: - your commuting habits, - your willingness to explore alternative commuting options, - your expectations and needs. All data provided to this external company (www.mobilidee.ch) will be kept confidential and will only be used for this particular study. CERN has received all guarantees of confidentiality from this company. Many thanks for your collaboration! GS Department

  2. Commutability of food microbiology proficiency testing samples.

    Science.gov (United States)

    Abdelmassih, M; Polet, M; Goffaux, M-J; Planchon, V; Dierick, K; Mahillon, J

    2014-03-01

    Food microbiology proficiency testing (PT) is a useful tool to assess the analytical performances among laboratories. PT items should be close to routine samples to accurately evaluate the acceptability of the methods. However, most PT providers distribute exclusively artificial samples such as reference materials or irradiated foods. This raises the issue of the suitability of these samples because the equivalence-or 'commutability'-between results obtained on artificial vs. authentic food samples has not been demonstrated. In the clinical field, the use of noncommutable PT samples has led to erroneous evaluation of the performances when different analytical methods were used. This study aimed to provide a first assessment of the commutability of samples distributed in food microbiology PT. REQUASUD and IPH organized 13 food microbiology PTs including 10-28 participants. Three types of PT items were used: genuine food samples, sterile food samples and reference materials. The commutability of the artificial samples (reference material or sterile samples) was assessed by plotting the distribution of the results on natural and artificial PT samples. This comparison highlighted matrix-correlated issues when nonfood matrices, such as reference materials, were used. Artificially inoculated food samples, on the other hand, raised only isolated commutability issues. In the organization of a PT-scheme, authentic or artificially inoculated food samples are necessary to accurately evaluate the analytical performances. Reference materials, used as PT items because of their convenience, may present commutability issues leading to inaccurate penalizing conclusions for methods that would have provided accurate results on food samples. For the first time, the commutability of food microbiology PT samples was investigated. The nature of the samples provided by the organizer turned out to be an important factor because matrix effects can impact on the analytical results. © 2013

  3. Mapping patterns of long-term settlement in Northern Mesopotamia at a large scale.

    Science.gov (United States)

    Menze, Bjoern H; Ur, Jason A

    2012-04-03

    The landscapes of the Near East show both the first settlements and the longest trajectories of settlement systems. Mounding is a characteristic property of these settlement sites, resulting from millennia of continuing settlement activity at distinguished places. So far, however, this defining feature of ancient settlements has not received much attention, or even been the subject of systematic evaluation. We propose a remote sensing approach for comprehensively mapping the pattern of human settlement at large scale and establish the largest archaeological record for a landscape in Mesopotamia, mapping about 14,000 settlement sites--spanning eight millennia--at 15-m resolution in a 23,000-km(2) area in northeastern Syria. To map both low- and high-mounded places--the latter of which are often referred to as "tells"--we develop a strategy for detecting anthrosols in time series of multispectral satellite images and measure the volume of settlement sites in a digital elevation model. Using this volume as a proxy to continued occupation, we find a dependency of the long-term attractiveness of a site on local water availability, but also a strong relation to the relevance within a basin-wide exchange network that we can infer from our record and third millennium B.C. intersite routes visible on the ground until recent times. We believe it is possible to establish a nearly comprehensive map of human settlements in the fluvial plains of northern Mesopotamia and beyond, and site volume may be a key quantity to uncover long-term trends in human settlement activity from such a record.

  4. PNAS Plus: Mapping patterns of long-term settlement in Northern Mesopotamia at a large scale

    Science.gov (United States)

    Menze, Bjoern H.; Ur, Jason A.

    2012-04-01

    The landscapes of the Near East show both the first settlements and the longest trajectories of settlement systems. Mounding is a characteristic property of these settlement sites, resulting from millennia of continuing settlement activity at distinguished places. So far, however, this defining feature of ancient settlements has not received much attention, or even been the subject of systematic evaluation. We propose a remote sensing approach for comprehensively mapping the pattern of human settlement at large scale and establish the largest archaeological record for a landscape in Mesopotamia, mapping about 14,000 settlement sites-spanning eight millennia-at 15-m resolution in a 23,000-km2 area in northeastern Syria. To map both low- and high-mounded places-the latter of which are often referred to as "tells"-we develop a strategy for detecting anthrosols in time series of multispectral satellite images and measure the volume of settlement sites in a digital elevation model. Using this volume as a proxy to continued occupation, we find a dependency of the long-term attractiveness of a site on local water availability, but also a strong relation to the relevance within a basin-wide exchange network that we can infer from our record and third millennium B.C. intersite routes visible on the ground until recent times. We believe it is possible to establish a nearly comprehensive map of human settlements in the fluvial plains of northern Mesopotamia and beyond, and site volume may be a key quantity to uncover long-term trends in human settlement activity from such a record.

  5. Network-level accident-mapping: Distance based pattern matching using artificial neural network.

    Science.gov (United States)

    Deka, Lipika; Quddus, Mohammed

    2014-04-01

    The objective of an accident-mapping algorithm is to snap traffic accidents onto the correct road segments. Assigning accidents onto the correct segments facilitate to robustly carry out some key analyses in accident research including the identification of accident hot-spots, network-level risk mapping and segment-level accident risk modelling. Existing risk mapping algorithms have some severe limitations: (i) they are not easily 'transferable' as the algorithms are specific to given accident datasets; (ii) they do not perform well in all road-network environments such as in areas of dense road network; and (iii) the methods used do not perform well in addressing inaccuracies inherent in and type of road environment. The purpose of this paper is to develop a new accident mapping algorithm based on the common variables observed in most accident databases (e.g. road name and type, direction of vehicle movement before the accident and recorded accident location). The challenges here are to: (i) develop a method that takes into account uncertainties inherent to the recorded traffic accident data and the underlying digital road network data, (ii) accurately determine the type and proportion of inaccuracies, and (iii) develop a robust algorithm that can be adapted for any accident set and road network of varying complexity. In order to overcome these challenges, a distance based pattern-matching approach is used to identify the correct road segment. This is based on vectors containing feature values that are common in the accident data and the network data. Since each feature does not contribute equally towards the identification of the correct road segments, an ANN approach using the single-layer perceptron is used to assist in "learning" the relative importance of each feature in the distance calculation and hence the correct link identification. The performance of the developed algorithm was evaluated based on a reference accident dataset from the UK confirming that

  6. Two Approaches to Non-Commutative Geometry

    CERN Document Server

    Kisil, V V

    1997-01-01

    Looking to the history of mathematics one could find out two outer approaches to Geometry. First one (algebraic) is due to Descartes and second one (group-theoretic)--to Klein. We will see that they are not rivalling but are tied (by Galois). We also examine their modern life as philosophies of non-commutative geometry. Connections between different objects (see keywords) are discussed. Keywords: Heisenberg group, Weyl commutation relation, Manin plain, quantum groups, SL(2, R), Hardy space, Bergman space, Segal-Bargmann space, Szeg"o projection, Bergman projection, Clifford analysis, Moebius transformations, functional calculus, Weyl calculus (quantization), Berezin quantization, Wick ordering, quantum mechanics.

  7. Congestion Behavior under Uncertainty on Morning Commute with Preferred Arrival Time Interval

    Directory of Open Access Journals (Sweden)

    LingLing Xiao

    2014-01-01

    Full Text Available This paper extends the bottleneck model to study congestion behavior of morning commute with flexible work schedule. The proposed model assumes a stochastic bottleneck capacity which follows a uniform distribution and homogeneous commuters who have the same preferred arrival time interval. The commuters are fully aware of the stochastic properties of travel time and schedule delay distributions at all departure times that emerge from day-to-day capacity variations. The commuters’ departure time choice follows user equilibrium (UE principle in terms of the expected trip cost. Analytical and numerical solutions of this model are provided. The equilibrium departure time patterns are examined which show that the stochastic capacity increases the mean trip cost and lengthens the rush hour. The adoption of flexitime results in less congestion and more efficient use of bottleneck capacity than fixed-time work schedule. The longer the flexi-time interval is, the more uniformly distributed the departure times are.

  8. Discrete Symmetries In Lorentz-Invariant Non-Commutative QED

    CERN Document Server

    Morita, K

    2003-01-01

    It is pointed out that the usual $\\theta$-algebra assumed for non-commuting coordinates is not $P$- and $T$-invariant, unless one {\\it formally} transforms the non-commutativity parameter $\\theta^{\\mu\

  9. Real structures on almost-commutative spectral triples

    CERN Document Server

    Ćaćić, Branimir

    2012-01-01

    We refine the reconstruction theorem for almost-commutative spectral triples to a result for real almost-commutative spectral triples, clarifying, in the process, both concrete and abstract definitions of real commutative and almost-commutative spectral triples. In particular, we find that a real almost-commutative spectral triple algebraically encodes the commutative *-algebra of the base manifold in a canonical way, and that a compact oriented Riemannian manifold admits real (almost-)commutative spectral triples of arbitrary KO-dimension. Moreover, we define a notion of smooth family of real finite spectral triples and of the twisting of a concrete real commutative spectral triple by such a family, with interesting KK-theoretic and gauge-theoretic implications.

  10. Spatial pattern of soil and soybean crop: an assessment using digital mapping techniques

    Science.gov (United States)

    Castro Franco, Mauricio; Cordoba, Mariano; Costa, Jose Luis; Aparicio, Virginia; Domenech, Marisa

    2017-04-01

    The aim of this study was to analyze the relationships among spatial patterns of soil properties and soybean crop. The study was carried out in three provinces of Argentina: (i) Buenos Aires (BA), (ii) Entre Rios (ER) and (iii) Cordoba (COR). In each province, 2 agricultural fields were selected. Ancillary information related to soil forming factors in each field was gathered, for example apparent electrical conductivity (ECa), NDVI and yield maps. We used principal component spatial analysis (MULTISPATI-PCA) to delimit zones for soil type by field. To zonal validation, 4 sampling sites were located in which we collected soil samples, grain yield and soybean crop quality. Random Forest (RF) was used to determine the importance of soil properties over soybean crop properties. For comparing soil properties in each zone between fields, a mix lineal model and ANOVA were adjusted. Our results suggest that MULTISPATI-PCA was efficient to delimit zones for soil type. Relationships between soil properties and crop yield were examined and understood. However, it did not occur with crop quality patterns. Topography did not prove to be an accurate indicator of spatial pattern relations of soil properties and crop, whereas ECa, yield maps and NDVI proved to be effective indicators. Grains m-2 and NDVI were affected homogeneously and were showed spatial correspondence according to soil limitations. Percentage of protein did not show spatial correspondence with delimitated zones in saline soils, particularly in ER. In such fields, Om and pH were important for percentage of protein. It was evidenced that a direct relation exists between complex relationship of soil and crop properties and soil degradation.

  11. Unsupervised pattern recognition in continuous seismic wavefield records using Self-Organizing Maps

    Science.gov (United States)

    Köhler, Andreas; Ohrnberger, Matthias; Scherbaum, Frank

    2010-09-01

    Modern acquisition of seismic data on receiver networks worldwide produces an increasing amount of continuous wavefield recordings. In addition to manual data inspection, seismogram interpretation requires therefore new processing utilities for event detection, signal classification and data visualization. The use of machine learning techniques automatises decision processes and reveals the statistical properties of data. This approach is becoming more and more important and valuable for large and complex seismic records. Unsupervised learning allows the recognition of wavefield patterns, such as short-term transients and long-term variations, with a minimum of domain knowledge. This study applies an unsupervised pattern recognition approach for the discovery, imaging and interpretation of temporal patterns in seismic array recordings. For this purpose, the data is parameterized by feature vectors, which combine different real-valued wavefield attributes for short time windows. Standard seismic analysis tools are used as feature generation methods, such as frequency-wavenumber, polarization and spectral analysis. We use Self-Organizing Maps (SOMs) for a data-driven feature selection, visualization and clustering procedure. The application to continuous recordings of seismic signals from an active volcano (Mount Merapi, Java, Indonesia) shows that volcano-tectonic and rockfall events can be detected and distinguished by clustering the feature vectors. Similar results are obtained in terms of correctly classifying events compared to a previously implemented supervised classification system. Furthermore, patterns in the background wavefield, that is the 24-hr cycle due to human activity, are intuitively visualized by means of the SOM representation. Finally, we apply our technique to an ambient seismic vibration record, which has been acquired for local site characterization. Disturbing wavefield patterns are identified which affect the quality of Love wave dispersion

  12. Interpreting Patterns of Gene Expression with Self-Organizing Maps: Methods and Application to Hematopoietic Differentiation

    Science.gov (United States)

    Tamayo, Pablo; Slonim, Donna; Mesirov, Jill; Zhu, Qing; Kitareewan, Sutisak; Dmitrovsky, Ethan; Lander, Eric S.; Golub, Todd R.

    1999-03-01

    Array technologies have made it straightforward to monitor simultaneously the expression pattern of thousands of genes. The challenge now is to interpret such massive data sets. The first step is to extract the fundamental patterns of gene expression inherent in the data. This paper describes the application of self-organizing maps, a type of mathematical cluster analysis that is particularly well suited for recognizing and classifying features in complex, multidimensional data. The method has been implemented in a publicly available computer package, GENECLUSTER, that performs the analytical calculations and provides easy data visualization. To illustrate the value of such analysis, the approach is applied to hematopoietic differentiation in four well studied models (HL-60, U937, Jurkat, and NB4 cells). Expression patterns of some 6,000 human genes were assayed, and an online database was created. GENECLUSTER was used to organize the genes into biologically relevant clusters that suggest novel hypotheses about hematopoietic differentiation--for example, highlighting certain genes and pathways involved in "differentiation therapy" used in the treatment of acute promyelocytic leukemia.

  13. Commuter partnerships : balancing home, family, and distant work

    NARCIS (Netherlands)

    van der Klis, M.

    2009-01-01

    This study is about commuter partnerships. The commuter partnership is a particular non-standard household arrangement in which, for part of the time, one partner lives near his or her work and away from the communal family home, because the commuting distance is too great to travel on a daily basis

  14. Commuting Toeplitz and Hankel Operators on Harmonic Dirichlet Spaces

    Directory of Open Access Journals (Sweden)

    Qian Ding

    2017-01-01

    Full Text Available On the harmonic Dirichlet space of the unit disk, the commutativity of Toeplitz and Hankel operators is studied. We obtain characterizations of commuting Toeplitz and Hankel operators and essentially commuting (semicommuting Toeplitz and Hankel operators with general symbols.

  15. A Cohomology Theory for Commutative Monoids

    Directory of Open Access Journals (Sweden)

    María Calvo-Cervera

    2015-10-01

    Full Text Available Extending Eilenberg–Mac Lane’s cohomology of abelian groups, a cohomology theory is introduced for commutative monoids. The cohomology groups in this theory agree with the pre-existing ones by Grillet in low dimensions, but they differ beyond dimension two. A natural interpretation is given for the three-cohomology classes in terms of braided monoidal groupoids.

  16. Commutative monads as a theory of distributions

    DEFF Research Database (Denmark)

    Kock, Anders

    2012-01-01

    It is shown how the theory of commutative monads provides an axiomatic framework for several aspects of distribution theory in a broad sense, including probability distributions, physical extensive quantities, and Schwartz distributions of compact support. Among the particular aspects considered...... here are the notions of convolution, density, expectation, and conditional probability....

  17. Non-commutative multi-dimensional cosmology

    CERN Document Server

    Khosravi, N; Sepangi, H R

    2006-01-01

    A non-commutative multi-dimensional cosmological model is introduced and used to address the issues of compactification and stabilization of extra dimensions and the cosmological constant problem. We show that in such a scenario these problems find natural solutions in a universe described by an increasing time parameter.

  18. Commutative monads as a theory of distributions

    DEFF Research Database (Denmark)

    Kock, Anders

    2012-01-01

    It is shown how the theory of commutative monads provides an axiomatic framework for several aspects of distribution theory in a broad sense, including probability distributions, physical extensive quantities, and Schwartz distributions of compact support. Among the particular aspects considered...... here are the notions of convolution, density, expectation, and conditional probability....

  19. Semigroups of Transformations Commuting with Idempotents

    Institute of Scientific and Technical Information of China (English)

    Janusz Konieczny

    2002-01-01

    For any idempotent ε in the semigroup PTn of partial transformations on a set with n elements, the structure in terms of Green's relations of the semigroup C(ε) of all transformations commuting with ε is determined, and the regular elements of C(ε) are characterized. Also, a criterion is given for C(ε) to be a regular semigroup.

  20. Redheffer representations and relaxed commutant lifting

    NARCIS (Netherlands)

    ter Horst, S.

    2011-01-01

    It is well known that the solutions of a (relaxed) commutant lifting problem can be described via a linear fractional representation of the Redheffer type. The coefficients of such Redheffer representations are analytic operator-valued functions defined on the unit disc D of the complex plane. In th

  1. Virtual Commuters? The American Transnational Academic Exchangee

    Directory of Open Access Journals (Sweden)

    Niehues, Wolfgang

    2006-01-01

    Full Text Available International student exchange in times of globalization faces numerous challenges. The Internet - making the world shrink to a global village - is often named one of them. How does the Internet affect the daily lives of American exchange students in Germany. Do they become virtual commuters?

  2. Chiral bosonization for non-commutative fields

    Energy Technology Data Exchange (ETDEWEB)

    Das, Ashok [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627-0171 (United States)]. E-mail: das@pas.rochester.edu; Gamboa, Jorge [Departamento de Fisica, Universidad de Santiago de Chile, Casilla 307, Santiago 2 (Chile); Mendez, Fernando [INFN, Laboratorio Nazionali del Gran Sasso, SS, 17bis, 67010 Asergi, L' Aquila (Italy); Lopez-Sarrion, Justo [Departamento de Fisica Teorica, Universidad de Zaragoza, Zaragoza 50009 (Spain)

    2004-05-01

    A model of chiral bosons on a non-commutative field space is constructed and new generalized bosonization (fermionization) rules for these fields are given. The conformal structure of the theory is characterized by a level of the Kac-Moody algebra equal to (1+{theta}{sup 2}) where {theta} is the non-commutativity parameter and chiral bosons living in a non-commutative fields space are described by a rational conformal field theory with the central charge of the Virasoro algebra equal to 1. The non-commutative chiral bosons are shown to correspond to a free fermion moving with a speed equal to c' = c(1+{theta}{sup 2}){sup 1/2} where c is the speed of light. Lorentz invariance remains intact if c is rescaled by c{yields}c'. The dispersion relation for bosons and fermions, in this case, is given by {omega} = c' vertical bar k vertical bar. (author)

  3. Statistical Parametric Mapping to Identify Differences between Consensus-Based Joint Patterns during Gait in Children with Cerebral Palsy

    Science.gov (United States)

    Papageorgiou, Eirini; Desloovere, Kaat; Molenaers, Guy; De Laet, Tinne

    2017-01-01

    Experts recently identified 49 joint motion patterns in children with cerebral palsy during a Delphi consensus study. Pattern definitions were therefore the result of subjective expert opinion. The present study aims to provide objective, quantitative data supporting the identification of these consensus-based patterns. To do so, statistical parametric mapping was used to compare the mean kinematic waveforms of 154 trials of typically developing children (n = 56) to the mean kinematic waveforms of 1719 trials of children with cerebral palsy (n = 356), which were classified following the classification rules of the Delphi study. Three hypotheses stated that: (a) joint motion patterns with ‘no or minor gait deviations’ (n = 11 patterns) do not differ significantly from the gait pattern of typically developing children; (b) all other pathological joint motion patterns (n = 38 patterns) differ from typically developing gait and the locations of difference within the gait cycle, highlighted by statistical parametric mapping, concur with the consensus-based classification rules. (c) all joint motion patterns at the level of each joint (n = 49 patterns) differ from each other during at least one phase of the gait cycle. Results showed that: (a) ten patterns with ‘no or minor gait deviations’ differed somewhat unexpectedly from typically developing gait, but these differences were generally small (≤3°); (b) all other joint motion patterns (n = 38) differed from typically developing gait and the significant locations within the gait cycle that were indicated by the statistical analyses, coincided well with the classification rules; (c) joint motion patterns at the level of each joint significantly differed from each other, apart from two sagittal plane pelvic patterns. In addition to these results, for several joints, statistical analyses indicated other significant areas during the gait cycle that were not included in the pattern definitions of the consensus

  4. Mapping spatial patterns of denitrifiers for bridging community ecology and microbial processes along environmental gradients

    Science.gov (United States)

    Bru, D.; Cuhel, J.; Saby, N.; Cheneby, D.; Chronokova, A.; Arrouays, D.; Martin-Laurent, F.; Simek, M.

    2010-12-01

    While there is ample evidence that microbial processes can exhibit large variations at a field scale, very little is known about the spatial distribution of the communities mediating these processes. To explore spatial patterns of size and activity of the denitrifying community, a functional guild involved in N-cycling, in a grassland field subjected to different cattle grazing regimes.We used geostatistical modeling to map the distribution of size and activity of the denitrifier community in the pasture. Size of the denitrifier community was estimated by PCR quantification of the denitrification gene copy numbers while its activity was estimated by measuring potential denitrification activity and potential N2O emissions. Non-random distribution patterns of the size and of the activity of the denitrifier community were observed with a field-scale spatial dependence. The soil properties, which were strongly affected by presence of cattle, imposed significant control on potential denitrification activity, potential N2O production but not on the size of the denitrifier community. The relative abundance of bacteria possessing the nosZ gene encoding the N2O reductase within the total bacterial community was a strong predictor of the N2O/N2 ratio. Our results clearly indicated that patterns of distribution of the abundance of denitrifiers can be modelled at a field scale. Characterization of such pattern at a field-scale constitutes the first step in modelling distribution of functional bacterial communities at a scale compatible with land management strategies. The absolute abundance of most denitrification genes was not correlated with potential denitrification activity or potential N2O production. However, the relative abundance of bacteria possessing the nosZ gene in the total bacterial community was a strong predictor of the N2O/(N2+N2O) ratio, suggesting a relationship between ecosystem processes and bacterial community composition.

  5. Intelligent Control of the Complex Technology Process Based on Adaptive Pattern Clustering and Feature Map

    Directory of Open Access Journals (Sweden)

    Wushan Cheng

    2008-01-01

    Full Text Available A kind of fuzzy neural networks (FNNs based on adaptive pattern clustering and feature map (APCFM is proposed to improve the property of the large delay and time varying of the sintering process. By using the density clustering and learning vector quantization (LVQ, the sintering process is divided automatically into subclasses which have similar clustering center and labeled fitting number. Then these labeled subclass samples are taken into fuzzy neural network (FNN to be trained; this network is used to solve the prediction problem of the burning through point (BTP. Using the 707 groups of actual training process data and the FNN to train APCFM algorithm, experiments prove that the system has stronger robustness and wide generality in clustering analysis and feature extraction.

  6. Mapping Citation Patterns of Book Chapters in the Book Citation Index

    CERN Document Server

    Torres-Salinas, Daniel; Robinson-Garcia, Nicolas; Fdez-Valdivia, J; García, J A; 10.1016/j.joi.2013.01.004

    2013-01-01

    In this paper we provide the reader with a visual representation of relationships among the impact of book chapters indexed in the Book Citation Index using information gain values and published by different academic publishers in specific disciplines. The impact of book chapters can be characterized statistically by citations histograms. For instance, we can compute the probability of occurrence of book chapters with a number of citations in different intervals for each academic publisher. We predict the similarity between two citation histograms based on the amount of relative information between such characterizations. We observe that the citation patterns of book chapters follow a Lotkaian distribution. This paper describes the structure of the Book Citation Index using 'heliocentric clockwise maps' which allow the reader not only to determine the grade of similarity of a given academic publisher indexed in the Book Citation Index with a specific discipline according to their citation distribution, but al...

  7. The physical environment and health-enhancing activity during the school commute: global positioning system, geographical information systems and accelerometry

    Directory of Open Access Journals (Sweden)

    David McMinn

    2014-05-01

    Full Text Available Active school travel is in decline. An understanding of the potential determinants of health-enhancing physical activity during the school commute may help to inform interventions aimed at reversing these trends. The purpose of this study was to identify the physical environmental factors associated with health-enhancing physical activity during the school commute. Data were collected in 2009 on 166 children commuting home from school in Scotland. Data on location and physical activity were measured using global positioning systems (GPS and accelerometers, and mapped using geographical information systems (GIS. Multi-level logistic regression models accounting for repeated observations within participants were used to test for associations between each land-use category (road/track/path, other man-made, greenspace, other natural and moderate-to-vigorous physical activity (MVPA. Thirty-nine children provided 2,782 matched data points. Over one third (37.1% of children’s school commute time was spent in MVPA. Children commuted approximately equal amounts of time via natural and man-made land-uses (50.2% and 49.8% respectively. Commuting via road/track/path was associated with increased likelihood of MVPA (Exp(B=1.23, P <0.05, but this association was not seen for commuting via other manmade land-uses. No association was noted between greenspace use and MVPA, but travelling via other natural land-uses was associated with lower odds of MVPA (Exp(B=0.32, P <0.05. Children spend equal amounts of time commuting to school via man-made and natural land-uses, yet man-made transportation route infrastructure appears to provide greater opportunities for achieving health-enhancing physical activity levels.

  8. The physical environment and health-enhancing activity during the school commute: global positioning system, geographical information systems and accelerometry.

    Science.gov (United States)

    McMinn, David; Oreskovic, Nicolas M; Aitkenhead, Matt J; Johnston, Derek W; Murtagh, Shemane; Rowe, David A

    2014-05-01

    Active school travel is in decline. An understanding of the potential determinants of health-enhancing physical activity during the school commute may help to inform interventions aimed at reversing these trends. The purpose of this study was to identify the physical environmental factors associated with health-enhancing physical activity during the school commute. Data were collected in 2009 on 166 children commuting home from school in Scotland. Data on location and physical activity were measured using global positioning systems (GPS) and accelerometers, and mapped using geographical information systems (GIS). Multi-level logistic regression models accounting for repeated observations within participants were used to test for associations between each land-use category (road/track/path, other man-made, greenspace, other natural) and moderate-to-vigorous physical activity (MVPA). Thirty-nine children provided 2,782 matched data points. Over one third (37.1%) of children's school commute time was spent in MVPA. Children commuted approximately equal amounts of time via natural and man-made land-uses (50.2% and 49.8% respectively). Commuting via road/track/path was associated with increased likelihood of MVPA (Exp(B)=1.23, P <0.05), but this association was not seen for commuting via other manmade land-uses. No association was noted between greenspace use and MVPA, but travelling via other natural land-uses was associated with lower odds of MVPA (Exp(B)=0.32, P <0.05). Children spend equal amounts of time commuting to school via man-made and natural land-uses, yet man-made transportation route infrastructure appears to provide greater opportunities for achieving health-enhancing physical activity levels.

  9. LD-Spline: Mapping SNPs on genotyping platforms to genomic regions using patterns of linkage disequilibrium

    Directory of Open Access Journals (Sweden)

    Bush William S

    2009-12-01

    Full Text Available Abstract Background Gene-centric analysis tools for genome-wide association study data are being developed both to annotate single locus statistics and to prioritize or group single nucleotide polymorphisms (SNPs prior to analysis. These approaches require knowledge about the relationships between SNPs on a genotyping platform and genes in the human genome. SNPs in the genome can represent broader genomic regions via linkage disequilibrium (LD, and population-specific patterns of LD can be exploited to generate a data-driven map of SNPs to genes. Methods In this study, we implemented LD-Spline, a database routine that defines the genomic boundaries a particular SNP represents using linkage disequilibrium statistics from the International HapMap Project. We compared the LD-Spline haplotype block partitioning approach to that of the four gamete rule and the Gabriel et al. approach using simulated data; in addition, we processed two commonly used genome-wide association study platforms. Results We illustrate that LD-Spline performs comparably to the four-gamete rule and the Gabriel et al. approach; however as a SNP-centric approach LD-Spline has the added benefit of systematically identifying a genomic boundary for each SNP, where the global block partitioning approaches may falter due to sampling variation in LD statistics. Conclusion LD-Spline is an integrated database routine that quickly and effectively defines the genomic region marked by a SNP using linkage disequilibrium, with a SNP-centric block definition algorithm.

  10. Quantum Programs as Kleisli Maps

    Directory of Open Access Journals (Sweden)

    Abraham Westerbaan

    2017-01-01

    Full Text Available Furber and Jacobs have shown in their study of quantum computation that the category of commutative C*-algebras and PU-maps (positive linear maps which preserve the unit is isomorphic to the Kleisli category of a comonad on the category of commutative C*-algebras with MIU-maps (linear maps which preserve multiplication, involution and unit. [Furber and Jacobs, 2013] In this paper, we prove a non-commutative variant of this result: the category of C*-algebras and PU-maps is isomorphic to the Kleisli category of a comonad on the subcategory of MIU-maps. A variation on this result has been used to construct a model of Selinger and Valiron's quantum lambda calculus using von Neumann algebras. [Cho and Westerbaan, 2016

  11. The nth commutativity degree of some 2-Engel groups

    Science.gov (United States)

    Yahya, Zainab; Mohd Ali, Nor Muhainiah; Sarmin, Nor Haniza; Johari, Nor Azwin

    2013-04-01

    Suppose x and y are elements of a group G. The commutativity degree of a group G is defined as the total number of pair (x, y) for which x and y commute divided by the total number of pair (x, y) which is possible. Moreover, the nth commutativity degree of a group G is the total number of pair (x, y) for which xn and y commute divided by the total number of (x, y) which is possible. In this research, all 2-Engel groups of order at most 25 are first determined. Then, the nth commutativity degree of those groups are computed.

  12. Examining the Link Between Public Transit Use and Active Commuting

    Directory of Open Access Journals (Sweden)

    Melissa Bopp

    2015-04-01

    Full Text Available Background: An established relationship exists between public transportation (PT use and physical activity. However, there is limited literature that examines the link between PT use and active commuting (AC behavior. This study examines this link to determine if PT users commute more by active modes. Methods: A volunteer, convenience sample of adults (n = 748 completed an online survey about AC/PT patterns, demographic, psychosocial, community and environmental factors. t-test compared differences between PT riders and non-PT riders. Binary logistic regression analyses examined the effect of multiple factors on AC and a full logistic regression model was conducted to examine AC. Results: Non-PT riders (n = 596 reported less AC than PT riders. There were several significant relationships with AC for demographic, interpersonal, worksite, community and environmental factors when considering PT use. The logistic multivariate analysis for included age, number of children and perceived distance to work as negative predictors and PT use, feelings of bad weather and lack of on-street bike lanes as a barrier to AC, perceived behavioral control and spouse AC were positive predictors. Conclusions: This study revealed the complex relationship between AC and PT use. Further research should investigate how AC and public transit use are related.

  13. Assessment of different route choice on commuters' exposure to air pollution in Taipei, Taiwan.

    Science.gov (United States)

    Li, Hsien-Chih; Chiueh, Pei-Te; Liu, Shi-Ping; Huang, Yu-Yang

    2017-01-01

    The purposes of this study are to develop a healthy commute map indicating cleanest route in Taipei metropolitan area for any given journey and to evaluate the pollutant doses exposed in different commuting modes. In Taiwan, there are more than 13.6 million motorcycles and 7.7 million vehicles among the 23 million people. Exposure to traffic-related air pollutants can thus cause adverse health effects. Moreover, increasing the level of physical activity during commuting and longer distances will result in inhalation of more polluted air. In this study, we utilized air pollution monitoring data (CO, SO2, NO2, PM10, and PM2.5) from Taiwan EPA's air quality monitoring stations in Taipei metropolitan area to estimate each pollutant exposure while commuting by different modes (motorcycling, bicycling, and walking). Spatial interpolation methods such as inverse distance weighting (IDW) were used to estimate each pollutant's distribution in Taipei metropolitan area. Three routes were selected to represent the variety of different daily commuting pathways. The cleanest route choice was based upon Dijkstra's algorithm to find the lowest cumulative pollutant exposure. The IDW interpolated values of CO, SO2, NO2, PM10, and PM2.5 ranged from 0.42-2.2 (ppm), 2.6-4.8 (ppb), 17.8-42.9 (ppb), 32.4-65.6 (μg/m(3)), and 14.2-38.9 (μg/m(3)), respectively. To compare with the IDW results, concentration of particulate matter (PM10, PM2.5, and PM1) along the motorcycle route was measured in real time. In conclusion, the results showed that the shortest commuting route for motorcyclists resulted in a much higher cumulative dose (PM2.5 3340.8 μg/m(3)) than the cleanest route (PM2.5 912.5 μg/m(3)). The mobile personal monitoring indicated that the motorcyclists inhaled significant high pollutants during commuting as a result of high-concentration exposure and short-duration peaks. The study could effectively present less polluted commuting routes for citizen health benefits.

  14. The PhOCoe Model--ergonomic pattern mapping in participatory design processes.

    Science.gov (United States)

    Silva e Santos, Marcello

    2012-01-01

    The discipline and practice of human factors and ergonomics is quite rich in terms of the availability of analysis, development and evaluation tools and methods for its various processes. However, we lack effective instruments to either map or regulate comprehensively and effectively, cognitive and organizational related impacts, especially the environmental ones. Moreover, when ergonomic transformations through design - such as a new workstation design or even an entire new facility - is at play, ergonomics professionals tend to stay at bay, relying solely on design professionals and engineers. There is vast empirical evidence showing that participation of ergonomists as project facilitators, may contribute to an effective professional synergy amongst the various stakeholders in a multidisciplinary venue. When that happens, everyone wins - users and designers alike -because eventual conflicts, raised up in the midst of options selection, are dissipated in exchange for more convergent design alternatives. This paper presents a method for participatory design, in which users are encouraged to actively participate in the whole design process by sharing their real work activities with the design team. The negotiated results inferred from the ergonomic action and translated into a new design, are then compiled into a "Ergonomic Pattern Manual". This handbook of ergonomics-oriented design guidelines contains essential guidelines to be consulted in recurrent design project situations in which similar patterns might be used. The main drive is simple: nobody knows better than workers themselves what an adequate workplace design solution (equipment, workstation, office layout) should be.

  15. Pattern recognition in lithology classification: modeling using neural networks, self-organizing maps and genetic algorithms

    Science.gov (United States)

    Sahoo, Sasmita; Jha, Madan K.

    2017-03-01

    Effective characterization of lithology is vital for the conceptualization of complex aquifer systems, which is a prerequisite for the development of reliable groundwater-flow and contaminant-transport models. However, such information is often limited for most groundwater basins. This study explores the usefulness and potential of a hybrid soft-computing framework; a traditional artificial neural network with gradient descent-momentum training (ANN-GDM) and a traditional genetic algorithm (GA) based ANN (ANN-GA) approach were developed and compared with a novel hybrid self-organizing map (SOM) based ANN (SOM-ANN-GA) method for the prediction of lithology at a basin scale. This framework is demonstrated through a case study involving a complex multi-layered aquifer system in India, where well-log sites were clustered on the basis of sand-layer frequencies; within each cluster, subsurface layers were reclassified into four depth classes based on the maximum drilling depth. ANN models for each depth class were developed using each of the three approaches. Of the three, the hybrid SOM-ANN-GA models were able to recognize incomplete geologic pattern more reasonably, followed by ANN-GA and ANN-GDM models. It is concluded that the hybrid soft-computing framework can serve as a promising tool for characterizing lithology in groundwater basins with missing lithologic patterns.

  16. Patterns of trunk muscle activation during walking and pole walking using statistical non-parametric mapping.

    Science.gov (United States)

    Zoffoli, Luca; Ditroilo, Massimiliano; Federici, Ario; Lucertini, Francesco

    2017-09-09

    This study used surface electromyography (EMG) to investigate the regions and patterns of activity of the external oblique (EO), erector spinae longissimus (ES), multifidus (MU) and rectus abdominis (RA) muscles during walking (W) and pole walking (PW) performed at different speeds and grades. Eighteen healthy adults undertook W and PW on a motorized treadmill at 60% and 100% of their walk-to-run preferred transition speed at 0% and 7% treadmill grade. The Teager-Kaiser energy operator was employed to improve the muscle activity detection and statistical non-parametric mapping based on paired t-tests was used to highlight statistical differences in the EMG patterns corresponding to different trials. The activation amplitude of all trunk muscles increased at high speed, while no differences were recorded at 7% treadmill grade. ES and MU appeared to support the upper body at the heel-strike during both W and PW, with the latter resulting in elevated recruitment of EO and RA as required to control for the longer stride and the push of the pole. Accordingly, the greater activity of the abdominal muscles and the comparable intervention of the spine extensors supports the use of poles by walkers seeking higher engagement of the lower trunk region. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Early patterning and blastodermal fate map of the head in the milkweed bug Oncopeltus fasciatus.

    Science.gov (United States)

    Birkan, Michael; Schaeper, Nina D; Chipman, Ariel D

    2011-01-01

    The process of head development in insects utilizes a set of widely conserved genes, but this process and its evolution are not well understood. Recent data from Tribolium castaneum have provided a baseline for an understanding of insect head development. However, work on a wider range of insect species, including members of the hemimetabolous orders, is needed in order to draw general conclusions about the evolution of head differentiation and regionalization. We have cloned and studied the expression and function of a number of candidate genes for head development in the hemipteran Oncopeltus fasciatus. These include orthodenticle, empty spiracles, collier, cap 'n' collar, and crocodile. The expression patterns of these genes show a broad conservation relative to Tribolium, as well as differences from Drosophila indicating that Tribolium + Oncopeltus represent a more ancestral pattern. In addition, our data provide a blastodermal fate map for different head regions in later developmental stages and supply us with a "roadmap" for future studies on head development in this species. © 2011 Wiley Periodicals, Inc.

  18. Mapping regional patterns of large forest fires in Wildland-Urban Interface areas in Europe.

    Science.gov (United States)

    Modugno, Sirio; Balzter, Heiko; Cole, Beth; Borrelli, Pasquale

    2016-05-01

    Over recent decades, Land Use and Cover Change (LUCC) trends in many regions of Europe have reconfigured the landscape structures around many urban areas. In these areas, the proximity to landscape elements with high forest fuels has increased the fire risk to people and property. These Wildland-Urban Interface areas (WUI) can be defined as landscapes where anthropogenic urban land use and forest fuel mass come into contact. Mapping their extent is needed to prioritize fire risk control and inform local forest fire risk management strategies. This study proposes a method to map the extent and spatial patterns of the European WUI areas at continental scale. Using the European map of WUI areas, the hypothesis is tested that the distance from the nearest WUI area is related to the forest fire probability. Statistical relationships between the distance from the nearest WUI area, and large forest fire incidents from satellite remote sensing were subsequently modelled by logistic regression analysis. The first European scale map of the WUI extent and locations is presented. Country-specific positive and negative relationships of large fires and the proximity to the nearest WUI area are found. A regional-scale analysis shows a strong influence of the WUI zones on large fires in parts of the Mediterranean regions. Results indicate that the probability of large burned surfaces increases with diminishing WUI distance in touristic regions like Sardinia, Provence-Alpes-Côte d'Azur, or in regions with a strong peri-urban component as Catalunya, Comunidad de Madrid, Comunidad Valenciana. For the above regions, probability curves of large burned surfaces show statistical relationships (ROC value > 0.5) inside a 5000 m buffer of the nearest WUI. Wise land management can provide a valuable ecosystem service of fire risk reduction that is currently not explicitly included in ecosystem service valuations. The results re-emphasise the importance of including this ecosystem service

  19. Commuting quantum circuits: efficient classical simulations versus hardness results

    CERN Document Server

    Ni, Xiaotong

    2012-01-01

    The study of quantum circuits composed of commuting gates is particularly useful to understand the delicate boundary between quantum and classical computation. Indeed, while being a restricted class, commuting circuits exhibit genuine quantum effects such as entanglement. In this paper we show that the computational power of commuting circuits exhibits a surprisingly rich structure. First we show that every 2-local commuting circuit acting on d-level systems and followed by single-qudit measurements can be efficiently simulated classically with high accuracy. In contrast, we prove that such strong simulations are hard for 3-local circuits. Using sampling methods we further show that all commuting circuits composed of exponentiated Pauli operators e^{i\\theta P} can be simulated efficiently classically when followed by single-qubit measurements. Finally, we show that commuting circuits can efficiently simulate certain non-commutative processes, related in particular to constant-depth quantum circuits. This give...

  20. Commuting in a polycentric city

    CERN Document Server

    Roth, Camille; Batty, Michael; Barthelemy, Marc

    2010-01-01

    The spatial arrangement of urban hubs and centers and how individuals interact with these centers is a crucial problem with many applications ranging from urban planning to epidemiology. We utilize here in an unprecedented manner the large scale, real-time 'Oyster' card database of individual person movements in the London subway to reveal the structure and organization of the city. We show that patterns of intraurban movement are strongly heterogeneous in terms of volume, but not in distance, and that there is a polycentric structure composed of simple flow patterns organized around a limited number of activity centers arranged in a hierarchical way. This new understanding can shed light on the impact of new urban projects on the evolution of the polycentric configuration of a city and provides an initial approach to modeling flows in an urban system.

  1. Development of an Advanced Public Transportation System for captive commuters on urban arterials in Ilorin, Nigeria

    Directory of Open Access Journals (Sweden)

    Oluwafemi O. Adeleke

    2013-09-01

    Full Text Available The study developed an Advanced Public Transportation System (APTS software package that serves as an intelligent movement system for captive commuters. Although a typical APTS has an Automated Trip Scheduling System (ATSS, a Digital Geographic Database (DGD, and an Automated Vehicle Location Equipment (AVLE as subsystems, the fact that vehicles in the study area are not equipped with AVLE made the authors to design for an APTS that has only the ATSS and DGD components. The ATSS subsystem has the specific objectives of reducing commuters waiting time at bus terminals, automating trip booking thus assuring a passenger of the availability of a bus and also keeps an inventory of passengers and trips made by commuters and the vehicles. The DGD allows maps of the service area to be displayed to the scheduler/operator and the commuters/clients on computer screen. The Ilorin metropolis a typical urban center in Nigeria, a developing economy, is used as the study area. Nigeria stands to benefit from ITS potentials if the developed package is put to use by urban transit operators.

  2. Dynamics in Braess Paradox with Nonimpulsive Commuters

    Directory of Open Access Journals (Sweden)

    Arianna Dal Forno

    2015-01-01

    the individual rationality leads to collective irrationality. In the literature, the dynamics has been analyzed when considering impulsive commuters, i.e., those who switch choice regardless of the actual difference between costs. We analyze a dynamical version of the paradox with nonimpulsive commuters, who change road proportionally to the cost difference. When only two roads are available, we provide a rigorous proof of the existence of a unique fixed point showing that it is globally attracting even if locally unstable. When a new road is added the system becomes discontinuous and two-dimensional. We prove that still a unique fixed point exists, and its global attractivity is numerically evidenced, also when the fixed point is locally unstable. Our analysis adds a new insight in the understanding of dynamics in social dilemma.

  3. Non-commutative time-frequency tomography

    CERN Document Server

    Man'ko, V I

    1999-01-01

    The characterization of non-stationary signals requires joint time and frequency information. However, time (t) and frequency (omega) being non-commuting variables there cannot be a joint probability density in the (t,omega) plane and the time-frequency distributions, that have been proposed, have difficult interpretation problems arising from negative or complex values and spurious components. As an alternative we propose to obtain time-frequency information by looking at the marginal distributions along rotated directions in the (t,omega) plane. The rigorous probability interpretation of the marginal distributions avoids all interpretation ambiguities. Applications to signal analysis and signal detection are discussed as well as an extension of the method to other pairs of non-commuting variables.

  4. Statistical-mechanical analysis of self-organization and pattern formation during the development of visual maps

    Science.gov (United States)

    Obermayer, K.; Blasdel, G. G.; Schulten, K.

    1992-05-01

    We report a detailed analytical and numerical model study of pattern formation during the development of visual maps, namely, the formation of topographic maps and orientation and ocular dominance columns in the striate cortex. Pattern formation is described by a stimulus-driven Markovian process, the self-organizing feature map. This algorithm generates topologically correct maps between a space of (visual) input signals and an array of formal ``neurons,'' which in our model represents the cortex. We define order parameters that are a function of the set of visual stimuli an animal perceives, and we demonstrate that the formation of orientation and ocular dominance columns is the result of a global instability of the retinoptic projection above a critical value of these order parameters. We characterize the spatial structure of the emerging patterns by power spectra, correlation functions, and Gabor transforms, and we compare model predictions with experimental data obtained from the striate cortex of the macaque monkey with optical imaging. Above the critical value of the order parameters the model predicts a lateral segregation of the striate cortex into (i) binocular regions with linear changes in orientation preference, where iso-orientation slabs run perpendicular to the ocular dominance bands, and (ii) monocular regions with low orientation specificity, which contain the singularities of the orientation map. Some of these predictions have already been verified by experiments.

  5. Ride quality systems for commuter aircraft

    Science.gov (United States)

    Downing, D. R.; Hammond, T. A.; Amin, S. P.

    1983-01-01

    The state-of-the-art in Active Ride Augmentation, specifically in terms of its feasibility for commuter aircraft applications. A literature survey was done, and the principal results are presented here through discussion of different Ride Quality Augmentation System (RQAS) designs and advances in related technologies. Recommended follow-on research areas are discussed, and a preliminary RQAS configuration for detailed design and development is proposed.

  6. Delayed Commutation in Quantum Computer Networks

    Science.gov (United States)

    García-Escartín, Juan Carlos; Chamorro-Posada, Pedro

    2006-09-01

    In the same way that classical computer networks connect and enhance the capabilities of classical computers, quantum networks can combine the advantages of quantum information and communication. We propose a nonclassical network element, a delayed commutation switch, that can solve the problem of switching time in packet switching networks. With the help of some local ancillary qubits and superdense codes, we can route a qubit packet after part of it has left the network node.

  7. Delayed commutation in quantum computer networks

    CERN Document Server

    Garcia-Escartin, J C; Chamorro-Posada, Pedro; Garcia-Escartin, Juan Carlos

    2005-01-01

    In the same way that classical computer networks connect and enhance the capabilities of classical computers, quantum networks can combine the advantages of quantum information and communications. We propose a non-classical network element, a delayed commutation switch, that can solve the problem of switching time in packet switching networks. With the help of some local ancillary qubits and superdense codes we can route the information after part of it has left the network node.

  8. Commuter Air Carrier Loan Guarantee Study.

    Science.gov (United States)

    1980-01-01

    more of an art than a science, all appeared to use six primary factors in evaluating credit worthiness. These factors were management capability...of size. The lighter twin piston commuter aircraft (Piper Aztec , Cessna 310, etc.) were assumed to have essentially a full IFR panel with autopilot...should be emphasized that each institution contacted indicated that credit evaluation is much more of an art than a science. Although quantitative

  9. Finite dimensional quotients of commutative operator algebras

    OpenAIRE

    Meyer, Ralf

    1997-01-01

    The matrix normed structure of the unitization of a (non-selfadjoint) operator algebra is determined by that of the original operator algebra. This yields a classification up to completely isometric isomorphism of two-dimensional unital operator algebras. This allows to define invariant distances on the spectrum of commutative operator algebras analogous to the Caratheodory distance for complex manifolds. Moreover, unitizations of two-dimensional operator algebras with zero multiplication pro...

  10. Expanded commuting in the metropolitan region of Belo Horizonte: evidence for reverse commuting

    Directory of Open Access Journals (Sweden)

    Carlos Lobo

    2015-08-01

    Full Text Available AbstractLarge Brazilian cities, particularly those that have experienced rapid population growth since the middle of the last century, have exhibited significant signs of population dispersion in their peripheries in recent decades. A study of the population’s spatial redistribution in the Metropolitan Region of Belo Horizonte (MRBH confirms this finding. In the process of dispersion, the levels of urban commuting increase, and commuting becomes a relevant indicator of the degree of integration within the metropolis. This paper evaluates the current magnitude and main features of reverse commuting, as characterized by the daily displacements of the population that resides not in the periphery but rather in the core. Flows from the metropolitan core towards the peripheral municipalities are examined using sample microdata on the MRBH municipalities from the 2000 and 2010 demographic censuses by combining the variables of "municipality of residence" and "municipality of work/study." The results indicate an increase in reverse commuting in both absolute and relative terms. When this flow is compared totraditional commuting (periphery/center, the relative values are considerable. In some cases, this relationship reaches notably high values, as the case of Confins (the municipality where the international airport is located, and also municipalities that are part of a relatively old conurbation, such as Nova Lima and Betim.

  11. Classical mechanics in non-commutative phase space

    Institute of Scientific and Technical Information of China (English)

    WEI Gao-Feng; LONG Chao-Yun; LONG Zheng-Wen; QIN Shui-Jie; Fu Qiang

    2008-01-01

    In this paper the laws of motion of classical particles have been investigated in a non-commutative phase space.The corresponding non-commutative relations contain not only spatial non-commutativity but also momentum non-commutativity.First,new Poisson brackets have been defined in non-commutative phase space.They contain corrections due to the non-commutativity of coordinates and momenta.On the basis of this new Poisson brackets,a new modified second law of Newton has been obtained.For two cases,the free particle and the harmonic oscillator,the equations of motion are derived on basis of the modified second law of Newton and the linear transformation (Phys.Rev.D,2005,72:025010).The consistency between both methods is demonstrated.It is shown that a free particle in commutative space is not a free particle with zero-acceleration in the non-commutative phase space.but it remains a free particle with zero-acceleration in non-commutative space if only the coordinates are non-commutative.

  12. Multi-instrument Method to Map Spatial and Temporal Patterns of Snowmelt Infiltration

    Science.gov (United States)

    Hyde, K.; Beverly, D.; Thayer, D.; Speckman, H. N.; Parsekian, A.; Kelleners, T.

    2015-12-01

    Mapping spatial patterns of relative soil moisture over time may improve understanding of snowmelt infiltration processes in heterogeneous systems. Conventional soil water measurement methods disturb soil properties and rocky materials generally limit installation of monitoring instruments to shallow depths in mountainous landscapes with snowmelt dominated hydrology. Modifications to existing technology combined with low impact installation methods provide high temporal and spatial resolution of relative soil moisture as well as a temperature profile and water table level. Closely spaced (10cm) electrical resistance pads are combined in a small diameter (2.54 cm) tube with temperature probes each 50cm, a pressure transducer, and a tube to extract groundwater for stable isotope analysis. This vertical probe array (VPA) extends 3.2m and is installed in a small diameter (4 cm) bore using a backpack drill limiting soil disturbance. Two VPAs are installed in the Snowy Range of Wyoming, one in a forested mountainous environment impacted by mortality by insects and disease and the other (limited to resistance pads only) in recently burned sagelands. Each VPA is co-located with meteorological stations. Eddy-covariance, sap flux, electrical resistivity, snowpack survey, and other hillslope eco-hydrology measurements accompany the fully instrumented VPA. Data are sampled and recorded at 5 or 15 minute intervals starting in December 2014. Over the winter both sites exhibit highly variable patterns of relatively dry soils with steady increase in wetness. Abrupt increases in relative wetness occurred with short periods of warming temperatures in Spring. Following a temperature increase in the forested site the relative moisture dramatically increased over a period of several hours at all depths as water level rose 1m within 8 hours. In contrast, following snowmelt relative moisture in the sageland site increased gradually and systematically with depth over a period of two weeks

  13. The World Stress Map Database Release 2016 - Global Crustal Stress Pattern vs. Absolute Plate Motion

    Science.gov (United States)

    Heidbach, Oliver; Rajabi, Mojtaba; Ziegler, Moritz; Reiter, Karsten

    2016-04-01

    The World Stress Map (WSM) Project was initiated in 1986 under the auspices of the International Lithosphere Program in order to compile the global information on the contemporary crustal stress state. The data come from a wide range of stress indicators such as borehole data (e.g. hydraulic fracturing, borehole breakouts), earthquake focal mechanism solutions, engineering methods (e.g. overcoring), and geological data (e.g. inversion of fault slip measurements). To guarantee the comparability of the different data sources each data record is assessed with the WSM quality ranking scheme. For the 30th anniversary we compiled a new WSM database with 42,410 data records which is an increase by >20,000 data records compared to the WSM 2008 database. In particular we added new data from more than 3,500 deep boreholes and put special emphasis on regions which previously had sparse or no published stress data such as China, Australia, Brazil, Southern Africa, Middle East and Iceland. Furthermore, we fully integrated the Chinese stress database and the Australian stress database. The resulting data increase reveals several areas with regional and local variability of the stress pattern. In particular we re-visited the question whether the plate boundary forces are the key control of the plate-wide stress pattern as indicated by the first release of the WSM in 1989 [Zoback et al, 1989]. As the WSM has now more than 10 times data records and thus a better spatial coverage we first filter the long-wave length stress pattern on a regular grid. We determine at these grid points the difference between absolute plate motion azimuth using the global plate model HS3-NUVEL1A [Gripp and Gordon, 2002] and the mean orientation of the maximum horizontal stress. The preliminary results show that the earlier findings are still valid in principal. However, all plates show in some parts significant deviations from this general trend; some plates such as the Australian Plate show hardly any

  14. CapsidMaps: protein-protein interaction pattern discovery platform for the structural analysis of virus capsids using Google Maps.

    Science.gov (United States)

    Carrillo-Tripp, Mauricio; Montiel-García, Daniel Jorge; Brooks, Charles L; Reddy, Vijay S

    2015-04-01

    Structural analysis and visualization of protein-protein interactions is a challenging task since it is difficult to appreciate easily the extent of all contacts made by the residues forming the interfaces. In the case of viruses, structural analysis becomes even more demanding because several interfaces coexist and, in most cases, these are formed by hundreds of contacting residues that belong to multiple interacting coat proteins. CapsidMaps is an interactive analysis and visualization tool that is designed to benefit the structural virology community. Developed as an improved extension of the φ-ψ Explorer, here we describe the details of its design and implementation. We present results of analysis of a spherical virus to showcase the features and utility of the new tool. CapsidMaps also facilitates the comparison of quaternary interactions between two spherical virus particles by computing a similarity (S)-score. The tool can also be used to identify residues that are solvent exposed and in the process of locating antigenic epitope regions as well as residues forming the inside surface of the capsid that interact with the nucleic acid genome. CapsidMaps is part of the VIPERdb Science Gateway, and is freely available as a web-based and cross-browser compliant application at http://viperdb.scripps.edu.

  15. Shadow of a charged rotating non-commutative black hole

    Energy Technology Data Exchange (ETDEWEB)

    Sharif, M. [University of the Punjab, Department of Mathematics, Lahore (Pakistan); Pakistan Academy of Sciences, Islamabad (Pakistan); Iftikhar, Sehrish [University of the Punjab, Department of Mathematics, Lahore (Pakistan)

    2016-11-15

    This paper investigates the shadow of a charged rotating non-commutative black hole. For this purpose, we first formulate the null geodesics and study the effects of a non-commutative charge on the photon orbit. We then explore the effect of spin, angle of inclination as well as non-commutative charge on the silhouette of the shadow. It is found that shape of the shadow deviates from the circle with the decrease in the non-commutative charge. We also discuss observable quantities to study the deformation and distortion in the shadow cast by the black hole which decreases for small values of a non-commutative charge. Finally, we study the shadows in the presence of plasma. We conclude that the non-commutativity has a great impact on the black hole shadow. (orig.)

  16. Exploring the thermodynamics of non-commutative scalar fields

    CERN Document Server

    Brito, Francisco A

    2015-01-01

    We study the thermodynamic properties of the Bose-Einstein condensate (BEC) in the context of the quantum field theory with non-commutative target space. Our main goal is to investigate in which temperature and/or energy regimes the non-commutativity can characterize some influence in the BEC properties described by a relativistic massive non-commutative boson gas. The non-commutative parameters play a key role in the modified dispersion relations of the non-commutative fields, leading to a new phenomenology. We have obtained the condensate fraction, internal energy, pressure and specific heat of the system and taken ultra-relativistic (UR) and non-relativistic limits (NR). The non-commutative effects in the thermodynamic properties of the system are discussed. We found that there appear interesting signatures around the critical temperature.

  17. Brownian Motion in Non-Commutative Super-Yang-Mills

    CERN Document Server

    Fischler, Willy; Garcia, Walter Tangarife

    2012-01-01

    Using the gauge/gravity correspondence, we study the dynamics of a heavy quark in strongly-coupled non-commutative Super-Yang-Mills at finite temperature. We propose a Langevin equation that accounts for the effects of non-commutativity and resembles the structure of Brownian motion in the presence of a magnetic field. As expected, fluctuations along non-commutative directions are generically correlated. Our results show that the viscosity of the plasma is smaller than the commutative case and that the diffusion properties of the quark are unaffected by non-commutativity. Finally, we compute the random force autocorrelator and verify that the fluctuation-dissipation theorem holds in the presence of non-commutativity.

  18. Exploring characteristics and motives of long distance commuter cyclists

    DEFF Research Database (Denmark)

    Hansen, Karsten Bruun; Sick Nielsen, Thomas

    2014-01-01

    , commuter cyclists (45 km from home to work) have more mobility options, higher incomes, and a longer education than other commuter cyclists. The main motive for longer distance cycling is physical exercise, followed by reduced costs and time used for traveling. The long distance commuter cyclists surveyed......Longer distance cycling is a commuting mode that contributes to sustainability and public health objectives, but little is known about current long distance cyclist's motives. The paper explores longer distance commuter cyclists, their characteristics, practice and motives. Longer distance...... are very positive about their commute - pointing to positive experiences, better mood, and stress relief as experiences related to their cycle trip to work. Policy support should devote attention to unlocking the potential that may be embedded in individuals combining their exercise and travel time...

  19. Shadow of a Charged Rotating Non-Commutative Black Hole

    CERN Document Server

    Sharif, M

    2016-01-01

    This paper investigates the shadow of a charged rotating non-commutative black hole. For this purpose, we first formulate the null geodesics and study the effects of non-commutative charge on the photon orbit. We then explore the effect of spin, angle of inclination as well as non-commutative charge on the silhouette of the shadow. It is found that shape of the shadow deviates from the circle with the decrease in the non-commutative charge. We also discuss observable quantities to study the deformation and distortion in the shadow cast by the black hole which decreases for small values of non-commutative charge. Finally, we study the shadows in the presence of plasma. We conclude that the non-commutativity has a great impact on the black hole shadow.

  20. 14 CFR 298.52 - Air taxi operations by commuter air carriers.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Air taxi operations by commuter air... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS EXEMPTIONS FOR AIR TAXI AND COMMUTER AIR CARRIER OPERATIONS Commuter Air Carrier Authorizations § 298.52 Air taxi operations by commuter air carriers. (a) A commuter...

  1. Non-commutative computer algebra and molecular computing

    Directory of Open Access Journals (Sweden)

    Svetlana Cojocaru

    2001-12-01

    Full Text Available Non-commutative calculations are considered from the molecular computing point of view. The main idea is that one can get more advantage in using molecular computing for non-commutative computer algebra compared with a commutative one. The restrictions, connected with the coefficient handling in Grobner basis calculations are investigated. Semigroup and group cases are considered as more appropriate. SAGBI basis constructions and possible implementations are discussed.

  2. A review of non-commutative gauge theories

    Indian Academy of Sciences (India)

    N G Deshpande

    2003-02-01

    Construction of quantum field theory based on operators that are functions of non-commutative space-time operators is reviewed. Examples of 4 theory and QED are then discussed. Problems of extending the theories to () gauge theories and arbitrary charges in QED are considered. Construction of standard model on non-commutative space is then briefly discussed. The phenomenological implications are then considered. Limits on non-commutativity from atomic physics as well as accelerator experiments are presented.

  3. On the Commutativity of a Certain Class of Toeplitz Operators

    Directory of Open Access Journals (Sweden)

    Louhichi Issam

    2014-01-01

    Full Text Available One of the major goals in the theory of Toeplitz operators on the Bergman space over the unit disk D in the complex place C is to completely describe the commutant of a given Toeplitz operator, that is, the set of all Toeplitz operators that commute with it. Here we shall study the commutants of a certain class of quasihomogeneous Toeplitz operators defined on the harmonic Bergman space.

  4. Non-commutative computer algebra and molecular computing

    OpenAIRE

    2001-01-01

    Non-commutative calculations are considered from the molecular computing point of view. The main idea is that one can get more advantage in using molecular computing for non-commutative computer algebra compared with a commutative one. The restrictions, connected with the coefficient handling in Grobner basis calculations are investigated. Semigroup and group cases are considered as more appropriate. SAGBI basis constructions and possible implementations are discussed.

  5. The topological AC effect on non-commutative phase space

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kang [Hangzhou Teachers College, Department of Physics, Hangzhou (China); The Abdus Salam International Center for Theoretical Physics, Trieste (Italy); Wang, Jianhua [Shaanxi University of Technology, Department of Physics, Hanzhong (China); The Abdus Salam International Center for Theoretical Physics, Trieste (Italy)

    2007-05-15

    The Aharonov-Casher (AC) effect in non-commutative (NC) quantum mechanics is studied. Instead of using the star product method, we use a generalization of Bopp's shift method. After solving the Dirac equations both on non-commutative space and non-commutative phase space by the new method, we obtain corrections to the AC phase on NC space and NC phase space, respectively. (orig.)

  6. On a weighted Toeplitz operator and its commutant

    Directory of Open Access Journals (Sweden)

    Vasile Lauric

    2005-05-01

    Full Text Available We study the structure of a class of weighted Toeplitz operators and obtain a description of the commutant of each operator in this class. We make some progress towards proving that the only operator in the commutant which is not a scalar multiple of the identity operator and which commutes with a nonzero compact operator is zero. The proof of the main statement relies on a conjecture which is left as an open problem.

  7. Distance Traveled and Cross-State Commuting to Opioid Treatment Programs in the United States

    Directory of Open Access Journals (Sweden)

    Andrew Rosenblum

    2011-01-01

    Full Text Available This study examined commuting patterns among 23,141 methadone patients enrolling in 84 opioid treatment programs (OTPs in the United States. Patients completed an anonymous one-page survey. A linear mixed model analysis was used to predict distance traveled to the OTP. More than half (60% the patients traveled <10 miles and 6% travelled between 50 and 200 miles to attend an OTP; 8% travelled across a state border to attend an OTP. In the multivariate model (n=17,792, factors significantly (P<.05 associated with distance were, residing in the Southeast or Midwest, low urbanicity, area of the patient's ZIP code, younger age, non-Hispanic white race/ethnicity, prescription opioid abuse, and no heroin use. A significant number of OTP patients travel considerable distances to access treatment. To reduce obstacles to OTP access, policy makers and treatment providers should be alert to patients' commuting patterns and to factors associated with them.

  8. Distance Traveled and Cross-State Commuting to Opioid Treatment Programs in the United States

    Science.gov (United States)

    Rosenblum, Andrew; Cleland, Charles M.; Fong, Chunki; Kayman, Deborah J.; Tempalski, Barbara; Parrino, Mark

    2011-01-01

    This study examined commuting patterns among 23,141 methadone patients enrolling in 84 opioid treatment programs (OTPs) in the United States. Patients completed an anonymous one-page survey. A linear mixed model analysis was used to predict distance traveled to the OTP. More than half (60%) the patients traveled <10 miles and 6% travelled between 50 and 200 miles to attend an OTP; 8% travelled across a state border to attend an OTP. In the multivariate model (n = 17,792), factors significantly (P < .05) associated with distance were, residing in the Southeast or Midwest, low urbanicity, area of the patient's ZIP code, younger age, non-Hispanic white race/ethnicity, prescription opioid abuse, and no heroin use. A significant number of OTP patients travel considerable distances to access treatment. To reduce obstacles to OTP access, policy makers and treatment providers should be alert to patients' commuting patterns and to factors associated with them. PMID:21776440

  9. Commuter networks and community detection: a method for planning sub regional areas

    CERN Document Server

    De Montis, Andrea; Chessa, Alessandro

    2011-01-01

    A major issue for policy makers and planners is the definition of the "ideal" regional partition, i.e. the delimitation of sub-regional domains showing a sufficient level of homogeneity with respect to some specific territorial features. In Sardinia, the second major island in the Mediterranean sea, politicians and analysts have been involved in a 50 year process of identification of the correct pattern for the province, an intermediate administrative body in between the Regional and the municipal administration. In this paper, we compare some intermediate body partitions of Sardinia with the patterns of the communities of workers and students, by applying grouping methodologies based on the characterization of Sardinian commuters' system as a complex weighted network. We adopt an algorithm based on the maximization of the weighted modularity of this network to detect productive basins composed by municipalities showing a certain degree of cohesiveness in terms of commuter flows. The results obtained lead to ...

  10. Impact of Megacity Jobs-Housing Spatial Mismatch on Commuting Behaviors: A Case Study on Central Districts of Shanghai, China

    Directory of Open Access Journals (Sweden)

    Xiang Zhou

    2016-01-01

    Full Text Available This studyutilized the mobile signaling data to conductthe impact analysis of jobs-housing spatial mismatch on commuting behavior, with eight typical employment centers of three categories selected as the research subjects. Based on the analysis of the characteristics and indictors including commuting distance, accessibilities from cumulative opportunity model etc., this study demonstrates that (a cumulative percentage of short commuting distance (e.g., less than 3 km reflects the jobs-housing spatial match between employment centers and their peripheral areas; and (b combining the indicators of employed population and area covered within a certain space-time range among indictors of accessibility, it is possible to identify the degree of jobs-housing balance and efficiency of the transport system. According to the evaluation radar maps, the authors believe that employment centers could be divided into three categories: those with a gathering power, those with improvable functions, and those with local adjustment potentials. Possible measures including controlling the gathering power of the city centers, improving the function mix and transport facilities, and optimizing the overall local environment, etc. could be made to achieve jobs-housing balance in central districts and their peripheral areas as a whole. Besides, the study, proceeding from the perspective of commuters, suggests that optimization of jobs-housing distribution along banded corridors would be more efficient than those within the traditional region so as to reduce commuting traffic load.

  11. A comparative physical map reveals the pattern of chromosomal evolution between the turkey (Meleagris gallopavo and chicken (Gallus gallus genomes

    Directory of Open Access Journals (Sweden)

    Delany Mary E

    2011-09-01

    Full Text Available Abstract Background A robust bacterial artificial chromosome (BAC-based physical map is essential for many aspects of genomics research, including an understanding of chromosome evolution, high-resolution genome mapping, marker-assisted breeding, positional cloning of genes, and quantitative trait analysis. To facilitate turkey genetics research and better understand avian genome evolution, a BAC-based integrated physical, genetic, and comparative map was developed for this important agricultural species. Results The turkey genome physical map was constructed based on 74,013 BAC fingerprints (11.9 × coverage from two independent libraries, and it was integrated with the turkey genetic map and chicken genome sequence using over 41,400 BAC assignments identified by 3,499 overgo hybridization probes along with > 43,000 BAC end sequences. The physical-comparative map consists of 74 BAC contigs, with an average contig size of 13.6 Mb. All but four of the turkey chromosomes were spanned on this map by three or fewer contigs, with 14 chromosomes spanned by a single contig and nine chromosomes spanned by two contigs. This map predicts 20 to 27 major rearrangements distinguishing turkey and chicken chromosomes, despite up to 40 million years of separate evolution between the two species. These data elucidate the chromosomal evolutionary pattern within the Phasianidae that led to the modern turkey and chicken karyotypes. The predominant rearrangement mode involves intra-chromosomal inversions, and there is a clear bias for these to result in centromere locations at or near telomeres in turkey chromosomes, in comparison to interstitial centromeres in the orthologous chicken chromosomes. Conclusion The BAC-based turkey-chicken comparative map provides novel insights into the evolution of avian genomes, a framework for assembly of turkey whole genome shotgun sequencing data, and tools for enhanced genetic improvement of these important agricultural and

  12. Self-commutating converters for high power applications

    CERN Document Server

    Arrillaga, Jos; Watson, Neville R; Murray, Nicholas J

    2010-01-01

    For very high voltage or very high current applications, the power industry still relies on thyristor-based Line Commutated Conversion (LCC), which limits the power controllability to two quadrant operation. However, the ratings of self-commutating switches such as the Insulated-Gate Bipolar Transistor (IGBT) and Integrated Gate-Commutated Thyristor (IGCT), are reaching levels that make the technology possible for very high power applications. This unique book reviews the present state and future prospects of self-commutating static power converters for applications requiring either ultr

  13. Can non-commutativity resolve the big-bang singularity?

    Energy Technology Data Exchange (ETDEWEB)

    Maceda, M.; Madore, J. [Laboratoire de Physique Theorique, Universite de Paris-Sud, Batiment 211, 91405, Orsay (France); Manousselis, P. [Department of Engineering Sciences, University of Patras, 26110, Patras (Greece); Physics Department, National Technical University, Zografou Campus, 157 80, Zografou, Athens (Greece); Zoupanos, G. [Physics Department, National Technical University, Zografou Campus, 157 80, Zografou, Athens (Greece); Theory Division, CERN, 1211, Geneva 23 (Switzerland)

    2004-08-01

    A possible way to resolve the singularities of general relativity is proposed based on the assumption that the description of space-time using commuting coordinates is not valid above a certain fundamental scale. Beyond that scale it is assumed that the space-time has non-commutative structure leading in turn to a resolution of the singularity. As a first attempt towards realizing the above programme a modification of the Kasner metric is constructed which is commutative only at large time scales. At small time scales, near the singularity, the commutation relations among the space coordinates diverge. We interpret this result as meaning that the singularity has been completely delocalized. (orig.)

  14. Geometry, commutation relations and the quantum fictitious force

    DEFF Research Database (Denmark)

    Botero, J.; Cirone, M.A.; Dahl, Jens Peder

    2003-01-01

    We express the commutation relation between the operators of the momentum and the radial unit vectors in D dimensions in differential and integral form. We connect this commutator with the quantum fictitious potential emerging in the radial Schrodinger equation of an s-wave.......We express the commutation relation between the operators of the momentum and the radial unit vectors in D dimensions in differential and integral form. We connect this commutator with the quantum fictitious potential emerging in the radial Schrodinger equation of an s-wave....

  15. A reconstruction theorem for almost-commutative spectral triples

    CERN Document Server

    Ćaćić, Branimir

    2011-01-01

    We propose an expansion of the definition of almost-commutative spectral triple that accommodates non-trivial fibrations and is stable under inner fluctuation of the metric, and then prove a reconstruction theorem for almost-commutative spectral triples under this definition as a simple consequence of the reconstruction theorem for commutative spectral triples. Along the way, we weaken the orientability hypothesis in Connes's reconstruction theorem for commutative spectral triples, and, following Chakraborty and Mathai, prove a number of results concerning the stability of properties of spectral triples under suitable perturbation of the Dirac operator.

  16. Design a light pattern of multiple concentric circles for LED fishing lamps using Fourier series and an energy mapping method.

    Science.gov (United States)

    Shen, S C; Li, J S; Huang, M C

    2014-06-02

    Fourier series and an energy mapping method were used in this study to design a lens that produces a light pattern of multiple concentric circles (LPMCC) for a light-emitting diode (LED) fishing lamp. Fourier series were used to represent the light intensity distribution curve (LIDC) of the LPMCC light pattern. Energy mapping involves performing angular energy mapping based on the LIDCs of an LED light source and LPMCC to design a freeform lens. Type I and Type II LPMCC lenses were designed according to the phototaxis behavior of fish to create a LPMCC light pattern of interleaving light-dark zones that attracts fish shoals to stay in an area for a long period. The experimental results indicated that, in comparing the LIDCs of the Type I and II lenses with the respective simulation values, the normalized cross-correlation (NCC) value reached 96%. According to a 24-hour observation of the phototaxis of Poecilia reticulata to evaluate the effectiveness of the proposed light pattern to attract fish, when a fish shoal was habituated to a light source that emitted constant illumination light, it gradually moved away from the intense light zone and hovered around the junction of the light and dark zones. In the future, the design used in this study can be applied to LED fishing lamps to replace traditional fishing lamps.

  17. Probabilistic seismic hazard maps from seismicity patterns analysis: the Iberian Peninsula case

    Directory of Open Access Journals (Sweden)

    A. Jiménez

    2004-01-01

    Full Text Available Earthquake prediction is a main topic in Seismology. Here, the goal is to know the correlation between the seismicity at a certain place at a given time with the seismicity at the same place, but at a following interval of time. There are no ways for exact predictions, but one can wonder about the causality relations between the seismic characteristics at a given time interval and another in a region. In this paper, a new approach to this kind of studies is presented. Tools which include cellular automata theory and Shannon's entropy are used. First, the catalogue is divided into time intervals, and the region into cells. The activity or inactivity of each cell at a certain time is described using an energy criterion; thus a pattern which evolves over time is given. The aim is to find the rules of the stochastic cellular automaton which best fits the evolution of the pattern. The neighborhood utilized is the cross template (CT. A grid search is made to choose the best model, being the mutual information between the different times the function to be maximized. This function depends on the size of the cells β on and the interval of time τ which is considered for studying the activity of a cell. With these β and τ, a set of probabilities which characterizes the evolution rules is calculated, giving a probabilistic approach to the spatiotemporal evolution of the region. The sample catalogue for the Iberian Peninsula covers since 1970 till 2001. The results point out that the seismic activity must be deduced not only from the past activity at the same region but also from its surrounding activity. The time and spatial highest interaction for the catalogue used are of around 3.3 years and 290x165 km2, respectively; if a cell is inactive, it will continue inactive with a high probability; an active cell has around the 60% probability of continuing active in the future. The Probabilistic Seismic Hazard Map obtained marks the main seismic active

  18. In situ spatial patterns of soil bacterial populations, mapped at multiple scales, in an arable soil.

    Science.gov (United States)

    Nunan, N; Wu, K; Young, I M; Crawford, J W; Ritz, K

    2002-11-01

    Very little is known about the spatial organization of soil microbes across scales that are relevant both to microbial function and to field-based processes. The spatial distributions of microbes and microbially mediated activity have a high intrinsic variability. This can present problems when trying to quantify the effects of disturbance, management practices, or climate change on soil microbial systems and attendant function. A spatial sampling regime was implemented in an arable field. Cores of undisturbed soil were sampled from a 3 x 3 x 0.9 m volume of soil (topsoil and subsoil) and a biological thin section, in which the in situ distribution of bacteria could be quantified, prepared from each core. Geostatistical analysis was used to quantify the nature of spatial structure from micrometers to meters and spatial point pattern analysis to test for deviations from complete spatial randomness of mapped bacteria. Spatial structure in the topsoil was only found at the microscale (micrometers), whereas evidence for nested scales of spatial structure was found in the subsoil (at the microscale, and at the centimeter to meter scale). Geostatistical ranges of spatial structure at the micro scale were greater in the topsoil and tended to decrease with depth in the subsoil. Evidence for spatial aggregation in bacteria was stronger in the topsoil and also decreased with depth in the subsoil, though extremely high degrees of aggregation were found at very short distances in the deep subsoil. The data suggest that factors that regulate the distribution of bacteria in the subsoil operate at two scales, in contrast to one scale in the topsoil, and that bacterial patches are larger and more prevalent in the topsoil.

  19. Simulations results for U(1) gauge theory on non-commutative spaces

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, W. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Bigarini, A. [Univ. degli Studi di Perugia (Italy). Dipt. di Fisica; Nishimura, J. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan)]|[Graduate Univ. for Advanced Studies Tsukuba (Japan). Dept. of Particle and Nuclear Physics; Susaki, Y. [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan)]|[Tsukuba Univ. (Japan). Graduate School of Pure and Applied Science; Torrielli, A. [Massachusetts Institute of Technology (MIT), Cambridge, MA (United States). Center for Theoretical Physics, Lab. for Nuclear Sciences and Dept. of Physics; Volkholz, J. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik

    2007-11-15

    We present numerical results for U(1) gauge theory in 2d and 4d spaces involving a noncommutative plane. Simulations are feasible thanks to a mapping of the non-commutative plane onto a twisted matrix model. In d=2 it was a long-standing issue if Wilson loops are (partially) invariant under area-preserving diffeomorphisms. We show that non-perturbatively this invariance breaks, including the subgroup SL(2,R). In both cases, d=2 and d=4, we extrapolate our results to the continuum and infinite volume by means of a Double Scaling Limit. In d=4 this limit leads to a phase with broken translation symmetry, which is not affected by the perturbatively known IR instability. Therefore the photon may survive in a non-commutative world. (orig.)

  20. Divide and Conquer Approach to Contact Map Overlap Problem Using 2D-Pattern Mining of Protein Contact Networks.

    Science.gov (United States)

    Koneru, Suvarna Vani; Bhavani, Durga S

    2015-01-01

    A novel approach to Contact Map Overlap (CMO) problem is proposed using the two dimensional clusters present in the contact maps. Each protein is represented as a set of the non-trivial clusters of contacts extracted from its contact map. The approach involves finding matching regions between the two contact maps using approximate 2D-pattern matching algorithm and dynamic programming technique. These matched pairs of small contact maps are submitted in parallel to a fast heuristic CMO algorithm. The approach facilitates parallelization at this level since all the pairs of contact maps can be submitted to the algorithm in parallel. Then, a merge algorithm is used in order to obtain the overall alignment. As a proof of concept, MSVNS, a heuristic CMO algorithm is used for global as well as local alignment. The divide and conquer approach is evaluated for two benchmark data sets that of Skolnick and Ding et al. It is interesting to note that along with achieving saving of time, better overlap is also obtained for certain protein folds.

  1. Assessment of commuters' daily exposure to flash flooding over the roads of the Gard region, France

    Science.gov (United States)

    Debionne, Samuel; Ruin, Isabelle; Shabou, Saif; Lutoff, Céline; Creutin, Jean-Dominique

    2016-10-01

    -road dangerous intersections and (ii) not all commuters are equally exposed. Evidently commuters who have longer routes are more exposed, but residents of rural municipalities as well as professionals with highly qualified jobs are also more exposed. Finally, these exposure assessment methods applied to the Gard area allows locating road sections where commuters' exposure to flood is high. It also sets the first step toward the implementation of a modeling platform able to combine the estimation of daily travel patterns exposure and behavioral response of motorists to road flooding, a critical input for emergency services and services in charge of the management of road networks in flash flood prone areas.

  2. Future Propulsion Opportunities for Commuter Airplanes

    Science.gov (United States)

    Strack, W. C.

    1982-01-01

    Commuter airplane propulsion opportunities are summarized. Consideration is given to advanced technology conventional turboprop engines, advanced propellers, and several unconventional alternatives: regenerative turboprops, rotaries, and diesels. Advanced versions of conventional turboprops (including propellers) offer 15-20 percent savings in fuel and 10-15 percent in DOC compared to the new crop of 1500-2000 SHP engines currently in development. Unconventional engines could boost the fuel savings to 30-40 percent. The conclusion is that several important opportunities exist and, therefore, powerplant technology need not plateau.

  3. Eulerian Dynamics with a Commutator Forcing

    Science.gov (United States)

    2017-01-09

    not. The results below are stated over the torus, Ω = T1, for the purely technical reason of securing a uniform lower bound of the density away from...2.1. L∞-bound of the velocity. We assume that L satisfies the following monotonicity condition. Let x+ = arg max x g(x) and x− = arg min x g(x). Then...special case of the monotonicity condition (2.1) with (f, g) = (1, ρ) implies L(ρ)(x−) > L(1(x−))ρ− = 0. EULERIAN DYNAMICS WITH A COMMUTATOR FORCING 9 Here

  4. Gravity in Non-Commutative Geometry

    CERN Document Server

    Chamseddine, A H; Fröhlich, J

    1993-01-01

    We study general relativity in the framework of non-commutative differential geometry. In particular, we introduce a gravity action for a space-time which is the product of a four dimensional manifold by a two-point space. In the simplest situation, where the Riemannian metric is taken to be the same on the two copies of the manifold, one obtains a model of a scalar field coupled to Einstein gravity. This field is geometrically interpreted as describing the distance between the two points in the internal space.

  5. The quaternionic commutator bracket and its implications

    CERN Document Server

    Arbab, Arbab I

    2014-01-01

    A quaternionic commutator bracket for position and momentum shows that the quaternionic wave function, \\emph{viz.} $\\widetilde{\\psi}=(\\frac{i}{c}\\,\\psi_0\\,,\\vec{\\psi})$, represents a state of a particle with orbital angular momentum, $L=3\\,\\hbar$, resulting from the internal structure of the particle. This angular momentum can be attributed to spin of the particle. The vector $\\vec{\\psi}$, points along the direction of $\\vec{L}$. When a charged particle is placed in an electromagnetic fields the interaction energy reveals that the magnetic moments interact with the electric and magnetic fields giving rise to terms similar to Aharonov-Bohm and Aharonov-Casher effects.

  6. Sharp weighted estimates for multilinear commutators

    OpenAIRE

    Pérez Moreno, Carlos; Trujillo González, Rodrigo Francisco

    2002-01-01

    Multilinear commutators with vector symbol Formula=(b1,…,bm) defined by Formula are considered, where K is a Calderón–Zygmund kernel. The following a priori estimates are proved for w ∈ A∞. For 0 < p < ∞, there exists a constant C such that Formula and Formula where Formula Formula and ML(log L)α is an Orlicz type maximal operator. This extends, with a different approach, classical results by Coifman. As a corollary, it is deduced that the operators For...

  7. Star products from commutative string theory

    Indian Academy of Sciences (India)

    Sunil Mukhi

    2002-01-01

    A boundary-state computation is performed to obtain derivative corrections to the Chern–Simons coupling between a -brane and the RR gauge potential -3. We work to quadratic order in the gauge field strength , but all orders in derivatives. In a certain limit, which requires the presence of a constant -field background, it is found that these corrections neatly sum up into the *2 product of (commutative) gauge fields. The result is in agreement with a recent prediction using noncommutativity

  8. Spontaneous usage of different shortcuts based on the commutativity principle.

    Directory of Open Access Journals (Sweden)

    Robert Gaschler

    Full Text Available Based on research on expertise a person can be said to possess integrated conceptual knowledge when she/he is able to spontaneously identify task relevant information in order to solve a problem efficiently. Despite the lack of instruction or explicit cueing, the person should be able to recognize which shortcut strategy can be applied--even when the task context differs from the one in which procedural knowledge about the shortcut was originally acquired. For mental arithmetic, first signs of such adaptive flexibility should develop already in primary school. The current study introduces a paper-and-pencil-based as well as an eyetracking-based approach to unobtrusively measure how students spot and apply (known shortcut options in mental arithmetic. We investigated the development and the relation of the spontaneous use of two strategies derived from the mathematical concept of commutativity. Children from grade 2 to grade 7 and university students solved three-addends addition problems, which are rarely used in class. Some problems allowed the use of either of two commutativity-based shortcut strategies. Results suggest that from grade three onwards both of the shortcuts were used spontaneously and application of one shortcut correlated positively with application of the other. Rate of spontaneous usage was substantial but smaller than in an instructed variant. Eyetracking data suggested similar fixation patterns for spontaneous an instructed shortcut application. The data are consistent with the development of an integrated concept of the mathematical principle so that it can be spontaneously applied in different contexts and strategies.

  9. Commuter motorcycle crashes in Malaysia: An understanding of contributing factors.

    Science.gov (United States)

    Oxley, Jennifer; Yuen, Jeremy; Ravi, Mano Deepa; Hoareau, Effie; Mohammed, Mohammed Azman Aziz; Bakar, Harun; Venkataraman, Saraswathy; Nair, Prame Kumar

    2013-01-01

    In Malaysia, two-thirds of reported workplace-related fatal and serious injury incidents are the result of commuting crashes (especially those involving motorcyclists), however, little is known about the contributing factors to these collisions. A telephone survey of 1,750 motorcyclists (1,004 adults who had been involved in a motorcycle commuting crash in the last 2 years and 746 adult motorcyclists who had not been involved in a motorcycle crash in the last 2 years) was undertaken. The contributions of a range of behavioural, attitudinal, employment and travel pattern factors to collision involvement were examined. The findings revealed that the majority of participants were licensed riders, rode substantial distances (most often for work purposes), and reported adopting safe riding practices (helmet wearing and buckling). However, there were some concerning findings regarding speeding behaviour, use of mobile phones while riding, and engaging in other risky behaviours. Participants who had been involved in a collision were younger (aged 25-29 years), had higher exposure (measured by distances travelled, frequency of riding, and riding on high volume and higher speed roads), reported higher rates of riding for work purposes, worked more shift hours and had a higher likelihood of riding at relatively high speeds compared with participants who had not been involved in a collision. Collisions generally occurred during morning and early evening hours, striking another vehicles, and during normal traffic flow. The implications of these findings for policy decisions and development of evidence-based behavioural/training interventions addressing key contributing factors are discussed.

  10. The effect of commuting microenvironment on commuter exposures to vehicular emission in Hong Kong

    Science.gov (United States)

    Chan, L. Y.; Chan, C. Y.; Qin, Y.

    Vehicular exhaust emission has gradually become the major air pollution source in modern cities and traffic related exposure is found to contribute significantly to total human exposure level. A comprehensive survey was conducted from November 1995 to July 1996 in Hong Kong to assess the effect of traffic-induced air pollution inside different commuting microenvironments on commuter exposure. Microenvironmental monitoring is performed for six major public commuting modes (bus, light bus, MTR, railway, tram, ferry), plus private car and roadside pavement. Traffic-related pollutants, CO, NO x, THC and O 3 were selected as the target pollutants. The results indicate that commuter exposure is highly influenced by the choice of commuting microenvironment. In general, the exposure level in decreasing order of measured pollutant level for respective commuting microenvironments are: private car, the group consisting light bus, bus, tram and pavement, MTR and train, and finally ferry. In private car, the CO level is several times higher than that in the other microenvironments with a trip averaged of 10.1 ppm and a maximum of 24.9 ppm. Factors such as the body position of the vehicle, intake point of the ventilation system, fuel used, ventilation, transport mode, road and driving conditions were used in the analysis. Inter-microenvironment, intra-microenvironment and temporal variation of CO concentrations were used as the major indicator. The low body position and low intake point of the ventilation system of the private car are believed to be the cause of higher intake of exhaust of other vehicles and thus result in high pollution level in this microenvironment. Compared with other metropolis around the world and the Hong Kong Air Quality Objectives (HKAQO), exposure levels of commuter to traffic-related air pollution in Hong Kong are relatively low for most pollutants measured. Only several cases of exceedence of HKAQO by NO 2 were recorded. The strong prevailing wind

  11. Performance evaluation of partial differential equation models in electronic speckle pattern interferometry and the delta-mollification phase map method.

    Science.gov (United States)

    Tang, Chen; Zhang, Fang; Li, Botao; Yan, Haiqing

    2006-10-01

    The ordinary differential equation (ODE) and partial differential equation (PDE) image- processing methods have been applied to reduce noise and enhance the contrast of electronic speckle pattern interferometry fringe patterns. We evaluate the performance of a few representative PDE denoising models quantitatively with two parameters called image fidelity and speckle index, and then we choose a good denoising model. Combining this denoising model with the ODE enhancement method, we make it possible to perform contrast enhancement and denoising simultaneously. Second, we introduce the delta-mollification method to smooth the unwrapped phase map. Finally, based on PDE image processing, delta mollification and some traditional techniques, an approach of phase extraction from a single fringe pattern is tested for computer-simulated and experimentally obtained fringe patterns. The method works well under a high noise level and limited visibility and can extract accurate phase values.

  12. Performance evaluation of partial differential equation models in electronic speckle pattern interferometry and the δ-mollification phase map method

    Science.gov (United States)

    Tang, Chen; Zhang, Fang; Li, Botao; Yan, Haiqing

    2006-10-01

    The ordinary differential equation (ODE) and partial differential equation (PDE) image- processing methods have been applied to reduce noise and enhance the contrast of electronic speckle pattern interferometry fringe patterns. We evaluate the performance of a few representative PDE denoising models quantitatively with two parameters called image fidelity and speckle index, and then we choose a good denoising model. Combining this denoising model with the ODE enhancement method, we make it possible to perform contrast enhancement and denoising simultaneously. Second, we introduce the δ-mollification method to smooth the unwrapped phase map. Finally, based on PDE image processing, δ mollification and some traditional techniques, an approach of phase extraction from a single fringe pattern is tested for computer-simulated and experimentally obtained fringe patterns. The method works well under a high noise level and limited visibility and can extract accurate phase values.

  13. Geometry of time-spaces non-commutative algebraic geometry, applied to quantum theory

    CERN Document Server

    Landau, Olav Arnfinn

    2011-01-01

    This is a monograph about non-commutative algebraic geometry, and its application to physics. The main mathematical inputs are the non-commutative deformation theory, moduli theory of representations of associative algebras, a new non-commutative theory o

  14. Facial whisker pattern is not sufficient to instruct a whisker-related topographic map in the mouse somatosensory brainstem.

    Science.gov (United States)

    Laumonnerie, Christophe; Bechara, Ahmad; Vilain, Nathalie; Kurihara, Yukiko; Kurihara, Hiroki; Rijli, Filippo M

    2015-11-01

    Facial somatosensory input is relayed by trigeminal ganglion (TG) neurons and serially wired to brainstem, thalamus and cortex. Spatially ordered sets of target neurons generate central topographic maps reproducing the spatial arrangement of peripheral facial receptors. Facial pattern provides a necessary template for map formation, but may be insufficient to impose a brain somatotopic pattern. In mice, lower jaw sensory information is relayed by the trigeminal nerve mandibular branch, whose axons target the brainstem dorsal principal sensory trigeminal nucleus (dPrV). Input from mystacial whiskers is relayed by the maxillary branch and forms a topographic representation of rows and whiskers in the ventral PrV (vPrV). To investigate peripheral organisation in imposing a brain topographic pattern, we analysed Edn1(-/-) mice, which present ectopic whisker rows on the lower jaw. We found that these whiskers were innervated by mandibular TG neurons which initially targeted dPrV. Unlike maxillary TG neurons, the ectopic whisker-innervating mandibular neuron cell bodies and pre-target central axons did not segregate into a row-specific pattern nor target the dPrV with a topographic pattern. Following periphery-driven molecular repatterning to a maxillary-like identity, mandibular neurons partially redirected their central projections from dPrV to vPrV. Thus, while able to induce maxillary-like molecular features resulting in vPrV final targeting, a spatially ordered lower jaw ectopic whisker pattern is insufficient to impose row-specific pre-target organisation of the central mandibular tract or a whisker-related matching pattern of afferents in dPrV. These results provide novel insights into periphery-dependent versus periphery-independent mechanisms of trigeminal ganglion and brainstem patterning in matching whisker topography. © 2015. Published by The Company of Biologists Ltd.

  15. Grid Mapping for Spatial Pattern Analyses of Recurrent Urban Traffic Congestion Based on Taxi GPS Sensing Data

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2017-03-01

    Full Text Available Traffic congestion is one of the most serious problems that impact urban transportation efficiency, especially in big cities. Identifying traffic congestion locations and occurring patterns is a prerequisite for urban transportation managers in order to take proper countermeasures for mitigating traffic congestion. In this study, the historical GPS sensing data of about 12,000 taxi floating cars in Beijing were used for pattern analyses of recurrent traffic congestion based on the grid mapping method. Through the use of ArcGIS software, 2D and 3D maps of the road network congestion were generated for traffic congestion pattern visualization. The study results showed that three types of traffic congestion patterns were identified, namely: point type, stemming from insufficient capacities at the nodes of the road network; line type, caused by high traffic demand or bottleneck issues in the road segments; and region type, resulting from multiple high-demand expressways merging and connecting to each other. The study illustrated that the proposed method would be effective for discovering traffic congestion locations and patterns and helpful for decision makers to take corresponding traffic engineering countermeasures in order to relieve the urban traffic congestion issues.

  16. Mapping Major Cropping Patterns in Southeast Asia from Modis Data Using Wavelet Transform and Artificial Neural Networks

    Science.gov (United States)

    Son, N. T.; Chen, C. F.; Cru, C. R.

    2012-07-01

    Agriculture is one of the most important sectors in the economy of Southeast Asia countries, especially Thailand and Vietnam. These two countries have been the largest rice suppliers in the world and played a critical role in global food security. Yearly rice crop monitoring to provide policymakers with information on rice growing areas is thus important to timely devise plans to ensure food security. This study aimed to develop an approach for regional mapping of cropping patterns from time-series MODIS data. Data were processed through three steps: (1) noise filtering of time-series MODIS NDVI data with wavelet transform, (2) image classification of cropping patterns using artificial neural networks (ANNs), and (3) classification accuracy assessment using ground reference data. The results by a comparison between classification map and ground reference data indicated the overall accuracy of 80.3% and Kappa coefficient of 0.76.

  17. Comparative analysis of 3D expression patterns of transcription factor genes and digit fate maps in the developing chick wing.

    Directory of Open Access Journals (Sweden)

    Malcolm Fisher

    Full Text Available Hoxd13, Tbx2, Tbx3, Sall1 and Sall3 genes are candidates for encoding antero-posterior positional values in the developing chick wing and specifying digit identity. In order to build up a detailed profile of gene expression patterns in cell lineages that give rise to each of the digits over time, we compared 3 dimensional (3D expression patterns of these genes during wing development and related them to digit fate maps. 3D gene expression data at stages 21, 24 and 27 spanning early bud to digital plate formation, captured from in situ hybridisation whole mounts using Optical Projection Tomography (OPT were mapped to reference wing bud models. Grafts of wing bud tissue from GFP chicken embryos were used to fate map regions of the wing bud giving rise to each digit; 3D images of the grafts were captured using OPT and mapped on to the same models. Computational analysis of the combined computerised data revealed that Tbx2 and Tbx3 are expressed in digit 3 and 4 progenitors at all stages, consistent with encoding stable antero-posterior positional values established in the early bud; Hoxd13 and Sall1 expression is more dynamic, being associated with posterior digit 3 and 4 progenitors in the early bud but later becoming associated with anterior digit 2 progenitors in the digital plate. Sox9 expression in digit condensations lies within domains of digit progenitors defined by fate mapping; digit 3 condensations express Hoxd13 and Sall1, digit 4 condensations Hoxd13, Tbx3 and to a lesser extent Tbx2. Sall3 is only transiently expressed in digit 3 progenitors at stage 24 together with Sall1 and Hoxd13; then becomes excluded from the digital plate. These dynamic patterns of expression suggest that these genes may play different roles in digit identity either together or in combination at different stages including the digit condensation stage.

  18. Mapping the geography of science: distribution patterns and networks of relations among cities and institutes

    NARCIS (Netherlands)

    Leydesdorff, L.; Persson, O.

    2010-01-01

    Using Google Earth, Google Maps, and/or network visualization programs such as Pajek, one can overlay the network of relations among addresses in scientific publications onto the geographic map. The authors discuss the pros and cons of various options, and provide software (freeware) for bridging ex

  19. Sequential Pattern Analysis: Method and Application in Exploring How Students Develop Concept Maps

    Science.gov (United States)

    Chiu, Chiung-Hui; Lin, Chien-Liang

    2012-01-01

    Concept mapping is a technique that represents knowledge in graphs. It has been widely adopted in science education and cognitive psychology to aid learning and assessment. To realize the sequential manner in which students develop concept maps, most research relies upon human-dependent, qualitative approaches. This article proposes a method for…

  20. Mapping the geography of science: distribution patterns and networks of relations among cities and institutes

    NARCIS (Netherlands)

    Leydesdorff, L.; Persson, O.

    2010-01-01

    Using Google Earth, Google Maps, and/or network visualization programs such as Pajek, one can overlay the network of relations among addresses in scientific publications onto the geographic map. The authors discuss the pros and cons of various options, and provide software (freeware) for bridging

  1. Mapping the geography of science: distribution patterns and networks of relations among cities and institutes

    NARCIS (Netherlands)

    Leydesdorff, L.; Persson, O.

    2010-01-01

    Using Google Earth, Google Maps, and/or network visualization programs such as Pajek, one can overlay the network of relations among addresses in scientific publications onto the geographic map. The authors discuss the pros and cons of various options, and provide software (freeware) for bridging ex

  2. Mapping the spatial patterns of field traffic and traffic intensity to predict soil compaction risks at the field scale

    Science.gov (United States)

    Duttmann, Rainer; Kuhwald, Michael; Nolde, Michael

    2015-04-01

    Soil compaction is one of the main threats to cropland soils in present days. In contrast to easily visible phenomena of soil degradation, soil compaction, however, is obscured by other signals such as reduced crop yield, delayed crop growth, and the ponding of water, which makes it difficult to recognize and locate areas impacted by soil compaction directly. Although it is known that trafficking intensity is a key factor for soil compaction, until today only modest work has been concerned with the mapping of the spatially distributed patterns of field traffic and with the visual representation of the loads and pressures applied by farm traffic within single fields. A promising method for for spatial detection and mapping of soil compaction risks of individual fields is to process dGPS data, collected from vehicle-mounted GPS receivers and to compare the soil stress induced by farm machinery to the load bearing capacity derived from given soil map data. The application of position-based machinery data enables the mapping of vehicle movements over time as well as the assessment of trafficking intensity. It also facilitates the calculation of the trafficked area and the modeling of the loads and pressures applied to soil by individual vehicles. This paper focuses on the modeling and mapping of the spatial patterns of traffic intensity in silage maize fields during harvest, considering the spatio-temporal changes in wheel load and ground contact pressure along the loading sections. In addition to scenarios calculated for varying mechanical soil strengths, an example for visualizing the three-dimensional stress propagation inside the soil will be given, using the Visualization Toolkit (VTK) to construct 2D or 3D maps supporting to decision making due to sustainable field traffic management.

  3. Noise exposure during commuting in three European cities

    NARCIS (Netherlands)

    Taimisto, P.; Yli-Tuomi, T.; Pennanen, A.; Vouitsis, I.; Samaras, Z.; Keuken, M.P.; Lanki, T.

    2013-01-01

    In the TRANSPHORM study, noise exposures during commuting were measured. Measurements were performed with noise dosimeters in three European cities, Helsinki, Thessaloniki and Rotterdam, during spring 2011. ln each city, two to five approximately 8 km commuting routes were selected to represent

  4. Homogeneous Buchberger algorithms and Sullivant's computational commutative algebra challenge

    DEFF Research Database (Denmark)

    Lauritzen, Niels

    2005-01-01

    We give a variant of the homogeneous Buchberger algorithm for positively graded lattice ideals. Using this algorithm we solve the Sullivant computational commutative algebra challenge.......We give a variant of the homogeneous Buchberger algorithm for positively graded lattice ideals. Using this algorithm we solve the Sullivant computational commutative algebra challenge....

  5. Weighted weak type estimates for commutators of the Marcinkiewicz integrals

    Institute of Scientific and Technical Information of China (English)

    DING; Yong; LU; Shanzhen; ZHANG; Pu

    2004-01-01

    In this paper the authors give the weighted weak LlogL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities for the Marcinkiewicz integral and its commutators with different weight functions are also discussed.

  6. Soft commutated direct current motor [summary of proposed paper

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, John S.

    1998-10-22

    A novel soft commutated direct current (DC) motor is introduced. The current of the commutated coil is intentionally drained before the brush disconnects the coil. This prevents the spark generation that normally occurs in conventional DC motors. A similar principle can be applied for DC generators.

  7. Simplicity and maximal commutative subalgebras of twisted generalized Weyl algebras

    DEFF Research Database (Denmark)

    Hartwig, J.T.; Öinert, Per Johan

    2013-01-01

    conditions for certain TGWAs to be simple, in the case when R is commutative. We illustrate our theorems by considering some special classes of TGWAs and providing concrete examples. We also discuss how simplicity of a TGWA is related to the maximal commutativity of R and the (non-)existence of non...

  8. Parabosonic string and space-time non-commutativity

    Energy Technology Data Exchange (ETDEWEB)

    Seridi, M. A.; Belaloui, N. [Laboratoire de Physique Mathematique et Subatomique, Universite Mentouri Constantine (Algeria)

    2012-06-27

    We investigate the para-quantum extension of the bosonic strings in a non-commutative space-time. We calculate the trilinear relations between the mass-center variables and the modes and we derive the Virasoro algebra where a new anomaly term due to the non-commutativity is obtained.

  9. Parity-dependent non-commutative quantum mechanics

    Science.gov (United States)

    Chung, Won Sang

    2017-01-01

    In this paper, we consider the non-commutative quantum mechanics (NCQM) with parity (or space reflection) in two dimensions. Using the parity operators Ri, we construct the deformed Heisenberg algebra with parity in the non-commutative plane. We use this algebra to discuss the isotropic harmonic Hamiltonian with parity.

  10. The association between commuter cycling and sickness absence

    NARCIS (Netherlands)

    Hendriksen, I.J.M.; Simons, M.; Garre, F.G.; Hildebrandt, V.H.

    2010-01-01

    Objective: To study the association between commuter cycling and all-cause sickness absence, and the possible dose-response relationship between absenteeism and the distance, frequency and speed of commuter cycling. Method: Cross-sectional data about cycling in 1236 Dutch employees were collected us

  11. High-Energy Scattering in Non-Commutative Field Theory

    CERN Document Server

    Kumar, J; Kumar, Jason; Rajaraman, Arvind

    2005-01-01

    We analyze high energy scattering for non-commutative field theories using the dual gravity description. We find that the Froissart-Martin bound still holds, but that cross-sections stretch in the non-commutative directions in a way dependent on the infrared cutoff. This puzzling behavior suggests new aspects of UV/IR mixing.

  12. An Endpoint Estimate for the Commutator of Singular Integrals

    Institute of Scientific and Technical Information of China (English)

    Yong Zhong SUN; Wei Yi SU

    2005-01-01

    It is well known that the commutator Tb of the singular integral operator T with a BMO function b is bounded on Lp(Rn), 1 < p <∞. In this paper, we consider the endpoint estimates for a kind of commutator of singular integrals. A BMO-type estimate for Tb is obtained under the assumption b ∈ LMO.

  13. Positive representations of general commutation relations allowing Wick ordering

    CERN Document Server

    Jorgensen, P E T; Werner, R F

    1993-01-01

    where the $T_{ij}^{k\\ell}$ are essentially arbitrary scalar coefficients. Examples comprise the $q$-canonical commutation relations introduced by Greenberg, Bozejko, and Speicher, and the twisted canonical (anti-)commutation relations studied by Pusz and Woronowicz, as well as the quantum group S$_\

  14. Commutativity of missing label operators in terms of Berezin brackets

    Energy Technology Data Exchange (ETDEWEB)

    Boya, Luis J [Dpto. Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Campoamor-Stursberg, Rutwig [Dpto. GeometrIa y TopologIa, Fac. CC. Matematicas, Universidad Complutense de Madrid, Plaza de Ciencias, 3 E-28040 Madrid (Spain)], E-mail: luisjo@unizar.es, E-mail: rutwig@mat.ucm.es

    2009-06-12

    We obtain a criterion on the commutativity of polynomials in the enveloping algebra of a Lie algebra in terms of an involution condition with respect to the Berezin bracket. As an application, it is shown that the commutativity requirement of missing label operators for reduction chains in the missing label problem can be solved analytically.

  15. 75 FR 69734 - Application of Island Airlines, LLC for Commuter Air Carrier Authorization

    Science.gov (United States)

    2010-11-15

    ... Airlines, LLC for Commuter Air Carrier Authorization AGENCY: Department of Transportation. ACTION: Notice... Airlines, LLC, fit, willing, and able, and awarding it Commuter Air Carrier Authorization. DATES: Persons...

  16. 77 FR 45715 - Application of Key Lime Air Corporation for Commuter Authority

    Science.gov (United States)

    2012-08-01

    ...] Application of Key Lime Air Corporation for Commuter Authority AGENCY: Department of Transportation. ACTION... Lime Air Corporation fit, willing, and able, and awarding it a Commuter Air Carrier...

  17. Inflation on a non-commutative space–time

    Directory of Open Access Journals (Sweden)

    Xavier Calmet

    2015-07-01

    Full Text Available We study inflation on a non-commutative space–time within the framework of enveloping algebra approach which allows for a consistent formulation of general relativity and of the standard model of particle physics. We show that within this framework, the effects of the non-commutativity of spacetime are very subtle. The dominant effect comes from contributions to the process of structure formation. We describe the bound relevant to this class of non-commutative theories and derive the tightest bound to date of the value of the non-commutative scale within this framework. Assuming that inflation took place, we get a model independent bound on the scale of space–time non-commutativity of the order of 19 TeV.

  18. Inflation on a non-commutative space–time

    Energy Technology Data Exchange (ETDEWEB)

    Calmet, Xavier, E-mail: x.calmet@sussex.ac.uk; Fritz, Christopher, E-mail: c.fritz@sussex.ac.uk

    2015-07-30

    We study inflation on a non-commutative space–time within the framework of enveloping algebra approach which allows for a consistent formulation of general relativity and of the standard model of particle physics. We show that within this framework, the effects of the non-commutativity of spacetime are very subtle. The dominant effect comes from contributions to the process of structure formation. We describe the bound relevant to this class of non-commutative theories and derive the tightest bound to date of the value of the non-commutative scale within this framework. Assuming that inflation took place, we get a model independent bound on the scale of space–time non-commutativity of the order of 19 TeV.

  19. A characterization of semiprojectivity for commutative C*-algebras

    DEFF Research Database (Denmark)

    Sørensen, Adam Peder Wie; Theil, Hannes

    2012-01-01

    Given a compact metric space X, we show that the commutative C*-algebra C(X) is semiprojective if and only if X is an absolute neighbourhood retract of dimension at most 1. This confirms a conjecture of Blackadar. Generalizing to the non-unital setting, we derive a characterization...... of semiprojectivity for separable, commutative C*-algebras. As applications of our results, we prove two theorems about the structure of semiprojective commutative C*-algebras. Letting A be a commutative C*-algebra, we show firstly: If I is an ideal of A and A/I is finite-dimensional, then A is semiprojective...... if and only if I is; and secondly: A is semiprojective if and only if M2(A) is. This answers two questions about semiprojective C*-algebras in the commutative case....

  20. Perfect commuting-operator strategies for linear system games

    Science.gov (United States)

    Cleve, Richard; Liu, Li; Slofstra, William

    2017-01-01

    Linear system games are a generalization of Mermin's magic square game introduced by Cleve and Mittal. They show that perfect strategies for linear system games in the tensor-product model of entanglement correspond to finite-dimensional operator solutions of a certain set of non-commutative equations. We investigate linear system games in the commuting-operator model of entanglement, where Alice and Bob's measurement operators act on a joint Hilbert space, and Alice's operators must commute with Bob's operators. We show that perfect strategies in this model correspond to possibly infinite-dimensional operator solutions of the non-commutative equations. The proof is based around a finitely presented group associated with the linear system which arises from the non-commutative equations.

  1. Mapping burned areas and burn severity patterns across the Mediterranean region

    Science.gov (United States)

    Kalogeropoulos, Christos; Amatulli, Giuseppe; Kempeneers, Pieter; Sedano, Fernando; San Miguel-Ayanz, Jesus; Camia, Andrea

    2010-05-01

    The Mediterranean region is highly susceptible to wildfires. On average, about 60,000 fires take place in this region every year, burning on average half a million hectares of forests and natural vegetation. Wildfires cause environmental degradation and affect the lives of thousands of people in the region. In order to minimize the consequences of these catastrophic events, fire managers and national authorities need to have in their disposal accurate and updated spatial information concerning the size of the burned area as well as the burn severity patterns. Mapping burned areas and burn severity patterns is necessary to effectively support the decision-making process in what concerns strategic (long-term) planning with the definition of post-fire actions at European and national scales. Although a comprehensive archive of burnt areas exists at the European Forest Fire Information System, the analysis of the severity of the areas affected by forest fires in the region is not yet available. Fire severity is influenced by many variables, including fuel type, topography and meteorological conditions before and during the fire. The analysis of fire severity is essential to determine the socio-economic impact of forest fires, to assess fire impacts, and to determine the need of post-fire rehabilitation measures. Moreover, fire severity is linked to forest fire emissions and determines the rate of recovery of the vegetation after the fire. Satellite imagery can give important insights about the conditions of the live fuel moisture content and can be used to assess changes on vegetation structure and vitality after forest fires. Fire events occurred in Greece, Portugal and Spain during the fire season of 2009 were recorded and analyzed in a GIS environment. The Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI) and the Normalized Burn Ratio (NBR) were calculated from 8-days composites MODIS/TERRA imagery from March to October 2009. In

  2. Automated pattern recognition to support geological mapping and exploration target generation - A case study from southern Namibia

    Science.gov (United States)

    Eberle, Detlef; Hutchins, David; Das, Sonali; Majumdar, Anandamayee; Paasche, Hendrik

    2015-06-01

    This paper demonstrates a methodology for the automatic joint interpretation of high resolution airborne geophysical and space-borne remote sensing data to support geological mapping in a largely automated, fast and objective manner. At the request of the Geological Survey of Namibia (GSN), part of the Gordonia Subprovince of the Namaqua Metamorphic Belt situated in southern Namibia was selected for this study. All data - covering an area of 120 km by 100 km in size - were gridded, with a spacing of adjacent data points of only 200 m. The data points were coincident for all data sets. Published criteria were used to characterize the airborne magnetic data and to establish a set of attributes suitable for the recognition of linear features and their pattern within the study area. This multi-attribute analysis of the airborne magnetic data provided the magnetic lineament pattern of the study area. To obtain a (pseudo-) lithology map of the area, the high resolution airborne gamma-ray data were integrated with selected Landsat band data using unsupervised fuzzy partitioning clustering. The outcome of this unsupervised clustering is a classified (zonal) map which in terms of the power of spatial resolution is superior to any regional geological mapping. The classified zones are then assigned geological/geophysical parameters and attributes known from the study area, e.g. lithology, physical rock properties, age, chemical composition, geophysical field characteristics, etc. This information is obtained from the examination of archived geological reports, borehole logs, any kind of existing geological/geophysical data and maps as well as ground truth controls where deemed necessary. To obtain a confidence measure validating the unsupervised fuzzy clustering results and receive a quality criterion of the classified zones, stepwise linear discriminant analysis was chosen. Only a small percentage (8%) of the samples was misclassified by discriminant analysis when compared

  3. Mapping the Geography of Science: Distribution Patterns and Networks of Relations among Cities and Institutes

    CERN Document Server

    Leydesdorff, Loet

    2010-01-01

    Using Google Earth, Google Maps and/or network visualization programs such as Pajek, one can overlay the network of relations among addresses in scientific publications on the geographic map. We discuss the pros en cons of the various options, and provide software (freeware) for bridging existing gaps between the Science Citation Indices and Scopus, on the one side, and these various visualization tools, on the other. At the level of city names, the global map can be drawn reliably on the basis of the available address information. At the level of the names of organizations and institutes, there are problems of unification both in the ISI-databases and Scopus. Pajek enables us to combine the visualization with statistical analysis, whereas the Google Maps and its derivates provide superior tools at the Internet.

  4. New Patterns in Steady-State Chemical Kinetics: Intersections, Coincidences, Map of Events (Two-Step Mechanism

    Directory of Open Access Journals (Sweden)

    Daniel Branco Pinto

    2015-10-01

    Full Text Available New patterns of steady-state chemical kinetics for continuously stirred-tank reactors (CSTR have been found, i.e., intersections, maxima and coincidences, for two-step mechanism A↔B→C. There were found elegant analytical relationships for characteristics of these patterns (space times, values of concentrations and rates allowing kinetic parameters to be easily determined. It was demonstrated that for the pair of species involved into the irreversible reaction (B and C, the space time of their corresponding concentration dependence intersection is invariant and does not depend on the initial conditions of the system. Maps of patterns are presented for visualization of their combinations and ranking in space time, and values of concentration and rates.

  5. Patterns of accentuated grey-white differentiation on diffusion-weighted imaging or the apparent diffusion coefficient maps in comatose survivors after global brain injury

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E., E-mail: xmida@hanmail.ne [Department of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Department of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Sohn, C.-H.; Chang, K.-H. [Department of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chang, H.-W. [Departement of Radiology, Keimyung University Dongsan Medical Center, Daegu (Korea, Republic of); Lee, D.H. [Department of Radiology, Seoul Medical Center, Seoul (Korea, Republic of)

    2011-05-15

    Aim: To determine what disease entities show accentuated grey-white differentiation of the cerebral hemisphere on diffusion-weighted images (DWI) or apparent diffusion coefficient (ADC) maps, and whether there is a correlation between the different patterns and the cause of the brain injury. Methods and materials: The DWI and ADC maps of 19 patients with global brain injury were reviewed and evaluated to investigate whether there was a correlation between the different patterns seen on the DWI and ADC maps and the cause of global brain injury. The ADC values were measured for quantitative analysis. Results: There were three different patterns of ADC decrease: a predominant ADC decrease in only the cerebral cortex (n = 8; pattern I); an ADC decrease in both the cerebral cortex and white matter (WM) and a predominant decrease in the WM (n = 9; pattern II); and a predominant ADC decrease in only the WM (n = 3; pattern III). Conclusion: Pattern I is cerebral cortical injury, suggesting cortical laminar necrosis in hypoxic brain injury. Pattern II is cerebral cortical and WM injury, frequently seen in brain death, while pattern 3 is mainly WM injury, especially found in hypoglycaemic brain injury. It is likely that pattern I is decorticate injury and pattern II is decerebrate injury in hypoxic ischaemic encephalopathy.Patterns I and II are found in severe hypoxic brain injury, and pattern II is frequently shown in brain death, whereas pattern III was found in severe hypoglycaemic injury.

  6. Dynamic maps: a visual-analytic methodology for exploring spatio-temporal disease patterns

    Directory of Open Access Journals (Sweden)

    Chui Kenneth KH

    2009-12-01

    Full Text Available Abstract Background Epidemiologic studies are often confounded by the human and environmental interactions that are complex and dynamic spatio-temporal processes. Hence, it is difficult to discover nuances in the data and generate pertinent hypotheses. Dynamic mapping, a method to simultaneously visualize temporal and spatial information, was introduced to elucidate such complexities. A conceptual framework for dynamic mapping regarding principles and implementation methods was proposed. Methods The spatio-temporal dynamics of Salmonella infections for 2002 in the U.S. elderly were depicted via dynamic mapping. Hospitalization records were obtained from the Centers of Medicare and Medicaid Services. To visualize the spatial relationship, hospitalization rates were computed and superimposed onto maps of environmental exposure factors including livestock densities and ambient temperatures. To visualize the temporal relationship, the resultant maps were composed into a movie. Results The dynamic maps revealed that the Salmonella infections peaked at specific spatio-temporal loci: more clusters were observed in the summer months and higher density of such clusters in the South. The peaks were reached when the average temperatures were greater than 83.4°F (28.6°C. Although the relationship of salmonellosis rates and occurrence of temperature anomalies was non-uniform, a strong synchronization was found between high broiler chicken sales and dense clusters of cases in the summer. Conclusions Dynamic mapping is a practical visual-analytic technique for public health practitioners and has an outstanding potential in providing insights into spatio-temporal processes such as revealing outbreak origins, percolation and travelling waves of the diseases, peak timing of seasonal outbreaks, and persistence of disease clusters.

  7. Electronically commutated motors for vehicle applications

    Science.gov (United States)

    Echolds, E. F.

    1980-02-01

    Two permanent magnet electronically commutated motors for electric vehicle traction are discussed. One, based on existing technology, produces 23 kW (peak) at 26,000 rpm, and 11 kW continuous at 18,000 rpm. The motor has a conventional design: a four-pole permanent magnet rotor and a three-phase stator similar to those used on ordinary induction motors. The other, advanced technology motor, is rated at 27 kW (peak) at 14,000 rpm, and 11 kW continuous at 10,500 rpm. The machine employs a permanent magnet rotor and a novel ironless stator design in an axial air gap, homopolar configuration. Comparison of the new motors with conventional brush type machines indicates potential for substantial cost savings.

  8. The use of ultraproducts in commutative algebra

    CERN Document Server

    Schoutens, Hans

    2010-01-01

    In spite of some recent applications of ultraproducts in algebra, they remain largely unknown to commutative algebraists, in part because they do not preserve basic properties such as Noetherianity. This work wants to make a strong case against these prejudices. More precisely, it studies ultraproducts of Noetherian local rings from a purely algebraic perspective, as well as how they can be used to transfer results between the positive and zero characteristics, to derive uniform bounds, to define tight closure in characteristic zero, and to prove asymptotic versions of homological conjectures in mixed characteristic. Some of these results are obtained using variants called chromatic products, which are often even Noetherian. This book, neither assuming nor using any logical formalism, is intended for algebraists and geometers, in the hope of popularizing ultraproducts and their applications in algebra.

  9. Finite dimensional quotients of commutative operator algebras

    CERN Document Server

    Meyer, R

    1997-01-01

    The matrix normed structure of the unitization of a (non-selfadjoint) operator algebra is determined by that of the original operator algebra. This yields a classification up to completely isometric isomorphism of two-dimensional unital operator algebras. This allows to define invariant distances on the spectrum of commutative operator algebras analogous to the Caratheodory distance for complex manifolds. Moreover, unitizations of two-dimensional operator algebras with zero multiplication provide a rich class of counterexamples. Especially, several badly behaved quotients of function algebras are exhibited. Recently, Arveson has developed a model theory for d-contractions. Quotients of the operator algebra of the d-shift are much more well-behaved than quotients of function algebras. Completely isometric representations of these quotients are obtained explicitly. This provides a generalization of Nevanlinna-Pick theory. An important property of quotients of the d-shift algebra is that their quotients of finit...

  10. Commutative rings with homomorphic power functions

    Directory of Open Access Journals (Sweden)

    David E. Dobbs

    1992-01-01

    Full Text Available A (commutative ring R (with identity is called m-linear (for an integer m≥2 if (a+bm=am+bm for all a and b in R. The m-linear reduced rings are characterized, with special attention to the finite case. A structure theorem reduces the study of m-linearity to the case of prime characteristic, for which the following result establishes an analogy with finite fields. For each prime p and integer m≥2 which is not a power of p, there exists an integer s≥m such that, for each ring R of characteristic p, R is m-linear if and only if rm=rps for each r in R. Additional results and examples are given.

  11. Tensor products of commutative Banach algebras

    Directory of Open Access Journals (Sweden)

    U. B. Tewari

    1982-01-01

    Full Text Available Let A1, A2 be commutative semisimple Banach algebras and A1⊗∂A2 be their projective tensor product. We prove that, if A1⊗∂A2 is a group algebra (measure algebra of a locally compact abelian group, then so are A1 and A2. As a consequence, we prove that, if G is a locally compact abelian group and A is a comutative semi-simple Banach algebra, then the Banach algebra L1(G,A of A-valued Bochner integrable functions on G is a group algebra if and only if A is a group algebra. Furthermore, if A has the Radon-Nikodym property, then the Banach algebra M(G,A of A-valued regular Borel measures of bounded variation on G is a measure algebra only if A is a measure algebra.

  12. Electronically commutated dc motors for electric vehicles

    Science.gov (United States)

    Maslowski, E. A.

    1981-01-01

    A motor development program to explore the feasibility of electronically commutated dc motors (also known as brushless) for electric cars is described. Two different design concepts and a number of design variations based on these concepts are discussed. One design concept is based on a permanent magnet, medium speed, machine rated at 7000 to 9000 rpm, and powered via a transistor inverter power conditioner. The other concept is based on a permanent magnet, high speed, machine rated at 22,000 to 26,000 rpm, and powered via a thyristor inverter power conditioner. Test results are presented for a medium speed motor and a high speed motor each of which have been fabricated using samarium cobalt permanent magnet material.

  13. Sensing Urban Patterns with Antenna Mappings: The Case of Santiago, Chile

    Directory of Open Access Journals (Sweden)

    Eduardo Graells-Garrido

    2016-07-01

    Full Text Available Mobile data has allowed us to sense urban dynamics at scales and granularities not known before, helping urban planners to cope with urban growth. A frequently used kind of dataset are Call Detail Records (CDR, used by telecommunication operators for billing purposes. Being an already extracted and processed dataset, it is inexpensive and reliable. A common assumption with respect to geography when working with CDR data is that the position of a device is the same as the Base Transceiver Station (BTS it is connected to. Because the city is divided into a square grid, or by coverage zones approximated by Voronoi tessellations, CDR network events are assigned to corresponding areas according to BTS position. This geolocation may suffer from non negligible error in almost all cases. In this paper we propose “Antenna Virtual Placement” (AVP, a method to geolocate mobile devices according to their connections to BTS, based on decoupling antennas from its corresponding BTS according to its physical configuration (height, downtilt, and azimuth. We use AVP applied to CDR data as input for two different tasks: first, from an individual perspective, what places are meaningful for them? And second, from a global perspective, how to cluster city areas to understand land use using floating population flows? For both tasks we propose methods that complement or improve prior work in the literature. Our proposed methods are simple, yet not trivial, and work with daily CDR data from the biggest telecommunication operator in Chile. We evaluate them in Santiago, the capital of Chile, with data from working days from June 2015. We find that: (1 AVP improves city coverage of CDR data by geolocating devices to more city areas than using standard methods; (2 we find important places (home and work for a 10% of the sample using just daily information, and recreate the population distribution as well as commuting trips; (3 the daily rhythms of floating population

  14. Sensing Urban Patterns with Antenna Mappings: The Case of Santiago, Chile †

    Science.gov (United States)

    Graells-Garrido, Eduardo; Peredo, Oscar; García, José

    2016-01-01

    Mobile data has allowed us to sense urban dynamics at scales and granularities not known before, helping urban planners to cope with urban growth. A frequently used kind of dataset are Call Detail Records (CDR), used by telecommunication operators for billing purposes. Being an already extracted and processed dataset, it is inexpensive and reliable. A common assumption with respect to geography when working with CDR data is that the position of a device is the same as the Base Transceiver Station (BTS) it is connected to. Because the city is divided into a square grid, or by coverage zones approximated by Voronoi tessellations, CDR network events are assigned to corresponding areas according to BTS position. This geolocation may suffer from non negligible error in almost all cases. In this paper we propose “Antenna Virtual Placement” (AVP), a method to geolocate mobile devices according to their connections to BTS, based on decoupling antennas from its corresponding BTS according to its physical configuration (height, downtilt, and azimuth). We use AVP applied to CDR data as input for two different tasks: first, from an individual perspective, what places are meaningful for them? And second, from a global perspective, how to cluster city areas to understand land use using floating population flows? For both tasks we propose methods that complement or improve prior work in the literature. Our proposed methods are simple, yet not trivial, and work with daily CDR data from the biggest telecommunication operator in Chile. We evaluate them in Santiago, the capital of Chile, with data from working days from June 2015. We find that: (1) AVP improves city coverage of CDR data by geolocating devices to more city areas than using standard methods; (2) we find important places (home and work) for a 10% of the sample using just daily information, and recreate the population distribution as well as commuting trips; (3) the daily rhythms of floating population allow to

  15. EVALUATION OF TEMPORAL VARIATIONS IN HYDRAULIC CAPTURE DUE TO CHANGING FLOW PATTERNS USING MAPPING AND MODELING TECHNIQUES

    Energy Technology Data Exchange (ETDEWEB)

    SPILIOTOPOULOS AA; SWANSON LC; SHANNON R; TONKIN MJ

    2011-04-07

    Robust performance evaluation represents one of the most challenging aspects of groundwater pump-and-treat (P&T) remedy implementation. In most cases, the primary goal of the P&T system is hydraulic containment, and ultimately recovery, of contaminants to protect downgradient receptors. Estimating the extent of hydraulic containment is particularly challenging under changing flow patterns due to variable pumping, boundaries and/or other conditions. We present a systematic approach to estimate hydraulic containment using multiple lines of evidence based on (a) water-level mapping and (b) groundwater modeling. Capture Frequency Maps (CFMs) are developed by particle tracking on water-level maps developed for each available water level data set using universal kriging. In a similar manner, Capture Efficiency Maps (CEMs) are developed by particle tracking on water-levels calculated using a transient groundwater flow model: tracking is undertaken independently for each stress period using a very low effective porosity, depicting the 'instantaneous' fate of each particle each stress period. Although conceptually similar, the two methods differ in their underlying assumptions and their limitations: their use together identifies areas where containment may be reliable (i.e., where the methods are in agreement) and where containment is uncertain (typically, where the methods disagree). A field-scale example is presented to illustrate these concepts.

  16. Commuting behavior of western U.S. residents

    Energy Technology Data Exchange (ETDEWEB)

    Caviglia, J. [Tennessee Univ., Knoxville, TN (United States)]|[Oak Ridge National Lab., TN (United States)

    1996-06-01

    Estimation and interpretation of commutes to work has been studied extensively with respect to gender, race, and income. While the literature is extensive in these areas, there has been little research on regional differences between US states and territories. Since data which reports the commute to work is in average minutes, the distance traveled is estimated using estimates of the distance between home and work county centroids. The models differ in estimation of in-county commutes. The first assumes that the commute is equal to the radius of the county and the second estimates the commute as a weighted distance based on place location. Two data sets are compared, US National Guard data and US census data. Goal of this paper is to make conclusions about the commuting behavior of western residents through the use of these estimates, and therefore to provide a estimation method for distance commutes which can be used in further research. It is concluded that the radius method of estimation may be an over estimation, in particular in the western states. Since the non-western states are generally more homogeneously populated, this overestimation is not observed. It is recommended that the place location method be used for similar research, in particular studies dealing with western states. Suggestions are made for further research and recommendations are made for the US Army National Guard in regards to recruiting.

  17. Weakly coupled map lattice models for multicellular patterning and collective normalization of abnormal single-cell states

    Science.gov (United States)

    García-Morales, Vladimir; Manzanares, José A.; Mafe, Salvador

    2017-04-01

    We present a weakly coupled map lattice model for patterning that explores the effects exerted by weakening the local dynamic rules on model biological and artificial networks composed of two-state building blocks (cells). To this end, we use two cellular automata models based on (i) a smooth majority rule (model I) and (ii) a set of rules similar to those of Conway's Game of Life (model II). The normal and abnormal cell states evolve according to local rules that are modulated by a parameter κ . This parameter quantifies the effective weakening of the prescribed rules due to the limited coupling of each cell to its neighborhood and can be experimentally controlled by appropriate external agents. The emergent spatiotemporal maps of single-cell states should be of significance for positional information processes as well as for intercellular communication in tumorigenesis, where the collective normalization of abnormal single-cell states by a predominantly normal neighborhood may be crucial.

  18. Non-Commutative Geometry, Categories and Quantum Physics

    CERN Document Server

    Bertozzini, Paolo; Lewkeeratiyutkul, Wicharn

    2008-01-01

    After an introduction to some basic issues in non-commutative geometry (Gel'fand duality, spectral triples), we present a "panoramic view" of the status of our current research program on the use of categorical methods in the setting of A.Connes' non-commutative geometry: morphisms/categories of spectral triples, categorification of Gel'fand duality. We conclude with a summary of the expected applications of "categorical non-commutative geometry" to structural questions in relativistic quantum physics: (hyper)covariance, quantum space-time, (algebraic) quantum gravity.

  19. Non-Commutative Mechanics in Mathematical & in Condensed Matter Physics

    Directory of Open Access Journals (Sweden)

    Peter A. Horváthy

    2006-12-01

    Full Text Available Non-commutative structures were introduced, independently and around the same time, in mathematical and in condensed matter physics (see Table 1. Souriau's construction applied to the two-parameter central extension of the planar Galilei group leads to the ''exotic'' particle, which has non-commuting position coordinates. A Berry-phase argument applied to the Bloch electron yields in turn a semiclassical model that has been used to explain the anomalous/spin/optical Hall effects. The non-commutative parameter is momentum-dependent in this case, and can take the form of a monopole in momentum space.

  20. Approximating macroscopic observables in quantum spin systems with commuting matrices

    CERN Document Server

    Ogata, Yoshiko

    2011-01-01

    Macroscopic observables in a quantum spin system are given by sequences of spatial means of local elements $\\frac{1}{2n+1}\\sum_{j=-n}^n\\gamma_j(A_{i}), \\; n\\in{\\mathbb N},\\; i=1,...,m$ in a UHF algebra. One of their properties is that they commute asymptotically, as $n$ goes to infinity. It is not true that any given set of asymptotically commuting matrices can be approximated by commuting ones in the norm topology. In this paper, we show that for macroscopic observables, this is true.

  1. Exact Discrete Analogs of Canonical Commutation and Uncertainty Relations

    Directory of Open Access Journals (Sweden)

    Vasily E. Tarasov

    2016-06-01

    Full Text Available An exact discretization of the canonical commutation and corresponding uncertainty relations are suggested. We prove that the canonical commutation relations of discrete quantum mechanics, which is based on standard finite difference, holds for constant wave functions only. In this paper, we use the recently proposed exact discretization of derivatives, which is based on differences that are represented by infinite series. This new mathematical tool allows us to build sensible discrete quantum mechanics based on the suggested differences and includes the correct canonical commutation and uncertainty relations.

  2. Subgroup s-commutativity degree of finite groups

    CERN Document Server

    Otera, Daniele Ettore

    2010-01-01

    In a recent contribution, Tarnauceanu has introduced the subgroup commutativity degree of a finite group, adapting to the context of the lattice theory some ideas and some techniques, which were known by the studies of Lescot on the commutativity degree. This new notion allows us to detect how a group is far from having all subgroups which are permutable. In the present paper we investigate a probability, which generalizes the subgroup commutativity degree, and find some numerical restrictions on groups which are rich in S-permutable subgroups in the sense of Kegel.

  3. Utilization of RFID data to evaluate characteristics of private car commuters in Middle East Technical University campus

    Directory of Open Access Journals (Sweden)

    Oruç ALTINTAŞI

    2016-06-01

    Full Text Available Analyzing travel behavior of Middle East Technical University (METU campus users via traditional survey approach requires great effort. However, using Radio Frequency IDentification (RFID system installed at all the campus entry gates provided a cheaper and an effective approach to determine basic characteristics of the campus private car commuters. The RFID data combined with traveler details enabled the study of the arrival and departure car-based commute behavior of academic personnel, administrative personnel and students, separately. The results revealed that campus car-based travel demand is mainly active between 07: 00 to 22: 00. While the majority of the private car commuters arrive during 08: 00-09: 00, the evening peak is distributed over a much longer period from 15: 00 to 19: 00. Administrative personnel have sharper evening departures between 17: 00-18: 00, while academic ones show a more scattered pattern lasting longer. Car-traveler students mostly arrive later during 09: 00-10: 00 and start leaving the campus as early as 15: 00 lasting until late evenings. Stay time of vehicles on campus revealed that 43% of all trips to campus lasted less than 15 minutes, especially during morning and evening peaks, suggesting that a high number of RFID card holders pass through the campus, possibly for pick-ups or drop-offs. A small reverse commute pattern occurred due to the trips generated by family members of those living in on-campus housing units.

  4. An assessment of a collaborative mapping approach for exploring land use patterns for several European metropolises

    Science.gov (United States)

    Jokar Arsanjani, Jamal; Vaz, Eric

    2015-03-01

    Until recently, land surveys and digital interpretation of remotely sensed imagery have been used to generate land use inventories. These techniques however, are often cumbersome and costly, allocating large amounts of technical and temporal costs. The technological advances of web 2.0 have brought a wide array of technological achievements, stimulating the participatory role in collaborative and crowd sourced mapping products. This has been fostered by GPS-enabled devices, and accessible tools that enable visual interpretation of high resolution satellite images/air photos provided in collaborative mapping projects. Such technologies offer an integrative approach to geography by means of promoting public participation and allowing accurate assessment and classification of land use as well as geographical features. OpenStreetMap (OSM) has supported the evolution of such techniques, contributing to the existence of a large inventory of spatial land use information. This paper explores the introduction of this novel participatory phenomenon for land use classification in Europe's metropolitan regions. We adopt a positivistic approach to assess comparatively the accuracy of these contributions of OSM for land use classifications in seven large European metropolitan regions. Thematic accuracy and degree of completeness of OSM data was compared to available Global Monitoring for Environment and Security Urban Atlas (GMESUA) datasets for the chosen metropolises. We further extend our findings of land use within a novel framework for geography, justifying that volunteered geographic information (VGI) sources are of great benefit for land use mapping depending on location and degree of VGI dynamism and offer a great alternative to traditional mapping techniques for metropolitan regions throughout Europe. Evaluation of several land use types at the local level suggests that a number of OSM classes (such as anthropogenic land use, agricultural and some natural environment

  5. Principal component analysis vs. self-organizing maps combined with hierarchical clustering for pattern recognition in volcano seismic spectra

    Science.gov (United States)

    Unglert, K.; Radić, V.; Jellinek, A. M.

    2016-06-01

    Variations in the spectral content of volcano seismicity related to changes in volcanic activity are commonly identified manually in spectrograms. However, long time series of monitoring data at volcano observatories require tools to facilitate automated and rapid processing. Techniques such as self-organizing maps (SOM) and principal component analysis (PCA) can help to quickly and automatically identify important patterns related to impending eruptions. For the first time, we evaluate the performance of SOM and PCA on synthetic volcano seismic spectra constructed from observations during two well-studied eruptions at Klauea Volcano, Hawai'i, that include features observed in many volcanic settings. In particular, our objective is to test which of the techniques can best retrieve a set of three spectral patterns that we used to compose a synthetic spectrogram. We find that, without a priori knowledge of the given set of patterns, neither SOM nor PCA can directly recover the spectra. We thus test hierarchical clustering, a commonly used method, to investigate whether clustering in the space of the principal components and on the SOM, respectively, can retrieve the known patterns. Our clustering method applied to the SOM fails to detect the correct number and shape of the known input spectra. In contrast, clustering of the data reconstructed by the first three PCA modes reproduces these patterns and their occurrence in time more consistently. This result suggests that PCA in combination with hierarchical clustering is a powerful practical tool for automated identification of characteristic patterns in volcano seismic spectra. Our results indicate that, in contrast to PCA, common clustering algorithms may not be ideal to group patterns on the SOM and that it is crucial to evaluate the performance of these tools on a control dataset prior to their application to real data.

  6. Modeling Commute Length Choice Decisions in Dual-income Households%双职工家庭通勤出行长度选择研究

    Institute of Scientific and Technical Information of China (English)

    鲜于建川; 隽志才

    2012-01-01

    以双职工家庭中夫妇俩通勤出行长度选择为研究对象,建立双变量有序Probit模型,分析了影响通勤出行长度选择的主要因素,揭示了夫妇俩通勤出行选择之间的相互影响模式.模型结果表明年龄、性别、家庭收入、居住环境等因素对双方通勤出行选择的影响方向相同,互补效应在双方的通勤出行长度选择中占主导地位.%Commuter behaviour analysis has gained a lot of attention in the fields of transportation and land-use modelling. Since commute length reflects the physical separation between work and home, individual's commuting pattern is expected to be adjusted in response to the changes in housing or residential locations. Motivated by the importance of commuter behaviour this study intended to investigate the choices of commute trips of spouses of dual-income households. A bivariate ordered-Probit model was developed with commute length of the spouses as endogenous variables to examine the interrelationships between commute decisions of spouses. The model results provide useful insights into the effects of individual/household sociodemographics, housing and location characteristics on commute length choice. It is shown that journeys to work of the two spouses in a dual-income household appear to be complements and not substitutes. Results from this research would help for making better policies to provide mobility options and job accessibility.

  7. Techniques of low technology sampling of air pollution by metals: a comparison of concentrations and map patterns.

    Science.gov (United States)

    Lloyd, O L; Gailey, F A

    1987-07-01

    During a 17 month survey of air pollution in the town of Armadale, central Scotland, the concentrations of some metals (iron, manganese, zinc, lead, copper, chrome, nickel, cadmium, and cobalt) were measured in seven types of low technology sampler--four indigenous and three transplanted--at 47 sites. The geographical patterns of the concentrations in the samplers were compared on two types of map. For most metals, sites with high concentrations were present close to the foundry and also in the north of the town. The differences between the patterns of pollution shown by the various types of sampler probably reflected differing mechanisms for collection and different affinities for various sizes and types of metal particle.

  8. Patterns of recombination activity on mouse chromosome 11 revealed by high resolution mapping.

    Directory of Open Access Journals (Sweden)

    Timothy Billings

    Full Text Available The success of high resolution genetic mapping of disease predisposition and quantitative trait loci in humans and experimental animals depends on the positions of key crossover events around the gene of interest. In mammals, the majority of recombination occurs at highly delimited 1-2 kb long sites known as recombination hotspots, whose locations and activities are distributed unevenly along the chromosomes and are tightly regulated in a sex specific manner. The factors determining the location of hotspots started to emerge with the finding of PRDM9 as a major hotspot regulator in mammals, however, additional factors modulating hotspot activity and sex specificity are yet to be defined. To address this limitation, we have collected and mapped the locations of 4829 crossover events occurring on mouse chromosome 11 in 5858 meioses of male and female reciprocal F1 hybrids of C57BL/6J and CAST/EiJ mice. This chromosome was chosen for its medium size and high gene density and provided a comparison with our previous analysis of recombination on the longest mouse chromosome 1. Crossovers were mapped to an average resolution of 127 kb, and thirteen hotspots were mapped to <8 kb. Most crossovers occurred in a small number of the most active hotspots. Females had higher recombination rate than males as a consequence of differences in crossover interference and regional variation of sex specific rates along the chromosome. Comparison with chromosome 1 showed that recombination events tend to be positioned in similar fashion along the centromere-telomere axis but independently of the local gene density. It appears that mammalian recombination is regulated on at least three levels, chromosome-wide, regional, and at individual hotspots, and these regulation levels are influenced by sex and genetic background but not by gene content.

  9. A non-commuting twist in the partition function

    CERN Document Server

    Govindarajan, Suresh

    2012-01-01

    We compute a twisted index for an orbifold theory when the twist generating group does not commute with the orbifold group. The twisted index requires the theory to be defined on moduli spaces that are compatible with the twist. This is carried out for CHL models at special points in the moduli space where they admit dihedral symmetries. The commutator subgroup of the dihedral groups are cyclic groups that are used to construct the CHL orbifolds. The residual reflection symmetry is chosen to act as a `twist' on the partition function. The reflection symmetries do not commute with the orbifolding group and hence we refer to this as a non-commuting twist. We count the degeneracy of half-BPS states using the twisted partition function and find that the contribution comes mainly from the untwisted sector. We show that the generating function for these twisted BPS states are related to the Mathieu group M_{24}.

  10. Non-commutativity from coarse grained classical probabilities

    CERN Document Server

    Wetterich, C

    2010-01-01

    Non-commutative quantum physics at the atom scale can arise from coarse graining of a classical statistical ensemble at the Planck scale. Position and momentum of an isolated particle are classical observables which remain computable in terms of the coarse grained information. However, the commuting classical product of position and momentum observables is no longer defined in the coarse grained system, which is therefore described by incomplete statistics. The microphysical classical statistical ensemble at the Planck scale admits an alternative non-commuting product structure for position and momentum observables which is compatible with the coarse graining. Measurement correlations for isolated atoms are based on this non-commutative product structure. We present an explicit example for these ideas. It also realizes the discreteness of the spin observable within a microphysical classical statistical ensemble.

  11. 75 FR 13680 - Commutation of Sentence: Technical Change

    Science.gov (United States)

    2010-03-23

    ... commutation order. However, in 2005, the Bureau centralized its designation and sentence computation functions... economy of $100,000,000 or more; a major increase in costs or prices; or significant adverse effects on...

  12. Interactions Between Representation Ttheory, Algebraic Topology and Commutative Algebra

    CERN Document Server

    Pitsch, Wolfgang; Zarzuela, Santiago

    2016-01-01

    This book includes 33 expanded abstracts of selected talks given at the two workshops "Homological Bonds Between Commutative Algebra and Representation Theory" and "Brave New Algebra: Opening Perspectives," and the conference "Opening Perspectives in Algebra, Representations, and Topology," held at the Centre de Recerca Matemàtica (CRM) in Barcelona between January and June 2015. These activities were part of the one-semester intensive research program "Interactions Between Representation Theory, Algebraic Topology and Commutative Algebra (IRTATCA)." Most of the abstracts present preliminary versions of not-yet published results and cover a large number of topics (including commutative and non commutative algebra, algebraic topology, singularity theory, triangulated categories, representation theory) overlapping with homological methods. This comprehensive book is a valuable resource for the community of researchers interested in homological algebra in a broad sense, and those curious to learn the latest dev...

  13. Non-linear Vacuum Phenomena in Non-commutative QED

    CERN Document Server

    Alvarez-Gaumé, Luís

    2001-01-01

    We show that the classic results of Schwinger on the exact propagation of particles in the background of constant field-strengths and plane waves can be readily extended to the case of non-commutative QED. It is shown that non-perturbative effects on constant backgrounds are the same as their commutative counterparts, provided the on-shell gauge invariant dynamics is referred to a non-perturbatively related space-time frame. For the case of the plane wave background, we find evidence of the effective extended nature of non-commutative particles, producing retarded and advanced effects in scattering. Besides the known `dipolar' character of non-commutative neutral particles, we find that charged particles are also effectively extended, but they behave instead as `half-dipoles'.

  14. A note on commutators of Bochner-Riesz operator

    Institute of Scientific and Technical Information of China (English)

    LU Shanzhen; XIA Xia

    2007-01-01

    In terms of continuous decomposition and choosing an appropriate BMO function, the authors obtain a sharp necessary condition for Lp boundedness of the commutators generated by Bochner-Riesz operators below the critical index and BMO functions.

  15. Dimensional regularization and renormalization of non-commutative QFT

    CERN Document Server

    Gurau, R

    2007-01-01

    Using the recently introduced parametric representation of non-commutative quantum field theory, we implement here the dimensional regularization and renormalization of the vulcanized $\\Phi^{\\star 4}_4$ model on the Moyal space.

  16. Non-commutative covering spaces and their symmetries

    DEFF Research Database (Denmark)

    Canlubo, Clarisson

    dened and its corresponding Galois theory. Using this and basic concepts from algebraic geometryand spectral theory, we will give a full description of the general structure of non-centralcoverings. Examples of coverings of the rational and irrational non-commutative tori will alsobe studied. Using......-commutative covering space using Galois theory of Hopfalgebroids. We will look at basic properties of classical covering spaces that generalize to thenon-commutative framework. Afterwards, we will explore a series of examples. We will startwith coverings of a point and central coverings of commutative spaces and see...... how these areclosely tied up. Coupled Hopf algebras will be presented to give a general description of coveringsof a point. We will give a complete description of the geometry of the central coverings ofcommutative spaces using the coverings of a point. A topologized version of Hopf categories willbe...

  17. Exploring characteristics and motives of long distance commuter cyclists

    DEFF Research Database (Denmark)

    Hansen, Karsten Bruun; Nielsen, Thomas Alexander Sick

    2014-01-01

    , commuter cyclists (>5 km from home to work) have more mobility options, higher incomes, and a longer education than other commuter cyclists. The main motive for longer distance cycling is physical exercise, followed by reduced costs and time used for traveling. The long distance commuter cyclists surveyed...... are very positive about their commute - pointing to positive experiences, better mood, and stress relief as experiences related to their cycle trip to work. Policy support should devote attention to unlocking the potential that may be embedded in individuals combining their exercise and travel time......, budgets to promote active travel to work as well as the role of psychological benefits as a factor in promoting and sustaining cycling practices....

  18. Exploring characteristics and motives of long distance commuter cyclists

    DEFF Research Database (Denmark)

    Hansen, Karsten Bruun; Sick Nielsen, Thomas

    2014-01-01

    , commuter cyclists (45 km from home to work) have more mobility options, higher incomes, and a longer education than other commuter cyclists. The main motive for longer distance cycling is physical exercise, followed by reduced costs and time used for traveling. The long distance commuter cyclists surveyed...... are very positive about their commute - pointing to positive experiences, better mood, and stress relief as experiences related to their cycle trip to work. Policy support should devote attention to unlocking the potential that may be embedded in individuals combining their exercise and travel time......, budgets to promote active travel to work as well as the role of psychological benefits as a factor in promoting and sustaining cycling practices....

  19. On the renormalization of non-commutative field theories

    Science.gov (United States)

    Blaschke, Daniel N.; Garschall, Thomas; Gieres, François; Heindl, Franz; Schweda, Manfred; Wohlgenannt, Michael

    2013-01-01

    This paper addresses three topics concerning the quantization of non-commutative field theories (as defined in terms of the Moyal star product involving a constant tensor describing the non-commutativity of coordinates in Euclidean space). To start with, we discuss the Quantum Action Principle and provide evidence for its validity for non-commutative quantum field theories by showing that the equation of motion considered as insertion in the generating functional Z c [ j] of connected Green functions makes sense (at least at one-loop level). Second, we consider the generalization of the BPHZ renormalization scheme to non-commutative field theories and apply it to the case of a self-interacting real scalar field: Explicit computations are performed at one-loop order and the generalization to higher loops is commented upon. Finally, we discuss the renormalizability of various models for a self-interacting complex scalar field by using the approach of algebraic renormalization.

  20. COMMUTATION TIME ESTIMATOR FOR PM BLDC MOTOR TORQUE SIGNATURE ENHANCEMENT

    Directory of Open Access Journals (Sweden)

    WAEL A. SALAH

    2014-12-01

    Full Text Available This paper presents the development of the commutation time estimator (CTE for PM BLDC motor drives. The proposed scheme is aimed to enhance motor output torque by minimizing the generated torque ripples. The torque ripples originating from commutation instances cause spikes and dips in the motor output torque. The motor output torque could be enhanced by mitigating the phase current mismatch rate during phase current commutation period. This rate could be almost matched by introducing the commutation time estimator (CTE in order to control the rate of the energized phase current to be matched with the de-energized phase rate. Results obtained have validated and verified the proposed CTE effectiveness with a 50% average reduction of the generated torque ripples in PM BLDC motor.

  1. Strong Planck constraints on braneworld and non-commutative inflation

    Energy Technology Data Exchange (ETDEWEB)

    Calcagni, Gianluca [Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid (Spain); Kuroyanagi, Sachiko; Ohashi, Junko; Tsujikawa, Shinji, E-mail: calcagni@iem.cfmac.csic.es, E-mail: skuro@rs.tus.ac.jp, E-mail: j1211703@ed.tus.ac.jp, E-mail: shinji@rs.kagu.tus.ac.jp [Department of Physics, Faculty of Science, Tokyo University of Science, 1-3, Kagurazaka, Shinjuku-ku, Tokyo 162-8601 (Japan)

    2014-03-01

    We place observational likelihood constraints on braneworld and non-commutative inflation for a number of inflaton potentials, using Planck, WMAP polarization and BAO data. Both braneworld and non-commutative scenarios of the kind considered here are limited by the most recent data even more severely than standard general-relativity models. At more than 95 % confidence level, the monomial potential V(φ)∝φ{sup p} is ruled out for p ≥ 2 in the Randall-Sundrum (RS) braneworld cosmology and, for p > 0, also in the high-curvature limit of the Gauss-Bonnet (GB) braneworld and in the infrared limit of non-commutative inflation, due to a large scalar spectral index. Some parameter values for natural inflation, small-varying inflaton models and Starobinsky inflation are allowed in all scenarios, although some tuning is required for natural inflation in a non-commutative spacetime.

  2. Commutative algebra with a view toward algebraic geometry

    CERN Document Server

    Eisenbud, David

    1995-01-01

    Commutative Algebra is best understood with knowledge of the geometric ideas that have played a great role in its formation, in short, with a view towards algebraic geometry. The author presents a comprehensive view of commutative algebra, from basics, such as localization and primary decomposition, through dimension theory, differentials, homological methods, free resolutions and duality, emphasizing the origins of the ideas and their connections with other parts of mathematics. Many exercises illustrate and sharpen the theory and extended exercises give the reader an active part in complementing the material presented in the text. One novel feature is a chapter devoted to a quick but thorough treatment of Grobner basis theory and the constructive methods in commutative algebra and algebraic geometry that flow from it. Applications of the theory and even suggestions for computer algebra projects are included. This book will appeal to readers from beginners to advanced students of commutative algebra or algeb...

  3. The Relationships between Urban Form and Urban Commuting: An Empirical Study in China

    Directory of Open Access Journals (Sweden)

    Yu Song

    2017-07-01

    Full Text Available Urban sustainable development strategies are of great importance to rapidly urbanized countries such as China. One of the most challenging problems is how to coordinate urban spatial development with social efficiency and environmental protection, e.g., highly efficient low-carbon urban traffic. Despite broad research efforts with respect to the influence of urban form on travel patterns, questions persist as to the impact of compact urban form on travel distance and modes. In this study, we adopted urban form metrics to capture key dimensions of urban form with the aid of image processing and spatial analysis based on satellite images and statistical data from the cases of 35 cities. Combined with urban travel survey data, we empirically examined the relationships between urban form and travel patterns of local urban residents. The results showed that urban form and travel patterns have regionalized characteristics, e.g., the eastern cities are characterized by disperse urban development patterns and longer commuting times on average compared with western and central cities. We found that relatively smaller built-up areas, higher degrees of urban spatial agglomeration and more paved road area per person would decrease the commuting time of urban residents. We also found that the public transport choices of urban residents are positively associated with built-up areas and commuting times, which suggests the need for provision and promotion of facilities for a high-quality public transport system. The findings provide helpful suggestions for the planning of sustainable urban form and development of transportation.

  4. Mapping cycling patterns and trends using Strava Metro data in the city of Johannesburg, South Africa.

    Science.gov (United States)

    Musakwa, Walter; Selala, Kadibetso M

    2016-12-01

    Plans for smart mobility through cycling are often hampered by lack of information on cycling patterns and trends, particularly in cities of the developing world such as Johannesburg. Similarly, traditional methods of data collection such as bicycle counts are often expensive, cover a limited spatial extent and not up-to-date. Consequently, the dataset presented in this paper illustrates the spatial and temporal coverage of cycling patterns and trends in Johannesburg for the year 2014 derived from the geolocation based mobile application Strava. To the best knowledge of the authors, there is little or no comprehensive dataset that describes cycling patterns in Johannesburg. Perhaps this dataset is a tool that will support evidence based transportation planning and smart mobility.

  5. Mapping cycling patterns and trends using Strava Metro data in the city of Johannesburg, South Africa

    Directory of Open Access Journals (Sweden)

    Walter Musakwa

    2016-12-01

    Full Text Available Plans for smart mobility through cycling are often hampered by lack of information on cycling patterns and trends, particularly in cities of the developing world such as Johannesburg. Similarly, traditional methods of data collection such as bicycle counts are often expensive, cover a limited spatial extent and not up-to-date. Consequently, the dataset presented in this paper illustrates the spatial and temporal coverage of cycling patterns and trends in Johannesburg for the year 2014 derived from the geolocation based mobile application Strava. To the best knowledge of the authors, there is little or no comprehensive dataset that describes cycling patterns in Johannesburg. Perhaps this dataset is a tool that will support evidence based transportation planning and smart mobility.

  6. The University Workers' Willingness to pay for Commuting

    OpenAIRE

    Russo, G.; Ommeren, van, Jan-Kees; Rietveld, P.

    2010-01-01

    This discussion paper led to a publication in Transportation , 2012, 39(6), 1121-1132. Using a dynamic approach, employing data on job mobility, we demonstrate that university workers' marginal willingness to pay for reducing commuting distance is about euro 0.25 per kilometre travelled. This corresponds to a marginal willingness to pay for reducing commuting time of about 75% of the net average hourly wage. For females, the willingness to pay is substantially higher than for males. It is als...

  7. Quantum walled Brauer algebra: commuting families, Baxterization, and representations

    Science.gov (United States)

    Semikhatov, A. M.; Tipunin, I. Yu

    2017-02-01

    For the quantum walled Brauer algebra, we construct its Specht modules and (for generic parameters of the algebra) seminormal modules. The latter construction yields the spectrum of a commuting family of Jucys-Murphy elements. We also propose a Baxterization prescription; it involves representing the quantum walled Brauer algebra in terms of morphisms in a braided monoidal category and introducing parameters into these morphisms, which allows constructing a ‘universal transfer matrix’ that generates commuting elements of the algebra.

  8. Physical activity during leisure and commuting in Tianjin, China.

    OpenAIRE

    2002-01-01

    OBJECTIVE: To investigate physical activity during leisure time and commuting among persons aged 15-69 years in the urban population of Tianjin, China, and to assess its associations with demographic and health-related characteristics. METHODS: In 1996 a cross-sectional survey of 2002 males and 1974 females provided information on physical activity during leisure time and commuting and on demographics and health behaviours. FINDINGS: No leisure-time physical activity was engaged in by 67% of ...

  9. The commutants of analytic Toeplitz operators for several complex variables

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    It is proved that if  is a nonconstant bounded analytic function on the unit ball B n and continuous on S n in C n , and ψ is a bounded measurable function on S n such that T * and T ψ commute, then ψ is the boundary value of an analytic function on B n . In addition, the commutants of two Toeplitz operators are also discussed.

  10. Product and Commutativity of kth-Order Slant Toeplitz Operators

    Directory of Open Access Journals (Sweden)

    Chaomei Liu

    2013-01-01

    Full Text Available The commutativity of kth-order slant Toeplitz operators with harmonic polynomial symbols, analytic symbols, and coanalytic symbols is discussed. We show that, on the Lebesgue space and Bergman space, necessary and sufficient conditions for the commutativity of kth-order slant Toeplitz operators are that their symbol functions are linearly dependent. Also, we study the product of two kth-order slant Toeplitz operators and give some necessary and sufficient conditions.

  11. An improved 4-step commutation method application for matrix converter

    DEFF Research Database (Denmark)

    Guo, Yu; Guo, Yougui; Deng, Wenlang

    2014-01-01

    A novel four-step commutation method is proposed for matrix converter cell, 3 phase inputs to 1 phase output in this paper, which is obtained on the analysis of published commutation methods for matrix converter. The first and fourth step can be shorter than the second or third one. The discussed...... method here is implemented by programming in VHDL language. Finally, the novel method in this paper is verified by experiments....

  12. On the role of the commutator algebra for nonlinear supersymmetry

    CERN Document Server

    Shima, Kazunari

    2016-01-01

    We discuss the closure of commutator algebra for general functionals in terms of Nambu-Goldstone fermions and their derivative terms under nonlinear supersymmetry (NLSUSY) both in flat spacetime and in curved spacetime. We show that the variations of the general functionals (uniquely) determine the general structure of linear supermutiplets with general auxiliary fields for arbitrary $N$ SUSY, where the closure of the commutator algebra for NLSUSY plays a crucial role.

  13. Heat flow patterns of the North American continent: A discussion of the DNAG Geothermal Map of North America

    Energy Technology Data Exchange (ETDEWEB)

    Blackwell, David D.; Steele, John L.; Carter, Larry C.

    1990-01-01

    The large and small-scale geothermal features of the North American continent and surrounding ocean areas illustrated on the new 1:5,000,000 DNAG Geothermal Map of North America are summarized. Sources for the data included on the map are given. The types of data included are heat flow sites coded by value, contours of heat flow with a color fill, areas of major groundwater effects on regional heat flow, the top-of-geopressure in the Gulf Coast region, temperature on the Dakota aquifer in the midcontinent, location of major hot springs and geothermal systems, and major center of Quaternary and Holocene volcanism. The large scale heat flow pattern that is well known for the conterminous United States and Canada of normal heat flow east of the Cordillera and generally high heat flow west of the front of the Cordillera dominates the continental portion of the map. However, details of the heat flow variations are also seen and are discussed briefly in this and the accompanying papers.

  14. Spatial and temporal patterns of chronic wasting disease: fine-scale mapping of a wildlife epidemic in Wisconsin.

    Science.gov (United States)

    Osnas, Erik E; Heisey, Dennis M; Rolley, Robert E; Samuel, Michael D

    2009-07-01

    Emerging infectious diseases threaten wildlife populations and human health. Understanding the spatial distributions of these new diseases is important for disease management and policy makers; however, the data are complicated by heterogeneities across host classes, sampling variance, sampling biases, and the space-time epidemic process. Ignoring these issues can lead to false conclusions or obscure important patterns in the data, such as spatial variation in disease prevalence. Here, we applied hierarchical Bayesian disease mapping methods to account for risk factors and to estimate spatial and temporal patterns of infection by chronic wasting disease (CWD) in white-tailed deer (Odocoileus virginianus) of Wisconsin, U.S.A. We found significant heterogeneities for infection due to age, sex, and spatial location. Infection probability increased with age for all young deer, increased with age faster for young males, and then declined for some older animals, as expected from disease-associated mortality and age-related changes in infection risk. We found that disease prevalence was clustered in a central location, as expected under a simple spatial epidemic process where disease prevalence should increase with time and expand spatially. However, we could not detect any consistent temporal or spatiotemporal trends in CWD prevalence. Estimates of the temporal trend indicated that prevalence may have decreased or increased with nearly equal posterior probability, and the model without temporal or spatiotemporal effects was nearly equivalent to models with these effects based on deviance information criteria. For maximum interpretability of the role of location as a disease risk factor, we used the technique of direct standardization for prevalence mapping, which we develop and describe. These mapping results allow disease management actions to be employed with reference to the estimated spatial distribution of the disease and to those host classes most at risk. Future

  15. Spatial and temporal patterns of chronic wasting disease: Fine-scale mapping of a wildlife epidemic in Wisconsin

    Science.gov (United States)

    Osnas, E.E.; Heisey, D.M.; Rolley, R.E.; Samuel, M.D.

    2009-01-01

    Emerging infectious diseases threaten wildlife populations and human health. Understanding the spatial distributions of these new diseases is important for disease management and policy makers; however, the data are complicated by heterogeneities across host classes, sampling variance, sampling biases, and the space-time epidemic process. Ignoring these issues can lead to false conclusions or obscure important patterns in the data, such as spatial variation in disease prevalence. Here, we applied hierarchical Bayesian disease mapping methods to account for risk factors and to estimate spatial and temporal patterns of infection by chronic wasting disease (CWD) in white-tailed deer (Odocoileus virginianus) of Wisconsin, USA. We found significant heterogeneities for infection due to age, sex, and spatial location. Infection probability increased with age for all young deer, increased with age faster for young males, and then declined for some older animals, as expected from disease-associated mortality and age-related changes in infection risk. We found that disease prevalence was clustered in a central location, as expected under a simple spatial epidemic process where disease prevalence should increase with time and expand spatially. However, we could not detect any consistent temporal or spatiotemporal trends in CWD prevalence. Estimates of the temporal trend indicated that prevalence may have decreased or increased with nearly equal posterior probability, and the model without temporal or spatiotemporal effects was nearly equivalent to models with these effects based on deviance information criteria. For maximum interpretability of the role of location as a disease risk factor, we used the technique of direct standardization for prevalence mapping, which we develop and describe. These mapping results allow disease management actions to be employed with reference to the estimated spatial distribution of the disease and to those host classes most at risk. Future

  16. Mapping eco-environmental vulnerability patterns: An assessment framework based on remote sensing, GIS, and AHP

    Science.gov (United States)

    Anh, N. K.; Liou, Y. A.; Li, M. H.

    2016-12-01

    The motivation for this study is assessment of the eco-environment vulnerability based on four independent determinants: hydro-meteorology, topography, land resources, and human activities. An assessment framework is proposed to assess the vulnerable eco-environment by using 16 variables with 6 of them constructed from Landsat 8 satellite images. The remaining variables were extracted from digital maps. Each variable was evaluated and spatially mapped with the aid of an analytical hierarchy process (AHP) and geographical information system (GIS). The Thua Thien - Hue Province that has been experiencing natural disasters and urbanization in the recent decades is selected as our study area. An eco-environmental vulnerability map is assorted into six vulnerable levels consisting of potential, slight, light, medium, heavy, and very heavy vulnerabilities, representing 14%, 27%, 17%, 26%, 13%, 3% of the study area, respectively. It is found that heavy and very heavy vulnerable areas appear mainly in the low and medium lands with high intensification of social-economic activities and often suffer from flooding. Tiny percentages of medium and heavy vulnerable levels occur in high land areas probably caused by agricultural practices in highlands, slash and burn cultivation and removal of natural forests with new plantation forests and these regions are usually influenced by landslides, flash flooding. Based on our results, three ecological zones requiring different development and protection solutions are proposed to restore local eco-environment toward sustainable development. Our findings support the idea that eco-environmental vulnerability is driven by anthropogenic processes and enhanced by natural disaster in the Thua Thien-Hue Province.

  17. Mapping Beliefs about Teaching to Patterns of Instruction within Science, Technology, Engineering, and Mathematics

    Science.gov (United States)

    Allendoerfer, Cheryl; Wilson, Denise; Kim, Mee Joo; Burpee, Elizabeth

    2014-01-01

    In this paper, we identify beliefs about teaching and patterns of instruction valued and emphasized by science, technology, engineering, and mathematics faculty in higher education in the USA. Drawing on the notion that effective teaching is student-centered rather than teacher-centered and must include a balance of knowledge-, learner-,…

  18. Attenuation of pattern recognition receptor signaling is mediated by a MAP kinase kinase kinase

    NARCIS (Netherlands)

    Mithoe, S.C.; Ludwig, C.; Pel, M.J.C.; Cucinotta, M.; Casartelli, A.; Mbengue, M.; Sklenar, J.; Derbyshire, P.; Robatzek, S.; Pieterse, C.M.J.; Aebersold, R.; Menke, F.L.H.

    2016-01-01

    Pattern recognition receptors (PRRs) play a key role in plant and animal innate immunity. PRR binding of their cognate ligand triggers a signaling network and activates an immune response. Activation of PRR signaling must be controlled prior to ligand binding to prevent spurious signaling and immune

  19. Map misclassifications can cause large errors in landscape pattern indices: examples from habitat fragmentation.

    Science.gov (United States)

    William T. Langford; Sarah E. Gergel; Thomas G. Dietterich; Warren. Cohen

    2006-01-01

    Although habitat fragmentation is one of the greatest threats to biodiversity worldwide, virtually no attention has been paid to the quantification of error in fragmentation statistics. Landscape pattern indices (LPIs), such as mean patch size and number of patches, are routinely used to quantify fragmentation and are often calculated using remote sensing imagery that...

  20. Grand Unification in Non-Commutative Geometry

    CERN Document Server

    Chamseddine, A H; Fröhlich, J

    1993-01-01

    The formalism of non-commutative geometry of A. Connes is used to construct models in particle physics. The physical space-time is taken to be a product of a continuous four-manifold by a discrete set of points. The treatment of Connes is modified in such a way that the basic algebra is defined over the space of matrices, and the breaking mechanism is planted in the Dirac operator. This mechanism is then applied to three examples. In the first example the discrete space consists of two points, and the two algebras are taken respectively to be those of $2\\times 2$ and $1\\times 1$ matrices. With the Dirac operator containing the vacuum breaking $SU(2)\\times U(1)$ to $U(1)$, the model is shown to correspond to the standard model. In the second example the discrete space has three points, two of the algebras are identical and consist of $5\\times 5$ complex matrices, and the third algebra consists of functions. With an appropriate Dirac operator this model is almost identical to the minimal $SU(5)$ model of Georgi...

  1. SOM-based Pattern Generator: Pattern Generation Based on the Backward Projection in a Self-Organizing Map and Its Applications

    Science.gov (United States)

    Wakuya, Hiroshi; Ishiguma, Takahiro

    A major feature of the self-organizing map (SOM) is a topology-preserving projection from the input layer to the competitive layer, and it has been used mainly as an analytical tool for discovering underlying rules in the given data set. Even though recent splendid progress in this area, there are few novel ideas to break such a conventional style. On the contrary, based on its distinctive nature, a new method for generating patterns through backward projection from the competitive layer to the input layer is proposed recently. Moreover, a promising technology for producing animation as a series of backward-projected patterns along with any pathways on the competitive layer is presented. Then, in order to carry out further considerations, some computer simulations with a variety of posed stick figures are tried in this paper. After training, four kinds of pathways, which correspond to different movements such as dancing, exercising and walking, are prepared. Though some of them does not contain any training samples, all of them worked well as we have intended in advance. As a result, it is found that the proposed method shows good performance and it is also confirmed its effectiveness.

  2. The Identity Mapping Project: Demographic differences in patterns of distributed identity.

    Science.gov (United States)

    Gilbert, Richard L; Dionisio, John David N; Forney, Andrew; Dorin, Philip

    2015-01-01

    The advent of cloud computing and a multi-platform digital environment is giving rise to a new phase of human identity called "The Distributed Self." In this conception, aspects of the self are distributed into a variety of 2D and 3D digital personas with the capacity to reflect any number of combinations of now malleable personality traits. In this way, the source of human identity remains internal and embodied, but the expression or enactment of the self becomes increasingly external, disembodied, and distributed on demand. The Identity Mapping Project (IMP) is an interdisciplinary collaboration between psychology and computer Science designed to empirically investigate the development of distributed forms of identity. Methodologically, it collects a large database of "identity maps" - computerized graphical representations of how active someone is online and how their identity is expressed and distributed across 7 core digital domains: email, blogs/personal websites, social networks, online forums, online dating sites, character based digital games, and virtual worlds. The current paper reports on gender and age differences in online identity based on an initial database of distributed identity profiles.

  3. A filtering method to reveal crystalline patterns from atom probe microscopy desorption maps.

    Science.gov (United States)

    Yao, Lan

    2016-01-01

    A filtering method to reveal the crystallographic information present in Atom Probe Microscopy (APM) data is presented. The method filters atoms based on the time difference between their evaporation and the evaporation of the previous atom. Since this time difference correlates with the location and the local structure of the evaporating atoms on the surface, it can be used to reveal any crystallographic information contained within APM data. The demonstration of this method is illustrated on: •A pure Al specimen for which crystallographic poles are clearly visible on the desorption patterns easily indexed.•Three Fe-15at.% Cr datasets where crystallographic patterns are less obvious and require this filtering method.

  4. Changes in Active Commuting to School in Czech Adolescents in Different Types of Built Environment across a 10-Year Period

    Directory of Open Access Journals (Sweden)

    Jan Dygrýn

    2015-10-01

    Full Text Available Active commuting (AC to school represents a great opportunity to incorporate walking or cycling into adolescents’ everyday routine. The objective of the study was to describe changes in AC in Czech adolescents across a 10-year period in different built environments. Data from the 2001 and 2011 Czech Census of Population and Housing were used to examine the mode of transportation taken to school in 6236 adolescents. Changes in AC over time were analyzed for low and high walkable areas separately in two Czech regional cities, Olomouc and Hradec Králové. Between 2001 and 2011, the proportion of adolescents actively commuting to school decreased by 47%, from an absolute rate of 49.1% to 26%. The proportion of active commuters fell in low walkable areas by 61% and in high walkable areas by 39%. The results indicated that adolescents in 2011 were 2.7 times less (OR = 0.365, p < 0.001 likely to actively commute than in 2001. The AC behavior in Czech adolescents has a negative tendency to replicate travel-to-school patterns in adolescents previously described in more developed countries. The findings might serve as a recommendation for municipal policy.

  5. Changes in Active Commuting to School in Czech Adolescents in Different Types of Built Environment across a 10-Year Period.

    Science.gov (United States)

    Dygrýn, Jan; Mitáš, Josef; Gába, Aleš; Rubín, Lukáš; Frömel, Karel

    2015-10-16

    Active commuting (AC) to school represents a great opportunity to incorporate walking or cycling into adolescents' everyday routine. The objective of the study was to describe changes in AC in Czech adolescents across a 10-year period in different built environments. Data from the 2001 and 2011 Czech Census of Population and Housing were used to examine the mode of transportation taken to school in 6236 adolescents. Changes in AC over time were analyzed for low and high walkable areas separately in two Czech regional cities, Olomouc and Hradec Králové. Between 2001 and 2011, the proportion of adolescents actively commuting to school decreased by 47%, from an absolute rate of 49.1% to 26%. The proportion of active commuters fell in low walkable areas by 61% and in high walkable areas by 39%. The results indicated that adolescents in 2011 were 2.7 times less (OR = 0.365, p < 0.001) likely to actively commute than in 2001. The AC behavior in Czech adolescents has a negative tendency to replicate travel-to-school patterns in adolescents previously described in more developed countries. The findings might serve as a recommendation for municipal policy.

  6. The spatial distribution of commuting CO2 emissions and the influential factors: A case study in Xi'an, China

    Directory of Open Access Journals (Sweden)

    Yuan-Yuan Liu

    2015-03-01

    Full Text Available As the transport sector is a major source of greenhouse gas emissions, the effect of urbanization on transport CO2 emissions in developing cities has become a key issue under global climate change. Examining the case of Xi'an, this paper aims to explore the spatial distribution of commuting CO2 emissions and influencing factors in the new, urban industry zones and city centers considering Xi'an's transition from a monocentric to a polycentric city in the process of urbanization. Based on household survey data from 1501 respondents, there are obvious differences in commuting CO2 emissions between new industry zones and city centers: City centers feature lower household emissions of 2.86 kg CO2 per week, whereas new industry zones generally have higher household emissions of 3.20 kg CO2 per week. Contrary to previous research results, not all new industry zones have high levels of CO2 emissions; with the rapid development of various types of industries, even a minimum level of household emissions of 2.53 kg CO2 per week is possible. The uneven distribution of commuting CO2 emissions is not uniformly affected by spatial parameters such as job–housing balance, residential density, employment density, and land use diversity. Optimum combination of the spatial parameters and travel pattern along with corresponding transport infrastructure construction may be an appropriate path to reduction and control of emissions from commuting.

  7. Trivial Low Energy States for Commuting Hamiltonians, and the Quantum PCP Conjecture

    CERN Document Server

    Hastings, M B

    2012-01-01

    We consider whether or not Hamiltonians which are sums of commuting projectors have "trivial" ground states which can be constructed by a local quantum circuit of bounded depth and range acting on a product state. While the toric code only has nontrivial ground states, commuting projector Hamiltonians which are sums of two-body interactions have trivial ground states. We define an "interaction complex" for a Hamiltonian, generalizing the interaction graph, and we show that if this complex can be continuously mapped to a 1-complex using a map with bounded diameter of pre-images then the Hamiltonian has a trivial ground state assuming one technical condition on the Hamiltonian (this condition holds for all stabilizer Hamiltonians, and we also prove the result for all Hamiltonians under an assumption on the 1-complex). While this includes cases considered by Ref., it also includes other Hamiltonians whose interaction complexes cannot be coarse-grained into the case of Ref. One motivation for this is the quantum ...

  8. Patterns of upper layer circulation variability in the South China Sea from satellite altimetry using the self-organizing map

    Institute of Scientific and Technical Information of China (English)

    LIU Yonggang; WEISBERG Robert H; YUAN Yaochu

    2008-01-01

    Patterns of the South China Sea (SCS) circulation variability are extracted from merged satellite altimetry data from October 1992 through August 2004 by using the self-organizing map (SOM). The annual cycle, seasonal and inter-annual variations of the SCS surface circulation are identified through the evolution of the characteristic circulation patterns. The annual cycle of the SCS gener- al circulation patterns is described as a change between two opposite basin-scale SW-NE oriented gyres embedded with eddies: low sea surface height anomaly (SSHA) (cyclonic) in winter and high SSHA (anticyclonic) in summer half year. The transition starts from July--August (January--February) with a high (low) SSHA tongue east of Vietnam around 12°~14° N, which de- velopa into a big anticyclonic (cyclonic) gyre while moving eastward to the deep basin. During the transitions, a dipole structure, cyclonic (anticyclonic) in the north and anticyclonic (cyclonic) in the south, may be formed southeast off Vietnam with a strong zonal jet around 10°~12° N. The seasonal variation is modulated by the interannual variations. Besides the strong 1997/1998 e- vent in response to the peak Pacific El Nino in 1997, the overall SCS sea level is found to have a significant rise during 1999~ 2001, however, in summer 2004 the overall SCS sea level is lower and the basin-wide anticyclonic gyre becomes weaker than the other years.

  9. Oscillatory neurocomputing with ring attractors: a network architecture for mapping locations in space onto patterns of neural synchrony.

    Science.gov (United States)

    Blair, Hugh T; Wu, Allan; Cong, Jason

    2014-02-01

    Theories of neural coding seek to explain how states of the world are mapped onto states of the brain. Here, we compare how an animal's location in space can be encoded by two different kinds of brain states: population vectors stored by patterns of neural firing rates, versus synchronization vectors stored by patterns of synchrony among neural oscillators. It has previously been shown that a population code stored by spatially tuned 'grid cells' can exhibit desirable properties such as high storage capacity and strong fault tolerance; here it is shown that similar properties are attainable with a synchronization code stored by rhythmically bursting 'theta cells' that lack spatial tuning. Simulations of a ring attractor network composed from theta cells suggest how a synchronization code might be implemented using fewer neurons and synapses than a population code with similar storage capacity. It is conjectured that reciprocal connections between grid and theta cells might control phase noise to correct two kinds of errors that can arise in the code: path integration and teleportation errors. Based upon these analyses, it is proposed that a primary function of spatially tuned neurons might be to couple the phases of neural oscillators in a manner that allows them to encode spatial locations as patterns of neural synchrony.

  10. Cleavage pattern and fate map of the mesentoblast, 4d, in the gastropod Crepidula: a hallmark of spiralian development

    Directory of Open Access Journals (Sweden)

    Lyons Deirdre C

    2012-09-01

    Full Text Available Abstract Background Animals with a spiral cleavage program, such as mollusks and annelids, make up the majority of the superphylum Lophotrochozoa. The great diversity of larval and adult body plans in this group emerges from this highly conserved developmental program. The 4d micromere is one of the most conserved aspects of spiralian development. Unlike the preceding pattern of spiral divisions, cleavages within the 4d teloblastic sublineages are bilateral, representing a critical transition towards constructing the bilaterian body plan. These cells give rise to the visceral mesoderm in virtually all spiralians examined and in many species they also contribute to the endodermal intestine. Hence, the 4d lineage is an ideal one for studying the evolution and diversification of the bipotential endomesodermal germ layer in protostomes at the level of individual cells. Little is known of how division patterns are controlled or how mesodermal and endodermal sublineages diverge in spiralians. Detailed modern fate maps for 4d exist in only a few species of clitellate annelids, specifically in glossiphoniid leeches and the sludge worm Tubifex. We investigated the 4d lineage in the gastropod Crepidula fornicata, an established model system for spiralian biology, and in a closely related direct-developing species, C. convexa. Results High-resolution cell lineage tracing techniques were used to study the 4d lineage of C. fornicata and C. convexa. We present a new nomenclature to name the progeny of 4d, and report the fate map for the sublineages up through the birth of the first five pairs of teloblast daughter cells (when 28 cells are present in the 4d sublineage, and describe each clone’s behavior during gastrulation and later stages as these undergo differentiation. We identify the precise origin of the intestine, two cells of the larval kidney complex, the larval retractor muscles and the presumptive germ cells, among others. Other tissues that arise

  11. The active commuting route environment scale (ACRES: development and evaluation

    Directory of Open Access Journals (Sweden)

    Stigell Erik

    2010-07-01

    Full Text Available Abstract Background Route environments can be a potentially important factor in influencing people's behaviours in relation to active commuting. To better understand these possible relationships, assessments of route environments are needed. We therefore developed a scale; the Active Commuting Route Environment Scale (ACRES, for the assessment of bicyclists' and pedestrians' perceptions of their commuting route environments. Here we will report on the development and the results of validity and reliability assessments thereof. Methods Active commuters (n = 54 were recruited when they bicycled in Stockholm, Sweden. Traffic planning and environmental experts from the Municipality of Stockholm were assembled to form an expert panel (n = 24. The active commuters responded to the scale on two occasions, and the expert panel responded to it once. To test criterion-related validity, differences in ratings of the inner urban and suburban environments of Greater Stockholm were compared between the experts and the commuters. Furthermore, four items were compared with existing objective measures. Test-retest reproducibility was assessed with three types of analysis: order effect, typical error and intraclass correlation. Results There was a concordance in sizes and directions of differences in ratings of inner urban and suburban environments between the experts and the commuters. Furthermore, both groups' ratings were in line with existing objectively measured differences between the two environmental settings. Order effects between test and retest were observed in 6 of 36 items. The typical errors ranged from 0.93 to 2.54, and the intraclass correlation coefficients ranged from 'moderate' (0.42 to 'almost perfect' (0.87. Conclusions The ACRES was characterized by considerable criterion-related validity and reasonable test-retest reproducibility.

  12. Sphingoid Base Metabolism in Yeast: Mapping Gene Expression Patterns Into Qualitative Metabolite Time Course Predictions

    OpenAIRE

    Tomas Radivoyevitch

    2001-01-01

    Can qualitative metabolite time course predictions be inferred from measured mRNA expression patterns? Speaking against this possibility is the large number of ‘decoupling’ control points that lie between these variables, i.e. translation, protein degradation, enzyme inhibition and enzyme activation. Speaking for it is the notion that these control points might be coordinately regulated such that action exerted on the mRNA level is informative of action exerted on the protein and me...

  13. The non-commutative Weil algebra

    OpenAIRE

    1999-01-01

    Let G be a connected Lie group with Lie algebra g. The Duflo map is a vector space isomorphism between the symmetric algebra S(g) and the universal enveloping algebra U(g) which, as proved by Duflo, restricts to a ring isomorphism from invariant polynomials onto the center of the universal enveloping algebra. The Duflo map extends to a linear map from compactly supported distributions on the Lie algebra g to compactly supported distributions on the Lie group G, which is a ring homomorphism fo...

  14. Monthly Hydrological Model Evaluation through Mapping the Hydrological Pattern to Information Space

    Science.gov (United States)

    Pan, B.; Cong, Z.

    2014-12-01

    Conceptual and stochastic monthly hydrological models have been widely used for climatic change impact exploration and long-range stream flow forecast. With disparate philosophies and different but insufficient inputs, most of the existing models are capable of generating satisfying outputs, which reveals a relatively robust idiosyncrasy of hydrological pattern over monthly time scale. This research uses the epistemic-aleatory uncertainties evaluation framework to examine the information source sink terms and flows of 6 conceptual monthly water balance models and a seasonal autoregressive stochastic hydrologic model over 19 basins in Jiangxi Province, China and the experiment basins of MOPEX project. By using the stream technique of Lisp, we constructed two programming paradigms into which the hydrological models mentioned above could be fitted. We focus on detecting and explaining the best achievable predictive performances and data-revealed insufficient of the models in each paradigm, especially the hydrological meaning of the iteration variables in these models. Finally, we make an attempt to compare and connect these two paradigms against the backdrop of algorithmic information theory to help us form a better understanding of monthly hydrological pattern.

  15. Mapping Activity Patterns to Quantify Risk of Violent Assault in Urban Environments.

    Science.gov (United States)

    Wiebe, Douglas J; Richmond, Therese S; Guo, Wensheng; Allison, Paul D; Hollander, Judd E; Nance, Michael L; Branas, Charles C

    2016-01-01

    We collected detailed activity paths of urban youth to investigate the dynamic interplay between their lived experiences, time spent in different environments, and risk of violent assault. We mapped activity paths of 10- to 24-year-olds, including 143 assault patients shot with a firearm, 206 assault patients injured with other types of weapons, and 283 community controls, creating a step-by-step mapped record of how, when, where, and with whom they spent time over a full day from waking up until going to bed or being assaulted. Case-control analyses compared cases with time-matched controls to identify risk factors for assault. Case-crossover analyses compared cases at the time of assault with themselves earlier in the day to investigate whether exposure increases acted to the trigger assault. Gunshot assault risks included being alone (odds ratio [OR] = 1.6, 95% confidence interval [CI] = 1.3, 1.9) and were lower in areas with high neighbor connectedness (OR = 0.7, 95% CI = 0.6, 0.8). Acquiring a gun (OR = 1.4, 95% CI = 1.1, 1.6) and entering areas with more vacancy, violence, and vandalism (OR = 1.7, 95% CI = 1.1, 2.7) appeared to trigger the risk of getting shot shortly thereafter. Nongunshot assault risks included being in areas with recreation centers (OR = 1.2, 95% CI = 1.1, 1.4). Entering an area with higher truancy (OR = 1.6, 95% CI = 1.1, 2.5) and more vacancy, violence, and vandalism appeared to trigger the risk of nongunshot assault. Risks varied by age group. We achieved a large-scale study of the activities of many boys, adolescents, and young men that systematically documented their experiences and empirically quantified risks for violence. Working at a temporal and spatial scale that is relevant to the dynamics of this phenomenon gave novel insights into triggers for violent assault.

  16. Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping

    Science.gov (United States)

    Hart, Kristen M.; Zawada, David G.; Fujisaki, Ikuko; Lidz, Barbara H.

    2010-01-01

    The loggerhead sea turtle Caretta caretta faces declining nest numbers and bycatches from commercial longline fishing in the southeastern USA. Understanding spatial and temporal habitat-use patterns of these turtles, especially reproductive females in the neritic zone, is critical for guiding management decisions. To assess marine turtle habitat use within the Dry Tortugas National Park (DRTO), we used satellite telemetry to identify core-use areas for 7 loggerhead females inter-nesting and tracked in 2008 and 2009. This effort represents the first tracking of DRTO loggerheads, a distinct subpopulation that is 1 of 7 recently proposed for upgrading from threatened to endangered under the US Endangered Species Act. We also used a rapid, high-resolution, digital imaging system to map benthic habitats in turtle core-use areas (i.e. 50% kernel density zones). Loggerhead females were seasonal residents of DRTO for 19 to 51 d, and individual inter-nesting habitats were located within 1.9 km (2008) and 2.3 km (2009) of the nesting beach and tagging site. The core area common to all tagged turtles was 4.2 km2 in size and spanned a depth range of 7.6 to 11.5 m. Mapping results revealed the diversity and distributions of benthic cover available in the core-use area, as well as a heavily used corridor to/from the nesting beach. This combined tagging-mapping approach shows potential for planning and improving the effectiveness of marine protected areas and for developing spatially explicit conservation plans.

  17. Evaluating and Mapping of Spatial Air Ion Quality Patterns in a Residential Garden Using a Geostatistic Method

    Directory of Open Access Journals (Sweden)

    Wen-Huang Lin

    2011-06-01

    Full Text Available Negative air ions (NAI produce biochemical reactions that increase the levels of the mood chemical serotonin in the environment. Moreover, they benefit both the psychological well being and the human body’s physiological condition. The aim of this research was to estimate and measure the spatial distributions of negative and positive air ions in a residential garden in central Taiwan. Negative and positive air ions were measured at thirty monitoring locations in the study garden from July 2009 to June 2010. Moreover, Kriging was applied to estimate the spatial distribution of negative and positive air ions, as well as the air ion index in the study area. The measurement results showed that the numbers of NAI and PAI differed greatly during the four seasons, the highest and the lowest negative and positive air ion concentrations were found in the summer and winter, respectively. Moreover, temperature was positively affected negative air ions concentration. No matter what temperature is, the ranges of variogram in NAI/PAI were similar during four seasons. It indicated that spatial patterns of NAI/PAI were independent of the seasons and depended on garden elements and configuration, thus the NAP/PAI was a good estimate of the air quality regarding air ions. Kriging maps depicted that the highest negative and positive air ion concentration was next to the waterfall, whereas the lowest air ions areas were next to the exits of the garden. The results reveal that waterscapes are a source of negative and positive air ions, and that plants and green space are a minor source of negative air ions in the study garden. Moreover, temperature and humidity are positively and negatively affected negative air ions concentration, respectively. The proposed monitoring and mapping approach provides a way to effectively assess the patterns of negative and positive air ions in future landscape design projects.

  18. Recurrence quantification analysis applied to spatiotemporal pattern analysis in high-density mapping of human atrial fibrillation.

    Science.gov (United States)

    Zeemering, Stef; Bonizzi, Pietro; Maesen, Bart; Peeters, Ralf; Schotten, Ulrich

    2015-01-01

    Spatiotemporal complexity of atrial fibrillation (AF) patterns is often quantified by annotated intracardiac contact mapping. We introduce a new approach that applies recurrence plot (RP) construction followed by recurrence quantification analysis (RQA) to epicardial atrial electrograms, recorded with a high-density grid of electrodes. In 32 patients with no history of AF (aAF, n=11), paroxysmal AF (PAF, n=12) and persistent AF (persAF, n=9), RPs were constructed using a phase space electrogram embedding dimension equal to the estimated AF cycle length. Spatial information was incorporated by 1) averaging the recurrence over all electrodes, and 2) by applying principal component analysis (PCA) to the matrix of embedded electrograms and selecting the first principal component as a representation of spatial diversity. Standard RQA parameters were computed on the constructed RPs and correlated to the number of fibrillation waves per AF cycle (NW). Averaged RP RQA parameters showed no correlation with NW. Correlations improved when applying PCA, with maximum correlation achieved between RP threshold and NW (RR1%, r=0.68, p <; 0.001) and RP determinism (DET, r=-0.64, p <; 0.001). All studied RQA parameters based on the PCA RP were able to discriminate between persAF and aAF/PAF (DET persAF 0.40 ± 0.11 vs. 0.59 ± 0.14/0.62 ± 0.16, p <; 0.01). RP construction and RQA combined with PCA provide a quick and reliable tool to visualize dynamical behaviour and to assess the complexity of contact mapping patterns in AF.

  19. Mapping functional group free energy patterns at protein occluded sites: nuclear receptors and G-protein coupled receptors.

    Science.gov (United States)

    Lakkaraju, Sirish Kaushik; Yu, Wenbo; Raman, E Prabhu; Hershfeld, Alena V; Fang, Lei; Deshpande, Deepak A; MacKerell, Alexander D

    2015-03-23

    Occluded ligand-binding pockets (LBP) such as those found in nuclear receptors (NR) and G-protein coupled receptors (GPCR) represent a significant opportunity and challenge for computer-aided drug design. To determine free energies maps of functional groups of these LBPs, a Grand-Canonical Monte Carlo/Molecular Dynamics (GCMC/MD) strategy is combined with the Site Identification by Ligand Competitive Saturation (SILCS) methodology. SILCS-GCMC/MD is shown to map functional group affinity patterns that recapitulate locations of functional groups across diverse classes of ligands in the LBPs of the androgen (AR) and peroxisome proliferator-activated-γ (PPARγ) NRs and the metabotropic glutamate (mGluR) and β2-adreneric (β2AR) GPCRs. Inclusion of protein flexibility identifies regions of the binding pockets not accessible in crystal conformations and allows for better quantitative estimates of relative ligand binding affinities in all the proteins tested. Differences in functional group requirements of the active and inactive states of the β2AR LBP were used in virtual screening to identify high efficacy agonists targeting β2AR in Airway Smooth Muscle (ASM) cells. Seven of the 15 selected ligands were found to effect ASM relaxation representing a 46% hit rate. Hence, the method will be of use for the rational design of ligands in the context of chemical biology and the development of therapeutic agents.

  20. Detecting tactical patterns in basketball: comparison of merge self-organising maps and dynamic controlled neural networks.

    Science.gov (United States)

    Kempe, Matthias; Grunz, Andreas; Memmert, Daniel

    2015-01-01

    The soaring amount of data, especially spatial-temporal data, recorded in recent years demands for advanced analysis methods. Neural networks derived from self-organizing maps established themselves as a useful tool to analyse static and temporal data. In this study, we applied the merge self-organising map (MSOM) to spatio-temporal data. To do so, we investigated the ability of MSOM's to analyse spatio-temporal data and compared its performance to the common dynamical controlled network (DyCoN) approach to analyse team sport position data. The position data of 10 players were recorded via the Ubisense tracking system during a basketball game. Furthermore, three different pre-selected plays were recorded for classification. Following data preparation, the different nets were trained with the data of the first half. The training success of both networks was evaluated by achieved entropy. The second half of the basketball game was presented to both nets for automatic classification. Both approaches were able to present the trained data extremely well and to detect the pre-selected plays correctly. In conclusion, MSOMs are a useful tool to analyse spatial-temporal data, especially in team sports. By their direct inclusion of different time length of tactical patterns, they open up new opportunities within team sports.

  1. Active commuting to school: How far is too far?

    LENUS (Irish Health Repository)

    Nelson, Norah M

    2008-01-01

    ABSTRACT: BACKGROUND: Walking and cycling to school provide a convenient opportunity to incorporate physical activity into an adolescent\\'s daily routine. School proximity to residential homes has been identified as an important determinant of active commuting among children. The purpose of this study is to identify if distance is a barrier to active commuting among adolescents, and if there is a criterion distance above which adolescents choose not to walk or cycle. METHODS: Data was collected in 2003-05 from a cross-sectional cohort of 15-17 yr old adolescents in 61 post primary schools in Ireland. Participants self-reported distance, mode of transport to school and barriers to active commuting. Trained researchers took physical measurements of height and weight. The relation between mode of transport, gender and population density was examined. Distance was entered into a bivariate logistic regression model to predict mode choice, controlling for gender, population density socio-economic status and school clusters. RESULTS: Of the 4013 adolescents who participated (48.1% female, mean age 16.02 +\\/- 0.661), one third walked or cycled to school. A higher proportion of males than females commuted actively (41.0 vs. 33.8%, chi2 (1) = 22.21, p < 0.001, r = -0.074). Adolescents living in more densely populated areas had greater odds of active commuting than those in the most sparsely populated areas (chi2 (df = 3) = 839.64, p < 0.001). In each density category, active commuters travelled shorter distances to school. After controlling for gender and population density, a 1-mile increase in distance decreased the odds of active commuting by 71% (chi2 (df = 1) = 2591.86, p < 0.001). The majority of walkers lived within 1.5 miles and cyclists within 2.5 miles. Over 90% of adolescents who perceived distance as a barrier to active commuting lived further than 2.5 miles from school. CONCLUSION: Distance is an important perceived barrier to active commuting and a predictor

  2. Semantic mapping reveals distinct patterns in descriptions of social relations in adults with autism spectrum disorder.

    Science.gov (United States)

    Luo, Sean X; Shinall, Jacqueline A; Peterson, Bradley S; Gerber, Andrew J

    2016-08-01

    Adults with autism spectrum disorder (ASD) may describe other individuals differently compared with typical adults. In this study, we first asked participants to describe closely related individuals such as parents and close friends with 10 positive and 10 negative characteristics. We then used standard natural language processing methods to digitize and visualize these descriptions. The complex patterns of these descriptive sentences exhibited a difference in semantic space between individuals with ASD and control participants. Machine learning algorithms were able to automatically detect and discriminate between these two groups. Furthermore, we showed that these descriptive sentences from adults with ASD exhibited fewer connections as defined by word-word co-occurrences in descriptions, and these connections in words formed a less "small-world" like network. Autism Res 2016, 9: 846-853. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  3. The Commuting Graph of the Symmetric Inverse Semigroup

    CERN Document Server

    Araújo, João; Konieczny, Janusz

    2012-01-01

    The commuting graph of a finite non-commutative semigroup $S$, denoted $\\cg(S)$, is a simple graph whose vertices are the non-central elements of $S$ and two distinct vertices $x,y$ are adjacent if $xy=yx$. Let $\\mi(X)$ be the symmetric inverse semigroup of partial injective transformations on a finite set $X$. The semigroup $\\mi(X)$ has the symmetric group $\\sym(X)$ of permutations on $X$ as its group of units. In 1989, Burns and Goldsmith determined the clique number of the commuting graph of $\\sym(X)$. In 2008, Iranmanesh and Jafarzadeh found an upper bound of the diameter of $\\cg(\\sym(X))$, and in 2011, Dol\\u{z}an and Oblak claimed (but their proof has a GAP) that this upper bound is in fact the exact value. The goal of this paper is to begin the study of the commuting graph of the symmetric inverse semigroup $\\mi(X)$. We calculate the clique number of $\\cg(\\mi(X))$, the diameters of the commuting graphs of the proper ideals of $\\mi(X)$, and the diameter of $\\cg(\\mi(X))$ when $|X|$ is even or a power of a...

  4. Bias Assessment of General Chemistry Analytes using Commutable Samples.

    Science.gov (United States)

    Koerbin, Gus; Tate, Jillian R; Ryan, Julie; Jones, Graham Rd; Sikaris, Ken A; Kanowski, David; Reed, Maxine; Gill, Janice; Koumantakis, George; Yen, Tina; St John, Andrew; Hickman, Peter E; Simpson, Aaron; Graham, Peter

    2014-11-01

    Harmonisation of reference intervals for routine general chemistry analytes has been a goal for many years. Analytical bias may prevent this harmonisation. To determine if analytical bias is present when comparing methods, the use of commutable samples, or samples that have the same properties as the clinical samples routinely analysed, should be used as reference samples to eliminate the possibility of matrix effect. The use of commutable samples has improved the identification of unacceptable analytical performance in the Netherlands and Spain. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) has undertaken a pilot study using commutable samples in an attempt to determine not only country specific reference intervals but to make them comparable between countries. Australia and New Zealand, through the Australasian Association of Clinical Biochemists (AACB), have also undertaken an assessment of analytical bias using commutable samples and determined that of the 27 general chemistry analytes studied, 19 showed sufficiently small between method biases as to not prevent harmonisation of reference intervals. Application of evidence based approaches including the determination of analytical bias using commutable material is necessary when seeking to harmonise reference intervals.

  5. Effect of environmental sound familiarity on dynamic neural activation/inhibition patterns: an ERD mapping study.

    Science.gov (United States)

    Lebrun, N; Clochon, P; Etévenon, P; Baron, J C; Eustache, F

    1998-07-01

    The aim of this study was to analyze the timing and topography of brain activity in relation to the cognitive processing of different types of auditory information. We specifically investigated the effects of familiarity on environmental sound identification, an issue which has been little studied with respect to cognitive processes, neural substrates, and time course of brain activity. To address this issue, we implemented and applied an electroencephalographic mapping method named event-related desynchronization, which allows one to assess the dynamics of neuronal activity with high temporal resolution (here, 125 ms); we used 19 recording electrodes with standard positioning. We designed an activation paradigm in which healthy subjects were asked to discriminate binaurally heard sounds belonging to one of two distinct categories, "familiar" (i.e., natural environmental sounds) or "unfamiliar" (i.e., altered environmental sounds). The sounds were selected according to strict preexperimental tests so that the former should engage greater semantic, and the latter greater structural, analysis, which we predicted to preferentially implicate left posterior and right brain regions, respectively. During the stimulations, significant desynchronizations (thought to reflect neuronal activations) were recorded over left hemisphere regions for familiar sounds and right temporofrontal regions for unfamiliar sounds, but with only few significant differences between the two sound categories and a common bilateral activation in the frontal regions. However, strongly significant differences between familiar and unfamiliar sounds occurred near the end of and following the stimulations, due to synchronizations (though to reflect deactivations) which appeared over the left posterior regions, as well as the vertex and bilateral frontal cortex, only after unfamiliar sounds. These unexpected synchronizations after the unfamiliar stimuli may reflect an awareness of the unfamiliarity of

  6. An Experimental Study of Liquid-Liquid Microflow Pattern Maps Accompanied with Mass Transfer

    Institute of Scientific and Technical Information of China (English)

    邵华伟; 吕阳成; 王凯; 骆广生

    2012-01-01

    This paper presents the experimental results of liquid-liquid microflows in a coaxial microfluidic device with mass transfer. Three working systems were n-butanol + phosphoric acid (PA) + water, methyl isobutyl ketone (MIBK) + PA + water, 30% kerosene in tri-n-butylphosphate (TBP)+ PA + water. The direction and intensity of mass transfer were adjusted by adding PA in one of two phases mutual saturated in advance. When PA transferred from the organic phase to the aqueous phase, tiny aqueous droplets may generate inside the organic phase by mass transfer inducement to form a new W/O/W flow pattern directly on some special cases. Once the PA concentration was very high, violent Marangoni effect could be observed to throw part of organic phase out of droplets as tail. The interphase transfer of PA could expand the jetting flow region, in particular for systems with low or medium interfacial tension and when the mass transfer direction was from the aqueous phase to the organic phase.

  7. Optimization of polynomials in non-commuting variables

    CERN Document Server

    Burgdorf, Sabine; Povh, Janez

    2016-01-01

    This book presents recent results on positivity and optimization of polynomials in non-commuting variables. Researchers in non-commutative algebraic geometry, control theory, system engineering, optimization, quantum physics and information science will find the unified notation and mixture of algebraic geometry and mathematical programming useful. Theoretical results are matched with algorithmic considerations; several examples and information on how to use NCSOStools open source package to obtain the results provided. Results are presented on detecting the eigenvalue and trace positivity of polynomials in non-commuting variables using Newton chip method and Newton cyclic chip method, relaxations for constrained and unconstrained optimization problems, semidefinite programming formulations of the relaxations and finite convergence of the hierarchies of these relaxations, and the practical efficiency of algorithms.

  8. Harmonic-free line-commutated ac/dc rectifiers

    Energy Technology Data Exchange (ETDEWEB)

    Villablanca, Miguel E. [Electrical Engineering Department, University of Santiago, P.O. Box 10233, Santiago (Chile)

    2009-11-15

    In this paper both a method and apparatus are applied to different configurations of line-commutated ac/dc rectifiers to reduce the distortion of currents flowing from the ac supply. The load may be either inductive or capacitive. The technology involves an accurate shaping of the dc current by using two self-commutated switches. This dc-current shaping is reflected back into the shaping of the ac input currents, which become pure sine waves. Thyristor-based rectifying operation is possible with a simple control circuit, which is able to deal with both rapid load variations and failures in the self-commutated switches. Furthermore, the overlap conduction of bridge thyristors is eliminated completely. Experimental verification is provided from a 400-V 30-kVA 50-Hz laboratory prototype. (author)

  9. Non-topological non-commutativity in string theory

    CERN Document Server

    Guttenberg, Sebastian; Kreuzer, Maximilian; Rashkov, Radoslav

    2007-01-01

    Quantization of coordinates leads to the non-commutative product of deformation quantization, but is also at the roots of string theory, for which space-time coordinates become the dynamical fields of a two-dimensional conformal quantum field theory. Appositely, open string diagrams provided the inspiration for Kontsevich's solution of the long-standing problem of quantization of Poisson geometry by virtue of his formality theorem. In the context of D-brane physics non-commutativity is not limited, however, to the topolocial sector. We show that non-commutative effective actions still make sense when associativity is lost and establish a generalized Connes-Flato-Sternheimer condition through second order in a derivative expansion. The measure in general curved backgrounds is naturally provided by the Born--Infeld action and reduces to the symplectic measure in the topological limit, but remains non-singular even for degenerate Poisson structures. Analogous superspace deformations by RR--fields are also discus...

  10. 3D maps from multiple MRI illustrate changing atrophy patterns as subjects progress from mild cognitive impairment to Alzheimer's disease.

    Science.gov (United States)

    Whitwell, Jennifer L; Przybelski, Scott A; Weigand, Stephen D; Knopman, David S; Boeve, Bradley F; Petersen, Ronald C; Jack, Clifford R

    2007-07-01

    Mild cognitive impairment (MCI), particularly the amnestic subtype (aMCI), is considered as a transitional stage between normal aging and a diagnosis of clinically probable Alzheimer's disease (AD). The aMCI construct is particularly useful as it provides an opportunity to assess a clinical stage which in most subjects represents prodromal AD. The aim of this study was to assess the progression of cerebral atrophy over multiple serial MRI during the period from aMCI to progression to AD. Thirty-three subjects were selected that fulfilled clinical criteria for aMCI and had three serial MRI scans: the first scan approximately 3 years before the diagnosis of AD, the second scan approximately 1 year before, and the third scan at the time of the diagnosis of AD. A group of 33 healthy controls were age and gender-matched to the study cohort. Voxel-based morphometry (VBM) was used to assess patterns of grey matter atrophy in the aMCI subjects at each time-point compared to the control group. Customized templates and prior probability maps were used to avoid normalization and segmentation bias. The pattern of grey matter loss in the aMCI subject scans that were 3 years before the diagnosis of AD was focused primarily on the medial temporal lobes, including the amygdala, anterior hippocampus and entorhinal cortex, with some additional involvement of the fusiform gyrus, compared to controls. The extent and magnitude of the cerebral atrophy further progressed by the time the subjects were 1 year before the diagnosis of AD. At this point atrophy in the temporal lobes spread to include the middle temporal gyrus, and extended into more posterior regions of the temporal lobe to include the entire extent of the hippocampus. The parietal lobe also started to become involved. By the time the subjects had progressed to a clinical diagnosis of AD the pattern of grey matter atrophy had become still more widespread with more severe involvement of the medial temporal lobes and the

  11. Urban growth patterns in major Southeast Asian cities: Toward exposure mapping and vulnerability assessment

    Science.gov (United States)

    Mandapaka, Pradeep; Kamarajugedda, Shankar A.; Lo, Edmond Y. M.

    2017-04-01

    Southeast Asia (SEA) is undergoing rapid urbanization, with urban population percentage increasing from 32% in 1990 to 48% in 2015. It is projected that by the year 2040, urban regions in SEA account for 60% of its total population. The region is home to 600 million people, with many densely populated cities, including megacities such as Jakarta, Bangkok, and Manila. The region has more than 20,000 islands, and many cities lie on coastal low-lands and floodplains. These geographical characteristics together with the increasing population, infrastructure growth, and changing climate makes the region highly vulnerable to natural hazards. This study assessed urban growth dynamics in major (defined as population exceeding 1 million) SEA cities using remotely sensed night-time lights (NTL) data. A recently proposed brightness gradient approach was applied on 21 years (1992-2012) of NTL annual composites to derive core-urban (CU) and peri-urban (PU) regions within each city. The study also assessed the sensitivity of above extracted urban categories to different NTL thresholds. The temporal trends in CU and PU regions were quantified, and compared with trends in socio-economic indicators. The spatial expansion of CU and PU regions were found to depend on geographical constraints and socio-economic factors. Quantification of urban growth spatial-temporal patterns, as conducted here contributes towards the understanding of exposure and vulnerability of people and infrastructures to natural hazards, as well as the evolving trends for assessment under projected urbanization conditions. This will underpin better risk assessment efforts for present and future planning.

  12. Quantum dynamics of simultaneously measured non-commuting observables

    Science.gov (United States)

    Hacohen-Gourgy, Shay; Martin, Leigh S.; Flurin, Emmanuel; Ramasesh, Vinay V.; Whaley, K. Birgitta; Siddiqi, Irfan

    2016-10-01

    In quantum mechanics, measurements cause wavefunction collapse that yields precise outcomes, whereas for non-commuting observables such as position and momentum Heisenberg’s uncertainty principle limits the intrinsic precision of a state. Although theoretical work has demonstrated that it should be possible to perform simultaneous non-commuting measurements and has revealed the limits on measurement outcomes, only recently has the dynamics of the quantum state been discussed. To realize this unexplored regime, we simultaneously apply two continuous quantum non-demolition probes of non-commuting observables to a superconducting qubit. We implement multiple readout channels by coupling the qubit to multiple modes of a cavity. To control the measurement observables, we implement a ‘single quadrature’ measurement by driving the qubit and applying cavity sidebands with a relative phase that sets the observable. Here, we use this approach to show that the uncertainty principle governs the dynamics of the wavefunction by enforcing a lower bound on the measurement-induced disturbance. Consequently, as we transition from measuring identical to measuring non-commuting observables, the dynamics make a smooth transition from standard wavefunction collapse to localized persistent diffusion and then to isotropic persistent diffusion. Although the evolution of the state differs markedly from that of a conventional measurement, information about both non-commuting observables is extracted by keeping track of the time ordering of the measurement record, enabling quantum state tomography without alternating measurements. Our work creates novel capabilities for quantum control, including rapid state purification, adaptive measurement, measurement-based state steering and continuous quantum error correction. As physical systems often interact continuously with their environment via non-commuting degrees of freedom, our work offers a way to study how notions of contemporary

  13. Decreasing the commutation failure frequency in HVDC transmission systems

    DEFF Research Database (Denmark)

    Hansen (retired June, 2000), Arne; Havemann (retired June, 2000), Henrik

    2000-01-01

    with equidistant firing pulses to a strategy that takes into consideration the potentially dangerous voltage changes on the supply lines, If the supply voltages are monitored continuously, it is possible to calculate the necessity of advancing the firing pulses to avoid commutation failures. In the paper......In this paper we show how a fairly large proportion of those commutation failures that are due to single-phased short circuits to earth can be avoided. In a control circuit based on a digital signal processor (DSP) it is possible, with instantaneous results, to switch from a normal control strategy...

  14. Noetherianity of some degree two twisted skew-commutative algebras

    OpenAIRE

    Nagpal, Rohit; Sam, Steven V; Snowden, Andrew

    2016-01-01

    A major open problem in the theory of twisted commutative algebras (tca's) is proving noetherianity of finitely generated tca's. For bounded tca's this is easy, in the unbounded case, noetherianity is only known for Sym(Sym^2(C^\\infty)) and Sym(\\wedge^2(C^\\infty)). In this paper, we establish noetherianity for the skew-commutative versions of these two algebras, namely \\wedge(Sym^2(C^\\infty)) and \\wedge(\\wedge^2(C^\\infty)). The result depends on work of Serganova on the representation theory ...

  15. A non-commutative framework for topological insulators

    Science.gov (United States)

    Bourne, C.; Carey, A. L.; Rennie, A.

    2016-04-01

    We study topological insulators, regarded as physical systems giving rise to topological invariants determined by symmetries both linear and anti-linear. Our perspective is that of non-commutative index theory of operator algebras. In particular, we formulate the index problems using Kasparov theory, both complex and real. We show that the periodic table of topological insulators and superconductors can be realized as a real or complex index pairing of a Kasparov module capturing internal symmetries of the Hamiltonian with a spectral triple encoding the geometry of the sample’s (possibly non-commutative) Brillouin zone.

  16. Non-commutative black holes in D dimensions

    CERN Document Server

    Klimcík, C; Pompos, A

    1994-01-01

    Recently introduced classical theory of gravity in non-commutative geometry is studied. The most general (four parametric) family of D dibensional static spherically symmetric spacetimes is identified and its properties are studied in detail. For wide class of the choices of parameters, the corresponding spacetimes have the structure of asymptotically flat black holes with a smooth event horizon hiding the curvature singularity. A specific attention is devoted to the behavior of components of the metric in non-commutative direction, which are interpreted as the black hole hair.

  17. Exotic Galilean Symmetry and Non-Commutative Mechanics

    Directory of Open Access Journals (Sweden)

    Peter A. Horváthy

    2010-07-01

    Full Text Available Some aspects of the ''exotic'' particle, associated with the two-parameter central extension of the planar Galilei group are reviewed. A fundamental property is that it has non-commuting position coordinates. Other and generalized non-commutative models are also discussed. Minimal as well as anomalous coupling to an external electromagnetic field is presented. Supersymmetric extension is also considered. Exotic Galilean symmetry is also found in Moyal field theory. Similar equations arise for a semiclassical Bloch electron, used to explain the anomalous/spin/optical Hall effects.

  18. Features of Synchronous Electronically Commutated Motors in Servomotor Operation Modes

    Directory of Open Access Journals (Sweden)

    Dirba J.

    2017-04-01

    Full Text Available The authors consider the features and operation specifics of the synchronous permanent magnet motors and the synchronous reluctance motors with electronic commutation in servomotor operation modes. Calculation results show that mechanical and control characteristics of studied motors are close to a linear shape. The studied motor control is proposed to implement similar to phase control of induction servomotor; it means that angle θ (angle between vectors of the supply voltage and non-load electromotive force or angle ε (angle between rotor direct axis and armature magnetomotive force axis is changed. The analysis results show that synchronous electronically commutated motors could be used as servomotors.

  19. Features of Synchronous Electronically Commutated Motors in Servomotor Operation Modes

    Science.gov (United States)

    Dirba, J.; Lavrinovicha, L.; Dobriyan, R.

    2017-04-01

    The authors consider the features and operation specifics of the synchronous permanent magnet motors and the synchronous reluctance motors with electronic commutation in servomotor operation modes. Calculation results show that mechanical and control characteristics of studied motors are close to a linear shape. The studied motor control is proposed to implement similar to phase control of induction servomotor; it means that angle θ (angle between vectors of the supply voltage and non-load electromotive force) or angle ɛ (angle between rotor direct axis and armature magnetomotive force axis) is changed. The analysis results show that synchronous electronically commutated motors could be used as servomotors.

  20. Modular Theory, Non-Commutative Geometry and Quantum Gravity

    Directory of Open Access Journals (Sweden)

    Wicharn Lewkeeratiyutkul

    2010-08-01

    Full Text Available This paper contains the first written exposition of some ideas (announced in a previous survey on an approach to quantum gravity based on Tomita-Takesaki modular theory and A. Connes non-commutative geometry aiming at the reconstruction of spectral geometries from an operational formalism of states and categories of observables in a covariant theory. Care has been taken to provide a coverage of the relevant background on modular theory, its applications in non-commutative geometry and physics and to the detailed discussion of the main foundational issues raised by the proposal.

  1. Commuting Quasihomogeneous Toeplitz Operator and Hankel Operator on Weighted Bergman Space

    Directory of Open Access Journals (Sweden)

    Jun Yang

    2013-01-01

    Full Text Available We characterize the commuting Toeplitz operator and Hankel operator with quasihomogeneous symbols. Also, we use it to show the necessary and sufficient conditions for commuting Toeplitz operator and Hankel operator with ordinary functions.

  2. Another version of “exotic characterization of a commutative H∗-algebra”

    Directory of Open Access Journals (Sweden)

    Parfeny P. Saworotnow

    2005-01-01

    Full Text Available Commutative H∗-algebra is characterized in a somewhat unusual fashion without assuming either Hilbert space structure or commutativity. Existence of an involution is not postulated also.

  3. Comparison of glomerular activity patterns by fMRI and wide-field calcium imaging: Implications for principles underlying odor mapping.

    Science.gov (United States)

    Sanganahalli, Basavaraju G; Rebello, Michelle R; Herman, Peter; Papademetris, Xenophon; Shepherd, Gordon M; Verhagen, Justus V; Hyder, Fahmeed

    2016-02-01

    Functional imaging signals arise from distinct metabolic and hemodynamic events at the neuropil, but how these processes are influenced by pre- and post-synaptic activities need to be understood for quantitative interpretation of stimulus-evoked mapping data. The olfactory bulb (OB) glomeruli, spherical neuropil regions with well-defined neuronal circuitry, can provide insights into this issue. Optical calcium-sensitive fluorescent dye imaging (OICa(2+)) reflects dynamics of pre-synaptic input to glomeruli, whereas high-resolution functional magnetic resonance imaging (fMRI) using deoxyhemoglobin contrast reveals neuropil function within the glomerular layer where both pre- and post-synaptic activities contribute. We imaged odor-specific activity patterns of the dorsal OB in the same anesthetized rats with fMRI and OICa(2+) and then co-registered the respective maps to compare patterns in the same space. Maps by each modality were very reproducible as trial-to-trial patterns for a given odor, overlapping by ~80%. Maps evoked by ethyl butyrate and methyl valerate for a given modality overlapped by ~80%, suggesting activation of similar dorsal glomerular networks by these odors. Comparison of maps generated by both methods for a given odor showed ~70% overlap, indicating similar odor-specific maps by each method. These results suggest that odor-specific glomerular patterns by high-resolution fMRI primarily tracks pre-synaptic input to the OB. Thus combining OICa(2+) and fMRI lays the framework for studies of OB processing over a range of spatiotemporal scales, where OICa(2+) can feature the fast dynamics of dorsal glomerular clusters and fMRI can map the entire glomerular sheet in the OB.

  4. A deterministic polynomial time algorithm for non-commutative rational identity testing with applications

    OpenAIRE

    2015-01-01

    In this paper we present a deterministic polynomial time algorithm for testing if a symbolic matrix in non-commuting variables over $\\mathbb{Q}$ is invertible or not. The analogous question for commuting variables is the celebrated polynomial identity testing (PIT) for symbolic determinants. In contrast to the commutative case, which has an efficient probabilistic algorithm, the best previous algorithm for the non-commutative setting required exponential time (whether or not randomization is ...

  5. Associations between long commutes and subjective health complaints among railway workers in Norway

    Directory of Open Access Journals (Sweden)

    Terhi Urhonen

    2016-12-01

    Full Text Available Commuting is an important aspect of daily life for many employees, but there is little knowledge of how this affects individual commuters' health and well-being. The authors investigated the relationship between commuting and subjective health complaints, using data from a web-based questionnaire. In a sample of 2126 railway employees, 644 (30.3% had long commute times. A 29-item inventory was used to measure the number and degree of the subjective health complaints. Those who commuted 60 min or more each way were characterized by significantly higher numbers and degrees of subjective health complaints compared with their peers with short commutes. The mean number of complaints was 7.5 among the former group and 6.4 for the latter group (p = 0.009. In a regression model, in which the authors controlled for age, gender, education, self-rated health, and coping, the employees with long commutes reported more complaints than those with short commutes. Significant associations were found between those with long commutes and the number and degree of incidences of self-reported musculoskeletal pain, pseudo-neurologic complaints, and gastrointestinal problems. Commuters who had had long commutes for more than 10 years reported more gastrointestinal and musculoskeletal complaints than those with long commutes for less than 2 years. Also, commuters with long commutes spent less time with their families and leisure activities compared with those with short commutes. The authors conclude that the association between long commute times and higher levels of subjective health complaints should attract the attention of transport planners, employers, and public health policymaker.

  6. Associations between long commutes and subjective health complaints among railway workers in Norway.

    Science.gov (United States)

    Urhonen, Terhi; Lie, Arve; Aamodt, Geir

    2016-12-01

    Commuting is an important aspect of daily life for many employees, but there is little knowledge of how this affects individual commuters' health and well-being. The authors investigated the relationship between commuting and subjective health complaints, using data from a web-based questionnaire. In a sample of 2126 railway employees, 644 (30.3%) had long commute times. A 29-item inventory was used to measure the number and degree of the subjective health complaints. Those who commuted 60 min or more each way were characterized by significantly higher numbers and degrees of subjective health complaints compared with their peers with short commutes. The mean number of complaints was 7.5 among the former group and 6.4 for the latter group (p = 0.009). In a regression model, in which the authors controlled for age, gender, education, self-rated health, and coping, the employees with long commutes reported more complaints than those with short commutes. Significant associations were found between those with long commutes and the number and degree of incidences of self-reported musculoskeletal pain, pseudo-neurologic complaints, and gastrointestinal problems. Commuters who had had long commutes for more than 10 years reported more gastrointestinal and musculoskeletal complaints than those with long commutes for less than 2 years. Also, commuters with long commutes spent less time with their families and leisure activities compared with those with short commutes. The authors conclude that the association between long commute times and higher levels of subjective health complaints should attract the attention of transport planners, employers, and public health policymaker.

  7. Sensitivity of Self-Organizing Map surface current patterns to the use of radial vs. Cartesian input vectors measured by high-frequency radars

    Science.gov (United States)

    Kalinić, Hrvoje; Mihanović, Hrvoje; Cosoli, Simone; Vilibić, Ivica

    2015-11-01

    In this paper, the Self-Organizing Map (SOM) method was applied to the surface currents data obtained between February and November 2008 by a network of high-frequency (HF) radars in the northern Adriatic. The sensitivity of the derived SOM solutions was tested in respect to the change of coordinate system of the data introduced to the SOM. In one experiment the original radial data measurements were used, and in the other experiment the Cartesian (total) current vectors derived from original radar data were analyzed. Although the computation of SOM solutions was not a demanding task, comparing both neural lattices yielded the nondeterministic polynomial time (NP) problem for which is difficult to propose a solution that will be globally optimal. Thus, we suggested utilizing the greedy algorithm with underlying assumption of 1-to-1 mapping between lattices. The results suggested that such solution could be local, but not global optimum and that the latter assumption could lower the obtained correlations between the patterns. However, without the assumption of 1-to-1 mapping between lattices, correlation between the derived SOM patterns was quite high, indicating that SOM mapping introduced to the radial current vectors and subsequent transformation into Cartesian coordinate system does not significantly affect obtained patterns in comparison to the SOM mapping done on the derived Cartesian current vectors. The documented similarity corroborates the use of total current vectors in various oceanographic studies, as being representative derivative of original radial measurements.

  8. 20 CFR 704.102 - Commutation of payments to aliens and nonresidents.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Commutation of payments to aliens and... LHWCA EXTENSIONS Defense Base Act § 704.102 Commutation of payments to aliens and nonresidents. Authority to commute payments to aliens and nonnationals who are not residents of the United States and...

  9. A Pareto Improving Strategy for the Time-Dependent Morning Commute Problem

    OpenAIRE

    Garcia, Reinaldo Crispiniano

    1999-01-01

    This dissertation describes a strategy which makes all commuters better off (i.e. a Pareto effecient strategy) for the time-dependent morning commute problem, even if the collected revenues are not returned to the population of commuters. The proposed strategy will apply road pricing as a tool for congestion management, a practice usually called congestion pricing. 

  10. The Z-> gamma gamma,gg decays in the non-commutative standard model

    CERN Document Server

    Behr, W; Duplancic, G; Schupp, P; Trampetic, J; Wess, J

    2003-01-01

    On non-commutative spacetime, the standard model (SM) allows new, usually SM forbidden, triple gauge boson interactions to occur. In this letter we propose the SM strictly forbidden Z-> gamma gamma and Z->gg decay modes coming from the gauge sector of the non-commutative standard model (NCSM) as a place where non-commutativity could be experimentally discovered. (orig.)

  11. The commuter family as a geographical adaptive strategy for the work-family balance

    NARCIS (Netherlands)

    van der Klis, M.; Karsten, L.

    2009-01-01

    In this paper we raise the question of how commuter families create a work-family balance in a situation of incongruity of the geographical scales of work and family. Commuter families combine the work location of a commuting parent on the (inter)national scale, with the home-based parent's work loc

  12. 49 CFR 37.87 - Purchase or lease of used intercity and commuter rail cars.

    Science.gov (United States)

    2010-10-01

    ... commuter rail cars from any source. (e) Amtrak and commuter authorities purchasing or leasing used... rail cars. 37.87 Section 37.87 Transportation Office of the Secretary of Transportation TRANSPORTATION....87 Purchase or lease of used intercity and commuter rail cars. (a) Except as provided elsewhere...

  13. Active commuting and habit strength: an interactive and discriminant analyses approach

    NARCIS (Netherlands)

    de Bruijn, G.-J.; Gardner, B.

    2011-01-01

    Purpose. Habits may be a mechanism linking environmental variables with active commuting. This study investigated the role of habit strength in the explanation of active commuting across profiles based on current active commuting, motivation, and habit strength within the framework of the theory of

  14. Commutative-like Encryption: A New Characterization of ElGamal

    OpenAIRE

    Dai, Wei

    2010-01-01

    Commutative encryption is a useful but rather strict notion in cryptography. In this paper, we deny a loose variation of commutative encryption-commutative-like encryption and give an example: the generalization of ElGamal scheme. The application of the new variation is also discussed.

  15. Investigating commuting flexibility with GPS data and 3D geovisualization: a case study of Beijing, China

    NARCIS (Netherlands)

    Shen, Y.; Kwan, M.-P.; Chai, Y.

    2013-01-01

    Using the notion of commuting flexibility, this paper investigates the intra-personal day-to-day variability and flexibility of commuting behavior using a 7-day GPS dataset collected in Beijing, China. Four dimensions of commuting variability are evaluated: space, time, travel mode, and travel route

  16. Mapping Diversity of Publication Patterns in the Social Sciences and Humanities: An Approach Making Use of Fuzzy Cluster Analysis

    Directory of Open Access Journals (Sweden)

    Frederik T. Verleysen

    2016-11-01

    Full Text Available Purpose: To present a method for systematically mapping diversity of publication patterns at the author level in the social sciences and humanities in terms of publication type, publication language and co-authorship. Design/methodology/approach: In a follow-up to the hard partitioning clustering by Verleysen and Weeren in 2016, we now propose the complementary use of fuzzy cluster analysis, making use of a membership coefficient to study gradual differences between publication styles among authors within a scholarly discipline. The analysis of the probability density function of the membership coefficient allows to assess the distribution of publication styles within and between disciplines. Findings: As an illustration we analyze 1,828 productive authors affiliated in Flanders, Belgium. Whereas a hard partitioning previously identified two broad publication styles, an international one vs. a domestic one, fuzzy analysis now shows gradual differences among authors. Internal diversity also varies across disciplines and can be explained by researchers' specialization and dissemination strategies. Research limitations: The dataset used is limited to one country for the years 2000-2011; a cognitive classification of authors may yield a different result from the affiliation-based classification used here. Practical implications: Our method is applicable to other bibliometric and research evaluation contexts, especially for the social sciences and humanities in non-Anglophone countries. Originality/value: The method proposed is a novel application of cluster analysis to the field of bibliometrics. Applied to publication patterns at the author level in the social sciences and humanities, for the first time it systematically documents intra-disciplinary diversity.

  17. Non-commutative Field Theory on S^4

    CERN Document Server

    Nakayama, R; Nakayama, Ryuichi; Shimono, Yusuke

    2004-01-01

    In the previous paper (hep-th/0402010) we proposed a matrix configuration for a non-commutative S^4 (NC4S) and constructed a non-commutative (star) product for field theories on NC4S. This star product and the functions on NC4S turned out to be singular (ambiguous) on a circle on S^4. In the present paper we will show that any matrix can be expanded in terms of the matrix configuration representing NC4S just like any matrix can be expanded into symmetrized products of the matrix configuration for non-commutative S^2. Then we will show that the singularities of the functions on S^4 and the star product can be removed by covering the (commutative) manifold by coordinate neighborhoods and performing appropriate coordinate transformations. Finally a scalar field theory on NC4S is constructed. Our matrix configuration describes two S^4's joined at the circle and the Matrix theory action contains a projection matrix inside the trace to restrict the space of matrices to that for one S^4.

  18. Seasonal and socio-demographic determinants of school commuting

    DEFF Research Database (Denmark)

    Bjørkelund Børrestad, Line Anita; Andersen, Lars Bo; Bere, Elling

    2011-01-01

    OBJECTIVE: To report prevalence of commuting to school in Norway with regard to season, gender, parental education level, ethnicity and distance to school. METHODS: Cross-sectional questionnaire data from the Fruits and Vegetables Make the Marks project collected in 2008, including 1,339 ten to t...

  19. Procreating Tiles of Double Commutative-Step Digraphs

    Institute of Scientific and Technical Information of China (English)

    Jian-qin Zhou

    2008-01-01

    Double commutative-step digraph generalizes the double-loop digraph. A double commutative-step digraph can be represented by an L-shaped tile, which periodically tessellates the plane. Given an initial tile L(l, h,x, y), Agniló et al. define a discrete iteration L(p) = L(l + 2p, h + 2p, x + p, y + p),p = 0, 1, 2,…, over L-shapes (equivalently over double commutative-step digraphs), and obtain an orbit generated by L(l, h, x, y),which is said to be a procreating k-tight tile if L(p)(p= 0, 1, 2,… ) are all k-tight tiles. They classify the set of L-shaped tiles by its behavior under the above-mentioned discrete dynamics and obtain some procreating tiles of double commutative-step digraphs. In this work, with an approach proposed by Li and Xu et al., we define some new discrete iteration over L-shapes and classify the set of tiles by the procreating condition. We also propose some approaches to find infinite families of realizable k-tight tiles starting from any realizable k-tight L-shaped tile L(l, h, x, y), 0≤|y - x|≤ 2k + 2. As an example, we present an infinite family of 3-tight optimal double-loop networks to illustrate our approaches.

  20. On W algebras commuting with a set of screenings

    CERN Document Server

    Litvinov, Alexey

    2016-01-01

    We consider the problem of classification of all W algebras which commute with a set of exponential screening operators. Assuming that the W algebra has a nontrivial current of spin 3, we find equations satisfied by the screening operators and classify their solutions.

  1. On W algebras commuting with a set of screenings

    Science.gov (United States)

    Litvinov, Alexey; Spodyneiko, Lev

    2016-11-01

    We consider the problem of classification of all W algebras which commute with a set of exponential screening operators. Assuming that the W algebra has a nontrivial current of spin 3, we find equations satisfied by the screening operators and classify their solutions.

  2. How well do cognitive and environmental variables predict active commuting?

    Directory of Open Access Journals (Sweden)

    Godin Gaston

    2009-03-01

    Full Text Available Abstract Background In recent years, there has been growing interest in theoretical studies integrating cognitions and environmental variables in the prediction of behaviour related to the obesity epidemic. This is the approach adopted in the present study in reference to the theory of planned behaviour. More precisely, the aim of this study was to determine the contribution of cognitive and environmental variables in the prediction of active commuting to get to and from work or school. Methods A prospective study was carried out with 130 undergraduate and graduate students (93 females; 37 males. Environmental, cognitive and socio-demographic variables were evaluated at baseline by questionnaire. Two weeks later, active commuting (walking/bicycling to get to and from work or school was self-reported by questionnaire. Hierarchical multiple regression analyses were performed to predict intention and behaviour. Results The model predicting behaviour based on cognitive variables explained more variance than the model based on environmental variables (37.4% versus 26.8%; Z = 3.86, p p p Conclusion The results showed that cognitive variables play a more important role than environmental variables in predicting and explaining active commuting. When environmental variables were significant, they were mediated by cognitive variables. Therefore, individual cognitions should remain one of the main focuses of interventions promoting active commuting among undergraduate and graduate students.

  3. The entropy of dense non-commutative fermion gases

    CERN Document Server

    Kriel, Johannes N

    2011-01-01

    We investigate the properties of two- and three-dimensional non-commutative fermion gases with fixed total z-component of angular momentum, J_z, and at high density for the simplest form of non-commutativity involving constant spatial commutators. Analytic expressions for the entropy and pressure are found. The entropy exhibits non-extensive behaviour while the pressure reveals the presence of incompressibility in two, but not in three dimensions. Remarkably, for two-dimensional systems close to the incompressible density, the entropy is proportional to the square root of the system size, i.e., for such systems the number of microscopic degrees of freedom is determined by the circumference, rather than the area (size) of the system. The absence of incompressibility in three dimensions, and subsequently also the absence of a scaling law for the entropy analogous to the one found in two dimensions, is attributed to the form of the non-commutativity used here, the breaking of the rotational symmetry it implies a...

  4. Commutative Semigroups and a Generalization of the Concept of Mean

    Science.gov (United States)

    Biasi, C.; Zuffi, E.M.

    2005-01-01

    The main purpose in this note is to provide a generalization of the concept of mean, using the algebraic structure of commutative semigroups. Also, the pedagogical aim is to discuss with undergraduate math students the idea of generalizing a concept or a structure as a typical mathematical activity.

  5. A commuting network model: going to the bulk

    CERN Document Server

    Gargiulo, Floriana; Huet, Sylvie; Espinosa, Omar Baqueiro

    2011-01-01

    The influence of commuting in socio-economic dynamics increases constantly. Analysing and modelling the networks formed by commuters to help decision-making regarding the land-use has become crucial. This paper presents a simple spatial interaction simulated model with only one parameter. The proposed algorithm considers each individual who wants to commute, starting from their living place to all their workplaces. It decides where the location of the workplace following the classical rule inspired from the gravity law consisting in a compromise between the job offers and the distance to the jobs. The further away the job offer is, the more important it must be in order to be considered. Inversely, only the quantity of offers is important for the decision when these offers are close. The paper also presents a comparative analysis of the structure of the commuting networks of the four European regions to which we apply our model. The model is calibrated and validated on these regions. Results from the analysis...

  6. Resident and Commuter Students: Is It Only the Living Situation?

    Science.gov (United States)

    Welty, John D.

    1976-01-01

    The impact of the residence hall and commuter living situations on a freshman's intellectual and personal growth is studied. The study affirms previous findings that residence hall freshmen develop more rapidly, but the results suggest that other college experience factors beyond the living situation are important in facilitating student…

  7. Compactness of the commutators of parabolic singular integrals

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,the authors prove that the commutator [b,T] of the parabolic singular integrals is a compact operator on Lp(Rn)(1 < p < ∞) if and only if b ∈ VMO(Rn,ρ).The result is substantial improvement and extension of some known results.

  8. Commutators on Lipschitz spaces and related function spaces

    Institute of Scientific and Technical Information of China (English)

    Zhijian Wu

    2007-01-01

    We characterize the symbol functions so that the associated commutators with symbol functions and the Hilbert transform are bounded on Lipschitz space Apα, where 1 < p < ∞ and 0 < α < 1/P. Properties of such symbols are also discussed.

  9. Phase space quantization, non-commutativity and the gravitational field

    CERN Document Server

    Chatzistavrakidis, Athanasios

    2014-01-01

    In this paper we study the structure of the phase space in non-commutative geometry in the presence of a non-trivial frame. Our basic assumptions are that the underlying space is a symplectic and parallelizable manifold. Furthermore, we assume the validity of the Leibniz rule and the Jacobi identities. We consider non-commutative spaces due to the quantization of the symplectic structure and determine the momentum operators that guarantee a set of canonical commutation relations, appropriately extended to include the non-trivial frame. We stress the important role of left vs. right acting operators and of symplectic duality. This enables us to write down the form of the full phase space algebra on these non-commutative spaces, both in the non-compact and in the compact case. We test our results against the class of 4D and 6D symplectic nilmanifolds, thus presenting a large set of non-trivial examples that realize the general formalism.

  10. Regenerative Snubber For GTO-Commutated SCR Inverter

    Science.gov (United States)

    Rippel, Wally E.; Edwards, Dean B.

    1992-01-01

    Proposed regenerative snubbing circuit substituted for dissipative snubbing circuit in inverter based on silicon controlled rectifiers (SCR's) commutated by gate-turn-off thyristor (GTO). Intended to reduce loss of power that occurs in dissipative snubber. Principal criteria in design: low cost, simplicity, and reliability.

  11. Resident and Commuter Students: Is It Only the Living Situation?

    Science.gov (United States)

    Welty, John D.

    1976-01-01

    The impact of the residence hall and commuter living situations on a freshman's intellectual and personal growth is studied. The study affirms previous findings that residence hall freshmen develop more rapidly, but the results suggest that other college experience factors beyond the living situation are important in facilitating student…

  12. Action patterns of amylolytic enzymes as determined by the [1-14C]malto-oligosaccharide mapping method.

    Science.gov (United States)

    Pazur, J H; Marchetti, N T

    1992-04-06

    A valuable technique for oligosaccharide mapping, utilizing radioactive malto-oligosaccharides, multiple-ascent p.c., and radioautography, has been developed for identifying the action patterns of the glucoamylase isozymes, alpha-amylases, beta-amylase, glucosyltransferase, and glucanosyltransferase. The glucoamylase isozymes act by multi-chain mechanisms on malto-oligosaccharides and most likely on starch and glycogen. The alpha-amylases act endo-wise and randomly hydrolyze alpha-(1----4)- but not alpha-(1----6)-glucosidic bonds. These amylases may act by single-chain and/or multi-chain mechanisms, depending on the number of hydrolytic attacks per single encounter of the enzyme and the substrate. The beta-amylases hydrolyze malto-oligosaccharides by a multi-chain mechanism. A fungal glucosyltransferase from Aspergillus niger transfers glucose units by a single-chain mechanism from maltose to glucosyl acceptors to yield new gluco-oligosaccharides with alpha-(1----4) and alpha-(1----6) linkages. A novel type of transferase isolated from Bacillus subtilis acts by a multi-chain mechanism and transfers segments of 2 to 5 glucose residues from malto-oligosaccharides to acceptor co-substrates. An alpha-amylase from the same organism removes maltotriose units from the non-reducing ends of oligosaccharides by a multi-chain mechanism.

  13. Impacts of spatial mismatch on commuting time of urban residents in China

    Directory of Open Access Journals (Sweden)

    Danwen Bao

    2014-05-01

    Full Text Available In much of studies on spatial mismatch between residential and employer locations, job accessibility has been measured. However, the apparent disadvantages of the traditional measurement methods on the studies of Chinese cities have been noted.  This paper proposed an optimized method for job accessibility measurement by introducing the weigh coefficient of job opportunity, which quantifies the degree of uneven distribution of job opportunity in the Chinese cities. Take Nanjing city for example, this new method was used to measure the spatial distribution of job opportunity, investigate the spatial patterns and analyze the influences of job accessibility on commuting behavior. The results show that the distribution of job accessibility in Nanjing exhibits the different spatial patterns and mechanisms compared with US cases.

  14. Active commuting to school: How far is too far?

    Directory of Open Access Journals (Sweden)

    Moyna Niall M

    2008-01-01

    Full Text Available Abstract Background Walking and cycling to school provide a convenient opportunity to incorporate physical activity into an adolescent's daily routine. School proximity to residential homes has been identified as an important determinant of active commuting among children. The purpose of this study is to identify if distance is a barrier to active commuting among adolescents, and if there is a criterion distance above which adolescents choose not to walk or cycle. Methods Data was collected in 2003–05 from a cross-sectional cohort of 15–17 yr old adolescents in 61 post primary schools in Ireland. Participants self-reported distance, mode of transport to school and barriers to active commuting. Trained researchers took physical measurements of height and weight. The relation between mode of transport, gender and population density was examined. Distance was entered into a bivariate logistic regression model to predict mode choice, controlling for gender, population density socio-economic status and school clusters. Results Of the 4013 adolescents who participated (48.1% female, mean age 16.02 ± 0.661, one third walked or cycled to school. A higher proportion of males than females commuted actively (41.0 vs. 33.8%, χ2 (1 = 22.21, p 2 (df = 3 = 839.64, p 2 (df = 1 = 2591.86, p Conclusion Distance is an important perceived barrier to active commuting and a predictor of mode choice among adolescents. Distances within 2.5 miles are achievable for adolescent walkers and cyclists. Alternative strategies for increasing physical activity are required for individuals living outside of this criterion.

  15. Epidemic Process over the Commute Network in a Metropolitan Area

    Science.gov (United States)

    Yashima, Kenta; Sasaki, Akira

    2014-01-01

    An understanding of epidemiological dynamics is important for prevention and control of epidemic outbreaks. However, previous studies tend to focus only on specific areas, indicating that application to another area or intervention strategy requires a similar time-consuming simulation. Here, we study the epidemic dynamics of the disease-spread over a commute network, using the Tokyo metropolitan area as an example, in an attempt to elucidate the general properties of epidemic spread over a commute network that could be used for a prediction in any metropolitan area. The model is formulated on the basis of a metapopulation network in which local populations are interconnected by actual commuter flows in the Tokyo metropolitan area and the spread of infection is simulated by an individual-based model. We find that the probability of a global epidemic as well as the final epidemic sizes in both global and local populations, the timing of the epidemic peak, and the time at which the epidemic reaches a local population are mainly determined by the joint distribution of the local population sizes connected by the commuter flows, but are insensitive to geographical or topological structure of the network. Moreover, there is a strong relation between the population size and the time that the epidemic reaches this local population and we are able to determine the reason for this relation as well as its dependence on the commute network structure and epidemic parameters. This study shows that the model based on the connection between the population size classes is sufficient to predict both global and local epidemic dynamics in metropolitan area. Moreover, the clear relation of the time taken by the epidemic to reach each local population can be used as a novel measure for intervention; this enables efficient intervention strategies in each local population prior to the actual arrival. PMID:24905831

  16. A new non-commutative representation of the Wiener and Poisson processes; Une nouvelle representation non-commutative du mouvement brownien et du processus de Poisson

    Energy Technology Data Exchange (ETDEWEB)

    Privault, N. [Universite d`Evry, 91 (France)

    1996-05-20

    Using two different constructions of the chaotic and variational calculus on Poisson space, we show that the Wiener and Poisson processes have a non-commutative representation which is different from the one obtained by transfer of the Fock space creation and annihilation operators. We obtain in this way an extension of the non-commutative It calculus. The associated commutation relations show a link between the geometric and exponential distributions. (author). 11 refs.

  17. Factorization of stochastic maps using the Stinespring representations

    OpenAIRE

    2016-01-01

    In this work, we investigate the existence of a factorization for a unital completely positive map, between non-commutative probability space which do not change the expectation values of the events. These maps are called in literature stochastic maps. Using the Stinespring representations of completely positive map and assuming the existence of anti-unitary operator on Hilbert space related to these representations which satisfying some modular relations, we prove that stochastic maps with a...

  18. LAMB SHIFT IN HYDROGEN-LIKE ATOM INDUCED FROM NON-COMMUTATIVE QUANTUM SPACE-TIME

    Directory of Open Access Journals (Sweden)

    S Zaim

    2015-06-01

    Full Text Available In this work we present an important contribution to the non-commutative approach to the hydrogen atom to deal with lamb shift corrections. This can be done by studying the Klein-Gordon equation in a non-commutative space-time as applied to the Hydrogen atom to extract the energy levels, by considering the second-order corrections in the non commutativity parameter and by comparing with the result of the current experimental results on the Lamb shift of the 2P level to extract a bound on the parameter of non-commutativity. Phenomenologically we show that the non-commutativity effects induce lamb shift corrections.

  19. Association Between User-Generated Commuting Data and Population-Representative Active Commuting Surveillance Data - Four Cities, 2014-2015.

    Science.gov (United States)

    Whitfield, Geoffrey P; Ussery, Emily N; Riordan, Brian; Wendel, Arthur M

    2016-09-16

    Creating environments that support all types of physical activity, including active transportation, is a public health priority (1). Public health surveillance that identifies the locations where community members walk and bicycle (i.e., engage in active transportation) can inform such efforts. Traditional population-representative active transportation surveillance incurs a considerable time lag between data collection and dissemination, and often lacks geographic specificity (2). Conversely, user-generated active transportation data from Global Positioning System (GPS)-based activity tracking devices and mobile applications can provide near real-time information, but might be subject to self-selection bias among users. CDC analyzed the association between GPS-based commuting data from a company that allows tracking of activity with a mobile application (Strava, Inc., San Francisco, California) and population-representative commuting data from the U.S. Census Bureau's American Community Survey (ACS) (3) for four U.S. cities. The level of analysis was the Census block group. The number of GPS-tracked commuters in Strava was associated with the number of ACS active commuters (Spearman's rho = 0.60), suggesting block groups were ranked similarly based on these distinct but related measurements. The correlation was higher in high population density areas. User-generated active transportation data might complement traditional surveillance systems by providing near real-time, location-specific information on where active transportation occurs.

  20. The equationally-defined commutator a study in equational logic and algebra

    CERN Document Server

    Czelakowski, Janusz

    2015-01-01

    This monograph introduces and explores the notions of a commutator equation and the equationally-defined commutator from the perspective of abstract algebraic logic.  An account of the commutator operation associated with equational deductive systems is presented, with an emphasis placed on logical aspects of the commutator for equational systems determined by quasivarieties of algebras.  The author discusses the general properties of the equationally-defined commutator, various centralization relations for relative congruences, the additivity and correspondence properties of the equationally-defined commutator, and its behavior in finitely generated quasivarieties. Presenting new and original research not yet considered in the mathematical literature, The Equationally-Defined Commutator will be of interest to professional algebraists and logicians, as well as graduate students and other researchers interested in problems of modern algebraic logic.

  1. Commuting behaviour and urban form: a longitudinal study of a polycentric urban region in Denmark

    DEFF Research Database (Denmark)

    Grunfelder, Julien; Nielsen, Thomas Alexander Sick

    2012-01-01

    This paper is an empirical investigation of the relation between urban form and commuting behaviour in a polycentric urban region. It explores to what extent urban form and location variables help to explain commuting time, distance and mode based on an empirical case, East Jutland, which...... is a polycentric urban region in Denmark. Data from the National Transport Survey of Denmark were used for this quantitative analysis and two time periods were selected to highlight any potential changes over time. Empirical findings indicate that urban form and location variables help to explain the three...... selected aspects of commuting. However, urban form variables have greater explanatory power in explaining commuting modes than commuting time and commuting distance. No general trends in commuting were detectable from the data. Finally, the empirical findings revealed specificities of the case study...

  2. Temperature micro-mapping and redox conditions of a chlorite zoning pattern in green-schist facies fault zone

    Science.gov (United States)

    Trincal, Vincent; Lanari, Pierre; Lacroix, Brice; Buatier, Martine D.; Charpentier, Delphine; Labaume, Pierre; Muñoz, Manuel

    2014-05-01

    Faults are major discontinuities driving fluid flows and playing a major role in precipitation of ore deposits. Mineral paragenesis and crystal chemistry depend on Temperature (T) condition, fluid composition but also on the redox environment of precipitation. The studied samples come from the Pic de Port Vieux thrust sheet, a minor thrust sheet associated to Gavarnie thrust fault zone (Central Pyrenees). The Pic de Port Vieux Thrust sheet comprises a 1-20 meter thick layer of Triassic red beds and mylonitized Cretaceous limestone. The thrust sheet is affected by faults and cleavage; the other important deformation product is a set of veins filled by quartz and chlorite. Microstructural and mineralogical investigations were performed based on the previous work of Grant (1992). The crystallization of chlorite is syn-tectonic and strongly controlled by the fluid circulation during the Gavarnie thrust sheet emplacement. Chlorite precipitated in extension veins, crack-seal shear veins or in open cavities. The chlorite filling the open cavities occurs as pseudo-uniaxial plates arranged in rosette-shaped aggregates. These aggregates appear to have developed as a result of radial growth of the chlorite platelets. According to point and microprobe X-ray images, these chlorites display oscillatory chemical zoning patterns with alternating iron rich and magnesium rich bands. The chlorite composition ranges from Fe rich pole (Si2.62Al1.38O10(Al1.47Fe1.87Mg2.61)6(OH)8) to Mg rich pole (Si2.68Al1.31O10(Al1.45Fe1.41Mg3.06)6(OH)8). In metamorphic rocks, zoning pattern or rimmed minerals results for varying P or T conditions and can be used to unravel the P-T history of the sample. In the present study, temperature maps are derived from standardized microprobe X-ray images using the program XMapTools (Lanari et al 2014). The (Fe3+/Fetot) value in chlorite was directly measured using μXANES spot analyses collected at the Fe-K edge. The results indicate a homogeneous temperature of

  3. Mapping present and future potential distribution patterns for a meso-grazer guild in the Baltic Sea.

    Science.gov (United States)

    Leidenberger, Sonja; De Giovanni, Renato; Kulawik, Robert; Williams, Alan R; Bourlat, Sarah J; Maggs, Christine

    2015-02-01

    The Baltic Sea is one of the world's largest semi-enclosed brackish water bodies characterized by many special features, including endemic species that may be particularly threatened by climate change. We mapped potential distribution patterns under present and future conditions for a community with three trophic levels. We analysed climate-induced changes in the species' distribution patterns and examined possible consequences for the chosen food web. Baltic Sea and northern Europe. We developed two open-source workflow-based analytical tools: one for ecological niche modelling and another for raster layer comparison to compute the extent and intensity of change in species' potential distributions. Individual ecological niche models were generated under present conditions and then projected into a future climate change scenario (2050) for a food web consisting of a guild of meso-grazers (Idotea spp.), their host algae (Fucus vesiculosus and Fucus radicans) and their fish predator (Gasterosteus aculeatus). We used occurrence data from the Global Biodiversity Information Facility (GBIF), literature and museum collections, together with five environmental layers at a resolution of 5 and 30 arc-minutes. Habitat suitability for Idotea balthica and Idotea chelipes in the Baltic Sea seems to be mostly determined by temperature and ice cover rather than by salinity. 2050 predictions for all modelled species show a northern/north-eastern shift in the Baltic Sea. The distribution ranges for Idotea granulosa and G. aculeatus are predicted to become patchier in the Baltic than in the rest of northern Europe, where the species will gain more suitable habitats. For the Baltic Sea, climate-induced changes resulted in a gain of suitable habitats for F. vesiculosus,I. chelipes and I. balthica, whereas lower habitat suitability was predicted for I. granulosa,F. radicans and G. aculeatus. The predicted north-eastern shift of I. balthica and I. chelipes into the distribution area of

  4. Mapping present and future potential distribution patterns for a meso-grazer guild in the Baltic Sea

    Science.gov (United States)

    Leidenberger, Sonja; De Giovanni, Renato; Kulawik, Robert; Williams, Alan R; Bourlat, Sarah J; Maggs, Christine

    2015-01-01

    Aim The Baltic Sea is one of the world's largest semi-enclosed brackish water bodies characterized by many special features, including endemic species that may be particularly threatened by climate change. We mapped potential distribution patterns under present and future conditions for a community with three trophic levels. We analysed climate-induced changes in the species' distribution patterns and examined possible consequences for the chosen food web. Location Baltic Sea and northern Europe. Methods We developed two open-source workflow-based analytical tools: one for ecological niche modelling and another for raster layer comparison to compute the extent and intensity of change in species' potential distributions. Individual ecological niche models were generated under present conditions and then projected into a future climate change scenario (2050) for a food web consisting of a guild of meso-grazers (Idotea spp.), their host algae (Fucus vesiculosus and Fucus radicans) and their fish predator (Gasterosteus aculeatus). We used occurrence data from the Global Biodiversity Information Facility (GBIF), literature and museum collections, together with five environmental layers at a resolution of 5 and 30 arc-minutes. Results Habitat suitability for Idotea balthica and Idotea chelipes in the Baltic Sea seems to be mostly determined by temperature and ice cover rather than by salinity. 2050 predictions for all modelled species show a northern/north-eastern shift in the Baltic Sea. The distribution ranges for Idotea granulosa and G. aculeatus are predicted to become patchier in the Baltic than in the rest of northern Europe, where the species will gain more suitable habitats. Main conclusions For the Baltic Sea, climate-induced changes resulted in a gain of suitable habitats for F. vesiculosus,I. chelipes and I. balthica, whereas lower habitat suitability was predicted for I. granulosa,F. radicans and G. aculeatus. The predicted north-eastern shift of I. balthica

  5. Mapping spatial patterns of stream power and channel change along a gravel-bed river in northern Yellowstone

    Science.gov (United States)

    Lea, Devin M.; Legleiter, Carl J.

    2016-01-01

    Stream power represents the rate of energy expenditure along a river and can be calculated using topographic data acquired via remote sensing or field surveys. This study sought to quantitatively relate temporal changes in the form of Soda Butte Creek, a gravel-bed river in northeastern Yellowstone National Park, to stream power gradients along an 8-km reach. Aerial photographs from 1994 to 2012 and ground-based surveys were used to develop a locational probability map and morphologic sediment budget to assess lateral channel mobility and changes in net sediment flux. A drainage area-to-discharge relationship and DEM developed from LiDAR data were used to obtain the discharge and slope values needed to calculate stream power. Local and lagged relationships between mean stream power gradient at median peak discharge and volumes of erosion, deposition, and net sediment flux were quantified via spatial cross-correlation analyses. Similarly, autocorrelations of locational probabilities and sediment fluxes were used to examine spatial patterns of sediment sources and sinks. Energy expended above critical stream power was calculated for each time period to relate the magnitude and duration of peak flows to the total volumetric change in each time increment. Collectively, we refer to these methods as the stream power gradient (SPG) framework. The results of this study were compromised by methodological limitations of the SPG framework and revealed some complications likely to arise when applying this framework to small, wandering, gravel-bed rivers. Correlations between stream power gradients and sediment flux were generally weak, highlighting the inability of relatively simple statistical approaches to link sub-budget cell-scale sediment dynamics to larger-scale driving forces such as stream power gradients. Improving the moderate spatial resolution techniques used in this study and acquiring very-high resolution data from recently developed methods in fluvial remote

  6. Probability mapping to determine the spatial risk pattern of acute gastroenteritis in Coimbatore District, India, using Geographic Information Systems (GIS

    Directory of Open Access Journals (Sweden)

    Pawlin Vasanthi Joseph

    2015-01-01

    Full Text Available Background: Maps show well the spatial configuration of information. Considerable effort is devoted to the development of geographical information systems (GIS that increase understanding of public health problems and in particular to collaborate efforts among clinicians, epidemiologists, ecologists, and geographers to map and forecast disease risk. Objectives: Small populations tend to give rise to the most extreme disease rates, even if the actual rates are similar across the areas. Such situations will follow the decision-maker′s attention on these areas when they scrutinize the map for decision making or resource allocation. As an alternative, maps can be prepared using P-values (probabilistic values. Materials and Methods: The statistical significance of rates rather than the rates themselves are used to map the results. The incidence rates calculated for each village from 2000 to 2009 is used to estimate λ, the expected number of cases in the study area. The obtained results are mapped using Arc GIS 10.0. Results: The likelihood of infections from low to high is depicted in the map and it is observed that five villages namely, Odanthurai, Coimbatore Corporation, Ikkaraiboluvampatti, Puliakulam, and Pollachi Corporation are more likely to have significantly high incidences. Conclusion: In the probability map, some of the areas with exceptionally high or low rates disappear. These are typically small unpopulated areas, whose rates are unstable due to the small numbers problem. The probability map shows more specific regions of relative risks and expected outcomes.

  7. Application of variable-sweep wings to commuter aircraft

    Science.gov (United States)

    Robins, A. W.; Beissner, F. L., Jr.; Lovell, W. A.; Price, J. E.; Turriiziani, R. V.; Washburn, F. F.

    1983-01-01

    The effects of using variable-sweep wings on the riding quality and mission-performance characteristics of commuter-type aircraft were studied. A fixed-wing baseline vehicle and a variable-sweep version of the baseline were designed and evaluated. Both vehicles were twin-turboprop, pressurized-cabin, 30-passenger commuter aircraft with identical mission requirements. Mission performance was calculated with and without various ride-quality constraints for several combinations of cruise altitude and stage lengths. The variable-sweep aircraft had a gross weight of almost four percent greater than the fixed-wing baseline in order to meet the design-mission requirements. In smooth air, the variable sweep configuration flying with low sweep had a two to three percent fuel-use penalty. However, the imposition of quality constraints in rough air can result in advantages in both fuel economy and flight time for the variable-sweep vehicle flying with high sweep.

  8. Incremental Commute Time Distance and Applications in Anomaly Detection Systems

    CERN Document Server

    Khoa, Nguyen Lu Dang

    2011-01-01

    Commute Time Distance (CTD) is a random walk based metric on graphs. CTD has found widespread applications in many domains including personalized search, collaborative filtering and making search engines robust against manipulation. Our interest is inspired by the use of CTD as a metric for anomaly detection. It has been shown that CTD can be used to simultaneously identify both global and local anomalies. Here we propose an accurate and efficient approximation for computing the CTD in an incremental fashion in order to facilitate real-time applications. An online anomaly detection algorithm is designed where the CTD of each new arriving data point to any point in the current graph can be estimated in constant time ensuring a real-time response. Moreover, the proposed approach can also be applied in many other applications that utilize commute time distance.

  9. Limit Algebras of Differential Forms in Non-Commutative Geometry

    Indian Academy of Sciences (India)

    S J Bhatt; A Inoue

    2008-08-01

    Given a C∗-normed algebra A which is either a Banach ∗-algebra or a Frechet ∗-algebra, we study the algebras ∞A and A obtained by taking respectively the projective limit and the inductive limit of Banach ∗-algebras obtained by completing the universal graded differential algebra ∗A of abstract non-commutative differential forms over A. Various quantized integrals on ∞A induced by a K-cycle on A are considered. The GNS-representation of ∞A defined by a d-dimensional non-commutative volume integral on a d+-summable K-cycle on A is realized as the representation induced by the left action of A on ∗A. This supplements the representation A on the space of forms discussed by Connes (Ch. VI.1, Prop. 5, p. 550 of [C]).

  10. Functional approach to squeezed states in non commutative theories

    CERN Document Server

    Lubo, M

    2004-01-01

    We review some noncommutative theories in which no state saturates simultaneously all the non trivial Heisenberg uncertainty relations. We show how the difference of structure between the Poisson brackets and the commutators in these theories generically leads to a harmonic oscillator whose position mean value is not strictly equal to the one predicted by classical mechanics. This raises the question of the nature of quasi classical states in these models. We propose an extension based on a variational principle. The action considered is the sum of the squares of the terms associated to the non trivial Heisenberg uncertainty relations. We first verify that our proposal works in the usual theory: we recover the known gaussian functions and, besides them, other states which can be expressed as products of gaussians with specific hypergeometrics. We illustrate our construction in three models defined on a four dimensional phase space: two models endowed with a minimal length uncertainty and the non commutative p...

  11. Jónsson and HS Modules over Commutative Rings

    Directory of Open Access Journals (Sweden)

    Greg Oman

    2014-01-01

    Full Text Available Let R be a commutative ring with identity and let M be an infinite unitary R-module. (Unless indicated otherwise, all rings are commutative with identity 1≠0 and all modules are unitary. Then M is called a Jónsson module provided every proper submodule of M has smaller cardinality than M. Dually, M is said to be homomorphically smaller (HS for short if |M/N|<|M| for every nonzero submodule N of M. In this survey paper, we bring the reader up to speed on current research on these structures by presenting the principal results on Jónsson and HS modules. We conclude the paper with several open problems.

  12. Categories of Representations of a Class of Commutative Cancellative Semigroups

    Institute of Scientific and Technical Information of China (English)

    Antonio M. Cegarra; Mario Petrich

    2001-01-01

    A commutative semigroup S is subarchimedean if there exists z ∈ S such that for any a ∈ S, there are n > 0 and x ∈ S such that zn = ax. A commutative cancellative idempotent-free subarchimedean semigroup is a -semigroup.These semigroups admit Tamura-like representations of the form N(G, I) and N(G,ψ), and their groups of quotients Z(G, I) and Z(G, ψ). We consider categories whose objects are of the form (G, I; N), (G, ψ; N), (G, I; Z), and (G, ψ; Z)with suitable morphisms, and establish functorial relationships among these categories as well as with the categories of -semigroups and non-periodic abelian groups.

  13. Macdonald polynomials in superspace as eigenfunctions of commuting operators

    CERN Document Server

    Blondeau-Fournier, O; Lapointe, L; Mathieu, P

    2012-01-01

    A generalization of the Macdonald polynomials depending upon both commuting and anticommuting variables has been introduced recently. The construction relies on certain orthogonality and triangularity relations. Although many superpolynomials were constructed as solutions of highly over-determined system, the existence issue was left open. This is resolved here: we demonstrate that the underlying construction has a (unique) solution. The proof uses, as a starting point, the definition of the Macdonald superpolynomials in terms of the Macdonald non-symmetric polynomials via a non-standard (anti)symmetrization and a suitable dressing by anticommuting monomials. This relationship naturally suggests the form of two family of commuting operators that have the defined superpolynomials as their common eigenfunctions. These eigenfunctions are then shown to be triangular and orthogonal. Up to a normalization, these two conditions uniquely characterize these superpolynomials. Moreover, the Macdonald superpolynomials ar...

  14. Quantized equations of motion in non-commutative theories

    CERN Document Server

    Heslop, P; Heslop, Paul; Sibold, Klaus

    2004-01-01

    Quantum field theories based on interactions which contain the Moyal star product suffer, in the general case when time does not commute with space, from several diseases: quantum equation of motions contain unusual terms, conserved currents can not be defined and the residual spacetime symmetry is not maintained. All these problems have the same origin: time ordering does not commute with taking the star product. Here we show that these difficulties can be circumvented by a new definition of time ordering: namely with respect to a light-cone variable. In particular the original spacetime symmetries SO(1,1) x SO(2) and translation invariance turn out to be respected. Unitarity is guaranteed as well.

  15. Teaching Quantum Mechanical Commutation Relations via an Optical Experiment

    CERN Document Server

    Billur, A Alper; Bursal, Murat

    2015-01-01

    The quantum mechanical commutation relations, which are directly related to the Heisenberg uncertainty principle, have a crucial importance for understanding the quantum mechanics of students. During undergraduate level courses, the operator formalisms are generally given theoretically and it is documented that these abstract formalisms are usually misunderstood by the students. Based on the idea that quantum mechanical phenomena can be investigated via geometric optical tools, this study aims to introduce an experiment, where the quantum mechanical commutation relations are represented in a concrete way to provide students an easy and permanent learning. The experimental tools are chosen to be easily accessible and economic. The experiment introduced in this paper can be done with students or used as a demonstrative experiment in laboratory based or theory based courses requiring quantum physics content; particularly in physics, physics education and science education programs.

  16. Canonical approach to the closed string non-commutativity

    Energy Technology Data Exchange (ETDEWEB)

    Davidovic, Lj.; Nikolic, B.; Sazdovic, B. [University of Belgrade, Institute of Physics, P.O.Box 57, Belgrade (Serbia)

    2014-01-15

    We consider the closed stringmoving in a weakly curved background and its totally T-dualized background. Using T-duality transformation laws, we find the structure of the Poisson brackets in the T-dual space corresponding to the fundamental Poisson brackets in the original theory. From this structure we see that the commutative original theory is equivalent to the non-commutative T-dual theory, whose Poisson brackets are proportional to the background fluxes times winding and momentum numbers. The noncommutative theory of the present article is more nongeometrical than T-folds and in the case of three space-time dimensions corresponds to the nongeometric space-time with R-flux. (orig.)

  17. A commuting generation model requiring only aggregated data

    CERN Document Server

    Lenormand, Maxime; Gargiulo, Floriana

    2011-01-01

    We recently proposed, in (Gargiulo et al., 2011), an innova tive stochastic model with only one parameter to calibrate. It reproduces the complete network by an iterative process stochastically choosing, for each commuter living in the municipality of a region, a workplace in the region. The choice is done considering the job offer in each municipality of the region and the distance to all the possible destinations. The model is quite effective if the region is sufficiently autonomous in terms of job offers. However, calibrating or being sure of this autonomy require data or expertise which are not necessarily available. Moreover the region can be not autonomous. In the present, we overcome these limitations, extending the job search geographical base of the commuters to the outside of the region, and changing the deterrence function form. We also found a law to calibrate the improvement model which does not require data.

  18. A norm inequality for pairs of commuting positive semidefinite matrices

    OpenAIRE

    Audenaert, Koenraad M. R.

    2014-01-01

    For $k=1,\\ldots,K$, let $A_k$ and $B_k$ be positive semidefinite matrices such that, for each $k$, $A_k$ commutes with $B_k$. We show that, for any unitarily invariant norm, \\[ |||\\sum_{k=1}^K A_kB_k||| \\le ||| (\\sum_{k=1}^K A_k)\\;(\\sum_{k=1}^K B_k)|||. \\

  19. New QCD sum rules based on canonical commutation relations

    Science.gov (United States)

    Hayata, Tomoya

    2012-04-01

    New derivation of QCD sum rules by canonical commutators is developed. It is the simple and straightforward generalization of Thomas-Reiche-Kuhn sum rule on the basis of Kugo-Ojima operator formalism of a non-abelian gauge theory and a suitable subtraction of UV divergences. By applying the method to the vector and axial vector current in QCD, the exact Weinberg’s sum rules are examined. Vector current sum rules and new fractional power sum rules are also discussed.

  20. AC system stabilization via phase shift transformer with thyristor commutation

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Jose Carlos de; Guimaraes, Geraldo Caixeta; Moraes, Adelio Jose [Uberlandia Univ., MG (Brazil); Abreu, Jose Policarpo G. de [Escola Federal de Engenharia de Itajuba, MG (Brazil); Oliveira, Edimar Jose de [Juiz de Fora Univ., MG (Brazil)

    1994-12-31

    This article aims to present initially the constructive and operative forms of a phase-shift autotransformer which provides both magnitude and phase angle change through thyristor commutation, including a technic to reduce the number of thyristors. Following, it is proposed a control system to make such equipment an efficient AC system stabilizing tool. It is presented some simulation results to show the operation of this transformer in an electrical system. (author) 3 refs., 11 figs., 3 tabs.

  1. Derivations, Products of Derivations, and Commutativity in Near-rings

    Institute of Scientific and Technical Information of China (English)

    Howard E. Bell; Nurcan Argac

    2001-01-01

    For a zero-symmetric 3-prime near-ring N, we study three kinds of conditions: (a) conditions involving two derivations d1, d2 which imply that d1 = 0 or d2 = 0; (b) conditions involving derivations which force (N, +) to be abelian or N to be a commutative ring; (c) the condition that dn (S) is multiplicatively central for some derivation d and subset S of N.

  2. Commutator-based linearization of $N = 1$ nonlinear supersymmetry

    CERN Document Server

    Tsuda, Motomu

    2016-01-01

    We consider the linearization of $N = 1$ nonlinear supersymmetry (NLSUSY) based on a commutator algebra in Volkov-Akulov NLSUSY theory. We show explicitly that $U(1)$ gauge and scalar supermultiplets in addition to a vector supermultiplet with general auxiliary fields in linear SUSY theories are obtained from a same set of bosonic and fermionic functionals (composites) which are expressed as simple products of the powers of a Nambu-Goldstone fermion and a fundamental determinant in the NLSUSY theory.

  3. Rotation of D-brane and Non-commutative Geometry

    CERN Document Server

    Wang, P; Wang, Pei; Yue, Ruihong

    1999-01-01

    Our motivation is to find the relationship between the commutator of coordinates and uncertainty relation involving only the coordinates. The boundary condition with constant background field is connected with the rotation of D-brane at general angle. And the mode expansions of D-brane we found is more reasonable than those appeared in literature. The partition functions and scattering amplitudes are also discussed.

  4. Study of high current commutation by explosive switch

    Science.gov (United States)

    Usuba, S.; Kakudate, Y.; Yoshida, M.; Fujiwara, S.; Miyamoto, M.; Morita, T.; Kubota, A.; den, M.

    1993-01-01

    The study presents the basic experimental data obtained with a large current opening switch for current commutation using explosives. It is shown that currents up to a maximum of 40 kA can be completely interrupted within 30 microsec. The mechanism of current interruption using a thin conductor plate and methods of measuring interrupting current with a pickup coil and taking photographs with a high-speed camera (one frame per microsec) are discussed.

  5. Quantum Mechanics: Harbinger of a Non-Commutative Probability Theory?

    OpenAIRE

    Hiley, Basil J.

    2014-01-01

    In this paper we discuss the relevance of the algebraic approach to quantum phenomena first introduced by von Neumann before he confessed to Birkoff that he no longer believed in Hilbert space. This approach is more general and allows us to see the structure of quantum processes in terms of non-commutative probability theory, a non-Boolean structure of the implicate order which contains Boolean sub-structures which accommodates the explicate classical world. We move away from mechanical `wave...

  6. Dynamics as the preservation of a constant commutator

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Vega, Gabino [Departamento de Fisica, Cinvestav, apartado postal 14-740, 07000 Mexico, Distrito Federal (Mexico)], E-mail: gabino@fis.cinvestav.mx

    2007-10-01

    Some properties involving two operators with a constant commutator are derived. They include a definition of derivatives of operator functions, their conjugate spaces, and the associated translation generators. The cases of real functions, quantum coordinate and momentum operators, time and Liouville operator, and quantum time and energy operators, are analyzed within this formalism. This procedure allows the elucidation of the properties of time in classical and quantum mechanics.

  7. Non-commutative Complex Projective Spaces and the Standard Model

    OpenAIRE

    Dolan, Brian P

    2003-01-01

    The standard model fermion spectrum, including a right handed neutrino, can be obtained as a zero-mode of the Dirac operator on a space which is the product of complex projective spaces of complex dimension two and three. The construction requires the introduction of topologically non-trivial background gauge fields. By borrowing from ideas in Connes' non-commutative geometry and making the complex spaces `fuzzy' a matrix approximation to the fuzzy space allows for three generations to emerge...

  8. Associations between active commuting and physical activity in working adults: Cross-sectional results from the Commuting and Health in Cambridge study

    Science.gov (United States)

    Yang, Lin; Panter, Jenna; Griffin, Simon J.; Ogilvie, David

    2012-01-01

    Objective To quantify the association between time spent in active commuting and in moderate to vigorous physical activity (MVPA) in a sample of working adults living in both urban and rural locations. Methods In 2009, participants in the Commuting and Health in Cambridge study were sent questionnaires enquiring about sociodemographic characteristics and weekly time spent in active commuting. They were also invited to wear an accelerometer for seven days. Accelerometer data were used to compute the time spent in MVPA. Multiple regression models were used to examine the association between time spent in active commuting and MVPA. Results 475 participants (70% female) provided valid data. On average, participants recorded 55 (SD: 23.02) minutes of MVPA per day. For women, reporting 150 or more minutes of active commuting per week was associated with an estimated 8.50 (95% CI: 1.75 to 51.26, p = 0.01) additional minutes of daily MVPA compared to those who reported no time in active commuting. No overall associations were found in men. Conclusions Promoting active commuting might be an important way of increasing levels of physical activity, particularly in women. Further research should assess whether increases in time spent in active commuting are associated with increases in physical activity. PMID:22964003

  9. An exploration of future patterns of the contributions to OpenStreetMap and development of a contribution index

    NARCIS (Netherlands)

    Jokar Arsanjani, J; Mooney, P; Helbich, M; Zipf, A

    2015-01-01

    OpenStreetMap (OSM) represents one of the most well-known examples of a collaborative mapping project. Major research efforts have so far dealt with data quality analysis but the modality of OSM's evolution across space and time has barely been noted. This study aims to analyze spatio-temporal patte

  10. On the range of completely bounded maps

    Directory of Open Access Journals (Sweden)

    Richard I. Loebl

    1978-01-01

    Full Text Available It is shown that if every bounded linear map from a C*-algebra α to a von Neumann algebra β is completely bounded, then either α is finite-dimensional or β⫅⊗Mn, where is a commutative von Neumann algebra and Mn is the algebra of n×n complex matrices.

  11. Modeling the relation between income and commuting distance

    CERN Document Server

    Carra, Giulia; Fosgerau, Mogens; Barthelemy, Marc

    2016-01-01

    We discuss the distribution of commuting distances and its relation to income. Using data from Great Britain, US and Denmark, we show that the commuting distance is (i) broadly distributed with a tail decaying typically as $1/r^\\gamma$ with $\\gamma \\approx 3$ and (ii) an average growing slowly as a power law with an exponent less than one that depends on the country considered. The classical theory for job search is based on the idea that workers evaluate potential jobs on the wage as they arrive sequentially through time. Extending this model with space, we obtain predictions that are strongly contradicted by our empirical findings. We then propose an alternative model that is based on the idea that workers evaluate potential jobs based on a quality aspect and that workers search for jobs sequentially across space. We assume that the density of potential jobs depends on the skills of the worker and decreases with the wage. The predicted distribution of commuting distances decays as $1/r^3$ and is independent...

  12. [Relationships between settlement morphology transition and residents commuting energy consumption].

    Science.gov (United States)

    Zhou, Jian; Xiao, Rong-Bo; Sun, Xiang

    2013-07-01

    Settlement morphology transition is triggered by rapid urbanization and urban expansion, but its relationships with residents commuting energy consumption remains ambiguous. It is of significance to understand the controlling mechanisms of sustainable public management policies on the energy consumption and greenhouse gases emission during the process of urban settlement morphology transition. Taking the Xiamen City of East China as a case, and by using the integrated land use and transportation modeling system TRANUS, a scenario analysis was made to study the effects of urban settlement morphology transition on the urban spatial distribution of population, jobs, and land use, and on the residents commuting energy consumption and greenhouse gasses emission under different scenarios. The results showed that under the Business As Usual (BAU) scenario, the energy consumption of the residents at the morning peak travel time was 54.35 tce, and the CO2 emission was 119.12 t. As compared with those under BAU scenario, both the energy consumption and the CO2 emission under the Transition of Settlement Morphology (TSM) scenario increased by 12%, and, with the implementation of the appropriate policies such as land use, transportation, and economy, the energy consumption and CO2 emission under the Transition of Settlement Morphology with Policies (TSMP) scenario reduced by 7%, indicating that urban public management policies could effectively control the growth of residents commuting energy consumption and greenhouse gases emission during the period of urban settlement morphology transition.

  13. Take part in the Commute-Another-Way Challenge!

    CERN Multimedia

    CERN Bulletin

    2015-01-01

    Ring the changes on Thursday, 4 June by commuting another way! CERN has signed up for the 5th “challenge mobilité Rhône-Alpes”, the aim of which is to encourage people to use modes of transport other than their car to get to work. Are you up for the challenge?   Join in the challenge! Sign up using the dedicated CERN form. "Commute another way!" is an initiative launched by the Rhône-Alpes regional authorities and the French environment agency ADEME (l’Agence de l’environnement et de la maîtrise de l’énergie française) to promote alternative ways of travelling to work than the car (excluding carpooling), in private and public-sector organisations across the region. We love this idea and CERN has been signed up to a similar scheme - Bike to Work - for several years. That’s why we’ve decided that CERN should join the Commute-A...

  14. On the commutativity degree in finite Moufang loops

    Directory of Open Access Journals (Sweden)

    Karim Ahmadidelir

    2016-09-01

    Full Text Available The textit{commutativity degree}, $Pr(G$, of a finite group $G$ (i.e. the probability that two (randomly chosen elements of $G$ commute with respect to its operation has been studied well by many authors. It is well-known that the best upper bound for $Pr(G$ is $frac{5}{8}$ for a finite non--abelian group $G$.In this paper, we will define the same concept for a finite non--abelian textit{Moufang loop} $M$ and try to give a best upper bound for $Pr(M$. We will prove that for a well-known class of finite Moufang loops, named textit{Chein loops}, and its modifications, this best upper bound is $frac{23}{32}$. So, our conjecture is that for any finite Moufang loop $M$, $Pr(Mleq frac{23}{32}$.Also, we will obtain some results related to the $Pr(M$ and ask the similar questions raised and answered in group theory about the relations between the structure of a finite group and its commutativity degree in finite Moufang loops.

  15. Non-topological non-commutativity in string theory

    Energy Technology Data Exchange (ETDEWEB)

    Guttenberg, S. [NCSR Demokritos, INP, Patriarchou Gregoriou and Neapoleos Str., 15310 Agia Paraskevi Attikis (Greece); Herbst, M. [CERN, 1211 Geneva 23 (Switzerland); Kreuzer, M. [Institute for Theoretical Physics, TU Wien, Wiedner Hauptstr. 8-10, 1040 Vienna (Austria); Rashkov, R. [Erwin Schroedinger Institute for Mathematical Physics, Boltzmanngasse 9, 1090 Vienna (Austria)

    2008-04-15

    Quantization of coordinates leads to the non-commutative product of deformation quantization, but is also at the roots of string theory, for which space-time coordinates become the dynamical fields of a two-dimensional conformal quantum field theory. Appositely, open string diagrams provided the inspiration for Kontsevich's solution of the long-standing problem of quantization of Poisson geometry by virtue of his formality theorem. In the context of D-brane physics non-commutativity is not limited, however, to the topological sector. We show that non-commutative effective actions still make sense when associativity is lost and establish a generalized Connes-Flato-Sternheimer condition through second order in a derivative expansion. The measure in general curved backgrounds is naturally provided by the Born-Infeld action and reduces to the symplectic measure in the topological limit, but remains non-singular even for degenerate Poisson structures. Analogous superspace deformations by RR-fields are also discussed. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  16. Geochemical Patterns Classification of recent Mt. Etna Volcanic Products based on a synopsis of Kohonen Maps and Fuzzy Clustering.

    Science.gov (United States)

    Corsaro, Rosa Anna; Falsaperla, Susanna; Langer, Horst

    2010-05-01

    During the last two decades Mt. Etna experienced many summit and flank eruptions with different styles of activity, ranging from quiet lava effusion to explosive activity consisting of Strombolian explosions and/or spectacular fire fountains. This complex picture entails the presence of a complex plumbing system where magma dynamics strongly controls both the eruptive style and magma differentiation. All these eruptive events have furnished volcanic products on which systematic petrographic and geochemical analyses have been carried out since the mid 1990s. In particular, the content of major and trace elements of lavas is a key-point to characterize the composition of a magma emitted during an eruption. Petrologic investigations are traditionally based on the interpretation of compositional patterns described by selected oxides and/or elements in binary and ternary petrologic systems. This kind of analysis provides useful information about the magmatic processes occurring in the plumbing system. In this presentation we investigate whether the quality of petrologic investigations is improved by the application of more sophisticated analytical techniques based on the use of a relatively large number of parameters. To this purpose, we selected 13 components, i.e., SiO2, K2O, CaO/Al2O3, Mg#, Th, La, Nb, Nd, Sr, Tb, Cr, Ni and Rb/Nb. This choice brings along the problem of designing a suitable statistics and a convenient visualization of the results. As a way out, we propose advanced concepts of multivariate classification based on a synopsis of Kohonen Maps and Fuzzy Clustering, and apply them to the study of volcanics erupted from Mt. Etna between 1995 and 2005. Lavas erupted during the fire fountains (in 2000) and during the flank eruptions (2001, 2002-03) represent the most primitive products erupted from Mt. Etna in the investigated period. The literature data suggest that during the 2001 and 2002-03 eruptions two magmas with different geochemical characteristics

  17. Patterning of impoundment impact on chironomid assemblages and their environment with use of the self-organizing map (SOM)

    Science.gov (United States)

    Penczak, Tadeusz; Kruk, Andrzej; Grzybkowska, Maria; Dukowska, Małgorzata

    2006-11-01

    The paper assesses the impact of the Jeziorsko dam reservoir on chironomid assemblages and selected environmental factors in the Warta River, Poland, by means of patterns recognized with the self-organizing map (SOM, Kohonen unsupervised artificial neural network). Over 1988-1996, in four annual cycles, a total of 233 monthly samples were collected in a seven order section of the river at two sites: WAA (backwater) located about 2 km upstream from the Jeziorsko Reservoir, and WAB (tailwater) located about 1.5 km downstream from the reservoir's dam. At each site three habitats were selected: H 1, H 2 and H 3 at WAA, and H 11, H 12 and H 13 at WAB. H 1 and H 11 were located in the depositional area close to the banks, H 2 and H 12 about 6-7 m towards the mid-river and H 3 and H 13 in the mid-river. SOM effectively vertically separated H 1 and H 11 (bank habitats) from H 3 and H 13 (the mid-river zone of both sites) and H 2 (the transition zone of the upstream site). The H 12 samples were scattered all over SOM but still exhibited a slight temporal gradient. At the end of the study the water discharge, especially in summers, stabilized at WAB at a level lower than natural and as a result submerged macrophytes appeared at H 12 making the abundance of macroinvertebrates increase very quickly. Moreover, a weaker horizontal grouping of samples by season and by site of collection (upstream or downstream from the reservoir) was observed over SOM: 1) bank upstream habitat H 1, with hydrological regime resembling natural, was separated from the downstream H 11, which enlarged and contracted in response to dam operation, 2) deeper habitats were less dependent on water level and this is why they underwent seasonal fluctuations. To sum up, the deepest habitats were most resistant to water level fluctuations, while the formerly most productive habitat at the tailwater WAB site, H 11, became the most negatively impacted. Nevertheless, the reservoir has not negatively influenced

  18. The spatial distribution of commuting CO2 emissions and the influential factors:A case study in Xi'an, China

    Institute of Scientific and Technical Information of China (English)

    LIU Yuan-Yuan; WANG Yuan-Qing; AN Rui; LI Chao

    2015-01-01

    As the transport sector is a major source of greenhouse gas emissions, the effect of urbanization on transport CO2 emissions in developing cities has become a key issue under global climate change. Examining the case of Xi'an, this paper aims to explore the spatial distribution of commuting CO2 emissions and influencing factors in the new, urban industry zones and city centers considering Xi'an's transition from a monocentric to a polycentric city in the process of urbanization. Based on household survey data from 1501 respondents, there are obvious differences in commuting CO2 emissions between new industry zones and city centers: City centers feature lower household emissions of 2.86 kg CO2 per week, whereas new industry zones generally have higher household emissions of 3.20 kg CO2 per week. Contrary to previous research results, not all new industry zones have high levels of CO2 emissions;with the rapid development of various types of industries, even a minimum level of household emissions of 2.53 kg CO2 per week is possible. The uneven distribution of commuting CO2 emissions is not uniformly affected by spatial parameters such as jobehousing balance, residential density, employment density, and land use diversity. Optimum combination of the spatial parameters and travel pattern along with corresponding transport infrastructure construction may be an appropriate path to reduction and control of emissions from commuting.

  19. Analysis of Commutation Torque Ripple Minimization for Brushless DC Motor Based on SEPIC Converter

    Directory of Open Access Journals (Sweden)

    R.Jogarao

    2016-11-01

    Full Text Available Brushless DC Motors (BLDCM are widely used in automated industrial applications like Computer Numerical Control (CNC machinery, aerospace applications and in the field of robotics.But it still suffers from commutation torque which mainly depends on speed and transient line commutation interval. BLDC MOTOR torque ripple causes increased acoustic noise and undesirable speed fluctuation. This paper presents a new circuit topology and dc link voltage current in the control strategy to keep incoming and outgoing phase currents changing at the same rate during commutation. In this paper dc-dc single ended primary inductor converter (SEPIC a switch selection circuit are employed in front of inverter. In order to obtain the desired commutation voltage resulting in reduced commutation torque ripple. Compared with simulation result conventional system and proposed method can obtain desired voltage much faster and minimize commutation torque ripple more efficiently.

  20. A Study on the Influence of Commutation Time on Torque Pulsating in BLDCM

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Choel Ju; Kang, Byoung Hee; Mok, Hyoung Su; Choe, Gyu-Ha [Konkuk University, Seoul(Korea)

    2001-01-01

    A BLDC motor has a serious drawback that torque pulsation is generated in every commutation period though it has many advantages compared to the conventional DC Motor. In this paper, the influence of commutation time on torque pulsation is studied. Generally in calculating the torque of BLDC motor, it is assumed that the decaying phase back EMF is constant, but the torque model considering decaying phase back EMF is introduced here. Through it, the torque in commutation period has torque pulsation component caused by commutation itself and it cannot be removed perfectly even if there is no current and pulsation. To reduce the torque pulsation, a new method is proposed, which controls a point of commutation and the optimal point of commutation is found. Simulation shows proposed method reduces the torque pulsation considerately. (author). 5 refs., 8 figs., 2 tabs.

  1. Automated pattern recognition to support geological mapping and exploration target generation: a case study from southern Namibia

    CSIR Research Space (South Africa)

    Eberle, D

    2015-06-01

    Full Text Available This paper demonstrates a methodology for the automatic joint interpretation of high resolution airborne geophysical and space-borne remote sensing data to support geological mapping in a largely automated, fast and objective manner. At the request...

  2. Non-commutative U(1) Gauge Theory on R**4 with Oscillator Term

    CERN Document Server

    Blaschke, Daniel N; Schweda, Manfred

    2007-01-01

    Inspired by the renormalizability of the non-commutative $\\Phi^4$ model with added oscillator term, we formulate a non-commutative gauge theory, where the oscillator enters as a gauge fixing term. All propagators turn out to be essentially given by the Mehler kernel and the bilinear part of the action is invariant under the Langmann-Szabo duality. The model is a promising candidate for a renormalizable non-commutative U(1) gauge theory.

  3. Active Commuting: Workplace Health Promotion for Improved Employee Well-Being and Organizational Behavior.

    Science.gov (United States)

    Page, Nadine C; Nilsson, Viktor O

    2016-01-01

    Objective: This paper describes a behavior change intervention that encourages active commuting using electrically assisted bikes (e-bikes) for health promotion in the workplace. This paper presents the preliminary findings of the intervention's impact on improving employee well-being and organizational behavior, as an indicator of potential business success. Method: Employees of a UK-based organization participated in a workplace travel behavior change intervention and used e-bikes as an active commuting mode; this was a change to their usual passive commuting behavior. The purpose of the intervention was to develop employee well-being and organizational behavior for improved business success. We explored the personal benefits and organizational co-benefits of active commuting and compared these to a travel-as-usual group of employees who did not change their behavior and continued taking non-active commutes. Results: Employees who changed their behavior to active commuting reported more positive affect, better physical health and more productive organizational behavior outcomes compared with passive commuters. In addition, there was an interactive effect of commuting mode and commuting distance: a more frequent active commute was positively associated with more productive organizational behavior and stronger overall positive employee well-being whereas a longer passive commute was associated with poorer well-being, although there was no impact on organizational behavior. Conclusion: This research provides emerging evidence of the value of an innovative workplace health promotion initiative focused on active commuting in protecting and improving employee well-being and organizational behavior for stronger business performance. It considers the significant opportunities for organizations pursuing improved workforce well-being, both in terms of employee health, and for improved organizational behavior and business success.

  4. Individual public transportation accessibility is positively associated with self-reported active commuting

    Directory of Open Access Journals (Sweden)

    Sune eDjurhuus

    2014-11-01

    Full Text Available Background: Active commuters have lower risk of chronic disease. Understanding which of the, to some extent, modifiable characteristics of public transportation that facilitate its use is thus important in a public health perspective. The aim of the study was to examine the association between individual public transportation accessibility and self-reported active commuting, and whether the associations varied with commute distance, age and gender. Methods: 28,928 commuters in the Capital Region of Denmark reported self-reported time spent either walking or cycling to work or study each day and the distance to work or study. Data were obtained from the Danish National Health Survey collected in February to April 2010. Individual accessibility by public transportation was calculated using a multimodal network in a GIS. Multilevel logistic regression was used to analyze the association between accessibility, expressed as access area, and being an active commuter.Results: Public transport accessibility area based on all stops within walking and cycling distance was positively associated with being an active commuter. Distance to work, age and gender modified the associations. Residing within 10 km commuting distance and in areas of high accessibility was associated with being an active commuter and meeting the recommendations of physical activity. For the respondents above 29 years, Individual public transportation accessibility was positively associated with being an active commuter. Women having high accessibility had significantly higher odds of being an active commuter compared to having a low accessibility. For men the associations were insignificant.Conclusions: This study extends the knowledge about the driving forces of using public transportation for commuting by examining the individual public transportation accessibility. Findings suggest that transportation accessibility supports active commuting and planning of improved public transit

  5. The Aharonov-Casher effect for spin-1 particles in non-commutative quantum mechanics

    CERN Document Server

    Dulat, Sayipjamal

    2008-01-01

    By using a generalized Bopp's shift formulation, instead of star product method, we investigate the Aharonov-Casher(AC) effect for a spin-1 neutral particle in non-commutative(NC) quantum mechanics. After solving the Kemmer equations both on a non-commutative space and a non-commutative phase space, we obtain the corrections to the topological phase of the AC effect for a spin-1 neutral particle both on a NC space and a NC phase space.

  6. A Novel Hybrid Solution for Load Commutated Inverter-Fed Induction Motor Drives

    Institute of Scientific and Technical Information of China (English)

    continued

    2004-01-01

    Load commutated inverter (LCI)based synchronous motor drives have been traditionally used in very high power applications such as pumps, compressors and fans drives. The merits oft he load commutated inverter based system are resulted from the fact that since it employs converter grade thyristors and utilizes natural commutation of the thyristors. It provides simplicity, robustness, cost effectiveness, and very low switching losses.. Moreover, be-cause it has the currentsource inverter (CSI) topology, it has inherent advantages of CSI:

  7. Commutability evaluation of reference materials of composition and properties of substances and materials

    Directory of Open Access Journals (Sweden)

    E. V. Osintseva

    2016-01-01

    Full Text Available The International Organization for Standardization laid down modern requirements for reference material producers (ISO 17034:2016, testing and calibration laboratories (ISO 15025:2005, stipulating the evaluation of reference material commutability in the course of their development (ISO Guide 35:2006 and use (ISO Guide 33:2006. The article deals with general issues of reference material commutability evaluation, the cases when the commutability evaluation is useful and the description of the approach, which may be used in the processing measurement results when evaluating the commutability of reference materials.

  8. Common Fixed Points of Weakly Contractive and Strongly Expansive Mappings in Topological Spaces

    Directory of Open Access Journals (Sweden)

    Hussain N

    2010-01-01

    Full Text Available Using the notion of weakly -contractive mappings, we prove several new common fixed point theorems for commuting as well as noncommuting mappings on a topological space X. By analogy, we obtain a common fixed point theorem of mappings which are strongly -expansive on X.

  9. First Synoptic Maps of Photospheric Vector Magnetic Field from SOLIS/VSM: Non-Radial Magnetic Fields and Hemispheric Pattern of Helicity

    CERN Document Server

    Gosain, S; Rudenko, G V; Anfinogentov, S A

    2013-01-01

    We use daily full-disk vector magnetograms from Vector Spectromagnetograph (VSM) on Synoptic Optical Long-term Investigations of the Sun (SOLIS) system to synthesize the first Carrington maps of the photospheric vector magnetic field. We describe these maps and make a comparison of observed radial field with the radial field estimate from LOS magnetograms. Further, we employ these maps to study the hemispheric pattern of current helicity density, Hc, during the rising phase of the solar cycle 24. Longitudinal average over the 23 consecutive solar rotations shows a clear signature of the hemispheric helicity rule, i.e. Hc is predominantly negative in the North and positive in South. Although our data include the early phase of cycle 24, there appears no evidence for a possible (systematic) reversal of the hemispheric helicity rule at the beginning of cycle as predicted by some dynamo models. Further, we compute the hemispheric pattern in active region latitudes (-30 deg \\le \\theta \\le 30 deg) separately for we...

  10. Magnitude and spatial patterns of erosional exhumation in the Nevadaplano, eastern Nevada and western Utah: insights from a Paleogene paleogeologic map

    Science.gov (United States)

    Long, S. P.

    2011-12-01

    The hinterland of the Sevier orogenic belt in Nevada and westernmost Utah has been interpreted as an ancient, high-elevation orogenic plateau, or 'Nevadaplano' that extensionally collapsed during Tertiary time. The cumulative effects of this extension have obscured evidence for a relict, low-relief region. To illustrate both the pre-extensional structural geometry and structural relief, a paleogeologic (or 'subcrop') map showing the distribution of Neoproterozoic, Paleozoic, and Triassic rocks exposed beneath a regional Eocene to Oligocene unconformity has been compiled for the Nevadaplano region. The map area extends from the trace of the westernmost major Sevier thrust system in western Utah to the Roberts Mountains thrust in central Nevada. Using published thicknesses of sedimentary rocks deposited in Nevada and Utah between the Neoproterozoic and the Triassic, the paleogeologic map becomes a map of exhumation, which contours the magnitude of sedimentary rock removed prior to the Paleocene. The exhumation map highlights a ~150 km wide region of low structural relief and minimal (Bolivia. Regional domains defined on the subcrop map include: 1) Cambrian subcrop levels in the hanging wall of the DeLamar-Wah-Wah-Canyon Range (DWC) thrust system and Sevier culmination, which young westward to Mississippian and higher levels; 2) a broad region of eastern Nevada and westernmost Utah that is devoid of regional-scale, surface-breaching thrust faults, and has subcrop levels between Mississippian and Triassic, indicating relatively low structural relief; and 3) subcrop levels varying between Neoproterozoic and Permian in the Central Nevada thrust belt (CNTB), indicating significant structural relief. Isolated segments of CNTB structures can be correlated by their subcrop patterns, and can be traced southward to connect with thrust faults in southern Nevada. The exhumation map can be divided into three zones that exhibit significant across-strike magnitude changes: 1) high

  11. Fock representations of Q-deformed commutation relations

    Science.gov (United States)

    BoŻejko, Marek; Lytvynov, Eugene; Wysoczański, Janusz

    2017-07-01

    We consider Fock representations of the Q-deformed commutation relations ∂s∂t†=Q (s ,t ) ∂t†∂s+δ (s ,t ) for s ,t ∈T . Here T :=Rd (or more generally T is a locally compact Polish space), the function Q :T2→C satisfies |Q (s ,t ) |≤1 and Q (s ,t ) =Q (t ,s ) ¯ , and ∫T2h (s ) g (t ) δ (s ,t ) σ (d s ) σ (d t ) :=∫Th (t ) g (t ) σ (d t ) , σ being a fixed reference measure on T. In the case, where |Q (s ,t ) |≡1 , the Q-deformed commutation relations describe a generalized statistics studied by Liguori and Mintchev. These generalized statistics contain anyon statistics as a special case (with T =R2 and a special choice of the function Q). The related Q-deformed Fock space F (H ) over H :=L2(T →C ,σ ) is constructed. An explicit form of the orthogonal projection of H⊗n onto the n-particle space Fn(H ) is derived. A scalar product in Fn(H ) is given by an operator Pn≥0 in H⊗n which is strictly positive on Fn(H ) . We realize the smeared operators ∂t† and ∂t as creation and annihilation operators in F (H ) , respectively. Additional Q-commutation relations are obtained between the creation operators and between the annihilation operators. They are of the form ∂s†∂t†=Q (t ,s ) ∂t†∂s†, ∂s∂t=Q (t ,s ) ∂t∂s, valid for those s ,t ∈T for which |Q(s, t)| = 1.

  12. BOUNDEDNESS CRITERION FOR SOME COMMUTATORS OF LINEAR OPERATORS

    Institute of Scientific and Technical Information of China (English)

    Chen Wengu; Hu Guoen

    2001-01-01

    The paper is to establish a boundedness criterion for somecommutators of linear operators when these linear operators don't satisfy the general Ap weight estimates but satisfy some radial weight estimates. CLC Number:O17 Document ID:AFoundation Item:The paper was partly supported by National Natural Science Foundation of China (No. 19901021) and Beijing Education Commission Foundation, Natural Science Foundation of Beijing (1013006). References:[1]Coifman,R. and Meyer,Y. ,Au déla Des Opérateurs Pseudo-Différentiles,Astérisque 57(1978),1-185.[2]Alvarez,J. ,Bagby,R. ,Kurtz,D. and Pérez,C. ,Weighted Estimates for Commutators of Linear Operators,Studia Math. 104 (1993),195-[2]09.[3]Hu G. and Lu S. Z. ,The Commutator of the Bochner-Riesz Operator,Tohoku Math. J. 48(1996) ,259-266.[4]Duoandikoetxea,J. ,Weighted Norm Inequalities for Homogeneous Singular Integrals,Trans.Amer,Math. Soc.[3]36(1993),869-880.[5]Stein,E. M. and Weiss,G. ,Interpolation of Operators with Change of Measures,Trans.Amer. Math. Soc. 87(1958),159-172.[6]Zaanea,A. C. ,Interpolation,North-Holland,1967.[7]Ding Y. and Lu S. Z. ,Weighted Lp-Bounedness for Higher Order Commutators of Oscillatory Singular Integrals,Tohoku Math. J. 48(1996),437-449.Manuscript Received:1999年12月22日Published:2001年9月1日

  13. A Pattern Analysis of Using Self-Organizing-Maps in a Unspoken Vowel Recognition System Based on Surface Electromyogram

    Science.gov (United States)

    Fukumoto, Hisao; Noguchi, Yusuke; Ohchi, Masashi; Furukawa, Tatsuya

    In this paper, we present some results of analysis on surface electromyogram (SEMG) using Self-Organizing -Maps (SOM) algorithm, which is one of the neural network algorithm, for unspoken vowel recognition system. Three pairs of electrodes were placed on facial muscles and SEMG signals were recorded. We have examined the classification of three pairs of the values of activity for each muscle using SOM algorithm. The SOM algorithm is also able to translate the multi-dimensional vectors of RMS values of SEMG signal into the two-dimensional map.

  14. Accelerated commutation for passive clamp isolated boost converters

    OpenAIRE

    2002-01-01

    An efficient and cost effective bidirectional DC/DC converter reduces switch voltage stress via accelerated commutation allowing use of a low-cost passive clamp circuit in boost mode. The converter includes a primary circuit, transformer and secondary circuit. The primary circuit takes the form of a “full bridge converter,” a “push-pull converter,” or an “L-type converter.”. The primary circuit may include a dissipator such as a snubber circuit or small buck converter. A secondary side of the...

  15. On the Fock representation of the q-commutation relations

    CERN Document Server

    Dykema, K J; Dykema, Ken; Nica, Alexandru

    1993-01-01

    The q-commutation relations in the title are those that have recently received much attention, and that for -1

  16. Intertwining and commutation relations for birth-death processes

    CERN Document Server

    Chafai, Djalil

    2010-01-01

    Given a birth-death process on N with semigroup P_t and a discrete gradient D depending on a positive weight u, we establish intertwining relations of the form D P_t = Q_t D, where Q_t is the Feynman-Kac semigroup with potential V_u of another birth-death process. We provide applications when V_u is positive and uniformly bounded from below, including Lipschitz contraction and Wasserstein curvature, various functional inequalities, and stochastic orderings. The proofs are remarkably simple and rely on interpolation, commutation, and convexity.

  17. Remote Sensing with Commutable Monolithic Laser and Detector

    Science.gov (United States)

    2016-01-01

    The ubiquitous trend toward miniaturized sensing systems demands novel concepts for compact and versatile spectroscopic tools. Conventional optical sensing setups include a light source, an analyte interaction region, and a separate external detector. We present a compact sensor providing room-temperature operation of monolithic surface-active lasers and detectors integrated on the same chip. The differentiation between emitter and detector is eliminated, which enables mutual commutation. Proof-of-principle gas measurements with a limit of detection below 400 ppm are demonstrated. This concept enables a crucial miniaturization of sensing devices. PMID:27785455

  18. The Commutant of Analytic Toeplitz Operators on Bergman Space

    Institute of Scientific and Technical Information of China (English)

    Yu Cheng LI

    2008-01-01

    In this paper,using the matrix skills and operator theory techniques we characterize the commutant of analytic Toeplitz operators on Bergman space.For f(z) = zng(z) (n≥1),g(z) = bo +b1zP1+b2zP2+...,bk≠0 (k = 0,1,2...),our main result is (Mf) = (Mzn)∩ (Mg) = (Mzs),where s = g.c.d.(n,p1,p2,...).In the last section,we study the relation between strongly irreducible curve and the winding number W(f,f(a) ),a ∈ D.

  19. Galois Extensions of Height-One Commuting Dynamical Systems

    CERN Document Server

    Sarkis, Ghassan

    2011-01-01

    We consider a dynamical system consisting of a pair of commuting power series, one noninvertible and another nontorsion invertible, of height one with coefficients in the $p$-adic integers. Assuming that each point of the dynamical system generates a Galois extension over the base field, we show that these extensions are in fact abelian, and, using results and considerations from the theory of the field of norms, we also show that the dynamical system must include a torsion series of maximal order. From an earlier result, this shows that the series must in fact be endomorphisms of some height-one formal group.

  20. Real algebraic geometry for matrices over commutative rings

    CERN Document Server

    Cimpric, Jaka

    2011-01-01

    We define and study preorderings and orderings on rings of the form $M_n(R)$ where $R$ is a commutative unital ring. We extend the Artin-Lang theorem and Krivine-Stengle Stellens\\"atze (both abstract and geometric) from $R$ to $M_n(R)$. While the orderings of $M_n(R)$ are in one-to-one correspondence with the orderings of $R$, this is not true for preorderings. Therefore, our theory is not Morita equivalent to the classical real algebraic geometry.