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Sample records for prehofer higher-order rewriting

  1. Higher-Order Rewriting and Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier; Rose, Kristoffer H.

    1997-01-01

    We demonstrate the usefulness of higher-order rewriting techniques for specializing programs, i.e., for partial evaluation. More precisely, we demonstrate how casting program specializers as combinatory reduction systems (CRSs) makes it possible to formalize the corresponding program...... for additional restrictions such as types that would complicate the description unnecessarily (for our purpose). In addition, partial evaluation provides a number of examples of higher-order rewriting where being higher order is a central (rather than an occasional or merely exotic) property. We illustrate...... this by demonstrating how standard but non-trivial partial-evaluation examples are handled with higher-order rewriting....

  2. Proving termination of Higher-Order Rewrite Systems

    NARCIS (Netherlands)

    Pol, J.C. van de

    1993-01-01

    This paper deals with termination proofs for Higher-Order Rewrite Systems (HRSs), introduced in [Nip9l, Nip93]. This formalism combines the computational aspects of term rewriting and simply typed lambda calculus. Our result is a proof technique for the termination of a HRS, similar to the proof tec

  3. A proof of finite family developments for higher-order rewriting using a prefix property

    NARCIS (Netherlands)

    Bruggink, H.J.S.

    2006-01-01

    A prefix property is the property that, given a reduction, the ancestor of a prefix of the target is a prefix of the source. In this paper we prove a prefix property for the class of Higher-Order Rewriting Systems with patterns (HRSs), by reducing it to a similar prefix property of a λ-calculus with

  4. Static Dependency Pair Method based on Strong Computability for Higher-Order Rewrite Systems

    CERN Document Server

    Kusakari, Keiichirou; Sakai, Masahiko; Blanqui, Frédéric

    2011-01-01

    Higher-order rewrite systems (HRSs) and simply-typed term rewriting systems (STRSs) are computational models of functional programs. We recently proposed an extremely powerful method, the static dependency pair method, which is based on the notion of strong computability, in order to prove termination in STRSs. In this paper, we extend the method to HRSs. Since HRSs include \\lambda-abstraction but STRSs do not, we restructure the static dependency pair method to allow \\lambda-abstraction, and show that the static dependency pair method also works well on HRSs without new restrictions.

  5. Higher-order (non-)modularity

    NARCIS (Netherlands)

    Appel, Claus; Oostrom, V. van; Grue Simonsen, Jakob

    2010-01-01

    We show that, contrary to the situation in first-order term rewriting, almost none of the usual properties of rewriting are modular for higher-order rewriting, irrespective of the higher-order rewriting format. For the particular format of simply typed applicative term rewriting systems we prove tha

  6. Higher-Order (Non-)Modularity

    DEFF Research Database (Denmark)

    Appel, Claus; van Oostrom, Vincent; Simonsen, Jakob Grue

    2010-01-01

    We show that, contrary to the situation in first-order term rewriting, almost none of the usual properties of rewriting are modular for higher-order rewriting, irrespective of the higher-order rewriting format. We show that for the particular format of simply typed applicative term rewriting syst...

  7. Higher-order (non-)modularity

    DEFF Research Database (Denmark)

    Appel, Claus; van Oostrom, Vincent; Simonsen, Jakob Grue

    2010-01-01

    We show that, contrary to the situation in first-order term rewriting, almost none of the usual properties of rewriting are modular for higher-order rewriting, irrespective of the higher-order rewriting format. We show that for the particular format of simply typed applicative term rewriting syst...

  8. Higher-order rewriting and partial evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier; Rose, Kristoffer H.

    1998-01-01

    transformations as meta-reductions, i.e., reductions in the internal “substitution calculus.” For partial-evaluation problems, this means that instead of having to prove on a case-by-case basis that one's “two-level functions” operate properly, one can concisely formalize them as a combinatory reduction system...... and obtain as a corollary that static reduction does not go wrong and yields a well-formed residual program. We have found that the CRS substitution calculus provides an adequate expressive power to formalize partial evaluation: it provides sufficient termination strength while avoiding the need...

  9. Higher Order Spreading Models

    CERN Document Server

    Argyros, S A; Tyros, K

    2012-01-01

    We introduce the higher order spreading models associated to a Banach space $X$. Their definition is based on $\\ff$-sequences $(x_s)_{s\\in\\ff}$ with $\\ff$ a regular thin family and the plegma families. We show that the higher order spreading models of a Banach space $X$ form an increasing transfinite hierarchy $(\\mathcal{SM}_\\xi(X))_{\\xi<\\omega_1}$. Each $\\mathcal{SM}_\\xi (X)$ contains all spreading models generated by $\\ff$-sequences $(x_s)_{s\\in\\ff}$ with order of $\\ff$ equal to $\\xi$. We also provide a study of the fundamental properties of the hierarchy.

  10. Higher-Order Hierarchies

    DEFF Research Database (Denmark)

    Ernst, Erik

    2003-01-01

    . Finally, it must be possible to write generic code that works on every hierarchy derived from the hierarchy for which it was written. This paper presents a language design that supports such a notion of higher-order hierarchies. It has been implemented in context of a full-fledged, statically typed...... be possible to create hierarchies incrementally based on existing hierarchies, such that commonalities are expressed via reuse, not duplication. Second, the hierarchies must themselves be organized into hierarchies, such that their relationships are made explicit and can be exploited in a type safe manner...... language....

  11. Higher-order risk vulnerability

    OpenAIRE

    Huang,Xiaoping; Stapleton, Richard Christopher

    2017-01-01

    We add an independent unfair background risk to higher-order risk-taking models in the current literature and examine its interaction with the main risk under consideration. Parallel to the well-known concept of risk vulnerability, which is defined by Gollier and Pratt (Econometrica 64:1109–1123, 1996), an agent is said to have a type of higher-order risk vulnerability if adding an independent unfair background risk to wealth raises his level of this type of higher-order risk aversion. We der...

  12. Nonlocal higher order evolution equations

    KAUST Repository

    Rossi, Julio D.

    2010-06-01

    In this article, we study the asymptotic behaviour of solutions to the nonlocal operator ut(x, t)1/4(-1)n-1 (J*Id -1)n (u(x, t)), x ∈ ℝN, which is the nonlocal analogous to the higher order local evolution equation vt(-1)n-1(Δ)nv. We prove that the solutions of the nonlocal problem converge to the solution of the higher order problem with the right-hand side given by powers of the Laplacian when the kernel J is rescaled in an appropriate way. Moreover, we prove that solutions to both equations have the same asymptotic decay rate as t goes to infinity. © 2010 Taylor & Francis.

  13. Higher-Order Program Generation

    DEFF Research Database (Denmark)

    Rhiger, Morten

    This dissertation addresses the challenges of embedding programming languages, specializing generic programs to specific parameters, and generating specialized instances of programs directly as executable code. Our main tools are higher-order programming techniques and automatic program generatio......), using type-directed partial evaluation. Through various back ends, including a run-time code generator, we generate ML code, C code, and OCaml byte code...

  14. Higher-Order Program Generation

    DEFF Research Database (Denmark)

    Rhiger, Morten

    to the disproportion between general programs that can be executed in several contexts and their specialized counterparts that can be executed efficiently. However, stand-alone partial evaluation is usually too costly when a program must be specialized at run time. We introduce a collection of byte-code combinators...... for OCaml, a dialect of ML, that provides run-time code generation for OCaml programs. We apply these byte-code combinators in semantics-directed compilation for an imperative language and in run-time specialization using type-directed partial evaluation. Finally, we present an approach to compiling goal......This dissertation addresses the challenges of embedding programming languages, specializing generic programs to specific parameters, and generating specialized instances of programs directly as executable code. Our main tools are higher-order programming techniques and automatic program generation...

  15. A rewriting point of view on strategies

    Directory of Open Access Journals (Sweden)

    Hélène Kirchner

    2013-03-01

    Full Text Available This paper is an expository contribution reporting on published work. It focusses on an approach followed in the rewriting community to formalize the concept of strategy. Based on rewriting concepts, several definitions of strategy are reviewed and connected: in order to catch the higher-order nature of strategies, a strategy is defined as a proof term expressed in the rewriting logic or in the rewriting calculus; to address in a coherent way deduction and computation, a strategy is seen as a subset of derivations; and to recover the definition of strategy in sequential path-building games or in functional programs, a strategy is considered as a partial function that associates to a reduction-in-progress, the possible next steps in the reduction sequence.

  16. Moments of rewriting

    African Journals Online (AJOL)

    Court of Law because there has emerged the professional called the lawyer who must speak .... The literary interview is a discourse that occupies the borderland .... rewriting should be understood as any changing of the pristine primal text into .... a moment of rewriting the Self But the resistance is also a moment of rewriting.

  17. Scoped Dynamic Rewrite Rules

    NARCIS (Netherlands)

    Visser, Eelco

    2002-01-01

    The applicability of term rewriting to program transformation is limited by the lack of control over rule application and by the context-free nature of rewrite rules. The first problem is addressed by languages supporting user-definable rewriting strategies. This paper addresses the second problem b

  18. Higher order mode optical fiber Raman amplifiers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Friis, Søren Michael Mørk; Usuga Castaneda, Mario A.

    2016-01-01

    We review higher order mode Raman amplifiers and discuss recent theoretical as well as experimental results including system demonstrations.......We review higher order mode Raman amplifiers and discuss recent theoretical as well as experimental results including system demonstrations....

  19. Challenges in higher order mode Raman amplifiers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Nielsen, Kristian; Friis, Søren Michael Mørk;

    2015-01-01

    A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed......A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed...

  20. Challenges in higher order mode Raman amplifiers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten; Nielsen, Kristian; Friis, Søren Michael Mørk

    2015-01-01

    A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed......A higher order Raman amplifier model that take random mode coupling into account ispresented. Mode dependent gain and signal power fluctuations at the output of the higher order modeRaman amplifier are discussed...

  1. Towards regularized higher-order computations in QFT without DREG

    CERN Document Server

    Sborlini, German F R; Hernandez-Pinto, Roger; Rodrigo, German

    2016-01-01

    In this talk, we review the basis of the loop-tree duality theorem, which allows to rewrite loop scattering amplitudes in terms of tree-level like objects. Since the loop measure is converted into a phase-space one, both virtual and real contributions are expressible using the same integration variables. A physically motivated momentum mapping allows to generate the real emission process starting from the Born kinematics and the loop momenta. The integrand-level combination leads to regular functions, which can be integrated without using dimensional regularization (DREG) and correctly reproduce the finite higher-order corrections to physical observables. We explain the implementation of this novel approach to compute some benchmark physical processes, and we show how to deal with both infrared and ultraviolet divergences in four space-time dimensions.

  2. Higher order resonances in dynamical systems

    CERN Document Server

    Contopoulos, George

    1978-01-01

    It is shown that the appearance of higher order resonances (that produce higher order islands on a surface of section), is not an indication of non-integrability. Examples are given and a method is described for constructing integrable Hamiltonians with higher order resonances. (11 refs).

  3. A New Look at Generalized Rewriting in Type Theory

    Directory of Open Access Journals (Sweden)

    Matthieu Sozeau

    2009-01-01

    Full Text Available Rewriting is an essential tool for computer-based reasoning, both automated and assisted. This is because rewriting is a general notion that permits modeling a wide range of problems and provides a means to effectively solve them. In a proof assistant, rewriting can be used to replace terms in arbitrary contexts, generalizing the usual equational reasoning to reasoning modulo arbitrary relations. This can be done provided the necessary proofs that functions appearing in goals are congruent with respect to specific relations. We present a new implementation of generalized rewriting in the Coq proof assistant, making essential use of the expressive power of dependent types and the recently implemented type class mechanism. The new rewrite tactic improves on and generalizes previous versions by natively supporting higher-order functions, polymorphism and subrelations. The type class system inspired by Haskell provides a perfect interface between the user and the tactic, making it easily extensible.

  4. Meaningless terms in rewriting

    NARCIS (Netherlands)

    Kennaway, R.; Oostrom, V. van; Vries, F.-J. de

    2008-01-01

    We present an axiomatic approach to the concept of meaninglessness in finite and transfinite term rewriting and lambda calculus. We justify our axioms in several ways. They can be intuitively justified from the viewpoint of rewriting as computation. They are shown to imply important properties of me

  5. ARM : abstract rewriting machine

    NARCIS (Netherlands)

    J.F.T. Kamperman; H.R. Walters (Pum)

    1993-01-01

    textabstractTerm rewriting is frequently used as implementation technique for algebraic specifications. In this paper we present the abstract term rewriting machine (ARM), which has an extremely compact instruction set and imposes no restrictions on the implemented TRSs. Apart from standard

  6. Invention, Rewriting, Usurpation

    DEFF Research Database (Denmark)

    2011-01-01

    Conference volume from the conference Invention, Rewriting, Usurpation. Discursive Fights over Religious Traditions in Antiquity, Aarhus / Ebeltoft May 30 - June 4, 2010.......Conference volume from the conference Invention, Rewriting, Usurpation. Discursive Fights over Religious Traditions in Antiquity, Aarhus / Ebeltoft May 30 - June 4, 2010....

  7. Invention, Rewriting, Usurpation

    DEFF Research Database (Denmark)

    2011-01-01

    Conference volume from the conference Invention, Rewriting, Usurpation. Discursive Fights over Religious Traditions in Antiquity, Aarhus / Ebeltoft May 30 - June 4, 2010.......Conference volume from the conference Invention, Rewriting, Usurpation. Discursive Fights over Religious Traditions in Antiquity, Aarhus / Ebeltoft May 30 - June 4, 2010....

  8. Higher order mechanics on graded bundles

    Science.gov (United States)

    Bruce, Andrew James; Grabowska, Katarzyna; Grabowski, Janusz

    2015-05-01

    In this paper we develop a geometric approach to higher order mechanics on graded bundles in both, the Lagrangian and Hamiltonian formalism, via the recently discovered weighted algebroids. We present the corresponding Tulczyjew triple for this higher order situation and derive in this framework the phase equations from an arbitrary (also singular) Lagrangian or Hamiltonian, as well as the Euler-Lagrange equations. As important examples, we geometrically derive the classical higher order Euler-Lagrange equations and analogous reduced equations for invariant higher order Lagrangians on Lie groupoids.

  9. Static Complexity Analysis of Higher Order Programs

    DEFF Research Database (Denmark)

    Avery, James Emil; Kristiansen, Lars; Moyen, Jean-Yves

    2009-01-01

    The overall goal of the research presented in this paper is to find^M automatic methods for static complexity analysis of higher order^M programs.......The overall goal of the research presented in this paper is to find^M automatic methods for static complexity analysis of higher order^M programs....

  10. Linear-algebraic Lambda-calculus: higher-order, encodings and confluence

    CERN Document Server

    Arrighi, P; Arrighi, Pablo; Dowek, Gilles

    2006-01-01

    We introduce a minimal language combining both higher-order computation and linear algebra. Roughly, this is nothing else than the Lambda-calculus together with the possibility to make linear combinations of terms a.t+b.u. We describe how to "execute" this language in terms of a few rewrite rules, and justify them through the two fundamental requirements that the language be a language of linear operators, and that it be higher-order. We mention the perspectives of this work in field of quantum computation, which we show can be easily encoded in the calculus, as well as in other domains such as the interpretation of linear logic. Finally we prove the confluence of the calculus, this is our main result. Keywords: quantum programming language, quantum control, quantum logic, probabilistic and quantitative analysis, rewriting techniques.

  11. Higher-order organization of complex networks.

    Science.gov (United States)

    Benson, Austin R; Gleich, David F; Leskovec, Jure

    2016-07-08

    Networks are a fundamental tool for understanding and modeling complex systems in physics, biology, neuroscience, engineering, and social science. Many networks are known to exhibit rich, lower-order connectivity patterns that can be captured at the level of individual nodes and edges. However, higher-order organization of complex networks--at the level of small network subgraphs--remains largely unknown. Here, we develop a generalized framework for clustering networks on the basis of higher-order connectivity patterns. This framework provides mathematical guarantees on the optimality of obtained clusters and scales to networks with billions of edges. The framework reveals higher-order organization in a number of networks, including information propagation units in neuronal networks and hub structure in transportation networks. Results show that networks exhibit rich higher-order organizational structures that are exposed by clustering based on higher-order connectivity patterns.

  12. Synchrotron radiation of higher order soliton

    CERN Document Server

    Driben, Rodislav; Efimov, Anatoly

    2015-01-01

    We demonstrate radiation mechanism exhibited by higher order soliton. In a course of its evolution higher order soliton emits polychromatic radiation resulting in appearance of multipeak frequency comb like spectral band. The shape and spectral position of this band can be effectively controlled by the relative strength of the third order dispersion. An analytical description is completely corroborated by numerical simulations. An analogy between this radiation and the radiation of moving charges is presented. For longer pulses the described effect persists also under the action of higher order perturbations such as Raman and self-steepening.

  13. Symbolic rewriting techniques

    CERN Document Server

    Weispfenning, Volker; Grabmeier, Johannes

    1998-01-01

    Symbolic rewriting techniques are methods for deriving consequences from systems of equations, and are of great use when investigating the structure of the solutions. Such techniques appear in many important areas of research within computer algebra: • the Knuth-Bendix completion for groups, monoids and general term-rewriting systems, • the Buchberger algorithm for Gröbner bases, • the Ritt-Wu characteristic set method for ordinary differential equations, and • the Riquier-Janet method for partial differential equations. This volume contains invited and contributed papers to the Symbolic Rewriting Techniques workshop, which was held at the Centro Stefano Franscini in Ascona, Switzerland, from April 30 to May 4, 1995. That workshop brought together 40 researchers from various areas of rewriting techniques, the main goal being the investigation of common threads and methods. Following the workshops, each contribution was formally refereed and 14 papers were selected for publication.

  14. Higher-order techniques in computational electromagnetics

    CERN Document Server

    Graglia, Roberto D

    2016-01-01

    Higher-Order Techniques in Computational Electromagnetics explains 'high-order' techniques that can significantly improve the accuracy, computational cost, and reliability of computational techniques for high-frequency electromagnetics, such as antennas, microwave devices and radar scattering applications.

  15. On higher order relations in Fedosov supermanifolds

    Energy Technology Data Exchange (ETDEWEB)

    Lavrov, P M; Radchenko, O V [Tomsk State Pedagogical University, 634041 Tomsk (Russian Federation)

    2006-05-26

    Higher order relations existing in normal coordinates between affine extensions of the symplectic curvature tensor and basic objects for any Fedosov supermanifolds are derived. Representation of these relations in general coordinates is discussed.

  16. Higher order relations in Fedosov supermanifolds

    CERN Document Server

    Lavrov, P M

    2005-01-01

    Higher order relations existing in normal coordinates between affine extensions of the curvature tensor and basic objects for any Fedosov supermanifolds are derived. Representation of these relations in general coordinates is discussed.

  17. Term Graph Rewriting and Parallel Term Rewriting

    CERN Document Server

    Corradini, Andrea; 10.4204/EPTCS.48.3

    2011-01-01

    The relationship between Term Graph Rewriting and Term Rewriting is well understood: a single term graph reduction may correspond to several term reductions, due to sharing. It is also known that if term graphs are allowed to contain cycles, then one term graph reduction may correspond to infinitely many term reductions. We stress that this fact can be interpreted in two ways. According to the "sequential interpretation", a term graph reduction corresponds to an infinite sequence of term reductions, as formalized by Kennaway et.al. using strongly converging derivations over the complete metric space of infinite terms. Instead according to the "parallel interpretation" a term graph reduction corresponds to the parallel reduction of an infinite set of redexes in a rational term. We formalize the latter notion by exploiting the complete partial order of infinite and possibly partial terms, and we stress that this interpretation allows to explain the result of reducing circular redexes in several approaches to te...

  18. Term Graph Rewriting and Parallel Term Rewriting

    Directory of Open Access Journals (Sweden)

    Andrea Corradini

    2011-02-01

    Full Text Available The relationship between Term Graph Rewriting and Term Rewriting is well understood: a single term graph reduction may correspond to several term reductions, due to sharing. It is also known that if term graphs are allowed to contain cycles, then one term graph reduction may correspond to infinitely many term reductions. We stress that this fact can be interpreted in two ways. According to the "sequential interpretation", a term graph reduction corresponds to an infinite sequence of term reductions, as formalized by Kennaway et.al. using strongly converging derivations over the complete metric space of infinite terms. Instead according to the "parallel interpretation" a term graph reduction corresponds to the parallel reduction of an infinite set of redexes in a rational term. We formalize the latter notion by exploiting the complete partial order of infinite and possibly partial terms, and we stress that this interpretation allows to explain the result of reducing circular redexes in several approaches to term graph rewriting.

  19. Higher-order awareness, misrepresentation and function.

    Science.gov (United States)

    Rosenthal, David

    2012-05-19

    Conscious mental states are states we are in some way aware of. I compare higher-order theories of consciousness, which explain consciousness by appeal to such higher-order awareness (HOA), and first-order theories, which do not, and I argue that higher-order theories have substantial explanatory advantages. The higher-order nature of our awareness of our conscious states suggests an analogy with the metacognition that figures in the regulation of psychological processes and behaviour. I argue that, although both consciousness and metacognition involve higher-order psychological states, they have little more in common. One thing they do share is the possibility of misrepresentation; just as metacognitive processing can misrepresent one's cognitive states and abilities, so the HOA in virtue of which one's mental states are conscious can, and sometimes does, misdescribe those states. A striking difference between the two, however, has to do with utility for psychological processing. Metacognition has considerable benefit for psychological processing; in contrast, it is unlikely that there is much, if any, utility to mental states' being conscious over and above the utility those states have when they are not conscious.

  20. A Note On Higher Order Grammar

    CERN Document Server

    Gluzberg, Victor

    2009-01-01

    Both syntax-phonology and syntax-semantics interfaces in Higher Order Grammar (HOG) are expressed as axiomatic theories in higher-order logic (HOL), i.e. a language is defined entirely in terms of provability in the single logical system. An important implication of this elegant architecture is that the meaning of a valid expression turns out to be represented not by a single, nor even by a few "discrete" terms (in case of ambiguity), but by a "continuous" set of logically equivalent terms. The note is devoted to precise formulation and proof of this observation.

  1. Rewriting Modulo SMT

    Science.gov (United States)

    Rocha, Camilo; Meseguer, Jose; Munoz, Cesar A.

    2013-01-01

    Combining symbolic techniques such as: (i) SMT solving, (ii) rewriting modulo theories, and (iii) model checking can enable the analysis of infinite-state systems outside the scope of each such technique. This paper proposes rewriting modulo SMT as a new technique combining the powers of (i)-(iii) and ideally suited to model and analyze infinite-state open systems; that is, systems that interact with a non-deterministic environment. Such systems exhibit both internal non-determinism due to the system, and external non-determinism due to the environment. They are not amenable to finite-state model checking analysis because they typically are infinite-state. By being reducible to standard rewriting using reflective techniques, rewriting modulo SMT can both naturally model and analyze open systems without requiring any changes to rewriting-based reachability analysis techniques for closed systems. This is illustrated by the analysis of a real-time system beyond the scope of timed automata methods.

  2. Human motion perception: Higher-order organization

    Science.gov (United States)

    Kaiser, Mary K.; Proffitt, Dennis R.

    1990-01-01

    An overview is given of higher-order motion perception and organization. It is argued that motion is sufficient to fully specify a number of environmental properties, including: depth order, three-dimensional form, object displacement, and dynamics. A grammar of motion perception is proposed; applications of this work for display design are discussed.

  3. Dynamical symmetry and higher-order interactions

    Energy Technology Data Exchange (ETDEWEB)

    Van Isacker, P. [Grand Accelerateur National d' Ions Lourds (GANIL), 14 - Caen (France)

    1999-07-01

    It is shown that the concept of dynamical symmetry is enriched by increasing the order the interactions between the constituent particles of a given many-body-system. The idea is illustrated with an analysis of higher-order interactions in the interacting boson model. (author)

  4. Higher-Order Minimal Functional Graphs

    DEFF Research Database (Denmark)

    Jones, Neil D; Rosendahl, Mads

    1994-01-01

    We present a minimal function graph semantics for a higher-order functional language with applicative evaluation order. The semantics captures the intermediate calls performed during the evaluation of a program. This information may be used in abstract interpretation as a basis for proving...

  5. Frontiers of higher order fuzzy sets

    CERN Document Server

    Tahayori, Hooman

    2015-01-01

    Frontiers of Higher Order Fuzzy Sets, strives to improve the theoretical aspects of general and Interval Type-2 fuzzy sets and provides a unified representation theorem for higher order fuzzy sets. Moreover, the book elaborates on the concept of gradual elements and their integration with the higher order fuzzy sets. This book also introduces new frameworks for information granulation based on general T2FSs, IT2FSs, Gradual elements, Shadowed sets and rough sets. In particular, the properties and characteristics of the new proposed frameworks are studied. Such new frameworks are shown to be more capable to be exploited in real applications. Higher order fuzzy sets that are the result of the integration of general T2FSs, IT2FSs, gradual elements, shadowed sets and rough sets will be shown to be suitable to be applied in the fields of bioinformatics, business, management, ambient intelligence, medicine, cloud computing and smart grids. Presents new variations of fuzzy set frameworks and new areas of applicabili...

  6. Analogy, higher order thinking, and education.

    Science.gov (United States)

    Richland, Lindsey Engle; Simms, Nina

    2015-01-01

    Analogical reasoning, the ability to understand phenomena as systems of structured relationships that can be aligned, compared, and mapped together, plays a fundamental role in the technology rich, increasingly globalized educational climate of the 21st century. Flexible, conceptual thinking is prioritized in this view of education, and schools are emphasizing 'higher order thinking', rather than memorization of a cannon of key topics. The lack of a cognitively grounded definition for higher order thinking, however, has led to a field of research and practice with little coherence across domains or connection to the large body of cognitive science research on thinking. We review literature on analogy and disciplinary higher order thinking to propose that relational reasoning can be productively considered the cognitive underpinning of higher order thinking. We highlight the utility of this framework for developing insights into practice through a review of mathematics, science, and history educational contexts. In these disciplines, analogy is essential to developing expert-like disciplinary knowledge in which concepts are understood to be systems of relationships that can be connected and flexibly manipulated. At the same time, analogies in education require explicit support to ensure that learners notice the relevance of relational thinking, have adequate processing resources available to mentally hold and manipulate relations, and are able to recognize both the similarities and differences when drawing analogies between systems of relationships.

  7. Higher Order Thinking in the Dance Studio

    Science.gov (United States)

    Moffett, Ann-Thomas

    2012-01-01

    The author identifies higher order thinking as an essential component of dance training for students of all ages and abilities. Weaving together insights from interviews with experts in the field of dance education with practical pedagogical applications within an Improvisation and Composition class for talented and gifted youth, this article…

  8. Higher-Order Components for Grid Programming

    CERN Document Server

    Dünnweber, Jan

    2009-01-01

    Higher-Order Components were developed within the CoreGRID European Network of Excellence and have become an optional extension of the popular Globus middleware. This book provides the reader with hands-on experience, describing a collection of example applications from various fields of science and engineering, including biology and physics.

  9. Infinitary Rewriting - Theory and Applications

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2009-01-01

    significant problem that arises in infinitary rewriting is the inherent difficulty to finitely represent and, hence, to implement it. To this end, we consider term graph rewriting, which is able to finitely represent restricted forms of infinitary term rewriting. Moreover, we study different models...

  10. A Higher-Order Colon Translation

    DEFF Research Database (Denmark)

    Danvy, Olivier; Nielsen, Lasse R.

    2000-01-01

    A lambda-encoding such as the CPS transformation gives rise to administrative redexes. In his seminal article ``Call-by-name, call-by-value and the lambda-calculus'', 25 years ago, Plotkin tackled administrative reductions using a so-called ``colon translation.'' 10 years ago, Danvy and Filinski...... integrated administrative reductions in the CPS transformation, making it operate in one pass. The technique applies to other lambda-encodings (e.g., variants of CPS), but we do not see it used in practice--instead, Plotkin's colon translation appears to be favored. Therefore, in an attempt to link both...... techniques, we recast Plotkin's proof of Indifference and Simulation to the higher-order specification of the one-pass CPS transformation. To this end, we extend his colon translation from first order to higher order...

  11. A Higher-Order Colon Translation

    DEFF Research Database (Denmark)

    Danvy, Olivier; Nielsen, Lasse Reichstein

    2001-01-01

    A lambda-encoding such as the CPS transformation gives rise to administrative redexes. In his seminal article ``Call-by-name, call-by-value and the lambda-calculus'', 25 years ago, Plotkin tackled administrative reductions using a so-called ``colon translation.'' 10 years ago, Danvy and Filinski...... integrated administrative reductions in the CPS transformation, making it operate in one pass. The technique applies to other lambda-encodings (e.g., variants of CPS), but we do not see it used in practice--instead, Plotkin's colon translation appears to be favored. Therefore, in an attempt to link both...... techniques, we recast Plotkin's proof of Indifference and Simulation to the higher-order specification of the one-pass CPS transformation. To this end, we extend his colon translation from first order to higher order...

  12. Higher order structure in ribosomal RNA.

    Science.gov (United States)

    Gutell, R R; Noller, H F; Woese, C R

    1986-05-01

    The only reliable general method currently available for determining precise higher order structure in the large ribosomal RNAs is comparative sequence analysis. The method is here applied to reveal 'tertiary' structure in the 16S-like rRNAs, i.e. structure more complex than simple double-helical, secondary structure. From a list of computer-generated potential higher order interactions within 16S rRNA one such interaction considered likely was selected for experimental test. The putative interaction involves a Watson-Crick one to one correspondence between positions 570 and 866 in the molecule (E. coli numbering). Using existing oligonucleotide catalog information several organisms were selected whose 16S rRNA sequences might test the proposed co-variation. In all of the (phylogenetically independent) cases selected, full sequence evidence confirms the predicted one to one (Watson-Crick) correspondence. An interaction between positions 570 and 866 is, therefore, considered proven phylogenetically.

  13. Higher-Order Mentalising and Executive Functioning.

    Science.gov (United States)

    2015-11-01

    Higher-order mentalising is the ability to represent the beliefs and desires of other people at multiple, iterated levels - a capacity that sets humans apart from other species. However, there has not yet been a systematic attempt to determine what cognitive processes underlie this ability. Here we present three correlational studies assessing the extent to which performance on higher-order mentalising tasks relates to emotion recognition, self-reported empathy and self-inhibition. In Study 1a and 1b, examining emotion recognition and empathy, a relationship was identified between individual differences in the ability to mentalise and an emotion recognition task (the Reading the Mind in the Eyes task), but no correlation was found with the Empathy Quotient, a self-report scale of empathy. Study 2 investigated whether a relationship exists between individual mentalising abilities and four different forms of self-inhibition: motor inhibition, executive inhibition, automatic imitation and temporal discounting. Results demonstrate that only temporal discounting performance relates to mentalising ability; suggesting that cognitive skills relevant to representation of the minds of others' are not influenced by the ability to perform more basic inhibition. Higher-order mentalising appears to rely on the cognitive architecture that serves both low-level social cognition (emotion recognition), and complex forms of inhibition.

  14. Triangulation in rewriting

    NARCIS (Netherlands)

    Oostrom, V. van; Zantema, Hans

    2012-01-01

    We introduce a process, dubbed triangulation, turning any rewrite relation into a confluent one. It is more direct than usual completion, in the sense that objects connected by a peak are directly oriented rather than their normal forms. We investigate conditions under which this process preserves d

  15. Triangulation in rewriting

    NARCIS (Netherlands)

    Oostrom, V. van; Zantema, Hans

    2012-01-01

    We introduce a process, dubbed triangulation, turning any rewrite relation into a confluent one. It is more direct than usual completion, in the sense that objects connected by a peak are directly oriented rather than their normal forms. We investigate conditions under which this process preserves d

  16. Higher-Order Aberrations in Myopic Eyes

    Directory of Open Access Journals (Sweden)

    Farid Karimian

    2010-01-01

    Full Text Available Purpose: To evaluate the correlation between refractive error and higher-order aberrations (HOAs in patients with myopic astigmatism. Methods: HOAs were measured using the Zywave II aberrometer over a 6 mm pupil. Correlations between HOAs and myopia, astigmatism, and age were analyzed. Results: One hundred and twenty-six eyes of 63 subjects with mean age of 26.4±5.9 years were studied. Mean spherical equivalent refractive error and refractive astigmatism were -4.94±1.63 D and 0.96±1.06 D, respectively. The most common higher-order aberration was primary horizontal trefoil with mean value of 0.069±0.152 μm followed by spherical aberration (-0.064±0.130 μm and primary vertical coma (-0.038±0.148 μm. As the order of aberration increased from third to fifth, its contribution to total HOA decreased: 53.9% for third order, 31.9% for fourth order, and 14.2% for fifth order aberrations. Significant correlations were observed between spherical equivalent refractive error and primary horizontal coma (R=0.231, P=0.022, and root mean square (RMS of spherical aberration (R=0.213, P=0.031; between astigmatism and RMS of total HOA (R=0.251, P=0.032, RMS of fourth order aberration (R=0.35, P<0.001, and primary horizontal coma (R=0.314, P=0.004. Spherical aberration (R=0.214, P=0.034 and secondary vertical coma (R=0.203, P=0.031 significantly increased with age. Conclusion: Primary horizontal trefoil, spherical aberration and primary vertical coma are the predominant higher-order aberrations in eyes with myopic astigmatism.

  17. Extending CASL with Higher-order Functions

    DEFF Research Database (Denmark)

    Haxthausen, Anne; Krieg-Brückner, Bernd; Mossakowski, Till

    1998-01-01

    We present a proposal for the design of the higher-order extension of CASL. For each design step, we have tried to find the best of several possible alternatives, give a motivation for the preferred alternative and argue why the other alternatives are not taken. This note discusses function spaces......, product types, partial functions, predicates, subsorting, signature morphisms and \\-abstraction. A forthcoming note will be devoted to polymorphism, type constructors and dependent types. A companion note, replacing L-2, will explain the formal details of the proposal made in this note....

  18. The regular state in higher order gravity

    Science.gov (United States)

    Cotsakis, Spiros; Kadry, Seifedine; Trachilis, Dimitrios

    2016-08-01

    We consider the higher-order gravity theory derived from the quadratic Lagrangian R + 𝜖R2 in vacuum as a first-order (ADM-type) system with constraints, and build time developments of solutions of an initial value formulation of the theory. We show that all such solutions, if analytic, contain the right number of free functions to qualify as general solutions of the theory. We further show that any regular analytic solution which satisfies the constraints and the evolution equations can be given in the form of an asymptotic formal power series expansion.

  19. Higher-Order Gauss-Bonnet Cosmology

    CERN Document Server

    Capozziello, Salvatore; Makarenko, Andrey N

    2014-01-01

    We study cosmological models derived from higher-order Gauss-Bonnet gravity $F(R,G)$ by using the Lagrange multiplier approach without assuming the presence of additional fields with the exception of standard perfect fluid matter. The presence of Lagrange multipliers reduces the number of allowed solutions. We need to introduce compatibility conditions of the FRW equations, which impose strict restrictions on the metric or require the introduction of additional exotic matter. Several classes of $F(R,G)$ models are generated and discussed.

  20. Higher Order Equations and Constituent Fields

    Science.gov (United States)

    Barci, D. G.; Bollini, C. G.; Oxman, L. E.; Rocca, M.

    We consider a simple wave equation of fourth degree in the D'Alembertian operator. It contains the main ingredients of a general Lorentz-invariant higher order equation, namely, a normal bradyonic sector, a tachyonic state and a pair of complex conjugate modes. The propagators are respectively the Feynman causal function and three Wheeler-Green functions (half-advanced and half-retarded). The latter are Lorentz-invariant and consistent with the elimination of tachyons and complex modes from free asymptotic states. We also verify the absence of absorptive parts from convolutions involving Wheeler propagators.

  1. Adaptive filtering using Higher Order Statistics (HOS

    Directory of Open Access Journals (Sweden)

    Abdelghani Manseur

    2012-03-01

    Full Text Available The performed job, in this study, consists in studying adaptive filters and higher order statistics (HOS to ameliorate their performances, by extension of linear case to non linear filters via Volterra series. This study is, principally, axed on: „ Choice of the adaptation step and convergence conditions. „ Convergence rate. „ Adaptive variation of the convergence factor, according to the input signal. The obtained results, with real signals, have shown computationally efficient and numerically stable algorithms for adaptive nonlinear filtering while keeping relatively simple computational complexity.

  2. Nonconservative higher-order hydrodynamic modulation instability

    Science.gov (United States)

    Kimmoun, O.; Hsu, H. C.; Kibler, B.; Chabchoub, A.

    2017-08-01

    The modulation instability (MI) is a universal mechanism that is responsible for the disintegration of weakly nonlinear narrow-banded wave fields and the emergence of localized extreme events in dispersive media. The instability dynamics is naturally triggered, when unstable energy sidebands located around the main energy peak are excited and then follow an exponential growth law. As a consequence of four wave mixing effect, these primary sidebands generate an infinite number of additional sidebands, forming a triangular sideband cascade. After saturation, it is expected that the system experiences a return to initial conditions followed by a spectral recurrence dynamics. Much complex nonlinear wave field motion is expected, when the secondary or successive sideband pair that is created is also located in the finite instability gain range around the main carrier frequency peak. This latter process is referred to as higher-order MI. We report a numerical and experimental study that confirms observation of higher-order MI dynamics in water waves. Furthermore, we show that the presence of weak dissipation may counterintuitively enhance wave focusing in the second recurrent cycle of wave amplification. The interdisciplinary weakly nonlinear approach in addressing the evolution of unstable nonlinear waves dynamics may find significant resonance in other nonlinear dispersive media in physics, such as optics, solids, superfluids, and plasma.

  3. Higher order assortativity in complex networks

    CERN Document Server

    Arcagni, Alberto; Stefani, Silvana; Torriero, Anna

    2016-01-01

    Assortativity was first introduced by Newman and has been extensively studied and applied to many real world networked systems since then. Assortativity is a graph metrics and describes the tendency of high degree nodes to be directly connected to high degree nodes and low degree nodes to low degree nodes. It can be interpreted as a first order measure of the connection between nodes, i.e. the first autocorrelation of the degree-degree vector. Even though assortativity has been used so extensively, to the author's knowledge, no attempt has been made to extend it theoretically. This is the scope of our paper. We will introduce higher order assortativity by extending the Newman index based on a suitable choice of the matrix driving the connections. Higher order assortativity will be defined for paths, shortest paths, random walks of a given time length, connecting any couple of nodes. The Newman assortativity is achieved for each of these measures when the matrix is the adjacency matrix, or, in other words, the...

  4. Enhanced higher order parametric x radiation production

    Science.gov (United States)

    Dinova, Kay L.

    1992-12-01

    This thesis examines parametric x-radiation (PXR) which is the Bragg scattering of the virtual photons associated with the Coulomb field of relativistic charged particle from the atomic planes of a crystal. Higher order parametric x-radiation from the (002) planes of a thick mosaic graphite crystal have been observed. The raw PXR data was collected using a SiLi detector and a Pulse Height Analyzer (PHA) software program. The data was corrected for various effects including attenuation, detector drift, and efficiency. The absolute number of photons per electron was obtained by using the fluorescent x-ray yield from a tin foil backing on the graphite crystal to determine the LINAC current. The number of photons per electron observed greatly exceeds the expected values. Comparison of the ratio of intensity of a given order to the first order I(n)/I(I) to the theoretical ratio shows that the ratios increase with order. Not only is the absolute intensity greater than expected, but the higher orders (compared to the first order) are larger than expected. Lastly, the intensity for various crystal angle orientations and a fixed detector angle was measured.

  5. Conformal higher-order viscoelastic fluid mechanics

    CERN Document Server

    Fukuma, Masafumi

    2012-01-01

    We present a generally covariant formulation of conformal higher-order viscoelastic fluid mechanics with strain allowed to take arbitrarily large values. We give a general prescription to determine the dynamics of a relativistic viscoelastic fluid in a way consistent with the hypothesis of local thermodynamic equilibrium and the second law of thermodynamics. We then elaborately study the transient time scales at which the strain almost relaxes and becomes proportional to the gradients of velocity. We particularly show that a conformal second-order fluid with all possible parameters in the constitutive equations can be obtained without breaking the hypothesis of local thermodynamic equilibrium, if the conformal fluid is defined as the long time limit of a conformal second-order viscoelastic system. We also discuss how local thermodynamic equilibrium could be understood in the context of the fluid/gravity correspondence.

  6. Conformal higher-order viscoelastic fluid mechanics

    Science.gov (United States)

    Fukuma, Masafumi; Sakatani, Yuho

    2012-06-01

    We present a generally covariant formulation of conformal higher-order viscoelastic fluid mechanics with strain allowed to take arbitrarily large values. We give a general prescription to determine the dynamics of a relativistic viscoelastic fluid in a way consistent with the hypothesis of local thermodynamic equilibrium and the second law of thermodynamics. We then elaborately study the transient time scales at which the strain almost relaxes and becomes proportional to the gradients of velocity. We particularly show that a conformal second-order fluid with all possible parameters in the constitutive equations can be obtained without breaking the hypothesis of local thermodynamic equilibrium, if the conformal fluid is defined as the long time limit of a conformal second-order viscoelastic system. We also discuss how local thermodynamic equilibrium could be understood in the context of the fluid/gravity correspondence.

  7. Focus and Higher-Order Unification

    CERN Document Server

    Gardent, C; Gardent, Claire; Kohlhase, Michael

    1996-01-01

    Pulman has shown that Higher--Order Unification (HOU) can be used to model the interpretation of focus. In this paper, we extend the unification--based approach to cases which are often seen as a test--bed for focus theory: utterances with multiple focus operators and second occurrence expressions. We then show that the resulting analysis favourably compares with two prominent theories of focus (namely, Rooth's Alternative Semantics and Krifka's Structured Meanings theory) in that it correctly generates interpretations which these alternative theories cannot yield. Finally, we discuss the formal properties of the approach and argue that even though HOU need not terminate, for the class of unification--problems dealt with in this paper, HOU avoids this shortcoming and is in fact computationally tractable.

  8. Higher order modes in photonic crystal slabs.

    Science.gov (United States)

    Gansch, Roman; Kalchmair, Stefan; Detz, Hermann; Andrews, Aaron M; Klang, Pavel; Schrenk, Werner; Strasser, Gottfried

    2011-08-15

    We present a detailed investigation of higher order modes in photonic crystal slabs. In such structures the resonances exhibit a blue-shift compared to an ideal two-dimensional photonic crystal, which depends on the order of the slab mode and the polarization. By fabricating a series of photonic crystal slab photo detecting devices, with varying ratios of slab thickness to photonic crystal lattice constant, we are able to distinguish between 0th and 1st order slab modes as well as the polarization from the shift of resonances in the photocurrent spectra. This method complements the photonic band structure mapping technique for characterization of photonic crystal slabs. © 2011 Optical Society of America

  9. Dynamic analysis of higher order biological systems.

    Science.gov (United States)

    Sato, K

    1981-01-01

    Humans and animals consist of a variety of bio-systems exhibiting various bio-phenomena over the course of time, from the past to the present and into future, up to just before their death. Each state of a bio-phenomenon at any time is related in stochastic fashion not only to its past history, but those of many other bio- and natural phenomena, enormous in number, in their internal and external environments. Most states of these bio-phenomena sway more or less around respective averages, which suggest their levels of homeostasis, essentially important for maintaining life. In the above past history of sway was hidden an essential characteristic, i.e., dynamic higher-order activity, of the bio-system, whereas the bio- and natural phenomena in the environments act to drive, i.e., stimulate, as an ensemble, the bio-system to exhibit the bio-phenomena as its responses. From this new point of view, mono- and multivariate dynamic stimulation-system (activity)-response relations in stochastic fashion can be seen as an extension leading from of one of the most fundamental static laws of excitability, that is the threshold stimulus-excitability-unit response relation in physiology. The dynamic mono- and multivariate higher-order activities, each of which consisted of some first- and second-order component activities, can be described in the frequency and time-patterns as the power spectral densities or frequency responses and (unit) impulse responses, respectively. Some of these "dynamic activities" were manifested in the brain system of humans and cats, the human "posture holding system," "the pressure regulatory system" in the human pulmonary circulation and the "glucoregulatory system" of dogs, respectively.

  10. Rewriting the Genetic Code.

    Science.gov (United States)

    Mukai, Takahito; Lajoie, Marc J; Englert, Markus; Söll, Dieter

    2017-09-08

    The genetic code-the language used by cells to translate their genomes into proteins that perform many cellular functions-is highly conserved throughout natural life. Rewriting the genetic code could lead to new biological functions such as expanding protein chemistries with noncanonical amino acids (ncAAs) and genetically isolating synthetic organisms from natural organisms and viruses. It has long been possible to transiently produce proteins bearing ncAAs, but stabilizing an expanded genetic code for sustained function in vivo requires an integrated approach: creating recoded genomes and introducing new translation machinery that function together without compromising viability or clashing with endogenous pathways. In this review, we discuss design considerations and technologies for expanding the genetic code. The knowledge obtained by rewriting the genetic code will deepen our understanding of how genomes are designed and how the canonical genetic code evolved.

  11. Higher Order Cumulants in Colorless Partonic Plasma

    CERN Document Server

    Cherif, S; Ladrem, M

    2016-01-01

    Any physical system considered to study the QCD deconfinement phase transition certainly has a finite volume, so the finite size effects are inevitably present. This renders the location of the phase transition and the determination of its order as an extremely difficult task, even in the simplest known cases. In order to identify and locate the colorless QCD deconfinement transition point in finite volume $T_{0}(V)$, a new approach based on the finite-size cumulant expansion of the order parameter and the $\\mathscr{L}_{m,n}$-Method is used.We have shown that both cumulants of higher order and their ratios, associated to the thermodynamical fluctuations of the order parameter, in QCD deconfinement phase transition behave in a particular enough way revealing pronounced oscillations in the transition region. The sign structure and the oscillatory behavior of these in the vicinity of the deconfinement phase transition point might be a sensitive probe and may allow one to elucidate their relation to the QCD phase...

  12. Aspects of general higher-order gravities

    CERN Document Server

    Bueno, Pablo; Min, Vincent S; Visser, Manus R

    2016-01-01

    We study several aspects of higher-order gravities constructed from general contractions of the Riemann tensor and the metric in arbitrary dimensions. First, we use the fast-linearization procedure presented in arXiv:1607.06463 to obtain the equations satisfied by the metric perturbation modes on a maximally symmetric background in the presence of matter and to classify $\\mathcal{L}($Riemann$)$ theories according to their spectrum. Then, we linearize all theories up to quartic order in curvature and use this result to construct quartic versions of Einsteinian cubic gravity (ECG). In addition, we show that the most general cubic gravity constructed in a dimension-independent way and which does not propagate the ghost-like spin-2 mode (but can propagate the scalar) is a linear combination of $f($Lovelock$)$ invariants, plus the ECG term, plus a New ghost-free gravity term. Next, we construct the generalized Newton potential and the Post-Newtonian parameter $\\gamma$ for general $\\mathcal{L}($Riemann$)$ gravities...

  13. A Modular Rewriting Semantics for CML

    DEFF Research Database (Denmark)

    Chalub, Fabricio; Braga, Christiano de Oliveira

    2004-01-01

    This paper presents a modular rewriting semantics (MRS) specification for Reppy's Concurrent ML (CML), based on Peter Mosses' modular structural operational semantics specification for CML. A modular rewriting semantics specification for a programming language is a rewrite theory in rewriting log...

  14. Modes of Convergence for Term Graph Rewriting

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2011-01-01

    Term graph rewriting provides a simple mechanism to finitely represent restricted forms of infinitary term rewriting. The correspondence between infinitary term rewriting and term graph rewriting has been studied to some extent. However, this endeavour is impaired by the lack of an appropriate co...

  15. A Modular Rewriting Semantics for CML

    DEFF Research Database (Denmark)

    Chalub, Fabricio; Braga, Christiano de Oliveira

    2004-01-01

    This paper presents a modular rewriting semantics (MRS) specification for Reppy's Concurrent ML (CML), based on Peter Mosses' modular structural operational semantics specification for CML. A modular rewriting semantics specification for a programming language is a rewrite theory in rewriting log...... of rewriting logic, and to verify CML programs using Maude's built-in LTL model checker. It is assumed that the reader is familiar with basic concepts of structural operational semantics and algebraic specifications....

  16. HIGHER ORDER MULTIVARIABLE NORLUND EULER-BERNOULLI POLYNOMIALS

    Institute of Scientific and Technical Information of China (English)

    刘国栋

    2002-01-01

    The definitions of higher order multivariable Norlund Euler polynomials and Norlund Bernoulli polynomials are presented and some of their important properties are expounded. Some identities involving recurrence sequences and higher order multivariable Norlund Euler-Bernoulli polynomials are established.

  17. Generalizations of Euler Numbers and Euler Numbers of Higher Order

    Institute of Scientific and Technical Information of China (English)

    LUOQiu-ming; QIFeng

    2005-01-01

    The purpose of this paper is to define the generalized Euler numbers and the generalized Euler numbers of higher order, their recursion formula and some properties were established, accordingly Euler numbers and Euler numbers of higher order were extended.

  18. Higher-orders in heavy quark processes within the LTD approach

    CERN Document Server

    Sborlini, German F R

    2016-01-01

    The computation of perturbative corrections to processes involving heavy quarks is crucial for the precision program of the LHC and future colliders. In this article, we describe a powerful approach to calculate higher-orders in QCD skipping the traditional subtraction method. Our proposal is based on the loop-tree duality (LTD) theorem, which allows to rewrite virtual contributions in terms of integrals over the real emission phase-space. Then, we proceed to combine both real and virtual contributions at the integrand level, obtaining regular expressions that can be numerically integrated in four space-time dimensions. In this way, we avoid dealing with complicated massive Feynman integrals and introducing infrared counter-terms. Some reference examples are explained, in order to exhibit the potential of our method.

  19. A Formalization of Newman's and Yokouchi's Lemmas in a Higher-Order Language

    Directory of Open Access Journals (Sweden)

    Andre Luiz Galdino

    2008-12-01

    Full Text Available This paper shows how a formalization for the theory of Abstract Reduction Systems (ARSs in which noetherianity was specified by the notion of well-foundness over binary relations is used in order to prove results such as the well-known Newman's and Yokouchi's Lemmas. The former is known as the diamond lemma and the latter states a property of commutation between ARSs. The theory ars was specified in the Prototype Verification System (PVS for which to the best of our knowledge there was no available theory for dealing with rewriting techniques in general before this development. In addition to proof techniques available in the higher-order specification language of PVS, the verification of these lemmas implies an elaborated use of natural and noetherian induction.

  20. Conceptualizing and Assessing Higher-Order Thinking in Reading

    Science.gov (United States)

    Afflerbach, Peter; Cho, Byeong-Young; Kim, Jong-Yun

    2015-01-01

    Students engage in higher-order thinking as they read complex texts and perform complex reading-related tasks. However, the most consequential assessments, high-stakes tests, are currently limited in providing information about students' higher-order thinking. In this article, we describe higher-order thinking in relation to reading. We provide a…

  1. Rewriting Modulo SMT and Open System Analysis

    Science.gov (United States)

    Rocha, Camilo; Meseguer, Jose; Munoz, Cesar

    2014-01-01

    This paper proposes rewriting modulo SMT, a new technique that combines the power of SMT solving, rewriting modulo theories, and model checking. Rewriting modulo SMT is ideally suited to model and analyze infinite-state open systems, i.e., systems that interact with a non-deterministic environment. Such systems exhibit both internal non-determinism, which is proper to the system, and external non-determinism, which is due to the environment. In a reflective formalism, such as rewriting logic, rewriting modulo SMT can be reduced to standard rewriting. Hence, rewriting modulo SMT naturally extends rewriting-based reachability analysis techniques, which are available for closed systems, to open systems. The proposed technique is illustrated with the formal analysis of: (i) a real-time system that is beyond the scope of timed-automata methods and (ii) automatic detection of reachability violations in a synchronous language developed to support autonomous spacecraft operations.

  2. Rewriting Constraint Models with Metamodels

    CERN Document Server

    Chenouard, Raphael; Soto, Ricardo

    2010-01-01

    An important challenge in constraint programming is to rewrite constraint models into executable programs calculat- ing the solutions. This phase of constraint processing may require translations between constraint programming lan- guages, transformations of constraint representations, model optimizations, and tuning of solving strategies. In this paper, we introduce a pivot metamodel describing the common fea- tures of constraint models including different kinds of con- straints, statements like conditionals and loops, and other first-class elements like object classes and predicates. This metamodel is general enough to cope with the constructions of many languages, from object-oriented modeling languages to logic languages, but it is independent from them. The rewriting operations manipulate metamodel instances apart from languages. As a consequence, the rewriting operations apply whatever languages are selected and they are able to manage model semantic information. A bridge is created between the metamode...

  3. Binary decision diagrams by shared rewriting

    NARCIS (Netherlands)

    Pol, J. van de; Zantema, H.

    2000-01-01

    BDDs provide an established technique for propositional formula manipulation. In this paper we re-develope the basic BDD theory using standard rewriting techniques. Since a BDD is a DAG instead of a tree we need a notion of shared rewriting and develope appropriate theory. A rewriting system is

  4. Skinner-Rusk unified formalism for higher-order systems

    Science.gov (United States)

    Prieto-Martínez, Pedro Daniel; Román-Roy, Narciso

    2012-07-01

    The Lagrangian-Hamiltonian unified formalism of R. Skinner and R. Rusk was originally stated for autonomous dynamical systems in classical mechanics. It has been generalized for non-autonomous first-order mechanical systems, first-order and higher-order field theories, and higher-order autonomous systems. In this work we present a generalization of this formalism for higher-order non-autonomous mechanical systems.

  5. Higher Order Diffraction Characteristics of Fiber Bragg Grating

    Directory of Open Access Journals (Sweden)

    Sunita P. Ugale

    2013-02-01

    Full Text Available The effect of grating saturation on higher order diffraction characteristic of FBG is investigated by using Coupled mode theory. Grating saturation effects were considered in the index distribution model showing the significant influence on the coupling process and hence on the reflectivity characteristics of FBG. Maximum reflectivity curves for first and higher order diffraction of FBG are plotted for different values of saturation coefficient. The effect of change in length and change in refractive index are studied. The behavior of grating for higher order of diffraction is totally different than first order of diffraction. In saturated gratings, the higher order diffraction can be utilized for multiparameter sensing

  6. Adaptive Integral Method for Higher Order Method of Moments

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Meincke, Peter

    2008-01-01

    The adaptive integral method (AIM) is combined with the higher order method of moments (MoM) to solve integral equations. The technique takes advantage of the low computational complexity and memory requirements of the AIM and the reduced number of unknowns and higher order convergence of higher...... order basis functions. The classical AIM is appropriately modified to allow larger discretization elements and, consequently, higher basis function expansion orders. Numerical examples based on the higher order hierarchical Legendre basis functions show the advantages of the proposed technique over...... the classical AIM based on low-order basis functions in terms of memory and computational time....

  7. On the fractional counterpart of the higher-order equations

    CERN Document Server

    D'Ovidio, Mirko

    2011-01-01

    In this work we study the solutions to some fractional higher-order equations. Special cases in which time-fractional derivatives take integer values are also examined and the explicit solutions are presented. Such solutions can be expressed by means of the transition laws of stable subordinators and their inverse processes. In particular we establish connections between fractional and higher-order equations.

  8. Higher Order Thinking: Definition, Meaning and Instructional Approaches.

    Science.gov (United States)

    Thomas, Ruth G., Ed.

    This publication shares current thinking, research, and practice in the area of higher order thinking skills with home economics educators, including teachers, supervisors, and teacher educators. The first three articles provide general discussions of thinking skills. They are "Introduction" (Ruth Pestle); "Can Higher Order Thinking…

  9. Numbers of Subnormal Solutions for Higher Order Periodic Differential Equations

    Institute of Scientific and Technical Information of China (English)

    Zong Xuan CHEN; Kwang Ho SHON

    2011-01-01

    In this paper,we estimate the number of subnormal solutions for higher order linear periodic differential equations,and estimate the growth of subnormal solutions and all other solutions.We also give a representation of subnormal solutions of a class of higher order linear periodic differential equations.

  10. Reinterpreting Compression in Infinitary Rewriting

    NARCIS (Netherlands)

    Ketema, J.; Tiwari, Ashish

    2012-01-01

    Departing from a computational interpretation of compression in infinitary rewriting, we view compression as a degenerate case of standardisation. The change in perspective comes about via two observations: (a) no compression property can be recovered for non-left-linear systems and (b) some standar

  11. Conservation Laws in Higher-Order Nonlinear Optical Effects

    CERN Document Server

    Kim, J; Shin, H J; Kim, Jongbae

    1999-01-01

    Conservation laws of the nonlinear Schrödinger equation are studied in the presence of higher-order nonlinear optical effects including the third-order dispersion and the self-steepening. In a context of group theory, we derive a general expression for infinitely many conserved currents and charges of the coupled higher-order nonlinear Schrödinger equation. The first few currents and charges are also presented explicitly. Due to the higher-order effects, conservation laws of the nonlinear Schrödinger equation are violated in general. The differences between the types of the conserved currents for the Hirota and the Sasa-Satsuma equations imply that the higher-order terms determine the inherent types of conserved quantities for each integrable cases of the higher-order nonlinear Schrödinger equation.

  12. Higher order factors of personality: do they exist?

    Science.gov (United States)

    Ashton, Michael C; Lee, Kibeom; Goldberg, Lewis R; de Vries, Reinout E

    2009-05-01

    Scales that measure the Big Five personality factors are often substantially intercorrelated. These correlations are sometimes interpreted as implying the existence of two higher order factors of personality. The authors show that correlations between measures of broad personality factors do not necessarily imply the existence of higher order factors and might instead be due to variables that represent same-signed blends of orthogonal factors. Therefore, the hypotheses of higher order factors and blended variables can only be tested with data on lower level personality variables that define the personality factors. The authors compared the higher order factor model and the blended variable model in three participant samples using the Big Five Aspect Scales, and found better fit for the latter model. In other analyses using the HEXACO Personality Inventory, they identified mutually uncorrelated markers of six personality factors. The authors conclude that correlations between personality factor scales can be explained without postulating any higher order dimensions of personality.

  13. Higher-order mode photonic crystal based nanofluidic sensor

    Science.gov (United States)

    Peng, Wang; Chen, Youping; Ai, Wu

    2017-01-01

    A higher-order photonic crystal (PC) based nanofluidic sensor, which worked at 532 nm, was designed and demonstrated. A systematical and detailed method for sculpturing a PC sensor for a given peak wavelength value (PWV) and specified materials was illuminated. It was the first time that the higher order mode was used to design PC based nanofluidic sensor, and the refractive index (RI) sensitivity of this sensor had been verified with FDTD simulation software from Lumerical. The enhanced electrical field of higher order mode structure was mostly confined in the channel area, where the enhance field is wholly interacting with the analytes in the channels. The comparison of RI sensitivity between fundamental mode and higher order mode shows the RI variation of higher order mode is 124.5 nm/RIU which is much larger than the fundamental mode. The proposed PC based nanofluidic structure pioneering a novel style for future optofluidic design.

  14. Higher-order harmonics of general limited diffraction Bessel beams

    Science.gov (United States)

    Ding, De-Sheng; Huang, Jin-Huang

    2016-12-01

    In this paper, we extensively study the higher-order harmonic generation of the general limited diffraction m-th-order Bessel beam. The analysis is based on successive approximations of the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation. Asymptotic expansions are presented for higher-order harmonic Bessel beams in near and far fields. The validity of asymptotic approximation is also analyzed. The higher-order harmonic of the Bessel beam with the lowest zero-order is taken as a special example. Project supported by the National Natural Science Foundation of China (Grant Nos. 11074038 and 11374051).

  15. Solution of Higher-Order ODEs Using Backward Difference Method

    Directory of Open Access Journals (Sweden)

    Mohamed Bin Suleiman

    2011-01-01

    Full Text Available The current numerical technique for solving a system of higher-order ordinary differential equations (ODEs is to reduce it to a system of first-order equations then solving it using first-order ODE methods. Here, we propose a method to solve higher-order ODEs directly. The formulae will be derived in terms of backward difference in a constant stepsize formulation. The method developed will be validated by solving some higher-order ODEs directly with constant stepsize. To simplify the evaluations of the integration coefficients, we find the relationship between various orders. The result presented confirmed our hypothesis.

  16. Demand-Driven Higher-Order Fixpoint Iteration

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    Our aim is to show that techniques from higher-order strictness analysis may be used as a general algorithmic principle in a functional programming language. Certain problems may be expressed as the search for the least solution that satisfy certain given properties. This is often done using some...... kind of fixpoint iteration. We will present a fixpoint operation that can be used for second-order functions and extend this to higher-order functions. The technique is based on using partial function graphs to represent higher-order objects. The main problem in finding fixpoints for higher......-order functions is to establish a notion of {\\em neededness} so as to restrict the iteration to those parts of the function that may influence the result. This is here done through a uniform extension of the domain of values with need information. The result is an iteration strategy which will terminate if base...

  17. Unambiguous formalism for higher order Lagrangian field theories

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Cedric M; De Leon, Manuel; De Diego, David MartIn [Instituto de Ciencias Matematicas, CSIC-UAM-UC3M-UCM, Serrano 123, 28006 Madrid (Spain); Vankerschaver, Joris [Control and Dynamical Systems, California Institute of Technology, CA (United States)], E-mail: cedricmc@imaff.cfmac.csic.es, E-mail: mdeleon@imaff.cfmac.csic.es, E-mail: d.martin@imaff.cfmac.csic.es, E-mail: jv@caltech.edu

    2009-11-27

    The aim of this paper is to propose an unambiguous intrinsic formalism for higher order field theories which avoids the arbitrariness in the generalization of the conventional description of field theories, and implies the existence of different Cartan forms and Legendre transformations. We propose a differential-geometric setting for the dynamics of a higher order field theory, based on the Skinner and Rusk formalism for mechanics. This approach incorporates aspects of both the Lagrangian and the Hamiltonian description, since the field equations are formulated using the Lagrangian on a higher order jet bundle and the canonical multisymplectic form on its affine dual. As both of these objects are uniquely defined, the Skinner-Rusk approach has the advantage that it does not suffer from the arbitrariness in conventional descriptions. The result is that we obtain a unique and global intrinsic version of the Euler-Lagrange equations for higher order field theories. Several examples illustrate our construction.

  18. Development of a core confidence-higher order construct.

    Science.gov (United States)

    Stajkovic, Alexander D

    2006-11-01

    The author develops core confidence as a higher order construct and suggests that a core confidence-higher order construct--not addressed by extant work motivation theories--is helpful in better understanding employee motivation in today's rapidly changing organizations. Drawing from psychology (social, clinical, and developmental) and social anthropology, the author develops propositions regarding the relationships between core confidence and performance, attitudes, and subjective well-being. The core confidence-higher order construct is proposed to be manifested by hope, self-efficacy, optimism, and resilience. The author reasons that these four variables share a common confidence core (a higher order construct) and may be considered as its manifestations. Suggestions for future research and implications of the work are discussed.

  19. Higher order microfibre modes for dielectric particle trapping and propulsion

    CERN Document Server

    Maimaiti, Aili; Sergides, Marios; Gusachenko, Ivan; Chormaic, Síle Nic

    2014-01-01

    Optical manipulation in the vicinity of optical micro- and nanofibres has shown potential across several fields in recent years, including microparticle control, and cold atom probing and trapping. To date, most work has focussed on propagation of the fundamental mode through the fibre. However, along the maximum mode intensity axis, higher order modes have a longer evanescent field extension and larger field amplitude at the fibre waist compared to the fundamental mode, opening up new possibilities for optical manipulation and particle trapping. In this work, we demonstrate a microfibre/optical tweezers compact system for trapping and propelling dielectric particles based on the excitation of the first group of higher order modes at the fibre waist. Single polystyrene particles were trapped and propelled in the evanescent fields of higher order and fundamental modes near the surface of microfibres. Speed enhancement of particle propulsion was observed for the higher order modes compared to the fundamental mo...

  20. On Doubly Degenerate Quasilinear Parabolic Equations of Higher Order

    Institute of Scientific and Technical Information of China (English)

    Zhen Hai LIU

    2005-01-01

    We deal with the existence of periodic solutions for doubly degenerate quasilinear parabolic equations of higher order, which can degenerate, on a part of the boundary, on a segment in the interior of the domain and in time.

  1. Feynman rules of higher-order poles in CHY construction

    Science.gov (United States)

    Huang, Rijun; Feng, Bo; Luo, Ming-xing; Zhu, Chuan-Jie

    2016-06-01

    In this paper, we generalize the integration rules for scattering equations to situations where higher-order poles are present. We describe the strategy to deduce the Feynman rules of higher-order poles from known analytic results of simple CHY-integrands, and propose the Feynman rules for single double pole and triple pole as well as duplex-double pole and triplex-double pole structures. We demonstrate the validation and strength of these rules by ample non-trivial examples.

  2. Higher order derivatives of R-Jacobi polynomials

    Science.gov (United States)

    Das, Sourav; Swaminathan, A.

    2016-06-01

    In this work, the R-Jacobi polynomials defined on the nonnegative real axis related to F-distribution are considered. Using their Sturm-Liouville system higher order derivatives are constructed. Orthogonality property of these higher ordered R-Jacobi polynomials are obtained besides their normal form, self-adjoint form and hypergeometric representation. Interesting results on the Interpolation formula and Gaussian quadrature formulae are obtained with numerical examples.

  3. Higher-Order Quantum-Inspired Genetic Algorithms

    OpenAIRE

    Nowotniak, Robert; Kucharski, Jacek

    2014-01-01

    This paper presents a theory and an empirical evaluation of Higher-Order Quantum-Inspired Genetic Algorithms. Fundamental notions of the theory have been introduced, and a novel Order-2 Quantum-Inspired Genetic Algorithm (QIGA2) has been presented. Contrary to all QIGA algorithms which represent quantum genes as independent qubits, in higher-order QIGAs quantum registers are used to represent genes strings which allows modelling of genes relations using quantum phenomena. Performance comparis...

  4. Higher order aberrations of the eye: Part one

    Directory of Open Access Journals (Sweden)

    Marsha Oberholzer

    2016-03-01

    Full Text Available This article is the first in a series of two articles that provide a comprehensive literature review of higher order aberrations (HOAs of the eye. The present article mainly explains the general principles of such HOAs as well as HOAs of importance, and the measuring apparatus used to measure HOAs of the eye. The second article in the series discusses factors contributing to variable results in measurements of HOAs of the eye.Keywords: Higher order aberrations; wavefront aberrations; aberrometer

  5. Linear matrix differential equations of higher-order and applications

    Directory of Open Access Journals (Sweden)

    Mustapha Rachidi

    2008-07-01

    Full Text Available In this article, we study linear differential equations of higher-order whose coefficients are square matrices. The combinatorial method for computing the matrix powers and exponential is adopted. New formulas representing auxiliary results are obtained. This allows us to prove properties of a large class of linear matrix differential equations of higher-order, in particular results of Apostol and Kolodner are recovered. Also illustrative examples and applications are presented.

  6. Slice Energy in Higher Order Gravity Theories and Conformal Transformations

    CERN Document Server

    Cotsakis, S

    2004-01-01

    We show that there is a generic transport of energy between the scalar field generated by the conformal transformation of higher order gravity theories and the matter component. We give precise relations of this exchange and show that, unless we are in a stationary spacetime, slice energy is not generically conserved. These results translate into statements about the relative behaviour of ordinary matter, dark matter and dark energy in the context of higher order gravity.

  7. Exploiting Higher-order Derivatives in Computational Optimal Control

    OpenAIRE

    Ross, I. Michael; Rea, Jeremy; Fahroo, Fariba

    2002-01-01

    Proceedings of the 10th Mediterranean Conference on Control and Automation -- MED 2002 , Lisbon, Portugal, July7 9-12, 2002 To facilitate generation of real-time solutions to nonlinear optimal control problems, we present a new way of approximating higher-order derivatives that arise in control systems. A Legendre pseudospectral method is presented to efficiently and accurately discretize optimal control problems governed by higher-order dynamical constraints. For mechanical systems, a re...

  8. Modeling of higher order systems using artificial bee colony algorithm

    Directory of Open Access Journals (Sweden)

    Aytekin Bağış

    2016-05-01

    Full Text Available In this work, modeling of the higher order systems based on the use of the artificial bee colony (ABC algorithm were examined. Proposed model parameters for the sample systems in the literature were obtained by using the algorithm, and its performance was presented comparatively with the other methods. Simulation results show that the ABC algorithm based system modeling approach can be used as an efficient and powerful method for higher order systems.

  9. All-fiber Raman Probe using Higher Order Modes

    DEFF Research Database (Denmark)

    Larsen, Stine Højer Møller; Rishøj, Lars Søgaard; Rottwitt, Karsten

    2013-01-01

    We demonstrate the first all-fiber Raman probe utilizing higher order modes for the excitation. The spectrum of cyclohexane is measured using both the fundamental mode as well as in-fiber-generated Bessel-like modes.......We demonstrate the first all-fiber Raman probe utilizing higher order modes for the excitation. The spectrum of cyclohexane is measured using both the fundamental mode as well as in-fiber-generated Bessel-like modes....

  10. Dual equivalence in models with higher-order derivatives

    CERN Document Server

    Bazeia, D; Nascimento, J R S; Ribeiro, R F; Wotzasek, C

    2003-01-01

    We introduce a class of higher-order derivative models in (2,1) space-time dimensions. The models are described by a vector field, and contain a Proca-like mass term which prevents gauge invariance. We use the gauge embedding procedure to generate another class of higher-order derivative models, gauge-invariant and dual to the former class. We also show that the gauge embedding approach works appropriately when the vector field couples with fermionic matter.

  11. Dynamics and control of higher-order nonholonomic systems

    Science.gov (United States)

    Rubio Hervas, Jaime

    A theoretical framework is established for the control of higher-order nonholonomic systems, defined as systems that satisfy higher-order nonintegrable constraints. A model for such systems is developed in terms of differential-algebraic equations defined on a higher-order tangent bundle. A number of control-theoretic properties such as nonintegrability, controllability, and stabilizability are presented. Higher-order nonholonomic systems are shown to be strongly accessible and, under certain conditions, small time locally controllable at any equilibrium. There are important examples of higher-order nonholonomic systems that are asymptotically stabilizable via smooth feedback, including space vehicles with multiple slosh modes and Prismatic-Prismatic-Revolute (PPR) robots moving open liquid containers, as well as an interesting class of systems that do not admit asymptotically stabilizing continuous static or dynamic state feedback. Specific assumptions are introduced to define this class, which includes important examples of robotic systems. A discontinuous nonlinear feedback control algorithm is developed to steer any initial state to the equilibrium at the origin. The applicability of the theoretical development is illustrated through two examples: control of a planar PPR robot manipulator subject to a jerk constraint and control of a point mass moving on a constant torsion curve in a three dimensional space.

  12. Higher-Order Factors of Personality: Do They Exist?

    Science.gov (United States)

    Ashton, Michael C.; Lee, Kibeom; Goldberg, Lewis R.; de Vries, Reinout E.

    2010-01-01

    Scales that measure the Big Five personality factors are often substantially intercorrelated. These correlations are sometimes interpreted as implying the existence of two higher-order factors of personality. We show that correlations between measures of broad personality factors do not necessarily imply the existence of higher-order factors, and might instead be due to variables that represent same-signed blends of orthogonal factors. Therefore, the hypotheses of higher-order factors and blended variables can only be tested with data on lower-level personality variables that define the personality factors. We compared the higher-order factor model and the blended variable model in three participant samples using the Big Five Aspect Scales, and found better fit for the latter model. In other analyses using the HEXACO Personality Inventory, we identified mutually uncorrelated markers of six personality factors. We conclude that correlations between personality factor scales can be explained without postulating any higher-order dimensions of personality. PMID:19458345

  13. Should evolutionary geneticists worry about higher-order epistasis?

    Science.gov (United States)

    Weinreich, Daniel M; Lan, Yinghong; Wylie, C Scott; Heckendorn, Robert B

    2013-12-01

    Natural selection drives evolving populations up the fitness landscape, the projection from nucleotide sequence space to organismal reproductive success. While it has long been appreciated that topographic complexities on fitness landscapes can arise only as a consequence of epistatic interactions between mutations, evolutionary genetics has mainly focused on epistasis between pairs of mutations. Here we propose a generalization to the classical population genetic treatment of pairwise epistasis that yields expressions for epistasis among arbitrary subsets of mutations of all orders (pairwise, three-way, etc.). Our approach reveals substantial higher-order epistasis in almost every published fitness landscape. Furthermore we demonstrate that higher-order epistasis is critically important in two systems we know best. We conclude that higher-order epistasis deserves empirical and theoretical attention from evolutionary geneticists.

  14. Stochastic Models for Phylogenetic Trees on Higher-order Taxa

    CERN Document Server

    Aldous, David; Popovic, Lea

    2007-01-01

    Simple stochastic models for phylogenetic trees on species have been well studied. But much paleontology data concerns time series or trees on higher-order taxa, and any broad picture of relationships between extant groups requires use of higher-order taxa. A coherent model for trees on (say) genera should involve both a species-level model and a model for the classification scheme by which species are assigned to genera. We present a general framework for such models, and describe three alternate classification schemes. Combining with the species-level model of Aldous-Popovic (2005), one gets models for higher-order trees, and we initiate analytic study of such models. In particular we derive formulas for the lifetime of genera, for the distribution of number of species per genus, and for the offspring structure of the tree on genera.

  15. Higher-order discrete variational problems with constraints

    Science.gov (United States)

    Colombo, Leonardo; Martín de Diego, David; Zuccalli, Marcela

    2013-09-01

    An interesting family of geometric integrators for Lagrangian systems can be defined using discretizations of the Hamilton's principle of critical action. This family of geometric integrators is called variational integrators. In this paper, we derive new variational integrators for higher-order Lagrangian mechanical system subjected to higher-order constraints. From the discretization of the variational principles, we show that our methods are automatically symplectic and, in consequence, with a very good energy behavior. Additionally, the symmetries of the discrete Lagrangian imply that momentum is conserved by the integrator. Moreover, we extend our construction to variational integrators where the Lagrangian is explicitly time-dependent. Finally, some motivating applications of higher-order problems are considered; in particular, optimal control problems for explicitly time-dependent underactuated systems and an interpolation problem on Riemannian manifolds.

  16. Higher-order modulation instability in nonlinear fiber optics.

    Science.gov (United States)

    Erkintalo, Miro; Hammani, Kamal; Kibler, Bertrand; Finot, Christophe; Akhmediev, Nail; Dudley, John M; Genty, Goëry

    2011-12-16

    We report theoretical, numerical, and experimental studies of higher-order modulation instability in the focusing nonlinear Schrödinger equation. This higher-order instability arises from the nonlinear superposition of elementary instabilities, associated with initial single breather evolution followed by a regime of complex, yet deterministic, pulse splitting. We analytically describe the process using the Darboux transformation and compare with experiments in optical fiber. We show how a suitably low frequency modulation on a continuous wave field induces higher-order modulation instability splitting with the pulse characteristics at different phases of evolution related by a simple scaling relationship. We anticipate that similar processes are likely to be observed in many other systems including plasmas, Bose-Einstein condensates, and deep water waves.

  17. Higher-order theories from the minimal length

    Science.gov (United States)

    Dias, M.; Hoff da Silva, J. M.; Scatena, E.

    2016-06-01

    We show that the introduction of a minimal length in the context of noncommutative space-time gives rise (after some considerations) to higher-order theories. We then explicitly demonstrate how these higher-derivative theories appear as a generalization of the standard electromagnetism and general relativity by applying a consistent procedure that modifies the original Maxwell and Einstein-Hilbert actions. In order to set a bound on the minimal length, we compare the deviations from the inverse-square law with the potentials obtained in the higher-order theories and discuss the validity of the results. The introduction of a quantum bound for the minimal length parameter β in the higher-order QED allows us to lower the actual limits on the parameters of higher-derivative gravity by almost half of their order of magnitude.

  18. Higher-order theories from the minimal length

    CERN Document Server

    Dias, Marco; Scatena, Eslley

    2016-01-01

    We show that the introduction of a minimal length in the context of non-commutative spacetime gives rise (after some considerations) to higher-order theories. We then explicitly demonstrate how these higher-derivative theories appear as a generalization of the standard electromagnetism and general relativity by applying a consistent procedure that modifies the original Maxwell and Einstein-Hilbert actions. In order to set a bound on the minimal length, we compare the deviations from the inverse-square law with the potentials obtained in the higher-order theories and discuss the validity of the results. The introduction of a quantum bound for the minimal length parameter $\\sqrt{\\beta}$ in the higher-order QED allows us to lower the actual limits on the parameters of higher-derivative gravity by almost half of their order of magnitude.

  19. Higher-order Kerr effect and harmonic cascading in gases

    CERN Document Server

    Bache, Morten; Minardi, Stefano

    2012-01-01

    The higher-order Kerr effect (HOKE) has been recently advocated to explain measurements of the saturation of the nonlinear refractive index in gases. Here we show that cascaded third-harmonic generation results in an effective fifth order nonlinearity that is negative and significant. Higher-order harmonic cascading will also occur from the HOKE, and the cascading contributions may significantly modify the observed nonlinear index change. At lower wavelengths cascading increases the HOKE saturation intensity, while for longer wavelengths cascading will decrease the HOKE saturation intensity.

  20. Detection of small target using recursive higher order statistics

    Science.gov (United States)

    Hou, Wang; Sun, Hongyuan; Lei, Zhihui

    2014-02-01

    In this paper, a recursive higher order statistics algorithm is proposed for small target detection in temporal domain. Firstly, the background of image sequence is normalized. Then, the higher order statistics are recursively solved in image sequence to obtain the feature image. Finally, the feature image is segmented with threshold to detect the small target. To validate the algorithm proposed in this paper, five simulated and one semi-simulation image sequences are created. The ROC curves are employed for evaluation of experimental results. Experiment results show that our method is very effective for small target detection.

  1. Scintillations of higher order laser beams in anisotropic atmospheric turbulence.

    Science.gov (United States)

    Baykal, Yahya; Luo, Yujuan; Ji, Xiaoling

    2016-11-20

    The scintillation index of higher order laser beams is examined when such beams propagate in anisotropic atmospheric turbulence. Anisotropy is introduced through non-Kolmogorov atmospheric turbulence. The scintillation index results are obtained by employing the Rytov method solution; thus the results are valid for weak anisotropic atmospheric turbulence and for horizontal links. Variations in the scintillations are shown for various higher order laser modes against the changes in the optical source size, power law exponent of anisotropic non-Kolmogorov spectrum, anisotropic factors, and link length. Our results can be used in the design of optical wireless communication systems used between airplanes.

  2. Summation of Higher Order Effects using the Renormalization Group Equation

    CERN Document Server

    Elias, V; Sherry, T N

    2004-01-01

    The renormalization group (RG) is known to provide information about radiative corrections beyond the order in perturbation theory to which one has calculated explicitly. We first demonstrate the effect of the renormalization scheme used on these higher order effects determined by the RG. Particular attention is payed to the relationship between bare and renormalized quantities. Application of the method of characteristics to the RG equation to determine higher order effects is discussed, and is used to examine the free energy in thermal field theory, the relationship between the bare and renormalized coupling and the effective potential in massless scalar electrodynamics.

  3. Higher-order Laplace equations and hyper-Cauchy distributions

    CERN Document Server

    Orsingher, Enzo

    2012-01-01

    In this paper we introduce new distributions which are solutions of higher-order Laplace equations. It is proved that their densities can be obtained by folding and symmetrizing Cauchy distributions. Another class of probability laws related to higher-order Laplace equations is obtained by composing pseudo-processes with positively-skewed Cauchy distributions which produce asymmetric Cauchy densities in the odd-order case. A special attention is devoted to the third-order Laplace equation where the connection between the Cauchy distribution and the Airy functions is obtained and analyzed.

  4. Interference of selective higher-order modes in optical fibers

    Institute of Scientific and Technical Information of China (English)

    Li Enbang; Peng Gangding

    2007-01-01

    The interference of selective higher-order modes in optical fibers is investigated both theoretically and experimentally.It has been demonstrated that by coupling the LP01 mode in a step-index single-mode fiber(SMF)to the LPom modes in step-index muhimode fibers(MMFs)with different parameters,one can selectively generate higher-order modes and construct all-fiber interferometers.The research presented in this paper forms a basis of a new type of fiber devices with potential applications in fiber sensing,optical fiber communications,and optical signal processing.

  5. Higher order nonlinearity and synchronization of quantum cascade lasers

    Institute of Scientific and Technical Information of China (English)

    Taraprasad Chattopadhyay; Prosenjit Bhattacharyya

    2011-01-01

    This paper presents a closed-form analysis of the synchronization phenomenon of the quantum cascade laser (QCL). The analysis has been made with considering higher order nonlinearity of the modal gain of the QCL. The frequency response characteristics of the synchronized QCL along with the stability of the locked state, the effect of nonlinearity on the lockband of the QCL and the amplitude limiting action of the locked QCL have been calculated. The analysis demonstrates the effect of higher order nonlinearity on the properties of the synchronized QCL.

  6. The Cauchy problem for higher order abstract differential equations

    CERN Document Server

    Xiao, Ti-Jun

    1998-01-01

    This monograph is the first systematic exposition of the theory of the Cauchy problem for higher order abstract linear differential equations, which covers all the main aspects of the developed theory. The main results are complete with detailed proofs and established recently, containing the corresponding theorems for first and incomplete second order cases and therefore for operator semigroups and cosine functions. They will find applications in many fields. The special power of treating the higher order problems directly is demonstrated, as well as that of the vector-valued Laplace transforms in dealing with operator differential equations and operator families. The reader is expected to have a knowledge of complex and functional analysis.

  7. Implementation of higher-order absorbing boundary conditions for the Einstein equations

    CERN Document Server

    Rinne, Oliver; Scheel, Mark A; Pfeiffer, Harald P

    2008-01-01

    We present an implementation of absorbing boundary conditions for the Einstein equations based on the recent work of Buchman and Sarbach. In this paper, we assume that spacetime may be linearized about Minkowski space close to the outer boundary, which is taken to be a coordinate sphere. We reformulate the boundary conditions as conditions on the gauge-invariant Regge-Wheeler-Zerilli scalars. Higher-order radial derivatives are eliminated by rewriting the boundary conditions as a system of ODEs for a set of auxiliary variables intrinsic to the boundary. From these we construct boundary data for a set of well-posed constraint-preserving boundary conditions for the Einstein equations in a first-order generalized harmonic formulation. This construction has direct applications to outer boundary conditions in simulations of isolated systems (e.g., binary black holes) as well as to the problem of Cauchy-perturbative matching. As a test problem for our numerical implementation, we consider linearized multipolar grav...

  8. Extracting the jet azimuthal anisotropy from higher order cumulants

    CERN Document Server

    Lokhtin, Igor P; Snigirev, A M

    2003-01-01

    We analyze the method for calculation of a coefficient of jet azimuthal anisotropy without reconstruction of the nuclear reaction plane considering the higher order correlators between the azimuthal position of jet axis and the angles of particles not incorporated in the jet. The reliability of this technique in the real physical situation under LHC conditions is illustrated.

  9. Decidable Fragments of a Higher Order Calculus with Locations

    DEFF Research Database (Denmark)

    Hüttel, Hans; Godskesen, Jens Christian; Haagensen, Bjørn

    2009-01-01

    Homer is a higher order process calculus with locations. In this paper we study Homer in the setting of the semantic finite control property, which is a finite reachability criterion that implies decidability of barbed bisimilarity. We show that strong and weak barbed bisimilarity are undecidable...... control π-calculus in Homer....

  10. Higher Order Risk Attitudes, Demographics, and Financial Decisions

    NARCIS (Netherlands)

    Noussair, C.N.; Trautmann, S.T.; van de Kuilen, G.

    2011-01-01

    We conduct an experiment to study the prevalence of the higher order risk attitudes of prudence and temperance, in a large demographically representative sample, as well as in a sample of undergraduate students. Participants make pairwise choices between lotteries of the form proposed by Eeckhoudt a

  11. Higher-Order Hierarchical Legendre Basis Functions in Applications

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Jørgensen, Erik; Meincke, Peter;

    2007-01-01

    degree of orthogonality. The basis functions are well-suited for solution of complex electromagnetic problems involving multiple homogeneous or inhomogeneous dielectric regions, metallic surfaces, layered media, etc. This paper presents real-life complex antenna radiation problems modeled...... with electromagnetic simulation tools based on the higher-order hierarchical Legendre basis functions....

  12. Enhancing Higher Order Thinking Skills through Clinical Simulation

    Science.gov (United States)

    Varutharaju, Elengovan; Ratnavadivel, Nagendralingan

    2014-01-01

    Purpose: The study aimed to explore, describe and analyse the design and implementation of clinical simulation as a pedagogical tool in bridging the deficiency of higher order thinking skills among para-medical students, and to make recommendations on incorporating clinical simulation as a pedagogical tool to enhance thinking skills and align the…

  13. Heat polynomial analogs for higher order evolution equations

    Directory of Open Access Journals (Sweden)

    G. N. Hile

    2001-05-01

    Full Text Available Polynomial solutions analogous to the heat polynomials are demonstrated for higher order linear homogeneous evolution equations with coefficients depending on the time variable. Further parallels with the heat polynomials are established when the equation is parabolic with constant coefficients and only highest order terms.

  14. Multilevel Fast Multipole Method for Higher Order Discretizations

    DEFF Research Database (Denmark)

    Borries, Oscar Peter; Meincke, Peter; Jorgensen, Erik;

    2014-01-01

    The multi-level fast multipole method (MLFMM) for a higher order (HO) discretization is demonstrated on high-frequency (HF) problems, illustrating for the first time how an efficient MLFMM for HO can be achieved even for very large groups. Applying several novel ideas, beneficial to both lower or...

  15. Impulse Controllability : From Descriptor Systems to Higher Order DAEs

    NARCIS (Netherlands)

    Kalpana Kalaimani, Rachel; Praagman, Cornelis; Belur, Madhu N.

    2016-01-01

    Impulsive solutions in LTI dynamical systems have received ample attention, but primarily for descriptor systems, i.e., first order Differential Algebraic Equations (DAEs). This paper focuses on the impulsive behavior of higher order dynamical systems and analyzes the causes of impulses in the conte

  16. The structured controllability radii of higher order systems

    National Research Council Canada - National Science Library

    Son, Nguyen Khoa; Thuan, Do Duc

    2013-01-01

    In this paper we shall deal with the problem of calculation of the controllability radius of higher order dynamical systems of the form Ex.sup.(k)(t)=A.sub.k-1x.sup.(k-1)(t)+a[macron]+A.sub.1x.sup.(1)(t)+A.sub.0x(t)+Bu...

  17. Higher Order Language Competence and Adolescent Mental Health

    Science.gov (United States)

    Cohen, Nancy J.; Farnia, Fataneh; Im-Bolter, Nancie

    2013-01-01

    Background: Clinic and community-based epidemiological studies have shown an association between child psychopathology and language impairment. The demands on language for social and academic adjustment shift dramatically during adolescence and the ability to understand the nonliteral meaning in language represented by higher order language…

  18. Meta-Logical Reasoning in Higher-Order Logic

    DEFF Research Database (Denmark)

    Villadsen, Jørgen; Schlichtkrull, Anders; Hess, Andreas Viktor

    The semantics of first-order logic (FOL) can be described in the meta-language of higher-order logic (HOL). Using HOL one can prove key properties of FOL such as soundness and completeness. Furthermore, one can prove sentences in FOL valid using the formalized FOL semantics. To aid in the constru...

  19. RECURSIVE CLASSIFICATION OF MQAM SIGNALS BASED ON HIGHER ORDER CUMULANTS

    Institute of Scientific and Technical Information of China (English)

    Chen Weidong; Yang Shaoquan

    2002-01-01

    A new feature based on higher order cumulants is proposed for classification of MQAM signals. Theoretical analysis justify that the new feature is invariant with respect to translation (shift), scale and rotation transform of signal constellations, and can suppress color or white additive Gaussian noise. Computer simulation shows that the proposed recursive orderreduction based classification algorithm can classify MQAM signals with any order.

  20. Higher order Fano graphene metamaterials for nanoscale optical sensing.

    Science.gov (United States)

    Guo, Xiangdong; Hu, Hai; Zhu, Xing; Yang, Xiaoxia; Dai, Qing

    2017-09-28

    Plasmonic Fano metamaterials provide a unique platform for optical sensing applications due to their sharp spectral response and the ability to confine light to nanoscale regions that make them a strong prospect for refractive-index sensing. Higher order Fano resonance modes in noble metal plasmonic structures can further improve the sensitivity, but their applications are heavily limited by crosstalk between different modes due to the large damping rates and broadband spectral responses of the metal plasmon modes. Here, we create pure higher order Fano modes by designing asymmetric metamaterials comprised of a split-ring resonator and disk with a low-loss graphene plasmon. These higher order modes are highly sensitive to the nanoscale analyte (8 nm thick) both in refractive-index and in infrared vibrational fingerprint sensing, as demonstrated by the numerical calculation. The frequency sensitivity and figure-of-merit of the hexacontatetrapolar mode can reach 289 cm(-1) per RIU and 29, respectively, and it can probe the weak infrared vibrational modes of the analyte with more than 400 times enhancement. The enhanced sensitivity and tunability of higher order Fano graphene metamaterials promise a high-performance nanoscale optical sensor.

  1. The Role of Formative Feedback in Promoting Higher Order ...

    African Journals Online (AJOL)

    DrNneka

    can promote higher order thinking skills in the classroom. The proposed theoretical ... known predictable, well-known approach or pathway explicitly suggested by the task, ... problems, and enhancing open-ended group work and class discussions, there is a high ..... Journal of Research in Mathematics Education, 28(5),.

  2. Higher-Order Item Response Models for Hierarchical Latent Traits

    Science.gov (United States)

    Huang, Hung-Yu; Wang, Wen-Chung; Chen, Po-Hsi; Su, Chi-Ming

    2013-01-01

    Many latent traits in the human sciences have a hierarchical structure. This study aimed to develop a new class of higher order item response theory models for hierarchical latent traits that are flexible in accommodating both dichotomous and polytomous items, to estimate both item and person parameters jointly, to allow users to specify…

  3. Higher-order structure of rRNA

    Science.gov (United States)

    Gutell, R. R.; Woese, C. R.

    1986-01-01

    A comparative search for phylogenetically covarying basepair replacements within potential helices has been the only reliable method to determine the correct secondary structure of the 3 rRNAs, 5S, 16S, and 23S. The analysis of 16S from a wide phylogenetic spectrum, that includes various branches of the eubacteria, archaebacteria, eucaryotes, in addition to the mitochondria and chloroplast, is beginning to reveal the constraints on the secondary structures of these rRNAs. Based on the success of this analysis, and the assumption that higher order structure will also be phylogenetically conserved, a comparative search was initiated for positions that show co-variation not involved in secondary structure helices. From a list of potential higher order interactions within 16S rRNA, two higher-order interactions are presented. The first of these interactions involves positions 570 and 866. Based on the extent of phylogenetic covariation between these positions while maintaining Watson-Crick pairing, this higher-order interaction is considered proven. The other interaction involves a minimum of six positions between the 1400 and 1500 regions of the 16S rRNA. Although these patterns of covariation are not as striking as the 570/866 interaction, the fact that they all exist in an anti-parallel fashion and that experimental methods previously implicated these two regions of the molecule in tRNA function suggests that these interactions be given serious consideration.

  4. Generating superpositions of higher order bessel beams [Conference paper

    CSIR Research Space (South Africa)

    Vasilyeu, R

    2009-10-01

    Full Text Available of Higher Order Bessel Beams R. Vasilyeu1, A. Dudley2,3, N. Khilo1, and A. Forbes2,3 1 B.I. Stepanov Institute of Physics of NAS of Belarus, Nezalezhnasti Ave., 68, 220072 Minsk, Belarus r.vasilyev@dragon.bas-net.by and n.khilo@dragon.bas-net.by 2...

  5. Building Higher-Order Markov Chain Models with EXCEL

    Science.gov (United States)

    Ching, Wai-Ki; Fung, Eric S.; Ng, Michael K.

    2004-01-01

    Categorical data sequences occur in many applications such as forecasting, data mining and bioinformatics. In this note, we present higher-order Markov chain models for modelling categorical data sequences with an efficient algorithm for solving the model parameters. The algorithm can be implemented easily in a Microsoft EXCEL worksheet. We give a…

  6. Higher-Order Coloured Unification and Natural Language Semantics

    CERN Document Server

    Gardent, C; Gardent, Claire; Kohlhase, Michael

    1996-01-01

    In this paper, we show that Higher-Order Coloured Unification - a form of unification developed for automated theorem proving - provides a general theory for modeling the interface between the interpretation process and other sources of linguistic, non semantic information. In particular, it provides the general theory for the Primary Occurrence Restriction which (Dalrymple, Shieber and Pereira, 1991)'s analysis called for.

  7. First Measurements of Higher Order Optics Parameters in the LHC

    CERN Document Server

    Vanbavinckhove, G; Bartolini, R; Calaga, R; Giovannozzi, M; Maclean, E H; Miyamoto, R; Schmidt, F; Tomas, R

    2011-01-01

    Higher order effects can play an important role in the performance of the LHC. Lack of knowledge of these pa- rameters can increase the tune footprint and compromise the beam lifetime. First measurements of these parameters at injection and flattop have been conducted. Detailed sim- ulations are compared to the measurements together with discussions on the measurement limitations.

  8. Higher-order momentum distributions and locally affine LDDMM registration

    DEFF Research Database (Denmark)

    Sommer, Stefan Horst; Nielsen, Mads; Darkner, Sune;

    2013-01-01

    higher-order momentum distributions in the large deformation diffeomorphic metric mapping (LDDMM) registration framework. While the zeroth-order moments previously used in LDDMM only describe local displacement, the first-order momenta that are proposed here represent a basis that allows local...

  9. Abstract Operators and Higher-order Linear Partial Differential Equation

    Institute of Scientific and Technical Information of China (English)

    BI Guang-qing; BI Yue-kai

    2011-01-01

    We summarize several relevant principles for the application of abstract operators in partial differential equations,and combine abstract operators with the Laplace transform.Thus we have developed the theory of partial differential equations of abstract operators and obtained the explicit solutions of initial value problems for a class of higher-order linear partial differential equations.

  10. Numerical modeling of higher order magnetic moments in UXO discrimination

    Science.gov (United States)

    Sanchez, V.; Yaoguo, L.; Nabighian, M.N.; Wright, D.L.

    2008-01-01

    The surface magnetic anomaly observed in unexploded ordnance (UXO) clearance is mainly dipolar, and consequently, the dipole is the only magnetic moment regularly recovered in UXO discrimination. The dipole moment contains information about the intensity of magnetization but lacks information about the shape of the target. In contrast, higher order moments, such as quadrupole and octupole, encode asymmetry properties of the magnetization distribution within the buried targets. In order to improve our understanding of magnetization distribution within UXO and non-UXO objects and to show its potential utility in UXO clearance, we present a numerical modeling study of UXO and related metallic objects. The tool for the modeling is a nonlinear integral equation describing magnetization within isolated compact objects of high susceptibility. A solution for magnetization distribution then allows us to compute the magnetic multipole moments of the object, analyze their relationships, and provide a depiction of the anomaly produced by different moments within the object. Our modeling results show the presence of significant higher order moments for more asymmetric objects, and the fields of these higher order moments are well above the noise level of magnetic gradient data. The contribution from higher order moments may provide a practical tool for improved UXO discrimination. ?? 2008 IEEE.

  11. Higher-Order Integral Equation Methods in Computational Electromagnetics

    DEFF Research Database (Denmark)

    Jørgensen, Erik; Meincke, Peter

    Higher-order integral equation methods have been investigated. The study has focused on improving the accuracy and efficiency of the Method of Moments (MoM) applied to electromagnetic problems. A new set of hierarchical Legendre basis functions of arbitrary order is developed. The new basis...

  12. Improved Multilevel Fast Multipole Method for Higher-Order discretizations

    DEFF Research Database (Denmark)

    Borries, Oscar Peter; Meincke, Peter; Jorgensen, Erik

    2014-01-01

    The Multilevel Fast Multipole Method (MLFMM) allows for a reduced computational complexity when solving electromagnetic scattering problems. Combining this with the reduced number of unknowns provided by Higher-Order discretizations has proven to be a difficult task, with the general conclusion b...

  13. Higher order QCD corrections in small x physics

    Energy Technology Data Exchange (ETDEWEB)

    Chachamis, G.

    2006-11-15

    We study higher order QCD corrections in small x Physics. The numerical implementation of the full NLO photon impact factor is the remaining necessary piece for the testing of the NLO BFKL resummation against data from physical processes, such as {gamma}{sup *}{gamma}{sup *} collisions. We perform the numerical integration over phase space for the virtual corrections to the NLO photon impact factor. This, along with the previously calculated real corrections, makes feasible in the near future first estimates for the {gamma}*{gamma}* total cross section, since the convolution of the full impact factor with the NLO BFKL gluon Green's function is now straightforward. The NLO corrections for the photon impact factor are sizeable and negative. In the second part of this thesis, we estimate higher order correction to the BK equation. We are mainly interested in whether partonic saturation delays or not in rapidity when going beyond the leading order. In our investigation, we use the so called 'rapidity veto' which forbid two emissions to be very close in rapidity, to 'switch on' higher order corrections to the BK equation. From analytic and numerical analysis, we conclude that indeed saturation does delay in rapidity when higher order corrections are taken into account. In the last part, we investigate higher order QCD corrections as additional corrections to the Electroweak (EW) sector. The question of whether BFKL corrections are of any importance in the Regge limit for the EW sector seems natural; although they arise in higher loop level, the accumulation of logarithms in energy s at high energies, cannot be dismissed without an investigation. We focus on the process {gamma}{gamma}{yields}ZZ. We calculate the pQCD corrections in the forward region at leading logarithmic (LL) BFKL accuracy, which are of the order of few percent at the TeV energy scale. (orig.)

  14. Medical Data Transformation Using Rewriting

    Directory of Open Access Journals (Sweden)

    Naveen eAshish

    2015-02-01

    Full Text Available This paper presents an approach to and system for declaratively transforming medical subjects’ data into a common data model representation. Our work is part of the GAAIN project on Alzheimer’s disease data federation. We present a general purpose data transformation system that we have developed by leveraging the existing state-of-the-art in data integration and query rewriting. In this work we have further extended the current technology with new formalisms that facilitate expressing a broader range of data transformation tasks, plus new execution methodologies to ensure efficient data transformation for disease datasets.

  15. The Application of Rewriting in Cultural Transfer

    Institute of Scientific and Technical Information of China (English)

    赵敏洁

    2016-01-01

    In the context of globalization, cultural exchange is frequently conducted between countries in translating activities. Comparing with linguistic transfer, cultural transfer is frequented applied as to achieve communicative equivalence. Studies of rewriting applied as a method of cultural translation from Chinese to English are still relatively weak in the field of translation in China. Exclusive research on the methods for cultural translation is still uncompleted. In the last decade, when comes to cultural elements in translation, methods as restoring sounds, adding extra explanation, or detecting equivalent concepts have been most-ly discussed, but rewriting is rarely involved in it. This thesis reviews previous definitions for rewriting or adaptation;analyses the difference between linguistic transfer and cultural transfer, and why rewriting is adopted as an effective method for cultural translation;the application of rewriting will break up the dominance of occidental culture in the world while make oriental cul-ture become influential in the western world.

  16. Higher Order Kernels and Locally Affine LDDMM Registration

    CERN Document Server

    Sommer, Stefan; Darkner, Sune; Pennec, Xavier

    2011-01-01

    To achieve sparse description that allows intuitive analysis, we aim to represent deformation with a basis containing interpretable elements, and we wish to use elements that have the description capacity to represent the deformation compactly. We accomplish this by introducing higher order kernels in the LDDMM registration framework. The kernels allow local description of affine transformations and subsequent compact description of non-translational movement and of the entire non-rigid deformation. This is obtained with a representation that contains directly interpretable information from both mathematical and modeling perspectives. We develop the mathematical construction behind the higher order kernels, we show the implications for sparse image registration and deformation description, and we provide examples of how the capacity of the kernels enables registration with a very low number of parameters. The capacity and interpretability of the kernels lead to natural modeling of articulated movement, and th...

  17. Higher order theories and their relationship with noncommutativity

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez-Santos, Oscar, E-mail: oscarsanbuzz@yahoo.com.mx [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, San Rafael Atlixco 186, C.P. 09340, México D.F., México (Mexico); Vergara, José David, E-mail: vergara@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apartado Postal 70-543, C.P. 04510, México D.F., México (Mexico)

    2014-06-13

    We present a relationship between noncommutativity and higher order time derivative theories using a perturbation method. We make a generalization of the Chern–Simons quantum mechanics for higher order time derivatives. This model presents noncommutativity in a natural way when we project to low-energy physical states without the necessity of taking the strong field limit. We quantize the theory using a Bopp's shift of the noncommutative variables and we obtain a spectrum without negative energies, under the perturbation limits. In addition, we extent the model to high order time derivatives and noncommutativity with variable dependent parameter. - Highlights: • We show a relationship between high order derivative theories and noncommutativity. • The noncommutativity appears when we project to low-energy physical states. • We extend the model to high order time derivatives. • We include cases with variable dependent noncommutative parameter.

  18. Higher order gravity theories and their black hole solutions

    CERN Document Server

    Charmousis, Christos

    2008-01-01

    We discuss a particular higher order gravity theory, Lovelock theory, that generalises in higher dimensions, general relativity. After briefly motivating modifications of gravity, we will introduce the theory in question and we will argue that it is a unique, mathematically sensible, and physically interesting extension of general relativity. We will see, by using the formalism of differential forms, the relation of Lovelock gravity to differential geometry and topology of even dimensional manifolds. We will then discuss a generic staticity theorem, which will give us the charged static black hole solutions. We will examine their asymptotic behavior, analyse their horizon structure and briefly their thermodynamics. We will then examine the distributional matching conditions for Lovelock theory. We will see how induced 4 dimensional Einstein-Hilbert terms result on the brane geometry from the higher order Lovelock terms. With the junction conditions at hand, we will go back to the black hole solutions and give...

  19. An Algorithm for Higher Order Hopf Normal Forms

    Directory of Open Access Journals (Sweden)

    A.Y.T. Leung

    1995-01-01

    Full Text Available Normal form theory is important for studying the qualitative behavior of nonlinear oscillators. In some cases, higher order normal forms are required to understand the dynamic behavior near an equilibrium or a periodic orbit. However, the computation of high-order normal forms is usually quite complicated. This article provides an explicit formula for the normalization of nonlinear differential equations. The higher order normal form is given explicitly. Illustrative examples include a cubic system, a quadratic system and a Duffing–Van der Pol system. We use exact arithmetic and find that the undamped Duffing equation can be represented by an exact polynomial differential amplitude equation in a finite number of terms.

  20. Comparison Criteria for Nonlinear Functional Dynamic Equations of Higher Order

    Directory of Open Access Journals (Sweden)

    Taher S. Hassan

    2016-01-01

    Full Text Available We will consider the higher order functional dynamic equations with mixed nonlinearities of the form xnt+∑j=0Npjtϕγjxφjt=0, on an above-unbounded time scale T, where n≥2, xi(t≔ri(tϕαixi-1Δ(t,  i=1,…,n-1,   with  x0=x,  ϕβ(u≔uβsgn⁡u, and α[i,j]≔αi⋯αj. The function φi:T→T is a rd-continuous function such that limt→∞φi(t=∞ for j=0,1,…,N. The results extend and improve some known results in the literature on higher order nonlinear dynamic equations.

  1. Speckle reduction via higher order total variation approach.

    Science.gov (United States)

    Wensen Feng; Hong Lei; Yang Gao

    2014-04-01

    Multiplicative noise (also known as speckle) reduction is a prerequisite for many image-processing tasks in coherent imaging systems, such as the synthetic aperture radar. One approach extensively used in this area is based on total variation (TV) regularization, which can recover significantly sharp edges of an image, but suffers from the staircase-like artifacts. In order to overcome the undesirable deficiency, we propose two novel models for removing multiplicative noise based on total generalized variation (TGV) penalty. The TGV regularization has been mathematically proven to be able to eliminate the staircasing artifacts by being aware of higher order smoothness. Furthermore, an efficient algorithm is developed for solving the TGV-based optimization problems. Numerical experiments demonstrate that our proposed methods achieve state-of-the-art results, both visually and quantitatively. In particular, when the image has some higher order smoothness, our methods outperform the TV-based algorithms.

  2. Statistics of predictions with missing higher order corrections

    CERN Document Server

    Berthier, Laure

    2016-01-01

    Effective operators have been used extensively to understand small deviations from the Standard Model in the search for new physics. So far there has been no general method to fit for small parameters when higher order corrections in these parameters are present but unknown. We present a new technique that solves this problem, allowing for an exact p-value calculation under the assumption that higher order theoretical contributions can be treated as gaussian distributed random variables. The method we propose is general, and may be used in the analysis of any perturbative theoretical prediction, ie.~truncated power series. We illustrate this new method by performing a fit of the Standard Model Effective Field Theory parameters, which include eg.~anomalous gauge and four-fermion couplings.

  3. Higher order moments of lensing convergence - I. Estimate from simulations

    CERN Document Server

    Vicinanza, M; Maoli, R; Scaramella, R; Er, X

    2016-01-01

    Large area lensing surveys are expected to make it possible to use cosmic shear tomography as a tool to severely constrain cosmological parameters. To this end, one typically relies on second order statistics such as the two - point correlation fucntion and its Fourier counterpart, the power spectrum. Moving a step forward, we wonder whether and to which extent higher order stastistics can improve the lensing Figure of Merit (FoM). In this first paper of a series, we investigate how second, third and fourth order lensing convergence moments can be measured and use as probe of the underlying cosmological model. We use simulated data and investigate the impact on moments estimate of the map reconstruction procedure, the cosmic variance, and the intrinsic ellipticity noise. We demonstrate that, under realistic assumptions, it is indeed possible to use higher order moments as a further lensing probe.

  4. Toddlers infer higher-order relational principles in causal learning.

    Science.gov (United States)

    Walker, Caren M; Gopnik, Alison

    2014-01-01

    Children make inductive inferences about the causal properties of individual objects from a very young age. When can they infer higher-order relational properties? In three experiments, we examined 18- to 30-month-olds' relational inferences in a causal task. Results suggest that at this age, children are able to infer a higher-order relational causal principle from just a few observations and use this inference to guide their own subsequent actions and bring about a novel causal outcome. Moreover, the children passed a revised version of the relational match-to-sample task that has proven very difficult for nonhuman primates. The findings are considered in light of their implications for understanding the nature of relational and causal reasoning, and their evolutionary origins.

  5. Promoting higher order thinking skills using inquiry-based learning

    Science.gov (United States)

    Madhuri, G. V.; S. S. N Kantamreddi, V.; Goteti, L. N. S. Prakash

    2012-05-01

    Active learning pedagogies play an important role in enhancing higher order cognitive skills among the student community. In this work, a laboratory course for first year engineering chemistry is designed and executed using an inquiry-based learning pedagogical approach. The goal of this module is to promote higher order thinking skills in chemistry. Laboratory exercises are designed based on Bloom's taxonomy and a just-in-time facilitation approach is used. A pre-laboratory discussion outlining the theory of the experiment and its relevance is carried out to enable the students to analyse real-life problems. The performance of the students is assessed based on their ability to perform the experiment, design new experiments and correlate practical utility of the course module with real life. The novelty of the present approach lies in the fact that the learning outcomes of the existing experiments are achieved through establishing a relationship with real-world problems.

  6. Higher order relativistic galaxy number counts: dominating terms

    CERN Document Server

    Nielsen, Jeppe Trøst

    2016-01-01

    We review the number counts to second order concentrating on the terms which dominate on sub horizon scales. We re-derive the result for these terms and compare it with the different versions found in the literature. We generalize our derivation to higher order terms, especially the third order number counts which are needed to compute the 1-loop contribution to the power spectrum.

  7. 1957-2007: 50 Years of Higher Order Programming Languages

    OpenAIRE

    Alen Lovrenčić; Mario Konecki; Tihomir Orehovački

    2009-01-01

    Fifty years ago one of the greatest breakthroughs in computer programming and in the history of computers happened -- the appearance of FORTRAN, the first higher-order programming language. From that time until now hundreds of programming languages were invented, different programming paradigms were defined, all with the main goal to make computer programming easier and closer to as many people as possible. Many battles were fought among scientists as well as among developers around concepts ...

  8. Graph rewriting with polarized cloning

    CERN Document Server

    Duval, Dominique; Prost, Frédéric

    2009-01-01

    We tackle the problem of graph transformation with a particular focus on node cloning. We propose a graph rewriting framework where nodes can be cloned zero, one or more times. A node can be cloned together with all its incident edges, with only the outgoing edges, with only the incoming edges or without any of the incident edges. We thus subsume previous works such as the sesqui-pushout, the heterogeneous pushout and the adaptive star grammars approaches. A rule is defined as a span $\\spa{\\grpol{L}}{l}{\\grpol{K}}{r}{R}$ where the right-hand side $R$ is a multigraph, the left-hand side $\\grpol{L}$ and the interface $\\grpol{K}$ are polarized multigraphs. A polarized multigraph is a multigraph endowed with some cloning annotations on nodes and edges. We introduce the notion of polarized multigraphs and define a rewriting step as pushback followed by a pushout in the same way as in the sesqui-pushout approach.

  9. Wave Transformation Modeling with Effective Higher-Order Finite Elements

    Directory of Open Access Journals (Sweden)

    Tae-Hwa Jung

    2016-01-01

    Full Text Available This study introduces a finite element method using a higher-order interpolation function for effective simulations of wave transformation. Finite element methods with a higher-order interpolation function usually employ a Lagrangian interpolation function that gives accurate solutions with a lesser number of elements compared to lower order interpolation function. At the same time, it takes a lot of time to get a solution because the size of the local matrix increases resulting in the increase of band width of a global matrix as the order of the interpolation function increases. Mass lumping can reduce computation time by making the local matrix a diagonal form. However, the efficiency is not satisfactory because it requires more elements to get results. In this study, the Legendre cardinal interpolation function, a modified Lagrangian interpolation function, is used for efficient calculation. Diagonal matrix generation by applying direct numerical integration to the Legendre cardinal interpolation function like conducting mass lumping can reduce calculation time with favorable accuracy. Numerical simulations of regular, irregular and solitary waves using the Boussinesq equations through applying the interpolation approaches are carried out to compare the higher-order finite element models on wave transformation and examine the efficiency of calculation.

  10. Higher-order conditioning and the retrosplenial cortex.

    Science.gov (United States)

    Todd, Travis P; Huszár, Roman; DeAngeli, Nicole E; Bucci, David J

    2016-09-01

    The retrosplenial cortex (RSC) is known to contribute to contextual and spatial learning and memory. This is consistent with its well-established connectivity; the RSC is located at the interface of visuo-spatial association areas and the parahippocampal-hippocampal memory system. However, the RSC also contributes to learning and memory for discrete cues. For example, both permanent lesions and temporary inactivation of the RSC have been shown to impair sensory preconditioning, a form of higher-order conditioning. The purpose of the present experiment was to examine the role of the RSC in a closely related higher-order conditioning paradigm: second-order conditioning. Sham and RSC lesioned rats received first-order conditioning in which one visual stimulus (V1) was paired with footshock and one visual stimulus (V2) was not. Following first-order conditioning, one auditory stimulus (A1) was then paired with V1 and a second auditory stimulus (A2) was paired with V2. Although lesions of the RSC impaired the first-order discrimination, they had no impact on the acquisition of second-order conditioning. Thus, the RSC does not appear necessary for acquisition/expression of second-order fear conditioning. The role of the RSC in higher-order conditioning, as well as a possible dissociation from the hippocampus, is discussed.

  11. Transversely isotropic higher-order averaged structure tensors

    Science.gov (United States)

    Hashlamoun, Kotaybah; Federico, Salvatore

    2017-08-01

    For composites or biological tissues reinforced by statistically oriented fibres, a probability distribution function is often used to describe the orientation of the fibres. The overall effect of the fibres on the material response is accounted for by evaluating averaging integrals over all possible directions in space. The directional average of the structure tensor (tensor product of the unit vector describing the fibre direction by itself) is of high significance. Higher-order averaged structure tensors feature in several models and carry similarly important information. However, their evaluation has a quite high computational cost. This work proposes to introduce mathematical techniques to minimise the computational cost associated with the evaluation of higher-order averaged structure tensors, for the case of a transversely isotropic probability distribution of orientation. A component expression is first introduced, using which a general tensor expression is obtained, in terms of an orthonormal basis in which one of the vectors coincides with the axis of symmetry of transverse isotropy. Then, a higher-order transversely isotropic averaged structure tensor is written in an appropriate basis, constructed starting from the basis of the space of second-order transversely isotropic tensors, which is constituted by the structure tensor and its complement to the identity.

  12. Higher Order Mode Coupler Heating in Continuous Wave Operation

    Science.gov (United States)

    Solyak, N.; Awida, M.; Hocker, A.; Khabibobulline, T.; Lunin, A.

    Electromagnetic heating due to higher order modes (HOM) propagation is particularly a concern for continuous wave (CW) particle accelerator machines. Power on the order of several watts could flow out of the cavity's HOM ports in CW operations. The upgrade of the Linac Coherent Light Source (LCLS-II) at SLAC requires a major modification of the design of the higher order mode (HOM) antenna and feed through of the conventional ILC elliptical 9-cell cavity in order to utilize it for LCLS-II. The HOM antenna is required to bear higher RF losses, while relatively maintaining the coupling level of the higher order modes. In this paper, we present a detailed analysis of the heating expected in the HOM coupler with a thorough thermal quench study in comparison with the conventional ILC design. We discuss also how the heat will be removed from the cavity through RF cables with specially designed cooling straps. Finally, we report on the latest experimental results of cavity testing in vertical and horizontal cryostats.

  13. Exponential Lower Bounds and Separation for Query Rewriting

    CERN Document Server

    Kikot, Stanislav; Podolskii, Vladimir; Zakharyaschev, Michael

    2012-01-01

    We establish connections between the size of circuits and formulas computing monotone Boolean functions and the size of first-order and nonrecursive Datalog rewritings for conjunctive queries over OWL 2 QL ontologies. We use known lower bounds and separation results from circuit complexity to prove similar results for the size of rewritings that do not use non-signature constants. For example, we show that, in the worst case, positive existential and nonrecursive Datalog rewritings are exponentially longer than the original queries; nonrecursive Datalog rewritings are in general exponentially more succinct than positive existential rewritings; while first-order rewritings can be superpolynomially more succinct than positive existential rewritings.

  14. Enhanced sensitivity at higher-order exceptional points.

    Science.gov (United States)

    Hodaei, Hossein; Hassan, Absar U; Wittek, Steffen; Garcia-Gracia, Hipolito; El-Ganainy, Ramy; Christodoulides, Demetrios N; Khajavikhan, Mercedeh

    2017-08-09

    Non-Hermitian degeneracies, also known as exceptional points, have recently emerged as a new way to engineer the response of open physical systems, that is, those that interact with the environment. They correspond to points in parameter space at which the eigenvalues of the underlying system and the corresponding eigenvectors simultaneously coalesce. In optics, the abrupt nature of the phase transitions that are encountered around exceptional points has been shown to lead to many intriguing phenomena, such as loss-induced transparency, unidirectional invisibility, band merging, topological chirality and laser mode selectivity. Recently, it has been shown that the bifurcation properties of second-order non-Hermitian degeneracies can provide a means of enhancing the sensitivity (frequency shifts) of resonant optical structures to external perturbations. Of particular interest is the use of even higher-order exceptional points (greater than second order), which in principle could further amplify the effect of perturbations, leading to even greater sensitivity. Although a growing number of theoretical studies have been devoted to such higher-order degeneracies, their experimental demonstration in the optical domain has so far remained elusive. Here we report the observation of higher-order exceptional points in a coupled cavity arrangement-specifically, a ternary, parity-time-symmetric photonic laser molecule-with a carefully tailored gain-loss distribution. We study the system in the spectral domain and find that the frequency response associated with this system follows a cube-root dependence on induced perturbations in the refractive index. Our work paves the way for utilizing non-Hermitian degeneracies in fields including photonics, optomechanics, microwaves and atomic physics.

  15. A Higher Order Godunov Method for Radiation Hydrodynamics: Radiation Subsystem

    CERN Document Server

    Sekora, Michael

    2009-01-01

    A higher order Godunov method for the radiation subsystem of radiation hydrodynamics is presented. A key ingredient of the method is the direct coupling of stiff source term effects to the hyperbolic structure of the system of conservation laws; it is composed of a predictor step that is based on Duhamel's principle and a corrector step that is based on Picard iteration. The method is second order accurate in both time and space, unsplit, asymptotically preserving, and uniformly well behaved from the photon free streaming (hyperbolic) limit through the weak equilibrium diffusion (parabolic) limit and to the strong equilibrium diffusion (hyperbolic) limit. Numerical tests demonstrate second order convergence across various parameter regimes.

  16. Stability and convergence of a higher order rational difference Equation

    CERN Document Server

    Gazor, Hamid

    2011-01-01

    In this paper the asymptotic stability of equilibria and periodic points of the following higher order rational difference Equation x_{n+1} =(alpha x_{n-k})/(1+x_{n}...x_{n-k}), k>=1, n=0,1,... is studied where the parameters ?alpha, betta, and gamma are positive real numbers, and the initial conditions x_{-k}, ..., x_{0} are given arbitrary real numbers. The forbidden set of this equation is found and then, the order reduction method is used to facilitate the analysis of its asymptotic dynamics

  17. Higher order temporal finite element methods through mixed formalisms.

    Science.gov (United States)

    Kim, Jinkyu

    2014-01-01

    The extended framework of Hamilton's principle and the mixed convolved action principle provide new rigorous weak variational formalism for a broad range of initial boundary value problems in mathematical physics and mechanics. In this paper, their potential when adopting temporally higher order approximations is investigated. The classical single-degree-of-freedom dynamical systems are primarily considered to validate and to investigate the performance of the numerical algorithms developed from both formulations. For the undamped system, all the algorithms are symplectic and unconditionally stable with respect to the time step. For the damped system, they are shown to be accurate with good convergence characteristics.

  18. Radiation by solitons due to higher-order dispersion

    DEFF Research Database (Denmark)

    Karpman, V.I.

    1993-01-01

    We consider the Korteweg-de Vries (KdV) and nonlinear Schrodinger (NS) equations with higher-order derivative terms describing dispersive corrections. Conditions of existence of stationary and radiating solitons of the fifth-order KdV equation are obtained. An asymptotic time-dependent solution...... to the latter equation, describing the soliton radiation, is found. The radiation train may be in front as well as behind the soliton, depending on the sign of dispersion. The change rate of the soliton due to the radiation is calculated. A modification of the WKB method, that permits one to describe...

  19. Higher-order photon correlations in pulsed photonic crystal nanolasers

    CERN Document Server

    Elvira, David; Verma, V; Braive, Remy; Beaudoin, Gregoire; Robert-Philip, Isabelle; Sagnes, Isabelle; Baek, Burm; Nam, Sae Woo; Dauler, Eric A; Abram, Izo; Stevens, Martin J; Beveratos, Alexios

    2011-01-01

    We report on the higher-order photon correlations of a high-$\\beta$ nanolaser under pulsed excitation at room temperature. Using a multiplexed four-element superconducting single photon detector we measured g$^{(n)}(\\vec{0})$ with $n$=2,3,4. All orders of correlation display partially chaotic statistics, even at four times the threshold excitation power. We show that this departure from coherence and Poisson statistics is due to the quantum fluctuations associated with the small number of dipoles and photons involved in the lasing process.

  20. A higher-order duration calculus and its completeness

    Institute of Scientific and Technical Information of China (English)

    詹乃军

    2000-01-01

    This paper studies how to describe the real-time behaviour of programs using duration calculus. Since program variables are interpreted as functions over time in real-time programming, and it is inevitable to introduce quantifications over program variables in order to describe local variable declaration and declare local channel and so on. Therefore to establish a higher-order duration calculus (HDC) is necessary. We first establish HDC, then show some real-time properties of programs in terms of HDC, and then, prove that HDC is complete on abstract domains under the assumption that all program variables vary finitely.

  1. Higher-Order Separation Logic in Isabelle/HOLCF

    DEFF Research Database (Denmark)

    Varming, Carsten; Birkedal, Lars

    2008-01-01

    language. This follows the definitional approach common in HOL theorem provers, i.e., the soundness of our model only relies on the soundness of Isabelle/HOL [6]. We use our formalization to give a formally verified proof of Cheney's copying garbage collector [4] using a tagged representation of objects....... The proof generalizes the results in [2]. The proof uses an encoding of the separation logic formula this(h) to capture the heap from before the garbage collection and thus shows another novel use of higher-order separation logic....

  2. Femtosecond filamentation in air and higher-order nonlinearities

    CERN Document Server

    Kolesik, M; Moloney, J V

    2010-01-01

    According to a recent experiment, the instantaneous electronic Kerr effect in air exhibits a strong intensity dependence, the nonlinear refractive index switching sign and crossing over from a self-focusing to a de-focusing nonlinearity. A subsequent theoretical work has demonstrated that this has paradigm-changing consequences for the understanding of filamentation in air, so it is important to subject the idea of higher-order nonlinearities to stringent tests. Here we use numerical modeling to propose an experiment capable of discriminating between the standard and the new intensity-dependent Kerr-effect models.

  3. Contingentism about Individuals and Higher-Order Necessitism

    Directory of Open Access Journals (Sweden)

    Manuel Pérez Otero

    2013-09-01

    Full Text Available Necessitism about individuals claims that necessarily every individual necessarily exists. An analogous necessitist thesis attributes necessary existence to properties and relations. Both theses have been defended by Williamson. Furthermore, Williamson specifically argues against the hybrid conjunction of first-order contingentism (the negation of necessitism about individuals and higher-order necessitism; a combination that would bring about additional drawbacks. I work out a defence of the hybrid combination, including some replies to Williamson’s additional objections. Considerations of ontological parsimony and pre-theoretical intuitions favour the hybrid view over necessitism at all orders (which Williamson mainly defends by invoking considerations of simplicity.

  4. Isotropic Stars in Higher-Order Torsion Scalar Theories

    Directory of Open Access Journals (Sweden)

    Gamal G. L. Nashed

    2016-01-01

    Full Text Available Two different nondiagonal tetrad spaces reproducing spherically symmetric spacetime are applied to the field equations of higher-order torsion scalar theories. Assuming the existence of conformal Killing vector, two isotropic solutions are derived. We show that the first solution is not stable while the second one confirms a stable behavior. We also discuss the construction of the stellar model and show that one of our solutions is capable of such construction while the other is not. Finally, we discuss the generalized Tolman-Oppenheimer-Volkoff and show that one of our models has a tendency to equilibrium.

  5. Isotropic stars in higher-order torsion scalar theories

    CERN Document Server

    Nashed, Gamal G L

    2016-01-01

    Two tetrad spaces reproducing spherically symmetric spacetime are applied to the equations of motion of higher-order torsion theories. Assuming the existence of conformal Killing vector, two isotropic solutions are derived. We show that the first solution is not stable while the second one confirms a stable behavior. We also discuss the construction of the stellar model and show that one of our solution capable of such construction while the other cannot. Finally, we discuss the generalized Tolman-Oppenheimer-Volkoff and show that one of our models has a tendency to equilibrium.

  6. Higher-order Brunnian structures and possible physical realizations

    DEFF Research Database (Denmark)

    A. Baas, Nils; V. Fedorov, D.; S. Jensen, A.

    2014-01-01

    to the binding of systems in nature. It now appears that recent generalization to higher order Brunnian structures may potentially be realized as laboratory made or naturally occurring systems. With the binding energy as measure, we discuss possibilities of physical realization in nuclei, cold atoms......, and condensed matter systems. Appearance is not excluded. However, both the form and the strengths of the interactions must be rather special. The most promising subfields for present searches would be in cold atoms because of external control of effective interactions, or perhaps in condensed-matter systems...

  7. Squeezing of higher order Hermite-Gauss modes

    DEFF Research Database (Denmark)

    Lassen, Mikael Østergaard

    2008-01-01

    The present paper gives an overview of the experimental generation of squeezing in higher order Hermite-Gaussian modes with an optical parametric ampli¯er (OPA). This work was awarded with The European Optical Society (EOS) price 2007. The purpose of the prize is to encourage a European dimension...... in research in pure and applied optics. The EOS prize is awarded based on the selection criteria of high professionalism, academic and technical quality. Following the EOS Prize rules, the conditions for eligibility are that the work was performed in Europe and that it is published under the auspices...

  8. Higher-order polarization singularitites in tailored vector beams

    Science.gov (United States)

    Otte, E.; Alpmann, C.; Denz, C.

    2016-07-01

    Higher-order polarization singularities embedded in tailored vector beams are introduced and experimentally realized. As holographic modulation allows to define order and location of any vectorial singularity, the surrounding vector field can be dynamically shaped. We demonstrate light fields associated with flowers or spider webs due to regular and even irregular patterns of the orientation of polarization ellipses. Beyond that, not yet investigated hybrid structures are introduced that allow generating networks of flowers and webs in very close vicinity. Our results pave the way to applications of singular optics in spatially extended, optimized optical tweezing and high-resolution imaging.

  9. Higher-order-mode fiber optimized for energetic soliton propagation.

    Science.gov (United States)

    Pedersen, Martin E V; Cheng, Ji; Charan, Kriti; Wang, Ke; Xu, Chris; Grüner-Nielsen, Lars; Jakobsen, Dan

    2012-08-15

    We describe the design optimization of a higher-order-mode (HOM) fiber for energetic soliton propagation at wavelengths below 1300 nm. A new HOM fiber is fabricated according to our design criteria. The HOM fiber is pumped at 1045 nm by an energetic femtosecond fiber laser. The soliton self-frequency shift process shifts the center wavelength of the soliton to 1085 nm. The soliton has a temporal duration of 216 fs and a pulse energy of 6.3 nJ. The demonstrated pulse energy is approximately six times higher than the previous record in a solid core fiber at wavelengths below 1300 nm.

  10. Higher Order Mode Properties of Superconducting Two-Spoke Cavities

    Energy Technology Data Exchange (ETDEWEB)

    Hopper, C. S.; Delayen, J. R.; Olave, R. G.

    2011-07-01

    Multi-Spoke cavities lack the cylindrical symmetry that many other cavity types have, which leads to a more complex Higher Order Mode (HOM) spectrum. In addition, spoke cavities offer a large velocity acceptance which means we must perform a detailed analysis of the particle velocity dependence for each mode's R/Q. We present here a study of the HOM properties of two-spoke cavities designed for high-velocity applications. Frequencies, R/Q and field profiles of HOMs have been calculated and are reported.

  11. Higher-order chaotic oscillator using active bessel filter

    DEFF Research Database (Denmark)

    Lindberg, Erik; Mykolaitis, Gytis; Bumelien, Skaidra;

    2010-01-01

    A higher-order oscillator, including a nonlinear unit and an 8th-order low-pass active Bessel filter is described. The Bessel unit plays the role of "three-in-one": a delay line, an amplifier and a filter. Results of hardware experiments and numerical simulation are presented. Depending on the pa...... on the parameters of the nonlinear unit the oscillator operates either in a one-scroll or two-scroll mode. Two positive Lyapunov exponents, found at larger values of the negative slopes of the nonlinear function, characterize the oscillations as hyperchaotic....

  12. Chaotic Time Series Forecasting Using Higher Order Neural Networks

    Directory of Open Access Journals (Sweden)

    Waddah Waheeb

    2016-10-01

    Full Text Available This study presents a novel application and comparison of higher order neural networks (HONNs to forecast benchmark chaotic time series. Two models of HONNs were implemented, namely functional link neural network (FLNN and pi-sigma neural network (PSNN. These models were tested on two benchmark time series; the monthly smoothed sunspot numbers and the Mackey-Glass time-delay differential equation time series. The forecasting performance of the HONNs is compared against the performance of different models previously used in the literature such as fuzzy and neural networks models. Simulation results showed that FLNN and PSNN offer good performance compared to many previously used hybrid models.

  13. Modeling Human Behaviour with Higher Order Logic: Insider Threats

    DEFF Research Database (Denmark)

    Boender, Jaap; Ivanova, Marieta Georgieva; Kammuller, Florian

    2014-01-01

    In this paper, we approach the problem of modeling the human component in technical systems with a view on the difference between the use of model and theory in sociology and computer science. One aim of this essay is to show that building of theories and models for sociology can be compared...... it to the sociological process of logical explanation. As a case study on modeling human behaviour, we present the modeling and analysis of insider threats as a Higher Order Logic theory in Isabelle/HOL. We show how each of the three step process of sociological explanation can be seen in our modeling of insider’s state...

  14. Rewriting the language of creativity

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre

    2013-01-01

    For the past 5 decades the psychology of creativity has been influenced by what is known as the 4 P's of creative expression: person, process, product, and press. This conceptual schema, initially proposed by Rhodes (1961), helped researchers structure their thinking about the phenomenon. However......, it also supported an individualistic, static, and oftentimes disjointed vision of creativity. The present article aims to rewrite this fundamental language of the discipline by using terms that explicitly endorse a systemic, contextual, and dynamic approach. The 5 A's framework—actor, action, artifact......, audience, affordances—is grounded in current literature from sociocultural and ecological psychology as well as theories of the distributed mind and tries to achieve a more comprehensive and unitary perspective on creativity. Several theoretical, methodological, and practical implications are considered....

  15. Higher-Order Spectrum in Understanding Nonlinearity in EEG Rhythms

    Directory of Open Access Journals (Sweden)

    Cauchy Pradhan

    2012-01-01

    Full Text Available The fundamental nature of the brain's electrical activities recorded as electroencephalogram (EEG remains unknown. Linear stochastic models and spectral estimates are the most common methods for the analysis of EEG because of their robustness, simplicity of interpretation, and apparent association with rhythmic behavioral patterns in nature. In this paper, we extend the use of higher-order spectrum in order to indicate the hidden characteristics of EEG signals that simply do not arise from random processes. The higher-order spectrum is an extension Fourier spectrum that uses higher moments for spectral estimates. This essentially nullifies all Gaussian random effects, therefore, can reveal non-Gaussian and nonlinear characteristics in the complex patterns of EEG time series. The paper demonstrates the distinguishing features of bispectral analysis for chaotic systems, filtered noises, and normal background EEG activity. The bispectrum analysis detects nonlinear interactions; however, it does not quantify the coupling strength. The squared bicoherence in the nonredundant region has been estimated to demonstrate nonlinear coupling. The bicoherence values are minimal for white Gaussian noises (WGNs and filtered noises. Higher bicoherence values in chaotic time series and normal background EEG activities are indicative of nonlinear coupling in these systems. The paper shows utility of bispectral methods as an analytical tool in understanding neural process underlying human EEG patterns.

  16. Time-Discrete Higher-Order ALE Formulations: Stability

    KAUST Repository

    Bonito, Andrea

    2013-01-01

    Arbitrary Lagrangian Eulerian (ALE) formulations deal with PDEs on deformable domains upon extending the domain velocity from the boundary into the bulk with the purpose of keeping mesh regularity. This arbitrary extension has no effect on the stability of the PDE but may influence that of a discrete scheme. We examine this critical issue for higher-order time stepping without space discretization. We propose time-discrete discontinuous Galerkin (dG) numerical schemes of any order for a time-dependent advection-diffusion-model problem in moving domains, and study their stability properties. The analysis hinges on the validity of the Reynold\\'s identity for dG. Exploiting the variational structure and assuming exact integration, we prove that our conservative and nonconservative dG schemes are equivalent and unconditionally stable. The same results remain true for piecewise polynomial ALE maps of any degree and suitable quadrature that guarantees the validity of the Reynold\\'s identity. This approach generalizes the so-called geometric conservation law to higher-order methods. We also prove that simpler Runge-Kutta-Radau methods of any order are conditionally stable, that is, subject to a mild ALE constraint on the time steps. Numerical experiments corroborate and complement our theoretical results. © 2013 Society for Industrial and Applied Mathematics.

  17. Higher-Order Cyclostationarity Detection for Spectrum Sensing

    Directory of Open Access Journals (Sweden)

    Julien Renard

    2010-01-01

    Full Text Available Recent years have shown a growing interest in the concept of Cognitive Radios (CRs, able to access portions of the electromagnetic spectrum in an opportunistic operating way. Such systems require efficient detectors able to work in low Signal-to-Noise Ratio (SNR environments, with little or no information about the signals they are trying to detect. Energy detectors are widely used to perform such blind detection tasks, but quickly reach the so-called SNR wall below which detection becomes impossible Tandra (2005. Cyclostationarity detectors are an interesting alternative to energy detectors, as they exploit hidden periodicities present in man-made signals, but absent in noise. Such detectors use quadratic transformations of the signals to extract the hidden sine-waves. While most of the literature focuses on the second-order transformations of the signals, we investigate the potential of higher-order transformations of the signals. Using the theory of Higher-Order Cyclostationarity (HOCS, we derive a fourth-order detector that performs similarly to the second-order ones to detect linearly modulated signals, at SNR around 0 dB, which may be used if the signals of interest do not exhibit second-order cyclostationarity. More generally this paper reviews the relevant aspects of the cyclostationary and HOCS theory, and shows their potential for spectrum sensing.

  18. Laser-PlasmaWakefield Acceleration with Higher Order Laser Modes

    Energy Technology Data Exchange (ETDEWEB)

    Geddes, C.G.R.; Cormier-Michel, E.; Esarey, E.; Schroeder, C.B.; Mullowney, P.; Paul, K.; Cary, J.R.; Leemans, W.P.

    2010-06-01

    Laser-plasma collider designs point to staging of multiple accelerator stages at the 10 GeV level, which are to be developed on the upcoming BELLA laser, while Thomson Gamma source designs use GeV stages, both requiring efficiency and low emittance. Design and scaling of stages operating in the quasi-linear regime to address these needs are presented using simulations in the VORPAL framework. In addition to allowing symmetric acceleration of electrons and positrons, which is important for colliders, this regime has the property that the plasma wakefield is proportional to the transverse gradient of the laser intensity profile. We demonstrate use of higher order laser modes to tailor the laser pulse and hence the transverse focusing forces in the plasma. In particular, we show that by using higher order laser modes, we can reduce the focusing fields and hence increase the matched electron beam radius, which is important to increased charge and efficiency, while keeping the low bunch emittance required for applications.

  19. Visualizing Higher Order Finite Elements: FY05 Yearly Report.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, David; Pebay, Philippe Pierre

    2005-11-01

    This report contains an algorithm for decomposing higher-order finite elementsinto regions appropriate for isosurfacing and proves the conditions under which thealgorithm will terminate. Finite elements are used to create piecewise polynomialapproximants to the solution of partial differential equations for which no analyticalsolution exists. These polynomials represent fields such as pressure, stress, and mo-mentim. In the past, these polynomials have been linear in each parametric coordinate.Each polynomial coefficient must be uniquely determined by a simulation, and thesecoefficients are called degrees of freedom. When there are not enough degrees of free-dom, simulations will typically fail to produce a valid approximation to the solution.Recent work has shown that increasing the number of degrees of freedom by increas-ing the order of the polynomial approximation (instead of increasing the number offinite elements, each of which has its own set of coefficients) can allow some typesof simulations to produce a valid approximation with many fewer degrees of freedomthan increasing the number of finite elements alone. However, once the simulation hasdetermined the values of all the coefficients in a higher-order approximant, tools donot exist for visual inspection of the solution.This report focuses on a technique for the visual inspection of higher-order finiteelement simulation results based on decomposing each finite element into simplicialregions where existing visualization algorithms such as isosurfacing will work. Therequirements of the isosurfacing algorithm are enumerated and related to the placeswhere the partial derivatives of the polynomial become zero. The original isosurfacingalgorithm is then applied to each of these regions in turn.3 AcknowledgementThe authors would like to thank David Day and Louis Romero for their insight into poly-nomial system solvers and the LDRD Senior Council for the opportunity to pursue thisresearch. The authors were

  20. Ontological Queries: Rewriting and Optimization (Extended Version)

    CERN Document Server

    Gottlob, Georg; Pieris, Andreas

    2011-01-01

    Ontological queries are evaluated against an ontology rather than directly on a database. The evaluation and optimization of such queries is an intriguing new problem for database research. In this paper we discuss two important aspects of this problem: query rewriting and query optimization. Query rewriting consists of the compilation of an ontological query into an equivalent query against the underlying relational database. The focus here is on soundness and completeness. We review previous results and present a new rewriting algorithm for rather general types of ontological constraints. In particular, we show how a conjunctive query against an ontology can be compiled into a union of conjunctive queries against the underlying database. Ontological query optimization, in this context, attempts to improve this process so to produce possibly small and cost-effective UCQ rewritings for an input query. We review existing optimization methods, and propose an effective new method that works for linear Datalog+/-...

  1. Chemical Freeze-Out and Higher Order Multiplicity Moments

    CERN Document Server

    Tawfik, A

    2013-01-01

    We calculate the non-normalized moments of the particle multiplicity within the framework of the hadron resonance gas (HRG) model. At finite chemical potential $\\mu$, a non-monotonic behavior is observed in the thermal evolution of third order moment (skewness $S$) and the higher order ones as well. Among others, this observation likely reflects dynamical fluctuations and strong correlations. The signatures of non-monotonicity in the normalized fourth order moment (kurtosis $\\kappa$) and its products get very clear. Based on these findings, we introduce a novel condition characterizing the universal freeze-out curve. The chemical freeze-out parameters $T$ and $\\mu$ are described by vanishing $\\kappa\\, \\sigma^2$ or equivalently $m_4=3\\,\\chi^2$, where $\\sigma$, $\\chi$ and $m_4$ are the standard deviation, susceptibility and fourth order moment, respectively. The fact that the HRG model is not able to release information about criticality related to the confinement and chiral dynamics should not veil the observa...

  2. A higher-order theory of emotional consciousness.

    Science.gov (United States)

    LeDoux, Joseph E; Brown, Richard

    2017-03-07

    Emotional states of consciousness, or what are typically called emotional feelings, are traditionally viewed as being innately programmed in subcortical areas of the brain, and are often treated as different from cognitive states of consciousness, such as those related to the perception of external stimuli. We argue that conscious experiences, regardless of their content, arise from one system in the brain. In this view, what differs in emotional and nonemotional states are the kinds of inputs that are processed by a general cortical network of cognition, a network essential for conscious experiences. Although subcortical circuits are not directly responsible for conscious feelings, they provide nonconscious inputs that coalesce with other kinds of neural signals in the cognitive assembly of conscious emotional experiences. In building the case for this proposal, we defend a modified version of what is known as the higher-order theory of consciousness.

  3. Higher Order Variability Properties of Accreting Black Holes

    CERN Document Server

    Maccarone, T J; Maccarone, Thomas J.; Coppi, Paolo S.

    2002-01-01

    To better constrain the emission mechanism underlying the hard state of galactic black hole candidates, we use high-time resolution RXTE lightcurves for Cyg X-1 and GX 399-4 to compute two higher order variability statistics for these objects, the skewness and the Fourier bispectrum. Similar analyses, in particular using the skewness measure, have been attempted before, but the photon collection area of RXTE allows us to present results of much greater statistical significance. The results for the two objects are qualitatively similar, reinforcing the idea that the same basic mechanisms are at work in both. We find a significantly positive skewness for variability timescales less than $\\sim 1 $ second, and a {\\it negative} skewness for timescale $1- 5 $ sec. Such a skewness pattern cannot be reproduced by the simplest shot variability models where individual shots have a fixed profile and intensity and are uncorrelated in time. Further evidence against simple shot models comes from the significant detection o...

  4. SU(2) Higher-order effective quark interactions from polarization

    Science.gov (United States)

    Braghin, Fábio L.

    2016-10-01

    Higher order quark effective interactions are found for SU(2) flavor by departing from a non-local quark-quark interaction. By integrating out a component of the quark field, the determinant is expanded in chirally symmetric and symmetry breaking effective interactions up to the fifth order in the quark bilinears. The resulting coupling constants are resolved in the leading order of the longwavelength limit and exact numerical ratios between several of these coupling constants are obtained in the large quark mass limit. In this level, chiral invariant interactions only show up in even powers of the quark bilinears, i.e. O(ψ bar ψ) 2 n (n = 1 , 2 , 3 , . .), whereas (explicit) chiral symmetry breaking terms emerge as O(ψ bar ψ) n being always proportional to some power of the Lagrangian quark mass.

  5. Higher-order nonlinear effects in a Josephson parametric amplifier

    Science.gov (United States)

    Kochetov, Bogdan A.; Fedorov, Arkady

    2015-12-01

    Nonlinearity of the current-phase relationship of a Josephson junction is the key resource for a Josephson parametric amplifier (JPA) as well as for a Josephson traveling-wave parametric amplifier, the only devices in which the quantum limit for added noise has so far been approached at microwave frequencies. A standard approach to describe JPA takes into account only the lowest order (cubic) nonlinearity resulting in a Duffing-like oscillator equation of motion or in a Kerr-type nonlinearity term in the Hamiltonian. In this paper we derive the quantum expression for the gain of JPA including all orders of the Josephson junction nonlinearity in the linear response regime. We then analyze gain saturation effect for stronger signals within a semiclassical approach. Our results reveal nonlinear effects of higher orders and their implications for operation of a JPA.

  6. Podolsky`s higher-order electromagnetism from first principles

    Energy Technology Data Exchange (ETDEWEB)

    Accioly, A. [Sao Paulo, Univ. Estadual Paulista (Brazil). Instituto de Fisica Teorica; Mukai, H. [Maringa, Fundacao Universidade Estadual de Maringa (Brazil). Dept. de Fisica

    1997-07-01

    Podolsky`s higher-order field equations are obtained by generalizing the laws of Podolsky`s electrostatics, which follow from Coulomb`s generalized law and superposition, to be consistent with special relativity. In addition, it is necessary to take into account the independence of the observed charge of a particle on tis speed. It is also shown that the gauge-independent term concerning the Feynman propagator for Podolsky`s generalized electrodynamics has a good ultraviolet behaviour at the expense of a negative metric massive ghost which, contrary to what is currently assumed in the literature, is non-tachyonic. A brief discussion on Podolsky`s characteristic length is presented as well.

  7. Polymer quantization, stability and higher-order time derivative terms

    CERN Document Server

    Cumsille, Patricio; Ossandon, Sebastian; Reyes, Camilo

    2015-01-01

    The stability of higher-order time derivative theories using the polymer extension of quantum mechanics is studied. First, we focus on the well-known Pais-Uhlenbeck model and by casting the theory into the sum of two decoupled harmonic oscillators we show that the energy spectrum is composed with positive and negative energy parts. The Schrodinger quantization of the model with creation and annihilations operators leads to a theory with unbounded Hamiltonian that can be interpreted in terms of normal particles and Lee-Wick-like particles responsible for the instability. We investigate whether the fundamental discreetness implicit in the polymer quantization can regularize the effects of the negative energies introduced by the Lee-Wick-like particles which are associated to a high-energy scale. Precisely, we show that the polymer quantization leads to a positive defined Hamiltonian whose stability is improved as the number of Lee-Wick-like particles grows.

  8. A higher-order theory of emotional consciousness

    Science.gov (United States)

    LeDoux, Joseph E.; Brown, Richard

    2017-01-01

    Emotional states of consciousness, or what are typically called emotional feelings, are traditionally viewed as being innately programmed in subcortical areas of the brain, and are often treated as different from cognitive states of consciousness, such as those related to the perception of external stimuli. We argue that conscious experiences, regardless of their content, arise from one system in the brain. In this view, what differs in emotional and nonemotional states are the kinds of inputs that are processed by a general cortical network of cognition, a network essential for conscious experiences. Although subcortical circuits are not directly responsible for conscious feelings, they provide nonconscious inputs that coalesce with other kinds of neural signals in the cognitive assembly of conscious emotional experiences. In building the case for this proposal, we defend a modified version of what is known as the higher-order theory of consciousness. PMID:28202735

  9. Recognition of higher order patterns in proteins: immunologic kernels.

    Directory of Open Access Journals (Sweden)

    Robert D Bremel

    Full Text Available By applying analysis of the principal components of amino acid physical properties we predicted cathepsin cleavage sites, MHC binding affinity, and probability of B-cell epitope binding of peptides in tetanus toxin and in ten diverse additional proteins. Cross-correlation of these metrics, for peptides of all possible amino acid index positions, each evaluated in the context of a ±25 amino acid flanking region, indicated that there is a strongly repetitive pattern of short peptides of approximately thirty amino acids each bounded by cathepsin cleavage sites and each comprising B-cell linear epitopes, MHC-I and MHC-II binding peptides. Such "immunologic kernel" peptides comprise all signals necessary for adaptive immunologic cognition, response and recall. The patterns described indicate a higher order spatial integration that forms a symbolic logic coordinating the adaptive immune system.

  10. Higher-order techniques for some problems of nonlinear control

    Directory of Open Access Journals (Sweden)

    Sarychev Andrey V.

    2002-01-01

    Full Text Available A natural first step when dealing with a nonlinear problem is an application of some version of linearization principle. This includes the well known linearization principles for controllability, observability and stability and also first-order optimality conditions such as Lagrange multipliers rule or Pontryagin's maximum principle. In many interesting and important problems of nonlinear control the linearization principle fails to provide a solution. In the present paper we provide some examples of how higher-order methods of differential geometric control theory can be used for the study nonlinear control systems in such cases. The presentation includes: nonlinear systems with impulsive and distribution-like inputs; second-order optimality conditions for bang–bang extremals of optimal control problems; methods of high-order averaging for studying stability and stabilization of time-variant control systems.

  11. Neutron scattering studies on chromatin higher-order structure

    Energy Technology Data Exchange (ETDEWEB)

    Graziano, V.; Gerchman, S.E.; Schneider, D.K.; Ramakrishnan, V. [Brookhaven National Laboratory, Upton, NY (United States)

    1994-12-31

    We have been engaged in studies of the structure and condensation of chromatin into the 30nm filament using small-angle neutron scattering. We have also used deuterated histone H1 to determine its location in the chromatin 30nm filament. Our studies indicate that chromatin condenses with increasing ionic strength to a limiting structure that has a mass per unit length of 6-7 nucleosomes/11 nm. They also show that the linker histone H1/H5 is located in the interior of the chromatin filament, in a position compatible with its binding to the inner face of the nucleosome. Analysis of the mass per unit length as a function of H5 stoichiometry suggests that 5-7 contiguous nucleosomes need to have H5 bound before a stable higher order structure can exist.

  12. Higher order mode propagation in nonuniform circular ducts

    Science.gov (United States)

    Cho, Y. C.; Ingard, K. U.

    1980-01-01

    This paper presents an analytical investigation of higher order mode propagation in a nonuniform circular duct without mean flow. An approximate wave equation is derived on the assumptions that the duct cross section varies slowly and that mode conversion is negligible. Exact closed form solutions are obtained for a particular class of converging-diverging circular duct which is here referred to as 'circular cosh duct'. Numerical results are presentd in terms of the transmission loss for the various duct shapes and frequencies. The results are applicable to studies of multimodal propagation as well as single mode propagation. The results are also applicable to studies of sound radiation from certain types of contoured inlet ducts, or of sound propagation in a converging-diverging duct of somewhat different shape from a cosh duct.

  13. Higher order branching of periodic orbits from polynomial isochrones

    Directory of Open Access Journals (Sweden)

    B. Toni

    1999-09-01

    Full Text Available We discuss the higher order local bifurcations of limit cycles from polynomial isochrones (linearizable centers when the linearizing transformation is explicitly known and yields a polynomial perturbation one-form. Using a method based on the relative cohomology decomposition of polynomial one-forms complemented with a step reduction process, we give an explicit formula for the overall upper bound of branch points of limit cycles in an arbitrary $n$ degree polynomial perturbation of the linear isochrone, and provide an algorithmic procedure to compute the upper bound at successive orders. We derive a complete analysis of the nonlinear cubic Hamiltonian isochrone and show that at most nine branch points of limit cycles can bifurcate in a cubic polynomial perturbation. Moreover, perturbations with exactly two, three, four, six, and nine local families of limit cycles may be constructed.

  14. Higher order statistical moment application for solar PV potential analysis

    Science.gov (United States)

    Basri, Mohd Juhari Mat; Abdullah, Samizee; Azrulhisham, Engku Ahmad; Harun, Khairulezuan

    2016-10-01

    Solar photovoltaic energy could be as alternative energy to fossil fuel, which is depleting and posing a global warming problem. However, this renewable energy is so variable and intermittent to be relied on. Therefore the knowledge of energy potential is very important for any site to build this solar photovoltaic power generation system. Here, the application of higher order statistical moment model is being analyzed using data collected from 5MW grid-connected photovoltaic system. Due to the dynamic changes of skewness and kurtosis of AC power and solar irradiance distributions of the solar farm, Pearson system where the probability distribution is calculated by matching their theoretical moments with that of the empirical moments of a distribution could be suitable for this purpose. On the advantage of the Pearson system in MATLAB, a software programming has been developed to help in data processing for distribution fitting and potential analysis for future projection of amount of AC power and solar irradiance availability.

  15. Higher order numerical differentiation on the Infinity Computer

    CERN Document Server

    Sergeyev, Yaroslav D

    2012-01-01

    There exist many applications where it is necessary to approximate numerically derivatives of a function which is given by a computer procedure. In particular, all the fields of optimization have a special interest in such a kind of information. In this paper, a new way to do this is presented for a new kind of a computer -- the Infinity Computer -- able to work numerically with finite, infinite, and infinitesimal numbers. It is proved that the Infinity Computer is able to calculate values of derivatives of a higher order for a wide class of functions represented by computer procedures. It is shown that the ability to compute derivatives of arbitrary order automatically and accurate to working precision is an intrinsic property of the Infinity Computer related to its way of functioning. Numerical examples illustrating the new concepts and numerical tools are given.

  16. Higher Order Reentrant Post Modes in Cylindrical Cavities

    CERN Document Server

    McAllister, Ben T; Parker, Stephen R; Tobar, Michael E

    2016-01-01

    Reentrant cavities are microwave resonant devices employed in a number of different areas of physics. They are appealing due to their simple frequency tuning mechanism, which offers large tuning ranges. Reentrant cavities are, in essence, 3D lumped LC circuits consisting of a conducting central post embedded in a resonant cavity. The lowest order reentrant mode (which transforms from the TM010 mode) has been extensively studied in past publications. In this work we show the existence of higher order reentrant post modes (which transform from the TM01n mode family). We characterize these new modes in terms of their frequency tuning, filling factors and quality factors, as well as discuss some possible applications of these modes in fundamental physics tests.

  17. Mixed Higher Order Variational Model for Image Recovery

    Directory of Open Access Journals (Sweden)

    Pengfei Liu

    2014-01-01

    Full Text Available A novel mixed higher order regularizer involving the first and second degree image derivatives is proposed in this paper. Using spectral decomposition, we reformulate the new regularizer as a weighted L1-L2 mixed norm of image derivatives. Due to the equivalent formulation of the proposed regularizer, an efficient fast projected gradient algorithm combined with monotone fast iterative shrinkage thresholding, called, FPG-MFISTA, is designed to solve the resulting variational image recovery problems under majorization-minimization framework. Finally, we demonstrate the effectiveness of the proposed regularization scheme by the experimental comparisons with total variation (TV scheme, nonlocal TV scheme, and current second degree methods. Specifically, the proposed approach achieves better results than related state-of-the-art methods in terms of peak signal to ratio (PSNR and restoration quality.

  18. Evidence for several higher order structural elements in ribosomal RNA.

    Science.gov (United States)

    Woese, C R; Gutell, R R

    1989-05-01

    Comparative analysis of small subunit ribosomal RNA sequences suggests the existence of two new higher order interactions: (i) a double-helical structure involving positions 505-507 and 524-526 (Escherichia coli numbering) and (ii) an interaction between the region of position 130 and the helix located approximately between positions 180 and 195. In the first of these, one of the strands of the helix exists in the bulge loop, and the other strand exists in the terminal loop of a previously recognized compound helix involving positions 500-545. Therefore, the new structure formally represents a pseudoknot. In the second, the insertion/deletion of a nucleotide in the vicinity of position 130 correlates with the length of the helix in the 180-195 region, the latter having a 3-base-pair stalk when the base in question is deleted and a stalk of approximately 10 pairs when it is inserted.

  19. Inflationary scenarios in Starobinsky model with higher order corrections

    Energy Technology Data Exchange (ETDEWEB)

    Artymowski, Michał [Institute of Physics, Jagiellonian University,Łojasiewicza 11, 30-348 Kraków (Poland); Lalak, Zygmunt [Institute of Theoretical Physics, Faculty of Physics, University of Warsaw,ul. Pasteura 5, 02-093 Warsaw (Poland); Lewicki, Marek [Institute of Theoretical Physics, Faculty of Physics, University of Warsaw,ul. Pasteura 5, 02-093 Warsaw (Poland); Michigan Center for Theoretical Physics, University of Michigan,450 Church Street, Ann Arbor MI 48109 (United States)

    2015-06-17

    We consider the Starobinsky inflation with a set of higher order corrections parametrised by two real coefficients λ{sub 1} ,λ{sub 2}. In the Einstein frame we have found a potential with the Starobinsky plateau, steep slope and possibly with an additional minimum, local maximum or a saddle point. We have identified three types of inflationary behaviour that may be generated in this model: i) inflation on the plateau, ii) at the local maximum (topological inflation), iii) at the saddle point. We have found limits on parameters λ{sub i} and initial conditions at the Planck scale which enable successful inflation and disable eternal inflation at the plateau. We have checked that the local minimum away from the GR vacuum is stable and that the field cannot leave it neither via quantum tunnelling nor via thermal corrections.

  20. Research on Life Signals Detection Based on Higher Order Statistics

    Directory of Open Access Journals (Sweden)

    Jian-Jun Li

    2012-10-01

    Full Text Available The life signals are built on harmonic mode for their low frequency, quasi-periodicity, low SNR, and the easy submerged in strong clutter noise. The method for detecting life signal based on adaptive filter and high order statistics is presented, in which neither the Gaussian supposition of the observed signal, nor a prior information about the waveform and arrival time of the observed signal is necessary. The principle of method is to  separate the spectrum of input signal into many narrow frequency bands, whose Sub-band signal  is followed by a short-time estimation of higher-order statistics so as to suppress Gaussian noises. Simulated results show that the method can effectively detect life signals from noise with good convergence speed and stability, and greatly improve the signal quality with respect to LMS method.

  1. Dependable software through higher-order strategic programming.

    Energy Technology Data Exchange (ETDEWEB)

    Winter, Victor Lono (University of Nebraska at Omaha); Fraij, Fares (University of Texas at El Paso); Roach, Steve (University of Texas at El Paso)

    2004-03-01

    Program transformation is a restricted form of software construction that can be amenable to formal verification. When successful, the nature of the evidence provided by such a verification is considered strong and can constitute a major component of an argument that a high-consequence or safety-critical system meets its dependability requirements. This article explores the application of novel higher-order strategic programming techniques to the development of a portion of a class loader for a restricted implementation of the Java Virtual Machine (JVM). The implementation is called the SSP and is intended for use in high-consequence safety-critical embedded systems. Verification of the strategic program using ACL2 is also discussed.

  2. Higher order mode analysis of the SPL cavities

    CERN Document Server

    Schuh, M; Tuckmantel, J; Welsch, CP

    2010-01-01

    Higher Order Modes (HOMs) can severely limit the operation of superconducting cavities in a linac with high beam current, high duty factor and complex pulse structure. The full HOM spectrum has to be analyzed in order to identify potentially dangerous modes already during the design phase and to define their damping requirements. For this purpose a dedicated beam simulation code focused on beam-HOMinteraction was developed, taking into account important effects like the HOMfrequency spread, beam input jitter, different chopping patterns, as well as klystron and alignment errors. Here, the code is used to investigate in detail the HOM properties of the cavities foreseen in the Superconducting Proton Linac (SPL) at CERN and their potential to drive beam instabilities. Special attention is given to HOM excitation by chopped pulses with high repetition rate.

  3. Higher-order structure and epidemic dynamics in clustered networks

    CERN Document Server

    Ritchie, Martin; House, Thomas; Kiss, Istvan Z

    2013-01-01

    Clustering is typically measured by the ratio of triangles to all triples, open or closed. Generating clustered networks, and how clustering affects dynamics on networks, is reasonably well understood for certain classes of networks \\cite{vmclust, karrerclust2010}, e.g., networks composed of lines and non-overlapping triangles. In this paper we show that it is possible to generate networks which, despite having the same degree distribution and equal clustering, exhibit different higher-order structure, specifically, overlapping triangles and other order-four (a closed network motif composed of four nodes) structures. To distinguish and quantify these additional structural features, we develop a new network metric capable of measuring order-four structure which, when used alongside traditional network metrics, allows us to more accurately describe a network's topology. Three network generation algorithms are considered: a modified configuration model and two rewiring algorithms. By generating homogeneous netwo...

  4. Higher-order phase transitions on financial markets

    Science.gov (United States)

    Kasprzak, A.; Kutner, R.; Perelló, J.; Masoliver, J.

    2010-08-01

    Statistical and thermodynamic properties of the anomalous multifractal structure of random interevent (or intertransaction) times were thoroughly studied by using the extended continuous-time random walk (CTRW) formalism of Montroll, Weiss, Scher, and Lax. Although this formalism is quite general (and can be applied to any interhuman communication with nontrivial priority), we consider it in the context of a financial market where heterogeneous agent activities can occur within a wide spectrum of time scales. As the main general consequence, we found (by additionally using the Saddle-Point Approximation) the scaling or power-dependent form of the partition function, Z(q'). It diverges for any negative scaling powers q' (which justifies the name anomalous) while for positive ones it shows the scaling with the general exponent τ(q'). This exponent is the nonanalytic (singular) or noninteger power of q', which is one of the pilar of higher-order phase transitions. In definition of the partition function we used the pausing-time distribution (PTD) as the central one, which takes the form of convolution (or superstatistics used, e.g. for describing turbulence as well as the financial market). Its integral kernel is given by the stretched exponential distribution (often used in disordered systems). This kernel extends both the exponential distribution assumed in the original version of the CTRW formalism (for description of the transient photocurrent measured in amorphous glassy material) as well as the Gaussian one sometimes used in this context (e.g. for diffusion of hydrogen in amorphous metals or for aging effects in glasses). Our most important finding is the third- and higher-order phase transitions, which can be roughly interpreted as transitions between the phase where high frequency trading is most visible and the phase defined by low frequency trading. The specific order of the phase transition directly depends upon the shape exponent α defining the stretched

  5. Technical Decision Making With Higher Order Structure Data: Perspectives on Higher Order Structure Characterization From the Biopharmaceutical Industry.

    Science.gov (United States)

    Weiss, William F; Gabrielson, John P; Al-Azzam, Wasfi; Chen, Guodong; Davis, Darryl L; Das, Tapan K; Hayes, David B; Houde, Damian; Singh, Satish K

    2016-12-01

    Characterization of the higher order structure (HOS) of protein-based biopharmaceutical products is an important aspect of their development. Opinions vary about how best to apply biophysical methods, in which contexts to use these methods, and how to use the resulting data to make technical decisions as drug candidates are commercialized [Gabrielson JP, Weiss WF IV. J Pharm Sci. 2015;104(4):1240-1245]. The aim of this commentary is to provide guidance for the development and implementation of a robust and comprehensive HOS characterization strategy. We first consider important concepts involved in developing a strategy that is appropriately suited to a particular biologic, and then discuss ways industry can partner with academia, technology companies, government laboratories, and regulatory agencies to improve the consistency with which HOS characterization is applied across the biopharmaceutical industry. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  6. Chemical freeze-out and higher order multiplicity moments

    Energy Technology Data Exchange (ETDEWEB)

    Tawfik, A., E-mail: a.tawfik@eng.mti.edu.eg

    2014-02-15

    We calculate the non-normalized moments of the particle multiplicity within the framework of the hadron resonance gas (HRG) model. At finite chemical potential μ, a non-monotonic behavior is observed in the thermal evolution of third order moment (skewness S) and the higher order ones as well. The signatures of non-monotonicity in the normalized fourth order moment (kurtosis κ) and its products get very clear. Among others, this observation likely reflects dynamical fluctuations and strong correlations. Based on these findings, we introduce the physics of the universal freeze-out curve. It is found that the chemical freeze-out parameters T and μ are described by vanishing κσ{sup 2} or equivalently m{sub 4}=3χ{sup 2}, where σ, χ and m{sub 4} are the standard deviation, susceptibility and fourth order moment, respectively. The fact that the HRG model is not able to release information about criticality related to the confinement and chiral dynamics should not veil the observations related to the chemical freeze-out. Recent lattice QCD studies strongly advocate the main conclusion of the present paper.

  7. Higher order SVD analysis for dynamic texture synthesis.

    Science.gov (United States)

    Costantini, Roberto; Sbaiz, Luciano; Süsstrunk, Sabine

    2008-01-01

    Videos representing flames, water, smoke, etc., are often defined as dynamic textures: "textures" because they are characterized by the redundant repetition of a pattern and "dynamic" because this repetition is also in time and not only in space. Dynamic textures have been modeled as linear dynamic systems by unfolding the video frames into column vectors and describing their trajectory as time evolves. After the projection of the vectors onto a lower dimensional space by a singular value decomposition (SVD), the trajectory is modeled using system identification techniques. Synthesis is obtained by driving the system with random noise. In this paper, we show that the standard SVD can be replaced by a higher order SVD (HOSVD), originally known as Tucker decomposition. HOSVD decomposes the dynamic texture as a multidimensional signal (tensor) without unfolding the video frames on column vectors. This is a more natural and flexible decomposition, since it permits us to perform dimension reduction in the spatial, temporal, and chromatic domain, while standard SVD allows for temporal reduction only. We show that for a comparable synthesis quality, the HOSVD approach requires, on average, five times less parameters than the standard SVD approach. The analysis part is more expensive, but the synthesis has the same cost as existing algorithms. Our technique is, thus, well suited to dynamic texture synthesis on devices limited by memory and computational power, such as PDAs or mobile phones.

  8. Analytical Higher-Order Model for Flexible and Stretchable Sensors

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yongfang; ZHU Hongbin; LIU Cheng; LIU Xu; LIU Fuxi; L Yanjun

    2015-01-01

    The stretchable sensor wrapped around a foldable airfoil or embedded inside of it has great potential for use in the monitoring of the structural status of the foldable airfoil. The design methodology is important to the development of the stretchable sensor for status monitoring on the foldable airfoil. According to the requirement of mechanical flexibility of the sensor, the combined use of a layered flexible structural formation and a strain isolation layer is implemented. An analytical higher-order model is proposed to predict the stresses of the strain-isolation layer based on the shear-lag model for the safe design of the flexible and stretchable sensors. The normal stress and shear stress equations in the constructed structure of the sensors are obtained by the proposed model. The stress distribution in the structure is investigated when bending load is applied to the structures. The numerical results show that the proposed model can predict the variation of normal stress and shear stress along the thickness of the strain-isolation (polydimethylsiloxane) layer accurately. The results by the proposed model are in good agreement with the finite element method, in which the normal stress is variable while the shear stress is invariable along the thickness direction of strain-isolation layer. The high-order model is proposed to predict the stresses of the layered structure of the flexible and stretchable sensor for monitoring the status of the foldable airfoil.

  9. Higher Order Aberration and Astigmatism in Children with Hyperopic Amblyopia.

    Science.gov (United States)

    Choi, Seung Kwon; Chang, Ji Woong

    2016-02-01

    To investigate the changes in corneal higher-order aberration (HOA) during amblyopia treatment and the correlation between HOA and astigmatism in hyperopic amblyopia children. In this retrospective study, a total of 72 eyes from 72 patients ranging in age from 38 to 161 months were included. Patients were divided into two groups based on the degree of astigmatism. Corneal HOA was measured using a KR-1W aberrometer at the initial visit and at 3-, 6-, and 12-month follow-ups. Correlation analysis was performed to assess the association between HOA and astigmatism. A total of 72 patients were enrolled in this study, 37 of which were classified as belonging to the higher astigmatism group, while 35 were assigned to the lower astigmatism group. There was a statistically significant difference in success rate between the higher and lower astigmatism groups. In both groups, all corneal HOAs were significantly reduced during amblyopia treatment. When comparing the two groups, a significant difference in coma HOA at the 12-month follow-up was detected (p = 0.043). In the Pearson correlation test, coma HOA at the 12-month follow-up demonstrated a statistically significant correlation with astigmatism and a stronger correlation with astigmatism in the higher astigmatism group than in the lower astigmatism group (coefficient values, 0.383 and 0.284 as well as p = 0.021 and p = 0.038, respectively). HOA, particularly coma HOA, correlated with astigmatism and could exert effects in cases involving hyperopic amblyopia.

  10. Analysis of higher order harmonics with holographic reflection gratings

    Science.gov (United States)

    Mas-Abellan, P.; Madrigal, R.; Fimia, A.

    2017-05-01

    Silver halide emulsions have been considered one of the most energetic sensitive materials for holographic applications. Nonlinear recording effects on holographic reflection gratings recorded on silver halide emulsions have been studied by different authors obtaining excellent experimental results. In this communication specifically we focused our investigation on the effects of refractive index modulation, trying to get high levels of overmodulation that will produce high order harmonics. We studied the influence of the overmodulation and its effects on the transmission spectra for a wide exposure range by use of 9 μm thickness films of ultrafine grain emulsion BB640, exposed to single collimated beams using a red He-Ne laser (wavelength 632.8 nm) with Denisyuk configuration obtaining a spatial frequency of 4990 l/mm recorded on the emulsion. The experimental results show that high overmodulation levels of refractive index produce second order harmonics with high diffraction efficiency (higher than 75%) and a narrow grating bandwidth (12.5 nm). Results also show that overmodulation produce diffraction spectra deformation of the second order harmonic, transforming the spectrum from sinusoidal to approximation of square shape due to very high overmodulation. Increasing the levels of overmodulation of refractive index, we have obtained higher order harmonics, obtaining third order harmonic with diffraction efficiency (up to 23%) and narrowing grating bandwidth (5 nm). This study is the first step to develop a new easy technique to obtain narrow spectral filters based on the use of high index modulation reflection gratings.

  11. A Simplified Algorithm for Inverting Higher Order Diffusion Tensors

    Directory of Open Access Journals (Sweden)

    Laura Astola

    2014-11-01

    Full Text Available In Riemannian geometry, a distance function is determined by an inner product on the tangent space. In Riemann–Finsler geometry, this distance function can be determined by a norm. This gives more freedom on the form of the so-called indicatrix or the set of unit vectors. This has some interesting applications, e.g., in medical image analysis, especially in diffusion weighted imaging (DWI. An important application of DWI is in the inference of the local architecture of the tissue, typically consisting of thin elongated structures, such as axons or muscle fibers, by measuring the constrained diffusion of water within the tissue. From high angular resolution diffusion imaging (HARDI data, one can estimate the diffusion orientation distribution function (dODF, which indicates the relative diffusivity in all directions and can be represented by a spherical polynomial. We express this dODF as an equivalent spherical monomial (higher order tensor to directly generalize the (second order diffusion tensor approach. To enable efficient computation of Riemann–Finslerian quantities on diffusion weighted (DW-images, such as the metric/norm tensor, we present a simple and efficient algorithm to invert even order spherical monomials, which extends the familiar inversion of diffusion tensors, i.e., symmetric matrices.

  12. Higher Order Modes Excitation of Micro Cantilever Beams

    KAUST Repository

    Jaber, Nizar

    2014-05-01

    In this study, we present analytical and experimental investigation of electrically actuated micro cantilever based resonators. These devices are fabricated using polyimide and coated with chrome and gold layers from both sides. The cantilevers are highly curled up due to stress gradient, which is a common imperfection in surface micro machining. Using a laser Doppler vibrometer, we applied a noise signal to experimentally find the first four resonance frequencies. Then, using a data acquisition card, we swept the excitation frequency around the first four natural modes of vibrations. Theoretically, we derived a reduced order model using the Galerkin method to simulate the dynamics of the system. Extensive numerical analysis and computations were performed. The numerical analysis was able to provide good matching with experimental values of the resonance frequencies. Also, we proved the ability to excite higher order modes using partial electrodes with shapes that resemble the shape of the mode of interest. Such micro-resonators are shown to be promising for applications in mass and gas sensing.

  13. Higher order acoustoelastic Lamb wave propagation in stressed plates.

    Science.gov (United States)

    Pei, Ning; Bond, Leonard J

    2016-11-01

    Modeling and experiments are used to investigate Lamb wave propagation in the direction perpendicular to an applied stress. Sensitivity, in terms of changes in velocity, for both symmetrical and anti-symmetrical modes was determined. Codes were developed based on analytical expressions for waves in loaded plates and they were used to give wave dispersion curves. The experimental system used a pair of compression wave transducers on variable angle wedges, with set separation, and variable frequency tone burst excitation, on an aluminum plate 0.16 cm thick with uniaxial applied loads. The loads, which were up to 600 με, were measured using strain gages. Model results and experimental data are in good agreement. It was found that the change in Lamb wave velocity, due to the acoustoelastic effect, for the S1 mode exhibits about ten times more sensitive, in terms of velocity change, than the traditional bulk wave measurements, and those performed using the fundamental Lamb modes. The data presented demonstrate the potential for the use of higher order Lamb modes for online industrial stress measurement in plate, and that the higher sensitivity seen offers potential for improved measurement systems.

  14. A Recurrence Relation Approach to Higher Order Quantum Superintegrability

    Directory of Open Access Journals (Sweden)

    Ernie G. Kalnins

    2011-03-01

    Full Text Available We develop our method to prove quantum superintegrability of an integrable 2D system, based on recurrence relations obeyed by the eigenfunctions of the system with respect to separable coordinates. We show that the method provides rigorous proofs of superintegrability and explicit constructions of higher order generators for the symmetry algebra. We apply the method to 5 families of systems, each depending on a parameter k, including most notably the caged anisotropic oscillator, the Tremblay, Turbiner and Winternitz system and a deformed Kepler-Coulomb system, and we give proofs of quantum superintegrability for all rational values of k, new for 4 of these systems. In addition, we show that the explicit information supplied by the special function recurrence relations allows us to prove, for the first time in 4 cases, that the symmetry algebra generated by our lowest order symmetries closes and to determine the associated structure equations of the algebras for each k. We have no proof that our generating symmetries are of lowest possible order, but we have no counterexamples, and we are confident we can can always find any missing generators from our raising and lowering operator recurrences. We also get for free, one variable models of the action of the symmetry algebra in terms of difference operators. We describe how the Stäckel transform acts and show that it preserves the structure equations.

  15. Higher-order web link analysis using multilinear algebra.

    Energy Technology Data Exchange (ETDEWEB)

    Kenny, Joseph P.; Bader, Brett William (Sandia National Laboratories, Albuquerque, NM); Kolda, Tamara Gibson

    2005-07-01

    Linear algebra is a powerful and proven tool in web search. Techniques, such as the PageRank algorithm of Brin and Page and the HITS algorithm of Kleinberg, score web pages based on the principal eigenvector (or singular vector) of a particular non-negative matrix that captures the hyperlink structure of the web graph. We propose and test a new methodology that uses multilinear algebra to elicit more information from a higher-order representation of the hyperlink graph. We start by labeling the edges in our graph with the anchor text of the hyperlinks so that the associated linear algebra representation is a sparse, three-way tensor. The first two dimensions of the tensor represent the web pages while the third dimension adds the anchor text. We then use the rank-1 factors of a multilinear PARAFAC tensor decomposition, which are akin to singular vectors of the SVD, to automatically identify topics in the collection along with the associated authoritative web pages.

  16. Certifiable higher order sliding mode control: Practical stability margins approach

    Science.gov (United States)

    Panathula, Chandrasekhara Bharath

    The Higher Order Sliding Mode (HOSM) controllers are well known for their robustness/insensitivity to bounded perturbations and for handling any given arbitrary relative degree system. The HOSM controller is to be certified for robustness to unmodeled dynamics, before deploying the controller for practical applications. Phase Margin (PM) and Gain Margin ( GM) are the classical characteristics used in linear systems to quantify the linear controller robustness to unmodeled dynamics, and certain values of these margins are required to certify the controller. These conventional margins (PM and GM) are extended to Practical Stability Phase Margin (PSPM) and Practical Stability Gain Margin (PSGM) in this dissertation, and are used to quantify the HOSM control robustness to unmodeled dynamics, presiding the tool to close the gap for HOSM control certification. The proposed robustness metrics ( PSPM and PSGM) are identified by developing tools/algorithms based on Describing Function-Harmonic Balance method. In order for the HOSM controller to achieve the prescribed values on robustness metrics ( PSPM and PSGM), the HOSM controller is cascaded with a linear compensator. A case study of the application of the proposed metrics (PSPM and PSGM) for the certification of F-16 aircraft HOSM attitude control robustness to cascade unmodeled dynamics is presented. In addition, several simulation examples are presented to verify and to validate the proposed methodology.

  17. Higher-order graph wavelets and sparsity on circulant graphs

    Science.gov (United States)

    Kotzagiannidis, Madeleine S.; Dragotti, Pier Luigi

    2015-08-01

    The notion of a graph wavelet gives rise to more advanced processing of data on graphs due to its ability to operate in a localized manner, across newly arising data-dependency structures, with respect to the graph signal and underlying graph structure, thereby taking into consideration the inherent geometry of the data. In this work, we tackle the problem of creating graph wavelet filterbanks on circulant graphs for a sparse representation of certain classes of graph signals. The underlying graph can hereby be data-driven as well as fixed, for applications including image processing and social network theory, whereby clusters can be modelled as circulant graphs, respectively. We present a set of novel graph wavelet filter-bank constructions, which annihilate higher-order polynomial graph signals (up to a border effect) defined on the vertices of undirected, circulant graphs, and are localised in the vertex domain. We give preliminary results on their performance for non-linear graph signal approximation and denoising. Furthermore, we provide extensions to our previously developed segmentation-inspired graph wavelet framework for non-linear image approximation, by incorporating notions of smoothness and vanishing moments, which further improve performance compared to traditional methods.

  18. The Weak Field Limit of Higher Order Gravity

    CERN Document Server

    Stabile, Arturo

    2008-01-01

    The Higher Order Theories of Gravity - $f(R, R_{\\alpha\\beta}R^{\\alpha\\beta})$ - theory, where $R$ is the Ricci scalar, $R_{\\alpha\\beta}$ is the Ricci tensor and $f$ is any analytic function - have recently attracted a lot of interest as alternative candidates to explain the observed cosmic acceleration, the flatness of the rotation curves of spiral galaxies and other relevant astrophysical phenomena. It is a crucial point testing these alternative theories in the so called weak field and newtonian limit of a $f(R, R_{\\alpha\\beta}R^{\\alpha\\beta})$ - theory. With this "perturbation technique" it is possible to find spherically symmetric solutions and compare them with the ones of General Relativity. On both approaches we found a modification of General Relativity: the behaviour of gravitational potential presents a modification Yukawa - like in the newtonian case and a massive propagation in the weak field case. When the modification of the theory is removed (i.e. $f(R, R_{\\alpha\\beta}R^{\\alpha\\beta}) = R$, Hil...

  19. Effective description of higher-order scalar-tensor theories

    Science.gov (United States)

    Langlois, David; Mancarella, Michele; Noui, Karim; Vernizzi, Filippo

    2017-05-01

    Most existing theories of dark energy and/or modified gravity, involving a scalar degree of freedom, can be conveniently described within the framework of the Effective Theory of Dark Energy, based on the unitary gauge where the scalar field is uniform. We extend this effective approach by allowing the Lagrangian in unitary gauge to depend on the time derivative of the lapse function. Although this dependence generically signals the presence of an extra scalar degree of freedom, theories that contain only one propagating scalar degree of freedom, in addition to the usual tensor modes, can be constructed by requiring the initial Lagrangian to be degenerate. Starting from a general quadratic action, we derive the dispersion relations for the linear perturbations around Minkowski and a cosmological background. Our analysis directly applies to the recently introduced Degenerate Higher-Order Scalar-Tensor (DHOST) theories. For these theories, we find that one cannot recover a Poisson-like equation in the static linear regime except for the subclass that includes the Horndeski and so-called "beyond Horndeski" theories. We also discuss Lorentz-breaking models inspired by Horava gravity.

  20. Predicting perceptual learning from higher-order cortical processing.

    Science.gov (United States)

    Wang, Fang; Huang, Jing; Lv, Yaping; Ma, Xiaoli; Yang, Bin; Wang, Encong; Du, Boqi; Li, Wu; Song, Yan

    2016-01-01

    Visual perceptual learning has been shown to be highly specific to the retinotopic location and attributes of the trained stimulus. Recent psychophysical studies suggest that these specificities, which have been associated with early retinotopic visual cortex, may in fact not be inherent in perceptual learning and could be related to higher-order brain functions. Here we provide direct electrophysiological evidence in support of this proposition. In a series of event-related potential (ERP) experiments, we recorded high-density electroencephalography (EEG) from human adults over the course of learning in a texture discrimination task (TDT). The results consistently showed that the earliest C1 component (68-84ms), known to reflect V1 activity driven by feedforward inputs, was not modulated by learning regardless of whether the behavioral improvement is location specific or not. In contrast, two later posterior ERP components (posterior P1 and P160-350) over the occipital cortex and one anterior ERP component (anterior P160-350) over the prefrontal cortex were progressively modified day by day. Moreover, the change of the anterior component was closely correlated with improved behavioral performance on a daily basis. Consistent with recent psychophysical and imaging observations, our results indicate that perceptual learning can mainly involve changes in higher-level visual cortex as well as in the neural networks responsible for cognitive functions such as attention and decision making.

  1. Higher order statistical frequency domain decomposition for operational modal analysis

    Science.gov (United States)

    Nita, G. M.; Mahgoub, M. A.; Sharyatpanahi, S. G.; Cretu, N. C.; El-Fouly, T. M.

    2017-02-01

    Experimental methods based on modal analysis under ambient vibrational excitation are often employed to detect structural damages of mechanical systems. Many of such frequency domain methods, such as Basic Frequency Domain (BFD), Frequency Domain Decomposition (FFD), or Enhanced Frequency Domain Decomposition (EFFD), use as first step a Fast Fourier Transform (FFT) estimate of the power spectral density (PSD) associated with the response of the system. In this study it is shown that higher order statistical estimators such as Spectral Kurtosis (SK) and Sample to Model Ratio (SMR) may be successfully employed not only to more reliably discriminate the response of the system against the ambient noise fluctuations, but also to better identify and separate contributions from closely spaced individual modes. It is shown that a SMR-based Maximum Likelihood curve fitting algorithm may improve the accuracy of the spectral shape and location of the individual modes and, when combined with the SK analysis, it provides efficient means to categorize such individual spectral components according to their temporal dynamics as coherent or incoherent system responses to unknown ambient excitations.

  2. Degree of musical expertise modulates higher order brain functioning.

    Science.gov (United States)

    Oechslin, Mathias S; Van De Ville, Dimitri; Lazeyras, François; Hauert, Claude-Alain; James, Clara E

    2013-09-01

    Using functional magnetic resonance imaging, we show for the first time that levels of musical expertise stepwise modulate higher order brain functioning. This suggests that degree of training intensity drives such cerebral plasticity. Participants (non-musicians, amateurs, and expert musicians) listened to a comprehensive set of specifically composed string quartets with hierarchically manipulated endings. In particular, we implemented 2 irregularities at musical closure that differed in salience but were both within the tonality of the piece (in-key). Behavioral sensitivity scores (d') of both transgressions perfectly separated participants according to their level of musical expertise. By contrasting brain responses to harmonic transgressions against regular endings, functional brain imaging data showed compelling evidence for stepwise modulation of brain responses by both violation strength and expertise level in a fronto-temporal network hosting universal functions of working memory and attention. Additional independent testing evidenced an advantage in visual working memory for the professionals, which could be predicted by musical training intensity. The here introduced findings of brain plasticity demonstrate the progressive impact of musical training on cognitive brain functions that may manifest well beyond the field of music processing.

  3. A general higher-order remap algorithm for ALE calculations

    Energy Technology Data Exchange (ETDEWEB)

    Chiravalle, Vincent P [Los Alamos National Laboratory

    2011-01-05

    A numerical technique for solving the equations of fluid dynamics with arbitrary mesh motion is presented. The three phases of the Arbitrary Lagrangian Eulerian (ALE) methodology are outlined: the Lagrangian phase, grid relaxation phase and remap phase. The Lagrangian phase follows a well known approach from the HEMP code; in addition the strain rate andflow divergence are calculated in a consistent manner according to Margolin. A donor cell method from the SALE code forms the basis of the remap step, but unlike SALE a higher order correction based on monotone gradients is also added to the remap. Four test problems were explored to evaluate the fidelity of these numerical techniques, as implemented in a simple test code, written in the C programming language, called Cercion. Novel cell-centered data structures are used in Cercion to reduce the complexity of the programming and maximize the efficiency of memory usage. The locations of the shock and contact discontinuity in the Riemann shock tube problem are well captured. Cercion demonstrates a high degree of symmetry when calculating the Sedov blast wave solution, with a peak density at the shock front that is similar to the value determined by the RAGE code. For a flyer plate test problem both Cercion and FLAG give virtually the same velocity temporal profile at the target-vacuum interface. When calculating a cylindrical implosion of a steel shell, Cercion and FLAG agree well and the Cercion results are insensitive to the use of ALE.

  4. Non-rigid registration using higher-order mutual information

    Science.gov (United States)

    Rueckert, D.; Clarkson, M. J.; Hill, D. L. G.; Hawkes, D. J.

    2000-03-01

    Non-rigid registration of multi-modality images is an important tool for assessing temporal and structural changesbetween images. For rigid registration, voxel similarity measures like mutual information have been shown to alignimages from different modalities accurately and robustly. For non-rigid registration, mutual information can besensitive to local variations of intensity which in MR images may be caused by RF inhomogeneity. The reasonfor the sensitivity of mutual information towards intensity variations stems from the fact that mutual informationignores any spatial information. In this paper we propose an extension of the mutual information framework whichincorporates spatial information about higher-order image structure into the registration process and has the potentialto improve the accuracy and robustness of non-rigid registration in the presence of intensity variations. We haveapplied the non-rigid registration algorithm to a number of simulated MR brain images of a digital phantom whichhave been degraded by a simulated intensity shading and a known deformation. In addition, we have applied thealgorithm for the non-rigid registration of eight pre- and post-operative brain MR images which were acquired withan interventional MR scanner and therefore have substantial intensity shading due to RF field inhomogeneities. Inall cases the second-order estimate of mutual information leads to robust and accurate registration.

  5. Near integrability of kink lattice with higher order interactions

    CERN Document Server

    Jiang, Yunguo; He, Song

    2016-01-01

    In the paper, we make use of Manton's analytical method to investigate the force between kink and the anti-kink with large distance in $1+1$ dimensional field theory. The related potential has infinite order corrections of exponential pattern, and coefficients for each order are determined. These coefficients can also be obtained by solving the equation of the fluctuation around the vacuum. At the lowest order, the kink lattice represents the Toda lattice. With higher order correction terms, the kink lattice can represent one kind of the generic Toda lattice. With only two sites, the kink lattice is classically integrable. If the number of sites of the lattice is larger than two, the kink lattice is not integrable but a near integrable system. We take use of the Flaschka's variables to study the Lax pair of the kink lattice. These Flaschka's variables have interesting algebraic relations and the non-integrability can be manifested. We also discussed the higher Hamiltonians for the deformed open Toda lattice, ...

  6. Emotion recognition from EEG using higher order crossings.

    Science.gov (United States)

    Petrantonakis, Panagiotis C; Hadjileontiadis, Leontios J

    2010-03-01

    Electroencephalogram (EEG)-based emotion recognition is a relatively new field in the affective computing area with challenging issues regarding the induction of the emotional states and the extraction of the features in order to achieve optimum classification performance. In this paper, a novel emotion evocation and EEG-based feature extraction technique is presented. In particular, the mirror neuron system concept was adapted to efficiently foster emotion induction by the process of imitation. In addition, higher order crossings (HOC) analysis was employed for the feature extraction scheme and a robust classification method, namely HOC-emotion classifier (HOC-EC), was implemented testing four different classifiers [quadratic discriminant analysis (QDA), k-nearest neighbor, Mahalanobis distance, and support vector machines (SVMs)], in order to accomplish efficient emotion recognition. Through a series of facial expression image projection, EEG data have been collected by 16 healthy subjects using only 3 EEG channels, namely Fp1, Fp2, and a bipolar channel of F3 and F4 positions according to 10-20 system. Two scenarios were examined using EEG data from a single-channel and from combined-channels, respectively. Compared with other feature extraction methods, HOC-EC appears to outperform them, achieving a 62.3% (using QDA) and 83.33% (using SVM) classification accuracy for the single-channel and combined-channel cases, respectively, differentiating among the six basic emotions, i.e., happiness, surprise, anger, fear, disgust, and sadness. As the emotion class-set reduces its dimension, the HOC-EC converges toward maximum classification rate (100% for five or less emotions), justifying the efficiency of the proposed approach. This could facilitate the integration of HOC-EC in human machine interfaces, such as pervasive healthcare systems, enhancing their affective character and providing information about the user's emotional status (e.g., identifying user's emotion

  7. Threshold resummation and higher order effects in QCD

    Energy Technology Data Exchange (ETDEWEB)

    Ringer, Felix Maximilian

    2015-06-26

    Quantum chromodynamics (QCD) is a quantum field theory that describes the strong interactions between quarks and gluons, the building blocks of all hadrons. Thanks to the experimental progress over the past decades, there has been an ever-growing need for QCD precision calculations for scattering processes involving hadrons. For processes at large momentum transfer, perturbative QCD offers a systematic approach for obtaining precise predictions. This approach relies on two key concepts: the asymptotic freedom of QCD and factorization. In a perturbative calculation at higher orders, the infrared cancellation between virtual and real emission diagrams generally leaves behind logarithmic contributions. In many observables relevant for hadronic scattering these logarithms are associated with a kinematic threshold and are hence known as ''threshold logarithms''. They become large when the available phase space for real gluon emission shrinks. In order to obtain a reliable prediction from QCD, the threshold logarithms need to be taken into account to all orders in the strong coupling constant, a procedure known as ''threshold resummation''. The main focus of my PhD thesis is on studies of QCD threshold resummation effects beyond the next-to-leading logarithmic order. Here we primarily consider the production of hadron pairs in hadronic collisions as an example. In addition, we also consider hadronic jet production, which is particularly interesting for the phenomenology at the LHC. For both processes, we fully take into account the non-trivial QCD color structure of the underlying partonic hard- scattering cross sections. We find that threshold resummation leads to sizable numerical effects in the kinematic regimes relevant for comparisons to experimental data.

  8. Higher order variability properties of accreting black holes

    Science.gov (United States)

    Maccarone, Thomas J.; Coppi, Paolo S.

    2002-11-01

    To better constrain the emission mechanism underlying the hard state of galactic black hole candidates, we use high-time resolution RXTE light curves for Cyg X-1 and GX 339-4 to compute two higher order variability statistics for these objects, the skewness and the Fourier bispectrum. Similar analyses, in particular using the skewness measure, have been attempted previously, but the photon collection area of RXTE allows us to present results of much greater statistical significance. The results for the two objects are qualitatively similar, reinforcing the idea that the same basic mechanisms are at work in both. We find a significantly positive skewness for variability time-scales less than ~1 s, and a negative skewness for time-scales from 1 to 5 s. Such a skewness pattern cannot be reproduced by the simplest shot variability models where individual shots have a fixed profile and intensity and are uncorrelated in time. Further evidence against simple-shot models comes from the significant detection of a non-zero bicoherence for Fourier periods ~0.1-10 s, implying that significant coupling does exist between variations on these time-scales. We discuss how current popular models for variability in black hole systems can be modified to match these observations. Using simulated light curves, we suggest that the most likely way to reproduce this observed behaviour is to have the variability come in groups of many shots, with the number of shots per unit time fitting an envelope function that has a rapid rise and a slow decay, while the individual shots have a slow rise and a rapid decay. Invoking a finite-energy reservoir that is depleted by each shot is a natural way of producing the required shot correlations.

  9. 1957-2007: 50 Years of Higher Order Programming Languages

    Directory of Open Access Journals (Sweden)

    Alen Lovrenčić

    2009-06-01

    Full Text Available Fifty years ago one of the greatest breakthroughs in computer programming and in the history of computers happened -- the appearance of FORTRAN, the first higher-order programming language. From that time until now hundreds of programming languages were invented, different programming paradigms were defined, all with the main goal to make computer programming easier and closer to as many people as possible. Many battles were fought among scientists as well as among developers around concepts of programming, programming languages and paradigms. It can be said that programming paradigms and programming languages were very often a trigger for many changes and improvements in computer science as well as in computer industry. Definitely, computer programming is one of the cornerstones of computer science.Today there are many tools that give a help in the process of programming, but there is still a programming tasks that can be solved only manually. Therefore, programming is still one of the most creative parts of interaction with computers.Programmers should chose programming language in accordance to task they have to solve, but very often, they chose it in accordance to their personal preferences, their beliefs and many other subjective reasons.Nevertheless, the market of programming languages can be merciless to languages as history was merciless to some people, even whole nations. Programming languages and developers get born, live and die leaving more or less tracks and successors, and not always the best survives. The history of programming languages is closely connected to the history of computers and computer science itself. Every single thing from one of them has its reflexions onto the other. This paper gives a short overview of last fifty years of computer programming and computer programming languages, but also gives many ideas that influenced other aspects of computer science. Particularly, programming paradigms are described, their

  10. Initial Semantics for higher-order typed syntax in Coq

    Directory of Open Access Journals (Sweden)

    Benedikt Ahrens

    2011-01-01

    Full Text Available Initial Semantics aims at characterizing the syntax associated to a signature as the initial object of some category. We present an initial semantics result for typed higher-order syntax together with its formalization in the Coq proof assistant. The main theorem was first proved on paper in the second author’s PhD thesis in 2010, and verified formally shortly afterwards.To a simply–typed binding signature S over a fixed set T of object types we associate a category called the category of representations of S. We show that this category has an initial object Sigma(S, i.e. an object Sigma(S from which there is precisely one morphism i_R : Sigma(S -> R to any object R of this category. From its construction it will be clear that the object Sigma(S merits the name abstract syntax associated to S: it is given by an inductive set – parametrized by a set of free variables and dependent on object types – the type of whose constructors are each given by the arities of the signature S.Our theorem is implemented and proved correct in the proof assistant Coq through heavy use of dependent types. The approach through monads gives rise to an implementation of syntax where both terms and variables are intrinsically typed, i.e. where the object types are rejected in the meta–level types. Terms are implemented as a Coq data type – which play the role of sets – dependent on an object type as well as on a type family of free variables.This article is to be seen as a research article rather than about the formalization of a classical mathematical result. The nature of our theorem – involving lengthy, technical proofs and complicated algebraic structures – makes it particularly interesting for formal verification. Our goal is to promote the use of computer theorem provers as research tools, and, accordingly, a new way of publishing mathematical results: a parallel description of a theorem and its formalization should allow the verification of

  11. Analysis of wheezes using wavelet higher order spectral features.

    Science.gov (United States)

    Taplidou, Styliani A; Hadjileontiadis, Leontios J

    2010-07-01

    . This paves the way for the use of the wavelet higher order spectral features as an input vector to an efficient classifier. Apparently, this would integrate the intrinsic characteristics of wheezes within computerized diagnostic tools toward their more efficient evaluation.

  12. Higher-order spectra for identification of nonlinear modal coupling

    Science.gov (United States)

    Hickey, Daryl; Worden, Keith; Platten, Michael F.; Wright, Jan R.; Cooper, Jonathan E.

    2009-05-01

    Over the past four decades considerable work has been done in the area of power spectrum estimation. The information contained within the power spectrum relates to a signal's autocorrelation or 'second-order statistics'. The power spectrum provides a complete statistical description of a Gaussian process; however, a problem with this information is that it is phase blind. This problem is addressed if one turns to a system's frequency response function (FRF). The FRF graphs the magnitude and phase of the frequency response of a system; in order to do this it requires information regarding the frequency content of the input and output signals. Situations arise in science and engineering whereby signal analysts are required to look beyond second-order statistics and analyse a signal's higher-order statistics (HOS). HOS or spectra give information on a signal's deviation from Gaussianity and consequently are a good indicator function for the presence of nonlinearity within a system. One of the main problems in nonlinear system identification is that of high modal density. Many modelling schemes involve making some expansion of the nonlinear restoring force in terms of polynomial or other basis terms. If more than one degree-of-freedom is involved this becomes a multivariate problem and the number of candidate terms in the expansion grows explosively with the order of nonlinearity and the number of degrees-of-freedom. This paper attempts to use HOS to detect and qualify nonlinear behaviour for a number of symmetrical and asymmetrical systems over a range of degrees-of-freedom. In doing so the paper also attempts to show that HOS are a more sensitive tool than the FRF in detecting nonlinearity. Furthermore, the object of this paper is to try and identify which modes couple in a nonlinear manner in order to reduce the number of candidate coupling terms, for a model, as much as possible. The bispectrum method has previously been applied to simple low-DOF systems with high

  13. Values Education through Aggadic Stories: The Didactic Rewriter as Interpreter

    Science.gov (United States)

    Weinstein, Sara

    2016-01-01

    Didactic rewrites of aggadic stories are an important resource in values education. This study, geared primarily toward teachers involved in choosing curricular materials, investigates how the didactic rewriter actually becomes an interpreter, rather than a mere transmitter, of the original text. The personal values of the rewriters can influence…

  14. Values Education through Aggadic Stories: The Didactic Rewriter as Interpreter

    Science.gov (United States)

    Weinstein, Sara

    2016-01-01

    Didactic rewrites of aggadic stories are an important resource in values education. This study, geared primarily toward teachers involved in choosing curricular materials, investigates how the didactic rewriter actually becomes an interpreter, rather than a mere transmitter, of the original text. The personal values of the rewriters can influence…

  15. Koch Curves: Rewriting System, Geometry and Application

    Directory of Open Access Journals (Sweden)

    Mamta Rani

    2011-01-01

    Full Text Available Problem statement: Recently, new Koch curves have been generated by dividing the initiator into three unequal parts. There is no formal rewriting system to generate such kind of curves. Approach: It is required to measure the new changed geometrical properties. Generalized rewriting systems for the new Koch curves have been developed. Results: New formulas have been given to measure their geometrical properties. Conclusion/Recommendations: The geometrical properties of new Koch curves make them more suitable as antennas in wireless communication than the conventional Koch curve.

  16. Parallel Execution of Multi Set Constraint Rewrite Rules

    DEFF Research Database (Denmark)

    Sulzmann, Martin; Lam, Edmund Soon Lee

    2008-01-01

    that the underlying constraint rewrite implementation executes rewrite steps in parallel on increasingly popular becoming multi-core architectures. We design and implement efficient algorithms which allow for the parallel execution of multi-set constraint rewrite rules. Our experiments show that we obtain some......Multi-set constraint rewriting allows for a highly parallel computational model and has been used in a multitude of application domains such as constraint solving, agent specification etc. Rewriting steps can be applied simultaneously as long as they do not interfere with each other.We wish...

  17. Transfinite reductions in orthogonal term rewriting systems

    NARCIS (Netherlands)

    J.R. Kennaway (Richard); J.W. Klop (Jan Willem); M.R. Sleep (Ronan); F.-J. de Vries (Fer-Jan)

    1991-01-01

    textabstractStrongly convergent reduction is the fundamental notion of reduction in infinitary orthogonal term rewriting systems (OTRSs). For these we prove the Transfinite Parallel Moves Lemma and the Compressing Lemma. Strongness is necessary as shown by counterexamples. Normal forms, which we

  18. Mark formation model for optical rewritable recording

    NARCIS (Netherlands)

    Brusche, J.H.

    2007-01-01

    Optically rewritable discs contain one or more so-called recording stacks. These stacks consist of various grooved layers. At least one of these layers contains a so-called phase-change material. In the recording layer, amorphous regions are formed on a crystalline background by means of high power

  19. On Comparison of Rewriting and skopostheory

    Institute of Scientific and Technical Information of China (English)

    雷鸣

    2015-01-01

    Andrew Lefevere and Hans Vermeer’ are outstanding figures in the history of translation studies.Their theory Rewriting and Skopostheory can be considered as milestone in their study history.This paper makes comparison between two theories with regard to their main features and makes persons-in-the-translation further get a deeper understanding of two theories.

  20. A Rewriting Logic Approach to Type Inference

    Science.gov (United States)

    Ellison, Chucky; Şerbănuţă, Traian Florin; Roşu, Grigore

    Meseguer and Roşu proposed rewriting logic semantics (RLS) as a programing language definitional framework that unifies operational and algebraic denotational semantics. RLS has already been used to define a series of didactic and real languages, but its benefits in connection with defining and reasoning about type systems have not been fully investigated. This paper shows how the same RLS style employed for giving formal definitions of languages can be used to define type systems. The same term-rewriting mechanism used to execute RLS language definitions can now be used to execute type systems, giving type checkers or type inferencers. The proposed approach is exemplified by defining the Hindley-Milner polymorphic type inferencer mathcal{W} as a rewrite logic theory and using this definition to obtain a type inferencer by executing it in a rewriting logic engine. The inferencer obtained this way compares favorably with other definitions or implementations of mathcal{W}. The performance of the executable definition is within an order of magnitude of that of highly optimized implementations of type inferencers, such as that of OCaml.

  1. Mark formation modeling in optical rewritable recording

    NARCIS (Netherlands)

    Brusche, J.H.; Segal, A.; Vuik, C.; Urbach, H.P.

    2006-01-01

    In optical rewritable recording media, such as the Blu-ray Disc, amorphous marks are formed on a crystalline background of a phase-change layer, by means of short, high power laser pulses. In order to improve this data storage concept, it is of great importance to understand the mark formation

  2. Phase structure rewrite systems in information retrieval

    Science.gov (United States)

    Klingbiel, P. H.

    1985-01-01

    Operational level automatic indexing requires an efficient means of normalizing natural language phrases. Subject switching requires an efficient means of translating one set of authorized terms to another. A phrase structure rewrite system called a Lexical Dictionary is explained that performs these functions. Background, operational use, other applications and ongoing research are explained.

  3. Mark formation modeling in optical rewritable recording

    NARCIS (Netherlands)

    Brusche, J.H.; Segal, A.; Vuik, C.; Urbach, H.P.

    2006-01-01

    In optical rewritable recording media, such as the Blu-ray Disc, amorphous marks are formed on a crystalline background of a phase-change layer, by means of short, high power laser pulses. In order to improve this data storage concept, it is of great importance to understand the mark formation proce

  4. Operational semantics of term rewriting with priorities

    NARCIS (Netherlands)

    Pol, J.C. van de

    2008-01-01

    We study the semantics of term rewriting systems with rule priorities (PRS), as introduced in [1]. Three open problems posed in that paper are solved, by giving counter examples. Moreover, a class of executable PRSs is identified. A translation of PRSs into transition system specifications (TSS) is

  5. Termination of canonical context-sensitive rewriting and productivity of rewrite systems

    Directory of Open Access Journals (Sweden)

    Salvador Lucas

    2015-12-01

    Full Text Available Termination of programs, i.e., the absence of infinite computations, ensures the existence of normal forms for all initial expressions, thus providing an essential ingredient for the definition of a normalization semantics for functional programs. In lazy functional languages, though, infinite data structures are often delivered as the outcome of computations. For instance, the list of all prime numbers can be returned as a neverending stream of numerical expressions or data structures. If such streams are allowed, requiring termination is hopeless. In this setting, the notion of productivity can be used to provide an account of computations with infinite data structures, as it "captures the idea of computability, of progress of infinite-list programs" (B.A. Sijtsma, On the Productivity of Recursive List Definitions, ACM Transactions on Programming Languages and Systems 11(4:633-649, 1989. However, in the realm of Term Rewriting Systems, which can be seen as (first-order, untyped, unconditional functional programs, termination of Context-Sensitive Rewriting (CSR has been showed equivalent to productivity of rewrite systems through appropriate transformations. In this way, tools for proving termination of CSR can be used to prove productivity. In term rewriting, CSR is the restriction of rewriting that arises when reductions are allowed on selected arguments of function symbols only. In this paper we show that well-known results about the computational power of CSR are useful to better understand the existing connections between productivity of rewrite systems and termination of CSR, and also to obtain more powerful techniques to prove productivity of rewrite systems.

  6. Compiling CIL Rewriting Language for Multiprocessors

    Institute of Scientific and Technical Information of China (English)

    田新民; 王鼎兴; 等

    1994-01-01

    The high-level Conpiler Intermediate Language CIL is a general-purpose description language of parallel graph rewriting computational model intended for paralled implementation of declarative languages on multiprocessor systems.In this paper,we first outline a new Hybrid Execution Model(HEM) and corresponding parallel abstract machine PAM/TGR based on extended parallel Graph Rewriting Computational Model EGRCM for implementing CIL language on distributed memory multiprocessor systems.Then we focus on the compiling CIL language with various optimizing techniques such as pattern matching,rule indexing,node ordering and compile-time partial scheduling.The experimental results on a 16-node transputer Array demonstrates the effectiveness of our model and strategies.

  7. Lazy AC-Pattern Matching for Rewriting

    OpenAIRE

    Walid Belkhir; Alain Giorgetti

    2012-01-01

    We define a lazy pattern-matching mechanism modulo associativity and commutativity. The solutions of a pattern-matching problem are stored in a lazy list composed of a first substitution at the head and a non-evaluated object that encodes the remaining computations. We integrate the lazy AC-matching in a strategy language: rewriting rule and strategy application produce a lazy list of terms.

  8. Lazy AC-Pattern Matching for Rewriting

    Directory of Open Access Journals (Sweden)

    Walid Belkhir

    2012-04-01

    Full Text Available We define a lazy pattern-matching mechanism modulo associativity and commutativity. The solutions of a pattern-matching problem are stored in a lazy list composed of a first substitution at the head and a non-evaluated object that encodes the remaining computations. We integrate the lazy AC-matching in a strategy language: rewriting rule and strategy application produce a lazy list of terms.

  9. Strongly typed rewriting for coupled software transformation

    OpenAIRE

    Cunha, Alcino; Visser, J

    2006-01-01

    Coupled transformations occur in software evolution when multiple artifacts must be modified in such a way that they remain consistent with each other. An important example involves the coupled transformation of a data type, its instances, and the programs that consume or produce it. Previously, we have provided a formal treatment of transformation of the first two: data types and instances. The treatment involved the construction of type-safe, type-changing strategic rewrite systems. In this...

  10. On the Identities of Symmetry for the -Euler Polynomials of Higher Order

    Directory of Open Access Journals (Sweden)

    Park KyoungHo

    2009-01-01

    Full Text Available The main purpose of this paper is to investigate several further interesting properties of symmetry for the multivariate -adic fermionic integral on . From these symmetries, we can derive some recurrence identities for the -Euler polynomials of higher order, which are closely related to the Frobenius-Euler polynomials of higher order. By using our identities of symmetry for the -Euler polynomials of higher order, we can obtain many identities related to the Frobenius-Euler polynomials of higher order.

  11. Generation of higher order Gauss-Laguerre modes in single-pass 2nd harmonic generation

    DEFF Research Database (Denmark)

    Buchhave, Preben; Tidemand-Lichtenberg, Peter

    2008-01-01

    We present a realistic method for dynamic simulation of the development of higher order modes in second harmonic generation. The deformation of the wave fronts due to the nonlinear interaction is expressed by expansion in higher order Gauss-Laguerre modes.......We present a realistic method for dynamic simulation of the development of higher order modes in second harmonic generation. The deformation of the wave fronts due to the nonlinear interaction is expressed by expansion in higher order Gauss-Laguerre modes....

  12. A Higher Order Analysis of the Factor Structure of the Myers-Briggs Type Indicator.

    Science.gov (United States)

    Johnson, William L.; Mauzey, Edward; Johnson, Annabel M.; Murphy, Stanley D.; Zimmerman, Kurt J.

    2001-01-01

    Examines the higher order structure of Form G of the Myers Briggs Type Indicator. A third order component analysis of a sample (N=926) found two higher order components. This higher order analysis contributes to the research literature pertaining to the generalized structure of the personality measure. (Contains 44 references and 1 table.) (GCP)

  13. On the expressiveness and decidability of higher-order process calculi

    NARCIS (Netherlands)

    Lanese, Ivan; Perez, Jorge A.; Sangiorgi, Davide; Schmitt, Alan

    2011-01-01

    In higher-order process calculi, the values exchanged in communications may contain processes. A core calculus of higher-order concurrency is studied; it has only the operators necessary to express higher-order communications: input prefix, process output, and parallel composition. By exhibiting a d

  14. Higher order hierarchical discretization scheme for surface integral equations for layered media

    DEFF Research Database (Denmark)

    Jørgensen, Erik; Kim, Oleksiy S.; Meincke, Peter;

    2004-01-01

    equation. This higher order MoM solution comprises higher order curved patches for the geometry modeling and higher order hierarchical basis functions for expansion of the electric surface current density. Due to the hierarchical property of the basis functions, the order of the expansion can be selected...

  15. A Higher Order Analysis of the Factor Structure of the Myers-Briggs Type Indicator.

    Science.gov (United States)

    Johnson, William L.; Mauzey, Edward; Johnson, Annabel M.; Murphy, Stanley D.; Zimmerman, Kurt J.

    2001-01-01

    Examines the higher order structure of Form G of the Myers Briggs Type Indicator. A third order component analysis of a sample (N=926) found two higher order components. This higher order analysis contributes to the research literature pertaining to the generalized structure of the personality measure. (Contains 44 references and 1 table.) (GCP)

  16. Rewritable azobenzene polyester for polarization holographic data storage

    DEFF Research Database (Denmark)

    Kerekes, A; Sajti, Sz.; Loerincz, Emoeke;

    2000-01-01

    Optical storage properties of thin azobenzene side-chain polyester films were examined by polarization holographic measurements. The new amorphous polyester film is the candidate material for the purpose of rewritable holographic memory system. Temporal formation of anisotropic and topographic...... and erasing was tested. The ability of azobenzene polyester for rewriting was found satisfactory after many writing-erasing cycles....

  17. Closed nominal rewriting and efficiently computable nominal algebra equality

    CERN Document Server

    Fernández, Maribel; 10.4204/EPTCS.34.5

    2010-01-01

    We analyse the relationship between nominal algebra and nominal rewriting, giving a new and concise presentation of equational deduction in nominal theories. With some new results, we characterise a subclass of equational theories for which nominal rewriting provides a complete procedure to check nominal algebra equality. This subclass includes specifications of the lambda-calculus and first-order logic.

  18. Infinitary Term Graph Rewriting is Simple, Sound and Complete

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2012-01-01

    Based on a simple metric and a simple partial order on term graphs, we develop two infinitary calculi of term graph rewriting. We show that, similarly to infinitary term rewriting, the partial order formalisation yields a conservative extension of the metric formalisation of the calculus. By show...

  19. Partial Order Infinitary Term Rewriting and Böhm Trees

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2010-01-01

    We investigate an alternative model of infinitary term rewriting. Instead of a metric, a partial order on terms is employed to formalise (strong) convergence. We compare this partial order convergence of orthogonal term rewriting systems to the usual metric convergence of the corresponding Böhm e...

  20. Closed nominal rewriting and efficiently computable nominal algebra equality

    Directory of Open Access Journals (Sweden)

    Maribel Fernández

    2010-09-01

    Full Text Available We analyse the relationship between nominal algebra and nominal rewriting, giving a new and concise presentation of equational deduction in nominal theories. With some new results, we characterise a subclass of equational theories for which nominal rewriting provides a complete procedure to check nominal algebra equality. This subclass includes specifications of the lambda-calculus and first-order logic.

  1. Mathematics Teachers’ Interpretation of Higher-Order Thinking in Bloom’s Taxonomy

    OpenAIRE

    Tony Thompson

    2008-01-01

    This study investigated mathematics teachers’ interpretation of higher-order thinking in Bloom’s Taxonomy. Thirty-two high school mathematics teachers from the southeast U.S. were asked to (a) define lower- and higher-order thinking, (b) identify which thinking skills in Bloom’s Taxonomy represented lower- and higher-order thinking, and (c) create an Algebra I final exam item representative of each thinking skill. Results indicate that mathematics teachers have difficulty interpreting the thi...

  2. Adaptive Integral Method for Higher-Order Hierarchical Method of Moments

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Meincke, Peter

    2006-01-01

    The Adaptive Integral Method (AIM) is applied to solve the volume integral equation in conjunction with the higher-order Method of Moments (MoM). The classical AIM is modified for larger discretization cells to take advantage of higher-order MoM. The technique combines the low computational...... complexity and memory requirements of AIM with the reduced number of unknowns and higher-order convergence of higher-order hierarchical Legendre basis functions. Numerical examples given show the advantages of the proposed technique over AIM based on low-order basis functions in terms of memory...

  3. Solution of volume-surface integral equations using higher-order hierarchical Legendre basis functions

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Meincke, Peter; Breinbjerg, Olav

    2007-01-01

    is applied to transform the VSIE into a system of linear equations. The higher-order MoM provides significant reduction in the number of unknowns in comparison with standard MoM formulations using low-order basis functions, such as RWG functions. Due to the orthogonal nature of the higher-order Legendre......The problem of electromagnetic scattering by composite metallic and dielectric objects is solved using the coupled volume-surface integral equation (VSIE). The method of moments (MoM) based on higher-order hierarchical Legendre basis functions and higher-order curvilinear geometrical elements...

  4. Probing higher order correlations of the photon field with photon number resolving avalanche photodiodes.

    Science.gov (United States)

    Dynes, J F; Yuan, Z L; Sharpe, A W; Thomas, O; Shields, A J

    2011-07-04

    We demonstrate the use of two high speed avalanche photodiodes in exploring higher order photon correlations. By employing the photon number resolving capability of the photodiodes the response to higher order photon coincidences can be measured. As an example we show experimentally the sensitivity to higher order correlations for three types of photon sources with distinct photon statistics. This higher order correlation technique could be used as a low cost and compact tool for quantifying the degree of correlation of photon sources employed in quantum information science.

  5. Simulation and Verification of Synchronous Set Relations in Rewriting Logic

    Science.gov (United States)

    Rocha, Camilo; Munoz, Cesar A.

    2011-01-01

    This paper presents a mathematical foundation and a rewriting logic infrastructure for the execution and property veri cation of synchronous set relations. The mathematical foundation is given in the language of abstract set relations. The infrastructure consists of an ordersorted rewrite theory in Maude, a rewriting logic system, that enables the synchronous execution of a set relation provided by the user. By using the infrastructure, existing algorithm veri cation techniques already available in Maude for traditional asynchronous rewriting, such as reachability analysis and model checking, are automatically available to synchronous set rewriting. The use of the infrastructure is illustrated with an executable operational semantics of a simple synchronous language and the veri cation of temporal properties of a synchronous system.

  6. Higher-Order Beta Matching with Solutions in Long Beta-Eta Normal Form

    DEFF Research Database (Denmark)

    Støvring, Kristian

    2006-01-01

    up to beta-eta equivalence is a long-standing open problem.We show that higher-order matching up to beta-eta equivalence is decidable if and only if a restricted form of higher-order matching up to beta equivalence is decidable: the restriction is that solutions must be in long beta-eta normal form....

  7. On the Higher Power Sums of Reciprocal Higher-Order Sequences

    Directory of Open Access Journals (Sweden)

    Zhengang Wu

    2014-01-01

    Full Text Available Let {un} be a higher-order linear recursive sequence. In this paper, we use the properties of error estimation and the analytic method to study the reciprocal sums of higher power of higher-order sequences. Then we establish several new and interesting identities relating to the infinite and finite sums.

  8. Analysis of Scattering by Inhomogeneous Dielectric Objects Using Higher-Order Hierarchical MoM

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Jørgensen, Erik; Meincke, Peter;

    2003-01-01

    developed higher-order hierarchical Legendre basis functions for expansion of the electric flux density and higher-order geometry modeling. An unstructured mesh composed by trilinear (8-node) and/or curved (27-node) hexahedral elements is used to represent the dielectric object accurately. It is shown...

  9. Generalized q-Euler Numbers and Polynomials of Higher Order and Some Theoretic Identities

    Directory of Open Access Journals (Sweden)

    T. Kim

    2010-01-01

    Full Text Available We give a new construction of the q-Euler numbers and polynomials of higher order attached to Dirichlet's character χ. We derive some theoretic identities involving the generalized q-Euler numbers and polynomials of higher order.

  10. Teaching Higher Order Thinking in the Introductory MIS Course: A Model-Directed Approach

    Science.gov (United States)

    Wang, Shouhong; Wang, Hai

    2011-01-01

    One vision of education evolution is to change the modes of thinking of students. Critical thinking, design thinking, and system thinking are higher order thinking paradigms that are specifically pertinent to business education. A model-directed approach to teaching and learning higher order thinking is proposed. An example of application of the…

  11. Assessing School Work Culture: A Higher-Order Analysis and Strategy.

    Science.gov (United States)

    Johnson, William L.; Johnson, Annabel M.; Zimmerman, Kurt J.

    This paper reviews a work culture productivity model and reports the development of a work culture instrument based on the culture productivity model. Higher order principal components analysis was used to assess work culture, and a third-order factor analysis shows how the first-order factors group into higher-order factors. The school work…

  12. Higher Order Thinking Skills among Secondary School Students in Science Learning

    Science.gov (United States)

    Saido, Gulistan Mohammed; Siraj, Saedah; Bin Nordin, Abu Bakar; Al Amedy, Omed Saadallah

    2015-01-01

    A central goal of science education is to help students to develop their higher order thinking skills to enable them to face the challenges of daily life. Enhancing students' higher order thinking skills is the main goal of the Kurdish Science Curriculum in the Iraqi-Kurdistan region. This study aimed at assessing 7th grade students' higher order…

  13. Teaching Higher Order Thinking in the Introductory MIS Course: A Model-Directed Approach

    Science.gov (United States)

    Wang, Shouhong; Wang, Hai

    2011-01-01

    One vision of education evolution is to change the modes of thinking of students. Critical thinking, design thinking, and system thinking are higher order thinking paradigms that are specifically pertinent to business education. A model-directed approach to teaching and learning higher order thinking is proposed. An example of application of the…

  14. From "Hello" to Higher-Order Thinking: The Effect of Coaching and Feedback on Online Chats

    Science.gov (United States)

    Stein, David S.; Wanstreet, Constance E.; Slagle, Paula; Trinko, Lynn A.; Lutz, Michelle

    2013-01-01

    This exploratory study examined the effect of a coaching and feedback intervention in teaching presence and social presence on higher-order thinking in an online community of inquiry. Coaching occurred before each chat, and feedback was provided immediately afterwards. The findings suggest that over time, the frequency of higher-order thinking…

  15. An Analysis of Higher-Order Thinking on Algebra I End-of-Course Tests

    Science.gov (United States)

    Thompson, Tony

    2011-01-01

    This research provides insight into one US state's effort to incorporate higher-order thinking on its Algebra I End-of-Course tests. To facilitate the inclusion of higher-order thinking, the state used "Dimensions of Thinking" (Marzano et al., 1988) and "Bloom's Taxonomy" (Bloom et al., 1956). An analysis of Algebra I test…

  16. Cauchy Problem for Quasilinear Hyperbolic Systems with Higher Order Dissipative Terms

    Institute of Scientific and Technical Information of China (English)

    Wei-guo Zhang

    2003-01-01

    In this paper, the author studies the global existence, singularities and life span of smooth solutions of the Cauchy problem for a class of quasilinear hyperbolic systems with higher order dissipative terms and gives their applications to nonlinear wave equations with higher order dissipative terms.

  17. From "Hello" to Higher-Order Thinking: The Effect of Coaching and Feedback on Online Chats

    Science.gov (United States)

    Stein, David S.; Wanstreet, Constance E.; Slagle, Paula; Trinko, Lynn A.; Lutz, Michelle

    2013-01-01

    This exploratory study examined the effect of a coaching and feedback intervention in teaching presence and social presence on higher-order thinking in an online community of inquiry. Coaching occurred before each chat, and feedback was provided immediately afterwards. The findings suggest that over time, the frequency of higher-order thinking…

  18. Higher order antibunching and subpossonian photon statistics in five wave mixing process

    CERN Document Server

    Verma, Amit

    2009-01-01

    We have investigated the possibility of observing higher order antibunching (HOA) and higher order subpossonian photon statistics (HOSPS) in five wave mixing and third harmonic generation process. It had been shown that both processes satisfy the criteria of HOA and HOSPS. Further, some observations on the nature of interaction which produces HOA and HOSPS are reported.

  19. Higher-order blackhole solutions in N=2 supergravity and Calabi-Yau string backgrounds

    NARCIS (Netherlands)

    Behrndt, K.; Cardoso, G.L.; de Wit, B.Q.P.J.; Lüst, D.; Mohaupt, T.; Sabra, W.A.

    1998-01-01

    Based on special geometry, we consider corrections to N=2 extremal black-hole solutions and their entropies originating from higher-order derivative terms in N=2 supergravity. These corrections are described by a holomorphic function, and the higher-order black-hole solutions can be expressed in ter

  20. An Analysis of Higher-Order Thinking on Algebra I End-of-Course Tests

    Science.gov (United States)

    Thompson, Tony

    2011-01-01

    This research provides insight into one US state's effort to incorporate higher-order thinking on its Algebra I End-of-Course tests. To facilitate the inclusion of higher-order thinking, the state used "Dimensions of Thinking" (Marzano et al., 1988) and "Bloom's Taxonomy" (Bloom et al., 1956). An analysis of Algebra I test items found that the…

  1. Ability, Breadth, and Parsimony in Computational Models of Higher-Order Cognition

    Science.gov (United States)

    Cassimatis, Nicholas L.; Bello, Paul; Langley, Pat

    2008-01-01

    Computational models will play an important role in our understanding of human higher-order cognition. How can a model's contribution to this goal be evaluated? This article argues that three important aspects of a model of higher-order cognition to evaluate are (a) its ability to reason, solve problems, converse, and learn as well as people do;…

  2. An Analysis of Higher-Order Thinking on Algebra I End-of-Course Tests

    Science.gov (United States)

    Thompson, Tony

    2011-01-01

    This research provides insight into one US state's effort to incorporate higher-order thinking on its Algebra I End-of-Course tests. To facilitate the inclusion of higher-order thinking, the state used "Dimensions of Thinking" (Marzano et al., 1988) and "Bloom's Taxonomy" (Bloom et al., 1956). An analysis of Algebra I test…

  3. Construction of special eye models for investigation of chromatic and higher-order aberrations of eyes.

    Science.gov (United States)

    Zhai, Yi; Wang, Yan; Wang, Zhaoqi; Liu, Yongji; Zhang, Lin; He, Yuanqing; Chang, Shengjiang

    2014-01-01

    An achromatic element eliminating only longitudinal chromatic aberration (LCA) while maintaining transverse chromatic aberration (TCA) is established for the eye model, which involves the angle formed by the visual and optical axis. To investigate the impacts of higher-order aberrations on vision, the actual data of higher-order aberrations of human eyes with three typical levels are introduced into the eye model along visual axis. Moreover, three kinds of individual eye models are established to investigate the impacts of higher-order aberrations, chromatic aberration (LCA+TCA), LCA and TCA on vision under the photopic condition, respectively. Results show that for most human eyes, the impact of chromatic aberration on vision is much stronger than that of higher-order aberrations, and the impact of LCA in chromatic aberration dominates. The impact of TCA is approximately equal to that of normal level higher-order aberrations and it can be ignored when LCA exists.

  4. Numerical Models of Higher-Order Boussinesq Equations and Comparisons with Laboratory Measurement

    Institute of Scientific and Technical Information of China (English)

    邹志利; 张晓莉

    2001-01-01

    Nonlinear water wave propagation passing a submerged shelf is studied experimentally and numerically. The applicability of two different wave propagation models has been investigated. One is higher-order Boussinesq equationsderived by Zou (1999) and the other is the classic Boussinesq equations. Physical experiments are conducted, three differ-ent front slopes (1:10, 1:5 and 1:2) of the shelf are set up in the experiment and their effects on wave propagation are in-vestigated. Comparisons of numerical results with test data are made, the model of higher-order Boussinesq equationsagrees much better with the measurements than the model of the classical Boussinesq equations. The results show thatthe higher-order Boussinesq equations can also be applied to the steeper slope case although the mild slope assumption isemployed in the derivation of the higher order terms of higher order Boussinesq equations.

  5. Optimal Control and higher-order mechanics for systems with symmetries

    CERN Document Server

    Colombo, Leonardo; de Diego, David Martin

    2012-01-01

    In this paper we will develop and design numerical methods for optimal control problems for a class of underactuated Lagrangian mechanical systems where the configuration manifold is a trivial principal bundle . We will construct these geometric integrators using discrete variational calculus, deriving a discrete version of the higher-order Euler-Lagrange equations on trivial principal bundles. The analysis applies to systems subject to higher-order constraints (that is, depending of higher-order derivatives as, for example, the acceleration). Interesting applications as, for instance, a discrete derivation of the Euler-Lagrange equations for higher-order Lagrangians and higher-order reduced Lagrangians, respectively, are shown. We find interesting applications both in the optimal control of an underactuated vehicle and the well-known plate ball problem seen as an optimization problem with nonholonomic constraints .

  6. Tunneling dynamics of Bose-Einstein condensates with higher-order interactions in optical lattice

    Institute of Scientific and Technical Information of China (English)

    Tie Lu; Xue Ju-Kui

    2011-01-01

    The nonlinear Landau-Zener tunneling and nonlinear Rabi oscillations of Bose-Einstein condensate (BEC) with higher-order atomic interaction between the Bloch bands in an accelerating optical lattice are discussed.Within the two-level model,the tunneling probability of BEC with higher-order atomic interaction between Bloch bands is obtained.We finds that the tunneling rate is closely related to the higher-order atomic interaction.Furthermore,the nonlinear Rabi oscillations of BEC with higher-order atomic interaction between the bands are discussed by imposing a periodic modulation on the level bias.Analytical expressions of the critical higher-order atomic interaction for suppressing/enhancing the Rabi oscillations are obtained.It is shown that the critical value strongly depends on the modulation parameters (i.e.,the modulation amplitude and frequency) and the strength of periodic potential.

  7. Mathematics Teachers’ Interpretation of Higher-Order Thinking in Bloom’s Taxonomy

    Directory of Open Access Journals (Sweden)

    Tony Thompson

    2008-07-01

    Full Text Available This study investigated mathematics teachers’ interpretation of higher-order thinking in Bloom’s Taxonomy. Thirty-two high school mathematics teachers from the southeast U.S. were asked to (a define lower- and higher-order thinking, (b identify which thinking skills in Bloom’s Taxonomy represented lower- and higher-order thinking, and (c create an Algebra I final exam item representative of each thinking skill. Results indicate that mathematics teachers have difficulty interpreting the thinking skills in Bloom’s Taxonomy and creating test items for higher-order thinking. Alternatives to using Bloom’s Taxonomy to help mathematics teachers assess for higher-order thinking are discussed.

  8. Bose-Einstein Condensates in Optical Lattices with Higher-Order Interactions

    Institute of Scientific and Technical Information of China (English)

    张爱霞; 薛具奎

    2012-01-01

    The higher-order interactions of Bose-Einstein condensate in multi-dimensional optical lattices are discussed both analytically and numerically.It is demonstrated that the effects of the higher-order atomic interactions on the sound speed and the stabilities of Bloch waves strongly depend on the lattice strength.In the presence of higher-order effects,tighter and high-dimensional lattices are confirmed to be two positive factors for maintaining the system's energetic stability,and the dynamical instability of Bloch waves can take place simultaneously with the energetic instability.In addition,we find that the higher-order interactions exhibit a long-range behavior and the long-lived coherent Bloch oscillations in a tilted optical lattice exist.Our results provide an effective way to probe the higher-order interactions in optical lattices.

  9. Vision improvement by correcting higher-order aberrations with customized soft contact lenses in keratoconic eyes

    Science.gov (United States)

    Sabesan, Ramkumar; Jeong, Tae Moon; Carvalho, Luis; Cox, Ian G.; Williams, David R.; Yoon, Geunyoung

    2007-04-01

    Higher-order aberration correction in abnormal eyes can result in significant vision improvement, especially in eyes with abnormal corneas. Customized optics such as phase plates and customized contact lenses are one of the most practical, nonsurgical ways to correct these ocular higher-order aberrations. We demonstrate the feasibility of correcting higher-order aberrations and improving visual performance with customized soft contact lenses in keratoconic eyes while compensating for the static decentration and rotation of the lens. A reduction of higher-order aberrations by a factor of 3 on average was obtained in these eyes. The higher-order aberration correction resulted in an average improvement of 2.1 lines in visual acuity over the conventional correction of defocus and astigmatism alone.

  10. Well limit behaviors of term rewriting systems

    Institute of Scientific and Technical Information of China (English)

    MA Shilong; SUI Yuefei; XU Ke

    2007-01-01

    The limit behaviors of computations have not been fully explored.It is necessary to consider such limit behaviors when we consider the properties of infinite objects in computer science,such as infinite logic programs,the symbolic solutions of infinite polynomial equations.Usually,we can use finite objects to approximate infinite objects,and we should know what kinds of infinite objects are approximable and how to approximate them effectively.A sequence {Rκ:κω}of term rewriting systems has the well limit behavior if under the condition that the sequence has the Set-theoretic limit or the distance-based limit,the sequence {Th(Rκ):κ∈ω} of corresponding theoretic closures of Rκ has the set-theoretic or distance-based limit,and limκ→∞ Th(Rκ) is equal to the theoretic closure of the limit of {Rκ:κ∈ω).Two kinds of limits of term rewriting systems are considered:one is based on the set-theoretic limit,the other is on the distance-based limit.It is proved thatgiven a sequence {Rκ:κ∈ω) of term rewriting systems Rκ,if there is a well-founded ordering (-<) on terms such that every Rκ is (-<)-well-founded,and the set-theoretic limit of {Rκ:κ∈ω).exists,then {Rκ:κ∈ω).has the well limit behavior;and if (1) there is a well-founded ordering(-<)on terms such that every Rκ is(-<-well-founded,(2) there is a distance d on terms which is closed under substitutions and contexts and (3) {Rκ:κ∈ω).is Cauchy under d then {Rκ:κ∈ω).has the well limit behavior.The results are used to approximate the least Herbrand models of infinite Horn logic programs and real Horn logic programs,and the solutions and Cr(o)bner bases of (infinite) sets of real polynomials by sequences of (finite) sets of rational polynomials.

  11. Differences in response to serotonergic activation between first and higher order thalamic nuclei.

    Science.gov (United States)

    Varela, C; Sherman, S Murray

    2009-08-01

    Two types of thalamic nuclei have been recognized: first order, which relay information from subcortical sources, and higher order, which may relay information from one cortical area to another. We have recently shown that muscarinic agonists depolarize all first order and most higher order relay cells but hyperpolarize a significant proportion of higher order relay cells. We now extend this result to serotonergic agonists, using rat thalamic brain slices and whole-cell, current- and voltage-clamp recordings from relay cells in various first order (the lateral geniculate nucleus, the ventral posterior nucleus, and the ventral portion of the medial geniculate body) and higher order nuclei (the lateral posterior, the posterior medial nucleus, and the dorsal portion of the medial geniculate body). Similar to the effects of muscarinic agonists, we found that first and most higher order relay cells were depolarized by serotonergic agonists, but 15% of higher order relay cells responded with hyperpolarization. Thus different subsets of higher order relay cells are hyperpolarized by these modulatory systems, which could have implications for the transfer of information between cortical areas.

  12. Geometric Integrators for Higher-Order Variational Systems and Their Application to Optimal Control

    Science.gov (United States)

    Colombo, Leonardo; Ferraro, Sebastián; Martín de Diego, David

    2016-12-01

    Numerical methods that preserve geometric invariants of the system, such as energy, momentum or the symplectic form, are called geometric integrators. In this paper we present a method to construct symplectic-momentum integrators for higher-order Lagrangian systems. Given a regular higher-order Lagrangian L:T^{(k)}Q→ R with k≥ 1, the resulting discrete equations define a generally implicit numerical integrator algorithm on T^{(k-1)}Q× T^{(k-1)}Q that approximates the flow of the higher-order Euler-Lagrange equations for L. The algorithm equations are called higher-order discrete Euler-Lagrange equations and constitute a variational integrator for higher-order mechanical systems. The general idea for those variational integrators is to directly discretize Hamilton's principle rather than the equations of motion in a way that preserves the invariants of the original system, notably the symplectic form and, via a discrete version of Noether's theorem, the momentum map. We construct an exact discrete Lagrangian L_d^e using the locally unique solution of the higher-order Euler-Lagrange equations for L with boundary conditions. By taking the discrete Lagrangian as an approximation of L_d^e, we obtain variational integrators for higher-order mechanical systems. We apply our techniques to optimal control problems since, given a cost function, the optimal control problem is understood as a second-order variational problem.

  13. Influence of cosmetically tinted soft contact lenses on higher-order wavefront aberrations and visual performance.

    Science.gov (United States)

    Hiraoka, Takahiro; Ishii, Yuko; Okamoto, Fumiki; Oshika, Tetsuro

    2009-02-01

    To investigate the influence of cosmetically tinted soft contact lenses on ocular higher-order aberrations and visual performance, and to analyze the relationship between these parameters after the lens wear. In 44 eyes of 22 subjects, visual acuity, contrast sensitivity under photopic and mesopic conditions, and ocular higher-order aberrations were evaluated before and after wearing the tinted soft contact lenses (1-day Acuvue Colours; Vistakon, Jacksonville, FL). Contrast sensitivity under a photopic condition was determined at 3, 6, 12, and 18 cycles per degree, and the area under the log contrast sensitivity function (AULCSF) was calculated. Mesopic contrast sensitivity with and without glare was assessed. Ocular higher-order aberrations for a 4-mm pupil were measured, and coma-like, spherical-like, and total higher-order aberrations were determined. The tinted contact lens wearing resulted in significant decreases in log contrast sensitivity at all spatial frequencies (P 0.05), the changes in total higher-order aberrations showed a significant correlation with those in AULCSF (P 0.05). Cosmetically tinted contact lenses increase ocular higher-order aberrations and worsen contrast sensitivity under both photopic and mesopic conditions. Increases in higher-order aberrations are responsible for decreased contrast sensitivity under the photopic condition. Tinted contact lens wearers should be sufficiently informed about the possible reduction in optical quality of the eye and quality of vision.

  14. Higher-Order Smoothing:A Novel Semantic Smoothing Method for Text Classification

    Institute of Scientific and Technical Information of China (English)

    Mitat Poyraz; Zeynep Hilal Kilimci; Murat Can Ganiz

    2014-01-01

    It is known that latent semantic indexing (LSI) takes advantage of implicit higher-order (or latent) structure in the association of terms and documents. Higher-order relations in LSI capture “latent semantics”. These findings have inspired a novel Bayesian framework for classification named Higher-Order Naive Bayes (HONB), which was introduced previously, that can explicitly make use of these higher-order relations. In this paper, we present a novel semantic smoothing method named Higher-Order Smoothing (HOS) for the Naive Bayes algorithm. HOS is built on a similar graph based data representation of the HONB which allows semantics in higher-order paths to be exploited. We take the concept one step further in HOS and exploit the relationships between instances of different classes. As a result, we move beyond not only instance boundaries, but also class boundaries to exploit the latent information in higher-order paths. This approach improves the parameter estimation when dealing with insufficient labeled data. Results of our extensive experiments demonstrate the value of HOS on several benchmark datasets.

  15. Solving Nonstiff Higher Order Odes Using Variable Order Step Size Backward Difference Directly

    Directory of Open Access Journals (Sweden)

    Ahmad Fadly Nurullah Rasedee

    2014-01-01

    Full Text Available The current numerical techniques for solving a system of higher order ordinary differential equations (ODEs directly calculate the integration coefficients at every step. Here, we propose a method to solve higher order ODEs directly by calculating the integration coefficients only once at the beginning of the integration and if required once more at the end. The formulae will be derived in terms of backward difference in a constant step size formulation. The method developed will be validated by solving some higher order ODEs directly using variable order step size. To simplify the evaluations of the integration coefficients, we find the relationship between various orders. The results presented confirmed our hypothesis.

  16. Higher order capacity statistics of multi-hop transmission systems over Rayleigh fading channels

    KAUST Repository

    Yilmaz, Ferkan

    2012-03-01

    In this paper, we present an exact analytical expression to evaluate the higher order statistics of the channel capacity for amplify and forward (AF) multihop transmission systems operating over Rayleigh fading channels. Furthermore, we present simple and efficient closed-form expression to the higher order moments of the channel capacity of dual hop transmission system with Rayleigh fading channels. In order to analyze the behavior of the higher order capacity statistics and investigate the usefulness of the mathematical analysis, some selected numerical and simulation results are presented. Our results are found to be in perfect agreement. © 2012 IEEE.

  17. Verifying object-oriented programs with higher-order separation logic in Coq

    DEFF Research Database (Denmark)

    Bengtson, Jesper; Jensen, Jonas Braband; Sieczkowski, Filip;

    2011-01-01

    We present a shallow Coq embedding of a higher-order separation logic with nested triples for an object-oriented programming language. Moreover, we develop novel specification and proof patterns for reasoning in higher-order separation logic with nested triples about programs that use interfaces...... and interface inheritance. In particular, we show how to use the higher-order features of the Coq formalisation to specify and reason modularly about programs that (1) depend on some unknown code satisfying a specification or that (2) return objects conforming to a certain specification. All of our results have...

  18. Mapping Modular SOS to Rewriting Logic

    DEFF Research Database (Denmark)

    Braga, Christiano de Oliveira; Haeusler, Erik Hermann; Meseguer, José;

    Modular SOS (MSOS) is a framework created to improve the modularity of structural operational semantics specifications, a formalism frequently used in the fields of programming languages semantics and process algebras. With the objective of defining formal tools to support the execution and verif......-performance implementation of RWL. In this paper we characterize the mapping and the MSOS-SL Interpreter. The reader is assumed to have some basic knowledge of structural operational semantics and object-oriented concepts....... and verification of MSOS specifications, we have defined a mapping, named , from MSOS to rewriting logic (RWL), a logic which has been proposed as a logical and semantic framework. We have proven the correctness of and implemented it as a prototype, the MSOS-SL Interpreter, in the Maude system, a high...

  19. Directed animals, quadratic and rewriting systems

    CERN Document Server

    Marckert, Jean-François

    2011-01-01

    A directed animal is a percolation cluster in the directed site percolation model. The aim of this paper is to exhibit a strong relation between in one hand, the problem of computing the generating function $\\G$ of directed animals on the square lattice, counted according to the area and the perimeter, and on the other hand, the problem to find a solution to a system of quadratic equations involving unknown matrices. The matrices solution of this problem can be finite or infinite. We were unable to find finite solutions. We present some solid clues that some infinite explicit matrices, fix points of a rewriting like system are the natural solutions of this system of equations: some strong evidences are given that the problem of finding $\\G$ reduces then to the problem of finding an eigenvector to an explicit infinite matrix. Similar properties are shown for other combinatorial questions concerning directed animals, and for different lattices.

  20. Elementary Particle Spectroscopy in Regular Solid Rewrite

    Science.gov (United States)

    Trell, Erik

    2008-10-01

    The Nilpotent Universal Computer Rewrite System (NUCRS) has operationalized the radical ontological dilemma of Nothing at All versus Anything at All down to the ground recursive syntax and principal mathematical realisation of this categorical dichotomy as such and so governing all its sui generis modalities, leading to fulfilment of their individual terms and compass when the respective choice sequence operations are brought to closure. Focussing on the general grammar, NUCRS by pure logic and its algebraic notations hence bootstraps Quantum Mechanics, aware that it "is the likely keystone of a fundamental computational foundation" also for e.g. physics, molecular biology and neuroscience. The present work deals with classical geometry where morphology is the modality, and ventures that the ancient regular solids are its specific rewrite system, in effect extensively anticipating the detailed elementary particle spectroscopy, and further on to essential structures at large both over the inorganic and organic realms. The geodetic antipode to Nothing is extension, with natural eigenvector the endless straight line which when deployed according to the NUCRS as well as Plotelemeian topographic prescriptions forms a real three-dimensional eigenspace with cubical eigenelements where observed quark-skewed quantum-chromodynamical particle events self-generate as an Aristotelean phase transition between the straight and round extremes of absolute endlessness under the symmetry- and gauge-preserving, canonical coset decomposition SO(3)×O(5) of Lie algebra SU(3). The cubical eigen-space and eigen-elements are the parental state and frame, and the other solids are a range of transition matrix elements and portions adapting to the spherical root vector symmetries and so reproducibly reproducing the elementary particle spectroscopy, including a modular, truncated octahedron nano-composition of the Electron which piecemeal enter into molecular structures or compressed to each

  1. Time-periodic Solution to a Nonlinear Parabolic Type Equation of Higher Order

    Institute of Scientific and Technical Information of China (English)

    Yan-ping Wang; You-lin Zhang

    2008-01-01

    In this paper, the existence and uniqueness of time-periodic generalized solutions and time-periodic classical solutions to a class of parabolic type equation of higher order are proved by Gaierkin method.

  2. The Need to Deliver Higher-Order Skills in the Context of Marketing in SMEs

    Science.gov (United States)

    Copley, Paul

    2013-01-01

    It is argued that the delivery of learning and the development of skills and competences are central to SME success; and there appears to be a requirement for higher-order education and training that can deliver a

  3. Higher-Order Squeezing in a Boson Coupled Two-Mode System

    Science.gov (United States)

    Chizhov, A. V.; Haus, J. W.; Yeong, K. C.

    1996-01-01

    We consider a model for nondegenerate cavity fields interacting through an intervening Boson field. The quantum correlations introduced in this manner are manifest through their higher-order correlation functions where a type of squeezed state is identified.

  4. Deformation from symmetry for Schrodinger equations of higher order on unbounded domains

    Directory of Open Access Journals (Sweden)

    Addolorata Salvatore

    2003-06-01

    Full Text Available By means of a perturbation method recently introduced by Bolle, we discuss the existence of infinitely many solutions for a class of perturbed symmetric higher order Schrodinger equations with non-homogeneous boundary data on unbounded domains.

  5. Superpositions of higher-order bessel beams and nondiffracting speckle fields - (SAIP 2009)

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2009-07-01

    Full Text Available This poster presents a mechanism for the generation of the superposition of higher-order Bessel beams, which implements a ring slit aperture and spatial light modulator (SLM). The experimental technique is also adapted to generate nondiffracting...

  6. Generalizing higher-order Bessel-Gauss beams: analytical description and demonstration.

    Science.gov (United States)

    Schimpf, Damian N; Schulte, Jan; Putnam, William P; Kärtner, Franz X

    2012-11-19

    We report on a novel class of higher-order Bessel-Gauss beams in which the well-known Bessel-Gauss beam is the fundamental mode and the azimuthally symmetric Laguerre-Gaussian beams are special cases. We find these higher-order Bessel-Gauss beams by superimposing decentered Hermite-Gaussian beams. We show analytically and experimentally that these higher-order Bessel-Gauss beams resemble higher-order eigenmodes of optical resonators consisting of aspheric mirrors. This work is relevant for the many applications of Bessel-Gauss beams in particular the more recently proposed high-intensity Bessel-Gauss enhancement cavities for strong-field physics applications.

  7. Beam interactions with surface waves and higher-order modes in oversized backward wave oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Ogura, Kazuo; Kojima, Akihiko; Kawabe, Fumiaki; Yambe, Kiyoyuki [Niigata University, Niigata (Japan); Amin, Ruhul [Islamic University of Technology, Gazipur (Bangladesh)

    2014-10-15

    Beam interactions with surface waves and higher-order modes in an oversized backward wave oscillator (BWO) are studied. In addition to the well-known Cherenkov interaction, the slow cyclotron interaction occurs due to transverse perturbations of the electron beam. The Cherenkov interaction dominates the slow cyclotron interaction. Growth rates of both the interactions for the higher order modes are small compared with those for the surface-wave modes in an oversized BWO. The coaxial slow-wave structure exhibits a reduced number of higher-order modes, which consequently reduces the mode competition problem and improves beam interactions with higher order modes. For higher values of beam currents, the slow cyclotron wave grows at a faster rate than the Cherenkov waves.

  8. A new approach for global controllability of higher order Boolean control network.

    Science.gov (United States)

    Chen, Hao; Sun, Jitao

    2013-03-01

    Using the semi-tensor product, the global control problem of the higher order Boolean control network with avoiding set is considered. First, the number of different control sequences that drive the higher order Boolean control network from the initial state to the destination state while avoiding undesirable set is provided. Then, the definition of global controllability of higher order Boolean control network is given. Third, by using the classical theory of nonnegative matrices, the necessary and sufficient condition for the global controllability of higher order Boolean control network with avoiding set is presented. Furthermore, a sufficient condition for k fixed-time global controllability of the system is also obtained. At last, an example is given to illustrate the main results.

  9. STRATEGIES FOR IMPROVING HIGHER ORDER THINKING SKILLS IN TEACHING AND LEARNING OF DESIGN AND TECHNOLOGY EDUCATION

    Directory of Open Access Journals (Sweden)

    Caleb Chidozie Chinedu

    2015-12-01

    Full Text Available Higher order thinking skills (HOTS should be an integral part of teaching and learning especially at the higher education level. Thinking skills lessons should be part of the curriculum if students are to solve problems individually, cooperatively and creatively. Teachers on the other hand must be conversant with relevant techniques needed for teaching higher order thinking. An in-depth review of literature reveals that teachers are faced with the problem of how to prepare and teach higher order thinking skills in design and technology education. This paper is a library based work; and data were collected from textbooks, journal articles and internet search. The paper critically examined existing practices in the teaching of higher order thinking skills in design and technology education. Some of the key features mentioned were the use of concept, inferences, visualization, and schemas, among others. Recommendations for practice change were made regarding the development of HOTS.

  10. Visualization and processing of higher order descriptors for multi-valued data

    CERN Document Server

    Schultz, Thomas

    2015-01-01

    Modern imaging techniques and computational simulations yield complex multi-valued data that require higher-order mathematical descriptors. This book addresses topics of importance when dealing with such data, including frameworks for image processing, visualization, and statistical analysis of higher-order descriptors. It also provides examples of the successful use of higher-order descriptors in specific applications and a glimpse of the next generation of diffusion MRI. To do so, it combines contributions on new developments, current challenges in this area, and state-of-the-art surveys.   Compared to the increasing importance of higher-order descriptors in a range of applications, tools for analysis and processing are still relatively hard to come by. Even though application areas such as medical imaging, fluid dynamics, and structural mechanics are very different in nature they face many shared challenges. This book provides an interdisciplinary perspective on this topic with contributions from key rese...

  11. MULTIPLE POSITIVE SOLUTIONS TO BVPS FOR HIGHER ORDER NONLINEAR DIFFERENTIAL EQUATIONS IN BANACH SPACES

    Institute of Scientific and Technical Information of China (English)

    戚仕硕

    2001-01-01

    In this article,the author employs the conical expansion and compression fixed point principle and the fixed point index theory to show that there exist at least two positive solutions for a higher order BVP.

  12. A Content Analysis of General Chemistry Laboratory Manuals for Evidence of Higher-Order Cognitive Tasks

    Science.gov (United States)

    Domin, Daniel S.

    1999-01-01

    The science laboratory instructional environment is ideal for fostering the development of problem-solving, manipulative, and higher-order thinking skills: the skills needed by today's learner to compete in an ever increasing technology-based society. This paper reports the results of a content analysis of ten general chemistry laboratory manuals. Three experiments from each manual were examined for evidence of higher-order cognitive activities. Analysis was based upon the six major cognitive categories of Bloom's Taxonomy of Educational Objectives: knowledge, comprehension, application, analysis, synthesis, and evaluation. The results of this study show that the overwhelming majority of general chemistry laboratory manuals provide tasks that require the use of only the lower-order cognitive skills: knowledge, comprehension, and application. Two of the laboratory manuals were disparate in having activities that utilized higher-order cognition. I describe the instructional strategies used within these manuals to foster higher-order cognitive development.

  13. Ultra-compact Higher-Order-Mode Pass Filter in a Silicon Waveguide

    DEFF Research Database (Denmark)

    Guan, Xiaowei; Frandsen, Lars Hagedorn; Ding, Yunhong

    2015-01-01

    An 3.7 μm long higher-order-mode pass filter with an extinction ratio larger than 20 dB is demonstrated in a 1D corrugated silicon multimode waveguide......An 3.7 μm long higher-order-mode pass filter with an extinction ratio larger than 20 dB is demonstrated in a 1D corrugated silicon multimode waveguide...

  14. Higher-order terms in sensitivity analysis through a differential approach

    Energy Technology Data Exchange (ETDEWEB)

    Dubi, A.; Dudziak, D.J.

    1981-06-01

    A differential approach to sensitivity analysis has been developed that eliminates some difficulties existing in previous work. The new development leads to simple explicit expressions for the first-order perturbation as well as any higher-order terms. The higher-order terms are dependent only on differentials of the transport operator, the unperturbed flux, the adjoint flux, and the unperturbed Green's function of the system.

  15. On higher order radiative corrections to elastic electron–proton scattering

    Energy Technology Data Exchange (ETDEWEB)

    Arbuzov, A. B., E-mail: arbuzov@theor.jinr.ru [Bogoliubov Laboratory of Theoretical Physics, JINR, 141980, Dubna (Russian Federation); Department of Higher Mathematics, Dubna State University, 141982, Dubna (Russian Federation); Kopylova, T. V. [Department of Higher Mathematics, Dubna State University, 141982, Dubna (Russian Federation)

    2015-12-18

    QED radiative corrections to elastic electron–proton scattering at low energies are discussed. Corrections to the electron line and effects due to vacuum polarization are computed. Higher order effects are estimated for the conditions of the experiment on the electric and magnetic proton form factors by the A1 Collaboration. Calculations are performed within the next-to-leading approximation. The inclusion of the higher order effects can affect the value of the proton charge radius extracted from the experimental data.

  16. On higher order radiative corrections to elastic electron-proton scattering

    Energy Technology Data Exchange (ETDEWEB)

    Arbuzov, A.B. [Bogoliubov Laboratory of Theoretical Physics, Dubna (Russian Federation); Dubna State University, Department of Higher Mathematics, Dubna (Russian Federation); Kopylova, T.V. [Dubna State University, Department of Higher Mathematics, Dubna (Russian Federation)

    2015-12-15

    QED radiative corrections to elastic electron-proton scattering at low energies are discussed. Corrections to the electron line and effects due to vacuum polarization are computed. Higher order effects are estimated for the conditions of the experiment on the electric and magnetic proton form factors by the A1 Collaboration. Calculations are performed within the next-to-leading approximation. The inclusion of the higher order effects can affect the value of the proton charge radius extracted from the experimental data. (orig.)

  17. PRECONDITIONING HIGHER ORDER FINITE ELEMENT SYSTEMS BY ALGEBRAIC MULTIGRID METHOD OF LINEAR ELEMENTS

    Institute of Scientific and Technical Information of China (English)

    Yun-qing Huang; Shi Shu; Xi-jun Yu

    2006-01-01

    We present and analyze a robust preconditioned conjugate gradient method for the higher order Lagrangian finite element systems of a class of elliptic problems. An auxiliary linear element stiffness matrix is chosen to be the preconditioner for higher order finite elements. Then an algebraic multigrid method of linear finite element is applied for solving the preconditioner. The optimal condition number which is independent of the mesh size is obtained. Numerical experiments confirm the efficiency of the algorithm.

  18. Higher order mode of a microstripline fed cylindrical dielectric resonator antenna

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A. V. Praveen, E-mail: praveen.kumar@pilani.bits-pilani.ac.in [Department of Electrical and Electronics Engineering, BITS Pilani, Pilani, Rajasthan-333 031 (India)

    2016-03-09

    A microstrip transmission line can be used to excite the broadside radiating mode of a cylindrical dielectric resonator antenna (CDRA). The same is found to excite considerably well a higher order mode (HOM) as well. However unlike the broadside mode, the higher order mode gives distorted radiation pattern which makes this mode less useful for practical applications. The cause of distortion in the HOM radiation and the dependence of HOM coupling on the microstrip feed line are explored using HFSS simulations.

  19. Higher-order Schrödinger and Hartree–Fock equations

    Energy Technology Data Exchange (ETDEWEB)

    Carles, Rémi, E-mail: Remi.Carles@math.cnrs.fr [IMAG, UMR5149, CNRS and University Montpellier, CC051, 34095 Montpellier (France); Lucha, Wolfgang, E-mail: Wolfgang.Lucha@oeaw.ac.at [Institute for High Energy Physics, Austrian Academy of Sciences, Nikolsdorfergasse 18, A-1050 Vienna (Austria); Moulay, Emmanuel, E-mail: emmanuel.moulay@univ-poitiers.fr [XLIM (UMR-CNRS 7252), University Poitiers, 11 Blvd. Marie et Pierre Curie, BP 30179, 86962 Futuroscope Chasseneuil Cedex (France)

    2015-12-15

    The domain of validity of the higher-order Schrödinger equations is analyzed for harmonic-oscillator and Coulomb potentials as typical examples. Then, the Cauchy theory for higher-order Hartree–Fock equations with bounded and Coulomb potentials is developed. Finally, the existence of associated ground states for the odd-order equations is proved. This renders these quantum equations relevant for physics.

  20. An undular bore solution for the higher-order Korteweg-de Vries equation

    Energy Technology Data Exchange (ETDEWEB)

    Marchant, T R [School of Mathematics and Applied Statistics, University of Wollongong, Wollongong, 2522, NSW (Australia); Smyth, N F [School of Mathematics, University of Edinburgh, The King' s Buildings, Mayfield Road, Edinburgh, EH9 3JZ (United Kingdom)

    2006-09-15

    Undular bores describe the evolution and smoothing out of an initial step in mean height and are frequently observed in both oceanographic and meteorological applications. The undular bore solution for the higher-order Korteweg-de Vries (KdV) equation is derived, using an asymptotic transformation which relates the KdV equation and its higher-order counterpart. The higher-order KdV equation considered includes all possible third-order correction terms (where the KdV equation retains second-order terms). The asymptotic transformation is then applied to the KdV undular bore solution to obtain the higher-order undular bore. Examples of higher-order undular bores, describing both surface and internal waves, are presented. Key properties, such as the amplitude and speed of the lead soliton and the width of the bore, are found. An excellent comparison is obtained between the analytical and numerical solutions. Also, it is illustrated how an asymptotic transformation and numerical solutions can be combined to generate hybrid asymptotic-numerical solutions, thus avoiding the severe instabilities associated with numerical schemes for the higher-order KdV equation. (letter to the editor)

  1. Questions for assessing higher-order cognitive skills: it's not just Bloom's.

    Science.gov (United States)

    Lemons, Paula P; Lemons, J Derrick

    2013-01-01

    We present an exploratory study of biologists' ideas about higher-order cognition questions. We documented the conversations of biologists who were writing and reviewing a set of higher-order cognition questions. Using a qualitative approach, we identified the themes of these conversations. Biologists in our study used Bloom's Taxonomy to logically analyze questions. However, biologists were also concerned with question difficulty, the length of time required for students to address questions, and students' experience with questions. Finally, some biologists demonstrated an assumption that questions should have one correct answer, not multiple reasonable solutions; this assumption undermined their comfort with some higher-order cognition questions. We generated a framework for further research that provides an interpretation of participants' ideas about higher-order questions and a model of the relationships among these ideas. Two hypotheses emerge from this framework. First, we propose that biologists look for ways to measure difficulty when writing higher-order questions. Second, we propose that biologists' assumptions about the role of questions in student learning strongly influence the types of higher-order questions they write.

  2. A reduced-rank approach for implementing higher-order Volterra filters

    Science.gov (United States)

    O. Batista, Eduardo L.; Seara, Rui

    2016-12-01

    The use of Volterra filters in practical applications is often limited by their high computational burden. To cope with this problem, many strategies for implementing Volterra filters with reduced complexity have been proposed in the open literature. Some of these strategies are based on reduced-rank approaches obtained by defining a matrix of filter coefficients and applying the singular value decomposition to such a matrix. Then, discarding the smaller singular values, effective reduced-complexity Volterra implementations can be obtained. The application of this type of approach to higher-order Volterra filters (considering orders greater than 2) is however not straightforward, which is especially due to some difficulties encountered in the definition of higher-order coefficient matrices. In this context, the present paper is devoted to the development of a novel reduced-rank approach for implementing higher-order Volterra filters. Such an approach is based on a new form of Volterra kernel implementation that allows decomposing higher-order kernels into structures composed only of second-order kernels. Then, applying the singular value decomposition to the coefficient matrices of these second-order kernels, effective implementations for higher-order Volterra filters can be obtained. Simulation results are presented aiming to assess the effectiveness of the proposed approach.

  3. Higher order aberrations in amblyopic children and their role in refractory amblyopia

    Directory of Open Access Journals (Sweden)

    Arnaldo Dias-Santos

    2014-12-01

    Full Text Available Objective: Some studies have hypothesized that an unfavourable higher order aberrometric profile could act as an amblyogenic mechanism and may be responsible for some amblyopic cases that are refractory to conventional treatment or cases of “idiopathic” amblyopia. This study compared the aberrometric profile in amblyopic children to that of children with normal visual development and compared the aberrometric profile in corrected amblyopic eyes and refractory amblyopic eyes with that of healthy eyes. Methods: Cross-sectional study with three groups of children – the CA group (22 eyes of 11 children with unilateral corrected amblyopia, the RA group (24 eyes of 13 children with unilateral refractory amblyopia and the C group (28 eyes of 14 children with normal visual development. Higher order aberrations were evaluated using an OPD-Scan III (NIDEK. Comparisons of the aberrometric profile were made between these groups as well as between the amblyopic and healthy eyes within the CA and RA groups. Results: Higher order aberrations with greater impact in visual quality were not significantly higher in the CA and RA groups when compared with the C group. Moreover, there were no statistically significant differences in the higher order aberrometric profile between the amblyopic and healthy eyes within the CA and RA groups. Conclusions: Contrary to lower order aberrations (e.g., myopia, hyperopia, primary astigmatism, higher order aberrations do not seem to be involved in the etiopathogenesis of amblyopia. Therefore, these are likely not the cause of most cases of refractory amblyopia.

  4. Performance of Higher Order Campbell methods, Part II: calibration and experimental application

    Science.gov (United States)

    Elter, Zs.; de Izarra, G.; Filliatre, P.; Jammes, C.; Pázsit, I.

    2016-11-01

    Applying Higher Order Campbelling methods in neutron flux monitoring with fission chambers is advantageous due to their capabilities to suppress the impact of unwanted noises and signal contributions (such as gamma radiation). This work aims to verify through experimental results that the basic assumptions behind the Higher Order Campelling methods are valid in critical reactors. The experiments, reported in this work, were performed at the MINERVE reactor in Cadarache. It is shown that the calibration of a fission chamber and the associated electronic system is possible in higher order mode. With the use of unbiased cumulant estimators and with digital processing, it is shown that over a wide count rate range, accurate count rate estimation can be achieved based on signal samples of a few ms, which is a significant progress compared to similar experimental results in the literature. The difference between the count rate estimated by pulse counting and by the Higher Order Campelling is less than 4%. The work also investigates the possibility of monitoring transient events. For this purpose, a control rod drop event was followed in Higher Order Campbelling mode.

  5. Novel Object Exploration as a Potential Assay for Higher Order Repetitive Behaviors in Mice.

    Science.gov (United States)

    Steinbach, Jessica M; Garza, Elizabeth T; Ryan, Bryce C

    2016-08-20

    Restricted, repetitive behaviors (RRBs) are a core feature of autism spectrum disorder (ASD) and disrupt the lives of affected individuals. RRBs are commonly split into lower-order and higher-order components, with lower order RRBs consisting of motor stereotypies and higher order RRBs consisting of perseverative and sequencing behaviors. Higher order RRBs are challenging to model in mice. Current assays for RRBs in mice focus primarily on the lower order components, making basic biomedical research into potential treatments or interventions for higher-order RRBs difficult. Here we describe a new assay, novel object exploration. This assay uses a basic open-field arena with four novel objects placed around the perimeter. The test mouse is allowed to freely explore the arena and the order in which the mouse investigates the novel objects is recorded. From these data, patterned sequences of exploration can be identified, as can the most preferred object for each mouse. The representative data shared here and past results using the novel object exploration assay illustrate that inbred mouse strains do demonstrate different behavior in this assay and that strains with elevated lower order RRBs also show elevated patterned behavior. As such, the novel object exploration assay appears to possess good face validity for higher order RRBs in humans and may be a valuable assay for future studies investigating novel therapeutics for ASD.

  6. An efficient higher-order PML in WLP-FDTD method for time reversed wave simulation

    Science.gov (United States)

    Wei, Xiao-Kun; Shao, Wei; Ou, Haiyan; Wang, Bing-Zhong

    2016-09-01

    Derived from a stretched coordinate formulation, a higher-order complex frequency shifted (CFS) perfectly matched layer (PML) is proposed for the unconditionally stable finite-difference time-domain (FDTD) method based on weighted Laguerre polynomials (WLPs). The higher-order PML is implemented with an auxiliary differential equation (ADE) approach. In order to further improve absorbing performance, the parameter values of stretching functions in the higher-order PML are optimized by the multi-objective genetic algorithm (MOGA). The optimal solutions can be chosen from the Pareto front for trading-off between two independent objectives. It is shown in a numerical test that the higher-order PML is efficient in terms of attenuating propagating waves and reducing late time reflections. Moreover, the higher-order PML can be placed very close to the wall when analyzing the channel characteristics of time reversal (TR) waves in a multipath indoor environment. Numerical examples of TR wave propagation demonstrate the availability of the proposed method.

  7. Proper orthogonal decomposition-based spectral higher-order stochastic estimation

    Energy Technology Data Exchange (ETDEWEB)

    Baars, Woutijn J., E-mail: wbaars@unimelb.edu.au [Department of Mechanical Engineering, The University of Melbourne, Melbourne, Victoria 3010 (Australia); Tinney, Charles E. [Center for Aeromechanics Research, The University of Texas at Austin, Austin, Texas 78712 (United States)

    2014-05-15

    A unique routine, capable of identifying both linear and higher-order coherence in multiple-input/output systems, is presented. The technique combines two well-established methods: Proper Orthogonal Decomposition (POD) and Higher-Order Spectra Analysis. The latter of these is based on known methods for characterizing nonlinear systems by way of Volterra series. In that, both linear and higher-order kernels are formed to quantify the spectral (nonlinear) transfer of energy between the system's input and output. This reduces essentially to spectral Linear Stochastic Estimation when only first-order terms are considered, and is therefore presented in the context of stochastic estimation as spectral Higher-Order Stochastic Estimation (HOSE). The trade-off to seeking higher-order transfer kernels is that the increased complexity restricts the analysis to single-input/output systems. Low-dimensional (POD-based) analysis techniques are inserted to alleviate this void as POD coefficients represent the dynamics of the spatial structures (modes) of a multi-degree-of-freedom system. The mathematical framework behind this POD-based HOSE method is first described. The method is then tested in the context of jet aeroacoustics by modeling acoustically efficient large-scale instabilities as combinations of wave packets. The growth, saturation, and decay of these spatially convecting wave packets are shown to couple both linearly and nonlinearly in the near-field to produce waveforms that propagate acoustically to the far-field for different frequency combinations.

  8. Simplification of the Flux Function for a Higher-order Gas-kinetic Evolution Model

    CERN Document Server

    Zhou, Guangzhao; Liu, Feng

    2016-01-01

    The higher-order gas-kinetic scheme for solving the Navier-Stokes equations has been studied in recent years. In addition to the use of higher-order reconstruction techniques, many terms are used in the Taylor expansion of the gas distribution functions. Therefore, a large number of coefficients need to be determined in the calculation of the time evolution of the gas distribution function at cell interfaces. As a consequence, the higher-order flux function takes much more computational time than that of a second-order gas-kinetic scheme. This paper aims to simplify the evolution model by two steps. Firstly, the coefficients related to the higher-order spatial and temporal derivatives of a distribution function are redefined to reduce the computational cost. Secondly, based on the physical analysis, some terms can be removed without loss of accuracy. Through the simplifications, the computational efficiency of the higher-order scheme is increased significantly. In addition, a self-adaptive numerical viscosity...

  9. A Stable Higher Order Space-Time Galerkin Scheme for Time Domain Integral Equations

    CERN Document Server

    Pray, A J; Nair, N V; Cools, K; Bağcı, H; Shanker, B

    2014-01-01

    Stability of time domain integral equation (TDIE) solvers has remained an elusive goal for many years. Advancement of this research has largely progressed on four fronts: (1) Exact integration, (2) Lubich quadrature, (3) smooth temporal basis functions, and (4) Space-time separation of convolutions with the retarded potential. The latter method was explored in [Pray et al. IEEE TAP 2012]. This method's efficacy in stabilizing solutions to the time domain electric field integral equation (TD-EFIE) was demonstrated on first order surface descriptions (flat elements) in tandem with 0th order functions as the temporal basis. In this work, we develop the methodology necessary to extend to higher order surface descriptions as well as to enable its use with higher order temporal basis functions. These higher order temporal basis functions are used in a Galerkin framework. A number of results that demonstrate convergence, stability, and applicability are presented.

  10. A finite deformation theory of higher-order gradient crystal plasticity

    DEFF Research Database (Denmark)

    Kuroda, Mitsutoshi; Tvergaard, Viggo

    2008-01-01

    crystal plasticity that is based on an assumption of the existence of higher-order stresses. Furthermore, a boundary-value problem for simple shear of a constrained thin strip is studied numerically, and some characteristic features of finite deformation are demonstrated through a comparison to a solution......For higher-order gradient crystal plasticity, a finite deformation formulation is presented. The theory does not deviate much from the conventional crystal plasticity theory. Only a back stress effect and additional differential equations for evolution of the geometrically necessary dislocation...... (GND) densities supplement the conventional theory within a non-work-conjugate framework in which there is no need to introduce higher-order microscopic stresses that would be work-conjugate to slip rate gradients. We discuss its connection to a work-conjugate type of finite deformation gradient...

  11. Regularity properties of fiber derivatives associated with higher-order mechanical systems

    Science.gov (United States)

    Colombo, Leonardo; Prieto-Martínez, Pedro Daniel

    2016-08-01

    The aim of this work is to study fiber derivatives associated to Lagrangian and Hamiltonian functions describing the dynamics of a higher-order autonomous dynamical system. More precisely, given a function in T∗T(k-1)Q, we find necessary and sufficient conditions for such a function to describe the dynamics of a kth-order autonomous dynamical system, thus being a kth-order Hamiltonian function. Then, we give a suitable definition of (hyper)regularity for these higher-order Hamiltonian functions in terms of their fiber derivative. In addition, we also study an alternative characterization of the dynamics in Lagrangian submanifolds in terms of the solutions of the higher-order Euler-Lagrange equations.

  12. Higher-order-statistics-based radial basis function networks for signal enhancement.

    Science.gov (United States)

    Lin, Bor-Shyh; Lin, Bor-Shing; Chong, Fok-Ching; Lai, Feipei

    2007-05-01

    In this paper, a higher-order-statistics (HOS)-based radial basis function (RBF) network for signal enhancement is introduced. In the proposed scheme, higher order cumulants of the reference signal were used as the input of HOS-based RBF. An HOS-based supervised learning algorithm, with mean square error obtained from higher order cumulants of the desired input and the system output as the learning criterion, was used to adapt weights. The motivation is that the HOS can effectively suppress Gaussian and symmetrically distributed non-Gaussian noise. The influence of a Gaussian noise on the input of HOS-based RBF and the HOS-based learning algorithm can be mitigated. Simulated results indicate that HOS-based RBF can provide better performance for signal enhancement under different noise levels, and its performance is insensitive to the selection of learning rates. Moreover, the efficiency of HOS-based RBF under the nonstationary Gaussian noise is stable.

  13. Higher order asymptotic fields for mode Ⅰ crack in functionally gradient material

    Institute of Scientific and Technical Information of China (English)

    DAI Yao; YAN Xiu-fa

    2005-01-01

    Higher order stress fields for a mode Ⅰ crack perpendicular to the direction of property variation in a functionally gradient material(FGM), which has an exponential variation of elastic modulus along the gradient direction, were obtained through an asymptotic analysis. The Poisson's ratio of the FGMs was assumed to be constant throughout the analysis. The first five terms in the asymptotic expansions of crack tip stress fields were derived to bring out the influence of nonhomogeneity on the structure of the stress field explicitly. The analysis reveals that only the higher order terms in the expansion are influenced by the material nonhomogeneity. Moreover, it can be seen from expressions of higher order stress fields that at least three terms must be considered in the case of FGMs in order to explicitly account for the nonhomogeneity effects on the structure of crack tip stress fields.

  14. Investigating higher order modes effects on thermionic RF gun transverse emittance

    Science.gov (United States)

    Rajabi, A.; Shokri, B.; Feghhi, S. A. H.

    2017-02-01

    As the excitation of higher order modes in high gradient accelerating cavities of the RF gun negatively influences electron beam quality, in the present work a theory is obtained based on generalizing Panofsky-Wenzel theorem to study the effect of transverse magnetic modes on transverse emittance growth of the RF gun. Based on this theory, the impact of higher order modes on transverse momentum is investigated. Based on analysis and simulation results, it is shown that different RF modes result in divergence or convergence effects on beam transverse dynamics. The presence of dipole and quadrupole modes can enhance the transverse emittance by 320 % and 450 % , respectively. The compound effect of the presence of two higher order modes results in 470 % transverse emittance growth.

  15. Isomorphisms of types in the presence of higher-order references

    CERN Document Server

    Clairambault, Pierre

    2011-01-01

    We investigate the problem of type isomorphisms in a programming language with higher-order references. We first recall the game-theoretic model of higher-order references by Abramsky, Honda and McCusker. Solving an open problem by Laurent, we show that two finitely branching arenas are isomorphic if and only if they are geometrically the same, up to renaming of moves (Laurent's forest isomorphism). We deduce from this an equational theory characterizing isomorphisms of types in a finitary language with higher order references. We show however that Laurent's conjecture does not hold on infinitely branching arenas, yielding a non-trivial type isomorphism in the extension of this language with natural numbers.

  16. On the selection of tuning methodology of FOPID controllers for the control of higher order processes.

    Science.gov (United States)

    Das, Saptarshi; Saha, Suman; Das, Shantanu; Gupta, Amitava

    2011-07-01

    In this paper, a comparative study is done on the time and frequency domain tuning strategies for fractional order (FO) PID controllers to handle higher order processes. A new fractional order template for reduced parameter modelling of stable minimum/non-minimum phase higher order processes is introduced and its advantage in frequency domain tuning of FOPID controllers is also presented. The time domain optimal tuning of FOPID controllers have also been carried out to handle these higher order processes by performing optimization with various integral performance indices. The paper highlights on the practical control system implementation issues like flexibility of online autotuning, reduced control signal and actuator size, capability of measurement noise filtration, load disturbance suppression, robustness against parameter uncertainties etc. in light of the above tuning methodologies.

  17. Higher-Order Markov Tag-Topic Models for Tagged Documents and Images

    CERN Document Server

    Zeng, Jia; Cheung, William K; Li, Chun-Hung

    2011-01-01

    This paper studies the topic modeling problem of tagged documents and images. Higher-order relations among tagged documents and images are major and ubiquitous characteristics, and play positive roles in extracting reliable and interpretable topics. In this paper, we propose the tag-topic models (TTM) to depict such higher-order topic structural dependencies within the Markov random field (MRF) framework. First, we use the novel factor graph representation of latent Dirichlet allocation (LDA)-based topic models from the MRF perspective, and present an efficient loopy belief propagation (BP) algorithm for approximate inference and parameter estimation. Second, we propose the factor hypergraph representation of TTM, and focus on both pairwise and higher-order relation modeling among tagged documents and images. Efficient loopy BP algorithm is developed to learn TTM, which encourages the topic labeling smoothness among tagged documents and images. Extensive experimental results confirm the incorporation of highe...

  18. Higher-order adaptive finite-element methods for Kohn-Sham density functional theory

    CERN Document Server

    Motamarri, Phani; Leiter, Kenneth; Knap, Jaroslaw; Gavini, Vikram

    2012-01-01

    We present an efficient computational approach to perform real-space electronic structure calculations using an adaptive higher-order finite-element discretization of Kohn-Sham density-functional theory (DFT).To this end, we develop an \\emph{a priori} mesh adaption technique to construct a close to optimal finite-element discretization of the problem. We further propose an efficient solution strategy for solving the discrete eigenvalue problem by using spectral finite-elements in conjunction with Gauss-Lobatto quadrature, and a Chebyshev acceleration technique for computing the occupied eigenspace. Using the proposed solution procedure, we investigate the computational efficiency afforded by higher-order finite-element discretizations of the Kohn-Sham DFT problem. Our studies suggest that staggering computational savings---of the order of $1000-$fold---can be realized, for both all-electron and pseudopotential calculations, by using higher-order finite-element discretizations. On all the benchmark systems stu...

  19. Higher-order effects on self-similar parabolic pulse in the microstructured fibre amplifier

    Institute of Scientific and Technical Information of China (English)

    Liu Wei-Ci; Xu Wen-Cheng; Feng Jie; Chen Wei-Cheng; Li Shu-Xian; Lin Song-Hao

    2008-01-01

    By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical results indicate that the higher-order effects can badly distort self-similar parabolic pulse shape and optical spectrum, and at the same time the peak shift and oscillation appear, while the pulse still reveals highly linear chirp but grows into asymmetry. The influence of different higher-order effects on self-similar parabolic pulse propagation has been analysed. It shows thatthe self-steepening plays a more important role. We can manipulate the geometrical parameters of the microstructured fibre amplifier to gain a suitable dispersion and nonlinearity coefficient which will keep high-quality self-similar parabolic pulse propagation. These results are significant for the further study of self-similar parabolic pulse propagation.

  20. The Analysis of Thin Wires Using Higher-Order Elements and Basis Functions

    Energy Technology Data Exchange (ETDEWEB)

    Champagne, N J; Wilton, D R; Rockway, J W

    2006-01-23

    Thin wire analysis was applied to curved wire segments in [1], but a special procedure was needed to evaluate the self and near-self terms. The procedure involved associating the singular behavior with a straight segment tangent to the curved source segment, permitting use of algorithms for straight wires. Recently, a procedure that avoids the singularity extraction for straight wires was presented in [2-4]. In this paper, the approach in [4] is applied to curved (or higher-order) wires using a procedure similar to that used in [1] for singularity extraction. Here, the straight tangent segment is used to determine the quadrature rules to be used on the curved segment. The result is a formulation that allows for a general mixture of higher-order basis functions [5] and higher-order wire segments.

  1. Design and Application of Strategies/Tactics in Higher Order Logics

    Science.gov (United States)

    Archer, Myla (Editor); diVito, Ben (Editor); Munoz, Cesar (Editor)

    2003-01-01

    This Proceedings includes both a paper from the implementors of PVS providing guidance for PVS strategy writers and a tutorial on PVS strategy writing distilled from the experience of three PVS users who have written extensive sets of PVS user strategies. Following these are three full papers from the higher-order logic theorem proving community that discuss PVS strategies to enhance arithmetic and other interactive reasoning in PVS; implementing first-order tactics in higher-order provers; and a proposed technique for specifying small step semantics that can be used in multiple higher order logic theorem provers, with illustrations from both Coq and PVS. The Proceedings concludes with three position papers for a panel session that discuss three settings in which development of PVS strategies is worth while.

  2. Efficient Query Rewrite for Structured Web Queries

    CERN Document Server

    Gollapudi, Sreenivas; Ntoulas, Alexandros; Paparizos, Stelios

    2011-01-01

    Web search engines and specialized online verticals are increasingly incorporating results from structured data sources to answer semantically rich user queries. For example, the query \\WebQuery{Samsung 50 inch led tv} can be answered using information from a table of television data. However, the users are not domain experts and quite often enter values that do not match precisely the underlying data. Samsung makes 46- or 55- inch led tvs, but not 50-inch ones. So a literal execution of the above mentioned query will return zero results. For optimal user experience, a search engine would prefer to return at least a minimum number of results as close to the original query as possible. Furthermore, due to typical fast retrieval speeds in web-search, a search engine query execution is time-bound. In this paper, we address these challenges by proposing algorithms that rewrite the user query in a principled manner, surfacing at least the required number of results while satisfying the low-latency constraint. We f...

  3. Higher Order Modeling in Hybrid Approaches to the Computation of Electromagnetic Fields

    Science.gov (United States)

    Wilton, Donald R.; Fink, Patrick W.; Graglia, Roberto D.

    2000-01-01

    Higher order geometry representations and interpolatory basis functions for computational electromagnetics are reviewed. Two types of vector-valued basis functions are described: curl-conforming bases, used primarily in finite element solutions, and divergence-conforming bases used primarily in integral equation formulations. Both sets satisfy Nedelec constraints, which optimally reduce the number of degrees of freedom required for a given order. Results are presented illustrating the improved accuracy and convergence properties of higher order representations for hybrid integral equation and finite element methods.

  4. In-medium QCD sum rules for D mesons: A projection method for higher order contributions

    CERN Document Server

    Buchheim, Thomas; Kampfer, Burkhard

    2014-01-01

    D mesons serve as excellent probes of hot and/or dense strongly interacting matter. They can provide insight into the restoration of chiral symmetry. The chiral condensate as well as other chirally odd condensates, such as certain four-quark condensates, are linked to order parameters of spontaneous chiral symmetry breaking. Thus, the evaluation of these higher order condensate contributions in the framework of QCD sum rules is of high interest. We present a general method for projecting Lorentz indices of ground state expectation values providing a crucial step towards a comprehensive calculation of higher order corrections to the operator product expansion of hadrons, especially D mesons, in a strongly interacting medium.

  5. Objective Reduction Solutions to Higher-Order Boussinesq System in (2+1)-Dimensions

    Institute of Scientific and Technical Information of China (English)

    HU Ya-Hong; ZHENG Chun-Long

    2009-01-01

    With the help of an objective reduction approach (ORA), abundant exact solutions of (2+1)-dimensional higher-order Boussinesq system (including some hyperboloid function solutions, trigonometric function solutions, and a rational function solution) are obtained. It is shown that some novel soliton structures, like single linearity soliton structure, breath soliton structure, single linearity y-periodic solitary wave structure, libration dromion structure, and kink-like multisoliton structure with actual physical meaning exist in the (2+1)-dimensional higher-order Bonssinesq system.

  6. Multiple higher-order stop gaps in infrared polymer photonic crystals.

    Science.gov (United States)

    Straub, M; Ventura, M; Gu, M

    2003-07-25

    Engineering of stop gaps between higher photonic bands provides an alternative to miniaturization of photonic crystals. Femtosecond laser microfabrication of highly correlated void channel polymer microstructures results in photonic crystals with large stop gaps and a multitude of higher-order gaps in the mid- and near-infrared spectral regions. The gap wavelengths obey Bragg's law. Consistent with theory, varying the woodpile structure unit cell allows for tuning the number of higher-order gaps, and transitions from mere resonant Bragg scattering to stop band total reflection are observed.

  7. RCS Computation by Parallel MoM Using Higher-Order Basis Functions

    Directory of Open Access Journals (Sweden)

    Ying Yan

    2012-01-01

    Full Text Available A Message-Passing Interface (MPI parallel implementation of an integral equation solver that uses the Method of Moments (MoM with higher-order basis functions has been proposed to compute the Radar Cross-Section (RCS of various targets. The block-partitioned scheme for the large dense MoM matrix is designed to achieve excellent load balance and high parallel efficiency. Some numerical results demonstrate that higher-order basis in this parallelized scheme is more efficient than the conventional RWG method and able to efficiently analyze RCS of various electrically large platforms.

  8. Wave train generation of solitons in systems with higher-order nonlinearities.

    Science.gov (United States)

    Mohamadou, Alidou; LatchioTiofack, C G; Kofané, Timoléon C

    2010-07-01

    Considering the higher-order nonlinearities in a material can significantly change its behavior. We suggest the extended nonlinear Schrödinger equation to describe the propagation of ultrashort optical pulses through a dispersive medium with higher-order nonlinearities. Soliton trains are generated through the modulational instability and we point out the influence of the septic nonlinearity in the modulational instability gain. Experimental values are used for the numerical simulations and the input plane wave leads to the development of pulse trains, depending upon the sign of the septic nonlinearity.

  9. Self-Deflection of Dark Screening Spatial Solitons Based on Higher-Order Space Charge Field

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guang-Yong; LIU Jin-Song; LIU Shi-Xiong; WANG Cheng; ZHANG Hui-Lan

    2007-01-01

    The effects of higher-order space charge field on the self-deflection of dark screening spatial solitons in biased photorefractive crystals are numerically investigated under steady-state conditions. The expression for an induced space-charge electric field including higher-order space-charge field terms is obtained. Numerical results indicate that dark solitons possess a self-deflection process during propagation, and the solitons always bend in the direction of the c axis of the crystal The self-deflection of dark solitons can experience considerable increase especially in the regime of high bias field strengths.

  10. Optical diagnosis of cervical cancer by higher order spectra and boosting

    Science.gov (United States)

    Pratiher, Sawon; Mukhopadhyay, Sabyasachi; Barman, Ritwik; Pratiher, Souvik; Pradhan, Asima; Ghosh, Nirmalya; Panigrahi, Prasanta K.

    2017-03-01

    In this contribution, we report the application of higher order statistical moments using decision tree and ensemble based learning methodology for the development of diagnostic algorithms for optical diagnosis of cancer. The classification results were compared to those obtained with an independent feature extractors like linear discriminant analysis (LDA). The performance and efficacy of these methodology using higher order statistics as a classifier using boosting has higher specificity and sensitivity while being much faster as compared to other time-frequency domain based methods.

  11. Improvement on polynomial Wigner-Ville distribution for detecting higher-order polynomial phase signal

    Institute of Scientific and Technical Information of China (English)

    Tan Xiaogang; Wei Ping; Li Liping

    2009-01-01

    To detect higher order polynomial phase signals (HOPPSs), the smoothed-pseudo polynomial Wigner-Ville distribution (SP-PWVD), an improved version of the polynomial Wigner-Ville distribution (PWVD), is pre-sented using a separable kernel. By adjusting the lengths of the functions in the kernel, the balance between resolution retaining and interference suppressing can be adjusted conveniently. The proposed method with merits of interference terms reduction and noise suppression can provide time frequency representation of better readability and more accurate instantaneous frequency (IF) estimation with higher order SP-PWVD. The performance of the SP-PWVD is verified by computer simulations.

  12. Linearization of a warped $f(R)$ theory in the higher-order frame

    CERN Document Server

    Zhong, Yuan

    2016-01-01

    The linearization of a type of $f(R)$ gravity is studied directly in the higher-order frame for an arbitrary five-dimensional warped space-time background. The quadratic actions of the normal modes of the scalar, vector and tensor perturbations are derived, and compared to those obtained in the Einstein frame. We find that the corresponding quadratic actions are equivalent. From the point of view of the higher-order frame, the best gauge choice is the curvature gauge, under which the linear perturbation of the scalar curvature is zero, and all the perturbation equations reduce to second order.

  13. Dynamic control of higher-order modes in hollow-core photonic crystal fibers.

    Science.gov (United States)

    Euser, T G; Whyte, G; Scharrer, M; Chen, J S Y; Abdolvand, A; Nold, J; Kaminski, C F; Russell, P St J

    2008-10-27

    We present a versatile method for selective mode coupling into higher-order modes of photonic crystal fibers, using holograms electronically generated by a spatial light modulator. The method enables non-mechanical and completely repeatable changes in the coupling conditions. We have excited higher order modes up to LP(31) in hollow-core photonic crystal fibers. The reproducibility of the coupling allows direct comparison of the losses of different guided modes in both hollow-core bandgap and kagome-lattice photonic crystal fibers. Our results are also relevant to applications in which the intensity distribution of the light inside the fiber is important, such as particle- or atom-guidance.

  14. A TWO-SCALE HIGHER-ORDER FINITE ELEMENT DISCRETIZATION FOR SCHRODINGER EQUATION

    Institute of Scientific and Technical Information of China (English)

    Huajie Chen; Fang Liu; Aihui Zhou

    2009-01-01

    In this paper,a two-scale higher-order finite element discretization scheme is proposed and analyzed for a Schr(o)dinger equation on tensor product domains.With the scheme,the solution of the eigenvalue problem on a fine grid can be reduced to an eigenvalue problem on a much coarser grid together with some eigenvalue problems on partially fine grids.It is shown theoretically and numerically that the proposed two-scale higher-order scheme not only significantly reduces the number of degrees of freedom but also produces very accurate approximations.

  15. A higher-order nonlocal elasticity and strain gradient theory and its applications in wave propagation

    Science.gov (United States)

    Lim, C. W.; Zhang, G.; Reddy, J. N.

    2015-05-01

    In recent years there have been many papers that considered the effects of material length scales in the study of mechanics of solids at micro- and/or nano-scales. There are a number of approaches and, among them, one set of papers deals with Eringen's differential nonlocal model and another deals with the strain gradient theories. The modified couple stress theory, which also accounts for a material length scale, is a form of a strain gradient theory. The large body of literature that has come into existence in the last several years has created significant confusion among researchers about the length scales that these various theories contain. The present paper has the objective of establishing the fact that the length scales present in nonlocal elasticity and strain gradient theory describe two entirely different physical characteristics of materials and structures at nanoscale. By using two principle kernel functions, the paper further presents a theory with application examples which relates the classical nonlocal elasticity and strain gradient theory and it results in a higher-order nonlocal strain gradient theory. In this theory, a higher-order nonlocal strain gradient elasticity system which considers higher-order stress gradients and strain gradient nonlocality is proposed. It is based on the nonlocal effects of the strain field and first gradient strain field. This theory intends to generalize the classical nonlocal elasticity theory by introducing a higher-order strain tensor with nonlocality into the stored energy function. The theory is distinctive because the classical nonlocal stress theory does not include nonlocality of higher-order stresses while the common strain gradient theory only considers local higher-order strain gradients without nonlocal effects in a global sense. By establishing the constitutive relation within the thermodynamic framework, the governing equations of equilibrium and all boundary conditions are derived via the variational

  16. Unifying refinement and hoare-style reasoning in a logic for higher-order concurrency

    DEFF Research Database (Denmark)

    Turon, Aaron; Dreyer, Derek; Birkedal, Lars

    2013-01-01

    Modular programming and modular verification go hand in hand, but most existing logics for concurrency ignore two crucial forms of modularity: *higher-order functions*, which are essential for building reusable components, and *granularity abstraction*, a key technique for hiding the intricacies...... of fine-grained concurrent data structures from the clients of those data structures. In this paper, we present CaReSL, the first logic to support the use of granularity abstraction for modular verification of higher-order concurrent programs. After motivating the features of CaReSL through a variety...

  17. Generating Functions of the Unified Representation of the Bernoulli, Euler and Genocchi Polynomials of Higher Order

    Science.gov (United States)

    Ozden, Hacer

    2011-09-01

    The aim of this paper is to define the generating functions of the Bernoulli, Euler and Genocchi polynomials of higher order. By using these generating functions, we derive some identities and relations on these polynomials. Our results generalize the classical Bernoulli, Euler, Genocchi polynomials and also Apostol-Bernoulli, Apostol-Euler and Apostol-Genocchi polynomials.

  18. Higher-order linear matrix descriptor differential equations of Apostol-Kolodner type

    Directory of Open Access Journals (Sweden)

    2009-02-01

    Full Text Available In this article, we study a class of linear rectangular matrix descriptor differential equations of higher-order whose coefficients are square constant matrices. Using the Weierstrass canonical form, the analytical formulas for the solution of this general class is analytically derived, for consistent and non-consistent initial conditions.

  19. The advantage of higher-order theory of mind in the game of limited bidding

    NARCIS (Netherlands)

    De Weerd, H.; Verheij, B.; van Eijck, J.; Verbrugge, L. C.

    2011-01-01

    Higher-order theory of mind is the ability to recursively model mental states of other agents. It is known that adults in general can reason adequately at the second order (covering attributions like "Alice knows that Bob knows that she wrote a novel under pseudonym"), but there are cognitive limits

  20. New explicit global asymptotic stability criteria for higher order difference equations

    Science.gov (United States)

    El-Morshedy, Hassan A.

    2007-12-01

    New explicit sufficient conditions for the asymptotic stability of the zero solution of higher order difference equations are obtained. These criteria can be applied to autonomous and nonautonomous equations. The celebrated Clark asymptotic stability criterion is improved. Also, applications to models from mathematical biology and macroeconomics are given.

  1. Multi-domain, higher order level set scheme for 3D image segmentation on the GPU

    DEFF Research Database (Denmark)

    Sharma, Ojaswa; Zhang, Qin; Anton, François;

    2010-01-01

    Level set method based segmentation provides an efficient tool for topological and geometrical shape handling. Conventional level set surfaces are only $C^0$ continuous since the level set evolution involves linear interpolation to compute derivatives. Bajaj et al. present a higher order method t...

  2. Higher order non-local (n-1,1) conjugate type boundary value problems

    Science.gov (United States)

    Webb, J. R. L.

    2009-05-01

    We show how some recent work of Webb and Infante, which gave a unified method of tackling many nonlocal boundary value problems, can be applied to some higher order boundary value problems with more general nonlocal boundary conditions than previously studied. This improves some recent work on problems with conjugate type boundary conditions.

  3. Computer Game Development: An Instructional Strategy to Promote Higher Order Thinking Skills

    Science.gov (United States)

    Prayaga, Lakshmi; Coffey, John W.

    2008-01-01

    Several studies have demonstrated that games have been effectively used as an instructional strategy to motivate and engage students. This paper presents the use of the process of game development as an instructional strategy to promote higher order thinking skills. An analysis of the various aspects of game development including graphics,…

  4. Factors Affecting Higher Order Thinking Skills of Students: A Meta-Analytic Structural Equation Modeling Study

    Science.gov (United States)

    Budsankom, Prayoonsri; Sawangboon, Tatsirin; Damrongpanit, Suntorapot; Chuensirimongkol, Jariya

    2015-01-01

    The purpose of the research is to develop and identify the validity of factors affecting higher order thinking skills (HOTS) of students. The thinking skills can be divided into three types: analytical, critical, and creative thinking. This analysis is done by applying the meta-analytic structural equation modeling (MASEM) based on a database of…

  5. Assessment choices to target higher order learning outcomes: the power of academic empowerment

    Directory of Open Access Journals (Sweden)

    Margot McNeill

    2012-09-01

    Full Text Available Assessment of higher order learning outcomes such as critical thinking, problem solving and creativity has remained a challenge for universities. While newer technologies such as social networking tools have the potential to support these intended outcomes, academics’ assessment practice is slow to change. University mission statements and unit outlines may purport the value of higher order skills; however, questions remain about how well academics are equipped to design their curriculum and particularly their assessment strategies accordingly. This paper reports on an investigation of academic practice in assessing higher order learning in their units. Despite their intentions towards higher order learning outcomes for their students, the results suggest academics may make decisions when planning their assessment tasks that inadvertently lead students on the path towards lower order outcomes. Among the themes to emerge from the study is the importance of academics’ confidence and their attitudes towards the role of assessment in learning and how these perspectives, along with the types of learning outcomes they intend for their students, can influence their task design.

  6. Controlled generation of higher-order Poincaré sphere beams from a laser

    CSIR Research Space (South Africa)

    Naidoo, Darryl

    2016-03-01

    Full Text Available . 10: 327-332 Controlled generation of higher-order Poincaré sphere beams from a laser Naidoo D Roux FS Dudley A Litvin I Piccirillo B Marrucci L Forbes A ABSTRACT: The angular momentum of light can be described by positions on a...

  7. Problem-Based Learning and Use of Higher-Order Thinking by Emergency Medical Technicians

    Science.gov (United States)

    Rosenberger, Paul

    2013-01-01

    Emergency Medical Technicians (EMTs) often handle chaotic life-and-death situations that require higher-order thinking skills. Improving the pass rate of EMT students depends on many factors, including the use of proven and effective teaching methods. Results from recent research about effective teaching have suggested that the instructional…

  8. Formalizing Higher-order Mobile Embedded Business Processes with Binding Bigraphs

    DEFF Research Database (Denmark)

    Bundgaard, Mikkel; Glenstrup, Arne John; Hildebrandt, Thomas

    2008-01-01

    We propose and formalize HomeBPEL, a higher-order WSBPEL-like business process execution language where processes are firstclass values that can be stored in variables, passed as messages, and activated as embedded sub-instances. A sub-instance is similar to a WSBPEL scope, except that it can...

  9. Efficient nonlinear generation of high power, higher order, ultrafast "perfect" vortices in green

    CERN Document Server

    Chaitanya, N Apurv; Samanta, G K

    2016-01-01

    We report on efficient nonlinear generation of ultrafast, higher order "perfect" vortices at the green wavelength. Based on Fourier transformation of the higher order Bessel-Gauss beam generated through the combination of spiral phase plate and axicon we have transformed the Gaussian beam of the ultrafast Yb-fiber laser at 1060 nm into perfect vortices of power 4.4 W and order up to 6. Using single-pass second harmonic generation (SHG) of such vortices in 5-mm long chirped MgO-doped, periodically poled congruent LiNbO$_3$ crystal we have generated perfect vortices at green wavelength with output power of 1.2 W and vortex order up to 12 at single-pass conversion efficiency of 27% independent of its order. This is the highest single-pass SHG efficiency of any optical beams other than Gaussian beams. Unlike the disintegration of higher order vortices in birefringent crystals, here, the use of quasi-phase matching process enables generation of high quality vortices even at higher orders. The green perfect vortice...

  10. On the periodic mild solutions to complete higher order differential equations on Banach spaces

    Directory of Open Access Journals (Sweden)

    Lan Nguyen

    2011-08-01

    Full Text Available For the complete higher order differential equation u(n(t=∑k=0n-1Aku(k(t+f(t, 0 ≤ t ≤ T, on a Banach space E, we give necessary and sufficient conditions for the periodicity of mild solutions. The results, which are proved in a simple manner, generalize some well-known ones.

  11. Blind equalization of underwater acoustic channels using implicit higher-order statistics

    NARCIS (Netherlands)

    Blom, Koen C.H.; Dol, Henry S.; Kokkeler, André B.J.; Smit, Gerard J.M.

    2016-01-01

    In order to reduce the length of transmission time slots and energy consumption of underwater modems, this work focuses on equalization without the need for training sequences. This type of equalization is known as blind equalization. A blind equalizer cascade based on higher-order statistics is pre

  12. On Higher-order Corrections to Gyrokinetic Vlasov-Poisson Equations in the Long Wavelength Limit

    Energy Technology Data Exchange (ETDEWEB)

    W.W. Lee and R.A. Kolesnikov

    2009-02-17

    In this paper, we present a simple iterative procedure for obtaining the higher order E x B and dE/dt (polarization) drifts associated with the gyrokinetic Vlasov-Poisson equations in the long wavelength limit of k⊥ρi ~ o(ε) and k⊥L ~ o(1), where ρi is the ion gyroradius, L is the scale length of the background inhomogeneity and ε is a smallness parameter. It can be shown that these new higher order k⊥ρi terms, which are also related to the higher order perturbations of the electrostatic potential Φ, should have negligible effects on turbulent and neoclassical transport in tokamaks, regardless of the form of the background distribution and the amplitude of the perturbation. To address further the issue of a non-Maxwellian plasma, higher order finite Larmor radius terms in the gyrokinetic Poisson's equation have been studied and shown to be unimportant as well. On the other hand, the terms of o(k2⊥ρi2) ~ o(ε) and k⊥L ~ o(1) can indeed have impact on microturbulence, especially in the linear stage, such as those arising from the difference between the guiding center and the gyrocenter densities due to the presence of the background gradients. These results will be compared with a recent study questioning the validity of the commonly used gyrokinetic equations for long time simulations.

  13. The grounding of higher order concepts in action and language: a cognitive robotics model.

    Science.gov (United States)

    Stramandinoli, Francesca; Marocco, Davide; Cangelosi, Angelo

    2012-08-01

    In this paper we present a neuro-robotic model that uses artificial neural networks for investigating the relations between the development of symbol manipulation capabilities and of sensorimotor knowledge in the humanoid robot iCub. We describe a cognitive robotics model in which the linguistic input provided by the experimenter guides the autonomous organization of the robot's knowledge. In this model, sequences of linguistic inputs lead to the development of higher-order concepts grounded on basic concepts and actions. In particular, we show that higher-order symbolic representations can be indirectly grounded in action primitives directly grounded in sensorimotor experiences. The use of recurrent neural network also permits the learning of higher-order concepts based on temporal sequences of action primitives. Hence, the meaning of a higher-order concept is obtained through the combination of basic sensorimotor knowledge. We argue that such a hierarchical organization of concepts can be a possible account for the acquisition of abstract words in cognitive robots. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Optical rogue waves in the generalized inhomogeneous higher-order nonlinear Schrodinger equation with modulating coefficients

    CERN Document Server

    Yan, Zhenya

    2013-01-01

    The higher-order dispersive and nonlinear effects (alias {\\it the perturbation terms}) like the third-order dispersion, the self-steepening, and the self-frequency shift play important roles in the study of the ultra-short optical pulse propagation. We consider optical rogue wave solutions and interactions for the generalized higher-order nonlinear Schr\\"odinger (NLS) equation with space- and time-modulated parameters. A proper transformation is presented to reduce the generalized higher-order NLS equation to the integrable Hirota equation with constant coefficients. This transformation allows us to relate certain class of exact solutions of the generalized higher-order NLS equation to the variety of solutions of the integrable Hirota equation. In particular, we illustrate the approach in terms of two lowest-order rational solutions of the Hirota equation as seeding functions to generate rogue wave solutions localized in time that have complicated evolution in space with or without the differential gain or lo...

  15. Reproduction of nearby sound sources using higher-order ambisonics with practical loudspeaker arrays

    DEFF Research Database (Denmark)

    Favrot, Sylvain Emmanuel; Buchholz, Jörg

    2012-01-01

    In order to reproduce nearby sound sources with distant loudspeakers to a single listener, the near field compensated (NFC) method for higher-order Ambisonics (HOA) has been previously proposed. In practical realization, this method requires the use of regularization functions. This study analyze...

  16. Fluid-structure interaction simulations: efficient higher order time integration of partitioned systems

    NARCIS (Netherlands)

    van Zuijlen, A.H.

    2006-01-01

    The simulation of fluid-structure interaction can be a very time-consuming task due to the large amount of time steps that need to be taken in order to obtain an accurate solution. To reduce computing times a higher order time integration algorithm is applied. Based on a mixed combination of implici

  17. Compound waves in a higher order nonlinear model of thermoviscous fluids

    DEFF Research Database (Denmark)

    Rønne Rasmussen, Anders; Sørensen, Mads Peter; Gaididei, Yuri B.

    2016-01-01

    A generalized traveling wave ansatz is used to investigate compound shock waves in a higher order nonlinear model of a thermoviscous fluid. The fluid velocity potential is written as a traveling wave plus a linear function of space and time. The latter offers the possibility of predicting...

  18. Impedance Eduction in Large Ducts Containing Higher-Order Modes and Grazing Flow

    Science.gov (United States)

    Watson, Willie R.; Jones, Michael G.

    2017-01-01

    Impedance eduction test data are acquired in ducts with small and large cross-sectional areas at the NASA Langley Research Center. An improved data acquisition system in the large duct has resulted in increased control of the acoustic energy in source modes and more accurate resolution of higher-order duct modes compared to previous tests. Two impedance eduction methods that take advantage of the improved data acquisition to educe the liner impedance in grazing flow are presented. One method measures the axial propagation constant of a dominant mode in the liner test section (by implementing the Kumarsean and Tufts algorithm) and educes the impedance from an exact analytical expression. The second method solves numerically the convected Helmholtz equation and minimizes an objective function to obtain the liner impedance. The two methods are tested first on data synthesized from an exact mode solution and then on measured data. Results show that when the methods are applied to data acquired in the larger duct with a dominant higher-order mode, the same impedance spectra are educed as that obtained in the small duct where only the plane wave mode propagates. This result holds for each higher-order mode in the large duct provided that the higher-order mode is sufficiently attenuated by the liner.

  19. The Higher Order Factor Structure and Gender Invariance of the Pathological Narcissism Inventory

    Science.gov (United States)

    Wright, Aidan G. C.; Lukowitsky, Mark R.; Pincus, Aaron L.; Conroy, David E.

    2010-01-01

    The Pathological Narcissism Inventory (PNI) is a recently developed multidimensional inventory for the assessment of pathological narcissism. The authors describe and report the results of two studies that investigate the higher order factor structure and gender invariance of the PNI. The results of the first study indicate that the PNI has a…

  20. Impact of ligand protonation on higher-order metal complexation kinetics in aqueous systems

    NARCIS (Netherlands)

    Town, R.M.; Leeuwen, van H.P.

    2008-01-01

    The impact of ligand protonation on the complexation kinetics of higher-order complexes is quantitatively described. The theory is formulated on the basis of the usual situation for metal complex formation in aqueous systems in which the exchange of water for the ligand in the inner coordination sph

  1. Sparse representation of higher-order functional interaction patterns in task-based FMRI data.

    Science.gov (United States)

    Zhang, Shu; Li, Xiang; Lv, Jinglei; Jiang, Xi; Zhu, Dajiang; Chen, Hanbo; Zhang, Tuo; Guo, Lei; Liu, Tianming

    2013-01-01

    Traditional task-based fMRI activation detection methods, e.g., the widely used general linear model (GLM), assume that the brain's hemodynamic responses follow the block-based or event-related stimulus paradigm. Typically, these activation detections are performed voxel-wise independently, and then are usually followed by statistical corrections. Despite remarkable successes and wide adoption of these methods, it remains largely unknown how functional brain regions interact with each other within specific networks during task performance blocks and in the baseline. In this paper, we present a novel algorithmic pipeline to statistically infer and sparsely represent higher-order functional interaction patterns within the working memory network during task performance and in the baseline. Specifically, a collection of higher-order interactions are inferred via the greedy equivalence search (GES) algorithm for both task and baseline blocks. In the next stage, an effective online dictionary learning algorithm is utilized for sparse representation of the inferred higher-order interaction patterns. Application of this framework on a working memory task-based fMRI data reveals interesting and meaningful distributions of the learned sparse dictionary atoms in task and baseline blocks. In comparison with traditional voxel-wise activation detection and recent pair-wise functional connectivity analysis, our framework offers a new methodology for representation and exploration of higher-order functional activities in the brain.

  2. Using Tests To Evaluate the Impact of Curricular Reform on Higher Order Thinking.

    Science.gov (United States)

    Davis, Alan

    The dominant issues in considering the use of tests developed outside the classroom to measure the impact of curriculum reform on higher order thinking are reviewed by a panel interviewed for this discussion. Panel members are: (1) Stuart Kahl, (2) Robert Linn, (3) Senta A. Raizen, (4) Lauren Resnick, and (5) Thomas A. Romberg. It is conceded…

  3. Expressing First-Order π-Calculus in Higher-Order Calculus of Communicating Systems

    Institute of Scientific and Technical Information of China (English)

    Xian Xu

    2009-01-01

    In the study of process calculi, encoding between different calculi is an effective way to compare the expressive power of calculi and can shed light on the essence of where the difference lies. Thomsen and Sangiorgi have worked on the higher-order calculi (higher-order Calculus of Communicating Systems (CCS) and higher-order It-calculus, respectively) and the encoding from and to first-order π-calculus. However a fully abstract encoding of first-order π-calculus with higher-order CCS is not available up-today. This is what we intend to settle in this paper. We follow the encoding strategy, first proposed by Thomsen, of translating first-order π-calculus into Plain CHOCS. We show that the encoding strategy is fully abstract with respect to early bisimilarity (first-order π-calculus) and wired bisimilarity (Plain CHOCS) (which is a bisimulation defined on wired processes only sending and receiving wires), that is the core of the encoding strategy. Moreover from the fact that the wired bisimilarity is contained by the well-established context bisimilarity, we secure the soundness of the encoding, with respect to early bisimilarity and context bisimilarity. We use index technique to get around all the technical details to reach these main results of this paper. Finally, we make some discussion on our work and suggest some future work.

  4. Geometric Hamilton-Jacobi theory for higher-order autonomous systems

    Science.gov (United States)

    Colombo, Leonardo; de León, Manuel; Prieto-Martínez, Pedro Daniel; Román-Roy, Narciso

    2014-06-01

    The geometric framework for the Hamilton-Jacobi theory is used to study this theory in the background of higher-order mechanical systems, in both the Lagrangian and Hamiltonian formalisms. Thus, we state the corresponding Hamilton-Jacobi equations in these formalisms and apply our results to analyze some particular physical examples.

  5. Controlling light in Airy and higher-order caustic photonic structures

    Science.gov (United States)

    Zannotti, Alessandro; Diebel, Falko; Rüschenbaum, Matthias; Denz, Cornelia

    2017-06-01

    Caustics form geometrically stable structures in light and are hierarchically categorized by the catastrophe theory. We embed higher-order cusp and swallowtail catastrophes in paraxial beams and investigate their dynamics. Utilizing high-intensity caustics that propagate on curved trajectories, we realize photonic caustic lattices in photosensitive media, and demonstrate waveguiding with a rich diversity of light guiding paths.

  6. On the Continuity Condition for the Higher-Order VSIE-MoM Formulation

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Jørgensen, Erik; Meincke, Peter

    2004-01-01

    examples for a finite FSS show that the explicit enforcement of the continuity condition at a metallic-dielectric interface significantly improves the solution if higher-order basis functions are defined on rather large domains with metallic edges present. This improvement manifests itself in reducing...

  7. Encouraging Higher-Order Thinking in General Chemistry by Scaffolding Student Learning Using Marzano's Taxonomy

    Science.gov (United States)

    Toledo, Santiago; Dubas, Justin M.

    2016-01-01

    An emphasis on higher-order thinking within the curriculum has been a subject of interest in the chemical and STEM literature due to its ability to promote meaningful, transferable learning in students. The systematic use of learning taxonomies could be a practical way to scaffold student learning in order to achieve this goal. This work proposes…

  8. Reexamining the Literature: The Impact of Peer Tutoring on Higher Order Learning

    Science.gov (United States)

    Morano, Stephanie; Riccomini, Paul J.

    2017-01-01

    The body of peer-tutoring intervention research targeting higher order learning (HOL) objectives for middle and high school students with disabilities is reviewed. Peer-tutoring outcomes are synthesized and studies are analyzed to examine the influence of tutoring procedures and study design features on intervention efficacy. Findings show that…

  9. Orthogonal Higher Order Structure of the WISC-IV Spanish Using Hierarchical Exploratory Factor Analytic Procedures

    Science.gov (United States)

    McGill, Ryan J.; Canivez, Gary L.

    2016-01-01

    As recommended by Carroll, the present study examined the factor structure of the Wechsler Intelligence Scale for Children-Fourth Edition Spanish (WISC-IV Spanish) normative sample using higher order exploratory factor analytic techniques not included in the WISC-IV Spanish Technical Manual. Results indicated that the WISC-IV Spanish subtests were…

  10. Stabilization of solutions to higher-order nonlinear Schrodinger equation with localized damping

    Directory of Open Access Journals (Sweden)

    Eleni Bisognin

    2007-01-01

    Full Text Available We study the stabilization of solutions to higher-order nonlinear Schrodinger equations in a bounded interval under the effect of a localized damping mechanism. We use multiplier techniques to obtain exponential decay in time of the solutions of the linear and nonlinear equations.

  11. Impact of ligand protonation on higher-order metal complexation kinetics in aqueous systems

    NARCIS (Netherlands)

    Town, R.M.; Leeuwen, van H.P.

    2008-01-01

    The impact of ligand protonation on the complexation kinetics of higher-order complexes is quantitatively described. The theory is formulated on the basis of the usual situation for metal complex formation in aqueous systems in which the exchange of water for the ligand in the inner coordination sph

  12. Exact Solutions for a Higher-Order Nonlinear Schr(o)dinger Equation in Atmospheric Dynamics

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    By giving prior assumptions on the form of the solutions, we succeed to find several exact solutions for a higher-order nonlinear Schrodinger equation derived from one important model in the study of atmospheric and ocean dynamical systems. Our analytical solutions include bright and dark solitary waves, and periodical solutions, which can be used to explain atmospheric phenomena.

  13. Shape invariant higher-order Bessel-like beams carrying orbital angular momentum

    CSIR Research Space (South Africa)

    Ismail, Y

    2012-09-01

    Full Text Available We present a method for generating higher-order Bessel beams with z-dependent cone angles. Such fields, if engineered correctly, are shape invariant during propagation and thus do not suffer from a transition from a Bessel-shaped intensity profile...

  14. EXISTENCE OF PERIODIC SOLUTION TO HIGHER ORDER DIFFERENTIAL EQUATIONS WITH DEVIATING ARGUMENT

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper,using the coincidence degree theory of Mawhin,we investigate the existence of periodic solutions to higher order differential equations with deviating argument. Some new results on the existence of periodic solutions to the equations are obtained. In addition,we give an example to illustrate the main results.

  15. Massive, massless and ghost modes of gravitational waves from higher-order gravity

    DEFF Research Database (Denmark)

    Bogdanos, Charalampos; Capozziello, Salvatore; De Laurentis, Mariafelicia

    We linearize the field equations for higher order theories that contain scalar invariants other than the Ricci scalar. We find that besides a massless spin-2 field (the standard graviton), the theory contains also spin-0 and spin-2 massive modes with the latter being, in general, ghost modes. The...

  16. Performance-Based Task Assessment of Higher-Order Proficiencies in Redesigned STEM High Schools

    Science.gov (United States)

    Ernst, Jeremy V.; Glennie, Elizabeth; Li, Songze

    2017-01-01

    This study explored student abilities in applying conceptual knowledge when presented with structured performance tasks. Specifically, the study gauged proficiency in higher-order applications of students enrolled in earth and environmental science or biology. The student sample was drawn from a Redesigned STEM high school model where a tested…

  17. A Probabilistic Model of Visual Working Memory: Incorporating Higher Order Regularities into Working Memory Capacity Estimates

    Science.gov (United States)

    Brady, Timothy F.; Tenenbaum, Joshua B.

    2013-01-01

    When remembering a real-world scene, people encode both detailed information about specific objects and higher order information like the overall gist of the scene. However, formal models of change detection, like those used to estimate visual working memory capacity, assume observers encode only a simple memory representation that includes no…

  18. ON THE GROWTH OF SOLUTIONS OF A CLASS OF HIGHER ORDER DIFFERENTIAL EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    陈宗煊; 孙光镐

    2004-01-01

    In this paper, authors investigate the order of growth and the hyper order of solutions of a class of the higher order linear differential equation, and improve results of M. Ozawa[6], G. Gundersen[7] and J.K. Langley[8], Li Chun-hong[11].

  19. Topology optimized design of a transverse electric higher order mode converter

    DEFF Research Database (Denmark)

    Frellsen, Louise Floor; Ding, Yunhong; Sigmund, Ole

    2016-01-01

    present the possibility of employing topology optimization (TO) to design a device that allows for reversible conversion between the transverse electric fundamental even (TE0) mode and the second higher order odd mode (TE2). Topology optimization is an iterative inverse design process, where repeated...

  20. The advantage of higher-order theory of mind in the game of limited bidding

    NARCIS (Netherlands)

    De Weerd, H.; Verheij, B.; van Eijck, J.; Verbrugge, L. C.

    2011-01-01

    Higher-order theory of mind is the ability to recursively model mental states of other agents. It is known that adults in general can reason adequately at the second order (covering attributions like "Alice knows that Bob knows that she wrote a novel under pseudonym"), but there are cognitive limits

  1. Conception of Teaching Higher Order Thinking: Perspectives of Chinese Teachers in Hong Kong

    Science.gov (United States)

    Yeung, Sze-yin Shirley

    2015-01-01

    Enhancing the higher order thinking (HOT) ability of students is a worldwide educational goal. This has also become a significant objective in the curriculum reforms in Hong Kong, which aims at better preparation of students to meet the challenges of the new era. Cultural aspects are often regarded as salient in determining approaches to teaching.…

  2. Improving Higher Order Thinking Skills among Freshmen by Teaching Science through Inquiry

    Science.gov (United States)

    Hugerat, Muhamad; Kortam, Naji

    2014-01-01

    Twenty-eight freshmen majoring in biology and/or chemistry in an Arab college in Israel, were given a pre-test and a post-test in which they had to identify the control group and design a controlled experiment. During the course an intervention was used. Science was taught by inquiry while using strategies that promote higher-order thinking skills…

  3. m Components-Admissible Solutions of Systems of Higher-Order Partial Differential Equations on Cm

    Institute of Scientific and Technical Information of China (English)

    Ling-yun Gao

    2008-01-01

    Using value distribution theory and techniques in severed complex variables,we investigate the problem of existence of m components-admissible solutions of a class of systems of higher-order partied differential equations in several complex variables and estimate the number of admissible components of solutions.Some related results will also be obtained.

  4. Developing Higher-Order Thinking Skills through the Use of Technology.

    Science.gov (United States)

    Coleman, Connie; King, Jeff; Ruth, Mary Helen; Stary, Erin

    This report describes a program, utilizing both critical and creative thinking skills, to enhance the educational process through the use of technology. The targeted population consisted of fourth grade students in a growing middle class community located in northern Illinois. The lack of higher-order thinking skills was documented through…

  5. On the decay of higher order derivatives of solutions to Ladyzhenskaya model for incompressible viscous flows

    Institute of Scientific and Technical Information of China (English)

    DONG BoQing; JIANG Wei

    2008-01-01

    This article concerns large time behavior of Ladyzhenskaya model for incompressible viscous flows in R3. Based on linear Lp-Lq estimates, the auxiliary decay properties of the solutions and generalized Gronwall type arguments, some optimal upper and lower bounds for the decay of higher order derivatives of solutions are derived without assuming any decay properties of solutions and using Fourier splitting technology.

  6. The Higher Order Factor Structure and Gender Invariance of the Pathological Narcissism Inventory

    Science.gov (United States)

    Wright, Aidan G. C.; Lukowitsky, Mark R.; Pincus, Aaron L.; Conroy, David E.

    2010-01-01

    The Pathological Narcissism Inventory (PNI) is a recently developed multidimensional inventory for the assessment of pathological narcissism. The authors describe and report the results of two studies that investigate the higher order factor structure and gender invariance of the PNI. The results of the first study indicate that the PNI has a…

  7. Dichotomous Identification Keys: A Ladder to Higher Order Knowledge about the Human Body

    Science.gov (United States)

    Sorgo, Andrej

    2006-01-01

    We tried to enrich teaching human anatomy in high school biology lessons. Students construct dichotomous identification keys to the cells, tissues, organs, or body parts. By doing this, students have achieved higher-order cognitive levels of knowledge because construction of such keys is based on analysis, synthesis, and evaluation. Students found…

  8. An Initial Framework for the Language of Higher-Order Thinking Mathematics Practices

    Science.gov (United States)

    Staples, Megan E.; Truxaw, Mary P.

    2012-01-01

    This article presents an examination of the language demands of cognitively demanding tasks and proposes an initial framework for the language demands of higher-order mathematics thinking practices. We articulate four categories for this framework: "language of generalisation," "language of comparison," "language of proportional reasoning," and…

  9. Temperature variation of higher-order elastic constants of MgO

    Indian Academy of Sciences (India)

    K M Raju; R K Srivastava; Kailash

    2007-09-01

    An effort has been made for obtaining higher-order elastic constants for MgO starting from basic parameters, viz. nearest-neighbor distance and hardness parameter using Coulomb and Börn–Mayer potentials. These are calculated in a wide temperature range (100–1000 K) and compared with available theoretical and experimental results.

  10. Higher-Order Fertility among Urban Fathers: An Overlooked Issue for a Neglected Population

    Science.gov (United States)

    Bronte-Tinkew, Jacinta; Ryan, Suzanne; Franzetta, Kerry; Manlove, Jennifer; Lilja, Emily

    2009-01-01

    The study includes a longitudinal sample of 1,989 fathers from the Fragile Families and Child Wellbeing study and examines factors associated with fathering a higher-order birth (three or more children) and compares these factors to those predicting any subsequent birth. Also, the article examines differences by marital status. Logistic regression…

  11. Exact boundary controllability for higher order nonlinear Schrodinger equations with constant coefficients

    Directory of Open Access Journals (Sweden)

    Juan Carlos Ceballos V.

    2005-10-01

    Full Text Available The exact boundary controllability of the higher order nonlinear Schrodinger equation with constant coefficients on a bounded domain with various boundary conditions is studied. We derive the exact boundary controllability for this equation for sufficiently small initial and final states.

  12. Experimental validation of the Higher-Order Theory approach for sandwich panels with flexible core materials

    NARCIS (Netherlands)

    Straalen, IJ.J. van

    2000-01-01

    During tthe 1990's the higher-order theory was developed by Frostig to enable detailed stress analyses of sandwich panel structures. To investigate the potentials of this approach experiments are performed on sandwich panels made of thin steel faces and mineral wool or polystyrene core material. A p

  13. Dissolution risks in first and higher order marital and cohabiting unions

    NARCIS (Netherlands)

    Poortman, Anne-Rigt; Lyngstad, Torkild Hovde

    2007-01-01

    More and more people enter multiple unions during their lives, and then they may choose to either cohabit or marry. We examine the implications of this diversity in partnership trajectories by assessing dissolution risks in first and higher order marital and cohabiting unions. We use recent Norwegia

  14. Comparing higher order models for the EORTC QLQ-C30

    NARCIS (Netherlands)

    Gundy, C.M.; Fayers, P.M.; Groenvold, M.; Petersen, M.A.; Scott, N.W.; Sprangers, M.A.G.; Velikova, G.; Aaronson, N.K.

    2012-01-01

    Purpose To investigate the statistical fit of alternative higher order models for summarizing the health-related quality of life profile generated by the EORTC QLQ-C30 questionnaire. Methods A 50% random sample was drawn from a dataset of more than 9,000 pre-treatment QLQ-C30 v 3.0 questionnaires co

  15. Second- and Higher-Order Virial Coefficients Derived from Equations of State for Real Gases

    Science.gov (United States)

    Parkinson, William A.

    2009-01-01

    Derivation of the second- and higher-order virial coefficients for models of the gaseous state is demonstrated by employing a direct differential method and subsequent term-by-term comparison to power series expansions. This communication demonstrates the application of this technique to van der Waals representations of virial coefficients.…

  16. Strategic Learning in Youth with Traumatic Brain Injury: Evidence for Stall in Higher-Order Cognition

    Science.gov (United States)

    Gamino, Jacquelyn F.; Chapman, Sandra B.; Cook, Lori G.

    2009-01-01

    Little is known about strategic learning ability in preteens and adolescents with traumatic brain injury (TBI). Strategic learning is the ability to combine and synthesize details to form abstracted gist-based meanings, a higher-order cognitive skill associated with frontal lobe functions and higher classroom performance. Summarization tasks were…

  17. Higher Order Mean Squared Error of Generalized Method of Moments Estimators for Nonlinear Models

    Directory of Open Access Journals (Sweden)

    Yi Hu

    2014-01-01

    Full Text Available Generalized method of moments (GMM has been widely applied for estimation of nonlinear models in economics and finance. Although generalized method of moments has good asymptotic properties under fairly moderate regularity conditions, its finite sample performance is not very well. In order to improve the finite sample performance of generalized method of moments estimators, this paper studies higher-order mean squared error of two-step efficient generalized method of moments estimators for nonlinear models. Specially, we consider a general nonlinear regression model with endogeneity and derive the higher-order asymptotic mean square error for two-step efficient generalized method of moments estimator for this model using iterative techniques and higher-order asymptotic theories. Our theoretical results allow the number of moments to grow with sample size, and are suitable for general moment restriction models, which contains conditional moment restriction models as special cases. The higher-order mean square error can be used to compare different estimators and to construct the selection criteria for improving estimator’s finite sample performance.

  18. Encouraging Higher-Order Thinking in General Chemistry by Scaffolding Student Learning Using Marzano's Taxonomy

    Science.gov (United States)

    Toledo, Santiago; Dubas, Justin M.

    2016-01-01

    An emphasis on higher-order thinking within the curriculum has been a subject of interest in the chemical and STEM literature due to its ability to promote meaningful, transferable learning in students. The systematic use of learning taxonomies could be a practical way to scaffold student learning in order to achieve this goal. This work proposes…

  19. Higher-order singletons, partially massless fields, and their boundary values in the ambient approach

    Energy Technology Data Exchange (ETDEWEB)

    Bekaert, Xavier [Laboratoire de Mathématiques et Physique Théorique, Unité Mixte de Recherche 7350 du CNRS, Fédération de Recherche 2964 Denis Poisson, Université François Rabelais, Parc de Grandmont, 37200 Tours (France); Grigoriev, Maxim, E-mail: grig@lpi.ru [Tamm Theory Department, Lebedev Physics Institute, Leninsky prospect 53, 119991 Moscow (Russian Federation)

    2013-11-11

    Using ambient space we develop a fully gauge and o(d,2)-covariant approach to boundary values of AdS{sub d+1} gauge fields. It is applied to the study of (partially) massless fields in the bulk and (higher-order) conformal scalars, i.e. singletons, as well as (higher-depth) conformal gauge fields on the boundary. In particular, we identify the corresponding generalized Fradkin–Tseytlin equations as obstructions to the extension of the off-shell boundary value to the bulk, generalizing the usual considerations for the holographic anomalies to the partially massless fields. We also relate the background fields for the higher-order singleton to the boundary values of partially massless fields and prove the appropriate generalization of the Flato–Fronsdal theorem, which is in agreement with the known structure of symmetries for the higher-order wave operator. All these facts support the following generalization of the higher-spin holographic duality: the O(N) model at a multicritical isotropic Lifshitz point should be dual to the theory of partially massless symmetric tensor fields described by the Vasiliev equations based on the higher-order singleton symmetry algebra.

  20. Higher Order, Critical Thinking Skills in National Police Academy Course Development

    Science.gov (United States)

    Barker, Beth A.

    2011-01-01

    Law enforcement requires the officer to invoke reason and critical thinking skills in order to solve intricate problems in real time, on the job. This study examined the course development of a large national organization (State Police Academies) to ascertain what strategies are being used in their courses to promote training for higher order,…

  1. Orthogonal Higher Order Structure of the WISC-IV Spanish Using Hierarchical Exploratory Factor Analytic Procedures

    Science.gov (United States)

    McGill, Ryan J.; Canivez, Gary L.

    2016-01-01

    As recommended by Carroll, the present study examined the factor structure of the Wechsler Intelligence Scale for Children-Fourth Edition Spanish (WISC-IV Spanish) normative sample using higher order exploratory factor analytic techniques not included in the WISC-IV Spanish Technical Manual. Results indicated that the WISC-IV Spanish subtests were…

  2. A Hybrid PO - Higher-Order Hierarchical MoM Formulation using Curvilinear Geometry Modeling

    DEFF Research Database (Denmark)

    Jørgensen, E.; Meincke, Peter; Breinbjerg, Olav

    2003-01-01

    A very efficient hybrid PO-MoM method has been presented. In contrast to existing methods, the present solution employs higher-order hierarchical basis functions to discretize the MoM and PO currents. This allows to reduce the number of basis functions in both the PO and MoM regions considerably...

  3. BOUNDEDNESS OF HIGHER ORDER COMMUTATORS OF GENERALIZED FRACTIONAL INTEGRAL OPERATORS ON HARDY SPACES

    Institute of Scientific and Technical Information of China (English)

    Chunlei He; Lisheng Shu

    2005-01-01

    Let Tμ,b,m be the higher order commutator generated by a generalized fractional integral operator Tμ and a BMO function b. In this paper, we will study the boundedness of Tμ,b,m on classical Hardy spaces and Herz-type Hardy spaces.

  4. Higher order equivalent edge currents for fringe wave radar scattering by perfectly conducting polygonal plates

    DEFF Research Database (Denmark)

    Breinbjerg, Olav

    1992-01-01

    An approach for including higher order edge diffraction in the equivalent edge current (EEC) method is proposed. This approach, which applies to monostatic as well as bistatic radar configurations with perfectly conducting polygonal plates, involves three distinct sets of EECs. All of these sets ...

  5. Problem-Based Learning and Use of Higher-Order Thinking by Emergency Medical Technicians

    Science.gov (United States)

    Rosenberger, Paul

    2013-01-01

    Emergency Medical Technicians (EMTs) often handle chaotic life-and-death situations that require higher-order thinking skills. Improving the pass rate of EMT students depends on many factors, including the use of proven and effective teaching methods. Results from recent research about effective teaching have suggested that the instructional…

  6. Experimental generation and application of the superposition of higher-order Bessel beams

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2009-07-01

    Full Text Available This presentation provides information on experimental generation and application of the superposition of higher-order Bessel beams. The superposition of zero order Bessel beams can be used to measure the radius of curvature of a reflecting surface...

  7. On realization of nonlinear systems described by higher-order differential equations

    NARCIS (Netherlands)

    Schaft, van der A.J.

    1987-01-01

    We consider systems of smooth nonlinear differential and algebraic equations in which some of the variables are distinguished as “external variables.” The realization problem is to replace the higher-order implicit differential equations by first-order explicit differential equations and the algebra

  8. THE SINGULARLY PERTURBED BOUNDARY VALUE PROBLEMS FOR SEMILINEAR ELLIPTIC EQUATION OF HIGHER ORDER

    Institute of Scientific and Technical Information of China (English)

    Chen Songlin; Mo Jiaqi

    2000-01-01

    The singularly perturbed boundary value problems for the semilinear elliptic equation of higher order are considered. Under suitable conditions and by using the fixed point theoren the existence, uniqueness and asymp totic behavior of solution for the boundary value tproblems are studied.

  9. Electrophysiological correlates of associative learning in smokers: a higher-order conditioning experiment

    Directory of Open Access Journals (Sweden)

    Littel Marianne

    2012-01-01

    Full Text Available Abstract Background Classical conditioning has been suggested to play an important role in the development, maintenance, and relapse of tobacco smoking. Several studies have shown that initially neutral stimuli that are directly paired with smoking are able to elicit conditioned responses. However, there have been few human studies that demonstrate the contribution of higher-order conditioning to smoking addiction, although it is assumed that higher-order conditioning predominates learning in the outside world. In the present study a higher-order conditioning task was designed in which brain responses of smokers and non-smokers were conditioned by pairing smoking-related and neutral stimuli (CS1smoke and CS1neutral with two geometrical figures (CS2smoke and CS2neutral. ERPs were recorded to all CSs. Results Data showed that the geometrical figure that was paired with smoking stimuli elicited significantly larger P2 and P3 waves than the geometrical figure that was paired with neutral stimuli. During the first half of the experiment this effect was only present in smokers whereas non-smokers displayed no significant differences between both stimuli, indicating that neutral cues paired with motivationally relevant smoking-related stimuli gain more motivational significance even though they were never paired directly with smoking. These conclusions are underscored by self-reported evidence of enhanced second-order conditioning in smokers. Conclusions It can be concluded that smokers show associative learning for higher-order smoking-related stimuli. The present study directly shows the contribution of higher-order conditioning to smoking addiction and is the first to reveal its electrophysiological correlates. Although results are preliminary, they may help in understanding the etiology of smoking addiction and its persistence.

  10. From higher order thinking to higher order behavior: exploring the relationship between early cognitive skills and social competence in black boys.

    Science.gov (United States)

    Scott, Kristin M; Barbarin, Oscar A; Brown, Jeffrey M

    2013-01-01

    This study examines the relations of higher order (i.e., abstract) thinking (HOT) skills to specific domains of social competence in Black boys (n = 108) attending publicly sponsored prekindergarten (pre-K) programs. Data for the study were collected as part of the National Center for Early Development and Learning (NCEDL) Multi-State Study, a national, longitudinal study examining the quality and outcomes in a representative sample of publicly sponsored pre-K programs in six states (N = 240). Pre-K and kindergarten teachers rated randomly selected children on measures of abstract thinking, self-regulation, and social functioning at the beginning and end of each school year. Applying structural equation modeling, compared with earlier time points, HOT measured in the fall of kindergarten significantly predicted each of the domains of social competence in the spring of kindergarten, with the exception of peer social skills, while controlling for general cognitive ability. Results suggest that early intervention to improve HOT may be an effective and more focused approach to address concerns about Black boys' early social competencies in specific domains and potentially reduce the risk of later social difficulties. © 2013 American Orthopsychiatric Association.

  11. Generation of higher order nonclassical states via interaction of intense electromagnetic field with third order nonlinear medium

    CERN Document Server

    Pathak, A

    2006-01-01

    Interaction of intense laser beam with an inversion symmetric third order nonlinear medium is modeled as a quartic anharmonic oscillator. A first order operator solution of the model Hamiltonian is used to study the possibilities of generation of higher order nonclassical states. It is found that the higher order squeezed and higher order antibunched states can be produced by this interaction. It is also shown that the higher order nonclassical states may appear separately, i.e. a higher order antibunched state is not essentially higher order squeezed state and vice versa.

  12. Conformal Invariance of Higher-Order Lagrange Systems by Lie Point Transformation

    Institute of Scientific and Technical Information of China (English)

    HUANG Wei-Li; CAI Jian-Le

    2011-01-01

    Conformal invariance and conserved quantities for a higher-order Lagrange system by Lie point transformation of groups are studied. The differential equation of motion for the higher-order Lagrange system is introduced. The definition of conformal invariance for the system together with its determining equations and conformal factor are provided. The necessary and sufficient condition that the system's conformal invariance would be Lie symmetry by the infinitesimal one-parameter point transformation group is deduced. The conserved quantity of the system is derived using the structural equation satisfied by the gauge function. An example of a higher-order mechanical system is offered to illustrate the application of the result.%Conformal invariance and conserved quantities for a higher-order Lagrange system by Lie point transformation of groups are studied.The differential equation of motion for the higher-order Lagrange system is introduced.The definition of conformal invariance for the system together with its determining equations and conformal factor are provided.The necessary and sufficient condition that the system's conformal invariance would be Lie symmetry by the infinitesimal one-parameter point transformation group is deduced.The conserved quantity of the system is derived using the structural equation satisfied by the gauge function.An example of a higher-order mechanical system is offered to illustrate the application of the result.Since the Noether theorem was published in 1918,[1] the symmetry and conserved quantity for a dynamical system play important roles in the fields of modern science and technology,and some important results have been gained so far.[2-21] Conformal invariance is a modern method for finding conserved quantities.In 1997,Galiullin etal.[22] studied conformal invariance of Birkhoff systems under special infinitesimal transformations.In recent years,we have discussed the conformal invariance of Lie symmetry for Lagrange systems

  13. REVISION AND REWRITING IN OFFICIAL DOCUMENTS: CONCEPTS AND METHODOLOGICAL ORIENTATIONS

    Directory of Open Access Journals (Sweden)

    Renilson José MENEGASSI

    2014-12-01

    Full Text Available The text discuss how the concepts and the methodological orientations about text revision and rewriting processes, in teaching context, are conceived, presented and guide the Portuguese Language teacher’s work. To this end, the concepts of revision and rewriting are characterized in four Brazilian official documents, two from national scope and two from Paraná state. The information was organized from what the documents show about the teacher and student attitude face to the investigated concepts, which determine the methodological orientations to the text production work. The results show irregularities in these processes handling, highlighting one of the official documents, from national scope, as the one that presents more suitable methodological and conceptual orientations. It shows that the documents which guide the mother language teaching in the country are still not appropriately discussing the writing text production process, specifically the revision and rewriting, even in more recent documents.

  14. Proceedings International Workshop on Strategies in Rewriting, Proving, and Programming

    CERN Document Server

    Kirchner, Hélène; 10.4204/EPTCS.44

    2010-01-01

    This volume contains selected papers from the proceedings of the First International Workshop on Strategies in Rewriting, Proving, and Programming (IWS 2010), which was held on July 9, 2010, in Edinburgh, UK. Strategies are ubiquitous in programming languages, automated deduction and reasoning systems. In the two communities of Rewriting and Programming on one side, and of Deduction and Proof engines (Provers, Assistants, Solvers) on the other side, workshops have been launched to make progress towards a deeper understanding of the nature of strategies, their descriptions, their properties, and their usage, in all kinds of computing and reasoning systems. Since more recently, strategies are also playing an important role in rewrite-based programming languages, verification tools and techniques like SAT/SMT engines or termination provers. Moreover strategies have come to be viewed more generally as expressing complex designs for control in computing, modeling, proof search, program transformation, and access c...

  15. Productivity of Non-Orthogonal Term Rewrite Systems

    CERN Document Server

    Raffelsieper, Matthias

    2012-01-01

    Productivity is the property that finite prefixes of an infinite constructor term can be computed using a given term rewrite system. Hitherto, productivity has only been considered for orthogonal systems, where non-determinism is not allowed. This paper presents techniques to also prove productivity of non-orthogonal term rewrite systems. For such systems, it is desired that one does not have to guess the reduction steps to perform, instead any outermost-fair reduction should compute an infinite constructor term in the limit. As a main result, it is shown that for possibly non-orthogonal term rewrite systems this kind of productivity can be concluded from context-sensitive termination. This result can be applied to prove stabilization of digital circuits, as will be illustrated by means of an example.

  16. Lifting Term Rewriting Derivations in Constructor Systems by Using Generators

    Directory of Open Access Journals (Sweden)

    Adrián Riesco

    2015-01-01

    Full Text Available Narrowing is a procedure that was first studied in the context of equational E-unification and that has been used in a wide range of applications. The classic completeness result due to Hullot states that any term rewriting derivation starting from an instance of an expression can be "lifted" to a narrowing derivation, whenever the substitution employed is normalized. In this paper we adapt the generator- based extra-variables-elimination transformation used in functional-logic programming to overcome that limitation, so we are able to lift term rewriting derivations starting from arbitrary instances of expressions. The proposed technique is limited to left-linear constructor systems and to derivations reaching a ground expression. We also present a Maude-based implementation of the technique, using natural rewriting for the on-demand evaluation strategy.

  17. Generalized quantum kinetic expansion: Higher-order corrections to multichromophoric Förster theory.

    Science.gov (United States)

    Wu, Jianlan; Gong, Zhihao; Tang, Zhoufei

    2015-08-21

    For a general two-cluster energy transfer network, a new methodology of the generalized quantum kinetic expansion (GQKE) method is developed, which predicts an exact time-convolution equation for the cluster population evolution under the initial condition of the local cluster equilibrium state. The cluster-to-cluster rate kernel is expanded over the inter-cluster couplings. The lowest second-order GQKE rate recovers the multichromophoric Förster theory (MCFT) rate. The higher-order corrections to the MCFT rate are systematically included using the continued fraction resummation form, resulting in the resummed GQKE method. The reliability of the GQKE methodology is verified in two model systems, revealing the relevance of higher-order corrections.

  18. Signal Processing and Sampling Method for Obtaining Time Series Corresponding to Higher Order Derivatives

    Directory of Open Access Journals (Sweden)

    Andreea Sterian

    2010-01-01

    accuracy some significant quantities corresponding to the dynamic system. For fast phenomena, such significant quantities are represented by the derivatives of the received signals. In case of advanced computer modeling, the received signal should be filtered and converted into a time series corresponding to the estimated values for the dynamic system through a sampling procedure. This paper will show that present-day methods for computing in a robust manner the first derivative of a received signal (using an oscillating system working on a limited time interval and a supplementary differentiation method can be extended to the robust computation of higher order derivatives of the received signal by using a specific set of second-order oscillating systems (working also on limited time intervals so as estimative values for higher-order derivatives are to be directly generated (avoiding the necessity of additional differentiation or amplifying procedures, which represent a source of supplementary errors in present-day methods.

  19. Higher-order numerical methods derived from three-point polynomial interpolation

    Science.gov (United States)

    Rubin, S. G.; Khosla, P. K.

    1976-01-01

    Higher-order collocation procedures resulting in tridiagonal matrix systems are derived from polynomial spline interpolation and Hermitian finite-difference discretization. The equations generally apply for both uniform and variable meshes. Hybrid schemes resulting from different polynomial approximations for first and second derivatives lead to the nonuniform mesh extension of the so-called compact or Pade difference techniques. A variety of fourth-order methods are described and this concept is extended to sixth-order. Solutions with these procedures are presented for the similar and non-similar boundary layer equations with and without mass transfer, the Burgers equation, and the incompressible viscous flow in a driven cavity. Finally, the interpolation procedure is used to derive higher-order temporal integration schemes and results are shown for the diffusion equation.

  20. Finite time control for MIMO nonlinear system based on higher-order sliding mode.

    Science.gov (United States)

    Liu, Xiangjie; Han, Yaozhen

    2014-11-01

    Considering a class of MIMO uncertain nonlinear system, a novel finite time stable control algorithm is proposed based on higher-order sliding mode concept. The higher-order sliding mode control problem of MIMO nonlinear system is firstly transformed into finite time stability problem of multivariable system. Then continuous control law, which can guarantee finite time stabilization of nominal integral chain system, is employed. The second-order sliding mode is used to overcome the system uncertainties. High frequency chattering phenomenon of sliding mode is greatly weakened, and the arbitrarily fast convergence is reached. The finite time stability is proved based on the quadratic form Lyapunov function. Examples concerning the triple integral chain system with uncertainty and the hovercraft trajectory tracking are simulated respectively to verify the effectiveness and the robustness of the proposed algorithm.

  1. Higher order effects in non-linear evolution from a veto in rapidities

    Science.gov (United States)

    Chachamis, G.; Lublinsky, M.; Sabio Vera, A.

    2005-02-01

    Higher order corrections to the Balitsky-Kovchegov equation have been estimated by introducing a rapidity veto which forbids subsequent emissions to be very close in rapidity and is known to mimic higher order corrections to the linear BFKL equation. The rapidity veto constraint has been first introduced using analytical arguments obtaining a power growth with energy, Q(Y)˜e, of the saturation scale of λ˜0.45. Then a numerical analysis for the non-linear Balitsky-Kovchegov equation has been carried out for phenomenological rapidities: when a veto of about two units of rapidity is introduced for a fixed value of the coupling constant of α=0.2 the saturation scale λ decreases from ˜0.6 to ˜0.3, and when running coupling effects are taken into account it decreases from ˜0.4 to ˜0.3.

  2. John Carroll’s Views on Intelligence: Bi-Factor vs. Higher-Order Models

    Directory of Open Access Journals (Sweden)

    A. Alexander Beaujean

    2015-10-01

    Full Text Available The development of factor models is inextricably tied to the history of intelligence research. One of the most commonly-cited scholars in the field is John Carroll, whose three-stratum theory of cognitive ability has been one of the most influential models of cognitive ability in the past 20 years. Nonetheless, there is disagreement about how Carroll conceptualized the factors in his model. Some argue that his model is best represented through a higher-order model, while others argue that a bi-factor model is a better representation. Carroll was explicit about what he perceived the best way to represent his model, but his writings are not always easy to understand. In this article, I clarify his position by first describing the details and implications of bi-factor and higher-order models then show that Carroll’s published views are better represented by a bi-factor model.

  3. Hybrid: A Definitional Two-Level Approach to Reasoning with Higher-Order Abstract Syntax

    CERN Document Server

    Felty, Amy

    2008-01-01

    Combining higher-order abstract syntax and (co)induction in a logical framework is well known to be problematic. Previous work described the implementation of a tool called Hybrid, within Isabelle HOL, which aims to address many of these difficulties. It allows object logics to be represented using higher-order abstract syntax, and reasoned about using tactical theorem proving and principles of (co)induction. In this paper we describe how to use it in a multi-level reasoning fashion, similar in spirit to other meta-logics such as Twelf. By explicitly referencing provability in a middle layer called a specification logic, we solve the problem of reasoning by (co)induction in the presence of non-stratifiable hypothetical judgments, which allow very elegant and succinct specifications of object logic inference rules.

  4. Application of higher-order numerical methods to the boundary-layer equations

    Science.gov (United States)

    Wornom, S. F.

    1978-01-01

    A fourth-order method is presented for calculating numerical solutions to parabolic, partial differential equations in two variables or ordinary differential equations. The method is the natural extension of the second-order Keller Box Scheme to fourth order and is demonstrated with application to the incompressible, laminar and turbulent boundary-layer equations for both attached and separated flows. The efficiency of the present method is compared with other higher-order methods; namely, the Keller Box Scheme with Richardson extrapolation, the method of deferred corrections, the three-point spline methods, and a modified finite-element method. For equivalent accuracy, numerical results show the present method to be more efficient than the other higher-order methods for both laminar and turbulent flows.

  5. Robust rooftop extraction from visible band images using higher order CRF

    KAUST Repository

    Li, Er

    2015-08-01

    In this paper, we propose a robust framework for building extraction in visible band images. We first get an initial classification of the pixels based on an unsupervised presegmentation. Then, we develop a novel conditional random field (CRF) formulation to achieve accurate rooftops extraction, which incorporates pixel-level information and segment-level information for the identification of rooftops. Comparing with the commonly used CRF model, a higher order potential defined on segment is added in our model, by exploiting region consistency and shape feature at segment level. Our experiments show that the proposed higher order CRF model outperforms the state-of-the-art methods both at pixel and object levels on rooftops with complex structures and sizes in challenging environments. © 1980-2012 IEEE.

  6. Parallel Higher-order Boundary Integral Electrostatics Computation on Molecular Surfaces with Curved Triangulation

    CERN Document Server

    Geng, Weihua

    2013-01-01

    In this paper, we present a parallel higher-order boundary integral method to solve the linear Poisson-Boltzmann (PB) equation. In our method, a well-posed boundary integral formulation is used to ensure the fast convergence of Krylov subspace linear solver such as GMRES. The molecular surfaces are first discretized with flat triangles and then converted to curved triangles with the assistance of normal information at vertices. To maintain the desired accuracy, four-point Gauss-Radau quadratures are used on regular triangles and sixteen-point Gauss-Legendre quadratures together with regularization transformations are applied on singular triangles. To speed up our method, we take advantage of the embarrassingly parallel feature of boundary integral formulation, and parallelize the schemes with the message passing interface (MPI) implementation. Numerical tests show significantly improved accuracy and convergence of the proposed higher-order boundary integral Poisson-Boltzmann (HOBI-PB) solver compared with bou...

  7. Space-demultiplexing based on higher-order Poincaré spheres.

    Science.gov (United States)

    Fernandes, Gil M; Muga, Nelson J; Pinto, Armando N

    2017-02-20

    We propose a space-demultiplexing algorithm based on signal analysis in higher-order Poincaré spheres for optical transmission systems supported by space-division multiplexing. This algorithm is modulation format agnostic and does not require training sequences. We show that any arbitrary pair of tributaries signals can be represented in a higher-order Poincaré sphere. In such sphere, the crosstalk between any two tributary signals can be reversed by computing and realigning the best fit plane. Using this procedure for all possible combinations of tributaries the transmitted signal is successfully recovered, with negligible signal-to-noise ratio (SNR) penalties for quadrature phase-shift keying (QPSK) and 16-quadrature amplitude modulation (QAM) constellations, and with a SNR penalty as lower as 0.5 dB for the 64-QAM.

  8. Novel asymmetric representation method for solving the higher-order Ginzburg-Landau equation.

    Science.gov (United States)

    Wong, Pring; Pang, Lihui; Wu, Ye; Lei, Ming; Liu, Wenjun

    2016-04-18

    In ultrafast optics, optical pulses are generated to be of shorter pulse duration, which has enormous significance to industrial applications and scientific research. The ultrashort pulse evolution in fiber lasers can be described by the higher-order Ginzburg-Landau (GL) equation. However, analytic soliton solutions for this equation have not been obtained by use of existing methods. In this paper, a novel method is proposed to deal with this equation. The analytic soliton solution is obtained for the first time, and is proved to be stable against amplitude perturbations. Through the split-step Fourier method, the bright soliton solution is studied numerically. The analytic results here may extend the integrable methods, and could be used to study soliton dynamics for some equations in other disciplines. It may also provide the other way to obtain two-soliton solutions for higher-order GL equations.

  9. Rayleigh scattering in an optical nanofiber as a probe of higher-order mode propagation

    CERN Document Server

    Hoffman, Jonathan E; Beadie, Guy; Rolston, Steven L; Orozco, Luis A

    2015-01-01

    Optical nanofibers provide a rich platform for exploring atomic and optical phenomena even when they support only a single spatial mode. Nanofibers supporting higher-order modes provide additional degrees of freedom to enable complex evanescent field profiles for interaction with the surrounding medium, but local control of these profiles requires nondestructive evaluation of the propagating fields. Here, we use Rayleigh scattering for rapid measurement of the propagation of light in few-mode optical nanofibers. Imaging the Rayleigh scattered light provides direct visualization of the spatial evolution of propagating fields throughout the entire fiber, including the transition from core-cladding guidance to cladding-air guidance. We resolve the interference between higher-order modes to determine local beat lengths and modal content along the fiber, and show that the modal superposition in the waist can be systematically controlled by adjusting the input superposition. With this diagnostic we can measure vari...

  10. Benchmark experiments for higher-order and full-Stokes ice sheet models (ISMIP–HOM

    Directory of Open Access Journals (Sweden)

    F. Pattyn

    2008-08-01

    Full Text Available We present the results of the first ice sheet model intercomparison project for higher-order and full-Stokes ice sheet models. These models are compared and verified in a series of six experiments of which one has an analytical solution obtained from a perturbation analysis. The experiments are applied to both 2-D and 3-D geometries; five experiments are steady-state diagnostic, and one has a time-dependent prognostic solution. All participating models give results that are in close agreement. A clear distinction can be made between higher-order models and those that solve the full system of equations. The full-Stokes models show a much smaller spread, hence are in better agreement with one another and with the analytical solution.

  11. Benchmark experiments for higher-order and full Stokes ice sheet models (ISMIP-HOM

    Directory of Open Access Journals (Sweden)

    F. Pattyn

    2008-02-01

    Full Text Available We present the results of the first ice sheet model intercomparison project for higher-order and full Stokes ice sheet models. These models are validated in a series of six benchmark experiments of which one has an analytical solution under simplifying assumptions. Five of the tests are diagnostic and one experiment is prognostic or time dependent, for both 2-D and 3-D geometries. The results show a good convergence of the different models even for high aspect ratios. A clear distinction can be made between higher-order models and those that solve the full system of equations. The latter show a significantly better agreement with each other as well as with analytical solutions, which demonstrates that they are hardly influenced by the used numerics.

  12. Enhancing Higher Order Thinking Skills Among Inservice Science Teachers Via Embedded Assessment

    Science.gov (United States)

    Barak, Miri; Dori, Yehudit Judy

    2009-10-01

    Testing students on higher order thinking skills may reinforce these skills among them. To research this assertion, we developed a graduate course for inservice science teachers in a framework of a “Journal Club”—a hybrid course which combines face-to-face classroom discussions with online activities, interrelating teaching, learning, and assessment. The course involves graduate students in critical evaluation of science education articles and cognitive debates, and tests them on these skills. Our study examined the learning processes and outcomes of 51 graduate students, from three consecutive semesters. Findings indicated that the students’ higher order thinking skills were enhanced in terms of their ability to (a) pose complex questions, (b) present solid opinions, (c) introduce consistent arguments, and (d) demonstrate critical thinking.

  13. A new fuzzy multi-objective higher order moment portfolio selection model for diversified portfolios

    Science.gov (United States)

    Yue, Wei; Wang, Yuping

    2017-01-01

    Due to the important effect of the higher order moments to portfolio returns, the aim of this paper is to make use of the third and fourth moments for fuzzy multi-objective portfolio selection model. Firstly, in order to overcome the low diversity of the obtained solution set and lead to corner solutions for the conventional higher moment portfolio selection models, a new entropy function based on Minkowski measure is proposed as a new objective function and a novel fuzzy multi-objective weighted possibilistic higher order moment portfolio model is presented. Secondly, to solve the proposed model efficiently, a new multi-objective evolutionary algorithm is designed. Thirdly, several portfolio performance evaluation techniques are used to evaluate the performance of the portfolio models. Finally, some experiments are conducted by using the data of Shanghai Stock Exchange and the results indicate the efficiency and effectiveness of the proposed model and algorithm.

  14. An initial framework for the language of higher-order thinking mathematics practices

    Science.gov (United States)

    Staples, Megan E.; Truxaw, Mary P.

    2012-09-01

    This article presents an examination of the language demands of cognitively demanding tasks and proposes an initial framework for the language demands of higher-order mathematics thinking practices. We articulate four categories for this framework: language of generalisation, language of comparison, language of proportional reasoning, and language of analysing impact. These categories were developed out of our collaborative work to design and implement higher-order thinking tasks with a group of Grade 9 (14- and 15-year-olds) teachers teaching in a linguistically diverse setting; analyses of student work samples on these tasks; and our knowledge of the literature. We describe each type of language demand and then analyse student work in each category to reveal linguistic challenges facing students as they engage these mathematical tasks. Implications for teaching and professional development are discussed.

  15. Bearing fault identification by higher order energy operator fusion: A non-resonance based approach

    Science.gov (United States)

    Faghidi, H.; Liang, M.

    2016-10-01

    We report a non-resonance based approach to bearing fault detection. This is achieved by a higher order energy operator fusion (HOEO_F) method. In this method, multiple higher order energy operators are fused to form a single simple transform to process the bearing signal obscured by noise and vibration interferences. The fusion is guided by entropy minimization. Unlike the popular high frequency resonance technique, this method does not require the information of resonance excited by the bearing fault. The effects of the HOEO_F method on signal-to-noise ratio (SNR) and signal-to-interference ratio (SIR) are illustrated in this paper. The performance of the proposed method in handling noise and interferences has been examined using both simulated and experimental data. The results indicate that the HOEO_F method outperforms both the envelope method and the original energy operator method.

  16. Elements of Teachers' Pedagogical Knowledge Regarding Instruction of Higher Order Thinking

    Science.gov (United States)

    Zohar, Anat

    2004-08-01

    This study investigated elements of pedagogical knowledge when students'' higher order thinking was an explicit and focused instructional goal. The findings suggest a model that consists of 6 elements. It seems that, for all these elements, the source of differences between teachers'' various pedagogies may be tracked to the basic distinction between a traditional transmission-of-knowledge approach to instruction versus a reform oriented constructivist approach. The findings portray how these two pedagogies are played out when higher order thinking is viewed as a distinct educational goal. Appropriate activities are insufficient for students'' active thinking. In the absence of adequate pedagogies, teachers adopt algorithmic approaches for teaching thinking that decrease the cognitive demands of tasks. Practical recommendations are discussed.

  17. Higher-Order Structure in Bacterial VapBC Toxin-Antitoxin Complexes

    DEFF Research Database (Denmark)

    Bendtsen, Kirstine L; Brodersen, Ditlev E

    2017-01-01

    Toxin-antitoxin systems are widespread in the bacterial kingdom, including in pathogenic species, where they allow rapid adaptation to changing environmental conditions through selective inhibition of key cellular processes, such as DNA replication or protein translation. Under normal growth...... conditions, type II toxins are inhibited through tight protein-protein interaction with a cognate antitoxin protein. This toxin-antitoxin complex associates into a higher-order macromolecular structure, typically heterotetrameric or heterooctameric, exposing two DNA binding domains on the antitoxin...... that allow auto-regulation of transcription by direct binding to promoter DNA. In this chapter, we review our current understanding of the structural characteristics of type II toxin-antitoxin complexes in bacterial cells, with a special emphasis on the staggering variety of higher-order architecture...

  18. Maximal intensity higher-order Akhmediev breathers of the nonlinear Schrodinger equation and their systematic generation

    CERN Document Server

    Chin, Siu A; Nikolic, Stanko N; Belic, Milivoj R

    2016-01-01

    It is well known that Akhmediev breathers of the nonlinear cubic Schrodinger equation can be superposed nonlinearly via the Darboux transformation to yield breathers of higher order. Surprisingly, we find that the peak height of each Akhmediev breather only adds {\\it linearly} to form the peak height of the final breather. Using this new peak-height formula, we show that at any given periodicity, there exist a unique high-order breather of maximal intensity. Moreover, these high-order breathers form a continuous hierarchy, growing in intensity with increasing periodicity. For any such higher-order breather, a simple initial wave function can be extracted from the Darboux transformation to dynamically generate that breather from the nonlinear Schrodinger equation.

  19. Response spectrum method for extreme wave loading with higher order components of drag force

    Science.gov (United States)

    Reza, Tabeshpour Mohammad; Mani, Fatemi Dezfouli; Mohammad Ali, Dastan Diznab; Saied, Mohajernasab; Saied, Seif Mohammad

    2017-01-01

    Response spectra of fixed offshore structures impacted by extreme waves are investigated based on the higher order components of the nonlinear drag force. In this way, steel jacket platforms are simplified as a mass attached to a light cantilever cylinder and their corresponding deformation response spectra are estimated by utilizing a generalized single degree of freedom system. Based on the wave data recorded in the Persian Gulf region, extreme wave loading conditions corresponding to different return periods are exerted on the offshore structures. Accordingly, the effect of the higher order components of the drag force is considered and compared to the linearized state for different sea surface levels. When the fundamental period of the offshore structure is about one third of the main period of wave loading, the results indicate the linearized drag term is not capable of achieving a reliable deformation response spectrum.

  20. Distributed adaptive fuzzy iterative learning control of coordination problems for higher order multi-agent systems

    Science.gov (United States)

    Li, Jinsha; Li, Junmin

    2016-07-01

    In this paper, the adaptive fuzzy iterative learning control scheme is proposed for coordination problems of Mth order (M ≥ 2) distributed multi-agent systems. Every follower agent has a higher order integrator with unknown nonlinear dynamics and input disturbance. The dynamics of the leader are a higher order nonlinear systems and only available to a portion of the follower agents. With distributed initial state learning, the unified distributed protocols combined time-domain and iteration-domain adaptive laws guarantee that the follower agents track the leader uniformly on [0, T]. Then, the proposed algorithm extends to achieve the formation control. A numerical example and a multiple robotic system are provided to demonstrate the performance of the proposed approach.

  1. Higher-Order Corrections to Earthʼs Ionosphere Shocks

    Science.gov (United States)

    Abdelwahed, H. G.; El-Shewy, E. K.

    2017-01-01

    Nonlinear shock wave structures in unmagnetized collisionless viscous plasmas composed fluid of positive (negative) ions and nonthermally electron distribution are examined. For ion shock formation, a reductive perturbation technique applied to derive Burgers equation for lowest-order potential. As the shock amplitude decreasing or enlarging, its steepness and velocity deviate from Burger equation. Burgers type equation with higher order dissipation must be obtained to avoid this deviation. Solution for the compined two equations has been derived using renormalization analysis. Effects of higher-order, positive- negative mass ratio Q, electron nonthermal parameter δ and kinematic viscosities coefficient of positive (negative) ions {η }1 and {η }2 on the electrostatic shocks in Earth’s ionosphere are also argued. Supported by the Deanship of Scientific Research at Prince Sattam Bin Abdulaziz University under the Research Project No. 2015/01/4787

  2. Numerical solving for nonlinear using higher order homotopy Taylor-perturbation

    Directory of Open Access Journals (Sweden)

    Nor Hanim Abd Rahman

    2013-03-01

    Full Text Available Rootfinding is a classical problem that still remains an interest to many researchers. A series of hybrid methods called Higher Order Homotopy Taylor-perturbation method via start-system functions (HTTPss are implemented to give approximate solutions for nonlinear equations, . The techniques serve as alternative methods for obtaining approximate solutions for different types of nonlinear equations. Thus, this paper presents an analysis on numerical comparison between the classical Newton Raphson (CNR, Homotopy Perturbation method (HTPss and Higher Order Homotopy Taylor-perturbation via start-system (HHTPss. A computational system Maple14 is used for this paper. Numerical and Illustrative results reveal that HHTPss methods are acceptably accurate and applicable.

  3. A study of the higher order Lamb resonances on elastic shells: Their prediction and interpretation

    Science.gov (United States)

    Werby, M. F.; Broadhead, M. K.; Sadjadi, Firooz A.

    1992-04-01

    We study all the resonances generated on elastic shells for a ka from 0 to 500 for steel and aluminum for a thickness of 5%. We observe the lowest order symmetric and antisymmetric model or Lamb resonances, waterborne and pseudo-Stoneley resonances and the higher order Lamb modes A and S, where i = 1, 2, 3 ... . We plot some of the phase velocities of some of the relevant resonances out to a ka of 500 and indicate simple expressions that predict the onset of each of the resonances. We demonstrate by use of partial wave analysis that the new expressions that predict the onset (critical frequencies) of the higher order Lamb modes are reliable. Further, interesting phenomena occur at the inception of some of the resonances and we discuss some of those cases.

  4. Recurrent activity in higher order, modality non-specific brain regions

    DEFF Research Database (Denmark)

    Lou, Hans Olav Christensen; Joensson, Morten; Biermann-Ruben, Katja

    2011-01-01

    in the visual system as a response to visual stimulation. In contrast recurrent activity has never been demonstrated before in higher order modality non-specific regions. Using magneto-encephalography and Granger causality analysis, we tested in a paralimbic network the hypothesis that stimulation may enhance...... causal recurrent interaction between higher-order, modality non-specific regions. The network includes anterior cingulate/medial prefrontal and posterior cingulate/medial parietal cortices together with pulvinar thalami, a network known to be effective in autobiographic memory retrieval and self......-awareness. Autobiographic memory retrieval of previous personal judgments of visually presented words was used as stimuli. It is demonstrated that the prestimulus condition is characterized by causal, recurrent oscillations which are maximal in the lower gamma range. When retrieving previous judgments of visually presented...

  5. Nested Hoare Triples and Frame Rules for Higher-order Store

    CERN Document Server

    Schwinghammer, Jan; Reus, Bernhard; Yang, Hongseok

    2011-01-01

    Separation logic is a Hoare-style logic for reasoning about programs with heap-allocated mutable data structures. As a step toward extending separation logic to high-level languages with ML-style general (higher-order) storage, we investigate the compatibility of nested Hoare triples with several variations of higher-order frame rules. The interaction of nested triples and frame rules can be subtle, and the inclusion of certain frame rules is in fact unsound. A particular combination of rules can be shown consistent by means of a Kripke model where worlds live in a recursively defined ultrametric space. The resulting logic allows us to elegantly prove programs involving stored code. In particular, using recursively defined assertions, it leads to natural specifications and proofs of invariants required for dealing with recursion through the store.

  6. Influence of higher order modes on the beam stability in the high power superconducting proton linac

    CERN Document Server

    Schuh, M; Gerigk, F; Tuckmantel, J

    2011-01-01

    Higher order modes (HOMs) can severely limit the operation of superconducting cavities in a linear accelerator with high beam current, high duty factor, and complex pulse structure. The full HOM spectrum has to be analyzed in order to identify potentially dangerous modes already during the design phase and to define their damping requirements. For this purpose a dedicated beam simulation code simulation of higher order mode dynamics (SMD) focused on beam-HOM interaction was developed, taking into account important effects like the HOM frequency spread, beam input jitter, different chopping patterns, as well as klystron and alignment errors. Here, SMD is used to investigate the influence of HOMs in detail in the superconducting proton linac at CERN and their potential to drive beam instabilities in the longitudinal and transverse plane.

  7. Influence of higher order modes on the beam stability in the high power superconducting proton linac

    Directory of Open Access Journals (Sweden)

    Marcel Schuh

    2011-05-01

    Full Text Available Higher order modes (HOMs can severely limit the operation of superconducting cavities in a linear accelerator with high beam current, high duty factor, and complex pulse structure. The full HOM spectrum has to be analyzed in order to identify potentially dangerous modes already during the design phase and to define their damping requirements. For this purpose a dedicated beam simulation code simulation of higher order mode dynamics (SMD focused on beam-HOM interaction was developed, taking into account important effects like the HOM frequency spread, beam input jitter, different chopping patterns, as well as klystron and alignment errors. Here, SMD is used to investigate the influence of HOMs in detail in the superconducting proton linac at CERN and their potential to drive beam instabilities in the longitudinal and transverse plane.

  8. Study of Higher Order Modes in Superconducting Accelerating Structures for Linac Applications

    CERN Document Server

    Schuh, Marcel; Welsch, C P

    2011-01-01

    Higher Order Modes (HOMs) can severely limit the operation of superconducting cavities in a linear accelerator with high beam current, high duty factor and complex pulse structure. Therefore, the full HOM spectrum has to be analysed in detail to identify potentially dangerous modes already during the design phase and to define their damping requirements. For this purpose a dedicated beam dynamics simulation code, Simulation of higher order Mode Dynamics (SMD), focusing on beam-HOM interaction, has been developed in the frame of this project. SMD allows to analyse the beam behaviour under the presence of HOMs, taking into account many important effects, such as for example the HOM frequency spread, beam input jitter, different chopping patterns, as well as klystron and alignment errors. SMD is used to investigate in detail into the effects of HOMs in the Superconducting Proton Linac (SPL) at CERN and in particular their potential to drive beam instabili- ties in the longitudinal and transverse direction. Based...

  9. On the Polarization of non-Guassian optical quantum field: higher-order optical-polarization

    CERN Document Server

    Singh, Ravi S

    2013-01-01

    Polarization of light signifies transversal, anisotropic and asymmetrical statistical property of electromagnetic radiation about direction of propagation. Traditionally, optical-polarization is characterized by Stokes theory susceptible to be insufficient in assessing polarization structure of optical quantum fields and, also, does not decipher twin characteristic polarization parameters (ratio of real amplitudes and difference in phases). An alternative way, in spirit of classical description of optical-polarization, is introduced which can be generalized to deal higher-order polarization of quantum light, particularly, prepared in non-Guassian Schrodinger Cat or Cat-like states and entangled bi-modal coherent states. On account of pseudo mono-modal or multi-modal nature of such optical quantum field, higher-order polarization is seen to be highly sensitive to the basis of description.

  10. Higher-order models versus direct hierarchical models: g as superordinate or breadth factor?

    Directory of Open Access Journals (Sweden)

    GILLES E. GIGNAC

    2008-03-01

    Full Text Available Intelligence research appears to have overwhelmingly endorsed a superordinate (higher-order model conceptualization of g, in comparison to the relatively less well-known breadth conceptualization of g, as represented by the direct hierarchical model. In this paper, several similarities and distinctions between the indirect and direct hierarchical models are delineated. Based on the re-analysis of five correlation matrices, it was demonstrated via CFA that the conventional conception of g as a higher-order superordinate factor was likely not as plausible as a first-order breadth factor. The results are discussed in light of theoretical advantages of conceptualizing g as a first-order factor. Further, because the associations between group-factors and g are constrained to zero within a direct hierarchical model, previous observations of isomorphic associations between a lower-order group factor and g are questioned.

  11. Study of (2+1)-Dimensional Higher-Order Broer-Kaup System

    Institute of Scientific and Technical Information of China (English)

    WANG Ling; LIU Xi-Qiang; DONG Zhong-Zhou

    2007-01-01

    Painlevé property and infinite symmetries of the (2+1)-dimensional higher-order Broer-Kaup (HBK) system are studied in this paper.Using the modified direct method,we derive the theorem of general symmetry groups to (2+1)-dimensional HBK system.Based on our theorem,some new forms of solutions are obtained.We also find infinite number of conservation laws of the (2+1)-dimensional HBK system.

  12. Generating dynamic higher-order Markov models in web usage mining

    OpenAIRE

    Borges, J; Levene, Mark

    2005-01-01

    Markov models have been widely used for modelling users’ web navigation behaviour. In previous work we have presented a dynamic clustering-based Markov model that accurately represents second-order transition probabilities given by a collection of navigation sessions. Herein, we propose a generalisation of the method that takes into account higher-order conditional probabilities. The method makes use of the state cloning concept together with a clustering technique to separate the navigation ...

  13. Towards a Theory of Bisimulation for the Higher-Order Process Calculi

    Institute of Scientific and Technical Information of China (English)

    Yong-JianLi; Xin-XinLiu

    2004-01-01

    In this paper, a labelled transition semantics for higher-order process calculi is studied. The labelled transition semantics is relatively clean and simple, and corresponding bisimulation equivalence can be easily formulated based on it. And the congruence properties of the bisimulation equivalence can be proved easily. To show the correspondence between the proposed semantics and the well-established ones, the bisimulation is characterized as a version of barbed equivalence and a version of context bisimulation.

  14. Towards a Theory of Bisimulation for the Higher-Order Process Calculi

    Institute of Scientific and Technical Information of China (English)

    Yong-Jian Li; Xin-Xin Liu

    2004-01-01

    In this paper, a labelled transition semantics for higher-order process calculi is studied. The labelled transition semantics is relatively clean and simple, and corresponding bisimulation equivalence can be easily formulated based on it. And the congruence properties of the bisimulation equivalence can be proved easily.To show the correspondence between the proposed semantics and the well-established ones, the bisimulation is characterized as a version of barbed equivalence and a version of context bisimulation.

  15. Numerical study of higher order analogues of the Tracy-Widom distribution

    CERN Document Server

    Claeys, Tom

    2011-01-01

    We study a family of distributions that arise in critical unitary random matrix ensembles. They are expressed as Fredholm determinants and describe the limiting distribution of the largest eigenvalue when the dimension of the random matrices tends to infinity. The family contains the Tracy-Widom distribution and higher order analogues of it. We compute the distributions numerically by solving a Riemann-Hilbert problem numerically, plot the distributions, and discuss several properties that they appear to exhibit.

  16. Analytical On-shell Calculation of Higher Order Scattering: Massive Particles

    CERN Document Server

    Holstein, Barry R

    2016-01-01

    We demonstrate that the use of on-shell methods, involving calculation of the discontinuity across the t-channel cut associated with the exchange of a pair of massless particles, can be used to evaluate loop contributions to both the electromagnetic and gravitational scattering of massive systems. In the gravitational case, the use of factorization permits a straightforward and algebraic calculation of higher order scattering results, which were obtained previously by much more arduous Feynman diagram techniques.

  17. Analytical On-shell Calculation of Higher Order Scattering: Massless Particles

    CERN Document Server

    Holstein, Barry R

    2016-01-01

    We demonstrate that the use of on-shell methods involving calculation of the discontinuity across the t-channel cut associated with the exchange of a pair of massless particles can be used to evaluate loop contributions to the electromagnetic and gravitational scattering of both massive and massless particles. In the gravitational case the use of factorization permits a straightforward and algebraic calculation of higher order scattering results, which were obtained previously by considerably more arduous Feynman diagram techniques.

  18. Goos-Hanchen shift for higher order Hermite-Gaussian beams

    OpenAIRE

    Golla, Dheeraj; Gupta, Subhasish Dutta

    2010-01-01

    We study the reflection of a Hermite-Gaussian beam at an interface between two dielectric media. We show that unlike Laguerre-Gaussian beams, Hermite-Gaussian beams undergo no significant distortion upon reflection. We report Goos-H\\"anchen shift for all the spots of a higher order Hermite Gaussian beam near the critical angle. The shift is shown to be insignificant away from the critical angle. The calculations are carried out neglecting the longitudinal component along the direction of prop...

  19. Higher Order Thinking in the Australian Army Suite of Logistic Officer Courses

    Science.gov (United States)

    2006-12-15

    Two will expand on this introduction by providing the reader with a literacy review of the concepts associated with higher order thinking and...Technology Literacy (1999) findings included “intellectual capabilities” as being critical to technological fluency, citing “engagement in sustained...some form of didactic , explicit, or direct instruction. On the other hand, if the focus is on procedural knowledge, it is likely that modeling and

  20. A higher order lattice BGK model for simulating some nonlinear partial differential equations

    Institute of Scientific and Technical Information of China (English)

    LAI HuiLin; MA ChangFeng

    2009-01-01

    In this paper, we consider a one-dimensional nonlinear partial differential equation that has the form ut + αuux+βunux-γuxx+δuxxx= F(U). A higher order lattice Bhatnager-Gross-Krook (BGK) model with an amending-function is proposed. With the Chapman-Enskog expansion, different kinds of nonlinear partial differential equations are recovered correctly from the continuous Boltzmann equation. The numerical results show that this method is very effective.