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Sample records for group theoretical approach

  1. A group theoretic approach to quantum information

    Hayashi, Masahito

    2017-01-01

    This textbook is the first one addressing quantum information from the viewpoint of group symmetry. Quantum systems have a group symmetrical structure. This structure enables to handle systematically quantum information processing. However, there is no other textbook focusing on group symmetry for quantum information although there exist many textbooks for group representation. After the mathematical preparation of quantum information, this book discusses quantum entanglement and its quantification by using group symmetry. Group symmetry drastically simplifies the calculation of several entanglement measures although their calculations are usually very difficult to handle. This book treats optimal information processes including quantum state estimation, quantum state cloning, estimation of group action and quantum channel etc. Usually it is very difficult to derive the optimal quantum information processes without asymptotic setting of these topics. However, group symmetry allows to derive these optimal solu...

  2. Group theoretic approaches to nuclear and hadronic collective motion

    Biedenharn, L.C.

    1982-01-01

    Three approaches to nuclear and hadronic collective motion are reviewed, compared and contrasted: the standard symmetry approach as typified by the Interacting Boson Model, the kinematic symmetry group approach of Gell-Mann and Tomonaga, and the recent direct construction by Buck. 50 references

  3. Group theoretic approaches to nuclear and hadronic collective motion

    Biedenharn, L.C.

    1982-01-01

    Three approaches to nuclear and hadronic collective motion are reviewed, compared and contrasted: the standard symmetry approach as typified by the Interacting Boson Model, the kinematic symmetry group approach of Gell-Mann and Tomonaga, and the recent direct construction by Buck. 50 references.

  4. Group-theoretical approach to relativistic eikonal physics

    Leon, J; Quiros, M [Instituto de Enstructura de la Materia, C.S.I.C., Madrid (Spain); Departamento de Matematica, Universidad Complutense, Campus de Alcala (Spain)); Ramirez Mittelbrunn, J [Instituto de Estructura de la Materia, C.S.I.C., Madrid (Spain)

    1977-09-01

    A contraction of the Poincare group is performed leading to the eikonal approximation. Invariants, one-particle states, spinning particles and some interaction problems are studied with the following results: momenta of ultrarelativistic particles behave as lightlike, the little group being E/sub 2/, spin behaves as that of zero-mass particles, helicity being conserved in the presence of interactions. The full eikonal results are rederived for Green's functions, wave functions, etc. The way for computing corrections due to transverse momenta and spin-dependent interactions is outlined. A parallel analysis is made for the infinite-momentum frame, the similarities and differences between this formalism and the eikonal approach being disclosed.

  5. Relativistic kinematics and dynamics: a new group theoretical approach

    Giovannini, N.

    1983-01-01

    The author reanalyzes the relationships between physical states and space-time symmetries with a view to describing relativistic extended and interacting systems. For this description he proposes to introduce, in space-time, an additional observable, related to a natural notion of simultaneity. The introduction of this new observable is justified on the basis of the operational meaning of the relations between state descriptions and symmetries in this case. The Poincare transformations are correspondingly split into two parts: the first one, kinematical, related to the symmetries of the description of the states, the other one, dynamical, related to the possible forms for the evolution. It is shown that the kinematical symmetries lead in a straightforward way to the expected classical and quantal state spaces for single particles of arbitrary spin and the author shows how the remaining symmetries can be related to the derivation of the possible forms for the dynamics. He finds as a particular case the usual dynamics of single particles in external fields (with some satisfactory improvements due to the corresponding new interpretation) and extends the method to the dynamics of N interacting particles. He also shows why this new approach and interpretation of relativistic states is necessary and how it allows a covariant description in the problems raised by the (recently measured) quantum correlations at-a-distance concerning the Einstein-Podolsky-Rosen paradox, something which seems quite impossible in the usual frameworks. (Auth.)

  6. Groups, matrices, and vector spaces a group theoretic approach to linear algebra

    Carrell, James B

    2017-01-01

    This unique text provides a geometric approach to group theory and linear algebra, bringing to light the interesting ways in which these subjects interact. Requiring few prerequisites beyond understanding the notion of a proof, the text aims to give students a strong foundation in both geometry and algebra. Starting with preliminaries (relations, elementary combinatorics, and induction), the book then proceeds to the core topics: the elements of the theory of groups and fields (Lagrange's Theorem, cosets, the complex numbers and the prime fields), matrix theory and matrix groups, determinants, vector spaces, linear mappings, eigentheory and diagonalization, Jordan decomposition and normal form, normal matrices, and quadratic forms. The final two chapters consist of a more intensive look at group theory, emphasizing orbit stabilizer methods, and an introduction to linear algebraic groups, which enriches the notion of a matrix group. Applications involving symm etry groups, determinants, linear coding theory ...

  7. The decays Psub(c) -> VP in the group theoretical and quark diagrammatic approaches

    Tuan, S.F.; Xiaoyuan Li.

    1983-08-01

    Decays of charmed meson into one vector meson and one pseudoscalar meson Psub(c) -> VP in both the group theoretical and quark diagrammatic approaches are considered. A complete decay amplitude analysis is given. The present available experimental data can be accomodated if the contributions from exotic final states and exotic piece of weak Hamiltonian are also taken into account. (orig.)

  8. A Group Theoretic Approach to Metaheuristic Local Search for Partitioning Problems

    2005-05-01

    Tabu Search. Mathematical and Computer Modeling 39: 599-616. 107 Daskin , M.S., E. Stern. 1981. A Hierarchical Objective Set Covering Model for EMS... A Group Theoretic Approach to Metaheuristic Local Search for Partitioning Problems by Gary W. Kinney Jr., B.G.S., M.S. Dissertation Presented to the...DISTRIBUTION STATEMENT A Approved for Public Release Distribution Unlimited The University of Texas at Austin May, 2005 20050504 002 REPORT

  9. Group theoretic approach for solving the problem of diffusion of a drug through a thin membrane

    Abd-El-Malek, Mina B.; Kassem, Magda M.; Meky, Mohammed L. M.

    2002-03-01

    The transformation group theoretic approach is applied to study the diffusion process of a drug through a skin-like membrane which tends to partially absorb the drug. Two cases are considered for the diffusion coefficient. The application of one parameter group reduces the number of independent variables by one, and consequently the partial differential equation governing the diffusion process with the boundary and initial conditions is transformed into an ordinary differential equation with the corresponding conditions. The obtained differential equation is solved numerically using the shooting method, and the results are illustrated graphically and in tables.

  10. Stress transfer from pile group in saturated and unsaturated soil using theoretical and experimental approaches

    al-Omari Raid R.

    2017-01-01

    Full Text Available Piles are often used in groups, and the behavior of pile groups under the applied loads is generally different from that of single pile due to the interaction of neighboring piles, therefore, one of the main objectives of this paper is to investigate the influence of pile group (bearing capacity, load transfer sharing for pile shaft and tip in comparison to that of single piles. Determination of the influence of load transfer from the pile group to the surrounding soil and the mechanism of this transfer with increasing the load increment on the tip and pile shaft for the soil in saturated and unsaturated state (when there is a negative pore water pressure. Different basic properties are used that is (S = 90%, γd = 15 kN / m3, S = 90%, γd = 17 kN / m3 and S = 60%, γd =15 kN / m3. Seven model piles were tested, these was: single pile (compression and pull out test, 2×1, 3×1, 2×2, 3×2 and 3×3 group. The stress was measured with 5 cm diameter soil pressure transducer positioned at a depth of 5 cm below the pile tip for all pile groups. The measured stresses below the pile tip using a soil pressure transducer positioned at a depth of 0.25L (where L is the pile length below the pile tip are compared with those calculated using theoretical and conventional approaches. These methods are: the conventional 2V:1H method and the method used the theory of elasticity. The results showed that the method of measuring the soil stresses with soil pressure transducer adopted in this study, gives in general, good results of stress transfer compared with the results obtained from the theoretical and conventional approaches.

  11. Perturbative Field-Theoretical Renormalization Group Approach to Driven-Dissipative Bose-Einstein Criticality

    Uwe C. Täuber

    2014-04-01

    Full Text Available The universal critical behavior of the driven-dissipative nonequilibrium Bose-Einstein condensation transition is investigated employing the field-theoretical renormalization group method. Such criticality may be realized in broad ranges of driven open systems on the interface of quantum optics and many-body physics, from exciton-polariton condensates to cold atomic gases. The starting point is a noisy and dissipative Gross-Pitaevski equation corresponding to a complex-valued Landau-Ginzburg functional, which captures the near critical nonequilibrium dynamics, and generalizes model A for classical relaxational dynamics with nonconserved order parameter. We confirm and further develop the physical picture previously established by means of a functional renormalization group study of this system. Complementing this earlier numerical analysis, we analytically compute the static and dynamical critical exponents at the condensation transition to lowest nontrivial order in the dimensional ε expansion about the upper critical dimension d_{c}=4 and establish the emergence of a novel universal scaling exponent associated with the nonequilibrium drive. We also discuss the corresponding situation for a conserved order parameter field, i.e., (subdiffusive model B with complex coefficients.

  12. Renormalization group-theoretic approach to electron localization in disordered systems

    Kumar, N.; Heinrichs, J.

    1977-06-01

    The localization problem for the Anderson tight-binding model with site-diagonal (gaussian) disorder is studied, using a previously established analogy between this problem and the statistical mechanics of a zero-component classical field. The equivalent free-energy functional turns out to have complex coefficients in the bilinear terms but involves a real repulsive quartic interaction. The averaged one-electron propagator corresponds to the two-point correlation function for the equivalent statistical problem and the critical point gives the mobility edge, which is identified with the (real) fixed point energy of the associated renormalization group. Since for convergence reasons the conventional perturbative treatment of Wilson's formula is invalid, it is resorted to a non-perturbative approach which leads to a physical fixed point corresponding to a repulsive quartic interaction. The results for the mobility edge in three dimensions and for the critical disorder for an Anderson transition in two dimensions agree well with previous detailed predictions. The critical indices describing the approach of the transition at the mobility edge of various physical quantities, within the epsilon-expansion are also discussed. The more general problem where both diagonal and off-diagonal disorder is present in the Anderson hamiltonian is considered. In this case it is shown that the Hamilton function for the equivalent zero-component classical field model involves an additional biquadratic exchange term. From a simple generalization of Wilson's recursion relation and its non-perturbative solution explicit expressions for the mobility edges for weak diagonal and off-diagonal disorder in two and three dimensions are obtained. Our treatment casts doubts on the validity of recent conclusions about electron localization based on the renormalization group study of the nm-component spin model

  13. Group theoretical approach to quantum fields in de Sitter space II. The complementary and discrete series

    Joung, Euihun; Mourad, Jihad; Parentani, Renaud

    2007-01-01

    We use an algebraic approach based on representations of de Sitter group to construct covariant quantum fields in arbitrary dimensions. We study the complementary and the discrete series which correspond to light and massless fields and which lead new feature with respect to the massive principal series we previously studied (hep-th/0606119). When considering the complementary series, we make use of a non-trivial scalar product in order to get local expressions in the position representation. Based on these, we construct a family of covariant canonical fields parametrized by SU(1, 1)/U(1). Each of these correspond to the dS invariant alpha-vacua. The behavior of the modes at asymptotic times brings another difficulty as it is incompatible with the usual definition of the in and out vacua. We propose a generalized notion of these vacua which reduces to the usual conformal vacuum in the conformally massless limit. When considering the massless discrete series we find that no covariant field obeys the canonical commutation relations. To further analyze this singular case, we consider the massless limit of the complementary scalar fields we previously found. We obtain canonical fields with a deformed representation by zero modes. The zero modes have a dS invariant vacuum with singular norm. We propose a regularization by a compactification of the scalar field and a dS invariant definition of the vertex operators. The resulting two-point functions are dS invariant and have a universal logarithmic infrared divergence

  14. A Theoretical Approach

    NICO

    L-rhamnose and L-fucose: A Theoretical Approach ... L-ramnose and L-fucose, by means of the Monte Carlo conformational search method. The energy of the conformers ..... which indicates an increased probability for the occurrence of.

  15. Comparing the group theoretical approaches to the description of dipole and quadrupole collectivity in nuclei

    Georgieva, A I

    2013-01-01

    The comparison of the two types of collectivity in nuclear dynamics is based on the equal realizations of their basic symmetries, represented by the algebra-chain u(3) superset of su(3) superset of so(3). We illustrate this on the example of two phenomenological algebraic models: the semimicroscopic algebraic cluster model (SACM) with one of the clusters considered as a scalar and the interacting two vector boson model (IVBM). In both of them the root group structure that leads to the above chain is based on the coupling of two different U(3) representations, with different physical interpretations. These similarities allow for the use of the same mathematical tools in building the theory, but there are important differences that come from the different higher symmetries in which this equal substructures are embedded.

  16. Open problems and results in the group theoretic approach to quantum gravity via the BMS group and its generalizations

    Melas, Evangelos

    2011-01-01

    The Bondi-Metzner-Sachs group B is the common asymptotic group of all asymptotically flat (lorentzian) space-times, and is the best candidate for the universal symmetry group of General Relativity. However, in quantum gravity, complexified or euclidean versions of General Relativity are frequently considered. McCarthy has shown that there are forty-two generalizations of B for these versions of the theory and a variety of further ones, either real in any signature, or complex. A firm foundation for quantum gravity can be laid by following through the analogue of Wigner's programme for special relativity with B replacing the Poincare group P. Here the main results which have been obtained so far in this research programme are reported and the more important open problems are stated.

  17. Theoretical Approaches to Coping

    Sofia Zyga

    2013-01-01

    Full Text Available Introduction: Dealing with stress requires conscious effort, it cannot be perceived as equal to individual's spontaneous reactions. The intentional management of stress must not be confused withdefense mechanisms. Coping differs from adjustment in that the latter is more general, has a broader meaning and includes diverse ways of facing a difficulty.Aim: An exploration of the definition of the term "coping", the function of the coping process as well as its differentiation from other similar meanings through a literature review.Methodology: Three theoretical approaches of coping are introduced; the psychoanalytic approach; approaching by characteristics; and the Lazarus and Folkman interactive model.Results: The strategic methods of the coping approaches are described and the article ends with a review of the approaches including the functioning of the stress-coping process , the classificationtypes of coping strategies in stress-inducing situations and with a criticism of coping approaches.Conclusions: The comparison of coping in different situations is difficult, if not impossible. The coping process is a slow process, so an individual may select one method of coping under one set ofcircumstances and a different strategy at some other time. Such selection of strategies takes place as the situation changes.

  18. Theoretical approaches to elections defining

    Natalya V. Lebedeva

    2011-01-01

    Theoretical approaches to elections defining develop the nature, essence and content of elections, help to determine their place and a role as one of the major national law institutions in democratic system.

  19. Theoretical approaches to elections defining

    Natalya V. Lebedeva

    2011-01-01

    Full Text Available Theoretical approaches to elections defining develop the nature, essence and content of elections, help to determine their place and a role as one of the major national law institutions in democratic system.

  20. Group theoretical methods in Physics

    Olmo, M.A. del; Santander, M.; Mateos Guilarte, J.M.

    1993-01-01

    The meeting had 102 papers. These was distributed in following areas: -Quantum groups,-Integrable systems,-Physical Applications of Group Theory,-Mathematical Results,-Geometry, Topology and Quantum Field Theory,-Super physics,-Super mathematics,-Atomic, Molecular and Condensed Matter Physics. Nuclear and Particle Physics,-Symmetry and Foundations of classical and Quantum mechanics

  1. Theoretical Approaches to Political Communication.

    Chesebro, James W.

    Political communication appears to be emerging as a theoretical and methodological academic area of research within both speech-communication and political science. Five complimentary approaches to political science (Machiavellian, iconic, ritualistic, confirmational, and dramatistic) may be viewed as a series of variations which emphasize the…

  2. Theoretical Issues in Clinical Social Group Work.

    Randall, Elizabeth; Wodarski, John S.

    1989-01-01

    Reviews relevant issues in clinical social group practice including group versus individual treatment, group work advantages, approach rationale, group conditions for change, worker role in group, group composition, group practice technique and method, time as group work dimension, pretherapy training, group therapy precautions, and group work…

  3. Theoretical Approaches to Nuclear Proliferation

    Konstantin S. Tarasov

    2015-01-01

    Full Text Available This article analyses discussions between representatives of three schools in the theory of international relations - realism, liberalism and constructivism - on the driving factors of nuclear proliferation. The paper examines major theoretical approaches, outlined in the studies of Russian and foreign scientists, to the causes of nuclear weapons development, while unveiling their advantages and limitations. Much of the article has been devoted to alternative approaches, particularly, the role of mathematical modeling in assessing proliferation risks. The analysis also reveals a variety of different approaches to nuclear weapons acquisition, as well as the absence of a comprehensive proliferation theory. Based on the research results the study uncovers major factors both favoring and impeding nuclear proliferation. The author shows that the lack of consensus between realists, liberals and constructivists on the nature of proliferation led a number of scientists to an attempt to explain nuclear rationale by drawing from the insights of more than one school in the theory of IR. Detailed study of the proliferation puzzle contributes to a greater understating of contemporary international realities, helps to identify mechanisms that are most likely to deter states from obtaining nuclear weapons and is of the outmost importance in predicting short- and long-term security environment. Furthermore, analysis of the existing scientific literature on nuclear proliferation helps to determine future research agenda of the subject at hand.

  4. Theoretical Approaches to Lignin Chemistry

    Shevchenko, Sergey M.

    1994-01-01

    A critical review is presented of the applications of theoretical methods to the studies of the structure and chemical reactivity of lignin, including simulation of macromolecular properties, conformational calculations, quantum chemical analyses of electronic structure, spectra and chemical reactivity. Modern concepts of spatial organization and chemical reactivity of lignins are discussed.

  5. Machine learning a theoretical approach

    Natarajan, Balas K

    2014-01-01

    This is the first comprehensive introduction to computational learning theory. The author's uniform presentation of fundamental results and their applications offers AI researchers a theoretical perspective on the problems they study. The book presents tools for the analysis of probabilistic models of learning, tools that crisply classify what is and is not efficiently learnable. After a general introduction to Valiant's PAC paradigm and the important notion of the Vapnik-Chervonenkis dimension, the author explores specific topics such as finite automata and neural networks. The presentation

  6. Group theoretical quantization of isotropic loop cosmology

    Livine, Etera R.; Martín-Benito, Mercedes

    2012-06-01

    We achieve a group theoretical quantization of the flat Friedmann-Robertson-Walker model coupled to a massless scalar field adopting the improved dynamics of loop quantum cosmology. Deparemetrizing the system using the scalar field as internal time, we first identify a complete set of phase space observables whose Poisson algebra is isomorphic to the su(1,1) Lie algebra. It is generated by the volume observable and the Hamiltonian. These observables describe faithfully the regularized phase space underlying the loop quantization: they account for the polymerization of the variable conjugate to the volume and for the existence of a kinematical nonvanishing minimum volume. Since the Hamiltonian is an element in the su(1,1) Lie algebra, the dynamics is now implemented as SU(1, 1) transformations. At the quantum level, the system is quantized as a timelike irreducible representation of the group SU(1, 1). These representations are labeled by a half-integer spin, which gives the minimal volume. They provide superselection sectors without quantization anomalies and no factor ordering ambiguity arises when representing the Hamiltonian. We then explicitly construct SU(1, 1) coherent states to study the quantum evolution. They not only provide semiclassical states but truly dynamical coherent states. Their use further clarifies the nature of the bounce that resolves the big bang singularity.

  7. Special functions group theoretical aspects and applications

    Schempp, Walter; Askey, Richard A

    1984-01-01

    Approach your problems from It isn't that they can't see the right end and begin with the solution. the answers. Then one day, It is that they can't see the perhaps you will find the problem. final question. G.K. Chesterton. The Scandal 'The Hermit Clad in Crane of Father Brown 'The Point of Feathers' in R. van Gulik's a Pin'. The Chinese Maze Murders. Growing specialization and diversification have brought a host of monographs and textbooks on increasingly specialized topics. However, the "tree" of knowledge of mathematics and related fields does not grow only by putting forth new branches. It also happens, quite often in fact, that branches which were thought to be completely disparate are suddenly seen to be related. Further, the kind and level of sophistication of mathematics applied in various sciences has changed drastically in recent years: measure theory is used (non-trivially) in regional and theoretical economics; algebraic geometry interacts with physics; the Minkowsky lemma, coding theory and the ...

  8. Managerial Leadership - A Theoretical Approach

    Felicia Cornelia MACARIE

    2007-06-01

    Full Text Available The paper endeavors to offer an overview of the major theories on leadership and the way in which it influences the management of contemporary organizations. Numerous scholars highlight that there are numerous overlaps between the concepts of management and leadership. This is the reason why the first section of the paper focuses on providing an extensive overview of the literature regarding the meaning of the two aforementioned concepts. The second section addresses more in depth the concept of leadership and managerial leadership and focuses on the ideal profile of the leader. The last section of the paper critically discusses various types of leadership and more specifically modern approaches to the concept and practices of leadership.

  9. Set-Theoretic Approach to Maturity Models

    Lasrado, Lester Allan

    Despite being widely accepted and applied, maturity models in Information Systems (IS) have been criticized for the lack of theoretical grounding, methodological rigor, empirical validations, and ignorance of multiple and non-linear paths to maturity. This PhD thesis focuses on addressing...... these criticisms by incorporating recent developments in configuration theory, in particular application of set-theoretic approaches. The aim is to show the potential of employing a set-theoretic approach for maturity model research and empirically demonstrating equifinal paths to maturity. Specifically...... methodological guidelines consisting of detailed procedures to systematically apply set theoretic approaches for maturity model research and provides demonstrations of it application on three datasets. The thesis is a collection of six research papers that are written in a sequential manner. The first paper...

  10. A Set Theoretical Approach to Maturity Models

    Lasrado, Lester; Vatrapu, Ravi; Andersen, Kim Normann

    2016-01-01

    characterized by equifinality, multiple conjunctural causation, and case diversity. We prescribe methodological guidelines consisting of a six-step procedure to systematically apply set theoretic methods to conceptualize, develop, and empirically derive maturity models and provide a demonstration......Maturity Model research in IS has been criticized for the lack of theoretical grounding, methodological rigor, empirical validations, and ignorance of multiple and non-linear paths to maturity. To address these criticisms, this paper proposes a novel set-theoretical approach to maturity models...

  11. Game theoretic approaches for spectrum redistribution

    Wu, Fan

    2014-01-01

    This brief examines issues of spectrum allocation for the limited resources of radio spectrum. It uses a game-theoretic perspective, in which the nodes in the wireless network are rational and always pursue their own objectives. It provides a systematic study of the approaches that can guarantee the system's convergence at an equilibrium state, in which the system performance is optimal or sub-optimal. The author provides a short tutorial on game theory, explains game-theoretic channel allocation in clique and in multi-hop wireless networks and explores challenges in designing game-theoretic m

  12. Renormalization Group in different fields of theoretical physics

    Shirkov, D.V.

    1992-02-01

    A very simple and general approach to the symmetry that is widely known as a Renormalization Group symmetry is presented. It essentially uses a functional formulation of group transformations that can be considered as a generalization of self-similarity transformations well known in mathematical physics since last century. This generalized Functional Self-Similarity symmetry and corresponding group transformations are discussed first for a number of simple physical problems taken from diverse fields of classical physics as well as for QED. Then we formulate the Renorm-Group Method as a regular procedure that essentially improves the approximate solutions near the singularity. After that we discuss relations between different formulations of Renormalization Group as they appear in various parts of a modern theoretical physics. Finally we present several topics of RGM application in modern QFT. (author)

  13. Partial discharge transients: The field theoretical approach

    McAllister, Iain Wilson; Crichton, George C

    1998-01-01

    Up until the mid-1980s the theory of partial discharge transients was essentially static. This situation had arisen because of the fixation with the concept of void capacitance and the use of circuit theory to address what is in essence a field problem. Pedersen rejected this approach and instead...... began to apply field theory to the problem of partial discharge transients. In the present paper, the contributions of Pedersen using the field theoretical approach will be reviewed and discussed....

  14. New Theoretical Approach Integrated Education and Technology

    Ding, Gang

    2010-01-01

    The paper focuses on exploring new theoretical approach in education with development of online learning technology, from e-learning to u-learning and virtual reality technology, and points out possibilities such as constructing a new teaching ecological system, ubiquitous educational awareness with ubiquitous technology, and changing the…

  15. Group theoretical classification of chemical elements

    Byakov, V.M.; Kulakov, V.I.; Rumer, Y.B.; Fet, A.L.

    1977-01-01

    The method of classification of chemical elements, based on group symmetry principles, is compared with element properties. Elements are considered to be states of a single quantum system, the atomic structure being ignored. Elements treated as states of the system, break down into successively diminishing subsystems, big and small multiplets. The theory, being a group classification, does not describe in detail any of element properties, but leads to a unified qualitative description of all of them simultaneously

  16. Radiotherapy problem under fuzzy theoretic approach

    Ammar, E.E.; Hussein, M.L.

    2003-01-01

    A fuzzy set theoretic approach is used for radiotherapy problem. The problem is faced with two goals: the first is to maximize the fraction of surviving normal cells and the second is to minimize the fraction of surviving tumor cells. The theory of fuzzy sets has been employed to formulate and solve the problem. A linguistic variable approach is used for treating the first goal. The solutions obtained by the modified approach are always efficient and best compromise. A sensitivity analysis of the solutions to the differential weights is given

  17. Theoretical progress at CNDC theory group

    Lu Zhongdao

    1993-01-01

    In 1992, CNDC (Chinese Nuclear Data Center) theory group has made progress in model study, code making and data calculations for low energy nuclear reaction, intermediate and high energy nuclear reaction. It has also made progress in parameter library establishment. The brief explanations are presented

  18. Family Group Conferencing: A Theoretical Underpinning

    Metze, R.N.; Abma, T.A.; Kwekkeboom, R.H.

    2015-01-01

    In the last decade, Family Group Conferences (FGCs) have increasingly been used to help people and their networks deal with their problems. The FGC fits well with the call for equal rights and self-management coming from clients and client movements, as well as the economy-driven pressure towards

  19. Group theoretic derivation of angular functions for the non-relativistic A-body problem in the K-harmonics approach

    Alcaras, J.A.C.; Ferreira, J.L.

    1975-01-01

    A derivation of an angular basis for the A-body problem, suitable for the K-harmonics method, is presented. Those angular functions are obtained from homogeneous and harmonic polynomials, which are completely specified by labels associated to eigenvalues of the Casimir invariants of subgroups of the 3(A-1)-dimensional orthogonal group, among them, the total angular momentum and its z-projection [pt

  20. Theoretical and methodological approaches in discourse analysis.

    Stevenson, Chris

    2004-01-01

    Discourse analysis (DA) embodies two main approaches: Foucauldian DA and radical social constructionist DA. Both are underpinned by social constructionism to a lesser or greater extent. Social constructionism has contested areas in relation to power, embodiment, and materialism, although Foucauldian DA does focus on the issue of power Embodiment and materialism may be especially relevant for researchers of nursing where the physical body is prominent. However, the contested nature of social constructionism allows a fusion of theoretical and methodological approaches tailored to a specific research interest. In this paper, Chris Stevenson suggests a framework for working out and declaring the DA approach to be taken in relation to a research area, as well as to aid anticipating methodological critique. Method, validity, reliability and scholarship are discussed from within a discourse analytic frame of reference.

  1. Theoretical and methodological approaches in discourse analysis.

    Stevenson, Chris

    2004-10-01

    Discourse analysis (DA) embodies two main approaches: Foucauldian DA and radical social constructionist DA. Both are underpinned by social constructionism to a lesser or greater extent. Social constructionism has contested areas in relation to power, embodiment, and materialism, although Foucauldian DA does focus on the issue of power. Embodiment and materialism may be especially relevant for researchers of nursing where the physical body is prominent. However, the contested nature of social constructionism allows a fusion of theoretical and methodological approaches tailored to a specific research interest. In this paper, Chris Stevenson suggests a frame- work for working out and declaring the DA approach to be taken in relation to a research area, as well as to aid anticipating methodological critique. Method, validity, reliability and scholarship are discussed from within a discourse analytic frame of reference.

  2. A gauge-theoretic approach to gravity.

    Krasnov, Kirill

    2012-08-08

    Einstein's general relativity (GR) is a dynamical theory of the space-time metric. We describe an approach in which GR becomes an SU(2) gauge theory. We start at the linearized level and show how a gauge-theoretic Lagrangian for non-interacting massless spin two particles (gravitons) takes a much more simple and compact form than in the standard metric description. Moreover, in contrast to the GR situation, the gauge theory Lagrangian is convex. We then proceed with a formulation of the full nonlinear theory. The equivalence to the metric-based GR holds only at the level of solutions of the field equations, that is, on-shell. The gauge-theoretic approach also makes it clear that GR is not the only interacting theory of massless spin two particles, in spite of the GR uniqueness theorems available in the metric description. Thus, there is an infinite-parameter class of gravity theories all describing just two propagating polarizations of the graviton. We describe how matter can be coupled to gravity in this formulation and, in particular, how both the gravity and Yang-Mills arise as sectors of a general diffeomorphism-invariant gauge theory. We finish by outlining a possible scenario of the ultraviolet completion of quantum gravity within this approach.

  3. A sign-theoretic approach to biotechnology

    Bruni, Luis Emilio

    ” semiotic networks across hierarchical levels and for relating the different emergent codes in living systems. I consider this an important part of the work because there I define some of the main concepts that will help me to analyse different codes and semiotic processes in living systems in order...... to exemplify what is the relevance of a sign-theoretic approach to biotechnology. In particular, I introduce the notion of digital-analogical consensus as a semiotic pattern for the creation of complex logical products that constitute specific signs. The chapter ends with some examples of conspicuous semiotic...... to exemplify how a semiotic approach can be of help when organising the knowledge that can lead us to understanding the relevance, the role and the position of signal transduction networks in relation to the larger semiotic networks in which they function, i.e.: in the hierarchical formal processes of mapping...

  4. Quantum Computing: a Quantum Group Approach

    Wang, Zhenghan

    2013-01-01

    There is compelling theoretical evidence that quantum physics will change the face of information science. Exciting progress has been made during the last two decades towards the building of a large scale quantum computer. A quantum group approach stands out as a promising route to this holy grail, and provides hope that we may have quantum computers in our future.

  5. 31st International Colloquium in Group Theoretical Methods in Physics

    Gazeau, Jean-Pierre; Faci, Sofiane; Micklitz, Tobias; Scherer, Ricardo; Toppan, Francesco

    2017-01-01

    This proceedings records the 31st International Colloquium on Group Theoretical Methods in Physics (“Group 31”). Plenary-invited articles propose new approaches to the moduli spaces in gauge theories (V. Pestun, 2016 Weyl Prize Awardee), the phenomenology of neutrinos in non-commutative space-time, the use of Hardy spaces in quantum physics, contradictions in the use of statistical methods on complex systems, and alternative models of supersymmetry. This volume’s survey articles broaden the colloquia’s scope out into Majorana neutrino behavior, the dynamics of radiating charges, statistical pattern recognition of amino acids, and a variety of applications of gauge theory, among others. This year’s proceedings further honors Bertram Kostant (2016 Wigner Medalist), as well as S.T. Ali and L. Boyle, for their life-long contributions to the math and physics communities. The aim of the ICGTMP is to provide a forum for physicists, mathematicians, and scientists of related disciplines who develop or apply ...

  6. Recent Theoretical Approaches to Minimal Artificial Cells

    Fabio Mavelli

    2014-05-01

    Full Text Available Minimal artificial cells (MACs are self-assembled chemical systems able to mimic the behavior of living cells at a minimal level, i.e. to exhibit self-maintenance, self-reproduction and the capability of evolution. The bottom-up approach to the construction of MACs is mainly based on the encapsulation of chemical reacting systems inside lipid vesicles, i.e. chemical systems enclosed (compartmentalized by a double-layered lipid membrane. Several researchers are currently interested in synthesizing such simple cellular models for biotechnological purposes or for investigating origin of life scenarios. Within this context, the properties of lipid vesicles (e.g., their stability, permeability, growth dynamics, potential to host reactions or undergo division processes… play a central role, in combination with the dynamics of the encapsulated chemical or biochemical networks. Thus, from a theoretical standpoint, it is very important to develop kinetic equations in order to explore first—and specify later—the conditions that allow the robust implementation of these complex chemically reacting systems, as well as their controlled reproduction. Due to being compartmentalized in small volumes, the population of reacting molecules can be very low in terms of the number of molecules and therefore their behavior becomes highly affected by stochastic effects both in the time course of reactions and in occupancy distribution among the vesicle population. In this short review we report our mathematical approaches to model artificial cell systems in this complex scenario by giving a summary of three recent simulations studies on the topic of primitive cell (protocell systems.

  7. Theoretical approaches to social innovation – A critical literature review

    Butzin, A.; Davis, A.; Domanski, D.; Dhondt, S.; Howaldt, J.; Kaletka, C.; Kesselring, A.; Kopp, R.; Millard, J.; Oeij, P.; Rehfeld, D.; Schaper-Rinkel, P.; Schwartz, M.; Scoppetta, A.; Wagner-Luptacik, P.; Weber, M.

    2014-01-01

    The SI-DRIVE report “Theoretical approaches to Social Innovation – A Critical Literature Review” delivers a comprehensive overview on the state of the art of theoretically relevant building blocks for advancing a theoretical understanding of social innovation. It collects different theoretical

  8. Group theoretical methods and wavelet theory: coorbit theory and applications

    Feichtinger, Hans G.

    2013-05-01

    Before the invention of orthogonal wavelet systems by Yves Meyer1 in 1986 Gabor expansions (viewed as discretized inversion of the Short-Time Fourier Transform2 using the overlap and add OLA) and (what is now perceived as) wavelet expansions have been treated more or less at an equal footing. The famous paper on painless expansions by Daubechies, Grossman and Meyer3 is a good example for this situation. The description of atomic decompositions for functions in modulation spaces4 (including the classical Sobolev spaces) given by the author5 was directly modeled according to the corresponding atomic characterizations by Frazier and Jawerth,6, 7 more or less with the idea of replacing the dyadic partitions of unity of the Fourier transform side by uniform partitions of unity (so-called BUPU's, first named as such in the early work on Wiener-type spaces by the author in 19808). Watching the literature in the subsequent two decades one can observe that the interest in wavelets "took over", because it became possible to construct orthonormal wavelet systems with compact support and of any given degree of smoothness,9 while in contrast the Balian-Low theorem is prohibiting the existence of corresponding Gabor orthonormal bases, even in the multi-dimensional case and for general symplectic lattices.10 It is an interesting historical fact that* his construction of band-limited orthonormal wavelets (the Meyer wavelet, see11) grew out of an attempt to prove the impossibility of the existence of such systems, and the final insight was that it was not impossible to have such systems, and in fact quite a variety of orthonormal wavelet system can be constructed as we know by now. Meanwhile it is established wisdom that wavelet theory and time-frequency analysis are two different ways of decomposing signals in orthogonal resp. non-orthogonal ways. The unifying theory, covering both cases, distilling from these two situations the common group theoretical background lead to the

  9. Group-Theoretical Revision of the Unruh Effect

    Calixto, M; Perez-Romero, E; Aldaya, V

    2011-01-01

    We revise the Unruh effect (vacuum radiation in uniformly relativistic accelerated frames) in a group-theoretical setting by constructing a conformal SO(4,2)-invariant quantum field theory and its spontaneous breakdown when selecting Poincare invariant degenerated vacua (namely, coherent states of conformal zero modes). Special conformal transformations (accelerations) destabilize the Poincare vacuum and make it to radiate.

  10. Group-Theoretical Revision of the Unruh Effect

    Calixto, M [Departamento de Matematica Aplicada y Estadistica, Universidad Politecnica de Cartagena, Paseo Alfonso XIII 56, 30203 Cartagena (Spain); Perez-Romero, E; Aldaya, V, E-mail: Manuel.Calixto@upct.es [Instituto de Astrofisica de Andalucia (IAA-CSIC), Apartado Postal 3004, 18080 Granada (Spain)

    2011-03-01

    We revise the Unruh effect (vacuum radiation in uniformly relativistic accelerated frames) in a group-theoretical setting by constructing a conformal SO(4,2)-invariant quantum field theory and its spontaneous breakdown when selecting Poincare invariant degenerated vacua (namely, coherent states of conformal zero modes). Special conformal transformations (accelerations) destabilize the Poincare vacuum and make it to radiate.

  11. MEDIATIC NARRATIVES AND IDENTIFICATION PROCESSES. A THEORETICAL AND METHODOLOGICAL APPROACH

    Salomé Sola Morales

    2013-04-01

    Full Text Available This article, theoretical and argumentative, lays the conceptual and methodological basis for the study of the link between identity and narrative media identification processes undertaken by individuals and groups. Thus, the setting national identifications, professional, religious or gender is here proposed as the result of the dialectic between the 'media narrative identity', which the media produce and convey, and identification processes that individuals and groups perform. Furthermore we propose the use of the biographical method as a form of empirical approach to psycho-social phenomenon

  12. Choice Shifts in Groups: A Decision-Theoretic Basis

    Kfir Eliaz; Debraj Ray; Ronny Razin

    2006-01-01

    The phenomenon of choice shifts in group decision-making has received attention in the social psychology literature. Faced with a risky group decision, individuals appear to support more extreme choices relative to those they would make on their own. This paper demonstrates that from a decision-theoretic perspective, choice shifts are intimately connected to failures of expected utility theory. In the model studied here, the Allais paradox is equivalent to a well-studied configuration of choi...

  13. An attempt of classification of theoretical approaches to national identity

    Milošević-Đorđević Jasna S.

    2003-01-01

    Full Text Available It is compulsory that complex social concepts should be defined in different ways and approached from the perspective of different science disciplines. Therefore, it is difficult to precisely define them without overlapping of meaning with other similar concepts. This paper has made an attempt towards theoretical classification of the national identity and differentiate that concept in comparison to the other related concepts (race, ethnic group, nation, national background, authoritativeness, patriarchy. Theoretical assessments are classified into two groups: ones that are dealing with nature of national identity and others that are stating one or more dimensions of national identity, crucial for its determination. On the contrary to the primordialistic concept of national identity, describing it as a fundamental, deeply rooted human feature, there are many numerous contemporary theoretical approaches (instrumentalist, constructivist, functionalistic, emphasizing changeable, fluid, instrumentalist function of the national identity. Fundamental determinants of national identity are: language, culture (music, traditional myths, state symbols (territory, citizenship, self-categorization, religion, set of personal characteristics and values.

  14. Child Language Acquisition: Contrasting Theoretical Approaches

    Ambridge, Ben; Lieven, Elena V. M.

    2011-01-01

    Is children's language acquisition based on innate linguistic structures or built from cognitive and communicative skills? This book summarises the major theoretical debates in all of the core domains of child language acquisition research (phonology, word-learning, inflectional morphology, syntax and binding) and includes a complete introduction…

  15. A game theoretic approach to assignment problems

    Klijn, F.

    2000-01-01

    Game theory deals with the mathematical modeling and analysis of conflict and cooperation in the interaction of multiple decision makers. This thesis adopts two game theoretic methods to analyze a range of assignment problems that arise in various economic situations. The first method has as

  16. Game Theoretical Approach to Supply Chain Microfinance

    Sim , Jaehun; Prabhu , Vittaldas ,

    2013-01-01

    Part 1: Sustainable Production; International audience; This paper considers a supply chain microfinance model in which a manufacturer acts as a lender and a raw material supplier as a borrower. Using a game theoretical analysis, the study investigates how investment levels, raw material prices, and profit margins are influenced by loan interest rates under two types of decentralized channel policies: manufacturer Stackelberg and vertical Nash game. In addition, the study shows how the profit...

  17. UNCERTAINTY IN NEOCLASSICAL AND KEYNESIAN THEORETICAL APPROACHES: A BEHAVIOURAL PERSPECTIVE

    Sinziana BALTATESCU

    2015-11-01

    Full Text Available The ”mainstream” neoclassical assumptions about human economic behavior are currently challenged by both behavioural researches on human behaviour and other theoretical approaches which, in the context of the recent economic and financial crisis find arguments to reinforce their theoretical statements. The neoclassical “perfect rationality” assumption is most criticized and provokes the mainstream theoretical approach to efforts of revisiting the theoretical framework in order to re-state the economic models validity. Uncertainty seems, in this context, to be the concept that allows other theoretical approaches to take into consideration a more realistic individual from the psychological perspective. This paper is trying to present a comparison between the neoclassical and Keynesian approach of the uncertainty, considering the behavioural arguments and challenges addressed to the mainstream theory.

  18. Group theoretic reduction of Laplacian dynamical problems on fractal lattices

    Schwalm, W.A.; Schwalm, M.K.; Giona, M.

    1997-01-01

    Discrete forms of the Schroedinger equation, the diffusion equation, the linearized Landau-Ginzburg equation, and discrete models for vibrations and spin dynamics belong to a class of Laplacian-based finite difference models. Real-space renormalization of such models on finitely ramified regular fractals is known to give exact recursion relations. It is shown that these recursions commute with Lie groups representing continuous symmetries of the discrete models. Each such symmetry reduces the order of the renormalization recursions by one, resulting in a system of recursions with one fewer variable. Group trajectories are obtained from inverse images of fixed and invariant sets of the recursions. A subset of the Laplacian finite difference models can be mapped by change of boundary conditions and time dependence to a diffusion problem with closed boundaries. In such cases conservation of mass simplifies the group flow and obtaining the groups becomes easier. To illustrate this, the renormalization recursions for Green functions on four standard examples are decoupled. The examples are (1) the linear chain, (2) an anisotropic version of Dhar close-quote s 3-simplex, similar to a model dealt with by Hood and Southern, (3) the fourfold coordinated Sierpiacute nski lattice of Rammal and of Domany et al., and (4) a form of the Vicsek lattice. Prospects for applying the group theoretic method to more general dynamical systems are discussed. copyright 1997 The American Physical Society

  19. THE NETWORKS IN TOURISM: A THEORETICAL APPROACH

    Maria TĂTĂRUȘANU

    2016-12-01

    Full Text Available The economic world in which tourism companies act today is in a continuous changing process. The most important factor of these changes is the globalization of their environment, both in economic, social, natural and cultural aspects. The tourism companies can benefit from the opportunities brought by globalization, but also could be menaced by the new context. How could react the companies to these changes in order to create and maintain long term competitive advantage for their business? In the present paper we make a literature review of the new tourism companies´ business approach: the networks - a result and/or a reason for exploiting the opportunities or, on the contrary, for keeping their actual position on the market. It’s a qualitative approach and the research methods used are analyses, synthesis, abstraction, which are considered the most appropriate to achieve the objective of the paper.

  20. Theoretical approach to the scanning tunneling microscope

    Noguera, C.

    1990-01-01

    Within a one-electron approach, based on a Green's-function formalism, a nonperturbative expression for the tunneling current is obtained and used to discuss which spectroscopic information may be deduced from a scanning-tunneling-microscope experiment. It is shown up to which limits the voltage dependence of the tunneling current reproduces the local density of states at the surface, and how the reflection coefficients of the electronic waves at the surface may modify it

  1. Group theoretical analysis of octahedral tilting in perovskites

    Howard, C.J.; Stokes, H.T.

    1998-01-01

    Full text: Structures of the perovskite family, ABX 3 , have interested crystallographers over many years, and continue to attract attention on account of their fascinating electrical and magnetic properties, for example the giant magnetoresistive effects exhibited by certain perovskite materials. The ideal perovskite (cubic, space group Pm -/3 m) is a particularly simple structure, but also a demanding one, since aside from the lattice parameter there are no variable parameters in the structure. Consequently, the majority of perovskite structures are distorted perovskites (hettotypes), the most common distortion being the corner-linked tilting of the practically rigid BX 6 octahedral units. In this work, group theoretical methods have been applied to the study of octahedral tilting in perovskites. The only irreducible representations of the parent group (Pm -/3 m) which produce octahedral tilting subject to corner-linking constraints are M + / 3 and R 4 ' + . A six-dimensional order parameter in the reducible representation space of M + / 3 + R + / 4 describes the different possible tilting patterns. The space groups for the different perovskites are then simply the isotropy subgroups, comprising those operations which leave the order parameter invariant. The isotropy subgroups are obtained from a computer program or tabulations. The analysis yields a list of fifteen possible space groups for perovskites derived through octahedral tilting. A connection is made to the (twenty-three) tilt systems given previously by Glazer. The group-subgroup relationships have been derived and displayed. It is interesting to note that all known perovskites based on octahedral tilting conform with the fifteen space groups on our list, with the exception of one perovskite at high temperature, the structure of which seems poorly determined

  2. MEDICAL BRAIN DRAIN - A THEORETICAL APPROACH

    Boncea Irina

    2013-07-01

    Full Text Available Medical brain drain is defined as the migration of health personnel from developing countries to developed countries and between industrialized nations in search for better opportunities. This phenomenon became a global growing concern due to its impact on both the donor and the destination countries. This article aims to present the main theoretical contributions starting from 1950 until today and the historical evolution, in the attempt of correlating the particular case of medical brain drain with the theory and evolution of the brain drain in general. This article raises questions and offers answers, identifies the main issues and looks for possible solutions in order to reduce the emigration of medical doctors. Factors of influence include push (low level of income, poor working conditions, the absence of job openings and social recognition, oppressive political climate and pull (better remuneration and working conditions, prospects for career development, job satisfaction, security factors. Developing countries are confronting with the loss of their most valuable intellectuals and the investment in their education, at the benefit of developed nations. An ethical debate arises as the disparities between countries increases, industrialized nations filling in the gaps in health systems with professionals from countries already facing shortages. However, recent literature emphasizes the possibility of a “beneficial brain drain” through education incentives offered by the emigration prospects. Other sources of “brain gain” for donor country are the remittances, the scientific networks and return migration. Measures to stem the medical brain drain involve the common effort and collaboration between developing and developed countries and international organizations. Measures adopted by donor countries include higher salaries, better working conditions, security, career opportunities, incentives to stimulate return migration. Destination

  3. The dynamics of alliances. A game theoretical approach

    Ridder, A. de

    2007-01-01

    In this dissertation, Annelies de Ridder presents a game theoretical approach to strategic alliances. More specifically, the dynamics of and within alliances have been studied. To do so, four new models have been developed in the game theoretical tradition. Both coalition theory and strategic game

  4. Social representations: a theoretical approach in health

    Isaiane Santos Bittencourt

    2011-03-01

    Full Text Available Objective: To present the theory of social representations, placing its epistemology and knowing the basic concepts of its approach as a structural unit of knowledge for health studies. Justification: The use of this theory comes from the need to understand social eventsunder the lens of the meanings constructed by the community. Data Synthesis: This was a descriptive study of literature review, which used as a source of data collection the classical authors of social representations supported by articles from electronic search at Virtual Health Library (VHL. The definition and discussion of collected data enabled to introduce two themes, versed on the history and epistemology of representations and on the structuralapproach of representations in health studies. Conclusion: This review allowed highlight the importance of locating the objects of study with regard to contextual issues of individual and collective histories, valuing the plurality of relations, to come closer to reality that is represented by the subjects.

  5. Computational and Game-Theoretic Approaches for Modeling Bounded Rationality

    L. Waltman (Ludo)

    2011-01-01

    textabstractThis thesis studies various computational and game-theoretic approaches to economic modeling. Unlike traditional approaches to economic modeling, the approaches studied in this thesis do not rely on the assumption that economic agents behave in a fully rational way. Instead, economic

  6. A relevance theoretic approach to intertextuality in print advertising

    Anonymous vs. acknowledged intertexts: A relevance theoretic approach to intertextuality in print advertising. ... make intertextual references to texts from mass media genres other than advertising as part of an ... AJOL African Journals Online.

  7. Theoretical approaches to lightness and perception.

    Gilchrist, Alan

    2015-01-01

    . Evidence for and against these approaches is reviewed.

  8. Dramaturgical and Music-Theoretical Approaches to Improvisation Pedagogy

    Huovinen, Erkki; Tenkanen, Atte; Kuusinen, Vesa-Pekka

    2011-01-01

    The aim of this article is to assess the relative merits of two approaches to teaching musical improvisation: a music-theoretical approach, focusing on chords and scales, and a "dramaturgical" one, emphasizing questions of balance, variation and tension. Adult students of music pedagogy, with limited previous experience in improvisation,…

  9. Preservation of Newspapers: Theoretical Approaches and Practical Achievements

    Hasenay, Damir; Krtalic, Maja

    2010-01-01

    The preservation of newspapers is the main topic of this paper. A theoretical overview of newspaper preservation is given, with an emphasis on the importance of a systematic and comprehensive approach. Efficient newspaper preservation implies understanding the meaning of preservation in general, as well as understanding specific approaches,…

  10. One-dimensional barcode reading: an information theoretic approach

    Houni, Karim; Sawaya, Wadih; Delignon, Yves

    2008-03-01

    In the convergence context of identification technology and information-data transmission, the barcode found its place as the simplest and the most pervasive solution for new uses, especially within mobile commerce, bringing youth to this long-lived technology. From a communication theory point of view, a barcode is a singular coding based on a graphical representation of the information to be transmitted. We present an information theoretic approach for 1D image-based barcode reading analysis. With a barcode facing the camera, distortions and acquisition are modeled as a communication channel. The performance of the system is evaluated by means of the average mutual information quantity. On the basis of this theoretical criterion for a reliable transmission, we introduce two new measures: the theoretical depth of field and the theoretical resolution. Simulations illustrate the gain of this approach.

  11. Molecular approach of uranyl/mineral surfaces: theoretical approach

    Roques, J.

    2009-01-01

    As migration of radio-toxic elements through the geosphere is one of the processes which may affect the safety of a radioactive waste storage site, the author shows that numerical modelling is a support to experimental result exploitation, and allows the development of new interpretation and prediction codes. He shows that molecular modelling can be used to study processes of interaction between an actinide ion (notably a uranyl ion) and a mineral surface (a TiO 2 substrate). He also reports the predictive theoretical study of the interaction between an uranyl ion and a gibbsite substrate

  12. BEHAVIORAL INPUTS TO THE THEORETICAL APPROACH OF THE ECONOMIC CRISIS

    Sinziana BALTATESCU

    2015-09-01

    Full Text Available The current economic and financial crisis gave room for the theoretical debates to reemerge. The economic reality challenged the mainstream neoclassical approach leaving the opportunity for the Austrian School, Post Keynesianism or Institutionalists to bring in front theories that seem to better explain the economic crisis and thus, leaving space for more efficient economic policies to result. In this context, the main assumptions of the mainstream theoretical approach are challenged and reevaluated, behavioral economics is one of the main challengers. Without developing in an integrated school of thought yet, behavioral economics brings new elements within the framework of economic thinking. How are the main theoretical approaches integrating these new elements and whether this process is going to narrow the theory or enrich it to be more comprehensive are questions to which this paper tries to answer, or, at least, to leave room for an answer.

  13. Group theory approach to scattering

    Wu, J.

    1985-01-01

    For certain physical systems, there exists a dynamical group which contains the operators connecting states with the same energy but belonging to potentials with different strengths. This group is called the potential group of that system. The SO(2,1) potential groups structure is introduced to describe physical systems with mixed spectra, such as Morse and Poeschl-teller potentials. The discrete spectrum describes bound states and the continuous spectrum describes bound states and the continuous spectrum describes scattering states. A solvable class of one-dimensional potentials given by Natanzon belongs to this structure with an SO(2,2) potential group. The potential group structure provides us with an algebraic procedure generating the recursion relations for the scattering matrix, which can be formulated in a purely algebraic fashion, divorced from any differential realization. This procedure, when applied to the three-dimensional scattering problem with SO(3,1) symmetry, generates the scattering matrix of the Coulomb problem. Preliminary phenomenological models for elastic scattering in a heavy-ion collision are constructed on the basis. The results obtained here can be regarded as an important extension of the group theory techniques to scattering problems similar to that developed for bound state problems

  14. Twistor-theoretic approach to topological field theories

    Ito, Kei.

    1991-12-01

    The two-dimensional topological field theory which describes a four-dimensional self-dual space-time (gravitational instanton) as a target space, which we constructed before, is shown to be deeply connected with Penrose's 'twistor theory'. The relations are presented in detail. Thus our theory offers a 'twistor theoretic' approach to topological field theories. (author)

  15. SOCIOLOGICAL UNDERSTANDING OF INTERNET: THEORETICAL APPROACHES TO THE NETWORK ANALYSIS

    D. E. Dobrinskaya

    2016-01-01

    Full Text Available The network is an efficient way of social structure analysis for contemporary sociologists. It gives broad opportunities for detailed and fruitful research of different patterns of ties and social relations by quantitative analytical methods and visualization of network models. The network metaphor is used as the most representative tool for description of a new type of society. This new type is characterized by flexibility, decentralization and individualization. Network organizational form became the dominant form in modern societies. The network is also used as a mode of inquiry. Actually three theoretical network approaches in the Internet research case are the most relevant: social network analysis, “network society” theory and actor-network theory. Every theoretical approach has got its own notion of network. Their special methodological and theoretical features contribute to the Internet studies in different ways. The article represents a brief overview of these network approaches. This overview demonstrates the absence of a unified semantic space of the notion of “network” category. This fact, in turn, points out the need for detailed analysis of these approaches to reveal their theoretical and empirical possibilities in application to the Internet studies. 

  16. Multiple stakeholders in road pricing: A game theoretic approach

    Ohazulike, Anthony; Still, Georg J.; Kern, Walter; van Berkum, Eric C.; Hausken, Kjell; Zhuang, Jun

    2015-01-01

    We investigate a game theoretic approach as an alternative to the standard multi-objective optimization models for road pricing. Assuming that various, partly conflicting traffic externalities (congestion, air pollution, noise, safety, etcetera) are represented by corresponding players acting on a

  17. An Activity Theoretical Approach to Social Interaction during Study Abroad

    Shively, Rachel L.

    2016-01-01

    This case study examines how one study abroad student oriented to social interaction during a semester in Spain. Using an activity theoretical approach, the findings indicate that the student not only viewed social interaction with his Spanish host family and an expert-Spanish-speaking age peer as an opportunity for second language (L2) learning,…

  18. Evaluation of group theoretical characteristics using the symbolic manipulation language MAPLE

    Taneri, U.; Paldus, J.

    1994-01-01

    Relying on theoretical developments exploiting quasispin and the pseudo-orthogonal group in the Hubbard model of cyclic polyenes, the general expressions for generating polynomials, providing the dimensional information for relevant irreducible representations, were derived. These generating polynomials result from 1-dimensional formulas through rather tedious algebraic manipulations involving ratios of polynomials with fractional powers. It is shown that these expressions may be efficiently handled using the symbolic manipulation language MAPLE and the dimensional information for an arbitrary spin, isospin, and quasimomentum obtained. Exploitation of symbolic computation for other group theoretical problems that are relevant in quantum chemical calculations and their relationship with Guassian polynomial based combinatorial approaches is also briefly addressed and various possible applications outlined

  19. A queer-theoretical approach to community health psychology.

    Easpaig, Bróna R Nic Giolla; Fryer, David M; Linn, Seònaid E; Humphrey, Rhianna H

    2014-01-01

    Queer-theoretical resources offer ways of productively rethinking how central concepts such as 'person-context', 'identity' and 'difference' may be understood for community health psychologists. This would require going beyond consideration of the problems with which queer theory is popularly associated to cautiously engage with the aspects of this work relevant to the promotion of collective practice and engaging with processes of marginalisation. In this article, we will draw upon and illustrate the queer-theoretical concepts of 'performativity' and 'cultural intelligibility' before moving towards a preliminary mapping of what a queer-informed approach to community health psychology might involve.

  20. Monoenergetic approximation of a polyenergetic beam: a theoretical approach

    Robinson, D.M.; Scrimger, J.W.

    1991-01-01

    There exist numerous occasions in which it is desirable to approximate the polyenergetic beams employed in radiation therapy by a beam of photons of a single energy. In some instances, commonly used rules of thumb for the selection of an appropriate energy may be valid. A more accurate approximate energy, however, may be determined by an analysis which takes into account both the spectral qualities of the beam and the material through which it passes. The theoretical basis of this method of analysis is presented in this paper. Experimental agreement with theory for a range of materials and beam qualities is also presented and demonstrates the validity of the theoretical approach taken. (author)

  1. A theoretical approach to artificial intelligence systems in medicine.

    Spyropoulos, B; Papagounos, G

    1995-10-01

    The various theoretical models of disease, the nosology which is accepted by the medical community and the prevalent logic of diagnosis determine both the medical approach as well as the development of the relevant technology including the structure and function of the A.I. systems involved. A.I. systems in medicine, in addition to the specific parameters which enable them to reach a diagnostic and/or therapeutic proposal, entail implicitly theoretical assumptions and socio-cultural attitudes which prejudice the orientation and the final outcome of the procedure. The various models -causal, probabilistic, case-based etc. -are critically examined and their ethical and methodological limitations are brought to light. The lack of a self-consistent theoretical framework in medicine, the multi-faceted character of the human organism as well as the non-explicit nature of the theoretical assumptions involved in A.I. systems restrict them to the role of decision supporting "instruments" rather than regarding them as decision making "devices". This supporting role and, especially, the important function which A.I. systems should have in the structure, the methods and the content of medical education underscore the need of further research in the theoretical aspects and the actual development of such systems.

  2. Model selection and inference a practical information-theoretic approach

    Burnham, Kenneth P

    1998-01-01

    This book is unique in that it covers the philosophy of model-based data analysis and an omnibus strategy for the analysis of empirical data The book introduces information theoretic approaches and focuses critical attention on a priori modeling and the selection of a good approximating model that best represents the inference supported by the data Kullback-Leibler information represents a fundamental quantity in science and is Hirotugu Akaike's basis for model selection The maximized log-likelihood function can be bias-corrected to provide an estimate of expected, relative Kullback-Leibler information This leads to Akaike's Information Criterion (AIC) and various extensions and these are relatively simple and easy to use in practice, but little taught in statistics classes and far less understood in the applied sciences than should be the case The information theoretic approaches provide a unified and rigorous theory, an extension of likelihood theory, an important application of information theory, and are ...

  3. Child education and management: theoretical approaches on legislation

    Rúbia Borges

    2017-11-01

    Full Text Available The aim of this work was to investigate theoretical approaches regarding to daycare centers and management, considering childhood education for different audiences, such children and babies on the childhood perspective. On qualitative approach, this research is bibliographical and reflects on official documents about the theme. The development of this research occurred through analysis on educational Brazilian laws, starting by the Federal Constitution (FC, Law of Guidelines and Bases for National Education (LGB, National Curriculum Guidelines and the Education National Plan (ENP. The results point to a generalist legislation that allow certain autonomy on the education. However, there is the need to deepen theoretical and practical studies on the reality of institutions which have the education as the paramount purpose, in order to offer education with quality and attending to the needs from the audience in these institutions.

  4. Blogging in Higher Education: Theoretical and Practical Approach

    Gulfidan CAN; Devrim OZDEMIR

    2006-01-01

    In this paper the blogging method, which includes new forms of writing, is supported as an alternative approach to address the frequently asserted problems in higher education such as product-oriented assessment and lack of value given to students' writing as contribution to the discourse of the academic disciplines. Both theoretical and research background information is provided to clarify the rationale of using this method in higher education. Furthermore, recommended way of using this met...

  5. Theoretical and expert system approach to photoionization theories

    Petrović Ivan D.

    2016-01-01

    Full Text Available The influence of the ponderomotive and the Stark shifts on the tunneling transition rate was observed, for non-relativistic linearly polarized laser field for alkali atoms, with three different theoretical models, the Keldysh theory, the Perelomov, Popov, Terent'ev (PPT theory, and the Ammosov, Delone, Krainov (ADK theory. We showed that aforementioned shifts affect the transition rate differently for different approaches. Finally, we presented a simple expert system for analysis of photoionization theories.

  6. Group theoretical construction of planar noncommutative phase spaces

    Ngendakumana, Ancille, E-mail: nancille@yahoo.fr; Todjihoundé, Leonard, E-mail: leonardt@imsp.uac.org [Institut de Mathématiques et des Sciences Physiques (IMSP), Porto-Novo (Benin); Nzotungicimpaye, Joachim, E-mail: kimpaye@kie.ac.rw [Kigali Institute of Education (KIE), Kigali (Rwanda)

    2014-01-15

    Noncommutative phase spaces are generated and classified in the framework of centrally extended anisotropic planar kinematical Lie groups as well as in the framework of noncentrally abelian extended planar absolute time Lie groups. Through these constructions the coordinates of the phase spaces do not commute due to the presence of naturally introduced fields giving rise to minimal couplings. By symplectic realizations methods, physical interpretations of generators coming from the obtained structures are given.

  7. Group theoretical construction of planar noncommutative phase spaces

    Ngendakumana, Ancille; Todjihoundé, Leonard; Nzotungicimpaye, Joachim

    2014-01-01

    Noncommutative phase spaces are generated and classified in the framework of centrally extended anisotropic planar kinematical Lie groups as well as in the framework of noncentrally abelian extended planar absolute time Lie groups. Through these constructions the coordinates of the phase spaces do not commute due to the presence of naturally introduced fields giving rise to minimal couplings. By symplectic realizations methods, physical interpretations of generators coming from the obtained structures are given

  8. Principle-theoretic approach of kondo and construction-theoretic formalism of gauge theories

    Jain, L.C.

    1986-01-01

    Einstein classified various theories in physics as principle-theories and constructive-theories. In this lecture Kondo's approach to microscopic and macroscopic phenomena is analysed for its principle theoretic pursuit as followed by construction. The fundamentals of his theory may be recalled as Tristimulus principle, Observation principle, Kawaguchi spaces, empirical information, epistemological point of view, unitarity, intrinsicality, and dimensional analysis subject to logical and geometrical achievement. On the other hand, various physicists have evolved constructive gauge theories through the phenomenological point of view, often a collective one. Their synthetic method involves fibre bundles and connections, path integrals as well as other hypothetical structures. They lead towards clarity, completeness and adaptability

  9. Theoretical orientations in environmental planning: An inquiry into alternative approaches

    Briassoulis, Helen

    1989-07-01

    In the process of devising courses of action to resolve problems arising at the society-environment interface, a variety of planning approaches are followed, whose adoption is influenced by—among other things—the characteristics of environmental problems, the nature of the decision-making context, and the intellectual traditions of the disciplines contributing to the study of these problems. This article provides a systematic analysis of six alternative environmental planning approaches—comprehensive/rational, incremental, adaptive, contingency, advocacy, and participatory/consensual. The relative influence of the abovementioned factors is examined, the occurrence of these approaches in real-world situations is noted, and their environmental soundness and political realism is evaluated. Because of the disparity between plan formulation and implementation and between theoretical form and empirical reality, a synthetic view of environmental planning approaches is taken and approaches in action are identified, which characterize the totality of the planning process from problem definition to plan implementation, as well as approaches in the becoming, which may be on the horizon of environmental planning of tomorrow. The suggested future research directions include case studies to verify and detail the presence of the approaches discussed, developing measures of success of a given approach in a given decision setting, and an intertemporal analysis of environmental planning approaches.

  10. Theoretical aspects of graphene-like group IV semiconductors

    Houssa, M.; Broek, B. van den; Scalise, E.; Ealet, B.; Pourtois, G.; Chiappe, D.; Cinquanta, E.; Grazianetti, C.; Fanciulli, M.; Molle, A.; Afanas’ev, V.V.; Stesmans, A.

    2014-01-01

    Silicene and germanene are the silicon and germanium counterparts of graphene, respectively. Recent experimental works have reported the growth of silicene on (1 1 1)Ag surfaces with different atomic configurations, depending on the growth temperature and surface coverage. We first theoretically study the structural and electronic properties of silicene on (1 1 1)Ag surfaces, focusing on the (4 × 4)silicene/Ag structure. Due to symmetry breaking in the silicene layer (nonequivalent number of top and bottom Si atoms), the corrugated silicene layer, with the Ag substrate removed, is predicted to be semiconducting, with a computed energy bandgap of about 0.3 eV. However, the hybridization between the Si 3p orbitals and the Ag 5s orbital in the silicene/(1 1 1)Ag slab model leads to an overall metallic system, with a distribution of local electronic density of states, which is related to the slightly disordered structure of the silicene layer on the (1 1 1)Ag surface. We next study the interaction of silicene and germanene with different hexagonal non-metallic substrates, namely ZnS and ZnSe. On reconstructed (0 0 0 1)ZnS or ZnSe surfaces, which should be more energetically stable for very thin layers, silicene and germanene are found to be semiconducting. Remarkably, the nature and magnitude of their energy bandgap can be controlled by an out-of-plane electric field, an important finding for the potential use of these materials in nanoelectronic devices.

  11. Theoretical aspects of graphene-like group IV semiconductors

    Houssa, M., E-mail: michel.houssa@fys.kuleuven.be [Department of Physics and Astronomy, University of Leuven, B-3001 Leuven (Belgium); Broek, B. van den; Scalise, E. [Department of Physics and Astronomy, University of Leuven, B-3001 Leuven (Belgium); Ealet, B. [Aix-Marseille University, CNRS-CINaM Laboratory, 13288 Marseille (France); Pourtois, G. [imec, Kapeldreef 75, B-3001 Leuven (Belgium); Plasmant Research Group, University of Antwerp, B-2610 Wilrijk-Antwerp (Belgium); Chiappe, D.; Cinquanta, E. [MDM Laboratory, IMM-CNR, I-20864 Agrate Brianza (Italy); Grazianetti, C.; Fanciulli, M. [MDM Laboratory, IMM-CNR, I-20864 Agrate Brianza (Italy); Universita degli Studi di Milano Bicocca, 20126 Milano (Italy); Molle, A. [MDM Laboratory, IMM-CNR, I-20864 Agrate Brianza (Italy); Afanas’ev, V.V.; Stesmans, A. [Department of Physics and Astronomy, University of Leuven, B-3001 Leuven (Belgium)

    2014-02-01

    Silicene and germanene are the silicon and germanium counterparts of graphene, respectively. Recent experimental works have reported the growth of silicene on (1 1 1)Ag surfaces with different atomic configurations, depending on the growth temperature and surface coverage. We first theoretically study the structural and electronic properties of silicene on (1 1 1)Ag surfaces, focusing on the (4 × 4)silicene/Ag structure. Due to symmetry breaking in the silicene layer (nonequivalent number of top and bottom Si atoms), the corrugated silicene layer, with the Ag substrate removed, is predicted to be semiconducting, with a computed energy bandgap of about 0.3 eV. However, the hybridization between the Si 3p orbitals and the Ag 5s orbital in the silicene/(1 1 1)Ag slab model leads to an overall metallic system, with a distribution of local electronic density of states, which is related to the slightly disordered structure of the silicene layer on the (1 1 1)Ag surface. We next study the interaction of silicene and germanene with different hexagonal non-metallic substrates, namely ZnS and ZnSe. On reconstructed (0 0 0 1)ZnS or ZnSe surfaces, which should be more energetically stable for very thin layers, silicene and germanene are found to be semiconducting. Remarkably, the nature and magnitude of their energy bandgap can be controlled by an out-of-plane electric field, an important finding for the potential use of these materials in nanoelectronic devices.

  12. A Decision-Theoretic Basis for Choice Shifts in Groups

    Eliaz, Kfir; Ray, Debraj; Razin, Ronny

    2004-01-01

    The phenomenon of choice shifts in group decision-making is fairly ubiquitous in the social psychology literature. Faced with a choice between a ‘safe’ and ‘risky’ decision, group members appear to move to one extreme or the other, relative to the choices each member might have made alone. Both risky and cautious shifts have been identified in different situations. This Paper demonstrates that from an individual decision-making perspective, choice shifts may be viewed as a systematic violatio...

  13. THEORETICAL PRINCIPLES OF PSYCHOLOGICAL ANALYSIS OF STUDENTS’ GROUP PROJECT ACTIVITY WHILE LEARNING FOREIGN LANGUAGE

    Viktoriia Kalamazh

    2016-06-01

    Full Text Available In this research the theoretical principles of psychological analysis of group project activity of students in the process of learning foreign language are defined on the basis of subject-activity, socio-psychological and cognitive paradigms. The approaches of different authors to the understanding of the concept of project and in particular group project activity are considered. The difficulties of the theoretical analysis of this specific notion are indicated due to the considerable variety of subjects, types and forms of the pedagogical activity, academic disciplines regarding which the researches are being carried out. Not disclosed aspects of organizing the group project activity of students are being determined, among them is a project group as an autonomous subject of joint activity for the realization students’ project activity while learning a foreign language; forming psychological readiness of teacher and student to use project method; the role of metacognitive aspect in the surrounding, where the project activity is being carried out; group functioning through the project work as a subject of group examination. It has been indicated that the analysis of project activity as an innovative technology must include its assessment as a condition of student’s developing as a subject of learning activity, his personal, socio-psychological, intellectual and professional self-perfection. Three levels of subjectivity in group project activity are being distinguished: teacher; each particular student; and student project group. Interaction between teacher and student is based on subject-subject relations. An organization of a project activity while learning a foreign language is considered as the one in which the student is moving in order to get the manager position and to master the basis of expert knowledge. Hereby, the main stress is on the group role as a subject of group examination, and also on metacognitive character of the

  14. A System Theoretical Inspired Approach to Knowledge Construction

    Mathiasen, Helle

    2008-01-01

    student's knowledge construction, in the light of operative constructivism, inspired by the German sociologist N. Luhmann's system theoretical approach to epistemology. Taking observations as operations based on distinction and indication (selection) contingency becomes a fundamental condition in learning......  Abstract The aim of this paper is to discuss the relation between teaching and learning. The point of departure is that teaching environments (communication forums) is a potential facilitator for learning processes and knowledge construction. The paper present a theoretical frame work, to discuss...... processes, and a condition which teaching must address as far as teaching strives to stimulate non-random learning outcomes. Thus learning outcomes understood as the individual learner's knowledge construction cannot be directly predicted from events and characteristics in the environment. This has...

  15. Information Ergonomics A theoretical approach and practical experience in transportation

    Sandl, Peter

    2012-01-01

    The variety and increasing availability of hypermedia information systems, which are used in stationary applications like operators’ consoles as well as mobile systems, e.g. driver information and navigation systems in automobiles form a foundation for the mediatization of the society. From the human engineering point of view this development and the ensuing increased importance of information systems for economic and private needs require careful deliberation of the derivation and application of ergonomics methods particularly in the field of information systems. This book consists of two closely intertwined parts. The first, theoretical part defines the concept of an information system, followed by an explanation of action regulation as well as cognitive theories to describe man information system interaction. A comprehensive description of information ergonomics concludes the theoretical approach. In the second, practically oriented part of this book authors from industry as well as from academic institu...

  16. Application of the group-theoretical method to physical problems

    Abd-el-malek, Mina B.

    1998-01-01

    The concept of the theory of continuous groups of transformations has attracted the attention of applied mathematicians and engineers to solve many physical problems in the engineering sciences. Three applications are presented in this paper. The first one is the problem of time-dependent vertical temperature distribution in a stagnant lake. Two cases have been considered for the forms of the water parameters, namely water density and thermal conductivity. The second application is the unstea...

  17. The Bogolyubov renormalization group in theoretical and mathematical physics

    Shirkov, D.V.

    1999-01-01

    This text follows the line of a talk on Ringberg symposium dedicated to Wolfhart Zimmermann 70th birthday. The historical overview (Part I) partially overlaps with corresponding text of my previous commemorative paper - see Ref. [6] in the list. At the same time the second part includes some fresh results in QFT (Sect. 2.1.) and summarizes (Sect. 2.4) an impressive recent progress of the 'QFT renormalization group' application in mathematical physics

  18. Description of group-theoretical model of developed turbulence

    Saveliev, V L; Gorokhovski, M A

    2008-01-01

    We propose to associate the phenomenon of stationary turbulence with the special self-similar solutions of the Euler equations. These solutions represent the linear superposition of eigenfields of spatial symmetry subgroup generators and imply their dependence on time through the parameter of the symmetry transformation only. From this model, it follows that for developed turbulent process, changing the scale of averaging (filtering) of the velocity field is equivalent to composition of scaling, translation and rotation transformations. We call this property a renormalization-group invariance of filtered turbulent fields. The renormalization group invariance provides an opportunity to transform the averaged Navier-Stokes equation over a small scale (inner threshold of the turbulence) to larger scales by simple scaling. From the methodological point of view, it is significant to note that the turbulent viscosity term appeared not as a result of averaging of the nonlinear term in the Navier-Stokes equation, but from the molecular viscosity term with the help of renormalization group transformation.

  19. PREFACE: XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP) (Group30)

    Brackx, Fred; De Schepper, Hennie; Van der Jeugt, Joris

    2015-04-01

    The XXXth International Colloquium on Group Theoretical Methods in Physics (ICGTMP), also known as the Group30 conference, took place in Ghent (Belgium) from Monday 14 to Friday 18 July 2014. The conference was organised by Ghent University (Department of Applied Mathematics, Computer Science and Statistics, and Department of Mathematical Analysis). The website http://www.group30.ugent.be is still available. The ICGTMP is one of the traditional conference series covering the most important topics of symmetry which are relevant to the interplay of present-day mathematics and physics. More than 40 years ago a group of enthusiasts, headed by H. Bacry of Marseille and A. Janner of Nijmegen, initiated a series of annual meetings with the aim to provide a common forum for scientists interested in group theoretical methods. At that time most of the participants belonged to two important communities: on the one hand solid state specialists, elementary particle theorists and phenomenologists, and on the other mathematicians eager to apply newly-discovered group and algebraic structures. The conference series has become a meeting point for scientists working at modelling physical phenomena through mathematical and numerical methods based on geometry and symmetry. It is considered as the oldest one among the conference series devoted to geometry and physics. It has been further broadened and diversified due to the successful applications of geometric and algebraic methods in life sciences and other areas. The first four meetings took place alternatively in Marseille and Nijmegen. Soon after, the conference acquired an international standing, especially following the 1975 colloquium in Nijmegen and the 1976 colloquium in Montreal. Since then it has been organized in many places around the world. It has become a bi-annual colloquium since 1990, the year it was organized in Moscow. This was the first time the colloquium took place in Belgium. There were 246 registered

  20. SOCIOLOGICAL UNDERSTANDING OF INTERNET: THEORETICAL APPROACHES TO THE NETWORK ANALYSIS

    D. E. Dobrinskaya

    2016-01-01

    Full Text Available Internet studies are carried out by various scientific disciplines and in different research perspectives. Sociological studies of the Internet deal with a new technology, a revolutionary means of mass communication and a social space. There is a set of research difficulties associated with the Internet. Firstly, the high speed and wide spread of Internet technologies’ development. Secondly, the collection and filtration of materials concerning with Internet studies. Lastly, the development of new conceptual categories, which are able to reflect the impact of the Internet development in contemporary world. In that regard the question of the “network” category use is essential. Network is the base of Internet functioning, on the one hand. On the other hand, network is the ground for almost all social interactions in modern society. So such society is called network society. Three theoretical network approaches in the Internet research case are the most relevant: network society theory, social network analysis and actor-network theory. Each of these theoretical approaches contributes to the study of the Internet. They shape various images of interactions between human beings in their entity and dynamics. All these approaches also provide information about the nature of these interactions. 

  1. Theoretical approaches to determining the financial provision of public transportation

    O.A. Vygovska

    2018-03-01

    Full Text Available The work is devoted to the improvement of theoretical approaches in determining the financial provision of transportation by public transport at the regional level. The author summarizes the concept of the «financial security» and defines the main difference from the term «financing». The systematization of key differences in the financial provision of a transport company from other financial entities of the economic sector at the national and regional levels is carried out. The disadvantages and advantages of sources of financial support are analyzed. The purpose of the article is to study theoretical approaches in determining the financial provision of transportation by public transport at the regional level. The prospects for further scientific research are the need to identify new scientific approaches and techniques to substantiate and elaborate the concept of the «financial provision of transportation by public transport». The practical application of the research should be formed in a detailed analysis of cash flow streams in the system of «state – regional authority – economic entity». The financial provision of transportation by public transport at the regional level has not been given the sufficient attention in the scientific research within the country. This fact confirms the need for a thorough analysis of the transport industry as a whole.

  2. Success Determination by Innovation: A Theoretical Approach in Marketing

    Raj Kumar Gautam

    2012-10-01

    Full Text Available The paper aims at to identify the main issues in the marketing which needs immediate attention of the marketers. The importance of innovation in the marketing has also been highlighted and marketing mix have been related to innovative and creative ideas. The study is based on the secondary data, various research papers, articles has been studied to develop a innovative approach in the marketing. Marketing innovative ideas relating to business lead generation, product, price, distribution, promotion of product, and revenue generation have been highlighted in the paper. All the suggestions are theoretical and may have relevance and implication to the marketers.

  3. Success Determination by Innovation: A Theoretical Approach in Marketing

    Raj Kumar Gautam

    2012-11-01

    Full Text Available The paper aims at to identify the main issues in the marketing which needs immediate attention of the marketers. The importance of innovation in the marketing has also been highlighted and marketing mix have been related to innovative and creative ideas. The study is based on the secondary data, various research papers, articles has been studied to develop a innovative approach in the marketing. Marketing innovative ideas relating to business lead generation, product, price, distribution, promotion of product, and revenue generation have been highlighted in the paper. All the suggestions are theoretical and may have relevance and implication to the marketers.

  4. Vanadium supersaturated silicon system: a theoretical and experimental approach

    Garcia-Hemme, Eric; García, Gregorio; Palacios, Pablo; Montero, Daniel; García-Hernansanz, Rodrigo; Gonzalez-Diaz, Germán; Wahnon, Perla

    2017-12-01

    The effect of high dose vanadium ion implantation and pulsed laser annealing on the crystal structure and sub-bandgap optical absorption features of V-supersaturated silicon samples has been studied through the combination of experimental and theoretical approaches. Interest in V-supersaturated Si focusses on its potential as a material having a new band within the Si bandgap. Rutherford backscattering spectrometry measurements and formation energies computed through quantum calculations provide evidence that V atoms are mainly located at interstitial positions. The response of sub-bandgap spectral photoconductance is extended far into the infrared region of the spectrum. Theoretical simulations (based on density functional theory and many-body perturbation in GW approximation) bring to light that, in addition to V atoms at interstitial positions, Si defects should also be taken into account in explaining the experimental profile of the spectral photoconductance. The combination of experimental and theoretical methods provides evidence that the improved spectral photoconductance up to 6.2 µm (0.2 eV) is due to new sub-bandgap transitions, for which the new band due to V atoms within the Si bandgap plays an essential role. This enables the use of V-supersaturated silicon in the third generation of photovoltaic devices.

  5. Theoretical, Methodological, and Empirical Approaches to Cost Savings: A Compendium

    M Weimar

    1998-12-10

    This publication summarizes and contains the original documentation for understanding why the U.S. Department of Energy's (DOE's) privatization approach provides cost savings and the different approaches that could be used in calculating cost savings for the Tank Waste Remediation System (TWRS) Phase I contract. The initial section summarizes the approaches in the different papers. The appendices are the individual source papers which have been reviewed by individuals outside of the Pacific Northwest National Laboratory and the TWRS Program. Appendix A provides a theoretical basis for and estimate of the level of savings that can be" obtained from a fixed-priced contract with performance risk maintained by the contractor. Appendix B provides the methodology for determining cost savings when comparing a fixed-priced contractor with a Management and Operations (M&O) contractor (cost-plus contractor). Appendix C summarizes the economic model used to calculate cost savings and provides hypothetical output from preliminary calculations. Appendix D provides the summary of the approach for the DOE-Richland Operations Office (RL) estimate of the M&O contractor to perform the same work as BNFL Inc. Appendix E contains information on cost growth and per metric ton of glass costs for high-level waste at two other DOE sites, West Valley and Savannah River. Appendix F addresses a risk allocation analysis of the BNFL proposal that indicates,that the current approach is still better than the alternative.

  6. Towards a Set Theoretical Approach to Big Data Analytics

    Mukkamala, Raghava Rao; Hussain, Abid; Vatrapu, Ravi

    2014-01-01

    Formal methods, models and tools for social big data analytics are largely limited to graph theoretical approaches such as social network analysis (SNA) informed by relational sociology. There are no other unified modeling approaches to social big data that integrate the conceptual, formal...... this technique to the data analysis of big social data collected from Facebook page of the fast fashion company, H&M....... and software realms. In this paper, we first present and discuss a theory and conceptual model of social data. Second, we outline a formal model based on set theory and discuss the semantics of the formal model with a real-world social data example from Facebook. Third, we briefly present and discuss...

  7. Introduction to superfluidity field-theoretical approach and applications

    Schmitt, Andreas

    2015-01-01

    Superfluidity – and closely related to it, superconductivity – are very general phenomena that can occur on vastly different energy scales. Their underlying theoretical mechanism of spontaneous symmetry breaking is even more general and applies to a multitude of physical systems.  In these lecture notes, a pedagogical introduction to the field-theory approach to superfluidity is presented. The connection to more traditional approaches, often formulated in a different language, is carefully explained in order to provide a consistent picture that is useful for students and researchers in all fields of physics. After introducing the basic concepts, such as the two-fluid model and the Goldstone mode, selected topics of current research are addressed, such as the BCS-BEC crossover and Cooper pairing with mismatched Fermi momenta.

  8. How cells engulf: a review of theoretical approaches to phagocytosis

    Richards, David M.; Endres, Robert G.

    2017-12-01

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

  9. Nuclear Fermi Dynamics: physical content versus theoretical approach

    Griffin, J.J.

    1977-01-01

    Those qualitative properties of nuclei, and of their energetic collisions, which seem of most importance for the flow of nuclear matter are listed and briefly discussed. It is suggested that nuclear matter flow is novel among fluid dynamical problems. The name, Nuclear Fermi Dynamics, is proposed as an appropriate unambiguous label. The Principle of Commensurability, which suggests the measurement of the theoretical content of an approach against its expected predictive range is set forth and discussed. Several of the current approaches to the nuclear matter flow problem are listed and subjected to such a test. It is found that the Time-Dependent Hartree-Fock (TDHF) description, alone of all the major theoretical approaches currently in vogue, incorporates each of the major qualitative features within its very concise single mathematical assumption. Some limitations of the conventional TDHF method are noted, and one particular defect is discussed in detail: the Spurious Cross Channel Correlations which arise whenever several asymptotic reaction channels must be simultaneously described by a single determinant. A reformulated Time-Dependent-S-Matrix Hartree-Fock Theory is proposed, which obviates this difficulty. It is noted that the structure of TD-S-HF can be applied to a more general class of non-linear wave mechanical problems than simple TDHF. Physical requirements minimal to assure that TD-S-HF represents a sensible reaction theory are utilized to prescribe the definition of acceptable asymptotic channels. That definition, in turn, defines the physical range of the TD-S-HF theory as the description of collisions of certain mathematically well-defined objects of mixed quantal and classical character, the ''TDHF droplets.''

  10. Nursing leadership in a chronic pain management group approach.

    Dysvik, Elin; Furnes, Bodil

    2012-03-01

    To explore and debate nursing leadership and challenges on organizational and group levels when conducting rehabilitation groups for people suffering from chronic pain. Group approaches based on cognitive behavioural therapy are generally described as effective. Leadership in group approaches offered to people suffering from chronic pain is a great challenge for nurses on an organizational as well as a group level. One overall leader and nine group leaders conducting 13 groups constituted the sample. Qualitative content analysis was used by identifying categories, subthemes and themes. The results from the content analysis revealed one main theme ('Complexity in nursing leadership') and three subthemes ('Challenges in leadership on organizational level', 'Challenges in leadership on teamwork level' and 'Challenges in leadership on group level'. The results show how important it is to have firm overall leadership and trained group leaders with a common purpose, interdependent roles and complementary skills, who are thus well prepared to prevent or deal with challenging group processes. The leaders of both levels, which are highly interrelated, should have a current theoretical understanding of pain theory, group leadership skills and a cognitive behavioural approach. © 2012 Blackwell Publishing Ltd.

  11. Analytic game—theoretic approach to ground-water extraction

    Loáiciga, Hugo A.

    2004-09-01

    The roles of cooperation and non-cooperation in the sustainable exploitation of a jointly used groundwater resource have been quantified mathematically using an analytical game-theoretic formulation. Cooperative equilibrium arises when ground-water users respect water-level constraints and consider mutual impacts, which allows them to derive economic benefits from ground-water indefinitely, that is, to achieve sustainability. This work shows that cooperative equilibrium can be obtained from the solution of a quadratic programming problem. For cooperative equilibrium to hold, however, enforcement must be effective. Otherwise, according to the commonized costs-privatized profits paradox, there is a natural tendency towards non-cooperation and non-sustainable aquifer mining, of which overdraft is a typical symptom. Non-cooperative behavior arises when at least one ground-water user neglects the externalities of his adopted ground-water pumping strategy. In this instance, water-level constraints may be violated in a relatively short time and the economic benefits from ground-water extraction fall below those obtained with cooperative aquifer use. One example illustrates the game theoretic approach of this work.

  12. Factors determining early internationalization of entrepreneurial SMEs: Theoretical approach

    Agne Matiusinaite

    2015-12-01

    Full Text Available Purpose – This study extends the scientific discussion of early internationalization of SMEs. The main purpose of this paper – to develop a theoretical framework to investigate factors determining early internationalization of international new ventures. Design/methodology/approach – The conceptual framework is built on the analysis and synthesis of scientific literature. Findings – This paper presents different factors, which determine early internationalization of international new ventures. These factors are divided to entrepreneurial, organizational and contextual factors. We argue that early internationalization of international new ventures is defined by entrepreneurial characteristics and previous experience of the entrepreneur, opportunities recognition and exploitation, risk tolerance, specific of the organization, involvement into networks and contextual factors. Study proved that only interaction between factors and categories has an effect for business development and successful implementation of early internationalization. Research limitations/implications – The research was conducted on the theoretical basis of scientific literature. The future studies could include a practical confirmation or denial of such allocation of factors. Originality/value – The originality of this study lies in the finding that factor itself has limited effect to early internationalization. Only the interoperability of categories and factors gives a positive impact on early internationalization of entrepreneurial SMEs.

  13. Investigations on Actuator Dynamics through Theoretical and Finite Element Approach

    Somashekhar S. Hiremath

    2010-01-01

    Full Text Available This paper gives a new approach for modeling the fluid-structure interaction of servovalve component-actuator. The analyzed valve is a precision flow control valve-jet pipe electrohydraulic servovalve. The positioning of an actuator depends upon the flow rate from control ports, in turn depends on the spool position. Theoretical investigation is made for No-load condition and Load condition for an actuator. These are used in finite element modeling of an actuator. The fluid-structure-interaction (FSI is established between the piston and the fluid cavities at the piston end. The fluid cavities were modeled with special purpose hydrostatic fluid elements while the piston is modeled with brick elements. The finite element method is used to simulate the variation of cavity pressure, cavity volume, mass flow rate, and the actuator velocity. The finite element analysis is extended to study the system's linearized response to harmonic excitation using direct solution steady-state dynamics. It was observed from the analysis that the natural frequency of the actuator depends upon the position of the piston in the cylinder. This is a close match with theoretical and simulation results. The effect of bulk modulus is also presented in the paper.

  14. Towards a capability approach to child growth: A theoretical framework.

    Haisma, Hinke; Yousefzadeh, Sepideh; Boele Van Hensbroek, Pieter

    2018-04-01

    Child malnutrition is an important cause of under-5 mortality and morbidity around the globe. Despite the partial success of (inter)national efforts to reduce child mortality, under-5 mortality rates continue to be high. The multidimensional approaches of the Sustainable Development Goals may suggest new directions for rethinking strategies for reducing child mortality and malnutrition. We propose a theoretical framework for developing a "capability" approach to child growth. The current child growth monitoring practices are based on 2 assumptions: (a) that anthropometric and motor development measures are the appropriate indicators; and (b) that child growth can be assessed using a single universal standard that is applicable around the world. These practices may be further advanced by applying a capability approach to child growth, whereby growth is redefined as the achievement of certain capabilities (of society, parents, and children). This framework is similar to the multidimensional approach to societal development presented in the seminal work of Amartya Sen. To identify the dimensions of healthy child growth, we draw upon theories from the social sciences and evolutionary biology. Conceptually, we consider growth as a plural space and propose assessing growth by means of a child growth matrix in which the context is embedded in the assessment. This approach will better address the diversities and the inequalities in child growth. Such a multidimensional measure will have implications for interventions and policy, including prevention and counselling, and could have an impact on child malnutrition and mortality. © 2017 The Authors. Maternal and Child Nutrition Published by John Wiley & Sons, Ltd.

  15. A theoretical approach to photosynthetically active radiation silicon sensor

    Tamasi, M.J.L.; Martínez Bogado, M.G.

    2013-01-01

    This paper presents a theoretical approach for the development of low cost radiometers to measure photosynthetically active radiation (PAR). Two alternatives are considered: a) glass optical filters attached to a silicon sensor, and b) dielectric coating on a silicon sensor. The devices proposed are based on radiometers previously developed by the Argentine National Atomic Energy Commission. The objective of this work is to adapt these low cost radiometers to construct reliable instruments for measuring PAR. The transmittance of optical filters and sensor response have been analyzed for different dielectric materials, number of layers deposited, and incidence angles. Uncertainties in thickness of layer deposition were evaluated. - Highlights: • Design of radiometers to measure photosynthetically active radiation • The study has used a filter and a Si sensor to modify spectral response. • Dielectric multilayers on glass and silicon sensor • Spectral response related to different incidence angles, materials and spectra

  16. Theories of behaviour change synthesised into a set of theoretical groupings: introducing a thematic series on the theoretical domains framework.

    Francis, Jill J; O'Connor, Denise; Curran, Janet

    2012-04-24

    Behaviour change is key to increasing the uptake of evidence into healthcare practice. Designing behaviour-change interventions first requires problem analysis, ideally informed by theory. Yet the large number of partly overlapping theories of behaviour makes it difficult to select the most appropriate theory. The need for an overarching theoretical framework of behaviour change was addressed in research in which 128 explanatory constructs from 33 theories of behaviour were identified and grouped. The resulting Theoretical Domains Framework (TDF) appears to be a helpful basis for investigating implementation problems. Research groups in several countries have conducted TDF-based studies. It seems timely to bring together the experience of these teams in a thematic series to demonstrate further applications and to report key developments. This overview article describes the TDF, provides a brief critique of the framework, and introduces this thematic series.In a brief review to assess the extent of TDF-based research, we identified 133 papers that cite the framework. Of these, 17 used the TDF as the basis for empirical studies to explore health professionals' behaviour. The identified papers provide evidence of the impact of the TDF on implementation research. Two major strengths of the framework are its theoretical coverage and its capacity to elicit beliefs that could signify key mediators of behaviour change. The TDF provides a useful conceptual basis for assessing implementation problems, designing interventions to enhance healthcare practice, and understanding behaviour-change processes. We discuss limitations and research challenges and introduce papers in this series.

  17. Group Theoretical Approach for Controlled Quantum Mechanical Systems

    Tarn, Tzyh-Jong

    2007-01-01

    The aim of this research is the study of controllability of quantum mechanical systems and feedback control of de-coherence in order to gain an insight on the structure of control of quantum systems...

  18. Online adaptive approach for a game-theoretic strategy for complete vehicle energy management

    Chen, H.; Kessels, J.T.B.A.; Weiland, S.

    2015-01-01

    This paper introduces an adaptive approach for a game-theoretic strategy on Complete Vehicle Energy Management. The proposed method enhances the game-theoretic approach such that the strategy is able to adapt to real driving behavior. The classical game-theoretic approach relies on one probability

  19. An integrated theoretical and practical approach for teaching hydrogeology

    Bonomi, Tullia; Fumagalli, Letizia; Cavallin, Angelo

    2013-04-01

    Hydrogeology as an earth science intersects the broader disciplines of geology, engineering, and environmental studies but it does not overlap fully with any of them. It is focused on its own range of problems and over time has developed a rich variety of methods and approaches. The resolution of many hydrogeological problems requires knowledge of elements of geology, hydraulics, physics and chemistry; moreover in recent years the knowledge of modelling techniques has become a necessary ability. Successful transfer of all this knowledge to the students depends on the breadth of material taught in courses, the natural skills of the students and any practical experience the students can obtain. In the Department of Earth and Environmental Sciences of the University of Milano-Bicocca, the teaching of hydrogeology is developed in three inter-related courses: 1) general hydrogeology, 2) applied hydrogeology, 3) groundwater pollution and remediation. The sequence focuses on both groundwater flux and contaminant transport, supplemented by workshops involving case studies and computer labs, which provide the students with practical translation of the theoretical aspects of the science into the world of work. A second key aspect of the program utilizes the students' skill at learning through online approaches, and this is done through three approaches: A) by developing the courses on a University e-learning platform that allows the students to download lectures, articles, and teacher comments, and to participate in online forums; B) by carring out exercises through computer labs where the student analyze and process hydrogeological data by means of different numerical codes, that in turn enable them to manage databases and to perform aquifer test analysis, geostatistical analysis, and flux and transport modelling both in the unsaturated and saturated zone. These exercises are of course preceded by theoretical lectures on codes and software, highlighting their features and

  20. Optimization of Investment Planning Based on Game-Theoretic Approach

    Elena Vladimirovna Butsenko

    2018-03-01

    Full Text Available The game-theoretic approach has a vast potential in solving economic problems. On the other hand, the theory of games itself can be enriched by the studies of real problems of decision-making. Hence, this study is aimed at developing and testing the game-theoretic technique to optimize the management of investment planning. This technique enables to forecast the results and manage the processes of investment planning. The proposed method of optimizing the management of investment planning allows to choose the best development strategy of an enterprise. This technique uses the “game with nature” model, and the Wald criterion, the maximum criterion and the Hurwitz criterion as criteria. The article presents a new algorithm for constructing the proposed econometric method to optimize investment project management. This algorithm combines the methods of matrix games. Furthermore, I show the implementation of this technique in a block diagram. The algorithm includes the formation of initial data, the elements of the payment matrix, as well as the definition of maximin, maximal, compromise and optimal management strategies. The methodology is tested on the example of the passenger transportation enterprise of the Sverdlovsk Railway in Ekaterinburg. The application of the proposed methodology and the corresponding algorithm allowed to obtain an optimal price strategy for transporting passengers for one direction of traffic. This price strategy contributes to an increase in the company’s income with minimal risk from the launch of this direction. The obtained results and conclusions show the effectiveness of using the developed methodology for optimizing the management of investment processes in the enterprise. The results of the research can be used as a basis for the development of an appropriate tool and applied by any economic entity in its investment activities.

  1. A Theoretical Explanation of Marital Conflicts by Paradigmatic Approach

    اسماعیل جهانی دولت آباد

    2017-06-01

    Full Text Available Due to the economic, social and cultural changes in recent decades and consequently alterations in the form and duties of families and expectations of individuals from marriage, the institution of the family and marriage are enormously involved with different challenges and conflicts in comparison to past years. Fragile marital relationships, conflicts and divorce are results of such situations in Iran. Accordingly, the present study, which is designed through meta-analysis and deduction based on the concept analysis and reconceptualization of recent studies, has committed to manifest a proper different paradigm to explain marital conflicts. This paradigm is relying on various theoretical approaches, particularly the theory of symbolic interactionism as the main explanatory mean, and also applying the concept of “Marital Paradigm” as the missing information in previous studies of this field. It explains the marital conflicts between couples as paradigmatic conflicts; and its main idea is that marital conflict is not the result of one or more fixed and specified factors, but it is the production of encountering the opposing (or different paradigms.

  2. Intelligent cognitive radio jamming - a game-theoretical approach

    Dabcevic, Kresimir; Betancourt, Alejandro; Marcenaro, Lucio; Regazzoni, Carlo S.

    2014-12-01

    Cognitive radio (CR) promises to be a solution for the spectrum underutilization problems. However, security issues pertaining to cognitive radio technology are still an understudied topic. One of the prevailing such issues are intelligent radio frequency (RF) jamming attacks, where adversaries are able to exploit on-the-fly reconfigurability potentials and learning mechanisms of cognitive radios in order to devise and deploy advanced jamming tactics. In this paper, we use a game-theoretical approach to analyze jamming/anti-jamming behavior between cognitive radio systems. A non-zero-sum game with incomplete information on an opponent's strategy and payoff is modelled as an extension of Markov decision process (MDP). Learning algorithms based on adaptive payoff play and fictitious play are considered. A combination of frequency hopping and power alteration is deployed as an anti-jamming scheme. A real-life software-defined radio (SDR) platform is used in order to perform measurements useful for quantifying the jamming impacts, as well as to infer relevant hardware-related properties. Results of these measurements are then used as parameters for the modelled jamming/anti-jamming game and are compared to the Nash equilibrium of the game. Simulation results indicate, among other, the benefit provided to the jammer when it is employed with the spectrum sensing algorithm in proactive frequency hopping and power alteration schemes.

  3. The Economic Security of Bank: Theoretical Basis and Systemic Approach

    Gavlovska Nataliia I.

    2017-07-01

    Full Text Available The article analyzes the existing approaches to interpreting the category of «economic security of bank». A author’s own definition of the concept of «economic security of bank» has been proposed, which should be understood as condition of protecting the vital interests of bank, achieved by harmonizing relationships with the entities of external influence and optimizing the internal system processes, thus enabling efficient function as well as development by means of an adaptation mechanism. A number of approaches to understanding the substance of the above concept has been allocated and their main characteristics have been provided. The need to study the specifics of interaction of banking institutions with the external environment in the context of interaction between the State agents and market actors has been underlined. Features of formation of the term of «system» have been defined, three main groups of approaches to interpretation of the term have been provided. A author’s own definition of the concept of «economic security system of bank» has been proposed. A concrete definition of principles for building an economic security system of bank has been provided.

  4. Indiana University Theoretical Particle Physics Group. Final report, December 1, 1970-October 31, 1983

    Hendry, A.W.; Lichtenberg, D.B.; Weingarten, D.H.

    1983-01-01

    We have carried out a broad program of research to understand aspects of the interactions of nature on both theoretical and phenomenological levels. Our research has led to the publication of about 130 papers; these paper are listed. We also have worked closely with the members of the high energy experimental group to give them theoretical support and to help in interpretation of their experiments. A brief summary of accomplishments is given

  5. Distinguishing prognostic and predictive biomarkers: An information theoretic approach.

    Sechidis, Konstantinos; Papangelou, Konstantinos; Metcalfe, Paul D; Svensson, David; Weatherall, James; Brown, Gavin

    2018-05-02

    The identification of biomarkers to support decision-making is central to personalised medicine, in both clinical and research scenarios. The challenge can be seen in two halves: identifying predictive markers, which guide the development/use of tailored therapies; and identifying prognostic markers, which guide other aspects of care and clinical trial planning, i.e. prognostic markers can be considered as covariates for stratification. Mistakenly assuming a biomarker to be predictive, when it is in fact largely prognostic (and vice-versa) is highly undesirable, and can result in financial, ethical and personal consequences. We present a framework for data-driven ranking of biomarkers on their prognostic/predictive strength, using a novel information theoretic method. This approach provides a natural algebra to discuss and quantify the individual predictive and prognostic strength, in a self-consistent mathematical framework. Our contribution is a novel procedure, INFO+, which naturally distinguishes the prognostic vs predictive role of each biomarker and handles higher order interactions. In a comprehensive empirical evaluation INFO+ outperforms more complex methods, most notably when noise factors dominate, and biomarkers are likely to be falsely identified as predictive, when in fact they are just strongly prognostic. Furthermore, we show that our methods can be 1-3 orders of magnitude faster than competitors, making it useful for biomarker discovery in 'big data' scenarios. Finally, we apply our methods to identify predictive biomarkers on two real clinical trials, and introduce a new graphical representation that provides greater insight into the prognostic and predictive strength of each biomarker. R implementations of the suggested methods are available at https://github.com/sechidis. konstantinos.sechidis@manchester.ac.uk. Supplementary data are available at Bioinformatics online.

  6. Prospecting theoretical approaches to understand internationalization of creative economy firms

    Sílvio Luís de Vasconcellos

    2017-12-01

    Full Text Available We argue that the internationalization process of firms in the creative economy has particular aspects that distinguish it from internationalization of firms in traditional economic sectors. We explore ways in which the international business literature might be helpful for understanding how internationalization takes place in firms whose core business is creation of ideas. We conducted a case study using a focus group technique to investigate a creative economy firm specialized in computer graphics. The firm already does business internationally as a producer of electronic mockup models, but is transitioning to the computer-generated video production industry. Our results suggest that behavioral approaches to international business related to entrepreneurship, as well as country origin effects and networks theory could be useful to expanding knowledge about the internationalization process in such firms, in which creativity is a critical resource.

  7. SUSTAINABLE TOURISM AND ITS FORMS - A THEORETICAL APPROACH

    Bac Dorin

    2013-07-01

    Full Text Available From the second half of the twentieth century, the importance of the tourism industry to the world economy continued to grow, reaching today impressive figures: receipts of almost $ 1,000 billion and direct employment for over 70 million people (WTTC 2012, without taking into account the multiplier effect (according to the same statistics of WTTC, if considering the multiplier effect, the values are: $ 5,990 billion in tourism receipts, and 253.5 million jobs. We can say that tourism: has a higher capacity to generate and distribute incomes compared to other sectors; has a high multiplier effect; determines a high level of consumption of varied products and services. In this context, voices began to emerge, which presented the problems and challenges generated by the tourism activity. Many regions are facing real problems generated by tourism entrepreneurs and tourists who visit the community. Therefore, at the end of the last century, there were authors who sought to define a new form of tourism, which eliminated the negative impacts and increased the positive ones. As a generic term they used alternative tourism, but because of the ambiguity of the term, they tried to find a more precise term, which would define the concept easier. Thus emerged: ecotourism, rural tourism, Pro Poor Tourism etc.. All these forms have been introduced under the umbrella concept of sustainable tourism. In the present paper we will take a theoretical approach, in order to present some forms of sustainable tourism. During our research we covered the ideas and concepts promoted by several authors and academics but also some international organizations with focus on tourism. We considered these forms of tourism, as they respect all the rules of sustainable tourism and some of them have great potential to grow in both developed and emerging countries. The forms of sustainable tourism we identified are: ecotourism, pro-poor tourism, volunteer tourism and slow tourism. In

  8. Renormalization group approach to superfluid neutron matter

    Hebeler, K.

    2007-06-06

    In the present thesis superfluid many-fermion systems are investigated in the framework of the Renormalization Group (RG). Starting from an experimentally determined two-body interaction this scheme provides a microscopic approach to strongly correlated many-body systems at low temperatures. The fundamental objects under investigation are the two-point and the four-point vertex functions. We show that explicit results for simple separable interactions on BCS-level can be reproduced in the RG framework to high accuracy. Furthermore the RG approach can immediately be applied to general realistic interaction models. In particular, we show how the complexity of the many-body problem can be reduced systematically by combining different RG schemes. Apart from technical convenience the RG framework has conceptual advantage that correlations beyond the BCS level can be incorporated in the flow equations in a systematic way. In this case however the flow equations are no more explicit equations like at BCS level but instead a coupled set of implicit equations. We show on the basis of explicit calculations for the single-channel case the efficacy of an iterative approach to this system. The generalization of this strategy provides a promising strategy for a non-perturbative treatment of the coupled channel problem. By the coupling of the flow equations of the two-point and four-point vertex self-consistency on the one-body level is guaranteed at every cutoff scale. (orig.)

  9. Resilience or Flexibility– A Theoretical Approach on Romanian Development Regions

    Roxana Voicu – Dorobanțu

    2015-09-01

    Full Text Available The paper describes a theoretical contextualization of flexibility, sustainability, durability and resilience, in the context of the sustainable development goals. The main purpose is to identify the theoretical handles that may be used in the creation of a flexibility indicator. Thus, research questions related to the theoretical differentiation between durable and sustainable, flexible and resilient are answered. Further on, the paper describes the situation of the Romanian regions in terms of development indicators, based on Eurostat data, as a premise for further research on the possibility of their leapfrogging. This work was financially supported through the project “Routes of academic excellence in doctoral and post-doctoral research- REACH” co-financed through the European Social Fund, by Sectoral Operational Programme Human Resources Development 2007-2013, contract no POSDRU/59/1.5/S/137926.

  10. Game-theoretic interference coordination approaches for dynamic spectrum access

    Xu, Yuhua

    2016-01-01

    Written by experts in the field, this book is based on recent research findings in dynamic spectrum access for cognitive radio networks. It establishes a game-theoretic framework and presents cutting-edge technologies for distributed interference coordination. With game-theoretic formulation and the designed distributed learning algorithms, it provides insights into the interactions between multiple decision-makers and the converging stable states. Researchers, scientists and engineers in the field of cognitive radio networks will benefit from the book, which provides valuable information, useful methods and practical algorithms for use in emerging 5G wireless communication.

  11. Theoretical and methodological approaches to economic competitiveness (Part I

    Macari Vadim

    2013-01-01

    Full Text Available The article is based on study of several representative bibliographical sources,it is tried to examine, to order from logical and scientific point of view some of the most common theoretical and methodological understandings of the essence, definition, phenomenon, types, haracteristics and indices of economic competitiveness.

  12. Theoretical and methodological approaches to economic competitiveness (part II

    Macari Vadim

    2013-02-01

    Full Text Available This article, on the basis of the study of many representative bibliographic sources, examines and tries to order from logical and scientific point of view some of the most common theoretical and methodological treatments of the essence, definition, phenomenon, types, characteristics and indices of economic competitiveness.

  13. THEORETICAL AND METHODOLOGICAL APPROACHES TO ECONOMIC COMPETITIVENESS (Part II

    Vadim MACARI

    2013-02-01

    Full Text Available This article, on the basis of the study of many representative bibliographic sources, examines and tries to order from logical and scientific point of view some of the most common theoretical and methodological treatments of the essence, definition, phenomenon, types, characteristics and indices of economic competitiveness.

  14. THEORETICAL AND METHODOLOGICAL APPROACHES TO ECONOMIC COMPETITIVENESS (Part I

    Vadim MACARI

    2013-01-01

    Full Text Available The article is based on study of several representative bibliographical sources,it is tried to examine, to order from logical and scientific point of view some of the most common theoretical and methodological understandings of the essence, definition, phenomenon, types, characteristics and indices of economic competitiveness.

  15. Group-theoretical interpretation of the Korteweg-de Vries type equations

    Berezin, F.A.; Perelomov, A.M.

    1978-01-01

    The Korteweg-de Vries equation is studied within the group-theoretical framework. Analogous equations are obtained for which the many-dimensional Schroedinger equation (with nonlocal potential) plays the same role as the one-dimensional Schroedinger equation does in the theory of the Korteweg-de Vries equation

  16. Group theoretical symmetries and generalized Bäcklund transformations for integrable systems

    Haak, Guido

    1994-05-01

    A notion of symmetry for 1+1-dimensional integrable systems is presented which is consistent with their group theoretic description. It is shown how a group symmetry may be used together with a dynamical reduction to produce new generalizations of the Bäcklund transformation for the Korteweg-de Vries equation to its SL(n,C) generalization. An additional application to the relativistic invariance of the Leznov-Saveliev systems is given.

  17. Non-commutative cryptography and complexity of group-theoretic problems

    Myasnikov, Alexei; Ushakov, Alexander

    2011-01-01

    This book is about relations between three different areas of mathematics and theoretical computer science: combinatorial group theory, cryptography, and complexity theory. It explores how non-commutative (infinite) groups, which are typically studied in combinatorial group theory, can be used in public-key cryptography. It also shows that there is remarkable feedback from cryptography to combinatorial group theory because some of the problems motivated by cryptography appear to be new to group theory, and they open many interesting research avenues within group theory. In particular, a lot of emphasis in the book is put on studying search problems, as compared to decision problems traditionally studied in combinatorial group theory. Then, complexity theory, notably generic-case complexity of algorithms, is employed for cryptanalysis of various cryptographic protocols based on infinite groups, and the ideas and machinery from the theory of generic-case complexity are used to study asymptotically dominant prop...

  18. Nonlinear relativistic plasma resonance: Renormalization group approach

    Metelskii, I. I., E-mail: metelski@lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Kovalev, V. F., E-mail: vfkvvfkv@gmail.com [Dukhov All-Russian Research Institute of Automatics (Russian Federation); Bychenkov, V. Yu., E-mail: bychenk@lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2017-02-15

    An analytical solution to the nonlinear set of equations describing the electron dynamics and electric field structure in the vicinity of the critical density in a nonuniform plasma is constructed using the renormalization group approach with allowance for relativistic effects of electron motion. It is demonstrated that the obtained solution describes two regimes of plasma oscillations in the vicinity of the plasma resonance— stationary and nonstationary. For the stationary regime, the spatiotemporal and spectral characteristics of the resonantly enhanced electric field are investigated in detail and the effect of the relativistic nonlinearity on the spatial localization of the energy of the plasma relativistic field is considered. The applicability limits of the obtained solution, which are determined by the conditions of plasma wave breaking in the vicinity of the resonance, are established and analyzed in detail for typical laser and plasma parameters. The applicability limits of the earlier developed nonrelativistic theories are refined.

  19. Renormalization group approach in the turbulence theory

    Adzhemyan, L.Ts.; Vasil'ev, A.N.; Pis'mak, Yu.M.

    1983-01-01

    In the framework of the renormalization groUp approach in the turbulence theory sUggested in another paper, the problem of renormalization and evaluation of critical dimensions of composite operators is discussed. Renormalization of a system of operators of canonical dimension equal to 4, including the operator F=phiΔphi (where phi is the velocity field), is considered. It is shown that the critical dimension Δsub(F)=0. The appendice includes the brief proofs of two theorems: 1) the theorem on the equivalence between the arbitrary stochastic problem and quantum field theory; 2) the theorem which determines the reduction of Green functions of the stochastic problem to the hypersurface of coinciding times

  20. Scientific-theoretical research approach to practical theology in ...

    All of them work with practical theological hermeneutics. The basic hermeneutic approach of Daniël Louw is widened with an integrated approach by Richard R. Osmer in which practical theology as a hermeneutic discipline also includes the empirical aspect which the action theory approach has contributed to the ...

  1. Nonperturbative Renormalization Group Approach to Polymerized Membranes

    Essafi, Karim; Kownacki, Jean-Philippe; Mouhanna, Dominique

    2014-03-01

    Membranes or membrane-like materials play an important role in many fields ranging from biology to physics. These systems form a very rich domain in statistical physics. The interplay between geometry and thermal fluctuations lead to exciting phases such flat, tubular and disordered flat phases. Roughly speaking, membranes can be divided into two group: fluid membranes in which the molecules are free to diffuse and thus no shear modulus. On the other hand, in polymerized membranes the connectivity is fixed which leads to elastic forces. This difference between fluid and polymerized membranes leads to a difference in their critical behaviour. For instance, fluid membranes are always crumpled, whereas polymerized membranes exhibit a phase transition between a crumpled phase and a flat phase. In this talk, I will focus only on polymerized phantom, i.e. non-self-avoiding, membranes. The critical behaviour of both isotropic and anisotropic polymerized membranes are studied using a nonperturbative renormalization group approach (NPRG). This allows for the investigation of the phase transitions and the low temperature flat phase in any internal dimension D and embedding d. Interestingly, graphene behaves just as a polymerized membrane in its flat phase.

  2. THEORETICAL AND METHODOLOGICAL APPROACHES TO REGIONAL COMPETITION INVESTIGATION

    A.I. Tatarkin

    2006-03-01

    Full Text Available The article is dedicated to theoretical-methodological issues of regional economy competitiveness investigation. Economic essence of regional competitiveness is analyzed, its definition is given. The factors that determine relations of competition on medium and macrolevels are proved. The basic differences between world-economical and inter-regional communications are formulated. The specific features of globalization processes as form of competitive struggle are considered.

  3. Representing electrons a biographical approach to theoretical entities

    Arabatzis, Theodore

    2006-01-01

    Both a history and a metahistory, Representing Electrons focuses on the development of various theoretical representations of electrons from the late 1890s to 1925 and the methodological problems associated with writing about unobservable scientific entities. Using the electron-or rather its representation-as a historical actor, Theodore Arabatzis illustrates the emergence and gradual consolidation of its representation in physics, its career throughout old quantum theory, and its appropriation and reinterpretation by chemists. As Arabatzis develops this novel biographical

  4. We need theoretical physics approaches to study living systems

    Blagoev, Krastan B.; Shukla, Kamal; affil="3" >Herbert Levine,

    2013-08-01

    Living systems, as created initially by the transition from assemblies of large molecules to self-reproducing information-rich cells, have for centuries been studied via the empirical toolkit of biology. This has been a highly successful enterprise, bringing us from the vague non-scientific notions of vitalism to the modern appreciation of the biophysical and biochemical bases of life. Yet, the truly mind-boggling complexity of even the simplest self-sufficient cells, let alone the emergence of multicellular organisms, of brain and consciousness, and to ecological communities and human civilizations, calls out for a complementary approach. In this editorial, we propose that theoretical physics can play an essential role in making sense of living matter. When faced with a highly complex system, a physicist builds simplified models. Quoting Philip W Anderson's Nobel prize address, 'the art of model-building is the exclusion of real but irrelevant parts of the problem and entails hazards for the builder and the reader. The builder may leave out something genuinely relevant and the reader, armed with too sophisticated an experimental probe, may take literally a schematized model. Very often such a simplified model throws more light on the real working of nature....' In his formulation, the job of a theorist is to get at the crux of the system by ignoring details and yet to find a testable consequence of the resulting simple picture. This is rather different than the predilection of the applied mathematician who wants to include all the known details in the hope of a quantitative simulacrum of reality. These efforts may be practically useful, but do not usually lead to increased understanding. To illustrate how this works, we can look at a non-living example of complex behavior that was afforded by spatiotemporal patterning in the Belousov-Zhabotinsky reaction [1]. Physicists who worked on this system did not attempt to determine all the relevant chemical intermediates

  5. How do small groups make decisions? : A theoretical framework to inform the implementation and study of clinical competency committees.

    Chahine, Saad; Cristancho, Sayra; Padgett, Jessica; Lingard, Lorelei

    2017-06-01

    In the competency-based medical education (CBME) approach, clinical competency committees are responsible for making decisions about trainees' competence. However, we currently lack a theoretical model for group decision-making to inform this emerging assessment phenomenon. This paper proposes an organizing framework to study and guide the decision-making processes of clinical competency committees.This is an explanatory, non-exhaustive review, tailored to identify relevant theoretical and evidence-based papers related to small group decision-making. The search was conducted using Google Scholar, Web of Science, MEDLINE, ERIC, and PsycINFO for relevant literature. Using a thematic analysis, two researchers (SC & JP) met four times between April-June 2016 to consolidate the literature included in this review.Three theoretical orientations towards group decision-making emerged from the review: schema, constructivist, and social influence. Schema orientations focus on how groups use algorithms for decision-making. Constructivist orientations focus on how groups construct their shared understanding. Social influence orientations focus on how individual members influence the group's perspective on a decision. Moderators of decision-making relevant to all orientations include: guidelines, stressors, authority, and leadership.Clinical competency committees are the mechanisms by which groups of clinicians will be in charge of interpreting multiple assessment data points and coming to a shared decision about trainee competence. The way in which these committees make decisions can have huge implications for trainee progression and, ultimately, patient care. Therefore, there is a pressing need to build the science of how such group decision-making works in practice. This synthesis suggests a preliminary organizing framework that can be used in the implementation and study of clinical competency committees.

  6. Strength of wood versus rate of testing - A theoretical approach

    Nielsen, Lauge Fuglsang

    2007-01-01

    Strength of wood is normally measured in ramp load experiments. Experience shows that strength increases with increasing rate of testing. This feature is considered theoretically in this paper. It is shown that the influence of testing rate is a phenomenon, which depends on the quality...... of the considered wood. Low quality wood shows lesser influence of testing rate. This observation agrees with the well-known statement made by Borg Madsen that weak wood subjected to a constant load, has a longer lifetime than strong wood. In general, the influence of testing rate on strength increases...

  7. Theoretical approaches to digital services and digital democracy

    Hoff, Jens Villiam; Scheele, Christian Elling

    2014-01-01

    The purpose of this paper is to develop a theoretical framework, which can be used in the analysis of all types of (political-administrative) web applications. Through a discussion and criticism of social construction of technology (SCOT), an earlier version of this model based on new medium theory...... are translated into specific (political-administrative) practices, and how these practices are produced through the interplay between discourses, actors and technology. However, the new version places practices more firmly at the centre of the model, as practices, following Reckwitz, is seen as the enactment...

  8. A Representation-Theoretic Approach to Reversible Computation with Applications

    Maniotis, Andreas Milton

    Reversible computing is a sub-discipline of computer science that helps to understand the foundations of the interplay between physics, algebra, and logic in the context of computation. Its subjects of study are computational devices and abstract models of computation that satisfy the constraint ......, there is still no uniform and consistent theory that is general in the sense of giving a model-independent account to the field....... of information conservation. Such machine models, which are known as reversible models of computation, have been examined both from a theoretical perspective and from an engineering perspective. While a bundle of many isolated successful findings and applications concerning reversible computing exists...

  9. Group theoretical methods in physics. [Tuebingen, July 18-22, 1977

    Kramer, P; Rieckers, A

    1978-01-01

    This volume comprises the proceedings of the 6th International Colloquium on Group Theoretical Methods in Physics, held at Tuebingen in July 1977. Invited papers were presented on the following topics: supersymmetry and graded Lie algebras; concepts of order and disorder arising from molecular physics; symplectic structures and many-body physics; symmetry breaking in statistical mechanics and field theory; automata and systems as examples of applied (semi-) group theory; renormalization group; and gauge theories. Summaries are given of the contributed papers, which can be grouped as follows: supersymmetry, symmetry in particles and relativistic physics; symmetry in molecular and solid state physics; broken symmetry and phase transitions; structure of groups and dynamical systems; representations of groups and Lie algebras; and general symmetries, quantization. Those individual papers in scope for the TIC data base are being entered from ATOMINDEX tapes. (RWR)

  10. The production of scientific videos: a theoretical approach

    Carlos Ernesto Gavilondo Rodriguez

    2016-12-01

    Full Text Available The article presents the results of theoretical research on the production of scientific videos and its application to the teaching-learning process carried out in schools in the city of Guayaquil, Ecuador. It is located within the production line and Audiovisual Communication. Creation of scientific videos, from the Communication major with a concentration in audiovisual production and multimedia of the Salesian Polytechnic University. For the realization of the article it was necessary to use key terms that helped subsequently to data collection. used terms such as: audiovisual production, understood as the production of content for audiovisual media; the following term used audiovisual communication is recognized as the process in which there is an exchange of messages through an audible and / or visual system; and the last term we use is scientifically video, which is one that uses audiovisual resources to obtain relevant and reliable information.As part of the theoretical results a methodological proposal for the video production is presented for educational purposes. In conclusion set out, first, that from the communicative statement in recent times, current social relations, constitute a successful context of possibilities shown to education to generate meeting points between the world of the everyday and the knowledge. Another indicator validated as part of the investigation, is that teachers surveyed use the potential of the audiovisual media, and supported them, deploy alternatives for use. 

  11. Field-theoretic approach to fluctuation effects in neural networks

    Buice, Michael A.; Cowan, Jack D.

    2007-01-01

    A well-defined stochastic theory for neural activity, which permits the calculation of arbitrary statistical moments and equations governing them, is a potentially valuable tool for theoretical neuroscience. We produce such a theory by analyzing the dynamics of neural activity using field theoretic methods for nonequilibrium statistical processes. Assuming that neural network activity is Markovian, we construct the effective spike model, which describes both neural fluctuations and response. This analysis leads to a systematic expansion of corrections to mean field theory, which for the effective spike model is a simple version of the Wilson-Cowan equation. We argue that neural activity governed by this model exhibits a dynamical phase transition which is in the universality class of directed percolation. More general models (which may incorporate refractoriness) can exhibit other universality classes, such as dynamic isotropic percolation. Because of the extremely high connectivity in typical networks, it is expected that higher-order terms in the systematic expansion are small for experimentally accessible measurements, and thus, consistent with measurements in neocortical slice preparations, we expect mean field exponents for the transition. We provide a quantitative criterion for the relative magnitude of each term in the systematic expansion, analogous to the Ginsburg criterion. Experimental identification of dynamic universality classes in vivo is an outstanding and important question for neuroscience

  12. When the Mannequin Dies, Creation and Exploration of a Theoretical Framework Using a Mixed Methods Approach.

    Tripathy, Shreepada; Miller, Karen H; Berkenbosch, John W; McKinley, Tara F; Boland, Kimberly A; Brown, Seth A; Calhoun, Aaron W

    2016-06-01

    Controversy exists in the simulation community as to the emotional and educational ramifications of mannequin death due to learner action or inaction. No theoretical framework to guide future investigations of learner actions currently exists. The purpose of our study was to generate a model of the learner experience of mannequin death using a mixed methods approach. The study consisted of an initial focus group phase composed of 11 learners who had previously experienced mannequin death due to action or inaction on the part of learners as defined by Leighton (Clin Simul Nurs. 2009;5(2):e59-e62). Transcripts were analyzed using grounded theory to generate a list of relevant themes that were further organized into a theoretical framework. With the use of this framework, a survey was generated and distributed to additional learners who had experienced mannequin death due to action or inaction. Results were analyzed using a mixed methods approach. Forty-one clinicians completed the survey. A correlation was found between the emotional experience of mannequin death and degree of presession anxiety (P framework. Using the previous approach, we created a model of the effect of mannequin death on the educational and psychological state of learners. We offer the final model as a guide to future research regarding the learner experience of mannequin death.

  13. A new theoretical approach to adsorption desorption behavior of Ga on GaAs surfaces

    Kangawa, Y.; Ito, T.; Taguchi, A.; Shiraishi, K.; Ohachi, T.

    2001-11-01

    We propose a new theoretical approach for studying adsorption-desorption behavior of atoms on semiconductor surfaces. The new theoretical approach based on the ab initio calculations incorporates the free energy of gas phase; therefore we can calculate how adsorption and desorption depends on growth temperature and beam equivalent pressure (BEP). The versatility of the new theoretical approach was confirmed by the calculation of Ga adsorption-desorption transition temperatures and transition BEPs on the GaAs(0 0 1)-(4×2)β2 Ga-rich surface. This new approach is feasible to predict how adsorption and desorption depend on the growth conditions.

  14. A Game-Theoretical Approach to Multimedia Social Networks Security

    Liu, Enqiang; Liu, Zengliang; Shao, Fei; Zhang, Zhiyong

    2014-01-01

    The contents access and sharing in multimedia social networks (MSNs) mainly rely on access control models and mechanisms. Simple adoptions of security policies in the traditional access control model cannot effectively establish a trust relationship among parties. This paper proposed a novel two-party trust architecture (TPTA) to apply in a generic MSN scenario. According to the architecture, security policies are adopted through game-theoretic analyses and decisions. Based on formalized utilities of security policies and security rules, the choice of security policies in content access is described as a game between the content provider and the content requester. By the game method for the combination of security policies utility and its influences on each party's benefits, the Nash equilibrium is achieved, that is, an optimal and stable combination of security policies, to establish and enhance trust among stakeholders. PMID:24977226

  15. A theoretical approach for energy saving in industrial steam boilers

    Sabry, T.I.; Mohamed, N.H.; Elghonimy, A.M.

    1993-01-01

    Optimization of the performance characteristics of such a steam boiler has been analyzed theoretically. Suitable thermodynamic relations have been utilized here to construct a computer model that would carry out the boiler performance characteristics at different operating parameters (e.g.; amount of excess air, fuel type, rate of blowdown preheating of combustion air and flow gases temperature). The results demonstrate that this computer model is to be used successfully in selecting the different operating parameters of the steam boiler at variant loads considering the best economical operation. Besides, this model can be used to investigate the sensitivity of the performance characteristics to the deviation of the boiler operating parameters from their optimum values. It was found also that changing the operating parameters beside the type of fuel in a boiler affects its performance characteristics. 3 figs

  16. Theoretical information measurement in nonrelativistic time-dependent approach

    Najafizade, S. A.; Hassanabadi, H.; Zarrinkamar, S.

    2018-02-01

    The information-theoretic measures of time-dependent Schrödinger equation are investigated via the Shannon information entropy, variance and local Fisher quantities. In our calculations, we consider the two first states n = 0,1 and obtain the position Sx (t) and momentum Sp (t) Shannon entropies as well as Fisher information Ix (t) in position and momentum Ip (t) spaces. Using the Fourier transformed wave function, we obtain the results in momentum space. Some interesting features of the information entropy densities ρs (x,t) and γs (p,t), as well as the probability densities ρ (x,t) and γ (p,t) for time-dependent states are demonstrated. We establish a general relation between variance and Fisher's information. The Bialynicki-Birula-Mycielski inequality is tested and verified for the states n = 0,1.

  17. A game-theoretic approach to donor kidney sharing.

    O'Brien, B J

    1988-01-01

    Graft survival in renal transplantation is a function, amongst other things, of the degree of histocompatibility lymphocyte-A (HLA) tissue matching achieved between donor and recipient. Yet a donor procured at centre A might match a transplant candidate at centre B and vice versa. This raises the question of whether, and under what circumstances, surgeons will offer and exchange donor kidneys and gain from such trade in terms of graft survival. We analyse the problem in a game-theoretic framework where the choice of strategy 'to offer or not?' is evaluated in the context of the uncertainty of reciprocation by the other player(s) in the game. The equilibrium solution to a number of variations of the game is predicted to be non-cooperation resulting in collectively sub-optimal graft survival rates. Some policy options for improving cooperation are considered including exchange incentives and coercive measures.

  18. A theoretical approach on controlling agricultural pest by biological controls.

    Mondal, Prasanta Kumar; Jana, Soovoojeet; Kar, T K

    2014-03-01

    In this paper we propose and analyze a prey-predator type dynamical system for pest control where prey population is treated as the pest. We consider two classes for the pest namely susceptible pest and infected pest and the predator population is the natural enemy of the pest. We also consider average delay for both the predation rate i.e. predation to the susceptible pest and infected pest. Considering a subsystem of original system in the absence of infection, we analyze the existence of all possible non-negative equilibria and their stability criteria for both the subsystem as well as the original system. We present the conditions for transcritical bifurcation and Hopf bifurcation in the disease free system. The theoretical evaluations are demonstrated through numerical simulations.

  19. A Theoretical Approach to Engineering a New Enzyme

    Anderson, Greg; Gomatam, Ravi; Behera, Raghu N.

    2016-01-01

    Density function theory, a subfield of quantum mechanics (QM), in combination with molecular mechanics (MM) has opened the way to engineer new artificial enzymes. Herein, we report theoretical calculations done using QM/MM to examine whether the regioselectivity and rate of chlorination of the enzyme chloroperoxidase can be improved by replacing the vanadium of this enzyme with niobium through dialysis. Our calculations show that a niobium substituted chloroperoxidase will be able to enter the initial steps of the catalytic cycle for chlorination. Although the protonation state of the niobium substituted enzyme is calculated to be different from than that of the natural vanadium substituted enzyme, our calculations show that the catalytic cycle can still proceed forward. Using natural bond orbitals, we analyse the electronic differences between the niobium substituted enzyme and the natural enzyme. We conclude by briefly examining how good of a model QM/MM provides for understanding the mechanism of catalysis of chloroperoxidase. (paper)

  20. Laser debonding of ceramic orthodontic brackets: a theoretical approach

    Kearney, Kristine L.; Marangoni, Roy D.; Rickabaugh, Jeff L.

    1992-06-01

    Ceramic brackets are an esthetic substitute for conventional stainless steel brackets in orthodontic patients. However, ceramic brackets are more brittle and have higher bond strengths which can lead to bracket breakage and enamel damage during debonding. It has been demonstrated that various lasers can facilitate ceramic bracket removal. One mechanism with the laser is through the softening of the bracket adhesive. The high energy density from the laser on the bracket and adhesive can have a resultant deleterious thermal effect on the pulp of the tooth which may lead to pulpal death. A theoretical computer model of bracket, adhesive, enamel and dentin has been generated for predicting heat flow through this system. Heat fluxes at varying intensities and modes have been input into the program and the resultant temperatures at various points or nodes were determined. Further pursuit should lead to optimum parameters for laser debonding which would have minimal effects on the pulp.

  1. Tourism and international business: The theoretical approach and practical experiences

    Jovičić Dobrica

    2011-01-01

    Full Text Available The paper discusses the relationships between tourism and international business. The research is based upon combining various theoretical concepts, significant empirical experiences and own attitudes of the authors. The key conclusion of the paper is that, despite of the partial progress in understanding tourism businesses, the relationships between tourism and international business need additional stimulus. In other words, more complete research in the related domains is needed in future. Any understanding of tourism is inadequate without appreciating the contributions that international business might bring, yet at the same time international business is incomplete in its coverage of international trade unless tourism is considered. The consumption-driven agenda of much tourism research has been favoured over supply-side discourses of the production process it self. That is why the role of major transnational companies, setting the trends that other types of firms in the tourism sector follow is focused in the paper.

  2. Interaction of paracetamol and 125I-paracetamol with surface groups of activated carbon. Theoretical and experimental study

    Daniel Hernandez-Valdes; Ulises Jauregui-Haza; Carlos Enriquez-Victorero; Melvin Arias

    2015-01-01

    The selection of activated carbon (AC) filters for water decontamination is currently carried out empirically. The low concentrations of drugs in the environment make the radioisotope labeling a valuable tool for physical and chemical studies of the adsorption process. A theoretical study of paracetamol and 125 I-paracetamol adsorption onto AC was performed to evaluate the interactions between pollutants and surface groups (SG) of AC. Paracetamol was labeled with 125 I and adsorption isotherms were obtained using radioanalytical and spectrophotometric techniques. The radioanalytical method overestimates the paracetamol adsorption. The validity of the chosen approach for qualitative assessment of SG influence over the adsorption process was demonstrated. (author)

  3. Social self-esteem: theoretical and methodological approaches to research

    Usova E.N.

    2017-09-01

    Full Text Available The perspective of the analysis of the phenomenon of the social well-being of patients with chronic diseases from the standpoint of the sociology of medicine is proved. Modern approaches to the study of social well-being within the framework of sociological and psychological approaches are singled out. The importance of studying the levels of social well-being (institutional and individual is presented to explain the individual's chosen strategies of behavior in the disease situation. The vectors of operationalization of the category of social well-being within the sociology of medicine are indicated.

  4. Group problem solving as a different participatory approach to Citizenship Education.

    Guérin, Laurence

    2017-01-01

    Purpose: The main goal of this article is to define and justify group problem solving as an approach to citizenship education. It is demonstrated that the choice of theoretical framework of democracy has consequences for the chosen learning goals, educational approach and learning activities. The

  5. Group-theoretical aspects of the discrete sine-Gordon equation

    Orfanidis, S.J.

    1980-01-01

    The group-theoretical interpretation of the sine-Gordon equation in terms of connection forms on fiber bundles is extended to the discrete case. Solutions of the discrete sine-Gordon equation induce surfaces on a lattice in the SU(2) group space. The inverse scattering representation, expressing the parallel transport of fibers, is implemented by means of finite rotations. Discrete Baecklund transformations are realized as gauge transformations. The three-dimensional inverse scattering representation is used to derive a discrete nonlinear sigma model, and the corresponding Baecklund transformation and Pohlmeyer's R transformation are constructed

  6. Photodynamic therapy: Theoretical and experimental approaches to dosimetry

    Wang, Ken Kang-Hsin

    Singlet oxygen (1O2) is the major cytotoxic species generated during photodynamic therapy (PDT), and 1O 2 reactions with biological targets define the photodynamic dose at the most fundamental level. We have developed a theoretical model for rigorously describing the spatial and temporal dynamics of oxygen (3O 2) consumption and transport and microscopic 1O 2 dose deposition during PDT in vivo. Using experimentally established physiological and photophysical parameters, the mathematical model allows computation of the dynamic variation of hemoglobin-3O 2 saturation within vessels, irreversible photosensitizer degradation due to photobleaching, therapy-induced blood flow decrease and the microscopic distributions of 3O2 and 1O 2 dose deposition under various irradiation conditions. mTHPC, a promising photosensitizer for PDT, is approved in Europe for the palliative treatment of head and neck cancer. Using the theoretical model and informed by intratumor sensitizer concentrations and distributions, we calculated photodynamic dose depositions for mTHPC-PDT. Our results demonstrate that the 1O 2 dose to the tumor volume does not track even qualitatively with long-term tumor responses. Thus, in this evaluation of mTHPC-PDT, any PDT dose metric that is proportional to singlet oxygen creation and/or deposition would fail to predict the tumor response. In situations like this one, other reporters of biological response to therapy would be necessary. In addition to the case study of mTHPC-PDT, we also use the mathematical model to simulate clinical photobleaching data, informed by a possible blood flow reduction during treatment. In a recently completed clinical trial at Roswell Park Cancer Institute, patients with superficial basal cell carcinoma received topical application of 5-aminolevulinic acid (ALA) and were irradiated with 633 nm light at 10-150 mW cm-2 . Protoporphyrin IX (PpIX) photobleaching in the lesion and the adjacent perilesion normal margin was monitored by

  7. THEORETICAL APPROACHES TO THE DEFINITION OF THE "INFORMATION RESOURCE"

    I. Netreba

    2014-01-01

    Existing approaches to determining the nature of the category "information resource" are detailed and systematized. The relationships between the categories "information resource", "information technology", "information management system" are revealed. Determined the importance of information resources for the production process at the enterprise.

  8. Game-theoretic approaches to optimal risk sharing

    Boonen, T.J.

    2014-01-01

    This Ph.D. thesis studies optimal risk capital allocation and optimal risk sharing. The first chapter deals with the problem of optimally allocating risk capital across divisions within a financial institution. To do so, an asymptotic approach is used to generalize the well-studied Aumann-Shapley

  9. Fuzzy set theoretic approach to fault tree analysis | Tyagi ...

    This approach can be widely used to improve the reliability and to reduce the operating cost of a system. The proposed techniques are discussed and illustrated by taking an example of a nuclear power plant. Keywords: Fault tree, Triangular and Trapezoidal fuzzy number, Fuzzy importance, Ranking of fuzzy numbers ...

  10. Towards a capability approach to child growth : A theoretical framework

    Haisma, Hinke; Yousefzadeh Faal Daghati, Sepideh; Boele Van Hensbroek, Pieter

    Child malnutrition is an important cause of under-five mortality and morbidity around the globe. Despite the partial success of (inter)national efforts to reduce child mortality, under-five mortality rates continue to be high. The multidimensional approaches of the Sustainable Development Goals may

  11. A New Approach to Group Learning

    Parsons, Jerry

    1976-01-01

    To help teachers plan strategy for working with a learning group, 12 factors affecting a learning group are discussed and a series of check points are identified as criteria for evaluation. Concepts and principles of group dynamics are drawn from sociology and the work of Carl Rogers. (Author/AJ)

  12. Hydrogen storage in lithium hydride: A theoretical approach

    Banger, Suman; Nayak, Vikas; Verma, U. P.

    2018-04-01

    First principles calculations have been carried out to analyze structural stability of lithium hydride (LiH) in NaCl phase using the full potential linearized augmented plane wave (FP-LAPW) method within the framework of density functional theory (DFT). Calculations have been extended to physiosorbed H-atom compounds LiH·H2, LiH·3H2 and LiH·4H2. The obtained results are discussed in the paper. The results for LiH are in excellent agreement with earlier reported data. The obtained direct energy band gap of LiH is 3.0 eV which is in excellent agreement with earlier reported theoretical band gap. The electronic band structure plots of the hydrogen adsorbed compounds show metallic behavior. The elastic constants, anisotropy factor, shear modulus, Young's modulus, Poisson's ratio and cohesive energies of all the compounds are calculated. Calculation of the optical spectra such as the real and imaginary parts of dielectric function, optical reflectivity, absorption coefficient, optical conductivity, refractive index, extinction coefficient and electron energy loss are performed for the energy range 0-15 eV. The obtained results for LiH·H2, LiH·3H2 and LiH·4H2, are reported for the first time. This study has been made in search of materials for hydrogen storage. It is concluded that LiH is a promising material for hydrogen storage.

  13. Exploring Job Satisfaction of Nursing Faculty: Theoretical Approaches.

    Wang, Yingchen; Liesveld, Judy

    2015-01-01

    The Future of Nursing report identified the shortage of nursing faculty as 1 of the barriers to nursing education. In light of this, it is becoming increasingly important to understand the work-life of nursing faculty. The current research focused on job satisfaction of nursing faculty from 4 theoretical perspectives: human capital theory, which emphasizes the expected monetary and nonmonetary returns for any career choices; structural theory, which emphasizes the impact of institutional features on job satisfaction; positive extrinsic environment by self-determination theory, which asserts that a positive extrinsic environment promotes competency and effective outcomes at work; and psychological theory, which emphasizes the proposed relationship between job performance and satisfaction. In addition to the measures for human capital theory, institutional variables (from structural theory and self-determination theory), and productivity measures (from psychological theory), the authors also selected sets of variables for personal characteristics to investigate their effects on job satisfaction. The results indicated that variables related to human capital theory, especially salary, contributed the most to job satisfaction, followed by those related to institutional variables. Personal variables and productivity variables as a whole contributed as well. The only other variable with marginal significance was faculty's perception of institutional support for teaching. Published by Elsevier Inc.

  14. A Game Theoretic Approach to Cyber Attack Prediction

    Peng Liu

    2005-11-28

    The area investigated by this project is cyber attack prediction. With a focus on correlation-based prediction, current attack prediction methodologies overlook the strategic nature of cyber attack-defense scenarios. As a result, current cyber attack prediction methodologies are very limited in predicting strategic behaviors of attackers in enforcing nontrivial cyber attacks such as DDoS attacks, and may result in low accuracy in correlation-based predictions. This project develops a game theoretic framework for cyber attack prediction, where an automatic game-theory-based attack prediction method is proposed. Being able to quantitatively predict the likelihood of (sequences of) attack actions, our attack prediction methodology can predict fine-grained strategic behaviors of attackers and may greatly improve the accuracy of correlation-based prediction. To our best knowledge, this project develops the first comprehensive framework for incentive-based modeling and inference of attack intent, objectives, and strategies; and this project develops the first method that can predict fine-grained strategic behaviors of attackers. The significance of this research and the benefit to the public can be demonstrated to certain extent by (a) the severe threat of cyber attacks to the critical infrastructures of the nation, including many infrastructures overseen by the Department of Energy, (b) the importance of cyber security to critical infrastructure protection, and (c) the importance of cyber attack prediction to achieving cyber security.

  15. A NETWORK-THEORETICAL APPROACH TO UNDERSTANDING INTERSTELLAR CHEMISTRY

    Jolley, Craig C.; Douglas, Trevor

    2010-01-01

    Recent years have seen dramatic advances in computational models of chemical processes in the interstellar medium (ISM). Typically, these models have been used to calculate changes in chemical abundances with time; the calculated abundances can then be compared with chemical abundances derived from observations. In this study, the output from an astrochemical simulation has been used to generate directed graphs with weighted edges; these have been analyzed with the tools of network theory to uncover whole-network properties of reaction systems in dark molecular clouds. The results allow the development of a model in which global network properties can be rationalized in terms of the basic physical properties of the reaction system. The ISM network exhibits an exponential degree distribution, which is likely to be a generic feature of chemical networks involving a broad range of reaction rate constants. While species abundances span several orders of magnitude, the formation and destruction rates for most species are approximately balanced-departures from this rule indicate species (such as CO) that play a critical role in shaping the dynamics of the system. Future theoretical or observational studies focusing on individual molecular species will be able to situate them in terms of their role in the complete system or quantify the degree to which they deviate from the typical system behavior.

  16. Conflicts about nuclear power safety: a decision theoretic approach

    Winterfeldt, D.V.; Rios, M.

    1980-01-01

    A series of psychological studies indicate that people's judgements of risks from energy production in general and nuclear power plants in particular deviate from technical and statistical estimates because social and psychological variables influence people's risk perception. After reviewing these studies a decision analytic methodology is outlined which incorporates such social and psychological variables in a formal analysis of the risks and benefits of nuclear energy production. The methodology is intended to identify groups with differing risk-benefit perceptions and to elicit and quantify their values and concerns. Such group and value structures are presented for the problem of choosing between a nuclear plant, a coal plant, and a conservation strategy

  17. The Empirical Measurement of a Theoretical Concept: Tracing Social Exclusion among Racial Minority and Migrant Groups in Canada

    Luann Good Gingrich

    2015-07-01

    Full Text Available This paper provides an in-depth description and case application of a conceptual model of social exclusion: aiming to advance existing knowledge on how to conceive of and identify this complex idea, evaluate the methodologies used to measure it, and reconsider what is understood about its social realities toward a meaningful and measurable conception of social inclusion. Drawing on Pierre Bourdieu’s conceptual tools of social fields and systems of capital, our research posits and applies a theoretical framework that permits the measurement of social exclusion as dynamic, social, relational, and material. We begin with a brief review of existing social exclusion research literature, and specifically examine the difficulties and benefits inherent in quantitatively operationalizing a necessarily multifarious theoretical concept. We then introduce our conceptual model of social exclusion and inclusion, which is built on measurable constructs. Using our ongoing program of research as a case study, we briefly present our approach to the quantitative operationalization of social exclusion using secondary data analysis in the Canadian context. Through the development of an Economic Exclusion Index, we demonstrate how our statistical and theoretical analyses evidence intersecting processes of social exclusion which produce consequential gaps and uneven trajectories for migrant individuals and groups compared with Canadian-born, and racial minority groups versus white individuals. To conclude, we consider some methodological implications to advance the empirical measurement of social inclusion.

  18. Cooperation, norms, and revolutions: a unified game-theoretical approach.

    Dirk Helbing

    Full Text Available BACKGROUND: Cooperation is of utmost importance to society as a whole, but is often challenged by individual self-interests. While game theory has studied this problem extensively, there is little work on interactions within and across groups with different preferences or beliefs. Yet, people from different social or cultural backgrounds often meet and interact. This can yield conflict, since behavior that is considered cooperative by one population might be perceived as non-cooperative from the viewpoint of another. METHODOLOGY AND PRINCIPAL FINDINGS: To understand the dynamics and outcome of the competitive interactions within and between groups, we study game-dynamical replicator equations for multiple populations with incompatible interests and different power (be this due to different population sizes, material resources, social capital, or other factors. These equations allow us to address various important questions: For example, can cooperation in the prisoner's dilemma be promoted, when two interacting groups have different preferences? Under what conditions can costly punishment, or other mechanisms, foster the evolution of norms? When does cooperation fail, leading to antagonistic behavior, conflict, or even revolutions? And what incentives are needed to reach peaceful agreements between groups with conflicting interests? CONCLUSIONS AND SIGNIFICANCE: Our detailed quantitative analysis reveals a large variety of interesting results, which are relevant for society, law and economics, and have implications for the evolution of language and culture as well.

  19. Success Determination by Innovation: A Theoretical Approach in Marketing

    Raj Kumar Gautam

    2012-01-01

    The paper aims at to identify the main issues in the marketing which needs immediate attention of the marketers. The importance of innovation in the marketing has also been highlighted and marketing mix have been related to innovative and creative ideas. The study is based on the secondary data, various research papers, articles has been studied to develop a innovative approach in the marketing. Marketing innovative ideas relating to business lead generation, product, price, distribution, pro...

  20. Mapping between Classical Risk Management and Game Theoretical Approaches

    Rajbhandari , Lisa; Snekkenes , Einar ,

    2011-01-01

    Part 2: Work in Progress; International audience; In a typical classical risk assessment approach, the probabilities are usually guessed and not much guidance is provided on how to get the probabilities right. When coming up with probabilities, people are generally not well calibrated. History may not always be a very good teacher. Hence, in this paper, we explain how game theory can be integrated into classical risk management. Game theory puts emphasis on collecting representative data on h...

  1. Theoretical approach of the seismic behaviour of a LMFBR core

    Parent, J.M.

    1983-01-01

    The vibratory behaviour of two one-degree-freedom mechanical systems, having known coupling and damping features, is investigated by transposition to two electrical circuits inductively coupled. This approach is carried out in two steps: the first one supposes that both circuits are identical, while the second one considers the general case where both circuits are unlike. It is shown that one or two resonant frequencies may occur, depending on the coupling and the damping conditions

  2. A measure theoretic approach to traffic flow optimization on networks

    Cacace, Simone; Camilli, Fabio; De Maio, Raul; Tosin, Andrea

    2018-01-01

    We consider a class of optimal control problems for measure-valued nonlinear transport equations describing traffic flow problems on networks. The objective isto minimise/maximise macroscopic quantities, such as traffic volume or average speed,controlling few agents, for example smart traffic lights and automated cars. The measuretheoretic approach allows to study in a same setting local and nonlocal drivers interactionsand to consider the control variables as additional measures interacting ...

  3. Theoretical approach of complex DNA lesions: from formation to repair

    Bignon, Emmanuelle

    2017-01-01

    This thesis work is focused on the theoretical modelling of DNA damages, from formation to repair. Several projects have been led in this framework, which can be sorted into three different parts. One on hand, we studied complex DNA reactivity. It included a study about 8-oxo-7,8-dihydro-guanine (8oxoG) mechanisms of formation, a project concerning the UV-induced pyrimidine 6-4 pyrimidone (6-4PP) endogenous photo-sensitizer features, and another one about DNA photo-sensitization by nonsteroidal anti-inflammatory drugs (i.e. ketoprofen and ibuprofen). On the other hand, we investigated mechanical properties of damaged DNA. The structural signature of a DNA lesion is of major importance for their repair, unfortunately only few NMR and X-ray structures of such systems are available. In order to gain insights into their dynamical structure, we investigated a series of complex damages: clustered abasic sites, interstrand cross-links, and the 6-4PP photo-lesion. Likewise, we studied the interaction modes DNA with several polyamines, which are well known to interact with the double helix, but also with the perspective to model DNA-protein cross-linking. The third part concerned the study of DNA interactions with repair enzymes. In line with the structural study about clustered abasic sites, we investigated the dynamics of the same system, but this time interacting with the APE1 endonuclease. We also studied interactions between the Fpg glycosylase with an oligonucleotides containing tandem 8-oxoG on one hand and 8-oxoG - abasic site as multiply damaged sites. Thus, we shed new lights on damaged DNA reactivity, structure and repair, which provides perspectives for biomedicine and life's mechanisms understanding as we begin to describe nucleosomal DNA. (author)

  4. A representation theoretic approach to the WZW Verlinde formula

    Fuchs, J

    1997-01-01

    By exploring the description of chiral blocks in terms of co-invariants, a proof of the Verlinde formula for WZW models is obtained which is entirely based on the representation theory of affine Lie algebras. In contrast to other proofs of the Verlinde formula, this approach works for all untwisted affine Lie algebras. As a by-product we obtain a homological interpretation of the Verlinde multiplicities, as Euler characteristics of complexes built from invariant tensors of finite-dimensional simple Lie algebras.

  5. Theoretical approach to the magnetocaloric effect with hysteresis

    Basso, V.; Bertotti, G.; LoBue, M.; Sasso, C.P.

    2005-01-01

    In this paper a thermodynamic model with internal variables is presented and applied to ferromagnetic hysteresis. The out-of-equilibrium Gibbs free energy of a magnetic system is expressed as a function of the internal state of the Preisach model. Expressions for the system entropy and the entropy production are derived. By this approach it is possible to reproduce the characteristic features of the experimentally observed temperature changes (of the order of 10 -4 K around room temperature) induced by the magnetic field along the hysteresis loop performed in iron under adiabatic condition

  6. Decision-theoretic approaches to non-knowledge in economics

    Svetlova, Ekaterina; van Elst, Henk

    2014-01-01

    We review two strands of conceptual approaches to the formal representation of a decision maker's non-knowledge at the initial stage of a static one-person, one-shot decision problem in economic theory. One focuses on representations of non-knowledge in terms of probability measures over sets of mutually exclusive and exhaustive consequence-relevant states of Nature, the other deals with unawareness of potentially important events by means of sets of states that are less complete than the ful...

  7. Participatory approaches for environmental governance: theoretical justifications and practical effects

    Van den Hove, Sybille

    2003-01-01

    A key justification for the rapid development of participatory approaches for environment and sustainable development governance stems from the characteristics of environmental issues. Environmental issues - and radioactive waste disposal is a good example - typically present four important physical characteristics: complexity, uncertainty, large temporal and spatial scales, and irreversibility, which all have consequences on what can be called the social characteristics of environmental issues. These include: social complexity and conflicts of interests, transversality, diffuse responsibilities and impacts, no clear division between micro- and macro-levels, and short-term costs of dealing with the issue associated with benefits which might occur only in the long-term. In turn, these physical and social characteristics determine the type of problem-solving processes needed to tackle environmental issues. It appears that the problem-solving processes best suited to confront global environmental issues will be dynamic processes of capacity-building, - aiming at innovative, flexible and adjustable answers, - allowing for the progressive integration of information as it becomes available, and of different value judgements and logics, - involving various actors from different backgrounds and levels. In promoting more democratic practices, these processes additionally should supersede traditional politics and allow co-ordination across different policy areas. It is deemed that participatory approaches have the potential to meet these problem-solving requirements

  8. NON-TERRITORIAL AUTONOMY IN RUSSIA: PRACTICAL IMPLICATIONS OF THEORETICAL APPROACHES

    Tatiana RUDNEVA

    2012-06-01

    Full Text Available Despite the theoretical possibility to use non-territorial autonomy as a mechanism through which ethnic groups can fulfil their right to selfdetermination along with other minority rights, not many states have been willing to put theory into practice. The article offers an explanation why wider applicability of NTA is problematic by arguing that the theory itself is not yet polished enough to be implemented. The study includes examination of both theoretical approaches and empirical data from a case study of an attempt to establish NTAs in the Russian Federation. The findings suggest that inconsistencies and unclarities in the theory do correlate with practical flaws of NTAs, which allows to suggest that when the theory is tested empirically, the reality reveals all the flaws of the theory. The results indicate that the concept of NTA needs further refinement and development to make it more practice-oriented and applicable. As the problem of minority rights is still to be dealt with, we also propose a model of global union of NTAs where each ethnic group is represented by a non-governmental organisation, which seems to be more applicable than the others, alongside a number of other mechanisms that are even more essential and universal and focus on defending basic human rights

  9. Theoretical triangulation as an approach for revealing the complexity of a classroom discussion

    van Drie, J.; Dekker, R.

    2013-01-01

    In this paper we explore the value of theoretical triangulation as a methodological approach for the analysis of classroom interaction. We analyze an excerpt of a whole-class discussion in history from three theoretical perspectives: interactivity of the discourse, conceptual level raising and

  10. Consumer Perception of Competitiveness – Theoretical-Instrumental Approach

    Duralia Oana

    2016-04-01

    Full Text Available Behaviorist economic approach has recorded a quantum leap in a relatively short period of time, as studying the relationship between consumer behavior and companies’ strategic decisions based on market competitiveness are no longer an unknown area. However, this issue remains actual in view of the fact that during the decision process of purchase, consumers do not always behave rationally, as they are the only ones who can appreciate if the offer of the company, in terms of range, quality, price and auxiliary services meet their needs or not. In this context, this paper aims to deepen the existing interconnection between the market decisions of the enterprise and consumer behavior, as measure standard for the competitiveness of a firm on a certain market.

  11. Theoretical and empirical approaches to using films as a means to increase communication efficiency.

    Kiselnikova, N.V.

    2016-07-01

    Full Text Available The theoretical framework of this analytic study is based on studies in the field of film perception. Films are considered as a communicative system that is encrypted in an ordered series of shots, and decoding proceeds during perception. The shots are the elements of a cinematic message that must be “read” by viewer. The objective of this work is to analyze the existing theoretical approaches to using films in psychotherapy and education. An original approach to film therapy that is based on teaching clients to use new communicative sets and psychotherapeutic patterns through watching films is presented. The article specifies the main emphasized points in theories of film therapy and education. It considers the specifics of film therapy in the process of increasing the effectiveness of communication. It discusses the advantages and limitations of the proposed method. The contemporary forms of film therapy and the formats of cinema clubs are criticized. The theoretical assumptions and empirical research that could be used as a basis for a method of developing effective communication by means of films are discussed. Our studies demonstrate that the usage of film therapy must include an educational stage for more effective and stable results. This means teaching viewers how to recognize certain psychotherapeutic and communicative patterns in the material of films, to practice the skill of finding as many examples as possible for each pattern and to transfer the acquired schemes of analyzing and recognizing patterns into one’s own life circumstances. The four stages of the film therapeutic process as well as the effects that are achieved at each stage are described in detail. In conclusion, the conditions under which the usage of the film therapy method would be the most effective are observed. Various properties of client groups and psychotherapeutic scenarios for using the method of active film therapy are described.

  12. [Systemic inflammation: theoretical and methodological approaches to description of general pathological process model. Part 3. Backgroung for nonsyndromic approach].

    Gusev, E Yu; Chereshnev, V A

    2013-01-01

    Theoretical and methodological approaches to description of systemic inflammation as general pathological process are discussed. It is shown, that there is a need of integration of wide range of types of researches to develop a model of systemic inflammation.

  13. Field-theoretic approach to gravity in the flat space-time

    Cavalleri, G [Centro Informazioni Studi Esperienze, Milan (Italy); Milan Univ. (Italy). Ist. di Fisica); Spinelli, G [Istituto di Matematica del Politecnico di Milano, Milano (Italy)

    1980-01-01

    In this paper it is discussed how the field-theoretical approach to gravity starting from the flat space-time is wider than the Einstein approach. The flat approach is able to predict the structure of the observable space as a consequence of the behaviour of the particle proper masses. The field equations are formally equal to Einstein's equations without the cosmological term.

  14. Sharing solutions - The users' group approach

    Kania, G.; Winter, K.

    1991-01-01

    Regulatory compliance, operating efficiency, and plant-life extension are common goals shared by all nuclear power plants. To achieve these goals, nuclear utilities must be proactive and responsive to the regulatory agencies, work together with each other in the sharing of operating experiences and solution to problems, and develop long-term working relationships with an even smaller number of quality suppliers. Users' and owners' groups are one of the most effective means of accomplishing these objectives. Users' groups facilitate communication between nuclear power plants and provide an interactive vendor interface. Both the utilities and suppliers benefit through shared information and improved customer feedback. This paper describes the evolution and experiences of the Sorrento Electronics (SE) Radiation Monitoring System (RMS) Users' Group. The authors highlight the group's past successes and plans for the future

  15. New renormalization group approach to multiscale problems

    Einhorn, M B; Jones, D R.T.

    1984-02-27

    A new renormalization group is presented which exploits invariance with respect to more than one scale. The method is illustrated by a simple model, and future applications to fields such as critical phenomena and supersymmetry are speculated upon.

  16. A measure theoretical approach to quantum stochastic processes

    Waldenfels, Wilhelm von

    2014-04-01

    Authored by a leading researcher in the field. Self-contained presentation of the subject matter. Examines a number of worked examples in detail. This monograph takes as starting point that abstract quantum stochastic processes can be understood as a quantum field theory in one space and in one time coordinate. As a result it is appropriate to represent operators as power series of creation and annihilation operators in normal-ordered form, which can be achieved using classical measure theory. Considering in detail four basic examples (e.g. a two-level atom coupled to a heat bath of oscillators), in each case the Hamiltonian of the associated one-parameter strongly continuous group is determined and the spectral decomposition is explicitly calculated in the form of generalized eigen-vectors. Advanced topics include the theory of the Hudson-Parthasarathy equation and the amplified oscillator problem. To that end, a chapter on white noise calculus has also been included.

  17. Space and Time as Relations: The Theoretical Approach of Leibniz

    Basil Evangelidis

    2018-04-01

    Full Text Available The epistemological rupture of Copernicus, the laws of planetary motions of Kepler, the comprehensive physical observations of Galileo and Huygens, the conception of relativity, and the physical theory of Newton were components of an extremely fertile and influential cognitive environment that prompted the restless Leibniz to shape an innovative theory of space and time. This theory expressed some of the concerns and intuitions of the scientific community of the seventeenth century, in particular the scientific group of the Academy of Sciences of Paris, but remained relatively unknown until the twentieth century. After Einstein, however, the relational theory of Leibniz gained wider respect and fame. The aim of this article is to explain how Leibniz foresaw relativity, through his critique of contemporary mechanistic philosophy.

  18. THE FORMS OF UNCONVENTIONAL ADVERTISING – A THEORETICAL APPROACH

    Maria Alina JURCA

    2010-01-01

    Full Text Available The large number of advertisements that the consumers are bombarded with every day has made them virtually immune to commercial messages. This is why advertisers are trying to find new, alternative ways to reach the customers, which are comprised by economic literature in the concept of unconventional advertising. Based on a thorough documentary research, this study identifies the existing forms of unconventional advertising by presenting them in the order of their frequency of use and it tries to group the ones with similar characteristics into somewhat larger categories. A better understanding and knowledge of these new forms of advertising can provide marketing and advertising specialists with new strategies to convey the brand message that can grab the attention of any prospect customer.

  19. A Theoretical Approach to Information Needs Across Different Healthcare Stakeholders

    Raitoharju, Reetta; Aarnio, Eeva

    Increased access to medical information can lead to information overload among both the employees in the healthcare sector as well as among healthcare consumers. Moreover, medical information can be hard to understand for consumers who have no prerequisites for interpreting and understanding it. Information systems (e.g. electronic patient records) are normally designed to meet the demands of one professional group, for instance those of physicians. Therefore, the same information in the same form is presented to all the users of the systems regardless of the actual need or prerequisites. The purpose of this article is to illustrate the differences in information needs across different stakeholders in healthcare. A literature review was conducted to collect examples of these different information needs. Based on the findings the role of more user specific information systems is discussed.

  20. A measure theoretical approach to quantum stochastic processes

    Von Waldenfels, Wilhelm

    2014-01-01

    This monograph takes as starting point that abstract quantum stochastic processes can be understood as a quantum field theory in one space and in one time coordinate. As a result it is appropriate to represent operators as power series of creation and annihilation operators in normal-ordered form, which can be achieved using classical measure theory. Considering in detail four basic examples (e.g. a two-level atom coupled to a heat bath of oscillators), in each case the Hamiltonian of the associated one-parameter strongly continuous group is determined and the spectral decomposition is explicitly calculated in the form of generalized eigen-vectors. Advanced topics include the theory of the Hudson-Parthasarathy equation and the amplified oscillator problem. To that end, a chapter on white noise calculus has also been included.

  1. Group Counseling Optimization: A Novel Approach

    Eita, M. A.; Fahmy, M. M.

    A new population-based search algorithm, which we call Group Counseling Optimizer (GCO), is presented. It mimics the group counseling behavior of humans in solving their problems. The algorithm is tested using seven known benchmark functions: Sphere, Rosenbrock, Griewank, Rastrigin, Ackley, Weierstrass, and Schwefel functions. A comparison is made with the recently published comprehensive learning particle swarm optimizer (CLPSO). The results demonstrate the efficiency and robustness of the proposed algorithm.

  2. A Game Theoretic Approach to Nuclear Security Analysis against Insider Threat

    Kim, Kyonam; Kim, So Young; Yim, Mansung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Schneider, Erich [Univ. of Texas at Austin, Texas (United States)

    2014-05-15

    As individuals with authorized access to a facility and system who use their trusted position for unauthorized purposes, insiders are able to take advantage of their access rights and knowledge of a facility to bypass dedicated security measures. They can also capitalize on their knowledge to exploit any vulnerabilities in safety-related systems, with cyber security of safety-critical information technology systems offering an important example of the 3S interface. While this Probabilistic Risk Assessment (PRA) approach is appropriate for describing fundamentally random events like component failure of a safety system, it does not capture the adversary's intentions, nor does it account for adversarial response and adaptation to defensive investments. To address these issues of intentionality and interactions, this study adopts a game theoretic approach. The interaction between defender and adversary is modeled as a two-person Stackelberg game. The optimal strategy of both players is found from the equilibrium of this game. A defender strategy consists of a set of design modifications and/or post-construction security upgrades. An attacker strategy involves selection of a target as well as a pathway to that target. In this study, application of the game theoretic approach is demonstrated using a simplified test case problem. Novel to our approach is the modeling of insider threat that affects the non-detection probability of an adversary. The game-theoretic approach has the advantage of modelling an intelligent adversary who has an intention and complete knowledge of the facility. In this study, we analyzed the expected adversarial path and security upgrades with a limited budget with insider threat modeled as increasing the non-detection probability. Our test case problem categorized three groups of adversary paths assisted by insiders and derived the largest insider threat in terms of the budget for security upgrades. Certainly more work needs to be done to

  3. A Game Theoretic Approach to Nuclear Security Analysis against Insider Threat

    Kim, Kyonam; Kim, So Young; Yim, Mansung; Schneider, Erich

    2014-01-01

    As individuals with authorized access to a facility and system who use their trusted position for unauthorized purposes, insiders are able to take advantage of their access rights and knowledge of a facility to bypass dedicated security measures. They can also capitalize on their knowledge to exploit any vulnerabilities in safety-related systems, with cyber security of safety-critical information technology systems offering an important example of the 3S interface. While this Probabilistic Risk Assessment (PRA) approach is appropriate for describing fundamentally random events like component failure of a safety system, it does not capture the adversary's intentions, nor does it account for adversarial response and adaptation to defensive investments. To address these issues of intentionality and interactions, this study adopts a game theoretic approach. The interaction between defender and adversary is modeled as a two-person Stackelberg game. The optimal strategy of both players is found from the equilibrium of this game. A defender strategy consists of a set of design modifications and/or post-construction security upgrades. An attacker strategy involves selection of a target as well as a pathway to that target. In this study, application of the game theoretic approach is demonstrated using a simplified test case problem. Novel to our approach is the modeling of insider threat that affects the non-detection probability of an adversary. The game-theoretic approach has the advantage of modelling an intelligent adversary who has an intention and complete knowledge of the facility. In this study, we analyzed the expected adversarial path and security upgrades with a limited budget with insider threat modeled as increasing the non-detection probability. Our test case problem categorized three groups of adversary paths assisted by insiders and derived the largest insider threat in terms of the budget for security upgrades. Certainly more work needs to be done to

  4. Theoretical approaches to x-ray absorption fine structure

    Rehr, J. J.; Albers, R. C.

    2000-01-01

    Dramatic advances in the understanding of x-ray absorption fine structure (XAFS) have been made over the past few decades, which have led ultimately to a highly quantitative theory. This review covers these developments from a unified multiple-scattering viewpoint. The authors focus on extended x-ray absorption fine structure (EXAFS) well above an x-ray edge, and, to a lesser extent, on x-ray absorption near-edge structure (XANES) closer to an edge. The discussion includes both formal considerations, derived from a many-electron formulation, and practical computational methods based on independent-electron models, with many-body effects lumped into various inelastic losses and energy shifts. The main conceptual issues in XAFS theory are identified and their relative importance is assessed; these include the convergence of the multiple-scattering expansion, curved-wave effects, the scattering potential, inelastic losses, self-energy shifts, and vibrations and structural disorder. The advantages and limitations of current computational approaches are addressed, with particular regard to quantitative experimental comparisons. (c) 2000 The American Physical Society

  5. Hybrid empirical--theoretical approach to modeling uranium adsorption

    Hull, Larry C.; Grossman, Christopher; Fjeld, Robert A.; Coates, John T.; Elzerman, Alan W.

    2004-01-01

    An estimated 330 metric tons of U are buried in the radioactive waste Subsurface Disposal Area (SDA) at the Idaho National Engineering and Environmental Laboratory (INEEL). An assessment of U transport parameters is being performed to decrease the uncertainty in risk and dose predictions derived from computer simulations of U fate and transport to the underlying Snake River Plain Aquifer. Uranium adsorption isotherms were measured for 14 sediment samples collected from sedimentary interbeds underlying the SDA. The adsorption data were fit with a Freundlich isotherm. The Freundlich n parameter is statistically identical for all 14 sediment samples and the Freundlich K f parameter is correlated to sediment surface area (r 2 =0.80). These findings suggest an efficient approach to material characterization and implementation of a spatially variable reactive transport model that requires only the measurement of sediment surface area. To expand the potential applicability of the measured isotherms, a model is derived from the empirical observations by incorporating concepts from surface complexation theory to account for the effects of solution chemistry. The resulting model is then used to predict the range of adsorption conditions to be expected in the vadose zone at the SDA based on the range in measured pore water chemistry. Adsorption in the deep vadose zone is predicted to be stronger than in near-surface sediments because the total dissolved carbonate decreases with depth

  6. An Information-Theoretic Approach to PMU Placement in Electric Power Systems

    Li, Qiao; Cui, Tao; Weng, Yang; Negi, Rohit; Franchetti, Franz; Ilic, Marija D.

    2012-01-01

    This paper presents an information-theoretic approach to address the phasor measurement unit (PMU) placement problem in electric power systems. Different from the conventional 'topological observability' based approaches, this paper advocates a much more refined, information-theoretic criterion, namely the mutual information (MI) between the PMU measurements and the power system states. The proposed MI criterion can not only include the full system observability as a special case, but also ca...

  7. Thermochemical study of cyanopyrazines: Experimental and theoretical approaches

    Miranda, Margarida S.; Morais, Victor M.F.; Matos, M. Agostinha R.

    2006-01-01

    The standard (p - bar =0.1MPa) molar energy of combustion, at T=298.15K, of crystalline 2,3-dicyanopyrazine was measured by static bomb calorimetry, in oxygen atmosphere. The standard molar enthalpy of sublimation, at T=298.15K, was obtained by Calvet Microcalorimetry, allowing the calculation of the standard molar enthalpy of formation of the compound, in the gas phase, at T=298.15K: Δ f H m - bar (g)=(518.7+/-3.4)kJ.mol -1 . In addition, the geometries of all cyanopyrazines were obtained using density functional theory with the B3LYP functional and two basis sets: 6-31G* and 6-311G**. These calculations were then used for a better understanding of the relation between structure and energetics of the cyanopyrazine systems. These calculations also reproduce measured standard molar enthalpies of formation with some accuracy and do provide estimates of this thermochemical parameter for those compounds that could not be studied experimentally, namely the tri- and tetracyanopyrazines: the strong electron withdrawing cyano group on the pyrazine ring makes cyanopyrazines highly destabilized compounds

  8. Group Counseling Using the Gestalt Approach.

    Schneibel, Dan

    The phenomenological-existential therapy known as gestalt therapy sees awareness as its major goal. Clients are helped to become aware of what they are doing, how they are doing it, and how they can change themselves while, at the same time, learning to accept and value themselves. An important topic in the gestalt group process is the key…

  9. Group-theoretical method in the many-beam theory of electron diffraction

    Kogiso, Motokazu; Takahashi, Hidewo.

    1977-01-01

    A group-theoretical method is developed for the many-beam dynamical theory of the symmetric Laue case. When the incident wave is directed so that the Laue point lies on a symmetric position in the reciprocal lattice, the dispersion matrix in the fundamental equation can be reduced to a block diagonal form. The transformation matrix is composed of column vectors belonging to irreducible representations of the group of the incident wave vector. Without performing reduction, the reduced form of the dispersion matrix is determined from characters of representations. Practical application is made to the case of symmorphic crystals, where general reduced forms and all solvable examples are given in terms of some geometrical factors of reciprocal lattice arrangements. (auth.)

  10. The group manifold approach to unified gravity

    Regge, T.

    1984-01-01

    These lectures start with a synopsis of historical results in the construction of unified theories of gravity. The author keeps some mathematical rigour throughout the lectures. He gives a provisional description of supermanifolds and a set of formal rules intended to manipulate superforms or supermanifolds. Super Lie groups are discussed as well as the dimensional reduction of gravity theories, the Kaluza-Klein theory. A formal introduction of supersymmetry is given. (Auth.)

  11. Generalized Hubbard Hamiltonian: renormalization group approach

    Cannas, S.A.; Tamarit, F.A.; Tsallis, C.

    1991-01-01

    We study a generalized Hubbard Hamiltonian which is closed within the framework of a Quantum Real Space Renormalization Group, which replaces the d-dimensional hypercubic lattice by a diamond-like lattice. The phase diagram of the generalized Hubbard Hamiltonian is analyzed for the half-filled band case in d = 2 and d = 3. Some evidence for superconductivity is presented. (author). 44 refs., 12 figs., 2 tabs

  12. Chaotic renormalization group approach to disordered systems

    Oliveira, P.M.C. de; Continentino, M.A.; Makler, S.S.; Anda, E.V.

    1984-01-01

    We study the eletronic properties of the disordered linear chain using a technique previously developed by some of the authors for an ordered chain. The equations of motion for the one electron Green function are obtained and the configuration average is done according to the GK scheme. The dynamical problem is transformed, using a renormalization group procedure, into a bidimensional map. The properties of this map are investigated and related to the localization properties of the eletronic system. (Author) [pt

  13. Distraction sneakers decrease the expected level of aggression within groups: a game-theoretic model.

    Dubois, Frédérique; Giraldeau, Luc-Alain; Hamilton, Ian M; Grant, James W A; Lefebvre, Louis

    2004-08-01

    Hawk-dove games have been extensively used to predict the conditions under which group-living animals should defend their resources against potential usurpers. Typically, game-theoretic models on aggression consider that resource defense may entail energetic and injury costs. However, intruders may also take advantage of owners who are busy fighting to sneak access to unguarded resources, imposing thereby an additional cost on the use of the escalated hawk strategy. In this article we modify the two-strategy hawk-dove game into a three-strategy hawk-dove-sneaker game that incorporates a distraction-sneaking tactic, allowing us to explore its consequences on the expected level of aggression within groups. Our model predicts a lower proportion of hawks and hence lower frequencies of aggressive interactions within groups than do previous two-strategy hawk-dove games. The extent to which distraction sneakers decrease the frequency of aggression within groups, however, depends on whether they search only for opportunities to join resources uncovered by other group members or for both unchallenged resources and opportunities to usurp.

  14. The Formation of Instruments of Management of Industrial Enterprises According to the Theoretical and Functional Approaches

    Raiko Diana V.

    2018-03-01

    Full Text Available The article is aimed at the substantiation based on the analysis of the company theories of the basic theoretical provisions on the formation of industrial enterprise management instruments. The article determines that the subject of research in theories is enterprise, the object is the process of management of potential according to the forms of business organization and technology of partnership relations, the goal is high financial results, stabilization of the activity, and social responsibility. The publication carries out an analysis of enterprise theories on the determining of its essence as a socio-economic system in the following directions: technical preparation of production, economic theory and law, theory of systems, marketing-management. As a result of the research, the general set of functions has been identified – the socio-economic functions of enterprise by groups: information-legal, production, marketing-management, social responsibility. When building management instruments, it is suggested to take into consideration the direct and inverse relationships of enterprise at all levels of management – micro, meso and macro. On this ground, the authors have developed provisions on formation of instruments of management of industrial enterprises according to two approachestheoretical and functional.

  15. Bootstrap percolation: a renormalisation group approach

    Branco, N.S.; Santos, Raimundo R. dos; Queiroz, S.L.A. de.

    1984-02-01

    In bootstrap percolation, sites are occupied at random with probability p, but each site is considered active only if at least m of its neighbours are also active. Within an approximate position-space renormalization group framework on a square lattice we obtain the behaviour of the critical concentration p (sub)c and of the critical exponents ν and β for m = 0 (ordinary percolation), 1,2 and 3. We find that the bootstrap percolation problem can be cast into different universality classes, characterized by the values of m. (author) [pt

  16. Model-free information-theoretic approach to infer leadership in pairs of zebrafish.

    Butail, Sachit; Mwaffo, Violet; Porfiri, Maurizio

    2016-04-01

    Collective behavior affords several advantages to fish in avoiding predators, foraging, mating, and swimming. Although fish schools have been traditionally considered egalitarian superorganisms, a number of empirical observations suggest the emergence of leadership in gregarious groups. Detecting and classifying leader-follower relationships is central to elucidate the behavioral and physiological causes of leadership and understand its consequences. Here, we demonstrate an information-theoretic approach to infer leadership from positional data of fish swimming. In this framework, we measure social interactions between fish pairs through the mathematical construct of transfer entropy, which quantifies the predictive power of a time series to anticipate another, possibly coupled, time series. We focus on the zebrafish model organism, which is rapidly emerging as a species of choice in preclinical research for its genetic similarity to humans and reduced neurobiological complexity with respect to mammals. To overcome experimental confounds and generate test data sets on which we can thoroughly assess our approach, we adapt and calibrate a data-driven stochastic model of zebrafish motion for the simulation of a coupled dynamical system of zebrafish pairs. In this synthetic data set, the extent and direction of the coupling between the fish are systematically varied across a wide parameter range to demonstrate the accuracy and reliability of transfer entropy in inferring leadership. Our approach is expected to aid in the analysis of collective behavior, providing a data-driven perspective to understand social interactions.

  17. Renormalization group approach to soft gluon resummation

    Forte, Stefano; Ridolfi, Giovanni

    2003-01-01

    We present a simple proof of the all-order exponentiation of soft logarithmic corrections to hard processes in perturbative QCD. Our argument is based on proving that all large logs in the soft limit can be expressed in terms of a single dimensionful variable, and then using the renormalization group to resum them. Beyond the next-to-leading log level, our result is somewhat less predictive than previous all-order resummation formulae, but it does not rely on non-standard factorization, and it is thus possibly more general. We use our result to settle issues of convergence of the resummed series, we discuss scheme dependence at the resummed level, and we provide explicit resummed expressions in various factorization schemes

  18. Theoretically informed correlates of hepatitis B knowledge among four Asian groups: the health behavior framework.

    Maxwell, Annette E; Stewart, Susan L; Glenn, Beth A; Wong, Weng Kee; Yasui, Yutaka; Chang, L Cindy; Taylor, Victoria M; Nguyen, Tung T; Chen, Moon S; Bastani, Roshan

    2012-01-01

    Few studies have examined theoretically informed constructs related to hepatitis B (HBV) testing, and comparisons across studies are challenging due to lack of uniformity in constructs assessed. The present analysis examined relationships among Health Behavior Framework factors across four Asian American groups to advance the development of theory-based interventions for HBV testing in at-risk populations. Data were collected from 2007-2010 as part of baseline surveys during four intervention trials promoting HBV testing among Vietnamese-, Hmong-, Korean- and Cambodian-Americans (n = 1,735). Health Behavior Framework constructs assessed included: awareness of HBV, knowledge of transmission routes, perceived susceptibility, perceived severity, doctor recommendation, stigma of HBV infection, and perceived efficacy of testing. Within each group we assessed associations between our intermediate outcome of knowledge of HBV transmission and other constructs, to assess the concurrent validity of our model and instruments. While the absolute levels for Health Behavior Framework factors varied across groups, relationships between knowledge and other factors were generally consistent. This suggests similarities rather than differences with respect to posited drivers of HBV-related behavior. Our findings indicate that Health Behavior Framework constructs are applicable to diverse ethnic groups and provide preliminary evidence for the construct validity of the Health Behavior Framework.

  19. On the group theoretical meaning of conformal field theories in the framework of coadjoint orbits

    Aratyn, H.; Nissimov, E.; Pacheva, S.

    1990-01-01

    We present a unifying approach to conformal field theories and other geometric models within the formalism of coadjoint orbits of infinite dimensional Lie groups with central extensions. Starting from the previously obtained general formula for the symplectic action in terms of two fundamental group one-cocycles, we derive the most general form of the Polyakov-Wiegmann composition laws for any geometric model. These composition laws are succinct expressions of all pertinent Noether symmetries. As a basic consequence we obtain Ward identities allowing for the exact quantum solvability of any geometric model. (orig.)

  20. Data structure techniques for the graphical special unitary group approach to arbitrary spin representations

    Kent, R.D.; Schlesinger, M.

    1987-01-01

    For the purpose of computing matrix elements of quantum mechanical operators in complex N-particle systems it is necessary that as much of each irreducible representation be stored in high-speed memory as possible in order to achieve the highest possible rate of computations. A graph theoretic approach to the representation of N-particle systems involving arbitrary single-particle spin is presented. The method involves a generalization of a technique employed by Shavitt in developing the graphical group approach (GUGA) to electronic spin-orbitals. The methods implemented in GENDRT and DRTDIM overcome many deficiencies inherent in other approaches, particularly with respect to utilization of memory resources, computational efficiency in the recognition and evaluation of non-zero matrix elements of certain group theoretic operators and complete labelling of all the basis states of the permutation symmetry (S N ) adapted irreducible representations of SU(n) groups. (orig.)

  1. Improving the interpersonal competences of head nurses through Peplau's theoretical active learning approach.

    Suhariyanto; Hariyati, Rr Tutik Sri; Ungsianik, Titin

    2018-02-01

    Effective interpersonal skills are essential for head nurses in governing and managing their work units. Therefore, an active learning strategy could be the key to enhance the interpersonal competences of head nurses. This study aimed to investigate the effects of Peplau's theoretical approach of active learning on the improvement of head nurses' interpersonal skills. This study used a pre-experimental design with one group having pretests and posttests, without control group. A total sample of 25 head nurses from inpatient units of a wellknown private hospital in Jakarta was involved in the study. Data were analyzed using the paired t-test. The results showed a significant increase in head nurses' knowledge following the training to strengthen their interpersonal roles (P=.003). The results also revealed significant increases in the head nurses' skills in playing the roles of leader (P=.006), guardian (P=.014), and teacher/speaker (P=.015). Nonetheless, the results showed no significant increases in the head nurses' skills in playing the roles of counselor (P=.092) and stranger (P=.182). Training in strengthening the interpersonal roles of head nurses significantly increased the head nurses' knowledge and skills. The results of the study suggested the continuation of active learning strategies to improve the interpersonal abilities of head nurses. Furthermore, these strategies could be used to build the abilities of head nurses in other managerial fields. Copyright © 2018 Elsevier España, S.L.U. All rights reserved.

  2. Theoretical simulations on the antioxidant mechanism of naturally occurring flavonoid: A DFT approach

    Praveena, R.; Sadasivam, K.

    2016-01-01

    Synthetic antioxidants such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are found to be toxic, hence non-carcinogenic naturally occurring radical scavengers especially flavonoids have gained considerable importance in the past two decades. In the present investigation, the radical scavenging activity of C-glycosyl flavonoids is evaluated using theoretical approach which could broaden its scope in therapeutic applications. Gas and solvent phase studies of structural and molecular characteristics of C-glycosyl flavonoid, isovitexin is investigated through hydrogen atom transfer mechanism (HAT), Electron transfer-proton transfer (ET–PT) and Sequential proton loss electron transfer (SPLET) by Density functional theory (DFT) using hybrid parameters. The computed values of the adiabatic ionization potential, electron affinity, hardness, softness, electronegativity and electrophilic index indicate that isovitexin possess good radical scavenging activity. The behavior of different –OH groups in polyphenolic compounds is assessed by considering electronic effects of the neighbouring groups and the overall geometry of molecule which in turn helps in analyzing the antioxidant capacity of the polyphenolic molecule. The studies indicate that the H–atom abstraction from 4’–OH site is preferred during the radical scavenging process. From Mulliken spin density analysis and FMOs, B–ring is found to be more delocalized center and capable of electron donation. Comparison of antioxidant activity of vitexin and isovitexin leads to the conclusion that isovitexin acts as a better radical scavenger. This is an evidence for the importance of position of glucose unit in the flavonoid.

  3. Theoretical simulations on the antioxidant mechanism of naturally occurring flavonoid: A DFT approach

    Praveena, R. [Department of Chemistry, Bannari Amman Institute of Technology, Sathyamangalam, Erode, Tamil Nadu (India); Sadasivam, K. [Department of Physics, Bannari Amman Institute of Technology, Sathyamangalam, Erode, Tamil Nadu (India)

    2016-05-06

    Synthetic antioxidants such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are found to be toxic, hence non-carcinogenic naturally occurring radical scavengers especially flavonoids have gained considerable importance in the past two decades. In the present investigation, the radical scavenging activity of C-glycosyl flavonoids is evaluated using theoretical approach which could broaden its scope in therapeutic applications. Gas and solvent phase studies of structural and molecular characteristics of C-glycosyl flavonoid, isovitexin is investigated through hydrogen atom transfer mechanism (HAT), Electron transfer-proton transfer (ET–PT) and Sequential proton loss electron transfer (SPLET) by Density functional theory (DFT) using hybrid parameters. The computed values of the adiabatic ionization potential, electron affinity, hardness, softness, electronegativity and electrophilic index indicate that isovitexin possess good radical scavenging activity. The behavior of different –OH groups in polyphenolic compounds is assessed by considering electronic effects of the neighbouring groups and the overall geometry of molecule which in turn helps in analyzing the antioxidant capacity of the polyphenolic molecule. The studies indicate that the H–atom abstraction from 4’–OH site is preferred during the radical scavenging process. From Mulliken spin density analysis and FMOs, B–ring is found to be more delocalized center and capable of electron donation. Comparison of antioxidant activity of vitexin and isovitexin leads to the conclusion that isovitexin acts as a better radical scavenger. This is an evidence for the importance of position of glucose unit in the flavonoid.

  4. Nuclear energy policy analysis under uncertainties : applications of new utility theoretic approaches

    Ra, Ki Yong

    1992-02-01

    For the purpose of analyzing the nuclear energy policy under uncertainties, new utility theoretic approaches were applied. The main discoveries of new utility theories are that, firstly, the consequences can affect the perceived probabilities, secondly, the utilities are not fixed but can change, and finally, utilities and probabilities thus should be combined dependently to determine the overall worth of risky option. These conclusions were applied to develop the modified expected utility model and to establish the probabilistic nuclear safety criterion. The modified expected utility model was developed in order to resolve the inconsistencies between the expected utility model and the actual decision behaviors. Based on information theory and Bayesian inference, the modified probabilities were obtained as the stated probabilities times substitutional factors. The model theoretically predicts that the extreme value outcomes are perceived as to be more likely to occur than medium value outcomes. This prediction is consistent with the first finding of new utility theories that the consequences can after the perceived probabilities. And further with this theoretical prediction, the decision behavior of buying lottery ticket, of paying for insurance and of nuclear catastrophic risk aversion can well be explained. Through the numerical application, it is shown that the developed model can well explain the common consequence effect, common ratio effect and reflection effect. The probabilistic nuclear safety criterion for core melt frequency was established: Firstly, the distribution of the public's safety goal (DPSG) was proposed for representing the public's group preference under risk. Secondly, a new probabilistic safety criterion (PSC) was established, in which the DPSG was used as a benchmark for evaluating the results of probabilistic safety assessment. Thirdly, a log-normal distribution was proposed as the appropriate DPSG for core melt frequency using the

  5. New strings for old Veneziano amplitudes. II. Group-theoretic treatment

    Kholodenko, A. L.

    2006-09-01

    In this part of our four parts work we use theory of polynomial invariants of finite pseudo-reflection groups in order to reconstruct both the Veneziano and Veneziano-like (tachyon-free) amplitudes and the generating function reproducing these amplitudes. We demonstrate that such generating function and amplitudes associated with it can be recovered with help of finite dimensional exactly solvableN=2 supersymmetric quantum mechanical model known earlier from works of Witten, Stone and others. Using the Lefschetz isomorphism theorem we replace traditional supersymmetric calculations by the group-theoretic thus solving the Veneziano model exactly using standard methods of representation theory. Mathematical correctness of our arguments relies on important theorems by Shepard and Todd, Serre and Solomon proven respectively in the early 50s and 60s and documented in the monograph by Bourbaki. Based on these theorems, we explain why the developed formalism leaves all known results of conformal field theories unchanged. We also explain why these theorems impose stringent requirements connecting analytical properties of scattering amplitudes with symmetries of space-time in which such amplitudes act.

  6. Relationships between the group-theoretic and soliton-theoretic techniques for generating stationary axisymmetric gravitational solutions

    Cosgrove, C.M.

    1980-01-01

    We investigate the precise interrelationships between several recently developed solution-generating techniques capable of generating asymptotically flat gravitational solutions with arbitrary multipole parameters. The transformations we study in detail here are the Lie groups Q and Q of Cosgrove, the Hoenselaers--Kinnersley--Xanthopoulos (HKX) transformations and their SL(2) tensor generalizations, the Neugebauer--Kramer discrete mapping, the Neugebauer Baecklund transformations I 1 and I 2 , the Harrison Baecklund transformation, and the Belinsky--Zakharov (BZ) one- and two-soliton transformations. Two particular results, among many reported here, are that the BZ soliton transformations are essentially equivalent to Harrison transformations and that the generalized HKX transformation may be deduced as a confluent double soliton transformation. Explicit algebraic expressions are given for the transforms of the Kinnersley--Chitre generating functions under all of the above transformations. In less detail, we also study the Kinnersley--Chitre β transformations, the non-null HKX transformations, and the Hilbert problems proposed independently by Belinsky and Zakharov, and Hauser and Ernst. In conclusion, we describe the nature of the exact solutions constructible in a finite number of steps with the available methods

  7. Determination of pKa and the corresponding structures of quinclorac using combined experimental and theoretical approaches

    Song, Dean; Sun, Huiqing; Jiang, Xiaohua; Kong, Fanyu; Qiang, Zhimin; Zhang, Aiqian; Liu, Huijuan; Qu, Jiuhui

    2018-01-01

    As an emerging environmental contaminant, the herbicide quinclorac has attracted much attention in recent years. However, a very fundamental issue, the acid dissociation of quinclorac has not yet to be studied in detail. Herein, the pKa value and the corresponding structures of quinclorac were systematically investigated using combined experimental and theoretical approaches. The experimental pKa of quinclorac was determined by the spectrophotometric method to be 2.65 at 25 °C with ionic strength of 0.05 M, and was corrected to be 2.56 at ionic strength of zero. The molecular structures of quinclorac were then located by employing the DFT calculation. The anionic quinclorac was directly located with the carboxylic group perpendicular to the aromatic ring, while neutral quinclorac was found to be the equivalent twin structures. The result was further confirmed by analyzing the UV/Vis and MS-MS2 spectra from both experimental and theoretical viewpoints. By employing the QSPR approach, the theoretical pKa of QCR was determined to be 2.50, which is excellent agreement with the experimental result obtained herein. The protonation of QCR at the carboxylic group instead of the quinoline structure was attributed to the weak electronegative property of nitrogen atom induced by the electron-withdrawing groups. It is anticipated that this work could not only help in gaining a deep insight into the acid dissociation of quinclorac but also offering the key information on its reaction and interaction with others.

  8. A new theoretical approach to analyze complex processes in cytoskeleton proteins.

    Li, Xin; Kolomeisky, Anatoly B

    2014-03-20

    Cytoskeleton proteins are filament structures that support a large number of important biological processes. These dynamic biopolymers exist in nonequilibrium conditions stimulated by hydrolysis chemical reactions in their monomers. Current theoretical methods provide a comprehensive picture of biochemical and biophysical processes in cytoskeleton proteins. However, the description is only qualitative under biologically relevant conditions because utilized theoretical mean-field models neglect correlations. We develop a new theoretical method to describe dynamic processes in cytoskeleton proteins that takes into account spatial correlations in the chemical composition of these biopolymers. Our approach is based on analysis of probabilities of different clusters of subunits. It allows us to obtain exact analytical expressions for a variety of dynamic properties of cytoskeleton filaments. By comparing theoretical predictions with Monte Carlo computer simulations, it is shown that our method provides a fully quantitative description of complex dynamic phenomena in cytoskeleton proteins under all conditions.

  9. ORGANIZATIONAL WORK GROUPS AND WORK TEAMS – APPROACHES AND DIFFERENCES

    Raluca ZOLTAN

    2015-02-01

    Full Text Available Work groups and work teams represents basic structures of traditional and modern organizations, and during the time they have been intensively researched. However, managers often do not always consider the fundamental differences between groups and teams, which will lead to unrealistic goals and results below expectations. Thus, in the present paper we propose a review of the main researching approaches on groups and teams (psychosocial, socio-technical, and behavioral approach, in the third part of the paper being detailed the fundamental differences between groups and teams in the light of these approaches.

  10. EVOLUTION OF THEORETICAL APPROACHES TO THE DEFINITION OF THE CATEGORY “PERSONNEL POTENTIAL”

    Аlexandra Deshchenko

    2016-02-01

    Full Text Available The article describes the evolution of theoretical approaches to definition of the category «personnel potential» based on the analysis of approaches to definition of the conceptual apparatus of labor Economics, including such categories as: labor force, labor resources, labor potential, human resources, human capital, human capital different authors. The analysis of the evolution of the terms in accordance with the stages of development of a society.

  11. THE REPURCHASE OF SHARES - ANOTHER FORM OF REWARDING INVESTORS - A THEORETICAL APPROACH

    PRISACARIU Maria

    2013-06-01

    Full Text Available Among the shareholder remuneration policies, in recent years, share repurchases are gaining more and more ground. Like any other phenomenon or financial practice, repurchases lacked no theories to explain their motivation, effects and controversies. This paper proposes a theoretical approach to the subject by summarizing relevant research in order to highlight the motivations behind this decision and its implications.

  12. THEORETICAL AND METHODOLOGICAL APPROACHES TO THE STUDY OF PROTEST ACTIVITY IN THE WESTERN SOCIOLOGICAL THOUGHT

    Купрєєва, Ю. О.

    2015-01-01

    In this article the author discusses the main theoretical and methodological approaches to the study of protest activity. Among them - the theory of collective behavior, the relative deprivation theory, the new social movements theory and the resource mobilization theory. Highlighted their strengths and weaknesses. Focused on the new direction of protest studies connected with the development of the Internet.

  13. Supporting Unemployed, Middle-Aged Men: A Psychoeducational Group Approach

    Murphey, Charlotte M.; Shillingford, M. Ann

    2012-01-01

    This article presents a comprehensive group counseling approach to support unemployed, middle-aged men. An inclusive group curriculum designed to provide support and address potential mental health issues related to unemployment is introduced. The focus of the group is divided into 6 major areas that research has shown to have a significant impact…

  14. A Group Approach in a Community Empowerment: A Case Study of Waste Recycling Group in Jakarta

    Hadiyanti, Puji

    2016-01-01

    This study reviews a group approach in empowering the community through waste recycling activities related to the development of human resources in Jakarta. The specific objectives to be achieved are the wish to understand and find: (1) Conditions of waste recycling empowerment in Jakarta, (2) Mechanisms of a group approach in empowering…

  15. Bovine serum albumin adsorption onto functionalized polystyrene lattices: A theoretical modeling approach and error analysis

    Beragoui, Manel; Aguir, Chadlia; Khalfaoui, Mohamed; Enciso, Eduardo; Torralvo, Maria José; Duclaux, Laurent; Reinert, Laurence; Vayer, Marylène; Ben Lamine, Abdelmottaleb

    2015-03-01

    The present work involves the study of bovine serum albumin adsorption onto five functionalized polystyrene lattices. The adsorption measurements have been carried out using a quartz crystal microbalance. Poly(styrene-co-itaconic acid) was found to be an effective adsorbent for bovine serum albumin molecule adsorption. The experimental isotherm data were analyzed using theoretical models based on a statistical physics approach, namely monolayer, double layer with two successive energy levels, finite multilayer, and modified Brunauer-Emmet-Teller. The equilibrium data were then analyzed using five different non-linear error analysis methods and it was found that the finite multilayer model best describes the protein adsorption data. Surface characteristics, i.e., surface charge density and number density of surface carboxyl groups, were used to investigate their effect on the adsorption capacity. The combination of the results obtained from the number of adsorbed layers, the number of adsorbed molecules per site, and the thickness of the adsorbed bovine serum albumin layer allows us to predict that the adsorption of this protein molecule can also be distinguished by monolayer or multilayer adsorption with end-on, side-on, and overlap conformations. The magnitudes of the calculated adsorption energy indicate that bovine serum albumin molecules are physisorbed onto the adsorbent lattices.

  16. THEORETICAL AND METHODICAL APPROACHES TO THE FORMATION AND EVALUATION OF THE QUALITY OF TOURIST SERVICES

    Nataliya Vasylykha

    2017-12-01

    Full Text Available The study, the results of which are described in the article, is devoted to analysing and substantiating approaches to the assessment and quality assurance of tourism services, which form their competitiveness, namely factors and indicators of quality. After all, the integration and globalization of the world society determine the development of tourism as a catalyst for these global processes, and world practice has proved that tourism can be an effective way to solve many socio-economic problems. The subject of the study is the peculiarities of assessing the quality of tourist services. Methodology. The methodological basis of the work is a system of general scientific and special scientific methods, mainly, in the process of research, there are used such methods as system-analytical and dialectical methods – for the theoretical generalization of the investigated material; structural and logical method – in systematizing factors and indicators of the quality of tourist services. The purpose of the article is a theoretical justification of approaches to the quality of tourist services and optimization of their quality assessment. In the research, approaches to the interpretation of the concept of quality are presented and analysed, features of services in general and tourism in particular are concentrated, and it is suggested to group and classify factors and indicators of their quality. The interpretation of the notion of quality is ambiguous, both in Ukrainian and in foreign literary sources, and depends on the point of view on this notion. In our opinion, the most thorough definition characterizes the quality of products and services as a complex feature that determines their suitability to the needs of the consumer. Taking into account the specificity of the term “service”, peculiarities determining the approaches to their evaluation are studied, such a service can be considered a product dominated by intangible elements and also

  17. The person-oriented approach: A short theoretical and practical guide

    Lars R. Bergman

    2014-05-01

    Full Text Available A short overview of the person-oriented approach is given as a guide to the researcher interested in carrying out person-oriented research. Theoretical, methodological, and practical considerations of the approach are discussed. First, some historical roots are traced, followed by a description of the holisticinteractionistic research paradigm, which provided the general framework for the development of the modern person-oriented approach. The approach has both a theoretical and a methodological facet and after presenting its key theoretical tenets, an overview is given of some common person-oriented methods. Central to the person-oriented approach is a system view with its components together forming a pattern regarded as indivisible. This pattern should be understood and studied as a whole, not broken up into pieces (variables that are studied as separate entities. Hence, usually methodological tools are used by which whole patterns are analysed (e.g. cluster analysis. An empirical example is given where the pattern development of school grades is studied.

  18. Theoretical Approaches in Evolutionary Ecology: Environmental Feedback as a Unifying Perspective.

    Lion, Sébastien

    2018-01-01

    Evolutionary biology and ecology have a strong theoretical underpinning, and this has fostered a variety of modeling approaches. A major challenge of this theoretical work has been to unravel the tangled feedback loop between ecology and evolution. This has prompted the development of two main classes of models. While quantitative genetics models jointly consider the ecological and evolutionary dynamics of a focal population, a separation of timescales between ecology and evolution is assumed by evolutionary game theory, adaptive dynamics, and inclusive fitness theory. As a result, theoretical evolutionary ecology tends to be divided among different schools of thought, with different toolboxes and motivations. My aim in this synthesis is to highlight the connections between these different approaches and clarify the current state of theory in evolutionary ecology. Central to this approach is to make explicit the dependence on environmental dynamics of the population and evolutionary dynamics, thereby materializing the eco-evolutionary feedback loop. This perspective sheds light on the interplay between environmental feedback and the timescales of ecological and evolutionary processes. I conclude by discussing some potential extensions and challenges to our current theoretical understanding of eco-evolutionary dynamics.

  19. The Theoretical and Empirical Approaches to the Definition of Audit Risk

    Berezhniy Yevgeniy B.

    2017-12-01

    Full Text Available The risk category is one of the key factors in planning the audit and assessing its results. The article is aimed at generalizing the theoretical and empirical approaches to the definition of audit risk and methods of its reduction. The structure of audit risk was analyzed and it has been determined, that each of researchers approached to structuring of audit risk from the subjective point of view. The author’s own model of audit risk has been proposed. The basic methods of assessment of audit risk are generalized, the theoretical and empirical approaches to its definition are allocated, also it is noted, that application of any of the given models can be suitable rather for approximate estimation, than for exact calculation of an audit risk, as it is accompanied by certain shortcomings.

  20. Understanding employee motivation and organizational performance: Arguments for a set-theoretic approach

    Michael T. Lee

    2016-09-01

    Full Text Available Empirical evidence demonstrates that motivated employees mean better organizational performance. The objective of this conceptual paper is to articulate the progress that has been made in understanding employee motivation and organizational performance, and to suggest how the theory concerning employee motivation and organizational performance may be advanced. We acknowledge the existing limitations of theory development and suggest an alternative research approach. Current motivation theory development is based on conventional quantitative analysis (e.g., multiple regression analysis, structural equation modeling. Since researchers are interested in context and understanding of this social phenomena holistically, they think in terms of combinations and configurations of a set of pertinent variables. We suggest that researchers take a set-theoretic approach to complement existing conventional quantitative analysis. To advance current thinking, we propose a set-theoretic approach to leverage employee motivation for organizational performance.

  1. Topological charge on the lattice: a field theoretical view of the geometrical approach

    Rastelli, L.; Rossi, P.; Vicari, E.

    1997-01-01

    We construct sequences of ''field theoretical'' lattice topological charge density operators which formally approach geometrical definitions in 2D CP N-1 models and 4D SU(N) Yang-Mills theories. The analysis of these sequences of operators suggests a new way of looking at the geometrical method, showing that geometrical charges can be interpreted as limits of sequences of field theoretical (analytical) operators. In perturbation theory, renormalization effects formally tend to vanish along such sequences. But, since the perturbative expansion is asymptotic, this does not necessarily lead to well-behaved geometrical limits. It indeed leaves open the possibility that non-perturbative renormalizations survive. (orig.)

  2. Different Approaches to Cross-Lingual Focus Groups

    Maira Quintanilha

    2015-12-01

    Full Text Available Focus groups are a useful data-generation strategy in qualitative health research when it is important to understand how social contexts shape participants’ health. However, when cross-lingual focus groups are conducted across cultural groups, and in languages in which the researcher is not fluent, questions regarding the usefulness and rigor of the findings can be raised. In this article, we will discuss three different approaches to cross-lingual focus groups used in a community-based participatory research project with pregnant and postpartum, African immigrant women in Alberta, Canada. In two approaches, we moderated focus groups in women’s mother tongue with the support of real-time interpreters, but in the first approach, audio recording was used and in the second approach, audio recording was not used. In the third approach, a bilingual moderator facilitated focus groups in women’s mother tongue, with transcription and translation of audio-recorded data upon completion of data generation. We will describe each approach in detail, including their advantages and challenges, and recontextualize what we have learned within the known literature. We expect the lessons learned in this project may assist others in planning and implementing cross-lingual focus groups, especially in the context of community-based participatory research.

  3. Merged ontology for engineering design: Contrasting empirical and theoretical approaches to develop engineering ontologies

    Ahmed, Saeema; Storga, M

    2009-01-01

    to developing the ontology engineering design integrated taxonomies (EDIT) with a theoretical approach in which concepts and relations are elicited from engineering design theories ontology (DO) The limitations and advantages of each approach are discussed. The research methodology adopted is to map......This paper presents a comparison of two previous and separate efforts to develop an ontology in the engineering design domain, together with an ontology proposal from which ontologies for a specific application may be derived. The research contrasts an empirical, user-centered approach...

  4. Activities of the theoretical nuclear physics group of the Atomic Energy National Commission

    Reich, S.L.

    1982-01-01

    The theoretical studies that have been made in the Atomic Energy National Commission of Argentina about nuclear reactions, nuclear field theories, boson techniques and Hartree-Fock approximation, etc., are reported. (L.C.) [pt

  5. A cultural psychological approach to evangelical faith healing groups

    van Saane, J.W.

    2010-01-01

    From the perspective of Belzen, a cultural approach for the psychology of religion is necessary to cope with the multiplicity of the religious phenomenon. He presents research of specific - very closed - religious groups to illustrate this point. A cultural approach is not limited to these specific

  6. Introducing Farouk's Process Consultation Group Approach in Irish Primary Schools

    Hayes, Marie; Stringer, Phil

    2016-01-01

    Research has shown that teacher consultation groups increase teachers' behaviour management skills through discussion and collaborative problem-solving. Unlike the United Kingdom, at the time of this research consultation groups were not widely used in Irish schools. This research introduced Farouk's process consultation approach in three Irish…

  7. Functional renormalization group approach to the two dimensional Bose gas

    Sinner, A; Kopietz, P [Institut fuer Theoretische Physik, Universitaet Frankfurt, Max-von-Laue Strasse 1, 60438 Frankfurt (Germany); Hasselmann, N [International Center for Condensed Matter Physics, Universidade de BrasIlia, Caixa Postal 04667, 70910-900 BrasIlia, DF (Brazil)], E-mail: hasselma@itp.uni-frankfurt.de, E-mail: sinner@itp.uni-frankfurt.de

    2009-02-01

    We investigate the small frequency and momentum structure of the weakly interacting Bose gas in two dimensions using a functional renormalization group approach. The flow equations are derived within a derivative approximation of the effective action up to second order in spatial and temporal variables and investigated numerically. The truncation we employ is based on the perturbative structure of the theory and is well described as a renormalization group enhanced perturbation theory. It allows to calculate corrections to the Bogoliubov spectrum and to investigate the damping of quasiparticles. Our approach allows to circumvent the divergences which plague the usual perturbative approach.

  8. Theoretical study of chlordecone and surface groups interaction in an activated carbon model under acidic and neutral conditions.

    Gamboa-Carballo, Juan José; Melchor-Rodríguez, Kenia; Hernández-Valdés, Daniel; Enriquez-Victorero, Carlos; Montero-Alejo, Ana Lilian; Gaspard, Sarra; Jáuregui-Haza, Ulises Javier

    2016-04-01

    Activated carbons (ACs) are widely used in the purification of drinking water without almost any knowledge about the adsorption mechanisms of the persistent organic pollutants. Chlordecone (CLD, Kepone) is an organochlorinated synthetic compound that has been used mainly as agricultural insecticide. CLD has been identified and listed as a persistent organic pollutant by the Stockholm Convention. The selection of the best suited AC for this type of contaminants is mainly an empirical and costly process. A theoretical study of the influence of AC surface groups (SGs) on CLD adsorption is done in order to help understanding the process. This may provide a first selection criteria for the preparation of AC with suitable surface properties. A model of AC consisting of a seven membered ring graphene sheet (coronene) with a functional group on the edge was used to evaluate the influence of the SGs over the adsorption. Multiple Minima Hypersurface methodology (MMH) coupled with PM7 semiempirical Hamiltonian was employed in order to study the interactions of the chlordecone with SGs (hydroxyl and carboxyl) at acidic and neutral pH and different hydration conditions. Selected structures were re-optimized using CAM-B3LYP to achieve a well-defined electron density to characterize the interactions by the Quantum Theory of Atoms in Molecules approach. The deprotonated form of surface carboxyl and hydroxyl groups of AC models show the strongest interactions, suggesting a chemical adsorption. An increase in carboxylic SGs content is proposed to enhance CLD adsorption onto AC at neutral pH conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Field theoretical approach to proton-nucleus reactions: II-Multiple-step excitation process

    Eiras, A.; Kodama, T.; Nemes, M.

    1989-01-01

    A field theoretical formulation to multiple step excitation process in proton-nucleus collision within the context of a relativistic eikonal approach is presented. A closed form expression for the double differential cross section can be obtained whose structure is very simple and makes the physics transparent. Glauber's formulation of the same process is obtained as a limit of ours and the necessary approximations are studied and discussed. (author) [pt

  10. Theoretical approach to the destruction or sterilization of drugs in aqueous solution

    Slegers, Catherine; Tilquin, Bernard

    2005-01-01

    Two novel applications in the radiation processing of aqueous solutions of drugs are the sterilization of injectable drugs and the decontamination of hospital wastewaters by ionizing radiation. The parameters influencing the destruction of the drug in aqueous solutions are studied with a computer simulation program. This theoretical approach has revealed that the dose rate is the most important parameter that can be easily varied in order to optimize the destruction or the protection of the drug

  11. A THEORETICAL APPROACH TO THE TRANSITION FROM A RESOURCE BASED TO A KNOWLEDGE-ECONOMY

    Diana GIOACASI

    2015-09-01

    Full Text Available Economic development and the emergence of new technologies have changed the optics on the factors that are generating added value. The transition from a resource-dependent economy to one focused on tangible non-financial factors has progressed in a gradual manner and took place under the influence of globalization and of the internet boom. The aim of this article is to provide a theoretical approach to this phenomenon from the perspective of the temporal evolution of enterprise resources.

  12. A Theoretical Assessment of the Formation of IT clusters in Kazakhstan: Approaches and Positive Effects

    Anel A. Kireyeva

    2016-01-01

    Abstract The aim of this research is to develop new theoretical approaches of the formation of IT clusters in order to strengthen of trend of the innovative industrialization and competitiveness of the country. Keeping with the previous literature, this study determines by the novelty of the problem, concerning the formation of IT clusters, which can become a driving force of transformation due to the interaction, improving efficiency and introducing advanced technology. In this research,...

  13. A Balanced Theoretical and Empirical Approach for the Development of a Design Support Tool

    Jensen, Thomas Aakjær; Hansen, Claus Thorp

    1996-01-01

    The introduction of a new design support system may change the engineering designer's work situation. Therefore, it may not be possible to derive all the functionalities for a design support system from solely empirical studies of manual design work. Alternatively the design support system could ...... system, indicating a proposal for how to balance a theoretical and empirical approach. The result of this research will be utilized in the development of a Designer's Workbench to support the synthesis activity in mechanical design....

  14. Decision support models for solid waste management: Review and game-theoretic approaches

    Karmperis, Athanasios C.; Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios

    2013-01-01

    Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed

  15. Decision support models for solid waste management: Review and game-theoretic approaches

    Karmperis, Athanasios C., E-mail: athkarmp@mail.ntua.gr [Sector of Industrial Management and Operational Research, School of Mechanical Engineering, National Technical University of Athens, Iroon Polytechniou 9, 15780 Athens (Greece); Army Corps of Engineers, Hellenic Army General Staff, Ministry of Defence (Greece); Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios [Sector of Industrial Management and Operational Research, School of Mechanical Engineering, National Technical University of Athens, Iroon Polytechniou 9, 15780 Athens (Greece)

    2013-05-15

    Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed.

  16. A game-theoretic approach to real-time system testing

    David, Alexandre; Larsen, Kim Guldstrand; Li, Shuhao

    2008-01-01

    This paper presents a game-theoretic approach to the testing of uncontrollable real-time systems. By modelling the systems with Timed I/O Game Automata and specifying the test purposes as Timed CTL formulas, we employ a recently developed timed game solver UPPAAL-TIGA to synthesize winning...... strategies, and then use these strategies to conduct black-box conformance testing of the systems. The testing process is proved to be sound and complete with respect to the given test purposes. Case study and preliminary experimental results indicate that this is a viable approach to uncontrollable timed...... system testing....

  17. Health Professionals' Explanations of Suicidal Behaviour: Effects of Professional Group, Theoretical Intervention Model, and Patient Suicide Experience.

    Rothes, Inês Areal; Henriques, Margarida Rangel

    2017-12-01

    In a help relation with a suicidal person, the theoretical models of suicidality can be essential to guide the health professional's comprehension of the client/patient. The objectives of this study were to identify health professionals' explanations of suicidal behaviors and to study the effects of professional group, theoretical intervention models, and patient suicide experience in professionals' representations. Two hundred and forty-two health professionals filled out a self-report questionnaire. Exploratory principal components analysis was used. Five explanatory models were identified: psychological suffering, affective cognitive, sociocommunicational, adverse life events, and psychopathological. Results indicated that the psychological suffering and psychopathological models were the most valued by the professionals, while the sociocommunicational was seen as the least likely to explain suicidal behavior. Differences between professional groups were found. We concluded that training and reflection on theoretical models in general and in communicative issues in particular are needed in the education of health professionals.

  18. Theoretical Background for Predicting the Properties of Petroleum Fluids via Group Contribution Methods

    Bogdanić, Grozdana; Pavlíček, Jan; Wichterle, Ivan

    2012-01-01

    Roč. 42, SI (2012), s. 1873-1878 E-ISSN 1877-7058. [International Congress of Chemical and Process Engineering CHISA 2012 and 15th Conference PRES 2012 /20./. Prague, 25.08.2012-29.08.2012] Institutional support: RVO:67985858 Keywords : petroleum fluids * prediction * physico-chemical properties Subject RIV: CF - Physical ; Theoretical Chemistry

  19. User and Document Group Approach of Clustering in Tagging Systems

    Pan, Rong; Xu, Guandong; Dolog, Peter

    2010-01-01

    In this paper, we propose a spectral clustering approach for users and documents group modeling in order to capture the common preference and relatedness of users and documents, and to reduce the time complexity of similarity calculations. In experiments, we investigate the selection of the optim...... amount of clusters. We also show a reduction of the time consuming in calculating the similarity for the recommender systems by selecting a centroid first, and then compare the inside item on behalf of each group....

  20. Reflective practice and vocational training: theoretical approaches in the field of Health and Nursing

    Luciana Netto

    2018-02-01

    Full Text Available Abstract Objective: Theoretical reflection that uses Reflexivity as a theoretical reference and its objective is to approach Donald Schön's reflective thinking, interrelating it with the innovative curriculum. Method: The writings of Schön and other authors who addressed the themes in their works were used. Results: The innovative curriculum as an expression of dissatisfaction with the fragmentation paradigm may favor reflective practice, since it is necessary to mobilize reflexivity for actions and contexts that are unpredictable in the field of health promotion. Conclusions: The innovative curriculum favors and is favored by a reflective practice and the development of competencies for the promotion of health. Implications for practice: The findings apply to the practice of nurses to deal with the conditioning and determinants of the health-disease process.

  1. Forming Limits in Sheet Metal Forming for Non-Proportional Loading Conditions - Experimental and Theoretical Approach

    Ofenheimer, Aldo; Buchmayr, Bruno; Kolleck, Ralf; Merklein, Marion

    2005-01-01

    The influence of strain paths (loading history) on material formability is well known in sheet forming processes. Sophisticated experimental methods are used to determine the entire shape of strain paths of forming limits for aluminum AA6016-T4 alloy. Forming limits for sheet metal in as-received condition as well as for different pre-deformation are presented. A theoretical approach based on Arrieux's intrinsic Forming Limit Stress Curve (FLSC) concept is employed to numerically predict the influence of loading history on forming severity. The detailed experimental strain paths are used in the theoretical study instead of any linear or bilinear simplified loading histories to demonstrate the predictive quality of forming limits in the state of stress

  2. Alternative sources of power generation, incentives and regulatory mandates: a theoretical approach to the Colombian case

    Zapata, Carlos M; Zuluaga Monica M; Dyner, Isaac

    2005-01-01

    Alternative Energy Generation Sources are turning relevant in several countries worldwide because of technology improvement and the environmental treatment. In this paper, the most common problems of renewable energy sources are accomplished, different incentives and regulatory mandates from several countries are exposed, and a first theoretical approach to a renewable energies incentive system in Colombia is discussed. The paper is fundamentally in theoretical aspects and international experience in renewable energies incentives to accelerate their diffusion; features are analyzed towards a special incentive system for renewable energies in Colombia. As a conclusion, in Colombia will be apply indirect incentives like low interest rate, taxes exemptions and so on. But these incentives are applied to limit the support of electricity productivity in generating organizations.

  3. A short course in quantum information theory an approach from theoretical physics

    Diosi, Lajos

    2011-01-01

    This short and concise primer takes the vantage point of theoretical physics and the unity of physics. It sets out to strip the burgeoning field of quantum information science to its basics by linking it to universal concepts in physics. An extensive lecture rather than a comprehensive textbook, this volume is based on courses delivered over several years to advanced undergraduate and beginning graduate students, but essentially it addresses anyone with a working knowledge of basic quantum physics. Readers will find these lectures a most adequate entry point for theoretical studies in this field. For the second edition, the authors has succeeded in adding many new topics while sticking to the conciseness of the overall approach. A new chapter on qubit thermodynamics has been added, while new sections and subsections have been incorporated in various chapter to deal with weak and time-continuous measurements, period-finding quantum algorithms and quantum error corrections. From the reviews of the first edition...

  4. An Informal Overview of the Unitary Group Approach

    Sonnad, V.; Escher, J.; Kruse, M.; Baker, R.

    2016-01-01

    The Unitary Groups Approach (UGA) is an elegant and conceptually unified approach to quantum structure calculations. It has been widely used in molecular structure calculations, and holds the promise of a single computational approach to structure calculations in a variety of different fields. We explore the possibility of extending the UGA to computations in atomic and nuclear structure as a simpler alternative to traditional Racah algebra-based approaches. We provide a simple introduction to the basic UGA and consider some of the issues in using the UGA with spin-dependent, multi-body Hamiltonians requiring multi-shell bases adapted to additional symmetries. While the UGA is perfectly capable of dealing with such problems, it is seen that the complexity rises dramatically, and the UGA is not at this time, a simpler alternative to Racah algebra-based approaches.

  5. What is new in the study of differential equations by group theoretical methods

    Winternitz, P.

    1986-11-01

    Several recent developments have made the application of group theory to the solving of differential equations more powerful than it used to be. The ones discussed here are: 1. The advent of symbol manipulating computer languages that greatly simplify the construction of the symmetry group of an equation 2. Methods of finding all subgroups of a given Lie symmetry group 3. The theory of infinite dimensional Lie algebras 4. The combination of group theory and singularity analysis

  6. An Analysis of Small Group Interactions of Vietnamese Students under the Bourdieusian Theoretical Lens

    Pham, Thanh; Pham, Lam

    2018-01-01

    Group work has been increasingly encouraged and applied in Vietnamese universities. However, very little has been known about how Vietnamese university students work in a group and what the conditions are that help establish an effective group. This study attempted to redress this gap. The research applied Bourdieu's social field theory to examine…

  7. Theoretical analysis of integral neutron transport equation using collision probability method with quadratic flux approach

    Shafii, Mohammad Ali; Meidianti, Rahma; Wildian,; Fitriyani, Dian; Tongkukut, Seni H. J.; Arkundato, Artoto

    2014-01-01

    Theoretical analysis of integral neutron transport equation using collision probability (CP) method with quadratic flux approach has been carried out. In general, the solution of the neutron transport using the CP method is performed with the flat flux approach. In this research, the CP method is implemented in the cylindrical nuclear fuel cell with the spatial of mesh being conducted into non flat flux approach. It means that the neutron flux at any point in the nuclear fuel cell are considered different each other followed the distribution pattern of quadratic flux. The result is presented here in the form of quadratic flux that is better understanding of the real condition in the cell calculation and as a starting point to be applied in computational calculation

  8. Theoretical analysis of integral neutron transport equation using collision probability method with quadratic flux approach

    Shafii, Mohammad Ali, E-mail: mashafii@fmipa.unand.ac.id; Meidianti, Rahma, E-mail: mashafii@fmipa.unand.ac.id; Wildian,, E-mail: mashafii@fmipa.unand.ac.id; Fitriyani, Dian, E-mail: mashafii@fmipa.unand.ac.id [Department of Physics, Andalas University Padang West Sumatera Indonesia (Indonesia); Tongkukut, Seni H. J. [Department of Physics, Sam Ratulangi University Manado North Sulawesi Indonesia (Indonesia); Arkundato, Artoto [Department of Physics, Jember University Jember East Java Indonesia (Indonesia)

    2014-09-30

    Theoretical analysis of integral neutron transport equation using collision probability (CP) method with quadratic flux approach has been carried out. In general, the solution of the neutron transport using the CP method is performed with the flat flux approach. In this research, the CP method is implemented in the cylindrical nuclear fuel cell with the spatial of mesh being conducted into non flat flux approach. It means that the neutron flux at any point in the nuclear fuel cell are considered different each other followed the distribution pattern of quadratic flux. The result is presented here in the form of quadratic flux that is better understanding of the real condition in the cell calculation and as a starting point to be applied in computational calculation.

  9. Quantum group structure and local fields in the algebraic approach to 2D gravity

    Schnittger, Jens

    1994-01-01

    This review contains a summary of work by J.-L. Gervais and the author on the operator approach to 2d gravity. Special emphasis is placed on the construction of local observables -the Liouville exponentials and the Liouville field itself - and the underlying algebra of chiral vertex operators. The double quantum group structure arising from the presence of two screening charges is discussed and the generalized algebra and field operators are derived. In the last part, we show that our construction gives rise to a natural definition of a quantum tau function, which is a noncommutative version of the classical group-theoretic representation of the Liouville fields by Leznov and Saveliev.

  10. Tobacco Cessation for Adolescents: Developing a Group Therapy Approach.

    Moolchan, Eric T.; Ruckel, Susan J.

    2002-01-01

    Describes a cognitive-behavioral therapeutic approach to help teenagers better manage life stressors by using effective and adaptive coping skills, while identifying and addressing specific factors that lead either to smoking or maintaining abstinence from smoking behavior. Discusses specific group exercises that empower teens to take control of…

  11. Group theoretical construction of two-dimensional models with infinite sets of conservation laws

    D'Auria, R.; Regge, T.; Sciuto, S.

    1980-01-01

    We explicitly construct some classes of field theoretical 2-dimensional models associated with symmetric spaces G/H according to a general scheme proposed in an earlier paper. We treat the SO(n + 1)/SO(n) and SU(n + 1)/U(n) case, giving their relationship with the O(n) sigma-models and the CP(n) models. Moreover, we present a new class of models associated to the SU(n)/SO(n) case. All these models are shown to possess an infinite set of local conservation laws. (orig.)

  12. A review of the nurtured heart approach to parenting: evaluation of its theoretical and empirical foundations.

    Hektner, Joel M; Brennan, Alison L; Brotherson, Sean E

    2013-09-01

    The Nurtured Heart Approach to parenting (NHA; Glasser & Easley, 2008) is summarized and evaluated in terms of its alignment with current theoretical perspectives and empirical evidence in family studies and developmental science. Originally conceived and promoted as a behavior management approach for parents of difficult children (i.e., with behavior disorders), NHA is increasingly offered as a valuable strategy for parents of any children, despite a lack of published empirical support. Parents using NHA are trained to minimize attention to undesired behaviors, provide positive attention and praise for compliance with rules, help children be successful by scaffolding and shaping desired behavior, and establish a set of clear rules and consequences. Many elements of the approach have strong support in the theoretical and empirical literature; however, some of the assumptions are more questionable, such as that negative child behavior can always be attributed to unintentional positive reinforcement by parents responding with negative attention. On balance, NHA appears to promote effective and validated parenting practices, but its effectiveness now needs to be tested empirically. © FPI, Inc.

  13. Evolution of the Theoretical Approaches to Disclosing the Economic Substance of Accumulation of Capital

    Yemets Vadym V.

    2016-05-01

    Full Text Available The article proposes a classification for periods of evolution of theoretical approaches to disclosing the economic substance of accumulation of capital, taking into account the civilizational approach to the development of society. The author has proposed five stages in the evolution of theoretical approaches, which are closely related to the development of economy and stipulate dominance of a certain form of accumulation of capital. So, the first stage (time period B.C. – the 5th Century is referred to as Individual-social significance of accumulation of capital; the second stage (from the 6th century to the 16th century – Accumulation of monetary capitals; the third stage (from the mid-17th century until the end of the 18th century – Industrialproduction accumulation of capital; the fourth stage (from the mid-19th century until the 70s of the 20th century – Investment-oriented accumulation of capital; the fifth stage (from the 70s of the 20th century up to the current period – Globally-intensive accumulation of capital.

  14. Comparative regulatory approaches for groups of new plant breeding techniques.

    Lusser, Maria; Davies, Howard V

    2013-06-25

    This manuscript provides insights into ongoing debates on the regulatory issues surrounding groups of biotechnology-driven 'New Plant Breeding Techniques' (NPBTs). It presents the outcomes of preliminary discussions and in some cases the initial decisions taken by regulators in the following countries: Argentina, Australia, Canada, EU, Japan, South Africa and USA. In the light of these discussions we suggest in this manuscript a structured approach to make the evaluation more consistent and efficient. The issue appears to be complex as these groups of new technologies vary widely in both the technologies deployed and their impact on heritable changes in the plant genome. An added complication is that the legislation, definitions and regulatory approaches for biotechnology-derived crops differ significantly between these countries. There are therefore concerns that this situation will lead to non-harmonised regulatory approaches and asynchronous development and marketing of such crops resulting in trade disruptions. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Theoretical approach for plasma series resonance effect in geometrically symmetric dual radio frequency plasma

    Bora, B.; Bhuyan, H.; Favre, M.; Wyndham, E.; Chuaqui, H.

    2012-01-01

    Plasma series resonance (PSR) effect is well known in geometrically asymmetric capacitively couple radio frequency plasma. However, plasma series resonance effect in geometrically symmetric plasma has not been properly investigated. In this work, a theoretical approach is made to investigate the plasma series resonance effect and its influence on Ohmic and stochastic heating in geometrically symmetric discharge. Electrical asymmetry effect by means of dual frequency voltage waveform is applied to excite the plasma series resonance. The results show considerable variation in heating with phase difference between the voltage waveforms, which may be applicable in controlling the plasma parameters in such plasma.

  16. Using the theoretical domains framework to guide the development of a self-management program for individuals with spinal cord injury: Results from a national stakeholder advisory group.

    Munce, Sarah E P; Allin, Sonya; Wolfe, Dalton L; Anzai, Karen; Linassi, Gary; Noonan, Vanessa K; Jaglal, Susan B

    2017-11-01

    To determine the implementation considerations for a targeted self-management program for individuals with spinal cord injury (SCI) from the perspective of a national stakeholder advisory group using the Theoretical Domains Framework (TDF) as a guide. Qualitative descriptive approach. Two focus groups held at the 6 th National Spinal Cord Injury Conference (October 2-4 th , 2014) in Toronto, Ontario, Canada. A total of 25 stakeholders from across Canada participated in focus groups or "brainstorming sessions". The stakeholders included 5 clinicians, 14 researchers, 3 policy makers, and 3 individuals with SCI. Not applicable. Not applicable. All 14 theoretical domains were identified in the brainstorming sessions. No new themes or domains were identified. The need to consider the theoretical domains of Knowledge, Skills, Reinforcement, Intentions, Goals (e.g. the readiness of the individual with SCI), Environmental Context and Resources (e.g. considerations for governance and ownership of the program and a business model for sustainability), as well as Social Influences (e.g. issues of privacy and security in the context of on-line delivery) was identified. The current study provides complementary results to our previous series of studies on the implementation considerations for the development of a targeted self-management program for individuals with SCI by emphasizing the health care professional/health policy perspective. It is anticipated that such a program could not only reduce secondary complications and subsequent inappropriate health care use but it may also improve the quality of life for individuals with SCI and their caregivers.

  17. A theoretical approach to medication adherence for children and youth with psychiatric disorders.

    Charach, Alice; Volpe, Tiziana; Boydell, Katherine M; Gearing, Robin E

    2008-01-01

    This article provides a theoretical review of treatment adherence for children and youth with psychiatric disorders where pharmacological agents are first-line interventions. Four empirically based models of health behavior are reviewed and applied to the sparse literature about medication adherence for children with attention-deficit/hyperactivity disorder and young people with first-episode psychosis. Three qualitative studies of medication use are summarized, and details from the first-person narratives are used to illustrate the theoretical models. These studies indicate, when taken together, that the clinical approach to addressing poor medication adherence in children and youth with psychiatric disorders should be guided by more than one theoretical model. Mental health experts should clarify beliefs, address misconceptions, and support exploration of alternative treatment options unless contraindicated. Recognizing the larger context of the family, allowing time for parents and children to change their attitudes, and offering opportunities for easy access to medication in the future are important ways of respecting patient preferences, while steering them toward best-evidence interventions. Future research using qualitative methods of inquiry to investigate parent, child, and youth experiences of mental health interventions should identify effective ways to improve treatment adherence.

  18. Group manifold approach to gravity and supergravity theories

    d'Auria, R.; Fre, P.; Regge, T.

    1981-05-01

    Gravity theories are presented from the point of view of group manifold formulation. The differential geometry of groups and supergroups is discussed first; the notion of connection and related Yang-Mills potentials is introduced. Then ordinary Einstein gravity is discussed in the Cartan formulation. This discussion provides a first example which will then be generalized to more complicated theories, in particular supergravity. The distinction between ''pure'' and ''impure' theories is also set forth. Next, the authors develop an axiomatic approach to rheonomic theories related to the concept of Chevalley cohomology on group manifolds, and apply these principles to N = 1 supergravity. Then the panorama of so far constructed pure and impure group manifold supergravities is presented. The pure d = 5 N = 2 case is discussed in some detail, and N = 2 and N = 3 in d = 4 are considered as examples of the impure theories. The way a pure theory becomes impure after dimensional reduction is illustrated. Next, the role of kinematical superspace constraints as a subset of the group-manifold equations of motion is discussed, and the use of this approach to obtain the auxiliary fields is demonstrated. Finally, the application of the group manifold method to supersymmetric Super Yang-Mills theories is addressed

  19. Data Collection for Mobile Group Consumption: An Asynchronous Distributed Approach

    Weiping Zhu

    2016-04-01

    Full Text Available Mobile group consumption refers to consumption by a group of people, such as a couple, a family, colleagues and friends, based on mobile communications. It differs from consumption only involving individuals, because of the complex relations among group members. Existing data collection systems for mobile group consumption are centralized, which has the disadvantages of being a performance bottleneck, having single-point failure and increasing business and security risks. Moreover, these data collection systems are based on a synchronized clock, which is often unrealistic because of hardware constraints, privacy concerns or synchronization cost. In this paper, we propose the first asynchronous distributed approach to collecting data generated by mobile group consumption. We formally built a system model thereof based on asynchronous distributed communication. We then designed a simulation system for the model for which we propose a three-layer solution framework. After that, we describe how to detect the causality relation of two/three gathering events that happened in the system based on the collected data. Various definitions of causality relations based on asynchronous distributed communication are supported. Extensive simulation results show that the proposed approach is effective for data collection relating to mobile group consumption.

  20. Data Collection for Mobile Group Consumption: An Asynchronous Distributed Approach.

    Zhu, Weiping; Chen, Weiran; Hu, Zhejie; Li, Zuoyou; Liang, Yue; Chen, Jiaojiao

    2016-04-06

    Mobile group consumption refers to consumption by a group of people, such as a couple, a family, colleagues and friends, based on mobile communications. It differs from consumption only involving individuals, because of the complex relations among group members. Existing data collection systems for mobile group consumption are centralized, which has the disadvantages of being a performance bottleneck, having single-point failure and increasing business and security risks. Moreover, these data collection systems are based on a synchronized clock, which is often unrealistic because of hardware constraints, privacy concerns or synchronization cost. In this paper, we propose the first asynchronous distributed approach to collecting data generated by mobile group consumption. We formally built a system model thereof based on asynchronous distributed communication. We then designed a simulation system for the model for which we propose a three-layer solution framework. After that, we describe how to detect the causality relation of two/three gathering events that happened in the system based on the collected data. Various definitions of causality relations based on asynchronous distributed communication are supported. Extensive simulation results show that the proposed approach is effective for data collection relating to mobile group consumption.

  1. An approach to grouping species for ecological risk assessment

    Hampton, N.L.; VanHorn, R.L.; Morris, R.; Brewer, R.

    1994-01-01

    The ecological risk assessment (ERA) paradigm acknowledges all levels of ecological organization as having potential for defining assessment and measurement endpoints. However, assessment goals and endpoints are generally concentrated at individual species and population levels. As part of a sitewide, screening-level ERA process at the Idaho National Engineering Laboratory (INEL), a ''functional group'' approach was developed to incorporate assessment at a higher level of ecological organization into the risk analysis process. Functional groups demonstrating biological similarity and similar potential for contaminant exposure were developed using taxonomic, trophic and habitat parameters. As defined, all species are potential surrogates for the other members of the same functional group. Measurement endpoint data for several species may be integrated to address the risk to the group as a whole. The functional group concept was applied throughout the problem formulation, analysis, and risk characterization phases of the assessment process. This approach allows the ERA to be focused on risk to the integrity of individual functional groups, which can subsequently be related to guild and community integrity

  2. Neutrosophic Game Theoretic Approach to Indo-Pak Conflict over Jammu-Kashmir

    Surapati Pramanik

    2014-03-01

    Full Text Available The study deals with the enduring conflict between India and Pakistan over Jammu and Kashmir since 1947. The ongoing conflict is analyzed as an enduring rivalry; characterized by three major wars (1947-48, 1965, 1971, low intensity military conflict (Siachen, mini war at Kargil (1999, internal insurgency, cross border terrorism. We examine the progress and the status of the dispute, as well as the dynamics of the India Pakistan relationship by considering the influence of USA and China in crisis dynamics. We discuss the possible solutions offered by the various study groups and persons. Most of the studies were done in crisp environment. Pramanik and Roy (S. Pramanik and T.K. Roy, Game theoretic model to the Jammu-Kashmir conflict between India and Pakistan. International Journal of Mathematical Archive (IJMA, 4(8 (2013, 162-170. studied game theoretic model toJammu and Kashmir conflict in crisp environment. In the present study we have extended the concept of the game theoric model of the Jammu and Kashmir conflict in neutrosophic envirorment. We have explored the possibilities and developed arguments for an application of principle of neutrosophic game theory to understand properly of the Jammu and Kashmir conflict in terms of goals and strategy of either side. Standard 2×2 zero-sum game theoretic model used to identify an optimal solution.

  3. Quantum noise in the mirror–field system: A field theoretic approach

    Hsiang, Jen-Tsung; Wu, Tai-Hung; Lee, Da-Shin; King, Sun-Kun; Wu, Chun-Hsien

    2013-01-01

    We revisit the quantum noise problem in the mirror–field system by a field-theoretic approach. Here a perfectly reflecting mirror is illuminated by a single-mode coherent state of the massless scalar field. The associated radiation pressure is described by a surface integral of the stress-tensor of the field. The read-out field is measured by a monopole detector, from which the effective distance between the detector and mirror can be obtained. In the slow-motion limit of the mirror, this field-theoretic approach allows to identify various sources of quantum noise that all in all leads to uncertainty of the read-out measurement. In addition to well-known sources from shot noise and radiation pressure fluctuations, a new source of noise is found from field fluctuations modified by the mirror’s displacement. Correlation between different sources of noise can be established in the read-out measurement as the consequence of interference between the incident field and the field reflected off the mirror. In the case of negative correlation, we found that the uncertainty can be lowered than the value predicted by the standard quantum limit. Since the particle-number approach is often used in quantum optics, we compared results obtained by both approaches and examine its validity. We also derive a Langevin equation that describes the stochastic dynamics of the mirror. The underlying fluctuation–dissipation relation is briefly mentioned. Finally we discuss the backreaction induced by the radiation pressure. It will alter the mean displacement of the mirror, but we argue this backreaction can be ignored for a slowly moving mirror. - Highlights: ► The quantum noise problem in the mirror–field system is re-visited by a field-theoretic approach. ► Other than the shot noise and radiation pressure noise, we show there are new sources of noise and correlation between them. ► The noise correlations can be used to suppress the overall quantum noise on the mirror.

  4. Quantum noise in the mirror-field system: A field theoretic approach

    Hsiang, Jen-Tsung, E-mail: cosmology@gmail.com [Department of Physics, National Dong-Hwa University, Hua-lien, Taiwan, ROC (China); Wu, Tai-Hung [Department of Physics, National Dong-Hwa University, Hua-lien, Taiwan, ROC (China); Lee, Da-Shin, E-mail: dslee@mail.ndhu.edu.tw [Department of Physics, National Dong-Hwa University, Hua-lien, Taiwan, ROC (China); King, Sun-Kun [Institutes of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan, ROC (China); Wu, Chun-Hsien [Department of Physics, Soochow University, Taipei, Taiwan, ROC (China)

    2013-02-15

    We revisit the quantum noise problem in the mirror-field system by a field-theoretic approach. Here a perfectly reflecting mirror is illuminated by a single-mode coherent state of the massless scalar field. The associated radiation pressure is described by a surface integral of the stress-tensor of the field. The read-out field is measured by a monopole detector, from which the effective distance between the detector and mirror can be obtained. In the slow-motion limit of the mirror, this field-theoretic approach allows to identify various sources of quantum noise that all in all leads to uncertainty of the read-out measurement. In addition to well-known sources from shot noise and radiation pressure fluctuations, a new source of noise is found from field fluctuations modified by the mirror's displacement. Correlation between different sources of noise can be established in the read-out measurement as the consequence of interference between the incident field and the field reflected off the mirror. In the case of negative correlation, we found that the uncertainty can be lowered than the value predicted by the standard quantum limit. Since the particle-number approach is often used in quantum optics, we compared results obtained by both approaches and examine its validity. We also derive a Langevin equation that describes the stochastic dynamics of the mirror. The underlying fluctuation-dissipation relation is briefly mentioned. Finally we discuss the backreaction induced by the radiation pressure. It will alter the mean displacement of the mirror, but we argue this backreaction can be ignored for a slowly moving mirror. - Highlights: Black-Right-Pointing-Pointer The quantum noise problem in the mirror-field system is re-visited by a field-theoretic approach. Black-Right-Pointing-Pointer Other than the shot noise and radiation pressure noise, we show there are new sources of noise and correlation between them. Black-Right-Pointing-Pointer The noise

  5. Modified economic order quantity (EOQ model for items with imperfect quality: Game-theoretical approaches

    Milad Elyasi

    2014-04-01

    Full Text Available In the recent decade, studying the economic order quantity (EOQ models with imperfect quality has appealed to many researchers. Only few papers are published discussing EOQ models with imperfect items in a supply chain. In this paper, a two-echelon decentralized supply chain consisting of a manufacture and a supplier that both face just in time (JIT inventory problem is considered. It is sought to find the optimal number of the shipments and the quantity of each shipment in a way that minimizes the both manufacturer’s and the supplier’s cost functions. To the authors’ best knowledge, this is the first paper that deals with imperfect items in a decentralized supply chain. Thereby, three different game theoretical solution approaches consisting of two non-cooperative games and a cooperative game are proposed. Comparing the results of three different scenarios with those of the centralized model, the conclusions are drawn to obtain the best approach.

  6. Group theoretical basis of some identities for the generalized hypergeometric series

    Beyer, W.A.; Louck, J.D.; Stein, P.R.

    1987-01-01

    It is shown that Thomae's identity between two 3 F 2 hypergeometric series of unit argument together with the trivial invariance under separate permutations of numerator and denominator parameters implies that the symmetric group S 5 is an invariance group of this series. A similar result is proved for the terminating Saalschuetzian 4 F 3 series, where S 6 is shown to be the invariance group of this series (or S 5 if one parameter is eliminated by using the Saalschuetz condition). Here Bailey's identity is realized as a permutation of appropriately defined parameters. Finally, the set of three-term relations between 3 F 2 series of unit argument discovered by Thomae [J. Thomae, J. Reine Angew. Math. 87, 26 (1879)] and systematized by Whipple [F. J. Whipple, Proc. London Math. Soc. 23, 104 (1925)] is shown to be transformed into itself under the action of the group S 6 x Λ, where Λ is a two-element group. The 12 left cosets of S 6 x Λ with respect to the invariance group S 5 are the structural elements underlying the three-term relations. The symbol manipulator macsyma was used to obtain preliminary results

  7. A minimalist functional group (MFG) approach for surrogate fuel formulation

    Abdul Jameel, Abdul Gani; Naser, Nimal; Issayev, Gani; Touitou, Jamal; Ghosh, Manik Kumer; Emwas, Abdul-Hamid M.; Farooq, Aamir; Dooley, Stephen; Sarathy, Mani

    2018-01-01

    Surrogate fuel formulation has drawn significant interest due to its relevance towards understanding combustion properties of complex fuel mixtures. In this work, we present a novel approach for surrogate fuel formulation by matching target fuel functional groups, while minimizing the number of surrogate species. Five key functional groups; paraffinic CH, paraffinic CH, paraffinic CH, naphthenic CH–CH and aromatic C–CH groups in addition to structural information provided by the Branching Index (BI) were chosen as matching targets. Surrogates were developed for six FACE (Fuels for Advanced Combustion Engines) gasoline target fuels, namely FACE A, C, F, G, I and J. The five functional groups present in the fuels were qualitatively and quantitatively identified using high resolution H Nuclear Magnetic Resonance (NMR) spectroscopy. A further constraint was imposed in limiting the number of surrogate components to a maximum of two. This simplifies the process of surrogate formulation, facilitates surrogate testing, and significantly reduces the size and time involved in developing chemical kinetic models by reducing the number of thermochemical and kinetic parameters requiring estimation. Fewer species also reduces the computational expenses involved in simulating combustion in practical devices. The proposed surrogate formulation methodology is denoted as the Minimalist Functional Group (MFG) approach. The MFG surrogates were experimentally tested against their target fuels using Ignition Delay Times (IDT) measured in an Ignition Quality Tester (IQT), as specified by the standard ASTM D6890 methodology, and in a Rapid Compression Machine (RCM). Threshold Sooting Index (TSI) and Smoke Point (SP) measurements were also performed to determine the sooting propensities of the surrogates and target fuels. The results showed that MFG surrogates were able to reproduce the aforementioned combustion properties of the target FACE gasolines across a wide range of conditions

  8. A minimalist functional group (MFG) approach for surrogate fuel formulation

    Abdul Jameel, Abdul Gani

    2018-03-20

    Surrogate fuel formulation has drawn significant interest due to its relevance towards understanding combustion properties of complex fuel mixtures. In this work, we present a novel approach for surrogate fuel formulation by matching target fuel functional groups, while minimizing the number of surrogate species. Five key functional groups; paraffinic CH, paraffinic CH, paraffinic CH, naphthenic CH–CH and aromatic C–CH groups in addition to structural information provided by the Branching Index (BI) were chosen as matching targets. Surrogates were developed for six FACE (Fuels for Advanced Combustion Engines) gasoline target fuels, namely FACE A, C, F, G, I and J. The five functional groups present in the fuels were qualitatively and quantitatively identified using high resolution H Nuclear Magnetic Resonance (NMR) spectroscopy. A further constraint was imposed in limiting the number of surrogate components to a maximum of two. This simplifies the process of surrogate formulation, facilitates surrogate testing, and significantly reduces the size and time involved in developing chemical kinetic models by reducing the number of thermochemical and kinetic parameters requiring estimation. Fewer species also reduces the computational expenses involved in simulating combustion in practical devices. The proposed surrogate formulation methodology is denoted as the Minimalist Functional Group (MFG) approach. The MFG surrogates were experimentally tested against their target fuels using Ignition Delay Times (IDT) measured in an Ignition Quality Tester (IQT), as specified by the standard ASTM D6890 methodology, and in a Rapid Compression Machine (RCM). Threshold Sooting Index (TSI) and Smoke Point (SP) measurements were also performed to determine the sooting propensities of the surrogates and target fuels. The results showed that MFG surrogates were able to reproduce the aforementioned combustion properties of the target FACE gasolines across a wide range of conditions

  9. Supply chain collaboration: A Game-theoretic approach to profit allocation

    Ponte, B.; Fernández, I.; Rosillo, R.; Parreño, J.; García, N.

    2016-07-01

    Purpose: This paper aims to develop a theoretical framework for profit allocation, as a mechanism for aligning incentives, in collaborative supply chains. Design/methodology/approach: The issue of profit distribution is approached from a game-theoretic perspective. We use the nucleolus concept. The framework is illustrated through a numerical example based on the Beer Game scenario. Findings: The nucleolus offers a powerful perspective to tackle this problem, as it takes into consideration the bargaining power of the different echelons. We show that this framework outperforms classical alternatives. Research limitations/implications: The allocation of the overall supply chain profit is analyzed from a static perspective. Considering the dynamic nature of the problem would be an interesting next step. Practical implications: We provide evidence of drawbacks derived from classical solutions to the profit allocation problem. Real-world collaborative supply chains need of robust mechanisms like the one tackled in this work to align incentives from the various actors. Originality/value: Adopting an efficient collaborative solution is a major challenge for supply chains, since it is a wide and complex process that requires an appropriate scheme. Within this framework, profit allocation is essential.

  10. A Game-theoretical Approach for Distributed Cooperative Control of Autonomous Underwater Vehicles

    Lu, Yimeng

    2018-05-01

    This thesis explores a game-theoretical approach for underwater environmental monitoring applications. We first apply game-theoretical algorithm to multi-agent resource coverage problem in drifting environments. Furthermore, existing utility design and learning process of the algorithm are modified to fit specific constraints of underwater exploration/monitoring tasks. The revised approach can take the real scenario of underwater monitoring applications such as the effect of sea current, previous knowledge of the resource and occasional communications between agents into account, and adapt to them to reach better performance. As the motivation of this thesis is from real applications, in this work we emphasize highly on implementation phase. A ROS-Gazebo simulation environment was created for preparation of actual tests. The algorithms are implemented in simulating both the dynamics of vehicles and the environment. After that, a multi-agent underwater autonomous robotic system was developed for hardware test in real settings with local controllers to make their own decisions. These systems are used for testing above mentioned algorithms and future development of other underwater projects. After that, other works related to robotics during this thesis will be briefly mentioned, including contributions in MBZIRC robotics competition and distributed control of UAVs in an adversarial environment.

  11. A study of brain networks associated with swallowing using graph-theoretical approaches.

    Bo Luan

    Full Text Available Functional connectivity between brain regions during swallowing tasks is still not well understood. Understanding these complex interactions is of great interest from both a scientific and a clinical perspective. In this study, functional magnetic resonance imaging (fMRI was utilized to study brain functional networks during voluntary saliva swallowing in twenty-two adult healthy subjects (all females, [Formula: see text] years of age. To construct these functional connections, we computed mean partial correlation matrices over ninety brain regions for each participant. Two regions were determined to be functionally connected if their correlation was above a certain threshold. These correlation matrices were then analyzed using graph-theoretical approaches. In particular, we considered several network measures for the whole brain and for swallowing-related brain regions. The results have shown that significant pairwise functional connections were, mostly, either local and intra-hemispheric or symmetrically inter-hemispheric. Furthermore, we showed that all human brain functional network, although varying in some degree, had typical small-world properties as compared to regular networks and random networks. These properties allow information transfer within the network at a relatively high efficiency. Swallowing-related brain regions also had higher values for some of the network measures in comparison to when these measures were calculated for the whole brain. The current results warrant further investigation of graph-theoretical approaches as a potential tool for understanding the neural basis of dysphagia.

  12. Supply chain collaboration: A Game-theoretic approach to profit allocation

    Ponte, B.; Fernández, I.; Rosillo, R.; Parreño, J.; García, N.

    2016-01-01

    Purpose: This paper aims to develop a theoretical framework for profit allocation, as a mechanism for aligning incentives, in collaborative supply chains. Design/methodology/approach: The issue of profit distribution is approached from a game-theoretic perspective. We use the nucleolus concept. The framework is illustrated through a numerical example based on the Beer Game scenario. Findings: The nucleolus offers a powerful perspective to tackle this problem, as it takes into consideration the bargaining power of the different echelons. We show that this framework outperforms classical alternatives. Research limitations/implications: The allocation of the overall supply chain profit is analyzed from a static perspective. Considering the dynamic nature of the problem would be an interesting next step. Practical implications: We provide evidence of drawbacks derived from classical solutions to the profit allocation problem. Real-world collaborative supply chains need of robust mechanisms like the one tackled in this work to align incentives from the various actors. Originality/value: Adopting an efficient collaborative solution is a major challenge for supply chains, since it is a wide and complex process that requires an appropriate scheme. Within this framework, profit allocation is essential.

  13. Renormalization group approach to Sudakov resummation in prompt photon production

    Bolzoni, Paolo; Forte, Stefano; Ridolfi, Giovanni

    2005-01-01

    We prove the all-order exponentiation of soft logarithmic corrections to prompt photon production in hadronic collisions, by generalizing an approach previously developed in the context of Drell-Yan production and deep-inelastic scattering. We show that all large logs in the soft limit can be expressed in terms of two dimensionful variables, and we use the renormalization group to resum them. The resummed results that we obtain are more general though less predictive than those proposed by other groups, in that they can accommodate for violations of Sudakov factorization

  14. Substituent effects on the relaxation dynamics of furan, furfural and β-furfural: a combined theoretical and experimental approach.

    Oesterling, Sven; Schalk, Oliver; Geng, Ting; Thomas, Richard D; Hansson, Tony; de Vivie-Riedle, Regina

    2017-01-18

    For the series furan, furfural and β-furfural we investigated the effect of substituents and their positioning on the photoinduced relaxation dynamics in a combined theoretical and experimental approach. Using time resolved photoelectron spectroscopy with a high intensity probe pulse, we can, for the first time, follow the whole deactivation process of furan through a two photon probe signal. Using the extended 2-electron 2-orbital model [Nenov et al., J. Chem. Phys., 2011, 135, 034304] we explain the formation of one central conical intersection and predict the influence of the aldehyde group of the derivatives on its geometry. This, as well as the relaxation mechanisms from photoexcitation to the final outcome was investigated using a variety of theoretical methods. Complete active space self consistent field was used for on-the-fly calculations while complete active space perturbation theory and coupled cluster theory were used to accurately describe critical configurations. Experiment and theory show the relaxation dynamics of furfural and β-furfural to be slowed down, and together they disclose an additional deactivation pathway, which is attributed to the n O lonepair state introduced with the aldehyde group.

  15. Group investigation with scientific approach in mathematics learning

    Indarti, D.; Mardiyana; Pramudya, I.

    2018-03-01

    The aim of this research is to find out the effect of learning model toward mathematics achievement. This research is quasi-experimental research. The population of research is all VII grade students of Karanganyar regency in the academic year of 2016/2017. The sample of this research was taken using stratified cluster random sampling technique. Data collection was done based on mathematics achievement test. The data analysis technique used one-way ANOVA following the normality test with liliefors method and homogeneity test with Bartlett method. The results of this research is the mathematics learning using Group Investigation learning model with scientific approach produces the better mathematics learning achievement than learning with conventional model on material of quadrilateral. Group Investigation learning model with scientific approach can be used by the teachers in mathematics learning, especially in the material of quadrilateral, which is can improve the mathematics achievement.

  16. Reference group theory with implications for information studies: a theoretical essay

    E. Murell Dawson

    2001-01-01

    Full Text Available This article explores the role and implications of reference group theory in relation to the field of library and information science. Reference group theory is based upon the principle that people take the standards of significant others as a basis for making self-appraisals, comparisons, and choices regarding need and use of information. Research that applies concepts of reference group theory to various sectors of library and information studies can provide data useful in enhancing areas such as information-seeking research, special populations, and uses of information. Implications are promising that knowledge gained from like research can be beneficial in helping information professionals better understand the role theory plays in examining ways in which people manage their information and social worlds.

  17. An integrated approach to sensor FDI and signal reconstruction in HTGRs – Part I: Theoretical framework

    Uren, Kenneth R.; Schoor, George van; Rand, Carel P. du; Botha, Anrika

    2016-01-01

    Highlights: • An integrated sensor fault detection and isolation method for nuclear power plants. • Utilise techniques such as non-temporal parity space and principal component analysis. • Utilise statistical methods and fuzzy systems for sensor fault isolation. • Allow the detection of multiple sensor faults. • Proposed methodology suitable for online implementation. - Abstract: Sensor fault detection and isolation (FDI) is an important element in modern nuclear power plant (NPP) diagnostic systems. In this respect, sensor FDI of generation II and III water-cooled nuclear energy systems has become an active research topic to continually improve levels of reliability, safety, and operation. However, evolutionary advances in reactor and component technology together with different energy conversion methodologies support the investigation of alternative approaches to sensor FDI. Within this context, the basic aim of this two part series is to propose, implement and evaluate an integrated approach for sensor FDI and signal reconstruction in generation IV nuclear high temperature gas-cooled reactors (HTGRs). In part I of this two part series, the methodology and theoretical background of the integrated sensor FDI and signal reconstruction approach are given. This approach combines techniques such as non-temporal parity space analysis (PSA), principal component analysis (PCA), sensor fusion and fuzzy decision systems to form a more powerful sensor FDI methodology that exploits the strengths of the individual techniques. An illustrative example of the PCA algorithm is given making use of actual data retrieved from a pilot plant called the pebble bed micro model (PBMM). This is a prototype gas turbine power plant based on the first design configuration of the pebble bed modular reactor (PBMR). In part II, the described integrated sensor fault detection approach will be evaluated by means of two case studies. In the first case study the approach will be evaluated

  18. Group-theoretical model of developed turbulence and renormalization of the Navier-Stokes equation.

    Saveliev, V L; Gorokhovski, M A

    2005-07-01

    On the basis of the Euler equation and its symmetry properties, this paper proposes a model of stationary homogeneous developed turbulence. A regularized averaging formula for the product of two fields is obtained. An equation for the averaged turbulent velocity field is derived from the Navier-Stokes equation by renormalization-group transformation.

  19. Developing theory-informed behaviour change interventions to implement evidence into practice: a systematic approach using the Theoretical Domains Framework

    French Simon D

    2012-04-01

    Full Text Available Abstract Background There is little systematic operational guidance about how best to develop complex interventions to reduce the gap between practice and evidence. This article is one in a Series of articles documenting the development and use of the Theoretical Domains Framework (TDF to advance the science of implementation research. Methods The intervention was developed considering three main components: theory, evidence, and practical issues. We used a four-step approach, consisting of guiding questions, to direct the choice of the most appropriate components of an implementation intervention: Who needs to do what, differently? Using a theoretical framework, which barriers and enablers need to be addressed? Which intervention components (behaviour change techniques and mode(s of delivery could overcome the modifiable barriers and enhance the enablers? And how can behaviour change be measured and understood? Results A complex implementation intervention was designed that aimed to improve acute low back pain management in primary care. We used the TDF to identify the barriers and enablers to the uptake of evidence into practice and to guide the choice of intervention components. These components were then combined into a cohesive intervention. The intervention was delivered via two facilitated interactive small group workshops. We also produced a DVD to distribute to all participants in the intervention group. We chose outcome measures in order to assess the mediating mechanisms of behaviour change. Conclusions We have illustrated a four-step systematic method for developing an intervention designed to change clinical practice based on a theoretical framework. The method of development provides a systematic framework that could be used by others developing complex implementation interventions. While this framework should be iteratively adjusted and refined to suit other contexts and settings, we believe that the four-step process should be

  20. Developing theory-informed behaviour change interventions to implement evidence into practice: a systematic approach using the Theoretical Domains Framework.

    French, Simon D; Green, Sally E; O'Connor, Denise A; McKenzie, Joanne E; Francis, Jill J; Michie, Susan; Buchbinder, Rachelle; Schattner, Peter; Spike, Neil; Grimshaw, Jeremy M

    2012-04-24

    There is little systematic operational guidance about how best to develop complex interventions to reduce the gap between practice and evidence. This article is one in a Series of articles documenting the development and use of the Theoretical Domains Framework (TDF) to advance the science of implementation research. The intervention was developed considering three main components: theory, evidence, and practical issues. We used a four-step approach, consisting of guiding questions, to direct the choice of the most appropriate components of an implementation intervention: Who needs to do what, differently? Using a theoretical framework, which barriers and enablers need to be addressed? Which intervention components (behaviour change techniques and mode(s) of delivery) could overcome the modifiable barriers and enhance the enablers? And how can behaviour change be measured and understood? A complex implementation intervention was designed that aimed to improve acute low back pain management in primary care. We used the TDF to identify the barriers and enablers to the uptake of evidence into practice and to guide the choice of intervention components. These components were then combined into a cohesive intervention. The intervention was delivered via two facilitated interactive small group workshops. We also produced a DVD to distribute to all participants in the intervention group. We chose outcome measures in order to assess the mediating mechanisms of behaviour change. We have illustrated a four-step systematic method for developing an intervention designed to change clinical practice based on a theoretical framework. The method of development provides a systematic framework that could be used by others developing complex implementation interventions. While this framework should be iteratively adjusted and refined to suit other contexts and settings, we believe that the four-step process should be maintained as the primary framework to guide researchers through a

  1. Lateral Load Capacity of Piles: A Comparative Study Between Indian Standards and Theoretical Approach

    Jayasree, P. K.; Arun, K. V.; Oormila, R.; Sreelakshmi, H.

    2018-05-01

    As per Indian Standards, laterally loaded piles are usually analysed using the method adopted by IS 2911-2010 (Part 1/Section 2). But the practising engineers are of the opinion that the IS method is very conservative in design. This work aims at determining the extent to which the conventional IS design approach is conservative. This is done through a comparative study between IS approach and the theoretical model based on Vesic's equation. Bore log details for six different bridges were collected from the Kerala Public Works Department. Cast in situ fixed head piles embedded in three soil conditions both end bearing as well as friction piles were considered and analyzed separately. Piles were also modelled in STAAD.Pro software based on IS approach and the results were validated using Matlock and Reese (In Proceedings of fifth international conference on soil mechanics and foundation engineering, 1961) equation. The results were presented as the percentage variation in values of bending moment and deflection obtained by different methods. The results obtained from the mathematical model based on Vesic's equation and that obtained as per the IS approach were compared and the IS method was found to be uneconomical and conservative.

  2. Modeling the economic impact of medication adherence in type 2 diabetes: a theoretical approach.

    Cobden, David S; Niessen, Louis W; Rutten, Frans Fh; Redekop, W Ken

    2010-09-07

    While strong correlations exist between medication adherence and health economic outcomes in type 2 diabetes, current economic analyses do not adequately consider them. We propose a new approach to incorporate adherence in cost-effectiveness analysis. We describe a theoretical approach to incorporating the effect of adherence when estimating the long-term costs and effectiveness of an antidiabetic medication. This approach was applied in a Markov model which includes common diabetic health states. We compared two treatments using hypothetical patient cohorts: injectable insulin (IDM) and oral (OAD) medications. Two analyses were performed, one which ignored adherence (analysis 1) and one which incorporated it (analysis 2). Results from the two analyses were then compared to explore the extent to which adherence may impact incremental cost-effectiveness ratios. In both analyses, IDM was more costly and more effective than OAD. When adherence was ignored, IDM generated an incremental cost-effectiveness of $12,097 per quality-adjusted life-year (QALY) gained versus OAD. Incorporation of adherence resulted in a slightly higher ratio ($16,241/QALY). This increase was primarily due to better adherence with OAD than with IDM, and the higher direct medical costs for IDM. Incorporating medication adherence into economic analyses can meaningfully influence the estimated cost-effectiveness of type 2 diabetes treatments, and should therefore be considered in health care decision-making. Future work on the impact of adherence on health economic outcomes, and validation of different approaches to modeling adherence, is warranted.

  3. Theoretical approach in optimization of stability of the multicomponent solid waste form

    Raicevic, S.; Plecas, I.; Mandic, M.

    1998-01-01

    Chemical precipitation of radionuclides and their immobilization into the solid matrix represents an important approach in the radioactive wastewater treatment. Unfortunately, because of the complexity of the system, optimization of this process in terms of its efficacy and safety represents a serious practical problem, even in treatment of the monocomponent nuclear waste. This situation is additionally complicated in the case of the polycomponent nuclear waste because of the synergic effects of interactions between the radioactive components and the solid matrix. Recently, we have proposed a general theoretical approach for optimization of the process of precipitation and immobilization of metal impurities by the solid matrix. One of the main advantages of this approach represents the possibility of treatment of the multicomponent liquid waste, immobilized by the solid matrix. This approach was used here for investigation of the stability of the system hydroxyapatite (HAP) - Pb/Cd, which was selected as a model multicomponent waste system. In this analysis, we have used a structurally dependent term of the cohesive energy as a stability criterion. (author)

  4. Age groups related glioblastoma study based on radiomics approach.

    Li, Zeju; Wang, Yuanyuan; Yu, Jinhua; Guo, Yi; Zhang, Qi

    2017-12-01

    Glioblastoma is the most aggressive malignant brain tumor with poor prognosis. Radiomics is a newly emerging and promising technique to reveal the complex relationships between high-throughput medical image features and deep information of disease including pathology, biomarkers and genomics. An approach was developed to investigate the internal relationship between magnetic resonance imaging (MRI) features and the age-related origins of glioblastomas based on a quantitative radiomics method. A fully automatic image segmentation method was applied to segment the tumor regions from three dimensional MRI images. 555 features were then extracted from the image data. By analyzing large numbers of quantitative image features, some predictive and prognostic information could be obtained by the radiomics approach. 96 patients diagnosed with glioblastoma pathologically have been divided into two age groups (age groups (T test, p age difference (T test, p= .006). In conclusion, glioblastoma in different age groups present different radiomics-feature patterns with statistical significance, which indicates that glioblastoma in different age groups should have different pathologic, protein, or genic origins.

  5. Wetting transitions: A functional renormalization-group approach

    Fisher, D.S.; Huse, D.A.

    1985-01-01

    A linear functional renormalization group is introduced as a framework in which to treat various wetting transitions of films on substrates. A unified treatment of the wetting transition in three dimensions with short-range interactions is given. The results of Brezin, Halperin, and Leibler in their three different regimes are reproduced along with new results on the multicritical behavior connecting the various regimes. In addition, the critical behavior as the coexistence curve is approached at complete wetting is analyzed. Wetting in the presence of long-range substrate-film interactions that fall off as power laws is also studied. The possible effects of the nonlinear terms in the renormalization group are examined briefly and it appears that they do not alter the critical behavior found using the truncated linear renormalization group

  6. Group Evidential Reasoning Approach for MADA under Fuzziness and Uncertainties

    Mi Zhou

    2013-05-01

    Full Text Available Multiple attribute decision analysis (MADA problems often include both qualitative and quantitative attributes which may be either precise or inaccurate. The evidential reasoning (ER approach is one of reliable and rational methods for dealing with MADA problems and can generate aggregated assessments from a variety of attributes. In many real world decision situations, accurate assessments are difficult to provide such as in group decision situations. Extensive research in dealing with imprecise or uncertain belief structures has been conducted on the basis of the ER approach, such as interval belief degrees, interval weights and interval uncertainty. In this paper, the weights of attributes and utilities of evaluation grades are considered to be fuzzy numbers for the ER approach. Fuzzy analytic hierarchy process (FAHP is used for generating triangular fuzzy weights for attributes from a triangular fuzzy judgment matrix provided by an expert. The weighted arithmetic mean method is proposed to aggregate the triangular fuzzy weights of attributes from a group of experts. -cut is then used to transform the combined triangular fuzzy weights to interval weights for the purpose of dealing with the fuzzy type of weight and utility in a consistent way. Several pairs of group evidential reasoning based nonlinear programming models are then designed to calculate the global fuzzy belief degrees and the overall expected interval utilities of each alternative with interval weights and interval utilities as constraints. A case study is conducted to show the validity and effectiveness of the proposed approach and sensitivity analysis is also conducted on interval weights generated by different -cuts.

  7. Linear mixed-effects modeling approach to FMRI group analysis.

    Chen, Gang; Saad, Ziad S; Britton, Jennifer C; Pine, Daniel S; Cox, Robert W

    2013-06-01

    Conventional group analysis is usually performed with Student-type t-test, regression, or standard AN(C)OVA in which the variance-covariance matrix is presumed to have a simple structure. Some correction approaches are adopted when assumptions about the covariance structure is violated. However, as experiments are designed with different degrees of sophistication, these traditional methods can become cumbersome, or even be unable to handle the situation at hand. For example, most current FMRI software packages have difficulty analyzing the following scenarios at group level: (1) taking within-subject variability into account when there are effect estimates from multiple runs or sessions; (2) continuous explanatory variables (covariates) modeling in the presence of a within-subject (repeated measures) factor, multiple subject-grouping (between-subjects) factors, or the mixture of both; (3) subject-specific adjustments in covariate modeling; (4) group analysis with estimation of hemodynamic response (HDR) function by multiple basis functions; (5) various cases of missing data in longitudinal studies; and (6) group studies involving family members or twins. Here we present a linear mixed-effects modeling (LME) methodology that extends the conventional group analysis approach to analyze many complicated cases, including the six prototypes delineated above, whose analyses would be otherwise either difficult or unfeasible under traditional frameworks such as AN(C)OVA and general linear model (GLM). In addition, the strength of the LME framework lies in its flexibility to model and estimate the variance-covariance structures for both random effects and residuals. The intraclass correlation (ICC) values can be easily obtained with an LME model with crossed random effects, even at the presence of confounding fixed effects. The simulations of one prototypical scenario indicate that the LME modeling keeps a balance between the control for false positives and the sensitivity

  8. Theoretical approaches to maternal-infant interaction: which approach best discriminates between mothers with and without postpartum depression?

    Logsdon, M Cynthia; Mittelberg, Meghan; Morrison, David; Robertson, Ashley; Luther, James F; Wisniewski, Stephen R; Confer, Andrea; Eng, Heather; Sit, Dorothy K Y; Wisner, Katherine L

    2014-12-01

    The purpose of this study was to determine which of the four common approaches to coding maternal-infant interaction best discriminates between mothers with and without postpartum depression. After extensive training, four research assistants coded 83 three minute videotapes of maternal infant interaction at 12month postpartum visits. Four theoretical approaches to coding (Maternal Behavior Q-Sort, the Dyadic Mini Code, Ainsworth Maternal Sensitivity Scale, and the Child-Caregiver Mutual Regulation Scale) were used. Twelve month data were chosen to allow the maximum possible exposure of the infant to maternal depression during the first postpartum year. The videotapes were created in a laboratory with standard procedures. Inter-rater reliabilities for each coding method ranged from .7 to .9. The coders were blind to depression status of the mother. Twenty-seven of the women had major depressive disorder during the 12month postpartum period. Receiver operating characteristics analysis indicated that none of the four methods of analyzing maternal infant interaction discriminated between mothers with and without major depressive disorder. Limitations of the study include the cross-sectional design and the low number of women with major depressive disorder. Further analysis should include data from videotapes at earlier postpartum time periods, and alternative coding approaches should be considered. Nurses should continue to examine culturally appropriate ways in which new mothers can be supported in how to best nurture their babies. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Reflections on the conceptualization and operationalization of a set-theoretic approach to employee motivation and performance research

    James Christopher Ryan

    2017-01-01

    Full Text Available The current commentary offers a reflection on the conceptualizations of Lee and Raschke's (2016 proposal for a set-theoretic approach to employee motivation and organizational performance. The commentary is informed by the current author's operationalization of set-theoretic research on employee motivation which occurred contemporaneously to the work of Lee and Raschke. Observations on the state of current research on employee motivation, development of motivation theory and future directions of set-theoretic approaches to employee motivation and performance are offered.

  10. A short course in quantum information theory. An approach from theoretical physics. 2. ed.

    Diosi, Lajos

    2011-01-01

    This short and concise primer takes the vantage point of theoretical physics and the unity of physics. It sets out to strip the burgeoning field of quantum information science to its basics by linking it to universal concepts in physics. An extensive lecture rather than a comprehensive textbook, this volume is based on courses delivered over several years to advanced undergraduate and beginning graduate students, but essentially it addresses anyone with a working knowledge of basic quantum physics. Readers will find these lectures a most adequate entry point for theoretical studies in this field. For the second edition, the authors has succeeded in adding many new topics while sticking to the conciseness of the overall approach. A new chapter on qubit thermodynamics has been added, while new sections and subsections have been incorporated in various chapter to deal with weak and time-continuous measurements, period-finding quantum algorithms and quantum error corrections. From the reviews of the first edition: ''The best things about this book are its brevity and clarity. In around 100 pages it provides a tutorial introduction to quantum information theory, including problems and solutions.. it's worth a look if you want to quickly get up to speed with the language and central concepts of quantum information theory, including the background classical information theory.'' (Craig Savage, Australian Physics, Vol. 44 (2), 2007). (orig.)

  11. Optimization of rootkit revealing system resources – A game theoretic approach

    K. Muthumanickam

    2015-10-01

    Full Text Available Malicious rootkit is a collection of programs designed with the intent of infecting and monitoring the victim computer without the user’s permission. After the victim has been compromised, the remote attacker can easily cause further damage. In order to infect, compromise and monitor, rootkits adopt Native Application Programming Interface (API hooking technique. To reveal the hidden rootkits, current rootkit detection techniques check different data structures which hold reference to Native APIs. To verify these data structures, a large amount of system resources are required. This is because of the number of APIs in these data structures being quite large. Game theoretic approach is a useful mathematical tool to simulate network attacks. In this paper, a mathematical model is framed to optimize resource consumption using game-theory. To the best of our knowledge, this is the first work to be proposed for optimizing resource consumption while revealing rootkit presence using game theory. Non-cooperative game model is taken to discuss the problem. Analysis and simulation results show that our game theoretic model can effectively reduce the resource consumption by selectively monitoring the number of APIs in windows platform.

  12. A Game Theoretic Approach for Balancing Energy Consumption in Clustered Wireless Sensor Networks.

    Yang, Liu; Lu, Yinzhi; Xiong, Lian; Tao, Yang; Zhong, Yuanchang

    2017-11-17

    Clustering is an effective topology control method in wireless sensor networks (WSNs), since it can enhance the network lifetime and scalability. To prolong the network lifetime in clustered WSNs, an efficient cluster head (CH) optimization policy is essential to distribute the energy among sensor nodes. Recently, game theory has been introduced to model clustering. Each sensor node is considered as a rational and selfish player which will play a clustering game with an equilibrium strategy. Then it decides whether to act as the CH according to this strategy for a tradeoff between providing required services and energy conservation. However, how to get the equilibrium strategy while maximizing the payoff of sensor nodes has rarely been addressed to date. In this paper, we present a game theoretic approach for balancing energy consumption in clustered WSNs. With our novel payoff function, realistic sensor behaviors can be captured well. The energy heterogeneity of nodes is considered by incorporating a penalty mechanism in the payoff function, so the nodes with more energy will compete for CHs more actively. We have obtained the Nash equilibrium (NE) strategy of the clustering game through convex optimization. Specifically, each sensor node can achieve its own maximal payoff when it makes the decision according to this strategy. Through plenty of simulations, our proposed game theoretic clustering is proved to have a good energy balancing performance and consequently the network lifetime is greatly enhanced.

  13. Numerical Methods Application for Reinforced Concrete Elements-Theoretical Approach for Direct Stiffness Matrix Method

    Sergiu Ciprian Catinas

    2015-07-01

    Full Text Available A detailed theoretical and practical investigation of the reinforced concrete elements is due to recent techniques and method that are implemented in the construction market. More over a theoretical study is a demand for a better and faster approach nowadays due to rapid development of the calculus technique. The paper above will present a study for implementing in a static calculus the direct stiffness matrix method in order capable to address phenomena related to different stages of loading, rapid change of cross section area and physical properties. The method is a demand due to the fact that in our days the FEM (Finite Element Method is the only alternative to such a calculus and FEM are considered as expensive methods from the time and calculus resources point of view. The main goal in such a method is to create the moment-curvature diagram in the cross section that is analyzed. The paper above will express some of the most important techniques and new ideas as well in order to create the moment curvature graphic in the cross sections considered.

  14. An information-theoretic approach to motor action decoding with a reconfigurable parallel architecture.

    Craciun, Stefan; Brockmeier, Austin J; George, Alan D; Lam, Herman; Príncipe, José C

    2011-01-01

    Methods for decoding movements from neural spike counts using adaptive filters often rely on minimizing the mean-squared error. However, for non-Gaussian distribution of errors, this approach is not optimal for performance. Therefore, rather than using probabilistic modeling, we propose an alternate non-parametric approach. In order to extract more structure from the input signal (neuronal spike counts) we propose using minimum error entropy (MEE), an information-theoretic approach that minimizes the error entropy as part of an iterative cost function. However, the disadvantage of using MEE as the cost function for adaptive filters is the increase in computational complexity. In this paper we present a comparison between the decoding performance of the analytic Wiener filter and a linear filter trained with MEE, which is then mapped to a parallel architecture in reconfigurable hardware tailored to the computational needs of the MEE filter. We observe considerable speedup from the hardware design. The adaptation of filter weights for the multiple-input, multiple-output linear filters, necessary in motor decoding, is a highly parallelizable algorithm. It can be decomposed into many independent computational blocks with a parallel architecture readily mapped to a field-programmable gate array (FPGA) and scales to large numbers of neurons. By pipelining and parallelizing independent computations in the algorithm, the proposed parallel architecture has sublinear increases in execution time with respect to both window size and filter order.

  15. A Narrative Approach to Both Teaching and Learning About Democracy with Young Children: A Theoretical Exploration

    maila dinia husni rahim

    2016-03-01

    Full Text Available As adults, we often believe that children are only interested with games and children’s ‘stuff’. However research has shown that children do indeed show a greater interest in the world around them, including about politics, elections, and democracy. If we need to teach children about democracy, what are the best methods of teaching democracy to young children? Narrative is considered as an effective medium to convey messages to children and discuss hard subjects. This paper is a theoretical exploration that looks at the narrative approach to teaching and learning about democracy with young children. The researchers has used a literature review to look at why narratives should be used, what narratives should be used and how to use narratives.

  16. Analysing Buyers' and Sellers' Strategic Interactions in Marketplaces: An Evolutionary Game Theoretic Approach

    Vytelingum, Perukrishnen; Cliff, Dave; Jennings, Nicholas R.

    We develop a new model to analyse the strategic behaviour of buyers and sellers in market mechanisms. In particular, we wish to understand how the different strategies they adopt affect their economic efficiency in the market and to understand the impact of these choices on the overall efficiency of the marketplace. To this end, we adopt a two-population evolutionary game theoretic approach, where we consider how the behaviours of both buyers and sellers evolve in marketplaces. In so doing, we address the shortcomings of the previous state-of-the-art analytical model that assumes that buyers and sellers have to adopt the same mixed strategy in the market. Finally, we apply our model in one of the most common market mechanisms, the Continuous Double Auction, and demonstrate how it allows us to provide new insights into the strategic interactions of such trading agents.

  17. A game-theoretical approach for reciprocal security-related prevention investment decisions

    Reniers, Genserik; Soudan, Karel

    2010-01-01

    Every company situated within a chemical cluster faces important security risks from neighbouring companies. Investing in reciprocal security preventive measures is therefore necessary to avoid major accidents. These investments do not, however, provide a direct return on investment for the investor-company and thus plants are hesitative to invest. Moreover, there is likelihood that even if a company has fully invested in reciprocal security prevention, its neighbour has not, and as a result the company can experience a major accident caused by an initial (minor or major) accident that occurred in an adjacent chemical enterprise. In this article we employ a game-theoretic approach to interpret and model behaviour of two neighbouring chemical plants while negotiating and deciding on reciprocal security prevention investments.

  18. The game as strategy for approach to sexuality with adolescents: theoretical-methodological reflections.

    Souza, Vânia de; Gazzinelli, Maria Flávia; Soares, Amanda Nathale; Fernandes, Marconi Moura; Oliveira, Rebeca Nunes Guedes de; Fonseca, Rosa Maria Godoy Serpa da

    2017-04-01

    To describe the Papo Reto [Straight Talk] game and reflect on its theoretical-methodological basis. Analytical study on the process of elaboration of the Papo Reto online game, destined to adolescents aged 15-18 years, with access to the Game between 2014 and 2015. the interactions of 60 adolescents from Belo Horizonte and São Paulo constituted examples of the potentialities of the Game to favor the approach to sexuality with adolescents through simulation of reality, invention and interaction. Based on those potentialities, four thinking categories were discussed: the game as pedagogic device; the game as simulation of realities; the game as device for inventive learning; and the game empowering the interaction. By permitting that the adolescents take risks on new ways, the Game allows them to become creative and active in the production of senses, in the creation of their discourses and in the ways of thinking, feeling and acting in the sexuality field.

  19. Dynamic Load on a Pipe Caused by Acetylene Detonations – Experiments and Theoretical Approaches

    Axel Sperber

    1999-01-01

    Full Text Available The load acting on the wall of a pipe by a detonation, which is travelling through, is not yet well characterized. The main reasons are the limited amount of sufficiently accurate pressure time history data and the requirement of considering the dynamics of the system. Laser vibrometry measurements were performed to determine the dynamic response of the pipe wall on a detonation. Different modelling approaches were used to quantify, theoretically, the radial displacements of the pipe wall. There is good agreement between measured and predicted values of vibration frequencies and the propagation velocities of transverse waves. Discrepancies mainly due to wave propagation effects were found in the amplitudes of the radial velocities. They might be overcome by the use of a dynamic load factor or improved modelling methods.

  20. Combined action of ionizing radiation with another factor: common rules and theoretical approach

    Kim, Jin Kyu; Roh, Changhyun; Komarova, Ludmila N.; Petin, Vladislav G.

    2013-01-01

    Two or more factors can simultaneously make their combined effects on the biological objects. This study has focused on theoretical approach to synergistic interaction due to the combined action of radiation and another factor on cell inactivation. A mathematical model for the synergistic interaction of different environmental agents was suggested for quantitative prediction of irreversibly damaged cells after combined exposures. The model takes into account the synergistic interaction of agents and based on the supposition that additional effective damages responsible for the synergy are irreversible and originated from an interaction of ineffective sub lesions. The experimental results regarding the irreversible component of radiation damage of diploid yeast cells simultaneous exposed to heat with ionizing radiation or UV light are presented. A good agreement of experimental results with model predictions was demonstrated. The importance of the results obtained for the interpretation of the mechanism of synergistic interaction of various environmental factors is discussed. (author)

  1. Enhanced diffusion under alpha self-irradiation in spent nuclear fuel: Theoretical approaches

    Ferry, Cecile; Lovera, Patrick; Poinssot, Christophe; Garcia, Philippe

    2005-01-01

    Various theoretical approaches have been developed in order to estimate the enhanced diffusion coefficient of fission products under alpha self-irradiation in spent nuclear fuel. These simplified models calculate the effects of alpha particles and recoil atoms on mobility of uranium atoms in UO 2 . They lead to a diffusion coefficient which is proportional to the volume alpha activity with a proportionality factor of about 10 -44 (m 5 ). However, the same models applied for fission lead to a radiation-enhanced diffusion coefficient which is approximately two orders of magnitude lower than values reported in literature for U and Pu. Other models are based on an extrapolation of radiation-enhanced diffusion measured either in reactors or under heavy ion bombardment. These models lead to a proportionality factor between the alpha self-irradiation enhanced diffusion coefficient and the volume alpha activity of 2 x 10 -41 (m 5 )

  2. Cross-cultural undergraduate medical education in North America: theoretical concepts and educational approaches.

    Reitmanova, Sylvia

    2011-04-01

    Cross-cultural undergraduate medical education in North America lacks conceptual clarity. Consequently, school curricula are unsystematic, nonuniform, and fragmented. This article provides a literature review about available conceptual models of cross-cultural medical education. The clarification of these models may inform the development of effective educational programs to enable students to provide better quality care to patients from diverse sociocultural backgrounds. The approaches to cross-cultural health education can be organized under the rubric of two specific conceptual models: cultural competence and critical culturalism. The variation in the conception of culture adopted in these two models results in differences in all curricular components: learning outcomes, content, educational strategies, teaching methods, student assessment, and program evaluation. Medical schools could benefit from more theoretical guidance on the learning outcomes, content, and educational strategies provided to them by governing and licensing bodies. More student assessments and program evaluations are needed in order to appraise the effectiveness of cross-cultural undergraduate medical education.

  3. Theoretical approaches to creation of robotic coal mines based on the synthesis of simulation technologies

    Fryanov, V. N.; Pavlova, L. D.; Temlyantsev, M. V.

    2017-09-01

    Methodological approaches to theoretical substantiation of the structure and parameters of robotic coal mines are outlined. The results of mathematical and numerical modeling revealed the features of manifestation of geomechanical and gas dynamic processes in the conditions of robotic mines. Technological solutions for the design and manufacture of technical means for robotic mine are adopted using the method of economic and mathematical modeling and in accordance with the current regulatory documents. For a comparative performance evaluation of technological schemes of traditional and robotic mines, methods of cognitive modeling and matrix search for subsystem elements in the synthesis of a complex geotechnological system are applied. It is substantiated that the process of technical re-equipment of a traditional mine with a phased transition to a robotic mine will reduce unit costs by almost 1.5 times with a significant social effect due to a reduction in the number of personnel engaged in hazardous work.

  4. A Theoretical Analysis of the Mission Statement Based on the Axiological Approach

    Marius-Costel EŞI

    2016-12-01

    Full Text Available The aim of this work is focused on a theoretical analysis of formulating the mission statement of business organizations in relation to the idea of the organizational axiological core. On one hand, we consider the CSR-Corporate Social Responsibility which, in our view, must be brought into direct connection both with the moral entrepreneurship (which should support the philosophical perspective of the statement of business organizations mission and the purely economic entrepreneurship based on profit maximization (which should support the pragmatic perspective. On the other hand, an analysis of the moral concepts which should underpin business is becoming fundamental, in our view, as far as the idea of the social specific value of the social entrepreneurship is evidenced. Therefore, our approach highlights a number of epistemic explanations in relation to the actual practice dimension.

  5. The self-schema model: a theoretical approach to the self-concept in eating disorders.

    Stein, K F

    1996-04-01

    Over the last several decades, the self-concept has been implicated as a important determinant of eating disorders (ED). Although considerable progress has been made, questions remain unanswered about the properties of self-concept that distinguish women with an ED from other populations, and mechanisms that link the self-concept to the disordered behaviors. Markus's self-schema model is presented as a theoretical approach to explore the role of the self-concept in ED. To show how the schema model can be integrated with existing work on the self-concept in ED, a framework is proposed that addresses the number, content, and accessibility of the self-schemas. More specifically, it is posited that a limited collection of positive self-schemas available in memory, in combination with a chronically and inflexibly accessible body-weight self-schema, lead to the disordered behaviors associated with anorexia nervosa and bulimia nervosa.

  6. Combined action of ionizing radiation with another factor: common rules and theoretical approach

    Kim, Jin Kyu; Roh, Changhyun, E-mail: jkkim@kaeri.re.kr [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Komarova, Ludmila N.; Petin, Vladislav G., E-mail: vgpetin@yahoo.com [Medical Radiological Research Center, Obninsk (Russian Federation)

    2013-07-01

    Two or more factors can simultaneously make their combined effects on the biological objects. This study has focused on theoretical approach to synergistic interaction due to the combined action of radiation and another factor on cell inactivation. A mathematical model for the synergistic interaction of different environmental agents was suggested for quantitative prediction of irreversibly damaged cells after combined exposures. The model takes into account the synergistic interaction of agents and based on the supposition that additional effective damages responsible for the synergy are irreversible and originated from an interaction of ineffective sub lesions. The experimental results regarding the irreversible component of radiation damage of diploid yeast cells simultaneous exposed to heat with ionizing radiation or UV light are presented. A good agreement of experimental results with model predictions was demonstrated. The importance of the results obtained for the interpretation of the mechanism of synergistic interaction of various environmental factors is discussed. (author)

  7. Region innovation and investment development: conceptual theoretical approach and business solutions

    Zozulya D.M.

    2017-01-01

    Full Text Available The article describes essential problems of the region business innovation and investment development under current conditions, issues of crisis restrictions negotiation and innovation-driven economy formation. The relevance of the research is defined by the need of effective tools creation for business innovation and investment development and support, which can be applied, first, to increase efficiency of the region industrial activity, then improve production competitiveness on the innovative basis, overcome existing problems and provide sustainable innovation development in the region. The results of conducted research are represented in the article including region innovation and investment development concept model made up by the authors on the basis of system theoretical approach. The tools of the region innovation development defined in the concept model are briefly reviewed in the article. The most important of them include engineering marketing (marketing of scientific and technical innovations, strategic planning, benchmarking, place marketing and business process modeling.

  8. WOMEN, FOOTBALL AND EUROPEAN INTEGRATION. AIMS AND QUESTIONS, METHODOLOGICAL AND THEORETICAL APPROACHES

    Gertrud Pfister

    2013-12-01

    Full Text Available The aim of this article is to introduce a new research topic and provide information about a European research project focusing on football as a means of European integration. Using the results of available studies of the author and other scholars, it is to be discussed whether and how women can participate in football cultures and contribute to a European identity. Based on theoretical approaches to national identity, gender and socialization, as well as and on the analysis of various intersections between gender, football and fandom, it can be concluded that women are still outsiders in the world of football and that it is doubtful whether female players and fans will contribute decisively to Europeanization processes.

  9. A Game-Theoretic Approach to Branching Time Abstract-Check-Refine Process

    Wang, Yi; Tamai, Tetsuo

    2009-01-01

    Since the complexity of software systems continues to grow, most engineers face two serious problems: the state space explosion problem and the problem of how to debug systems. In this paper, we propose a game-theoretic approach to full branching time model checking on three-valued semantics. The three-valued models and logics provide successful abstraction that overcomes the state space explosion problem. The game style model checking that generates counter-examples can guide refinement or identify validated formulas, which solves the system debugging problem. Furthermore, output of our game style method will give significant information to engineers in detecting where errors have occurred and what the causes of the errors are.

  10. An Information-Theoretic Approach for Indirect Train Traffic Monitoring Using Building Vibration

    Susu Xu

    2017-05-01

    Full Text Available This paper introduces an indirect train traffic monitoring method to detect and infer real-time train events based on the vibration response of a nearby building. Monitoring and characterizing traffic events are important for cities to improve the efficiency of transportation systems (e.g., train passing, heavy trucks, and traffic. Most prior work falls into two categories: (1 methods that require intensive labor to manually record events or (2 systems that require deployment of dedicated sensors. These approaches are difficult and costly to execute and maintain. In addition, most prior work uses dedicated sensors designed for a single purpose, resulting in deployment of multiple sensor systems. This further increases costs. Meanwhile, with the increasing demands of structural health monitoring, many vibration sensors are being deployed in commercial buildings. Traffic events create ground vibration that propagates to nearby building structures inducing noisy vibration responses. We present an information-theoretic method for train event monitoring using commonly existing vibration sensors deployed for building health monitoring. The key idea is to represent the wave propagation in a building induced by train traffic as information conveyed in noisy measurement signals. Our technique first uses wavelet analysis to detect train events. Then, by analyzing information exchange patterns of building vibration signals, we infer the category of the events (i.e., southbound or northbound train. Our algorithm is evaluated with an 11-story building where trains pass by frequently. The results show that the method can robustly achieve a train event detection accuracy of up to a 93% true positive rate and an 80% true negative rate. For direction categorization, compared with the traditional signal processing method, our information-theoretic approach reduces categorization error from 32.1 to 12.1%, which is a 2.5× improvement.

  11. Information-Theoretic Approaches for Evaluating Complex Adaptive Social Simulation Systems

    Omitaomu, Olufemi A [ORNL; Ganguly, Auroop R [ORNL; Jiao, Yu [ORNL

    2009-01-01

    In this paper, we propose information-theoretic approaches for comparing and evaluating complex agent-based models. In information theoretic terms, entropy and mutual information are two measures of system complexity. We used entropy as a measure of the regularity of the number of agents in a social class; and mutual information as a measure of information shared by two social classes. Using our approaches, we compared two analogous agent-based (AB) models developed for regional-scale social-simulation system. The first AB model, called ABM-1, is a complex AB built with 10,000 agents on a desktop environment and used aggregate data; the second AB model, ABM-2, was built with 31 million agents on a highperformance computing framework located at Oak Ridge National Laboratory, and fine-resolution data from the LandScan Global Population Database. The initializations were slightly different, with ABM-1 using samples from a probability distribution and ABM-2 using polling data from Gallop for a deterministic initialization. The geographical and temporal domain was present-day Afghanistan, and the end result was the number of agents with one of three behavioral modes (proinsurgent, neutral, and pro-government) corresponding to the population mindshare. The theories embedded in each model were identical, and the test simulations focused on a test of three leadership theories - legitimacy, coercion, and representative, and two social mobilization theories - social influence and repression. The theories are tied together using the Cobb-Douglas utility function. Based on our results, the hypothesis that performance measures can be developed to compare and contrast AB models appears to be supported. Furthermore, we observed significant bias in the two models. Even so, further tests and investigations are required not only with a wider class of theories and AB models, but also with additional observed or simulated data and more comprehensive performance measures.

  12. Theoretical approach to the institutionalization of forms of governance resource provision of innovative activity

    M. S. Asmolova

    2016-01-01

    Full Text Available Knowledge economy research due to the actualization of the role of knowledge and information. Management, its impact and the institutionalization of management resource provision designed to overcome the problems inherent in the present stage of development. An important research direction is to carry out theoretical analysis of economic resources in the context of their occurrence, development and improvement. This assertion has identified the need to consider the theoretical approach to the institutionalization of forms of resource management software innovation and analysis and typology of approaches by different parameters on the basis of analysis of a large number of sources. The features of the concept of institutionalization as defined phenomenon in a time perspective. In an analysis conducted by scientists used studies from different periods in the development of economic science. The analysis of numerous professional and scientific research led to the conclusion that knowledge and information should be dis-regarded as a new type of economic production factors. Separately, analyzed the impact of globalization processes that have affected the scientific and innovative sphere. Allocated to a separate study by side issues of innovative development of the Russian economy, which prevents the unresolved improve the competitiveness of the national economic and inhibits the formation of regional and national innovation system, restraining the transition to an innovative model of development. Citing as evidence of the deepening of economic globalization, the role of new information technologies and the formation of a single information space. Noting the fact that if the earlier science developed to deepen knowledge on the basis of the social division of Sciences, in the coming century should happen deepening of knowledge on the basis of their socialization.

  13. Choosing Appropriate Theories for Understanding Hospital Reporting of Adverse Drug Events, a Theoretical Domains Framework Approach.

    Shalviri, Gloria; Yazdizadeh, Bahareh; Mirbaha, Fariba; Gholami, Kheirollah; Majdzadeh, Reza

    2018-01-01

    Adverse drug events (ADEs) may cause serious injuries including death. Spontaneous reporting of ADEs plays a great role in detection and prevention of them; however, underreporting always exists. Although several interventions have been utilized to solve this problem, they are mainly based on experience and the rationale for choosing them has no theoretical base. The vast variety of behavioural theories makes it difficult to choose appropriate theory. Theoretical domains framework (TDF) is suggested as a solution. The objective of this study was to select the best theory for evaluating ADE reporting in hospitals based on TDF. We carried out three focus group discussions with hospital pharmacists and nurses, based on TDF questions. The analysis was performed through five steps including coding discussions transcript, extracting beliefs, selecting relevant domains, matching related constructs to the extracted beliefs, and determining the appropriate theories in each domain. The theory with the highest number of matched domains and constructs was selected as the theory of choice. A total of six domains were identified relevant to ADE reporting, including "Knowledge", "Skills", "Beliefs about consequences", "Motivation and goals", "Environmental context and resources" and "Social influences". We found theory of planned behavior as the comprehensive theory to study factors influencing ADE reporting in hospitals, since it was relevant theory in five out of six relevant domains and the common theory in 55 out of 75 identified beliefs. In conclusion, we suggest theory of planned behavior for further studies on designing appropriate interventions to increase ADE reporting in hospitals.

  14. New aspects of the antioxidant properties of phenolic acids: a combined theoretical and experimental approach.

    Anouar, E; Kosinová, P; Kozlowski, D; Mokrini, R; Duroux, J L; Trouillas, P

    2009-09-21

    Ferulic acid is widely distributed in the leaves and seeds of cereals as well as in coffee, apples, artichokes, peanuts, oranges and pineapples. Like numerous other natural polyphenols it exhibits antioxidant properties. It is known to act as a free radical scavenger by H atom transfer from the phenolic OH group. In the present joint experimental and theoretical studies we studied a new mechanism to explain such activities. Ferulic acid can indeed act by radical addition on the alpha,beta-double bond. On the basis of the identification of metabolites formed in an oxidative radiolytic solution and after DFT calculations, we studied the thermodynamic and kinetic aspects of this reaction. Addition and HAT reactions were treated as competitive reactions. The possibility of dimer formation was also investigated from a theoretical point of view; the high barriers we obtained contribute to explaining why we did not observe those compounds as major radiolytic compounds. The DPPH free radical scavenging capacity of ferulic acid and the oxidative products was measured and is discussed on the basis of DFT calculations (BDEs and spin densities).

  15. Quantum renormalization group approach to geometric phases in spin chains

    Jafari, R.

    2013-01-01

    A relation between geometric phases and criticality of spin chains are studied using the quantum renormalization-group approach. I have shown how the geometric phase evolve as the size of the system becomes large, i.e., the finite size scaling is obtained. The renormalization scheme demonstrates how the first derivative of the geometric phase with respect to the field strength diverges at the critical point and maximum value of the first derivative, and its position, scales with the exponent of the system size

  16. Potts ferromagnet correlation length in hypercubic lattices: Renormalization - group approach

    Curado, E.M.F.; Hauser, P.R.

    1984-01-01

    Through a real space renormalization group approach, the q-state Potts ferromagnet correlation length on hierarchical lattices is calculated. These hierarchical lattices are build in order to simulate hypercubic lattices. The high-and-low temperature correlation length asymptotic behaviours tend (in the Ising case) to the Bravais lattice correlation length ones when the size of the hierarchical lattice cells tends to infinity. It is conjectured that the asymptotic behaviours several values of q and d (dimensionality) so obtained are correct. Numerical results are obtained for the full temperature range of the correlation length. (Author) [pt

  17. Group-theoretical and topological analysis of localized rotation-vibration states

    Sadovskii, D.A.; Zhilinskii, B.I.

    1993-01-01

    A general scheme of qualitative analysis is applied to molecular rovibrational problems. The classical-quantum correspondence provides a description of different classes of localized quantum rotation-vibration states associated with localized classical motion. A description of qualitative features, such as localized motion, and of qualitative changes, such as localization phenomena, is based on the concept of the simplest Hamiltonian. It uses only the topological properties of the compact reduced phase space and the action of the symmetry group on this space. The qualitative changes of the simplest Hamiltonian are analyzed as bifurcations caused by rotational or vibrational excitation. The relation between the stationary points of the classical Hamiltonian function on the reduced phase space and the principal periodic trajectories in the coordinate space is analyzed for vibrational Hamiltonians. In particular, the relation between the nonlinear normal modes, proposed by Montaldi, Roberts, and Stewart [Philos. Trans. R. Soc. London, Ser. A 325, 237 (1988)], and normal- and local-mode models widely used in molecular physics is discussed. Along with a general consideration of localized rotational and vibrational states a more detailed analysis of the vibrational dynamics of an X 3 molecule with the D 3h symmetry, such as the H 3 + molecular ion, is given

  18. Group theoretical classification of broken symmetry states of the two-fold degenerate Hubbard model on a triangular lattice

    Masago, Akira; Suzuki, Naoshi

    2001-01-01

    By a group theoretical procedure we derive the possible spontaneously broken-symmetry states for the two-fold degenerate Hubbard model on a two-dimensional triangular lattice. For ordering wave vectors corresponding to the points Γ and K in the first BZ we find 22 states which include 16 collinear and six non-collinear states. The collinear states include the usual SDW and CDW states which appear also in the single-band Hubbard model. The non-collinear states include exotic ordering states of orbitals and spins as well as the triangular arrangement of spins

  19. Modeling the economic impact of medication adherence in type 2 diabetes: a theoretical approach

    David S Cobden

    2010-08-01

    Full Text Available David S Cobden1, Louis W Niessen2, Frans FH Rutten1, W Ken Redekop11Department of Health Policy and Management, Section of Health Economics – Medical Technology Assessment (HE-MTA, Erasmus MC, Erasmus University Rotterdam, The Netherlands; 2Department of International Health, Johns Hopkins University School of Public Health, Johns Hopkins Medical Institutions, Baltimore, MD, USAAims: While strong correlations exist between medication adherence and health economic outcomes in type 2 diabetes, current economic analyses do not adequately consider them. We propose a new approach to incorporate adherence in cost-effectiveness analysis.Methods: We describe a theoretical approach to incorporating the effect of adherence when estimating the long-term costs and effectiveness of an antidiabetic medication. This approach was applied in a Markov model which includes common diabetic health states. We compared two treatments using hypothetical patient cohorts: injectable insulin (IDM and oral (OAD medications. Two analyses were performed, one which ignored adherence (analysis 1 and one which incorporated it (analysis 2. Results from the two analyses were then compared to explore the extent to which adherence may impact incremental cost-effectiveness ratios.Results: In both analyses, IDM was more costly and more effective than OAD. When adherence was ignored, IDM generated an incremental cost-effectiveness of $12,097 per quality-adjusted life-year (QALY gained versus OAD. Incorporation of adherence resulted in a slightly higher ratio ($16,241/QALY. This increase was primarily due to better adherence with OAD than with IDM, and the higher direct medical costs for IDM.Conclusions: Incorporating medication adherence into economic analyses can meaningfully influence the estimated cost-effectiveness of type 2 diabetes treatments, and should therefore be ­considered in health care decision-making. Future work on the impact of adherence on health

  20. Resource Allocation for Multicell Device-to-Device Communications in Cellular Network: A Game Theoretic Approach

    Jun Huang

    2015-08-01

    Full Text Available Device-to-Device (D2D communication has recently emerged as a promising technology to improve the capacity and coverage of cellular systems. To successfully implement D2D communications underlaying a cellular network, resource allocation for D2D links plays a critical role. While most of prior resource allocation mechanisms for D2D communications have focused on interference within a single-cell system, this paper investigates the resource allocation problem for a multicell cellular network in which a D2D link reuses available spectrum resources of multiple cells. A repeated game theoretic approach is proposed to address the problem. In this game, the base stations (BSs act as players that compete for resource supply of D2D, and the utility of each player is formulated as revenue collected from both cellular and D2D users using resources. Extensive simulations are conducted to verify the proposed approach and the results show that it can considerably enhance the system performance in terms of sum rate and sum rate gain.

  1. Molecular acidity: An accurate description with information-theoretic approach in density functional reactivity theory.

    Cao, Xiaofang; Rong, Chunying; Zhong, Aiguo; Lu, Tian; Liu, Shubin

    2018-01-15

    Molecular acidity is one of the important physiochemical properties of a molecular system, yet its accurate calculation and prediction are still an unresolved problem in the literature. In this work, we propose to make use of the quantities from the information-theoretic (IT) approach in density functional reactivity theory and provide an accurate description of molecular acidity from a completely new perspective. To illustrate our point, five different categories of acidic series, singly and doubly substituted benzoic acids, singly substituted benzenesulfinic acids, benzeneseleninic acids, phenols, and alkyl carboxylic acids, have been thoroughly examined. We show that using IT quantities such as Shannon entropy, Fisher information, Ghosh-Berkowitz-Parr entropy, information gain, Onicescu information energy, and relative Rényi entropy, one is able to simultaneously predict experimental pKa values of these different categories of compounds. Because of the universality of the quantities employed in this work, which are all density dependent, our approach should be general and be applicable to other systems as well. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  2. Game Theoretic Approach for Systematic Feature Selection; Application in False Alarm Detection in Intensive Care Units

    Fatemeh Afghah

    2018-03-01

    Full Text Available Intensive Care Units (ICUs are equipped with many sophisticated sensors and monitoring devices to provide the highest quality of care for critically ill patients. However, these devices might generate false alarms that reduce standard of care and result in desensitization of caregivers to alarms. Therefore, reducing the number of false alarms is of great importance. Many approaches such as signal processing and machine learning, and designing more accurate sensors have been developed for this purpose. However, the significant intrinsic correlation among the extracted features from different sensors has been mostly overlooked. A majority of current data mining techniques fail to capture such correlation among the collected signals from different sensors that limits their alarm recognition capabilities. Here, we propose a novel information-theoretic predictive modeling technique based on the idea of coalition game theory to enhance the accuracy of false alarm detection in ICUs by accounting for the synergistic power of signal attributes in the feature selection stage. This approach brings together techniques from information theory and game theory to account for inter-features mutual information in determining the most correlated predictors with respect to false alarm by calculating Banzhaf power of each feature. The numerical results show that the proposed method can enhance classification accuracy and improve the area under the ROC (receiver operating characteristic curve compared to other feature selection techniques, when integrated in classifiers such as Bayes-Net that consider inter-features dependencies.

  3. A Theoretical Approach to Understanding Population Dynamics with Seasonal Developmental Durations

    Lou, Yijun; Zhao, Xiao-Qiang

    2017-04-01

    There is a growing body of biological investigations to understand impacts of seasonally changing environmental conditions on population dynamics in various research fields such as single population growth and disease transmission. On the other side, understanding the population dynamics subject to seasonally changing weather conditions plays a fundamental role in predicting the trends of population patterns and disease transmission risks under the scenarios of climate change. With the host-macroparasite interaction as a motivating example, we propose a synthesized approach for investigating the population dynamics subject to seasonal environmental variations from theoretical point of view, where the model development, basic reproduction ratio formulation and computation, and rigorous mathematical analysis are involved. The resultant model with periodic delay presents a novel term related to the rate of change of the developmental duration, bringing new challenges to dynamics analysis. By investigating a periodic semiflow on a suitably chosen phase space, the global dynamics of a threshold type is established: all solutions either go to zero when basic reproduction ratio is less than one, or stabilize at a positive periodic state when the reproduction ratio is greater than one. The synthesized approach developed here is applicable to broader contexts of investigating biological systems with seasonal developmental durations.

  4. Developing TheoreticalMethodological Approaches to Assessment of Export Potential of Ukrainian Enterprises

    Matyushenko Igor Yu.

    2016-02-01

    Full Text Available The article is aimed at studying the existing theoretical-methodological approaches to the analysis and assessment of export potential. The opinions by scientists regarding the disclosure of the categorial content of the concept of «export potential» have been considered, an own definition of the indicated economic category has been suggested. The main types of analytical procedures for assessment have been classified, some authorial methodical approaches to determine the level of export potential have been analyzed. The export potential of a hypothetical enterprise has been calculated by the selected methodologies of assessment. The urgency of improving and refining existing methods to implement more detailed and quantitative analysis has been substantiated. It has been suggested to implement a prognosis assessment of export potential of enterprises by combining the results of several methodologies in the aggregate indicator of export potential efficiency. A prognosis model for the dynamics of export potential of a hypothetical enterprise has been built, value of the aggregate indicator has been calculated on the basis of three selected valuation methodologies.

  5. The strong coupling constant: its theoretical derivation from a geometric approach to hadron structure

    Recami, E.; Tonin-Zanchin, V.

    1991-01-01

    Since more than a decade, a bi-scale, unified approach to strong and gravitational interactions has been proposed, that uses the geometrical methods of general relativity, and yielded results similar to strong gravity theory's. We fix our attention, in this note, on hadron structure, and show that also the strong interaction strength α s, ordinarily called the (perturbative) coupling-constant square, can be evaluated within our theory, and found to decrease (increase) as the distance r decreases (increases). This yields both the confinement of the hadron constituents for large values of r, and their asymptotic freedom [for small values of r inside the hadron]: in qualitative agreement with the experimental evidence. In other words, our approach leads us, on a purely theoretical ground, to a dependence of α s on r which had been previously found only on phenomenological and heuristical grounds. We expect the above agreement to be also quantitative, on the basis of a few checks performed in this paper, and of further work of ours about calculating meson mass-spectra. (author)

  6. Cartography, new technologies and geographic education: theoretical approaches to research the field

    Seneme do Canto, Tânia

    2018-05-01

    In order to understand the roles that digital mapping can play in cartographic and geographic education, this paper discusses the theoretical and methodological approach used in a research that is undertaking in the education of geography teachers. To develop the study, we found in the works of Lankshear and Knobel (2013) a notion of new literacies that allows us looking at the practices within digital mapping in a sociocultural perspective. From them, we conclude that in order to understand the changes that digital cartography is able to foment in geography teaching, it is necessary to go beyond the substitution of means in the classroom and being able to explore what makes the new mapping practices different from others already consolidated in geography teaching. Therefore, we comment on some features of new forms of cartographic literacy that are in full development with digital technologies, but which are not determined solely by their use. The ideas of Kitchin and Dodge (2007) and Del Casino Junior and Hanna (2006) are also an important reference for the research. Methodologically, this approach helps us to understand that in the seek to comprehend maps and their meanings, irrespective of the medium used, we are dealing with a process of literacy that is very particular and emergent because it involves not only the characteristics of the map artifact and of the individual that produces or consumes it, but depends mainly on a diversity of interconnections that are being built between them (map and individual) and the world.

  7. The prediction of candidate genes for cervix related cancer through gene ontology and graph theoretical approach.

    Hindumathi, V; Kranthi, T; Rao, S B; Manimaran, P

    2014-06-01

    With rapidly changing technology, prediction of candidate genes has become an indispensable task in recent years mainly in the field of biological research. The empirical methods for candidate gene prioritization that succors to explore the potential pathway between genetic determinants and complex diseases are highly cumbersome and labor intensive. In such a scenario predicting potential targets for a disease state through in silico approaches are of researcher's interest. The prodigious availability of protein interaction data coupled with gene annotation renders an ease in the accurate determination of disease specific candidate genes. In our work we have prioritized the cervix related cancer candidate genes by employing Csaba Ortutay and his co-workers approach of identifying the candidate genes through graph theoretical centrality measures and gene ontology. With the advantage of the human protein interaction data, cervical cancer gene sets and the ontological terms, we were able to predict 15 novel candidates for cervical carcinogenesis. The disease relevance of the anticipated candidate genes was corroborated through a literature survey. Also the presence of the drugs for these candidates was detected through Therapeutic Target Database (TTD) and DrugMap Central (DMC) which affirms that they may be endowed as potential drug targets for cervical cancer.

  8. An effectiveness analysis of healthcare systems using a systems theoretic approach

    Inder Kerry

    2009-10-01

    surveyors is developed that provides a systematic search for improving the impact of accreditation on quality of care and hence on the accreditation/performance correlation. Conclusion There is clear value in developing a theoretical systems approach to achieving quality in health care. The introduction of the systematic surveyor-based search for improvements creates an adaptive-control system to optimize health care quality. It is hoped that these outcomes will stimulate further research in the development of strategic planning using systems theoretic approach for the improvement of quality in health care.

  9. An effectiveness analysis of healthcare systems using a systems theoretic approach.

    Chuang, Sheuwen; Inder, Kerry

    2009-10-24

    improving the impact of accreditation on quality of care and hence on the accreditation/performance correlation. There is clear value in developing a theoretical systems approach to achieving quality in health care. The introduction of the systematic surveyor-based search for improvements creates an adaptive-control system to optimize health care quality. It is hoped that these outcomes will stimulate further research in the development of strategic planning using systems theoretic approach for the improvement of quality in health care.

  10. Beyond the Cognitive and the Virtue Approaches to Moral Education: Some Theoretical Foundations for an Integrated Account of Moral Education.

    Roh, Young-Ran

    2000-01-01

    Explores theoretical foundation for integrated approach to moral education; discusses rational choice and moral action within human reflective structure; investigates moral values required for integrative approach to moral education; discusses content of moral motivation, including role of emotion and reason. (Contains 15 references.) (PKP)

  11. Group theoretical treatment of the low-temperature phase transition of the Cd6Ca 1/1-cubic approximant

    Tamura, R.; Shibata, K.; Nishimoto, K.; Takeuchi, S.; Edagawa, K.; Saitoh, K.; Isobe, M.; Ueda, Y.

    2005-01-01

    An antiparallel orientational transition is reported for an intermetallic compound, i.e., Cd 6 Ca crystal, which is a 1/1-1/1-1/1 crystalline approximant to the icosahedral quasicrystal Cd 5.7 Ca. A group theoretical analysis based on the Landau theory predicts that the space group of the low-temperature phase is either C2/c or C2/m, in good agreement with the observations. Accordingly, two types of orientational orderings of Cd 4 tetrahedra, which are located in the center of icosahedral clusters, may occur below 100 K: In both cases, the Cd 4 tetrahedra are orientationally ordered in an antiparallel fashion along the [110] direction of the high temperature body-centered-cubic phase. Such a transition in a metal is reminiscent of orientational transitions in molecular solids

  12. Group theoretical and Hamiltonian structures of integrable evolution equations in 1x1 and 2x1 dimensions

    Konopel'chenko, B.G.

    1983-01-01

    New results in investigation of the group-theoretical and hamiltonian structure of the integrable evolution equations in 1+1 and 2+1 dimensions are briefly reviewed. Main general results, such as the form of integrable equations, Baecklund transfomations, symmetry groups, are turned out to have the same form for different spectral problems. The used generalized AKNS-method (the Ablowitz Kaup, Newell and Segur method) permits to prove that all nonlinear evolution equations considered are hamiltonians. The general condition of effective application of the ACNS mehtod to the concrete spectral problem is the possibility to calculate a recursion operator explicitly. The embedded representation is shown to be a fundamental object connected with different aspects of the inverse scattering problem

  13. Theoretical and numerical investigations of TAP experiments. New approaches for variable pressure conditions

    Senechal, U.; Breitkopf, C. [Technische Univ. Dresden (Germany). Inst. fuer Energietechnik

    2011-07-01

    Temporal analysis of products (TAP) is a valuable tool for characterization of porous catalytic structures. Established TAP-modeling requires a spatially constant diffusion coefficient and neglect convective flows, which is only valid in Knudsen diffusion regime. Therefore in experiments, the number of molecules per pulse must be chosen accordingly. New approaches for variable process conditions are highly required. Thus, a new theoretical model is developed for estimating the number of molecules per pulse to meet these requirements under any conditions and at any time. The void volume is calculated as the biggest sphere fitting between three pellets. The total number of pulsed molecules is assumed to fill the first void volume at the inlet immediately. Molecule numbers from these calculations can be understood as maximum possible molecules at any time in the reactor to be in Knudsen diffusion regime, i.e., above the Knudsen number of 2. Moreover, a new methodology for generating a full three-dimensional geometrical representation of beds is presented and used for numerical simulations to investigate spatial effects. Based on a freely available open-source game physics engine library (BULLET), beds of arbitrary-sized pellets can be generated and transformed to CFD-usable geometry. In CFD-software (ANSYS CFX registered) a transient diffusive transport equation with time-dependent inlet boundary conditions is solved. Three different pellet diameters were investigated with 1e18 molecules per pulse, which is higher than the limit from the theoretical calculation. Spatial and temporal distributions of transported species show regions inside the reactor, where non-Knudsen conditions exist. From this results, the distance from inlet can be calculated where the theoretical pressure limit (Knudsen number equals 2) is obtained, i.e., from this point to the end of the reactor Knudsen regime can be assumed. Due to linear dependency of pressure and concentration (assuming ideal

  14. PREFACE: The Second International Conference on Inverse Problems: Recent Theoretical Developments and Numerical Approaches

    Cheng, Jin; Hon, Yiu-Chung; Seo, Jin Keun; Yamamoto, Masahiro

    2005-01-01

    The Second International Conference on Inverse Problems: Recent Theoretical Developments and Numerical Approaches was held at Fudan University, Shanghai from 16-21 June 2004. The first conference in this series was held at the City University of Hong Kong in January 2002 and it was agreed to hold the conference once every two years in a Pan-Pacific Asian country. The next conference is scheduled to be held at Hokkaido University, Sapporo, Japan in July 2006. The purpose of this series of biennial conferences is to establish and develop constant international collaboration, especially among the Pan-Pacific Asian countries. In recent decades, interest in inverse problems has been flourishing all over the globe because of both the theoretical interest and practical requirements. In particular, in Asian countries, one is witnessing remarkable new trends of research in inverse problems as well as the participation of many young talents. Considering these trends, the second conference was organized with the chairperson Professor Li Tat-tsien (Fudan University), in order to provide forums for developing research cooperation and to promote activities in the field of inverse problems. Because solutions to inverse problems are needed in various applied fields, we entertained a total of 92 participants at the second conference and arranged various talks which ranged from mathematical analyses to solutions of concrete inverse problems in the real world. This volume contains 18 selected papers, all of which have undergone peer review. The 18 papers are classified as follows: Surveys: four papers give reviews of specific inverse problems. Theoretical aspects: six papers investigate the uniqueness, stability, and reconstruction schemes. Numerical methods: four papers devise new numerical methods and their applications to inverse problems. Solutions to applied inverse problems: four papers discuss concrete inverse problems such as scattering problems and inverse problems in

  15. An information-theoretic approach to assess practical identifiability of parametric dynamical systems.

    Pant, Sanjay; Lombardi, Damiano

    2015-10-01

    A new approach for assessing parameter identifiability of dynamical systems in a Bayesian setting is presented. The concept of Shannon entropy is employed to measure the inherent uncertainty in the parameters. The expected reduction in this uncertainty is seen as the amount of information one expects to gain about the parameters due to the availability of noisy measurements of the dynamical system. Such expected information gain is interpreted in terms of the variance of a hypothetical measurement device that can measure the parameters directly, and is related to practical identifiability of the parameters. If the individual parameters are unidentifiable, correlation between parameter combinations is assessed through conditional mutual information to determine which sets of parameters can be identified together. The information theoretic quantities of entropy and information are evaluated numerically through a combination of Monte Carlo and k-nearest neighbour methods in a non-parametric fashion. Unlike many methods to evaluate identifiability proposed in the literature, the proposed approach takes the measurement-noise into account and is not restricted to any particular noise-structure. Whilst computationally intensive for large dynamical systems, it is easily parallelisable and is non-intrusive as it does not necessitate re-writing of the numerical solvers of the dynamical system. The application of such an approach is presented for a variety of dynamical systems--ranging from systems governed by ordinary differential equations to partial differential equations--and, where possible, validated against results previously published in the literature. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. THEORETICAL APPROACHES TO THE DEFINITION OF MOTIVATION OF PROFESSIONAL ACTIVITY OF PUBLIC SERVANTS

    E. V. Vashalomidze

    2016-01-01

    Full Text Available The relevance of the topic chosen due to the presence of performance motivation development problems of civil servants, including their motivation for continuous professional development, as one of the main directions of development of the civil service in general, approved by the relevant Presidential Decree on 2016–2018 years. In the first part of this article provides a brief analytical overview and an assessment of content and process of theoretical and methodological approaches to solving the problems of motivation of the personnel of socio-economic systems. In the second part of the article on the basis of the research proposed motivating factors in the development of the approaches set out in the first part of the article.The purpose / goal. The aim of the article is to provide methodological assistance to academic institutions involved in the solution of scientific and practical problems of motivation of civil servants to the continuous professional development in accordance with the Presidential Decree of 11 August 2016 № 408.Methodology. The methodological basis of this article are: a comprehensive analysis of normative legal provision of state of the Russian Federation; systematic approach and historical analysis of the theory and methodology of solving problems of staff motivation; method of expert evaluations; the scientific method of analogies.Conclusions / relevance. The practical significance of the article is in the operational delivery of the scientific and methodological assistance to the implementation of the Russian Federation "On the main directions of the state civil service of the Russian Federation in the years 2016–2018" Presidential Decree of 11 August number 403 regarding the establishment of mechanisms to motivate civil servants to continuous professional development.

  17. Theory of transformation groups I general properties of continuous transformation groups a contemporary approach and translation

    2015-01-01

    This modern translation of Sophus Lie's and Friedrich Engel's “Theorie der Transformationsgruppen Band I” will allow readers to discover the striking conceptual clarity and remarkably systematic organizational thought of the original German text. Volume I presents a comprehensive introduction to the theory and is mainly directed towards the generalization of ideas drawn from the study of examples. The major part of the present volume offers an extremely clear translation of the lucid original. The first four chapters provide not only a translation, but also a contemporary approach, which will help present day readers to familiarize themselves with the concepts at the heart of the subject. The editor's main objective was to encourage a renewed interest in the detailed classification of Lie algebras in dimensions 1, 2 and 3, and to offer access to Sophus Lie's monumental Galois theory of continuous transformation groups, established at the end of the 19th Century. Lie groups are widespread in mathematics, p...

  18. Impaired cerebral blood flow networks in temporal lobe epilepsy with hippocampal sclerosis: A graph theoretical approach.

    Sone, Daichi; Matsuda, Hiroshi; Ota, Miho; Maikusa, Norihide; Kimura, Yukio; Sumida, Kaoru; Yokoyama, Kota; Imabayashi, Etsuko; Watanabe, Masako; Watanabe, Yutaka; Okazaki, Mitsutoshi; Sato, Noriko

    2016-09-01

    Graph theory is an emerging method to investigate brain networks. Altered cerebral blood flow (CBF) has frequently been reported in temporal lobe epilepsy (TLE), but graph theoretical findings of CBF are poorly understood. Here, we explored graph theoretical networks of CBF in TLE using arterial spin labeling imaging. We recruited patients with TLE and unilateral hippocampal sclerosis (HS) (19 patients with left TLE, and 21 with right TLE) and 20 gender- and age-matched healthy control subjects. We obtained all participants' CBF maps using pseudo-continuous arterial spin labeling and analyzed them using the Graph Analysis Toolbox (GAT) software program. As a result, compared to the controls, the patients with left TLE showed a significantly low clustering coefficient (p=0.024), local efficiency (p=0.001), global efficiency (p=0.010), and high transitivity (p=0.015), whereas the patients with right TLE showed significantly high assortativity (p=0.046) and transitivity (p=0.011). The group with right TLE also had high characteristic path length values (p=0.085), low global efficiency (p=0.078), and low resilience to targeted attack (p=0.101) at a trend level. Lower normalized clustering coefficient (p=0.081) in the left TLE and higher normalized characteristic path length (p=0.089) in the right TLE were found also at a trend level. Both the patients with left and right TLE showed significantly decreased clustering in similar areas, i.e., the cingulate gyri, precuneus, and occipital lobe. Our findings revealed differing left-right network metrics in which an inefficient CBF network in left TLE and vulnerability to irritation in right TLE are suggested. The left-right common finding of regional decreased clustering might reflect impaired default-mode networks in TLE. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Strategy for a Rock Mechanics Site Descriptive Model. Development and testing of the theoretical approach

    Staub, Isabelle; Fredriksson, Anders; Outters, Nils [Golder Associates AB, Uppsala (Sweden)

    2002-05-01

    In the purpose of studying the possibilities of a Deep Repository for spent fuel, the Swedish Nuclear and Fuel Management Company (SKB) is currently planning for Site Investigations. Data collected from these Site Investigations are interpreted and analysed to achieve the full Site Description, which is built up of models from all the disciplines that are considered of importance for the Site Description. One of these models is the Rock Mechanical Descriptive Model,which would be developed for any site in hard crystalline rock, and is a combination and evaluation of the characterisation of rock mass by means of empirical relationships and a theoretical approach based on numerical modelling. The present report describes the theoretical approach. The characterisation of the mechanical properties of the rock mass, viewed as a unit consisting of intact rock and fractures, is achieved by numerical simulations with following input parameters: initial stresses, fracture geometry, distribution of rock mechanical properties, such as deformation and strength parameters, for the intact rock and for the fractures. The numerical modelling was performed with the two-dimensional code UDEC, and the rock block models were generated from 2D trace sections extracted from the 3D Discrete Fracture Network (DFN) model. Assumptions and uncertainties related to the set-up of the model are considered. The numerical model was set-up to simulate a plain strain-loading test. Different boundary conditions were applied on the model for simulating stress conditions (I) in the undisturbed rock mass, and (II) at the proximity of a tunnel. In order to assess the reliability of the model sensitivity analyses have been conducted on some rock block models for defining the dependency of mechanical properties to in situ stresses, the influence of boundary conditions, rock material and joint constitutive models used to simulate the behaviour of intact rock and fractures, domain size and anisotropy. To

  20. Strategy for a Rock Mechanics Site Descriptive Model. Development and testing of the theoretical approach

    Staub, Isabelle; Fredriksson, Anders; Outters, Nils

    2002-05-01

    In the purpose of studying the possibilities of a Deep Repository for spent fuel, the Swedish Nuclear and Fuel Management Company (SKB) is currently planning for Site Investigations. Data collected from these Site Investigations are interpreted and analysed to achieve the full Site Description, which is built up of models from all the disciplines that are considered of importance for the Site Description. One of these models is the Rock Mechanical Descriptive Model,which would be developed for any site in hard crystalline rock, and is a combination and evaluation of the characterisation of rock mass by means of empirical relationships and a theoretical approach based on numerical modelling. The present report describes the theoretical approach. The characterisation of the mechanical properties of the rock mass, viewed as a unit consisting of intact rock and fractures, is achieved by numerical simulations with following input parameters: initial stresses, fracture geometry, distribution of rock mechanical properties, such as deformation and strength parameters, for the intact rock and for the fractures. The numerical modelling was performed with the two-dimensional code UDEC, and the rock block models were generated from 2D trace sections extracted from the 3D Discrete Fracture Network (DFN) model. Assumptions and uncertainties related to the set-up of the model are considered. The numerical model was set-up to simulate a plain strain-loading test. Different boundary conditions were applied on the model for simulating stress conditions (I) in the undisturbed rock mass, and (II) at the proximity of a tunnel. In order to assess the reliability of the model sensitivity analyses have been conducted on some rock block models for defining the dependency of mechanical properties to in situ stresses, the influence of boundary conditions, rock material and joint constitutive models used to simulate the behaviour of intact rock and fractures, domain size and anisotropy. To

  1. Consensus clustering approach to group brain connectivity matrices

    Javier Rasero

    2017-10-01

    Full Text Available A novel approach rooted on the notion of consensus clustering, a strategy developed for community detection in complex networks, is proposed to cope with the heterogeneity that characterizes connectivity matrices in health and disease. The method can be summarized as follows: (a define, for each node, a distance matrix for the set of subjects by comparing the connectivity pattern of that node in all pairs of subjects; (b cluster the distance matrix for each node; (c build the consensus network from the corresponding partitions; and (d extract groups of subjects by finding the communities of the consensus network thus obtained. Different from the previous implementations of consensus clustering, we thus propose to use the consensus strategy to combine the information arising from the connectivity patterns of each node. The proposed approach may be seen either as an exploratory technique or as an unsupervised pretraining step to help the subsequent construction of a supervised classifier. Applications on a toy model and two real datasets show the effectiveness of the proposed methodology, which represents heterogeneity of a set of subjects in terms of a weighted network, the consensus matrix.

  2. Quantum group structure and local fields in the algebraic approach to 2D gravity

    Schnittger, J.

    1995-07-01

    This review contains a summary of the work by J.-L. Gervais and the author on the operator approach to 2d gravity. Special emphasis is placed on the construction of local observables — the Liouville exponentials and the Liouville field itself — and the underlying algebra of chiral vertex operators. The double quantum group structure arising from the presence of two screening charges is discussed and the generalized algebra and field operators are derived. In the last part, we show that our construction gives rise to a natural definition of a quantum tau function, which is a noncommutative version of the classical group-theoretic representation of the Liouville fields by Leznov and Saveliev.

  3. Effective field renormalization group approach for Ising lattice spin systems

    Fittipaldi, Ivon P.

    1994-03-01

    A new applicable real-space renormalization group framework (EFRG) for computing the critical properties of Ising lattice spin systems is presented. The method, which follows up the same strategy of the mean-field renormalization group scheme (MFRG), is based on rigorous Ising spin identities and utilizes a convenient differential operator expansion technique. Within this scheme, in contrast with the usual mean-field type of equation of state, all the relevant self-spin correlations are taken exactly into account. The results for the critical coupling and the critical exponent v, for the correlation length, are very satisfactory and it is shown that this technique leads to rather accurate results which represent a remarkable improvement on those obtained from the standard MFRG method. In particular, it is shown that the present EFRG approach correctly distinguishes the geometry of the lattice structure even when employing its simplest size-cluster version. Owing to its simplicity we also comment on the wide applicability of the present method to problems in crystalline and disordered Ising spin systems.

  4. A game-theoretic approach for calibration of low-cost magnetometers under noise uncertainty

    Siddharth, S.; Ali, A. S.; El-Sheimy, N.; Goodall, C. L.; Syed, Z. F.

    2012-02-01

    Pedestrian heading estimation is a fundamental challenge in Global Navigation Satellite System (GNSS)-denied environments. Additionally, the heading observability considerably degrades in low-speed mode of operation (e.g. walking), making this problem even more challenging. The goal of this work is to improve the heading solution when hand-held personal/portable devices, such as cell phones, are used for positioning and to improve the heading estimation in GNSS-denied signal environments. Most smart phones are now equipped with self-contained, low cost, small size and power-efficient sensors, such as magnetometers, gyroscopes and accelerometers. A magnetometer needs calibration before it can be properly employed for navigation purposes. Magnetometers play an important role in absolute heading estimation and are embedded in many smart phones. Before the users navigate with the phone, a calibration is invoked to ensure an improved signal quality. This signal is used later in the heading estimation. In most of the magnetometer-calibration approaches, the motion modes are seldom described to achieve a robust calibration. Also, suitable calibration approaches fail to discuss the stopping criteria for calibration. In this paper, the following three topics are discussed in detail that are important to achieve proper magnetometer-calibration results and in turn the most robust heading solution for the user while taking care of the device misalignment with respect to the user: (a) game-theoretic concepts to attain better filter parameter tuning and robustness in noise uncertainty, (b) best maneuvers with focus on 3D and 2D motion modes and related challenges and (c) investigation of the calibration termination criteria leveraging the calibration robustness and efficiency.

  5. A game-theoretic approach for calibration of low-cost magnetometers under noise uncertainty

    Siddharth, S; Ali, A S; El-Sheimy, N; Goodall, C L; Syed, Z F

    2012-01-01

    Pedestrian heading estimation is a fundamental challenge in Global Navigation Satellite System (GNSS)-denied environments. Additionally, the heading observability considerably degrades in low-speed mode of operation (e.g. walking), making this problem even more challenging. The goal of this work is to improve the heading solution when hand-held personal/portable devices, such as cell phones, are used for positioning and to improve the heading estimation in GNSS-denied signal environments. Most smart phones are now equipped with self-contained, low cost, small size and power-efficient sensors, such as magnetometers, gyroscopes and accelerometers. A magnetometer needs calibration before it can be properly employed for navigation purposes. Magnetometers play an important role in absolute heading estimation and are embedded in many smart phones. Before the users navigate with the phone, a calibration is invoked to ensure an improved signal quality. This signal is used later in the heading estimation. In most of the magnetometer-calibration approaches, the motion modes are seldom described to achieve a robust calibration. Also, suitable calibration approaches fail to discuss the stopping criteria for calibration. In this paper, the following three topics are discussed in detail that are important to achieve proper magnetometer-calibration results and in turn the most robust heading solution for the user while taking care of the device misalignment with respect to the user: (a) game-theoretic concepts to attain better filter parameter tuning and robustness in noise uncertainty, (b) best maneuvers with focus on 3D and 2D motion modes and related challenges and (c) investigation of the calibration termination criteria leveraging the calibration robustness and efficiency. (paper)

  6. On the electric dipole moments of small sodium clusters from different theoretical approaches

    Aguado, Andrés; Largo, Antonio; Vega, Andrés; Balbás, Luis Carlos

    2012-01-01

    Graphical abstract: The dipole moments and polarizabilities of a few isomers of sodium clusters of selected sizes (n = 13, 14, 16) are calculated using density functional theory methods as well as ab initio MP2, CASSCF, and MR-CI methods. Among the density functional approaches, we consider the usual local density and generalized gradient approximations, as well as a recent van der Waals self-consistent functional accounting for non-local dispersion interactions. Highlights: ► Dipole moment and polarizability of sodium clusters from DFT and ab initio methods. ► New van der Waals selfconsistent implementation of non-local dispersion interactions. ► New starting isomeric geometries from extensive search of global minimum structures. ► Good agreement with recent experiments at cryogenic temperatures. - Abstract: The dipole moments of Na n clusters in the size range 10 n clusters of selected sizes (n = 13, 14, 16), obtained recently through an extensive unbiased search of the global minimum structures, and using density functional theory methods as well as ab initio MP2, CASSCF, and MR-CI methods. Among the density functional approaches, we consider the usual local density and generalized gradient approximations, as well as a recent van der Waals self-consistent functional accounting for non-local dispersion interactions. Both non-local pseudopotentials and all-electron implementations are employed and compared in order to assess the possible contribution of the core electrons to the electric dipole moments. Our new geometries possess significantly smaller electric dipole moments than previous density functional results, mostly when combined with the van der Waals exchange–correlation functional. However, although the agreement with experiment clearly improves upon previous calculations, the theoretical dipole moments are still about one order of magnitude larger than the experimental values, suggesting that the correct global minimum structures have not been

  7. Does Macaulay Duration Provide The Most Cost-Effective Immunization Method – A Theoretical Approach

    Zaremba Leszek

    2017-02-01

    Full Text Available In the following, we offer a theoretical approach that attempts to explain (Comments 1-3 why and when the Macaulay duration concept happens to be a good approximation of a bond’s price sensitivity. We are concerned with the basic immunization problem with a single liability to be discharged at a future time q. Our idea is to divide the class K of all shifts a(t of a term structure of interest rates s(t into many classes and then to find a sufficient and necessary condition a given bond portfolio, dependent on a class of shifts, must satisfy to secure immunization at time q against all shifts a(t from that class. For this purpose, we introduce the notions of dedicated duration and dedicated convexity. For each class of shifts, we show how to choose from a bond market under consideration a portfolio with maximal dedicated convexity among all immunizing portfolios. We demonstrate that the portfolio yields the maximal unanticipated rate of return and appears to be uniquely determined as a barbell strategy (portfolio built up with 2 zero-coupon bearing bonds with maximal and respective minimal dedicated durations. Finally, an open problem addressed to researchers performing empirical studies is formulated.

  8. Game Theoretical Approaches for Transport-Aware Channel Selection in Cognitive Radio Networks

    Chen Shih-Ho

    2010-01-01

    Full Text Available Effectively sharing channels among secondary users (SUs is one of the greatest challenges in cognitive radio network (CRN. In the past, many studies have proposed channel selection schemes at the physical or the MAC layer that allow SUs swiftly respond to the spectrum states. However, they may not lead to enhance performance due to slow response of the transport layer flow control mechanism. This paper presents a cross-layer design framework called Transport Aware Channel Selection (TACS scheme to optimize the transport throughput based on states, such as RTT and congestion window size, of TCP flow control mechanism. We formulate the TACS problem as two different game theoretic approaches: Selfish Spectrum Sharing Game (SSSG and Cooperative Spectrum Sharing Game (CSSG and present novel distributed heuristic algorithms to optimize TCP throughput. Computer simulations show that SSSG and CSSG could double the SUs throughput of current MAC-based scheme when primary users (PUs use their channel infrequently, and with up to 12% to 100% throughput increase when PUs are more active. The simulation results also illustrated that CSSG performs up to 20% better than SSSG in terms of the throughput.

  9. A Markov game theoretic data fusion approach for cyber situational awareness

    Shen, Dan; Chen, Genshe; Cruz, Jose B., Jr.; Haynes, Leonard; Kruger, Martin; Blasch, Erik

    2007-04-01

    This paper proposes an innovative data-fusion/ data-mining game theoretic situation awareness and impact assessment approach for cyber network defense. Alerts generated by Intrusion Detection Sensors (IDSs) or Intrusion Prevention Sensors (IPSs) are fed into the data refinement (Level 0) and object assessment (L1) data fusion components. High-level situation/threat assessment (L2/L3) data fusion based on Markov game model and Hierarchical Entity Aggregation (HEA) are proposed to refine the primitive prediction generated by adaptive feature/pattern recognition and capture new unknown features. A Markov (Stochastic) game method is used to estimate the belief of each possible cyber attack pattern. Game theory captures the nature of cyber conflicts: determination of the attacking-force strategies is tightly coupled to determination of the defense-force strategies and vice versa. Also, Markov game theory deals with uncertainty and incompleteness of available information. A software tool is developed to demonstrate the performance of the high level information fusion for cyber network defense situation and a simulation example shows the enhanced understating of cyber-network defense.

  10. A Hybrid Chaotic and Number Theoretic Approach for Securing DICOM Images

    Jeyamala Chandrasekaran

    2017-01-01

    Full Text Available The advancements in telecommunication and networking technologies have led to the increased popularity and widespread usage of telemedicine. Telemedicine involves storage and exchange of large volume of medical records for remote diagnosis and improved health care services. Images in medical records are characterized by huge volume, high redundancy, and strong correlation among adjacent pixels. This research work proposes a novel idea of integrating number theoretic approach with Henon map for secure and efficient encryption. Modular exponentiation of the primitive roots of the chosen prime in the range of its residual set is employed in the generation of two-dimensional array of keys. The key matrix is permuted and chaotically controlled by Henon map to decide the encryption keys for every pixel of DICOM image. The proposed system is highly secure because of the randomness introduced due to the application of modular exponentiation key generation and application of Henon maps for permutation of keys. Experiments have been conducted to analyze key space, key sensitivity, avalanche effect, correlation distribution, entropy, and histograms. The corresponding results confirm the strength of the proposed design towards statistical and differential crypt analysis. The computational requirements for encryption/decryption have been reduced significantly owing to the reduced number of computations in the process of encryption/decryption.

  11. Power and Law in Enlightened Absolutism – Carl Gottlieb Svarez’ Theoretical and Practical Approach

    Milan Kuhli

    2013-01-01

    Full Text Available The term Enlightened Absolutism reflects a certain tension between its two components. This tension is in a way a continuation of the dichotomy between power on one hand and law on the other. The present paper shall provide an analysis of these two concepts from the perspective of Carl Gottlieb Svarez, who, in his position as a high-ranking Prussian civil servant and legal reformist, had unparalleled influence on the legislative history of the Prussian states towards the end of the 18th century. Working side-by-side with Johann Heinrich Casimir von Carmer, who held the post of Prussian minister of justice from 1779 to 1798, Svarez was able to make use of his talent for reforming and legislating. From 1780 to 1794 he was primarily responsible for the elaboration of the codification of the Prussian private law – the »Allgemeines Landrecht für die Preußischen Staaten« in 1794. In the present paper, Svarez’ approach to the relation between law and power shall be analysed on two different levels. Firstly, on a theoretical level, the reformist’s thoughts and reflections as laid down in his numerous works, papers and memorandums, shall be discussed. Secondly, on a practical level, the question of the extent to which he implemented his ideas in Prussian legal reality shall be explored.

  12. Strategic exploration of battery waste management: A game-theoretic approach.

    Kaushal, Rajendra Kumar; Nema, Arvind K; Chaudhary, Jyoti

    2015-07-01

    Electronic waste or e-waste is the fastest growing stream of solid waste today. It contains both toxic substances as well as valuable resources. The present study uses a non-cooperative game-theoretic approach for efficient management of e-waste, particularly batteries that contribute a major portion of any e-waste stream and further analyses the economic consequences of recycling of these obsolete, discarded batteries. Results suggest that the recycler would prefer to collect the obsolete batteries directly from the consumer rather than from the manufacturer, only if, the incentive return to the consumer is less than 33.92% of the price of the battery, the recycling fee is less than 6.46% of the price of the battery, and the price of the recycled material is more than 31.08% of the price of the battery. The manufacturer's preferred choice of charging a green tax from the consumer can be fruitful for the battery recycling chain. © The Author(s) 2015.

  13. The game as strategy for approach to sexuality with adolescents: theoretical-methodological reflections

    Vânia de Souza

    Full Text Available ABSTRACT Objective: To describe the Papo Reto [Straight Talk] game and reflect on its theoretical-methodological basis. Method: Analytical study on the process of elaboration of the Papo Reto online game, destined to adolescents aged 15-18 years, with access to the Game between 2014 and 2015. Results: the interactions of 60 adolescents from Belo Horizonte and São Paulo constituted examples of the potentialities of the Game to favor the approach to sexuality with adolescents through simulation of reality, invention and interaction. Based on those potentialities, four thinking categories were discussed: the game as pedagogic device; the game as simulation of realities; the game as device for inventive learning; and the game empowering the interaction. Conclusion: By permitting that the adolescents take risks on new ways, the Game allows them to become creative and active in the production of senses, in the creation of their discourses and in the ways of thinking, feeling and acting in the sexuality field.

  14. A Game Theoretic Approach to Minimize the Completion Time of Network Coded Cooperative Data Exchange

    Douik, Ahmed S.

    2014-05-11

    In this paper, we introduce a game theoretic framework for studying the problem of minimizing the completion time of instantly decodable network coding (IDNC) for cooperative data exchange (CDE) in decentralized wireless network. In this configuration, clients cooperate with each other to recover the erased packets without a central controller. Game theory is employed herein as a tool for improving the distributed solution by overcoming the need for a central controller or additional signaling in the system. We model the session by self-interested players in a non-cooperative potential game. The utility function is designed such that increasing individual payoff results in a collective behavior achieving both a desirable system performance in a shared network environment and the Pareto optimal solution. Through extensive simulations, our approach is compared to the best performance that could be found in the conventional point-to-multipoint (PMP) recovery process. Numerical results show that our formulation largely outperforms the conventional PMP scheme in most practical situations and achieves a lower delay.

  15. Intraplate seismicity in Canada: a graph theoretic approach to data analysis and interpretation

    K. Vasudevan

    2010-10-01

    Full Text Available Intraplate seismicity occurs in central and northern Canada, but the underlying origin and dynamics remain poorly understood. Here, we apply a graph theoretic approach to characterize the statistical structure of spatiotemporal clustering exhibited by intraplate seismicity, a direct consequence of the underlying nonlinear dynamics. Using a recently proposed definition of "recurrences" based on record breaking processes (Davidsen et al., 2006, 2008, we have constructed directed graphs using catalogue data for three selected regions (Region 1: 45°−48° N/74°−80° W; Region 2: 51°−55° N/77°−83° W; and Region 3: 56°−70° N/65°−95° W, with attributes drawn from the location, origin time and the magnitude of the events. Based on comparisons with a null model derived from Poisson distribution or Monte Carlo shuffling of the catalogue data, our results provide strong evidence in support of spatiotemporal correlations of seismicity in all three regions considered. Similar evidence for spatiotemporal clustering has been documented using seismicity catalogues for southern California, suggesting possible similarities in underlying earthquake dynamics of both regions despite huge differences in the variability of seismic activity.

  16. Perspectives on Cybersecurity Information Sharing among Multiple Stakeholders Using a Decision-Theoretic Approach.

    He, Meilin; Devine, Laura; Zhuang, Jun

    2018-02-01

    The government, private sectors, and others users of the Internet are increasingly faced with the risk of cyber incidents. Damage to computer systems and theft of sensitive data caused by cyber attacks have the potential to result in lasting harm to entities under attack, or to society as a whole. The effects of cyber attacks are not always obvious, and detecting them is not a simple proposition. As the U.S. federal government believes that information sharing on cybersecurity issues among organizations is essential to safety, security, and resilience, the importance of trusted information exchange has been emphasized to support public and private decision making by encouraging the creation of the Information Sharing and Analysis Center (ISAC). Through a decision-theoretic approach, this article provides new perspectives on ISAC, and the advent of the new Information Sharing and Analysis Organizations (ISAOs), which are intended to provide similar benefits to organizations that cannot fit easily into the ISAC structure. To help understand the processes of information sharing against cyber threats, this article illustrates 15 representative information sharing structures between ISAC, government, and other participating entities, and provide discussions on the strategic interactions between different stakeholders. This article also identifies the costs of information sharing and information security borne by different parties in this public-private partnership both before and after cyber attacks, as well as the two main benefits. This article provides perspectives on the mechanism of information sharing and some detailed cost-benefit analysis. © 2017 Society for Risk Analysis.

  17. Theoretical approach to description of some corrosion product transport processes in PWRs primary circuit

    Zmitko, M.

    1990-10-01

    The behavior and mass transport of corrosion products in primary circuits of PWR type reactors are described assuming that the products occur in ionic form, in colloidal form (about 0.01-0.6 μm in size) and in particulate form. The transport of the soluble form is treated as a diffusion process. For the colloidal form, allowance is made for its Van der Waals attraction and repulsion interaction with the surfaces. For particles and their agglomerates, the hydrodynamical effects of the flowing liquid on the agglomerate breakdown and re-formation of the particle suspension are taken into account. Efforts were made to employ theoretical relations rather than particular experimental data, for the conclusions to be applicable to different facilities. It is believed that the complex approach to the problem can contribute to gaining insight into the role of the individual factors and processes involved, particularly as regards colloidal particles whose effect on the formation of radiation fields is not yet fully understood. (author). 3 figs., 10 refs

  18. Power Transmission Scheduling for Generators in a Deregulated Environment Based on a Game-Theoretic Approach

    Bingtuan Gao

    2015-12-01

    Full Text Available In a deregulated environment of the power market, in order to lower their energy price and guarantee the stability of the power network, appropriate transmission lines have to be considered for electricity generators to sell their energy to the end users. This paper proposes a game-theoretic power transmission scheduling for multiple generators to lower their wheeling cost. Based on the embedded cost method, a wheeling cost model consisting of congestion cost, cost of losses and cost of transmission capacity is presented. By assuming each generator behaves in a selfish and rational way, the competition among the multiple generators is formulated as a non-cooperative game, where the players are the generators and the strategies are their daily schedules of power transmission. We will prove that there exists at least one pure-strategy Nash equilibrium of the formulated power transmission game. Moreover, a distributed algorithm will be provided to realize the optimization in terms of minimizing the wheeling cost. Finally, simulations were performed and discussed to verify the feasibility and effectiveness of the proposed non-cooperative game approach for the generators in a deregulated environment.

  19. A Game Theoretic Approach to Minimize the Completion Time of Network Coded Cooperative Data Exchange

    Douik, Ahmed S.; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim; Sorour, Sameh; Tembine, Hamidou

    2014-01-01

    In this paper, we introduce a game theoretic framework for studying the problem of minimizing the completion time of instantly decodable network coding (IDNC) for cooperative data exchange (CDE) in decentralized wireless network. In this configuration, clients cooperate with each other to recover the erased packets without a central controller. Game theory is employed herein as a tool for improving the distributed solution by overcoming the need for a central controller or additional signaling in the system. We model the session by self-interested players in a non-cooperative potential game. The utility function is designed such that increasing individual payoff results in a collective behavior achieving both a desirable system performance in a shared network environment and the Pareto optimal solution. Through extensive simulations, our approach is compared to the best performance that could be found in the conventional point-to-multipoint (PMP) recovery process. Numerical results show that our formulation largely outperforms the conventional PMP scheme in most practical situations and achieves a lower delay.

  20. A game theoretic approach to a finite-time disturbance attenuation problem

    Rhee, Ihnseok; Speyer, Jason L.

    1991-01-01

    A disturbance attenuation problem over a finite-time interval is considered by a game theoretic approach where the control, restricted to a function of the measurement history, plays against adversaries composed of the process and measurement disturbances, and the initial state. A zero-sum game, formulated as a quadratic cost criterion subject to linear time-varying dynamics and measurements, is solved by a calculus of variation technique. By first maximizing the quadratic cost criterion with respect to the process disturbance and initial state, a full information game between the control and the measurement residual subject to the estimator dynamics results. The resulting solution produces an n-dimensional compensator which expresses the controller as a linear combination of the measurement history. A disturbance attenuation problem is solved based on the results of the game problem. For time-invariant systems it is shown that under certain conditions the time-varying controller becomes time-invariant on the infinite-time interval. The resulting controller satisfies an H(infinity) norm bound.

  1. THE EASTERN PARTNERSHIP AS PART OF THE EU FOREIGN POLICY: A REVIEW OF THEORETICAL APPROACHES

    Andrei SCRINIC

    2014-10-01

    Full Text Available The Eastern Partnership (2009 as a component part of the European Neighbourhood Policy is a tool that aims at the economic integration and political cooperation of the countries that are included in this project by signing association and free trade agreements with the European Union (EU. The recent events in Ukraine have revealed the possibility of these countries to become EU member states depending on the progress made, which is confirmed by many European experts. However, there are big differences among the Eastern Partnership countries on their way to EU integration on the background of the strong pressure from Russia, aimed to suppress any pro-European manifestations of such countries. Despite the sharpening of geopolitical challenges, the EU continues to use the traditional ways of enlargement and deepening of cooperation processes with the Eastern Neighbourhood. This paper aims at reviewing the theoretical approaches through which the EU, as a normative power, exerts major influence on the Eastern Partnership (EaP countries by extending the neofunctional practices, intergovernmental cooperation and the constructivist model. However, in view of reaching the soft power objectives, we aim at transforming and strengthening the EU positions in the context of amplified economic and political-ideological problems at regional level.

  2. Combination of real options and game-theoretic approach in investment analysis

    Arasteh, Abdollah

    2016-09-01

    Investments in technology create a large amount of capital investments by major companies. Assessing such investment projects is identified as critical to the efficient assignment of resources. Viewing investment projects as real options, this paper expands a method for assessing technology investment decisions in the linkage existence of uncertainty and competition. It combines the game-theoretic models of strategic market interactions with a real options approach. Several key characteristics underlie the model. First, our study shows how investment strategies rely on competitive interactions. Under the force of competition, firms hurry to exercise their options early. The resulting "hurry equilibrium" destroys the option value of waiting and involves violent investment behavior. Second, we get best investment policies and critical investment entrances. This suggests that integrating will be unavoidable in some information product markets. The model creates some new intuitions into the forces that shape market behavior as noticed in the information technology industry. It can be used to specify best investment policies for technology innovations and adoptions, multistage R&D, and investment projects in information technology.

  3. Force-induced bone growth and adaptation: A system theoretical approach to understanding bone mechanotransduction

    Maldonado, Solvey; Findeisen, Rolf

    2010-01-01

    The modeling, analysis, and design of treatment therapies for bone disorders based on the paradigm of force-induced bone growth and adaptation is a challenging task. Mathematical models provide, in comparison to clinical, medical and biological approaches an structured alternative framework to understand the concurrent effects of the multiple factors involved in bone remodeling. By now, there are few mathematical models describing the appearing complex interactions. However, the resulting models are complex and difficult to analyze, due to the strong nonlinearities appearing in the equations, the wide range of variability of the states, and the uncertainties in parameters. In this work, we focus on analyzing the effects of changes in model structure and parameters/inputs variations on the overall steady state behavior using systems theoretical methods. Based on an briefly reviewed existing model that describes force-induced bone adaptation, the main objective of this work is to analyze the stationary behavior and to identify plausible treatment targets for remodeling related bone disorders. Identifying plausible targets can help in the development of optimal treatments combining both physical activity and drug-medication. Such treatments help to improve/maintain/restore bone strength, which deteriorates under bone disorder conditions, such as estrogen deficiency.

  4. Theoretical studies on the effect of benzene and thiophene groups on the charge transport properties of Isoindigo and its derivatives

    Jia, Xu-Bo; Wei, Hui-Ling; Shi, Ya-Ting; Shi, Ya-Rui; Liu, Yu-Fang

    2017-12-01

    In this work, the charge transport properties of Isoindigo (II) and its derivatives which have the same hexyl chain were theoretically investigated by the Marcus-Hush theory combined with density functional theory (DFT). Here we demonstrate that the changes of benzene and thiophene groups in molecular structure have an important influence on the charge transport properties of organic semiconductor. The benzene rings of II are replaced by thiophenes to form the thienoisoindigo (TII), and the addition of benzene rings to the TII form the benzothienoisoindigo (BTII). The results show that benzene rings and thiophenes change the chemical structure of crystal molecules, which lead to different molecule stacking, thus, the length of hydrogen bond was changed. A shorter intermolecular hydrogen bond lead to tighter molecular stacking, which reduces the center-to-center distance and enhances the ability of charge transfer. At the same time, we theoretically demonstrated that II and BTII are the ambipolar organic semiconductor. BTII has better carrier mobility. The hole mobility far greater than electron mobility in TII, which is p-type organic semiconductor. Among all hopping path, we find that the distance of face-to-face stacking in II is the shortest and the electron-transport electronic coupling Ve is the largest, but II has not a largest anisotropic mobility, because the reorganization energy has a greater influence on the mobility than the electronic coupling. This work is helpful for designing ambipolar organic semiconductor materials with higher charge transport properties by introducing benzene ring and thiophene.

  5. [Specific developmental language disorder: a theoretical approach to its diagnosis, aetiology and clinical symptoms].

    Castro-Rebolledo, R; Giraldo-Prieto, M; Hincapié-Henao, L; Lopera, F; Pineda, D A

    This article presents an updated review about the definition, diagnostic criteria, classifications, etiology and the evolution of the specific language impairment (SLI). The specific language impairment is characterized by a developmental language delay and an impaired language, that persist over time and it is not explained by sensorial, motor and mental disabilities, neither by psycopathological disorders, socio-emotional deprivation, nor brain injury. The diagnosis is based on exclusional criteria. Some researchers propose different classifications considering the children performance in language comprehension and language production. Genetical linkage to the FOXP2 gen in the SPCH1 region of the chromosome 7 and to the chromosomes 13, 16 y 19 has been reported. The neuroimage studies have shown alterations in the volume and perfusion of some brain structures related to language. The manifestations of SLI may change during the development of the children and may disturb the self-esteem, the academic performance and the social abilities. The variability in the linguistic and cognitive performance, and the variety in the etiological findings in children with SLI, don't allow to settle the affected population as an homogeneous group. Different theoretical positions have emerged as a consequence of this condition.

  6. Group-theoretical deduction of a dyadic Tamm-Dancoff equation by using a matrix-valued generator coordinate

    Nishiyama, Seiya; Morita, Hiroyuki; Ohnishi, Hiromasa

    2004-01-01

    The traditional Tamm-Dancoff (TD) method is one of the standard procedures for solving the Schroedinger equation of fermion many-body systems. However, it meets a serious difficulty when an instability occurs in the symmetry-adapted ground state of the independent particle approximation (IPA) and when the stable IPA ground state becomes of broken symmetry. If one uses the stable but broken symmetry IPA ground state as the starting approximation, TD wave functions also become of broken symmetry. On the contrary, if we start from a symmetry-adapted but unstable wave function, the convergence of the TD expansion becomes bad. Thus, the requirements of symmetry and rapid convergence are not in general compatible in the conventional TD expansion of the systems with strong collective correlations. Along the same line as Fukutome's, we give a group-theoretical deduction of a U(n) dyadic TD equation by using a matrix-valued generator coordinate

  7. Theoretical Antecedents of Standing at Work: An Experience Sampling Approach Using the Theory of Planned Behavior.

    Meyer, M Renée Umstattd; Wu, Cindy; Walsh, Shana M

    2016-01-01

    Time spent sitting has been associated with an increased risk of diabetes, cancer, obesity, and mental health impairments. However, 75% of Americans spend most of their days sitting, with work-sitting accounting for 63% of total daily sitting time. Little research examining theory-based antecedents of standing or sitting has been conducted. This lack of solid groundwork makes it difficult to design effective intervention strategies to decrease sitting behaviors. Using the Theory of Planned Behavior (TPB) as our theoretical lens to better understand factors related with beneficial standing behaviors already being practiced, we examined relationships between TPB constructs and time spent standing at work among "positive deviants" (those successful in behavior change). Experience sampling methodology (ESM), 4 times a day (midmorning, before lunch, afternoon, and before leaving work) for 5 consecutive workdays (Monday to Friday), was used to assess employees' standing time. TPB scales assessing attitude (α = 0.81-0.84), norms (α = 0.83), perceived behavioral control (α = 0.77), and intention (α = 0.78) were developed using recommended methods and collected once on the Friday before the ESM surveys started. ESM data are hierarchically nested, therefore we tested our hypotheses using multilevel structural equation modeling with Mplus. Hourly full-time university employees (n = 50; 70.6% female, 84.3% white, mean age = 44 (SD = 11), 88.2% in full-time staff positions) with sedentary occupation types (time at desk while working ≥6 hours/day) participated. A total of 871 daily surveys were completed. Only perceived behavioral control (β = 0.45, p work-standing at the event-level (model fit: just fit); mediation through intention was not supported. This is the first study to examine theoretical antecedents of real-time work-standing in a naturalistic field setting among positive deviants. These relationships should be further examined, and behavioral intervention

  8. Theoretical Antecedents of Standing at Work: An Experience Sampling Approach Using the Theory of Planned Behavior

    M. Renée Umstattd Meyer

    2016-09-01

    Full Text Available Time spent sitting has been associated with an increased risk of diabetes, cancer, obesity, and mental health impairments. However, 75% of Americans spend most of their days sitting, with work-sitting accounting for 63% of total daily sitting time. Little research examining theory-based antecedents of standing or sitting has been conducted. This lack of solid groundwork makes it difficult to design effective intervention strategies to decrease sitting behaviors. Using the Theory of Planned Behavior (TPB as our theoretical lens to better understand factors related with beneficial standing behaviors already being practiced, we examined relationships between TPB constructs and time spent standing at work among “positive deviants” (those successful in behavior change. Experience sampling methodology (ESM, 4 times a day (midmorning, before lunch, afternoon, and before leaving work for 5 consecutive workdays (Monday to Friday, was used to assess employees’ standing time. TPB scales assessing attitude (α = 0.81–0.84, norms (α = 0.83, perceived behavioral control (α = 0.77, and intention (α = 0.78 were developed using recommended methods and collected once on the Friday before the ESM surveys started. ESM data are hierarchically nested, therefore we tested our hypotheses using multilevel structural equation modeling with Mplus. Hourly full-time university employees (n = 50; 70.6% female, 84.3% white, mean age = 44 (SD = 11, 88.2%in full-time staff positions with sedentary occupation types (time at desk while working ≥6 hours/day participated. A total of 871 daily surveys were completed. Only perceived behavioral control (β = 0.45, p < 0.05 was related with work-standing at the event-level (model fit: just fit; mediation through intention was not supported. This is the first study to examine theoretical antecedents of real-time work-standing in a naturalistic field setting among positive deviants. These relationships should be further

  9. On the electric dipole moments of small sodium clusters from different theoretical approaches

    Aguado, Andres, E-mail: aguado@metodos.fam.cie.uva.es [Departamento de Fisica Teorica, Atomica, y Optica, Universidad de Valladolid (Spain); Largo, Antonio, E-mail: alargo@qf.uva.es [Departamento de Quimica Fisica y Quimica Inorganica, Universidad de Valladolid (Spain); Vega, Andres, E-mail: vega@fta.uva.es [Departamento de Fisica Teorica, Atomica, y Optica, Universidad de Valladolid (Spain); Balbas, Luis Carlos, E-mail: balbas@fta.uva.es [Departamento de Fisica Teorica, Atomica, y Optica, Universidad de Valladolid (Spain)

    2012-05-03

    Graphical abstract: The dipole moments and polarizabilities of a few isomers of sodium clusters of selected sizes (n = 13, 14, 16) are calculated using density functional theory methods as well as ab initio MP2, CASSCF, and MR-CI methods. Among the density functional approaches, we consider the usual local density and generalized gradient approximations, as well as a recent van der Waals self-consistent functional accounting for non-local dispersion interactions. Highlights: Black-Right-Pointing-Pointer Dipole moment and polarizability of sodium clusters from DFT and ab initio methods. Black-Right-Pointing-Pointer New van der Waals selfconsistent implementation of non-local dispersion interactions. Black-Right-Pointing-Pointer New starting isomeric geometries from extensive search of global minimum structures. Black-Right-Pointing-Pointer Good agreement with recent experiments at cryogenic temperatures. - Abstract: The dipole moments of Na{sub n} clusters in the size range 10 < n < 20, recently measured at very low temperature (20 K), are much smaller than predicted by standard density functional methods. On the other hand, the calculated static dipole polarizabilities in that range of sizes deviate non-systematically from the measured ones, depending on the employed first principles approach. In this work we calculate the dipole moments and polarizabilities of a few isomers of Na{sub n} clusters of selected sizes (n = 13, 14, 16), obtained recently through an extensive unbiased search of the global minimum structures, and using density functional theory methods as well as ab initio MP2, CASSCF, and MR-CI methods. Among the density functional approaches, we consider the usual local density and generalized gradient approximations, as well as a recent van der Waals self-consistent functional accounting for non-local dispersion interactions. Both non-local pseudopotentials and all-electron implementations are employed and compared in order to assess the possible

  10. The group-theoretical approach to the description of nuclear states

    Baktybaev, K.

    2001-01-01

    Study of symmetrical environmental properties, including nuclei, nuclear particles, atoms and molecules has very important, and sometimes determinative meaning. The role of visible symmetry, in other words of the world beauty is generally known, and studied for a long time. The internal symmetry of material world (isotopic, angular, gauge, dynamic etc.), playing vitally important significance for its structure, creation and development has been widely studied for last years. The development of conception of dynamic symmetry and supersymmetry in the structure of nuclear system condition and their supplement under studies of specific nuclei properties is considered in the present article. The next section includes the summary of the main point of dynamic symmetry and its connection to corresponding Lie algebra and techniques of physical operators construction through generators of chosen algebra and its subalgebra. Section 3 states the dynamic-symmetric properties of atomic nuclei collective states, which are described by the model of interactive bosons. Section 4 is dedicated to conception of dynamic supersymmetry, its supplement under structure study of quasi-particle and collective states of nuclei and all interactions. In particular, the theory is applied for study of fermion and boson states in the even isotopes Pd, Dy and Er

  11. Theoretical Antecedents of Standing at Work: An Experience Sampling Approach Using the Theory of Planned Behavior

    Meyer, M. Renée Umstattd; Wu, Cindy; Walsh, Shana M.

    2016-01-01

    Time spent sitting has been associated with an increased risk of diabetes, cancer, obesity, and mental health impairments. However, 75% of Americans spend most of their days sitting, with work-sitting accounting for 63% of total daily sitting time. Little research examining theory-based antecedents of standing or sitting has been conducted. This lack of solid groundwork makes it difficult to design effective intervention strategies to decrease sitting behaviors. Using the Theory of Planned Behavior (TPB) as our theoretical lens to better understand factors related with beneficial standing behaviors already being practiced, we examined relationships between TPB constructs and time spent standing at work among “positive deviants” (those successful in behavior change). Experience sampling methodology (ESM), 4 times a day (midmorning, before lunch, afternoon, and before leaving work) for 5 consecutive workdays (Monday to Friday), was used to assess employees' standing time. TPB scales assessing attitude (α = 0.81–0.84), norms (α = 0.83), perceived behavioral control (α = 0.77), and intention (α = 0.78) were developed using recommended methods and collected once on the Friday before the ESM surveys started. ESM data are hierarchically nested, therefore we tested our hypotheses using multilevel structural equation modeling with Mplus. Hourly full-time university employees (n = 50; 70.6% female, 84.3% white, mean age = 44 (SD = 11), 88.2% in full-time staff positions) with sedentary occupation types (time at desk while working ≥6 hours/day) participated. A total of 871 daily surveys were completed. Only perceived behavioral control (β = 0.45, p deviance approach to enhance perceived behavioral control, in addition to implementing environmental changes like installing standing desks. PMID:29546189

  12. Theoretical Approaches in the Context of Spatial Planning Decisions and the Relation with Urban Sustainability

    Kumlu, Kadriye Burcu Yavuz; Tüdeş, Şule

    2017-10-01

    The sustainability agenda has maintained its importance since the days, when the production system took its capitalist form, as well as the population in the urban areas started to rise. Increasing number of both goods and the people have caused the degradation of the certain systems, which generate the urban areas. These systems could mainly be classified as social, environmental, physical and economical systems. Today, urban areas still have difficulty to protect those systems, due to the significant demand of the population. Therefore, studies related with the sustainable issues are significant in the sense of continuity of the urban systems. Therefore, in this paper, those studies in the context of the effects of physical decisions taken in the spatial planning process on urban sustainability, will be examined. The components of the physical decisions are limited to land use, density and design. Land use decisions will be examined in the context of mixed land use. On the other hand, decisions related with density will be analyzed in the sense of population density and floor area ratio (FAR). Besides, design decisions will be examined, by linking them with neighborhood design criteria. Additionally, the term of urban sustainability will only be limited to its social and environmental contexts in this study. Briefly stated, studies in the sustainable literature concerned with the effects of land use, density and design decisions taken in the spatial planning process on the social and environmental sustainability will be examined in this paper. After the compilation and the analyze of those studies, a theoretical approach will be proposed to determine social and environmental sustainability in the context of land use, density and design decisions, taken in the spatial planning process.

  13. A novel approach for absolute radar calibration: formulation and theoretical validation

    C. Merker

    2015-06-01

    Full Text Available The theoretical framework of a novel approach for absolute radar calibration is presented and its potential analysed by means of synthetic data to lay out a solid basis for future practical application. The method presents the advantage of an absolute calibration with respect to the directly measured reflectivity, without needing a previously calibrated reference device. It requires a setup comprising three radars: two devices oriented towards each other, measuring reflectivity along the same horizontal beam and operating within a strongly attenuated frequency range (e.g. K or X band, and one vertical reflectivity and drop size distribution (DSD profiler below this connecting line, which is to be calibrated. The absolute determination of the calibration factor is based on attenuation estimates. Using synthetic, smooth and geometrically idealised data, calibration is found to perform best using homogeneous precipitation events with rain rates high enough to ensure a distinct attenuation signal (reflectivity above ca. 30 dBZ. Furthermore, the choice of the interval width (in measuring range gates around the vertically pointing radar, needed for attenuation estimation, is found to have an impact on the calibration results. Further analysis is done by means of synthetic data with realistic, inhomogeneous precipitation fields taken from measurements. A calibration factor is calculated for each considered case using the presented method. Based on the distribution of the calculated calibration factors, the most probable value is determined by estimating the mode of a fitted shifted logarithmic normal distribution function. After filtering the data set with respect to rain rate and inhomogeneity and choosing an appropriate length of the considered attenuation path, the estimated uncertainty of the calibration factor is of the order of 1 to 11 %, depending on the chosen interval width. Considering stability and accuracy of the method, an interval of

  14. Theoretical study of γ-hexachlorocyclohexane and β-hexachlorocyclohexane isomers interaction with surface groups of activated carbon model.

    Enriquez-Victorero, Carlos; Hernández-Valdés, Daniel; Montero-Alejo, Ana Lilian; Durimel, Axelle; Gaspard, Sarra; Jáuregui-Haza, Ulises

    2014-06-01

    Activated carbon (AC) is employed in drinking water purification without almost any knowledge about the adsorption mechanism of persistent organic pollutants (POPs) onto it. Hexachlorocyclohexane (HCH) is an organochlorinated contaminant present in water and soils of banana crops production zones of the Caribbean. The most relevant isomers of HCH are γ-HCH and β-HCH, both with great environmental persistence. A theoretical study of the influence of AC surface groups (SGs) on HCH adsorption is done in order to help to understand the process and may lead to improve the AC selection process. A simplified AC model consisting of naphthalene with a functional group was used to assess the influence of SGs over the adsorption process. The Multiple Minima Hypersurface (MMH) methodology was employed to study γ-HCH and β-HCH interactions with different AC SGs (hydroxyl and carboxyl) under different hydration and pH conditions. The results obtained showed that association of HCH with SGs preferentially occurs between the axial protons of HCH and SG's oxygen atom, and the most favorable interactions occurring with charged SGs. An increase in carboxylic SGs content is proposed to enhance HCH adsorption onto AC under neutral pH conditions. Finally, this work presents an inexpensive computer aided methodology for preselecting activated carbon SGs content for the removal of a given compound. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Customized Assessment Group Initiative: A Complementary Approach to Students' Learning

    Akindayomi, Akinloye

    2015-01-01

    This study, conducted in a US setting, examines the importance of group dynamics that emphasize cooperative team building through the proposed grouping strategy called Customized Assessment Group Initiative (CAGI). CAGI is a student grouping strategy designed to operationalize the mutual accountability concept central to the definition of teams by…

  16. Cell death following BNCT: A theoretical approach based on Monte Carlo simulations

    Ballarini, F., E-mail: francesca.ballarini@pv.infn.it [University of Pavia, Department of Nuclear and Theoretical Physics, via Bassi 6, Pavia (Italy)] [INFN (National Institute of Nuclear Physics)-Sezione di Pavia, via Bassi 6, Pavia (Italy); Bakeine, J. [University of Pavia, Department of Nuclear and Theoretical Physics, via Bassi 6, Pavia (Italy); Bortolussi, S. [University of Pavia, Department of Nuclear and Theoretical Physics, via Bassi 6, Pavia (Italy)] [INFN (National Institute of Nuclear Physics)-Sezione di Pavia, via Bassi 6, Pavia (Italy); Bruschi, P. [University of Pavia, Department of Nuclear and Theoretical Physics, via Bassi 6, Pavia (Italy); Cansolino, L.; Clerici, A.M.; Ferrari, C. [University of Pavia, Department of Surgery, Experimental Surgery Laboratory, Pavia (Italy); Protti, N.; Stella, S. [University of Pavia, Department of Nuclear and Theoretical Physics, via Bassi 6, Pavia (Italy)] [INFN (National Institute of Nuclear Physics)-Sezione di Pavia, via Bassi 6, Pavia (Italy); Zonta, A.; Zonta, C. [University of Pavia, Department of Surgery, Experimental Surgery Laboratory, Pavia (Italy); Altieri, S. [University of Pavia, Department of Nuclear and Theoretical Physics, via Bassi 6, Pavia (Italy)] [INFN (National Institute of Nuclear Physics)-Sezione di Pavia, via Bassi 6, Pavia (Italy)

    2011-12-15

    In parallel to boron measurements and animal studies, investigations on radiation-induced cell death are also in progress in Pavia, with the aim of better characterisation of the effects of a BNCT treatment down to the cellular level. Such studies are being carried out not only experimentally but also theoretically, based on a mechanistic model and a Monte Carlo code. Such model assumes that: (1) only clustered DNA strand breaks can lead to chromosome aberrations; (2) only chromosome fragments within a certain threshold distance can undergo misrejoining; (3) the so-called 'lethal aberrations' (dicentrics, rings and large deletions) lead to cell death. After applying the model to normal cells exposed to monochromatic fields of different radiation types, the irradiation section of the code was purposely extended to mimic the cell exposure to a mixed radiation field produced by the {sup 10}B(n,{alpha}) {sup 7}Li reaction, which gives rise to alpha particles and Li ions of short range and high biological effectiveness, and by the {sup 14}N(n,p){sup 14}C reaction, which produces 0.58 MeV protons. Very good agreement between model predictions and literature data was found for human and animal cells exposed to X- or gamma-rays, protons and alpha particles, thus allowing to validate the model for cell death induced by monochromatic radiation fields. The model predictions showed good agreement also with experimental data obtained by our group exposing DHD cells to thermal neutrons in the TRIGA Mark II reactor of University of Pavia; this allowed to validate the model also for a BNCT exposure scenario, providing a useful predictive tool to bridge the gap between irradiation and cell death.

  17. Abnormalities of functional brain networks in pathological gambling: a graph-theoretical approach

    Tschernegg, Melanie; Crone, Julia S.; Eigenberger, Tina; Schwartenbeck, Philipp; Fauth-Bühler, Mira; Lemènager, Tagrid; Mann, Karl; Thon, Natasha; Wurst, Friedrich M.; Kronbichler, Martin

    2013-01-01

    Functional neuroimaging studies of pathological gambling (PG) demonstrate alterations in frontal and subcortical regions of the mesolimbic reward system. However, most investigations were performed using tasks involving reward processing or executive functions. Little is known about brain network abnormalities during task-free resting state in PG. In the present study, graph-theoretical methods were used to investigate network properties of resting state functional magnetic resonance imaging data in PG. We compared 19 patients with PG to 19 healthy controls (HCs) using the Graph Analysis Toolbox (GAT). None of the examined global metrics differed between groups. At the nodal level, pathological gambler showed a reduced clustering coefficient in the left paracingulate cortex and the left juxtapositional lobe (supplementary motor area, SMA), reduced local efficiency in the left SMA, as well as an increased node betweenness for the left and right paracingulate cortex and the left SMA. At an uncorrected threshold level, the node betweenness in the left inferior frontal gyrus was decreased and increased in the caudate. Additionally, increased functional connectivity between fronto-striatal regions and within frontal regions has also been found for the gambling patients. These findings suggest that regions associated with the reward system demonstrate reduced segregation but enhanced integration while regions associated with executive functions demonstrate reduced integration. The present study makes evident that PG is also associated with abnormalities in the topological network structure of the brain during rest. Since alterations in PG cannot be explained by direct effects of abused substances on the brain, these findings will be of relevance for understanding functional connectivity in other addictive disorders. PMID:24098282

  18. Abnormalities of Functional Brain Networks in Pathological Gambling: A Graph-Theoretical Approach

    Melanie eTschernegg

    2013-09-01

    Full Text Available Functional neuroimaging studies of pathological gambling demonstrate alterations in frontal and subcortical regions of the mesolimbic reward system. However, most investigations were performed using tasks involving reward processing or executive functions. Little is known about brain network abnormalities during task-free resting state in pathological gambling. In the present study, graph-theoretical methods were used to investigate network properties of resting state functional MRI data in pathological gambling. We compared 19 patients with pathological gambling to 19 healthy controls using the Graph Analysis Toolbox (GAT. None of the examined global metrics differed between groups. At the nodal level, pathological gambler showed a reduced clustering coefficient in the left paracingulate cortex and the left juxtapositional lobe (SMA, reduced local efficiency in the left SMA, as well as an increased node betweenness for the left and right paracingulate cortex and the left SMA. At an uncorrected threshold level, the node betweenness in the left inferior frontal gyrus was decreased and increased in the caudate. Additionally, increased functional connectivity between fronto-striatal regions and within frontal regions has also been found for the gambling patients.These findings suggest that regions associated with the reward system demonstrate reduced segregation but enhanced integration while regions associated with executive functions demonstrate reduced integration. The present study makes evident that pathological gambling is also associated with abnormalities in the topological network structure of the brain during rest. Since alterations in pathological gambling cannot be explained by direct effects of abused substances on the brain, these findings will be of relevance for understanding functional connectivity in other addictive disorders.

  19. Theoretical aspects of pressure and solute denaturation of proteins: A Kirkwood-buff-theory approach

    Ben-Naim, Arieh

    2012-12-01

    A new approach to the problem of pressure-denaturation (PD) and solute-denaturation (SD) of proteins is presented. The problem is formulated in terms of Le Chatelier principle, and a solution is sought in terms of the Kirkwood-Buff theory of solutions. It is found that both problems have one factor in common; the excluded volumes of the folded and the unfolded forms with respect to the solvent molecules. It is shown that solvent-induced effects operating on hydrophilic groups along the protein are probably the main reason for PD. On the other hand, the SD depends on the preferential solvation of the folded and the unfolded forms with respect to solvent and co-solvent molecules.

  20. Exploring SiSn as a performance enhancing semiconductor: A theoretical and experimental approach

    Hussain, Aftab M.; Singh, Nirpendra; Fahad, Hossain M.; Rader, Kelly; Schwingenschlö gl, Udo; Hussain, Muhammad Mustafa

    2014-01-01

    We present a novel semiconducting alloy, silicon-tin (SiSn), as channel material for complementary metal oxide semiconductor (CMOS) circuit applications. The material has been studied theoretically using first principles analysis as well

  1. Quantifying multi-dimensional functional trait spaces of trees: empirical versus theoretical approaches

    Ogle, K.; Fell, M.; Barber, J. J.

    2016-12-01

    Empirical, field studies of plant functional traits have revealed important trade-offs among pairs or triplets of traits, such as the leaf (LES) and wood (WES) economics spectra. Trade-offs include correlations between leaf longevity (LL) vs specific leaf area (SLA), LL vs mass-specific leaf respiration rate (RmL), SLA vs RmL, and resistance to breakage vs wood density. Ordination analyses (e.g., PCA) show groupings of traits that tend to align with different life-history strategies or taxonomic groups. It is unclear, however, what underlies such trade-offs and emergent spectra. Do they arise from inherent physiological constraints on growth, or are they more reflective of environmental filtering? The relative importance of these mechanisms has implications for predicting biogeochemical cycling, which is influenced by trait distributions of the plant community. We address this question using an individual-based model of tree growth (ACGCA) to quantify the theoretical trait space of trees that emerges from physiological constraints. ACGCA's inputs include 32 physiological, anatomical, and allometric traits, many of which are related to the LES and WES. We fit ACGCA to 1.6 million USFS FIA observations of tree diameters and heights to obtain vectors of trait values that produce realistic growth, and we explored the structure of this trait space. No notable correlations emerged among the 496 trait pairs, but stepwise regressions revealed complicated multi-variate structure: e.g., relationships between pairs of traits (e.g., RmL and SLA) are governed by other traits (e.g., LL, radiation-use efficiency [RUE]). We also simulated growth under various canopy gap scenarios that impose varying degrees of environmental filtering to explore the multi-dimensional trait space (hypervolume) of trees that died vs survived. The centroid and volume of the hypervolumes differed among dead and live trees, especially under gap conditions leading to low mortality. Traits most predictive

  2. New Perspectives on the Brain Lesion Approach - Implications for Theoretical Models of Human Memory.

    Irish, Muireann; van Kesteren, Marlieke T R

    2018-03-15

    Human lesion studies represent the cornerstone of modern day neuropsychology and provide an important adjunct to functional neuroimaging methods. The study of human lesion groups with damage to distinct regions of the brain permits the identification of underlying mechanisms and structures not only associated with, but essential for, complex cognitive processes. Here, we consider a recent review by McCormick et al., 2018 in which the power of the lesion model approach is elegantly presented with respect to a host of sophisticated cognitive endeavors, including autobiographical memory, future thinking, spatial navigation, and decision-making. By comparing profiles of loss and sparing in hippocampal (HC) and ventromedial prefrontal cortex (vmPFC) lesion groups, the authors provide new insights into the underlying neuroarchitecture of these diverse cognitive functions. Building on this framework, we consider how vmPFC and HC degeneration, in the context of large-scale network dysfunction in dementia, impacts discrete facets of memory and social cognition. Notably, we find remarkable concordance between the available evidence in dementia and that of the HC and vmPFC lesion literature. We further assess the role of the prefrontal cortex in modulating aspects of spatial navigation and discuss the role of schema-related processing in the service of memory more broadly. Far from being obsolete, we contend that human lesion work occupies a crucial position in cognitive neuroscience and offers an array of exciting areas for future study within this field. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Achieving behaviour change for detection of Lynch syndrome using the Theoretical Domains Framework Implementation (TDFI) approach: a study protocol.

    Taylor, Natalie; Long, Janet C; Debono, Deborah; Williams, Rachel; Salisbury, Elizabeth; O'Neill, Sharron; Eykman, Elizabeth; Braithwaite, Jeffrey; Chin, Melvin

    2016-03-12

    Lynch syndrome is an inherited disorder associated with a range of cancers, and found in 2-5 % of colorectal cancers. Lynch syndrome is diagnosed through a combination of significant family and clinical history and pathology. The definitive diagnostic germline test requires formal patient consent after genetic counselling. If diagnosed early, carriers of Lynch syndrome can undergo increased surveillance for cancers, which in turn can prevent late stage cancers, optimise treatment and decrease mortality for themselves and their relatives. However, over the past decade, international studies have reported that only a small proportion of individuals with suspected Lynch syndrome were referred for genetic consultation and possible genetic testing. The aim of this project is to use behaviour change theory and implementation science approaches to increase the number and speed of healthcare professional referrals of colorectal cancer patients with a high-likelihood risk of Lynch syndrome to appropriate genetic counselling services. The six-step Theoretical Domains Framework Implementation (TDFI) approach will be used at two large, metropolitan hospitals treating colorectal cancer patients. Steps are: 1) form local multidisciplinary teams to map current referral processes; 2) identify target behaviours that may lead to increased referrals using discussion supported by a retrospective audit; 3) identify barriers to those behaviours using the validated Influences on Patient Safety Behaviours Questionnaire and TDFI guided focus groups; 4) co-design interventions to address barriers using focus groups; 5) co-implement interventions; and 6) evaluate intervention impact. Chi square analysis will be used to test the difference in the proportion of high-likelihood risk Lynch syndrome patients being referred for genetic testing before and after intervention implementation. A paired t-test will be used to assess the mean time from the pathology test results to referral for high

  4. Aperture Array Photonic Metamaterials: Theoretical approaches, numerical techniques and a novel application

    Lansey, Eli

    Optical or photonic metamaterials that operate in the infrared and visible frequency regimes show tremendous promise for solving problems in renewable energy, infrared imaging, and telecommunications. However, many of the theoretical and simulation techniques used at lower frequencies are not applicable to this higher-frequency regime. Furthermore, technological and financial limitations of photonic metamaterial fabrication increases the importance of reliable theoretical models and computational techniques for predicting the optical response of photonic metamaterials. This thesis focuses on aperture array metamaterials. That is, a rectangular, circular, or other shaped cavity or hole embedded in, or penetrating through a metal film. The research in the first portion of this dissertation reflects our interest in developing a fundamental, theoretical understanding of the behavior of light's interaction with these aperture arrays, specifically regarding enhanced optical transmission. We develop an approximate boundary condition for metals at optical frequencies, and a comprehensive, analytical explanation of the physics underlying this effect. These theoretical analyses are augmented by computational techniques in the second portion of this thesis, used both for verification of the theoretical work, and solving more complicated structures. Finally, the last portion of this thesis discusses the results from designing, fabricating and characterizing a light-splitting metamaterial.

  5. Breaking the theoretical scaling limit for predicting quasiparticle energies: the stochastic GW approach.

    Neuhauser, Daniel; Gao, Yi; Arntsen, Christopher; Karshenas, Cyrus; Rabani, Eran; Baer, Roi

    2014-08-15

    We develop a formalism to calculate the quasiparticle energy within the GW many-body perturbation correction to the density functional theory. The occupied and virtual orbitals of the Kohn-Sham Hamiltonian are replaced by stochastic orbitals used to evaluate the Green function G, the polarization potential W, and, thereby, the GW self-energy. The stochastic GW (sGW) formalism relies on novel theoretical concepts such as stochastic time-dependent Hartree propagation, stochastic matrix compression, and spatial or temporal stochastic decoupling techniques. Beyond the theoretical interest, the formalism enables linear scaling GW calculations breaking the theoretical scaling limit for GW as well as circumventing the need for energy cutoff approximations. We illustrate the method for silicon nanocrystals of varying sizes with N_{e}>3000 electrons.

  6. Field theoretical approach to proton-nucleus reactions. I - One step inelastic scattering

    Eiras, A.; Kodama, T.; Nemes, M.C.

    1988-01-01

    In this work we obtain a closed form expression to the double differential cross section for one step proton-nucleus reaction within a field theoretical framework. Energy and momentum conservation as well as nuclear structure effects are consistently taken into account within the field theoretical eikonal approximation. In our formulation the kinematics of such reaction is not dominated by the free nucleon-nucleon cross section but a new factor which we call relativistic differential cross section in a Born Approximation. (author) [pt

  7. A short course in quantum information theory. An approach from theoretical physics

    Diosi, L.

    2007-01-01

    This short and concise primer takes the vantage point of theoretical physics and the unity of physics. It sets out to strip the burgeoning field of quantum information science to its basics by linking it to universal concepts in physics. An extensive lecture rather than a comprehensive textbook, this volume is based on courses delivered over several years to advanced undergraduate and beginning graduate students, but essentially it addresses anyone with a working knowledge of basic quantum physics. Readers will find these lectures a most adequate entry point for theoretical studies in this field. (orig.)

  8. Improving Student Group Marketing Presentations: A Modified Pecha Kucha Approach

    Oliver, Jason; Kowalczyk, Christine

    2013-01-01

    Student presentations can often seem like a formality rather than a lesson in representing oneself or group in a professional manner. To improve the quality of group presentations, the authors modified the popular presentation style of Pecha Kucha (20 slides, 20 seconds per slide) for marketing courses to help students prepare and deliver…

  9. A Psychoeducational Group Approach for Individuals Recovering from Anorexia Nervosa.

    Kapp, Lisa

    Although in-depth, long-term group psychotherapy is a beneficial therapeutic experience for adolescent females suffering from anorexia nervosa, these clients are notoriously resistant to treatment and to long-term, open-ended group settings. This dissidence may stem from a motivational deficiency toward changing their eating patterns and…

  10. Quantitative Approaches to Group Research: Suggestions for Best Practices

    McCarthy, Christopher J.; Whittaker, Tiffany A.; Boyle, Lauren H.; Eyal, Maytal

    2017-01-01

    Rigorous scholarship is essential to the continued growth of group work, yet the unique nature of this counseling specialty poses challenges for quantitative researchers. The purpose of this proposal is to overview unique challenges to quantitative research with groups in the counseling field, including difficulty in obtaining large sample sizes…

  11. Multiple Family Group Therapy: An Interpersonal/Postmodern Approach.

    Thorngren, Jill M.; Kleist, David M.

    2002-01-01

    Multiple Family Group Therapy has been identified as a viable treatment model for a variety of client populations. A combination of family systems theories and therapeutic group factors provide the opportunity to explore multiple levels of intrapersonal and interpersonal relationships between families. This article depicts a Multiple Family Group…

  12. Group Work in Schools: A Process Consultation Approach

    Farouk, Shaalan

    2004-01-01

    This paper provides a description of how an educational psychologist can consult with groups of teachers mostly in relation to their work with pupils who display emotional behavioural difficulties. The paper includes a review of the work on group consultation in schools, followed by a description of process consultation (Schein, 1988 ) and how the…

  13. Group size, grooming and fission in primates: a modeling approach based on group structure.

    Sueur, Cédric; Deneubourg, Jean-Louis; Petit, Odile; Couzin, Iain D

    2011-03-21

    In social animals, fission is a common mode of group proliferation and dispersion and may be affected by genetic or other social factors. Sociality implies preserving relationships between group members. An increase in group size and/or in competition for food within the group can result in decrease certain social interactions between members, and the group may split irreversibly as a consequence. One individual may try to maintain bonds with a maximum of group members in order to keep group cohesion, i.e. proximity and stable relationships. However, this strategy needs time and time is often limited. In addition, previous studies have shown that whatever the group size, an individual interacts only with certain grooming partners. There, we develop a computational model to assess how dynamics of group cohesion are related to group size and to the structure of grooming relationships. Groups' sizes after simulated fission are compared to observed sizes of 40 groups of primates. Results showed that the relationship between grooming time and group size is dependent on how each individual attributes grooming time to its social partners, i.e. grooming a few number of preferred partners or grooming equally or not all partners. The number of partners seemed to be more important for the group cohesion than the grooming time itself. This structural constraint has important consequences on group sociality, as it gives the possibility of competition for grooming partners, attraction for high-ranking individuals as found in primates' groups. It could, however, also have implications when considering the cognitive capacities of primates. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. A Survey of Game Theoretic Approaches to Modelling Decision-Making in Information Warfare Scenarios

    Kathryn Merrick

    2016-07-01

    Full Text Available Our increasing dependence on information technologies and autonomous systems has escalated international concern for information- and cyber-security in the face of politically, socially and religiously motivated cyber-attacks. Information warfare tactics that interfere with the flow of information can challenge the survival of individuals and groups. It is increasingly important that both humans and machines can make decisions that ensure the trustworthiness of information, communication and autonomous systems. Subsequently, an important research direction is concerned with modelling decision-making processes. One approach to this involves modelling decision-making scenarios as games using game theory. This paper presents a survey of information warfare literature, with the purpose of identifying games that model different types of information warfare operations. Our contribution is a systematic identification and classification of information warfare games, as a basis for modelling decision-making by humans and machines in such scenarios. We also present a taxonomy of games that map to information warfare and cyber crime problems as a precursor to future research on decision-making in such scenarios. We identify and discuss open research questions including the role of behavioural game theory in modelling human decision making and the role of machine decision-making in information warfare scenarios.

  15. A New Theoretical Approach to Postsecondary Student Disability: Disability-Diversity (Dis)Connect Model

    Aquino, Katherine C.

    2016-01-01

    Disability is often viewed as an obstacle to postsecondary inclusion, but not a characteristic of student diversity. Additionally, current theoretical frameworks isolate disability from other student diversity characteristics. In response, a new conceptual framework, the Disability-Diversity (Dis)Connect Model (DDDM), was created to address…

  16. Studies of the tautomeric equilibrium of 1,3-thiazolidine-2-thione: Theoretical and experimental approaches

    Abbehausen, Camilla; Paiva, Raphael E.F. de [Institute of Chemistry, University of Campinas - UNICAMP, P.O. Box 6154, 13083-970 Campinas, SP (Brazil); Formiga, Andre L.B., E-mail: formiga@iqm.unicamp.br [Institute of Chemistry, University of Campinas - UNICAMP, P.O. Box 6154, 13083-970 Campinas, SP (Brazil); Corbi, Pedro P. [Institute of Chemistry, University of Campinas - UNICAMP, P.O. Box 6154, 13083-970 Campinas, SP (Brazil)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer Tautomeric equilibrium in solution. Black-Right-Pointing-Pointer Spectroscopic and theoretical studies. Black-Right-Pointing-Pointer UV-Vis theoretical and experimental spectra. Black-Right-Pointing-Pointer {sup 1}H NMR theoretical and experimental spectra. -- Abstract: The tautomeric equilibrium of the thione/thiol forms of 1,3-thiazolidine-2-thione was studied by nuclear magnetic resonance, infrared and ultraviolet-visible spectroscopies. Density functional theory was used to support the experimental data and indicates the predominance of the thione tautomer in the solid state, being in agreement with previously reported crystallographic data. In solution, the tautomeric equilibrium was evaluated using {sup 1}H NMR at different temperatures in four deuterated solvents acetonitrile, dimethylsulfoxide, chloroform and methanol. The equilibrium constants, K = (thiol)/(thione), and free Gibbs energies were obtained by integration of N bonded hydrogen signals at each temperature for each solvent, excluding methanol. The endothermic tautomerization is entropy-driven and the combined effect of solvent and temperature can be used to achieve almost 50% thiol concentrations in solution. The nature of the electronic transitions was investigated theoretically and the assignment of the bands was made using time-dependent DFT as well as the influence of solvent on the energy of the most important bands of the spectra.

  17. A theoretical perspective of the nature of hydrogen-bond types - the atoms in molecules approach

    Pandiyan, B. V.; Kolandaivel, P.; Deepa, Palanisamy

    2014-01-01

    Roč. 112, č. 12 (2014), s. 1609-1623 ISSN 0026-8976 Institutional support: RVO:61388963 Keywords : hydrogen bond * proton affinity * deprotanation enthalpy * atoms in molecules * chemical shift Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.720, year: 2014

  18. A Dialectical Approach to Theoretical Integration in Developmental-Contextual Identity Research

    Seaman, Jayson; Sharp, Erin Hiley; Coppens, Andrew D.

    2017-01-01

    Future advances in identity research will depend on integration across major theoretical traditions. Developmental-contextualism has established essential criteria to guide this effort, including specifying the context of identity development, its timing over the life course, and its content. This article assesses 4 major traditions of identity…

  19. Between altruism and narcissism: An action theoretical approach of personal homepages devoted to existential meaning

    Hijmans, E.J.S.; Selm, M. van

    2002-01-01

    This article aims to examine existential meaning constructions from an action theoretical perspective in a specific Internet environment: the personal homepage. Personal homepages are on-line multi-media documents addressing the question Who am I? Authors of personal homepages provide information on

  20. A Holistic Theoretical Approach to Intellectual Disability: Going beyond the Four Current Perspectives

    Schalock, Robert L.; Luckasson, Ruth; Tassé, Marc J.; Verdugo, Miguel Angel

    2018-01-01

    This article describes a holistic theoretical framework that can be used to explain intellectual disability (ID) and organize relevant information into a usable roadmap to guide understanding and application. Developing the framework involved analyzing the four current perspectives on ID and synthesizing this information into a holistic…

  1. A decision-theoretic approach to collaboration: Principal description methods and efficient heuristic approximations

    Oliehoek, F.A.; Visser, A.; Babuška, R.; Groen, F.C.A

    2010-01-01

    This chapter gives an overview of the state of the art in decision-theoretic models to describe cooperation between multiple agents in a dynamic environment. Making (near-) optimal decisions in such settings gets harder when the number of agents grows or the uncertainty about the environment

  2. On the information-theoretic approach to G\\"odel's incompleteness theorem

    D'Abramo, Germano

    2002-01-01

    In this paper we briefly review and analyze three published proofs of Chaitin's theorem, the celebrated information-theoretic version of G\\"odel's incompleteness theorem. Then, we discuss our main perplexity concerning a key step common to all these demonstrations.

  3. Theoretical study of molecular vibrations in electron momentum spectroscopy experiments on furan: An analytical versus a molecular dynamical approach

    Morini, Filippo; Deleuze, Michael S.; Watanabe, Noboru; Takahashi, Masahiko

    2015-01-01

    The influence of thermally induced nuclear dynamics (molecular vibrations) in the initial electronic ground state on the valence orbital momentum profiles of furan has been theoretically investigated using two different approaches. The first of these approaches employs the principles of Born-Oppenheimer molecular dynamics, whereas the so-called harmonic analytical quantum mechanical approach resorts to an analytical decomposition of contributions arising from quantized harmonic vibrational eigenstates. In spite of their intrinsic differences, the two approaches enable consistent insights into the electron momentum distributions inferred from new measurements employing electron momentum spectroscopy and an electron impact energy of 1.2 keV. Both approaches point out in particular an appreciable influence of a few specific molecular vibrations of A 1 symmetry on the 9a 1 momentum profile, which can be unravelled from considerations on the symmetry characteristics of orbitals and their energy spacing

  4. THEORETICAL AND METHODOLOGICAL APPROACHES TO THE STUDY OF THE IMPACT OF INFORMATION TECHNOLOGY ON SOCIAL CONNECTIONS AMONG YOUTH

    Sofia Alexandrovna Zverkova

    2015-11-01

    Full Text Available The urgency is due to the virtualization of communication in modern society, especially among young people, affecting social relations and social support services. Stressed the need for a more in-depth study of network virtualization of social relations of society, due to the ambiguous consequences of this phenomenon among the youth.Purpose. Analyze classic and contemporary theoretical and methodological approaches to the study of social ties and social support in terms of technological progress.Results. The article presents a sociological analysis of theoretical and methodological approaches to the study of problems of interaction and social support among youth through strong and weak social ties in cyberspace and in the real world.Practical implications. The analysis gives the opportunity for a wide range of examining social relations in various fields of sociology, such as sociology of youth, sociology of communications.

  5. The current status of theoretically based approaches to the prediction of the critical heat flux in flow boiling

    Weisman, J.

    1991-01-01

    This paper reports on the phenomena governing the critical heat flux in flow boiling. Inducts which vary with the flow pattern. Separate models are needed for dryout in annular flow, wall overheating in plug or slug flow and formation of a vapor blanket in dispersed flow. The major theories and their current status are described for the annular and dispersed regions. The need for development of the theoretical approach in the plug and slug flow region is indicated

  6. Theoretical analysis of two ACO approaches for the traveling salesman problem

    Kötzing, Timo; Neumann, Frank; Röglin, Heiko

    2012-01-01

    Bioinspired algorithms, such as evolutionary algorithms and ant colony optimization, are widely used for different combinatorial optimization problems. These algorithms rely heavily on the use of randomness and are hard to understand from a theoretical point of view. This paper contributes...... to the theoretical analysis of ant colony optimization and studies this type of algorithm on one of the most prominent combinatorial optimization problems, namely the traveling salesperson problem (TSP). We present a new construction graph and show that it has a stronger local property than one commonly used...... for constructing solutions of the TSP. The rigorous runtime analysis for two ant colony optimization algorithms, based on these two construction procedures, shows that they lead to good approximation in expected polynomial time on random instances. Furthermore, we point out in which situations our algorithms get...

  7. ON THE APPLICATION OF PARTIAL BARRIERS FOR SPINNING MACHINE NOISE CONTROL: A THEORETICAL AND EXPERIMENTAL APPROACH

    M. R. Monazzam, A. Nezafat

    2007-04-01

    Full Text Available Noise is one of the most serious challenges in modern community. In some specific industries, according to the nature of process, this challenge is more threatening. This paper describes a means of noise control for spinning machine based on experimental measurements. Also advantages and disadvantages of the control procedure are added. Different factors which may affect the performance of the barrier in this situation are also mentioned. To provide a good estimation of the control measure, a theoretical formula is also described and it is compared with the field data. Good agreement between the results of filed measurements and theoretical presented model was achieved. No obvious noise reduction was seen by partial indoor barriers in low absorbent enclosed spaces, since the reflection from multiple hard surfaces is the main dominated factor in the tested environment. At the end, the situation of the environment and standards, which are necessary in attaining the ideal results, are explained.

  8. Exploring SiSn as a performance enhancing semiconductor: A theoretical and experimental approach

    Hussain, Aftab M.

    2014-12-14

    We present a novel semiconducting alloy, silicon-tin (SiSn), as channel material for complementary metal oxide semiconductor (CMOS) circuit applications. The material has been studied theoretically using first principles analysis as well as experimentally by fabricating MOSFETs. Our study suggests that the alloy offers interesting possibilities in the realm of silicon band gap tuning. We have explored diffusion of tin (Sn) into the industry\\'s most widely used substrate, silicon (100), as it is the most cost effective, scalable and CMOS compatible way of obtaining SiSn. Our theoretical model predicts a higher mobility for p-channel SiSn MOSFETs, due to a lower effective mass of the holes, which has been experimentally validated using the fabricated MOSFETs. We report an increase of 13.6% in the average field effect hole mobility for SiSn devices compared to silicon control devices.

  9. A novel game theoretic approach for modeling competitive information diffusion in social networks with heterogeneous nodes

    Agha Mohammad Ali Kermani, Mehrdad; Fatemi Ardestani, Seyed Farshad; Aliahmadi, Alireza; Barzinpour, Farnaz

    2017-01-01

    Influence maximization deals with identification of the most influential nodes in a social network given an influence model. In this paper, a game theoretic framework is developed that models a competitive influence maximization problem. A novel competitive influence model is additionally proposed that incorporates user heterogeneity, message content, and network structure. The proposed game-theoretic model is solved using Nash Equilibrium in a real-world dataset. It is shown that none of the well-known strategies are stable and at least one player has the incentive to deviate from the proposed strategy. Moreover, violation of Nash equilibrium strategy by each player leads to their reduced payoff. Contrary to previous works, our results demonstrate that graph topology, as well as the nodes' sociability and initial tendency measures have an effect on the determination of the influential node in the network.

  10. A theoretical approach to dual practice regulations in the health sector.

    González, Paula; Macho-Stadler, Inés

    2013-01-01

    Internationally, there is wide cross-country heterogeneity in government responses to dual practice in the health sector. This paper provides a uniform theoretical framework to analyze and compare some of the most common regulations. We focus on three interventions: banning dual practice, offering rewarding contracts to public physicians, and limiting dual practice (including both limits to private earnings of dual providers and limits to involvement in private activities). An ancillary objective of the paper is to investigate whether regulations that are optimal for developed countries are adequate for developing countries as well. Our results offer theoretical support for the desirability of different regulations in different economic environments. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Black hole state counting in loop quantum gravity: a number-theoretical approach.

    Agulló, Iván; Barbero G, J Fernando; Díaz-Polo, Jacobo; Fernández-Borja, Enrique; Villaseñor, Eduardo J S

    2008-05-30

    We give an efficient method, combining number-theoretic and combinatorial ideas, to exactly compute black hole entropy in the framework of loop quantum gravity. Along the way we provide a complete characterization of the relevant sector of the spectrum of the area operator, including degeneracies, and explicitly determine the number of solutions to the projection constraint. We use a computer implementation of the proposed algorithm to confirm and extend previous results on the detailed structure of the black hole degeneracy spectrum.

  12. What happens in recessions? A value-theoretic approach to Liquidity Preference

    Freeman, Alan

    1998-01-01

    This paper develops the paper entitled ‘‘Time, the Value of Money and the Quantification of Value’ which was presented at the conference of the Middle East Technical University in September 1998. It presents the case for a value-theoretic treatment of liquidity preference in axiomatic form, based on a temporal analysis. It discusses why temporal analysis is universally excluded from economic discourse. It argues that economic thought is divided not by the schism between classical and marg...

  13. Towards a comprehensive theory for He II: II. A temperature-dependent field-theoretic approach

    Chela-Flores, J.; Ghassib, H.B.

    1982-09-01

    New experimental aspects of He II are used as a guide towards a comprehensive theory in which non-zero temperature U(1) and SU(2) gauge fields are incorporated into a gauge hierarchy of effective Lagrangians. We conjecture that an SU(n) gauge-theoretic description of the superfluidity of 4 He may be obtained in the limit n→infinity. We indicate, however, how experiments may be understood in the zeroth, first and second order of the hierarchy. (author)

  14. Defining and measuring blood donor altruism: a theoretical approach from biology, economics and psychology.

    Evans, R; Ferguson, E

    2014-02-01

    While blood donation is traditionally described as a behaviour motivated by pure altruism, the assessment of altruism in the blood donation literature has not been theoretically informed. Drawing on theories of altruism from psychology, economics and evolutionary biology, it is argued that a theoretically derived psychometric assessment of altruism is needed. Such a measure is developed in this study that can be used to help inform both our understanding of the altruistic motives of blood donors and recruitment intervention strategies. A cross-sectional survey (N = 414), with a 1-month behavioural follow-up (time 2, N = 77), was designed to assess theoretically derived constructs from psychological, economic and evolutionary biological theories of altruism. Theory of planned behaviour (TPB) variables and co-operation were also assessed at time 1 and a measure of behavioural co-operation at time 2. Five theoretical dimensions (impure altruism, kinship, self-regarding motives, reluctant altruism and egalitarian warm glow) of altruism were identified through factor analyses. These five altruistic motives differentiated blood donors from non-donors (donors scored higher on impure altruism and reluctant altruism), showed incremental validity over TPB constructs to predict donor intention and predicted future co-operative behaviour. These findings show that altruism in the context of blood donation is multifaceted and complex and, does not reflect pure altruism. This has implication for recruitment campaigns that focus solely on pure altruism. © 2013 The Authors. Vox Sanguinis published by John Wiley & Sons Ltd. on behalf of International Society of Blood Transfusion.

  15. THEORETICAL APPROACHES TO ASSESS THE IMPACT OF ADVERTISING ON CONSUMERS AND MARKET COMPETITION

    Maryna SOBOLIEVA

    2016-07-01

    Full Text Available In the article we examine theoretical perspectives on the impact of advertising on consumer behavior, entry barriers in the industry, the structure of the industry, the competitive behavior of firms and market power; systemic structure of the research of advertising impact on consumer behavior; analyze the main results of empirical studies of the effects of advertising on the competitive relationship in the market.

  16. THEORETICAL APPROACHES TO ASSESS THE IMPACT OF ADVERTISING ON CONSUMERS AND MARKET COMPETITION

    Maryna SOBOLIEVA

    2016-07-01

    Full Text Available In the article we examine theoretical perspectives on the impact of advertising on consumer behavior, entry barriers in the industry, the structure of the industry, the competitive behavior of firms and market power; systemize structure of the research of advertising impact on consumer behavior; analyze the main results of empirical studies of the effects of advertising on the competitive relationship in the market.

  17. Something new: a new approach to correcting theoretical emitted intensities for absorption effects

    Willis, J.P.; Lachance, G.R.

    2002-01-01

    Full text: For monochromatic incident radiation of wavelength λ, absorption only (no enhancement), and ignoring such effects as the absorption edge jump ratio, the fluorescence yield, and the probability that a Kα line will be emitted instead of a Kβ line, a simplified view of the theoretical emitted intensity of a characteristic line of element >i= from a layer in a specimen is given by a familiar equation which involves mass absorption coefficients. While this equation allows for the calculation of the theoretical emitted intensity, it is cumbersome to use when trying to explain X-ray excitation in a step-wise manner. It is therefore proposed that the mass attenuation coefficients (μ iλ , and the sum of μ sλ ' + μ sλi '' , in the numerator and denominator of this equation be replaced by the product of two coefficients correcting for absorption, namely aN H aO. The advantages of using the proposed equation in the stepwise calculation of theoretical intensities (in a similar manner to Monte Carlo calculations) will be discussed. Copyright (2002) Australian X-ray Analytical Association Inc

  18. δ-Cut Decision-Theoretic Rough Set Approach: Model and Attribute Reductions

    Hengrong Ju

    2014-01-01

    Full Text Available Decision-theoretic rough set is a quite useful rough set by introducing the decision cost into probabilistic approximations of the target. However, Yao’s decision-theoretic rough set is based on the classical indiscernibility relation; such a relation may be too strict in many applications. To solve this problem, a δ-cut decision-theoretic rough set is proposed, which is based on the δ-cut quantitative indiscernibility relation. Furthermore, with respect to criterions of decision-monotonicity and cost decreasing, two different algorithms are designed to compute reducts, respectively. The comparisons between these two algorithms show us the following: (1 with respect to the original data set, the reducts based on decision-monotonicity criterion can generate more rules supported by the lower approximation region and less rules supported by the boundary region, and it follows that the uncertainty which comes from boundary region can be decreased; (2 with respect to the reducts based on decision-monotonicity criterion, the reducts based on cost minimum criterion can obtain the lowest decision costs and the largest approximation qualities. This study suggests potential application areas and new research trends concerning rough set theory.

  19. A Methodological Demonstration of Set-theoretical Approach to Social Media Maturity Models Using Necessary Condition Analysis

    Lasrado, Lester Allan; Vatrapu, Ravi; Andersen, Kim Normann

    2016-01-01

    Despite being widely accepted and applied across research domains, maturity models have been criticized for lacking academic rigor, especially methodologically rigorous and empirically grounded or tested maturity models are quite rare. Attempting to close this gap, we adopt a set-theoretic approach...... and evaluate some of arguments presented by previous conceptual focused social media maturity models....... by applying the Necessary Condition Analysis (NCA) technique to derive maturity stages and stage boundaries conditions. The ontology is to view stages (boundaries) in maturity models as a collection of necessary condition. Using social media maturity data, we demonstrate the strength of our approach...

  20. A model-based approach to operational event groups ranking

    Simic, Zdenko [European Commission Joint Research Centre, Petten (Netherlands). Inst. for Energy and Transport; Maqua, Michael [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Koeln (Germany); Wattrelos, Didier [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France)

    2014-04-15

    The operational experience (OE) feedback provides improvements in all industrial activities. Identification of the most important and valuable groups of events within accumulated experience is important in order to focus on a detailed investigation of events. The paper describes the new ranking method and compares it with three others. Methods have been described and applied to OE events utilised by nuclear power plants in France and Germany for twenty years. The results show that different ranking methods only roughly agree on which of the event groups are the most important ones. In the new ranking method the analytical hierarchy process is applied in order to assure consistent and comprehensive weighting determination for ranking indexes. The proposed method allows a transparent and flexible event groups ranking and identification of the most important OE for further more detailed investigation in order to complete the feedback. (orig.)

  1. Licit and illicit drugs: a group approach with teenagers

    Deborah Amaral Donnini; Darilene Rocha Cordeiro; Bruna Camargos de Lima; Selma Maria da Fonseca Viegas

    2017-01-01

    This work is an extension intervention arising from the results of an epidemiological cross-sectional study with 605 teenagers from 13 to 16 years old. The extension actions had as a method the group educational practice on licit and illicit drugs, with 2.012 teenagers from 22 municipal and state public schools of the urban region of Divinópolis, State of Minas Gerais, Brazil, from March 2015 to February 2016. It aimed to work with group educational practices on licit and illicit drugs in the...

  2. On Tradeoffs between Trust and Survivability using a Game Theoretic Approach

    2016-04-13

    given group protocol. That is, the entire system is penalized or rewarded regardless of which individual entity misbehaved or behaved, so that group...study the tradeoff between group trust and system survivability in the presence of misbehaving nodes and under resource constraints. Lastly, we...threshold. However, in this case, the system penalizes the misbehaving node by evicting it, ultimately eliminating any chance of participation in any group

  3. Strategic Approach to Group Anger Management with Incarcerated Murderers.

    Napolitano, Susan; Brown, Lillian G.

    1991-01-01

    Incarcerated male murderers manifested consistent changes in attitudes toward treatment efficacy and their culpability as function of participating in 12-week anger management groups. Four qualitatively different stages were evident during treatment as prisoners' resistive responses were actively encouraged: initial apathy, emerging interest in…

  4. Real-space renormalization group approach to driven diffusive systems

    Hanney, T [SUPA and School of Physics, University of Edinburgh, Mayfield Road, Edinburgh, EH9 3JZ (United Kingdom); Stinchcombe, R B [Theoretical Physics, 1 Keble Road, Oxford, OX1 3NP (United Kingdom)

    2006-11-24

    We introduce a real-space renormalization group procedure for driven diffusive systems which predicts both steady state and dynamic properties. We apply the method to the boundary driven asymmetric simple exclusion process and recover exact results for the steady state phase diagram, as well as the crossovers in the relaxation dynamics for each phase.

  5. Real-space renormalization group approach to driven diffusive systems

    Hanney, T; Stinchcombe, R B

    2006-01-01

    We introduce a real-space renormalization group procedure for driven diffusive systems which predicts both steady state and dynamic properties. We apply the method to the boundary driven asymmetric simple exclusion process and recover exact results for the steady state phase diagram, as well as the crossovers in the relaxation dynamics for each phase

  6. ANALYSIS OF THEORETICAL AND METHODOLOGICAL APPROACHES TO DESIGN OF ELECTRONIC TEXTBOOKS FOR STUDENTS OF HIGHER AGRICULTURAL EDUCATIONAL INSTITUTIONS

    Olena Yu. Balalaieva

    2017-06-01

    Full Text Available The article deals with theoretical and methodological approaches to the design of electronic textbook, in particular systems, competence, activity, personality oriented, technological one, that in complex reflect the general trends in the formation of a new educational paradigm, distinctive features of which lie in constructing the heuristic searching model of the learning process, focusing on developmental teaching, knowledge integration, skills development for the independent information search and processing, technification of the learning process. The approach in this study is used in a broad sense as a synthesis of the basic ideas, views, principles that determine the overall research strategy. The main provisions of modern approaches to design are not antagonistic, they should be applied in a complex, taking into account the advantages of each of them and leveling shortcomings for the development of optimal concept of electronic textbook. The model of electronic textbook designing and components of methodology for its using based on these approaches are described.

  7. Renormalization group approach to causal bulk viscous cosmological models

    Belinchon, J A; Harko, T; Mak, M K

    2002-01-01

    The renormalization group method is applied to the study of homogeneous and flat Friedmann-Robertson-Walker type universes, filled with a causal bulk viscous cosmological fluid. The starting point of the study is the consideration of the scaling properties of the gravitational field equations, the causal evolution equation of the bulk viscous pressure and the equations of state. The requirement of scale invariance imposes strong constraints on the temporal evolution of the bulk viscosity coefficient, temperature and relaxation time, thus leading to the possibility of obtaining the bulk viscosity coefficient-energy density dependence. For a cosmological model with bulk viscosity coefficient proportional to the Hubble parameter, we perform the analysis of the renormalization group flow around the scale-invariant fixed point, thereby obtaining the long-time behaviour of the scale factor

  8. Failure mode and effects analysis A fuzzy group MCDM approach

    A. Hadi-Vencheh

    2013-08-01

    Full Text Available In this paper, a new fuzzy group decision making (FGDM model based on alpha-level sets, is proposed to generate, more accurate fuzzy using, risk priority numbers (RPNs and ensure to be robust against the uncertainty. This model allows decision makers (DMs to evaluate FMEA risk factors using linguistic terms rather than precise numerical values, allows them to express their opinions independently. A case study is investigated using the proposed model to illustrate its applications in RPN assessment.

  9. Application of the Group Contribution Approach to Nafion Swelling

    Randová, A.; Bartovská, L.; Hovorka, Š.; Poloncarzová, M.; Kolská, Z.; Izák, Pavel

    2009-01-01

    Roč. 111, č. 4 (2009), s. 1745-1750 ISSN 0021-8995 R&D Projects: GA ČR GA104/08/0600; GA AV ČR IAA400720710 Institutional research plan: CEZ:AV0Z40720504 Keywords : group contribution method * structure-property relations * swelling Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.203, year: 2009

  10. Temperature renormalization group approach to spontaneous symmetry breaking

    Manesis, E.; Sakakibara, S.

    1985-01-01

    We apply renormalization group equations that describe the finite-temperature behavior of Green's functions to investigate thermal properties of spontaneous symmetry breaking. Specifically, in the O(N).O(N) symmetric model we study the change of symmetry breaking patterns with temperature, and show that there always exists the unbroken symmetry phase at high temperature, modifying the naive result of leading order in finite-temperature perturbation theory. (orig.)

  11. Approaching the theoretical capacitance of graphene through copper foam integrated three-dimensional graphene networks

    Dey, Ramendra Sundar; Hjuler, Hans Aage; Chi, Qijin

    2015-01-01

    We report a facile and low-cost approach for the preparation of all-in-one supercapacitor electrodes using copper foam (CuF) integrated three-dimensional (3D) reduced graphene oxide (rGO) networks. The binderfree 3DrGO@CuF electrodes are capable of delivering high specific capacitance approaching...

  12. On the design of a hierarchical SS7 network: A graph theoretical approach

    Krauss, Lutz; Rufa, Gerhard

    1994-04-01

    This contribution is concerned with the design of Signaling System No. 7 networks based on graph theoretical methods. A hierarchical network topology is derived by combining the advantage of the hierarchical network structure with the realization of node disjoint routes between nodes of the network. By using specific features of this topology, we develop an algorithm to construct circle-free routing data and to assure bidirectionality also in case of failure situations. The methods described are based on the requirements that the network topology, as well as the routing data, may be easily changed.

  13. A theoretical approach to sputtering due to molecular ion bombardment, 1

    Karashima, Shosuke; Ootoshi, Tsukuru; Kamiyama, Masahide; Kim, Pil-Hyon; Namba, Susumu.

    1981-01-01

    A shock wave model is proposed to explain theoretically the non-linear effects in sputtering phenomena by molecular ion bombardments. In this theory the sputtering processes are separated into two parts; one is due to linear effects and another is due to non-linear effects. The treatment of the linear parts is based on the statistical model by Schwarz and Helms concerning a broad range of atomic collision cascades. The non-linear parts are treated by the model of shock wave due to overlapping cascades, and useful equations to calculate the sputtering yields and the dynamical quantities in the system are derived. (author)

  14. Nonlocal approach to the analysis of the stress distribution in granular systems. I. Theoretical framework

    Kenkre, V. M.; Scott, J. E.; Pease, E. A.; Hurd, A. J.

    1998-05-01

    A theoretical framework for the analysis of the stress distribution in granular materials is presented. It makes use of a transformation of the vertical spatial coordinate into a formal time variable and the subsequent study of a generally non-Markoffian, i.e., memory-possessing (nonlocal) propagation equation. Previous treatments are obtained as particular cases corresponding to, respectively, wavelike and diffusive limits of the general evolution. Calculations are presented for stress propagation in bounded and unbounded media. They can be used to obtain desired features such as a prescribed stress distribution within the compact.

  15. Special course on modern theoretical and experimental approaches to turbulent flow structure and its modelling

    1987-08-01

    The large eddy concept in turbulent modeling and techniques for direct simulation are discussed. A review of turbulence modeling is presented along with physical and numerical aspects and applications. A closure model for turbulent flows is presented and routes to chaos by quasi-periodicity are discussed. Theoretical aspects of transition to turbulence by space/time intermittency are covered. The application to interpretation of experimental results of fractal dimensions and connection of spatial temporal chaos are reviewed. Simulation of hydrodynamic flow by using cellular automata is discussed.

  16. Wavelength shift in a whispering gallery microdisk due to bacterial sensing: A theoretical approach

    Hala Ghali

    2017-04-01

    Full Text Available Whispering gallery mode microcavities have recently been studied as a means to achieve real-time label-free detection of biological targets such as virus particles, specific DNA sequences, or proteins. Binding of a biomolecule to the surface of a microresonator will increase its path length, leading to a shift in the resonance frequency according to the reactive sensing principle. In this paper, we develop a theoretical expression that will link the reactive shift to the bacteria and microdisk parameters and help quantify the number of bacteria that bind to the surface of a 200μm-diameter silica microdisk. Keywords: Optical microdisk, Wavelength shift, Bacterial sensing

  17. Towards a comprehensive theory for He II: A temperature-dependent field-theoretic approach

    Ghassib, H.B.; Chela-Flores, J.

    1983-07-01

    New experimental aspects of He II, as well as recent developments in particle physics, are invoked to construct the rudiments of a comprehensive theory in which temperature-dependent U(1) and SU(2) gauge fields are incorporated into a hierarchy of effective Lagrangians. It is conjectured that an SU(n) gauge-theoretic description of superfluidity may be obtained in the limit n→infinity. However, it is outlined how experiments can be understood in the zeroth, first and second order of the hierarchy. (author)

  18. Algebraic and group treatments to nonlinear displaced number states and their nonclassicality features: A new approach

    Asili Firouzabadi, N; Tavassoly, M K; Faghihi, M J

    2015-01-01

    Recently, nonlinear displaced number states (NDNSs) have been manually introduced, in which the deformation function f(n) has been artificially added to the previously well-known displaced number states (DNSs). Indeed, just a simple comparison has been performed between the standard coherent state and nonlinear coherent state for the formation of NDNSs. In the present paper, after expressing enough physical motivation of our procedure, four distinct classes of NDNSs are presented by applying algebraic and group treatments. To achieve this purpose, by considering the DNSs and recalling the nonlinear coherent states formalism, the NDNSs are logically defined through an algebraic consideration. In addition, by using a particular class of Gilmore–Perelomov-type of SU(1, 1) and a class of SU(2) coherent states, the NDNSs are introduced via group-theoretical approach. Then, in order to examine the nonclassical behavior of these states, sub-Poissonian statistics by evaluating Mandel parameter and Wigner quasi-probability distribution function associated with the obtained NDNSs are discussed, in detail. (paper)

  19. An approach to correlate experimental and theoretical thermal conductivity of MWNT/PMMA polymer composites

    Verma, M; Patidar, D; Sharma, K B; Saxena, N S

    2015-01-01

    In this paper an effort is made to correlate temperature dependent effective thermal conductivity measured by experimental method to theoretical results obtained from different models. MWNT/PMMA polymer nanocomposites were prepared by solution casting method, with different wt% of MWNT (0, 0.05, 0.1, 0.2, 0.3, 0.5, 1, 5, 10 wt%) dispersed in the PMMA matrix. The effective thermal conductivity from 30 °C to 110 °C is measured by Hot Disk Thermal Constant Analyser, based on transient plane source technique. Experimental study reveals that effective thermal conductivity increases with increasing concentration of MWNT in PMMA and increases exponentially at high temperatures for high (5, 10) wt% samples. This behavior of effective thermal conductivity is explained in terms of the interactions between polymer–MWNT and MWNT–MWNT. Consequently these results were found to be in agreement with theoretical models such as Series, Parallel, Lewis/Neilson and empirical formula. The discrepancy found in Lewis/Neilson model at high temperature for high wt% of MWNT in PMMA is due to some change in values of parameters incorporated in the model. (paper)

  20. Theoretical approaches of online social network interventions and implications for behavioral change: a systematic review.

    Arguel, Amaël; Perez-Concha, Oscar; Li, Simon Y W; Lau, Annie Y S

    2018-02-01

    The aim of this review was to identify general theoretical frameworks used in online social network interventions for behavioral change. To address this research question, a PRISMA-compliant systematic review was conducted. A systematic review (PROSPERO registration number CRD42014007555) was conducted using 3 electronic databases (PsycINFO, Pubmed, and Embase). Four reviewers screened 1788 abstracts. 15 studies were selected according to the eligibility criteria. Randomized controlled trials and controlled studies were assessed using Cochrane Collaboration's "risk-of-bias" tool, and narrative synthesis. Five eligible articles used the social cognitive theory as a framework to develop interventions targeting behavioral change. Other theoretical frameworks were related to the dynamics of social networks, intention models, and community engagement theories. Only one of the studies selected in the review mentioned a well-known theory from the field of health psychology. Conclusions were that guidelines are lacking in the design of online social network interventions for behavioral change. Existing theories and models from health psychology that are traditionally used for in situ behavioral change should be considered when designing online social network interventions in a health care setting. © 2016 John Wiley & Sons, Ltd.

  1. Merging Theoretical Models and Therapy Approaches in the Context of Internet Gaming Disorder: A Personal Perspective

    Young, Kimberly S.; Brand, Matthias

    2017-01-01

    Although, it is not yet officially recognized as a clinical entity which is diagnosable, Internet Gaming Disorder (IGD) has been included in section III for further study in the DSM-5 by the American Psychiatric Association (APA, 2013). This is important because there is increasing evidence that people of all ages, in particular teens and young adults, are facing very real and sometimes very severe consequences in daily life resulting from an addictive use of online games. This article summarizes general aspects of IGD including diagnostic criteria and arguments for the classification as an addictive disorder including evidence from neurobiological studies. Based on previous theoretical considerations and empirical findings, this paper examines the use of one recently proposed model, the Interaction of Person-Affect-Cognition-Execution (I-PACE) model, for inspiring future research and for developing new treatment protocols for IGD. The I-PACE model is a theoretical framework that explains symptoms of Internet addiction by looking at interactions between predisposing factors, moderators, and mediators in combination with reduced executive functioning and diminished decision making. Finally, the paper discusses how current treatment protocols focusing on Cognitive-Behavioral Therapy for Internet addiction (CBT-IA) fit with the processes hypothesized in the I-PACE model. PMID:29104555

  2. A novel multi-stage direct contact membrane distillation module: Design, experimental and theoretical approaches

    Lee, Jung Gil

    2016-10-24

    An economic desalination system with a small scale and footprint for remote areas, which have a limited and inadequate water supply, insufficient water treatment and low infrastructure, is strongly demanded in the desalination markets. Here, a direct contact membrane distillation (DCMD) process has the simplest configuration and potentially the highest permeate flux among all of the possible MD processes. This process can also be easily instituted in a multi-stage manner for enhanced compactness, productivity, versatility and cost-effectiveness. In this study, an innovative, multi-stage, DCMD module under countercurrent-flow configuration is first designed and then investigate both theoretically and experimentally to identify its feasibility and operability for desalination application. Model predictions and measured data for mean permeate flux are compared and shown to be in good agreement. The effect of the number of module stages on the mean permeate flux, performance ratio and daily water production of the MDCMD system has been theoretically identified at inlet feed and permeate flow rates of 1.5 l/min and inlet feed and permeate temperatures of 70 °C and 25 °C, respectively. The daily water production of a three-stage DCMD module with a membrane area of 0.01 m2 at each stage is found to be 21.5 kg.

  3. A novel multi-stage direct contact membrane distillation module: Design, experimental and theoretical approaches.

    Lee, Jung-Gil; Kim, Woo-Seung; Choi, June-Seok; Ghaffour, Noreddine; Kim, Young-Deuk

    2016-12-15

    An economic desalination system with a small scale and footprint for remote areas, which have a limited and inadequate water supply, insufficient water treatment and low infrastructure, is strongly demanded in the desalination markets. Here, a direct contact membrane distillation (DCMD) process has the simplest configuration and potentially the highest permeate flux among all of the possible MD processes. This process can also be easily instituted in a multi-stage manner for enhanced compactness, productivity, versatility and cost-effectiveness. In this study, an innovative, multi-stage, DCMD module under countercurrent-flow configuration is first designed and then investigate both theoretically and experimentally to identify its feasibility and operability for desalination application. Model predictions and measured data for mean permeate flux are compared and shown to be in good agreement. The effect of the number of module stages on the mean permeate flux, performance ratio and daily water production of the MDCMD system has been theoretically identified at inlet feed and permeate flow rates of 1.5 l/min and inlet feed and permeate temperatures of 70 °C and 25 °C, respectively. The daily water production of a three-stage DCMD module with a membrane area of 0.01 m 2  at each stage is found to be 21.5 kg. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. A Game Theoretical Approach to Hacktivism: Is Attack Likelihood a Product of Risks and Payoffs?

    Bodford, Jessica E; Kwan, Virginia S Y

    2018-02-01

    The current study examines hacktivism (i.e., hacking to convey a moral, ethical, or social justice message) through a general game theoretic framework-that is, as a product of costs and benefits. Given the inherent risk of carrying out a hacktivist attack (e.g., legal action, imprisonment), it would be rational for the user to weigh these risks against perceived benefits of carrying out the attack. As such, we examined computer science students' estimations of risks, payoffs, and attack likelihood through a game theoretic design. Furthermore, this study aims at constructing a descriptive profile of potential hacktivists, exploring two predicted covariates of attack decision making, namely, peer prevalence of hacking and sex differences. Contrary to expectations, results suggest that participants' estimations of attack likelihood stemmed solely from expected payoffs, rather than subjective risks. Peer prevalence significantly predicted increased payoffs and attack likelihood, suggesting an underlying descriptive norm in social networks. Notably, we observed no sex differences in the decision to attack, nor in the factors predicting attack likelihood. Implications for policymakers and the understanding and prevention of hacktivism are discussed, as are the possible ramifications of widely communicated payoffs over potential risks in hacking communities.

  5. Merging Theoretical Models and Therapy Approaches in the Context of Internet Gaming Disorder: A Personal Perspective.

    Young, Kimberly S; Brand, Matthias

    2017-01-01

    Although, it is not yet officially recognized as a clinical entity which is diagnosable, Internet Gaming Disorder (IGD) has been included in section III for further study in the DSM-5 by the American Psychiatric Association (APA, 2013). This is important because there is increasing evidence that people of all ages, in particular teens and young adults, are facing very real and sometimes very severe consequences in daily life resulting from an addictive use of online games. This article summarizes general aspects of IGD including diagnostic criteria and arguments for the classification as an addictive disorder including evidence from neurobiological studies. Based on previous theoretical considerations and empirical findings, this paper examines the use of one recently proposed model, the Interaction of Person-Affect-Cognition-Execution (I-PACE) model, for inspiring future research and for developing new treatment protocols for IGD. The I-PACE model is a theoretical framework that explains symptoms of Internet addiction by looking at interactions between predisposing factors, moderators, and mediators in combination with reduced executive functioning and diminished decision making. Finally, the paper discusses how current treatment protocols focusing on Cognitive-Behavioral Therapy for Internet addiction (CBT-IA) fit with the processes hypothesized in the I-PACE model.

  6. Merging Theoretical Models and Therapy Approaches in the Context of Internet Gaming Disorder: A Personal Perspective

    Kimberly S. Young

    2017-10-01

    Full Text Available Although, it is not yet officially recognized as a clinical entity which is diagnosable, Internet Gaming Disorder (IGD has been included in section III for further study in the DSM-5 by the American Psychiatric Association (APA, 2013. This is important because there is increasing evidence that people of all ages, in particular teens and young adults, are facing very real and sometimes very severe consequences in daily life resulting from an addictive use of online games. This article summarizes general aspects of IGD including diagnostic criteria and arguments for the classification as an addictive disorder including evidence from neurobiological studies. Based on previous theoretical considerations and empirical findings, this paper examines the use of one recently proposed model, the Interaction of Person-Affect-Cognition-Execution (I-PACE model, for inspiring future research and for developing new treatment protocols for IGD. The I-PACE model is a theoretical framework that explains symptoms of Internet addiction by looking at interactions between predisposing factors, moderators, and mediators in combination with reduced executive functioning and diminished decision making. Finally, the paper discusses how current treatment protocols focusing on Cognitive-Behavioral Therapy for Internet addiction (CBT-IA fit with the processes hypothesized in the I-PACE model.

  7. Electronic properties of Fe charge transfer complexes – A combined experimental and theoretical approach

    Ferreira, Hendrik; Eschwege, Karel G. von; Conradie, Jeanet

    2016-01-01

    Highlights: • Experimental and computational study of Fe II -phen, -bpy & -tpy compleesx. • Close correlations between experimental redox and spectral, and computational data. • Computational methods fast-track DSSC research. - Abstract: Dye-sensitized solar cell technology holds huge potential in renewable electricity generation of the future. Due to demand urgency, ways need to be explored to reduce research time and cost. Against this background, quantum computational chemistry is illustrated to be a reliable tool at the onset of studies in this field, simulating charge transfer, spectral (solar energy absorbed) and electrochemical (ease by which electrons may be liberated) tuning of related photo-responsive dyes. Comparative experimental and theoretical DFT studies were done under similar conditions, involving an extended series of electrochemically altered phenanthrolines, bipyridyl and terpyridyl complexes of Fe II . Fe II/III oxidation waves vary from 0.363 V for tris(3,6-dimethoxybipyridyl)Fe II to 0.894 V (versus Fc/Fc + ) for the 5-nitrophenanthroline complex. Theoretical DFT computed ionization potentials in the bipyridyl sub-series achieved an almost 100% linear correlation with experimental electrochemical oxidation potentials, while the phenanthroline sub-series gave R 2 = 0.95. Apart from the terpyridyl complex which accorded an almost perfect match, in general, TDDFT oscillators were computed at slightly lower energies than what was observed experimentally, while molecular HOMO and LUMO renderings reveal desired complexes with directional charge transfer propensities.

  8. Licit and illicit drugs: a group approach with teenagers

    Deborah Amaral Donnini

    2017-06-01

    Full Text Available This work is an extension intervention arising from the results of an epidemiological cross-sectional study with 605 teenagers from 13 to 16 years old. The extension actions had as a method the group educational practice on licit and illicit drugs, with 2.012 teenagers from 22 municipal and state public schools of the urban region of Divinópolis, State of Minas Gerais, Brazil, from March 2015 to February 2016. It aimed to work with group educational practices on licit and illicit drugs in the school environment with teenagers. The extension and research allowed us to understand the context in which adolescents were inserted through the communication kept with them and among them; to know the level of information the teenagers had about licit and illicit drugs; to provide new knowledges, attitudes and opportunities in the recreation of an own way of selfcare. It was stressed that education is an important tool for health promotion and prevention of risks and hazards, as well as plays a key role in the formation of the proactive subject.

  9. Performance analysis of demodulation with diversity -- A combinatorial approach I: Symmetric function theoretical methods

    Jean-Louis Dornstetter

    2002-12-01

    Full Text Available This paper is devoted to the presentation of a combinatorial approach, based on the theory of symmetric functions, for analyzing the performance of a family of demodulation methods used in mobile telecommunications.

  10. Performance analysis of demodulation with diversity -- A combinatorial approach I: Symmetric function theoretical methods

    Jean-Louis Dornstetter; Daniel Krob; Jean-Yves Thibon; Ekaterina A. Vassilieva

    2002-01-01

    This paper is devoted to the presentation of a combinatorial approach, based on the theory of symmetric functions, for analyzing the performance of a family of demodulation methods used in mobile telecommunications.

  11. A Game-theoretical Approach for Distributed Cooperative Control of Autonomous Underwater Vehicles

    Lu, Yimeng

    2018-01-01

    design and learning process of the algorithm are modified to fit specific constraints of underwater exploration/monitoring tasks. The revised approach can take the real scenario of underwater monitoring applications such as the effect of sea current

  12. The combined theoretical and experimental approach to arrive at optimum parameters in friction stir welding

    Jagadeesha, C. B.

    2017-12-01

    Even though friction stir welding was invented long back (1991) by TWI England, till now there has no method or procedure or approach developed, which helps to obtain quickly optimum or exact parameters yielding good or sound weld. An approach has developed in which an equation has been derived, by which approximate rpm can be obtained and by setting range of rpm ±100 or 50 rpm over approximate rpm and by setting welding speed equal to 60 mm/min or 50 mm/min one can conduct FSW experiment to reach optimum parameters; one can reach quickly to optimum parameters, i.e. desired rpm, and welding speed, which yield sound weld by the approach. This approach can be effectively used to obtain sound welds for all similar and dissimilar combinations of materials such as Steel, Al, Mg, Ti, etc.

  13. A Comparison of Approaches for Solving Hard Graph-Theoretic Problems

    2015-04-29

    and Search”, in Discrete Mathematics and Its Applications, Book 7, CRC Press (1998): Boca Raton. [6] A. Lucas, “Ising Formulations of Many NP Problems...owner. 14. ABSTRACT In order to formulate mathematical conjectures likely to be true, a number of base cases must be determined. However, many... combinatorial problems are NP-hard and the computational complexity makes this research approach difficult using a standard brute force approach on a

  14. An Enhanced Genetic Approach to Composing Cooperative Learning Groups for Multiple Grouping Criteria

    Hwang, Gwo-Jen; Yin, Peng-Yeng; Hwang, Chi-Wei; Tsai, Chin-Chung

    2008-01-01

    Cooperative learning is known to be an effective educational strategy in enhancing the learning performance of students. The goal of a cooperative learning group is to maximize all members' learning efficacy. This is accomplished via promoting each other's success, through assisting, sharing, mentoring, explaining, and encouragement. To achieve…

  15. Task Type and Group Motivation: Implications for a Behavioral Approach to Leadership in Small Groups.

    Latham, Van M.

    1987-01-01

    Discusses a theory of leadership effectiveness in small discussion/decision making groups developed to facilitate discussion and goal efficacy. Develops four leadership styles (coordinator, inventor, enthusiast, and director) focusing on two critical questions the leader must address. Discusses implications of the model for leadership training and…

  16. Higgs inflation and quantum gravity: an exact renormalisation group approach

    Saltas, Ippocratis D.

    2016-01-01

    We use the Wilsonian functional Renormalisation Group (RG) to study quantum corrections for the Higgs inflationary action including the effect of gravitons, and analyse the leading-order quantum gravitational corrections to the Higgs' quartic coupling, as well as its non-minimal coupling to gravity and Newton's constant, at the inflationary regime and beyond. We explain how within this framework the effect of Higgs and graviton loops can be sufficiently suppressed during inflation, and we also place a bound on the corresponding value of the infrared RG cut-off scale during inflation. Finally, we briefly discuss the potential embedding of the model within the scenario of Asymptotic Safety, while all main equations are explicitly presented

  17. Human-Computer Interaction and Sociological Insight: A Theoretical Examination and Experiment in Building Affinity in Small Groups

    Oren, Michael Anthony

    2011-01-01

    The juxtaposition of classic sociological theory and the, relatively, young discipline of human-computer interaction (HCI) serves as a powerful mechanism for both exploring the theoretical impacts of technology on human interactions as well as the application of technological systems to moderate interactions. It is the intent of this dissertation…

  18. Three-dimensionality of space and the quantum bit: an information-theoretic approach

    Müller, Markus P; Masanes, Lluís

    2013-01-01

    It is sometimes pointed out as a curiosity that the state space of quantum two-level systems, i.e. the qubit, and actual physical space are both three-dimensional and Euclidean. In this paper, we suggest an information-theoretic analysis of this relationship, by proving a particular mathematical result: suppose that physics takes place in d spatial dimensions, and that some events happen probabilistically (not assuming quantum theory in any way). Furthermore, suppose there are systems that carry ‘minimal amounts of direction information’, interacting via some continuous reversible time evolution. We prove that this uniquely determines spatial dimension d = 3 and quantum theory on two qubits (including entanglement and unitary time evolution), and that it allows observers to infer local spatial geometry from probability measurements. (paper)

  19. THE NECESSITY OF APPROACHING THE ENTERPRISE PERFORMANCE CONCEPT THROUGH A THEORETICAL FUNDAMENTAL SYSTEM

    DEAC VERONICA

    2017-10-01

    Full Text Available The purpose of this paper is to justify the necessity of building of a theoretical-fundamental system to define and delimitate the integrated notions applicable to the concept of enterprise performance. Standing as a fundamental research, the present paper argues and shows that the literature in this field and the applied environment, as well, require a more clearer segregation, respectively an increase of specificity of the concept "enterprise performance" considering that it is not unanimously defined, on one hand, and, especially, due to the fact that it represents a key concept widely used, which, ultimately, has to be measured in order to be helpful, on the other hand. Moreover, the present paper would be useful to scholars working in the field of firm performance who are willing to understand this concept and to develop the future research referring to enterprise performance measurement.

  20. Role of word-of-mouth for programs of voluntary vaccination: A game-theoretic approach.

    Bhattacharyya, Samit; Bauch, Chris T; Breban, Romulus

    2015-11-01

    We propose a model describing the synergetic feedback between word-of-mouth (WoM) and epidemic dynamics controlled by voluntary vaccination. The key feature consists in combining a game-theoretic model for the spread of WoM and a compartmental model describing VSIR disease dynamics in the presence of a program of voluntary vaccination. We evaluate and compare two scenarios for determinants of behavior, depending on what WoM disseminates: (1) vaccine advertising, which may occur whether or not an epidemic is ongoing and (2) epidemic status, notably disease prevalence. Understanding the synergy between the two strategies could be particularly important for designing voluntary vaccination campaigns. We find that, in the initial phase of an epidemic, vaccination uptake is determined more by vaccine advertising than the epidemic status. As the epidemic progresses, epidemic status becomes increasingly important for vaccination uptake, considerably accelerating vaccination uptake toward a stable vaccination coverage. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. On Innovation: A Theoretical Approach on the Challenges of Utilities Marketing

    Florina PÎNZARU

    2012-06-01

    Full Text Available One of the markets not long ago closed and completely regulated is now in the growing process of liberalization and deregulation: it is the utilities market we refer to (water, sewege, gas, electricity, waste collection. The deregulation of a market is usually followed by the appearance of competition expression conditions and, unassailably, the occurrence of specific marketing strategies. This paper investigates the specific of utilities marketing as it develops now, an bourgeoning domain, although with a rather discreet presence in this field’s theoretical analysis studies. Exploratory research on the analysis type products, promotional offers and communication of this market’s players shows an effervescent players practice, but also a continuous innovation necessary in a market where consumers are unfamiliar with bein persuaded by commercial means

  2. A theoretical approach to the restoration of azulejos by re-firing

    João Manuel Mimoso

    2016-01-01

    Full Text Available LNEC found, as a by-product of another research project, that in at least some cases, glazed ceramic tiles (azulejos could be restored by re-firing. The re-firing of façade glazed tiles as a viable alternative to their outright dumping should, in principle, present no doubts. However the mere idea of restoring in the kiln brings forth methodologic arguments unparalleled in other restoration techniques. The present communication discusses the re-firing of azulejos based on theoretical restoration principles, aiming to demonstrate that it cannot be discarded straightforwardly without considering individually its advantages and possible applications. However, and although no damaging consequences where identified, the eventual application of this method to azulejos that are not considered as industrial products still requires complementary studies regarding its long-term dangerousness.

  3. Field theory approaches to new media practices: An introduction and some theoretical considerations

    Ida Willig

    2015-05-01

    Full Text Available In this article introducing the theme of the special issue we argue that studies of new media practices might benefit from especially Pierre Bourdieu’s research on cultural production. We introduce some of the literature, which deals with the use of digital media, and which have taken steps to develop field theory in this context. Secondly, we present the four thematic articles in this issue and the articles outside the theme, which includes two translations of classic texts within communication and media research. This introduction article concludes by encouraging media scholars to embark on more studies within a field theory framework, as the ability of the comprehensive theoretical work and the ideas of a reflexive sociology is able to trigger the good questions, more than it claims to offer a complete and self-sufficient sociology of media and inherent here also new media.

  4. Formation of Virtual Organizations in Grids: A Game-Theoretic Approach

    Carroll, Thomas E.; Grosu, Daniel

    The execution of large scale grid applications requires the use of several computational resources owned by various Grid Service Providers (GSPs). GSPs must form Virtual Organizations (VOs) to be able to provide the composite resource to these applications. We consider grids as self-organizing systems composed of autonomous, self-interested GSPs that will organize themselves into VOs with every GSP having the objective of maximizing its profit. We formulate the resource composition among GSPs as a coalition formation problem and propose a game-theoretic framework based on cooperation structures to model it. Using this framework, we design a resource management system that supports the VO formation among GSPs in a grid computing system.

  5. Structural modeling and analysis of an effluent treatment process for electroplating--a graph theoretic approach.

    Kumar, Abhishek; Clement, Shibu; Agrawal, V P

    2010-07-15

    An attempt is made to address a few ecological and environment issues by developing different structural models for effluent treatment system for electroplating. The effluent treatment system is defined with the help of different subsystems contributing to waste minimization. Hierarchical tree and block diagram showing all possible interactions among subsystems are proposed. These non-mathematical diagrams are converted into mathematical models for design improvement, analysis, comparison, storage retrieval and commercially off-the-shelf purchases of different subsystems. This is achieved by developing graph theoretic model, matrix models and variable permanent function model. Analysis is carried out by permanent function, hierarchical tree and block diagram methods. Storage and retrieval is done using matrix models. The methodology is illustrated with the help of an example. Benefits to the electroplaters/end user are identified. 2010 Elsevier B.V. All rights reserved.

  6. A New Theoretical Approach to Single-Molecule Fluorescence Optical Studies of RNA Dynamics

    Zhao Xinghai; Shan Guangcun; Bao Shuying

    2011-01-01

    Single-molecule fluorescence spectroscopy in condensed phases has many important chemical and biological applications. The single-molecule fluorescence measurements contain information about conformational dynamics on a vast range of time scales. Based on the data analysis protocols methodology proposed by X. Sunney Xie, the theoretical study here mainly focuses on the single-molecule studies of single RNA with interconversions among different conformational states, to with a single FRET pair attached. We obtain analytical expressions for fluorescence lifetime correlation functions that relate changes in fluorescence lifetime to the distance-dependent FRET mechanism within the context of the Smoluchowski diffusion model. The present work establishes useful guideline for the single-molecule studies of biomolecules to reveal the complicated folding dynamics of single RNA molecules at nanometer scale.

  7. Matched pairs approach to set theoretic solutions of the Yang-Baxter equation

    Gateva-Ivanova, T.; Majid, S.

    2005-08-01

    We study set-theoretic solutions (X,r) of the Yang-Baxter equations on a set X in terms of the induced left and right actions of X on itself. We give a characterization of involutive square-free solutions in terms of cyclicity conditions. We characterise general solutions in terms of an induced matched pair of unital semigroups S(X,r) and construct (S,r S ) from the matched pair. Finally, we study extensions of solutions in terms of matched pairs of their associated semigroups. We also prove several general results about matched pairs of unital semigroups of the required type, including iterated products S bowtie S bowtie S underlying the proof that r S is a solution, and extensions (S bowtie T, r Sb owtie T ). Examples include a general 'double' construction (S bowtie S,r Sb owtie S ) and some concrete extensions, their actions and graphs based on small sets. (author)

  8. Theoretical Approach to Synergistic Interaction of Ionizing Radiation with Other Factors

    Kim, Jin Kyu; Petinb, Vladislav G.

    2005-01-01

    Living objects including men are never exposed to merely one harmful agent. Many physical, chemical, biological and social factors may simultaneously exert their deleterious influence to man and the environment. Risk assessment is generally performed with the simplest assumption that the factor under consideration acts largely independently of others. However, the combined exposure to two harmful agents could result in a higher effect than would be expected from the addition of the separate exposures to individual agents. Hence, there is a possibility that, at least at high exposures, the combined effect of ionizing radiation with other environmental factors can be resulted in a greater overall risk. The problem is not so clear for low intensity and there is no possibility of testing all conceivable combinations of agents. For further insight into the mode of synergistic interaction, discussed are a common feature of synergistic interaction display and a theoretical model to describe, optimize and predict the synergistic effects

  9. A game theoretical approach for QoS provisioning in heterogeneous networks

    A.S.M. Zadid Shifat

    2015-09-01

    Full Text Available With the proliferation of mobile phone users, interference management is a big concern in this neoteric years. To cope with this problem along with ensuring better Quality of Service (QoS, femtocell plays an imperious preamble in heterogeneous networks (HetNets for some of its noteworthy characteristics. In this paper, we propose a game theoretic algorithm along with dynamic channel allocation and hybrid access mechanism with self-organizing power control scheme. With a view to resolving prioritized access issue, the concept of primary and secondary users is applied. Existence of pure strategy Nash equilibrium (NE has been investigated and comes to a perfection that our proposed scheme can be adopted both increasing capacity and increasing revenue of operators considering optimal price for consumers.

  10. Transmedial Worlds: Conceptual Review and Theoretical Approaches on the Art of Worldmaking

    Nieves Rosendo Sánchez

    2016-01-01

    Full Text Available The concept of transmedia storytelling introduced by Henry Jenkins (2003, 2006 has been widely developed in the academic field, getting popular and being redefined with time. In transmedia storytelling’s definition we can observe the focus on the concept of world, which from a theoretical and critical perspective did not had the development that the relationship among narrative and media had. This work gathers and analyzes a selection of references from the main authors that have defined the nature, limits and transferability of the so called transmedial worlds, proposing conclusions related to the need to observe the phenomenon of transmedia narratives, its founding elements and the processes related to them, with the aim to elaborate a catalogue of criteria for the analysis and consideration of key element of transmedia storytelling.

  11. Insights into Glycol Ether-Alkanol Mixtures from a Combined Experimental and Theoretical Approach.

    Alcalde, Rafael; Gutiérrez, Alberto; Atilhan, Mert; Trenzado, José Luis; Aparicio, Santiago

    2017-06-08

    The binary liquid mixtures of glycol ethers (glymes) + 1-alkanol were characterized from the microscopic and macroscopic viewpoints through a combined experimental and theoretical study. Structuring, dynamics, and intermolecular forces were determined using density functional theory and classical molecular dynamics methods. The macroscopic behavior was studied though the measurement of relevant physicochemical properties and Raman IR studies. The changes in intermolecular forces with mixture composition, temperature, and the effects from the types of glymes as well as 1-alkanols were considered. Hydrogen bonding in the mixed fluids, its changes upon mixing, and mixture composition showed a large effect on fluids' structure and determined most of the fluids' properties together with the presence of hydrophobic domains from long 1-alkanols.

  12. Theoretical and methodological approaches to determining the effectiveness of medical services

    Yu. Yu. Shvets

    2016-01-01

    Full Text Available The article analyzes the results of theoretical and methodological studies on the effectiveness of the health care system. It formulated the concept and components of the efficiency of medical services it is an economic category of health care operations. In particular, it is determined that the efficiency of medical services is a characteristic effect and shows the feasibility of the use of material, financial and human resources in this event, method, intervention. The results showed that in respect of medical services is determined by the medical, social and economic efficiency, between which there is a relationship and interdependence. The article analyzes the fundamentals and methodological bases of social, medical and economic efficiency of medical services. It was determined that a priority in the health system are the very social and medical effectiveness, taking into account those of socially important tasks to perform which is directed the whole health system in the country. Given the ambiguous understanding of the relationship of efficiency of medical services with its quality, based on the analysis of theoretical developments, identified the common and distinctive features of the characteristics of the health service in order to determine their impact on software quality and affordable health care services to the population. In particular, the efficiency of medical services is considered in close conjunction with its quality. The quality and efficiency of medical services are interrelated characteristics. However, the results showed that it is not always effective healthcare services, particularly in terms of economic efficiency, can be qualitative, and not always high-quality medical services – can be called economically efficient.

  13. Exploring the Impact of Students' Learning Approach on Collaborative Group Modeling of Blood Circulation

    Lee, Shinyoung; Kang, Eunhee; Kim, Heui-Baik

    2015-01-01

    This study aimed to explore the effect on group dynamics of statements associated with deep learning approaches (DLA) and their contribution to cognitive collaboration and model development during group modeling of blood circulation. A group was selected for an in-depth analysis of collaborative group modeling. This group constructed a model in a…

  14. Renormalization group approach to a p-wave superconducting model

    Continentino, Mucio A.; Deus, Fernanda; Caldas, Heron

    2014-01-01

    We present in this work an exact renormalization group (RG) treatment of a one-dimensional p-wave superconductor. The model proposed by Kitaev consists of a chain of spinless fermions with a p-wave gap. It is a paradigmatic model of great actual interest since it presents a weak pairing superconducting phase that has Majorana fermions at the ends of the chain. Those are predicted to be useful for quantum computation. The RG allows to obtain the phase diagram of the model and to study the quantum phase transition from the weak to the strong pairing phase. It yields the attractors of these phases and the critical exponents of the weak to strong pairing transition. We show that the weak pairing phase of the model is governed by a chaotic attractor being non-trivial from both its topological and RG properties. In the strong pairing phase the RG flow is towards a conventional strong coupling fixed point. Finally, we propose an alternative way for obtaining p-wave superconductivity in a one-dimensional system without spin–orbit interaction.

  15. Dynamical renormalization group approach to relaxation in quantum field theory

    Boyanovsky, D.; Vega, H.J. de

    2003-01-01

    The real time evolution and relaxation of expectation values of quantum fields and of quantum states are computed as initial value problems by implementing the dynamical renormalization group (DRG). Linear response is invoked to set up the renormalized initial value problem to study the dynamics of the expectation value of quantum fields. The perturbative solution of the equations of motion for the field expectation values of quantum fields as well as the evolution of quantum states features secular terms, namely terms that grow in time and invalidate the perturbative expansion for late times. The DRG provides a consistent framework to resum these secular terms and yields a uniform asymptotic expansion at long times. Several relevant cases are studied in detail, including those of threshold infrared divergences which appear in gauge theories at finite temperature and lead to anomalous relaxation. In these cases the DRG is shown to provide a resummation akin to Bloch-Nordsieck but directly in real time and that goes beyond the scope of Bloch-Nordsieck and Dyson resummations. The nature of the resummation program is discussed in several examples. The DRG provides a framework that is consistent, systematic, and easy to implement to study the non-equilibrium relaxational dynamics directly in real time that does not rely on the concept of quasiparticle widths

  16. Theoretical approaches to many-body perturbation theory and the challenges

    Barrett, Bruce R

    2005-01-01

    A brief review of the history of many-body perturbation theory (MBPT) and its applications in nuclear physics is given. Problems regarding its application to nuclear-structure calculations are discussed and analysed. It is concluded that the usefulness of nuclear MBPT in terms of an expansion in the nuclear reaction matrix G for the calculation of effective interactions in shell-model investigations is severely challenged and restricted by the problems and uncertainties connected with this approach. New methods based on unitary transformation approaches have proven to be more accurate and reliable, particularly for light nuclei

  17. Psychological resilience: an approach to the concept, theoretical framework and relation with child sexual abuse

    Cristian Gustavo Pinto-Cortez

    2014-11-01

    Full Text Available Child sexual abuse is a serious public health problem and a violation of human rights from children and adolescents. A prolific research has been developed to determine the magnitude of the problem, psychological effects, risk factors and protective factors. In this context, resilience approach becomes important by explain the mechanisms that promote positive adaptation to adversity. In this paper, it is discussed in the first part, the analysis of the concept of resilience and its various stages of investigation over time. Finally, an integration of this model in understanding and approaching child and adolescent victimization is done.

  18. 2-D Fused Image Reconstruction approach for Microwave Tomography: a theoretical assessment using FDTD Model.

    Bindu, G; Semenov, S

    2013-01-01

    This paper describes an efficient two-dimensional fused image reconstruction approach for Microwave Tomography (MWT). Finite Difference Time Domain (FDTD) models were created for a viable MWT experimental system having the transceivers modelled using thin wire approximation with resistive voltage sources. Born Iterative and Distorted Born Iterative methods have been employed for image reconstruction with the extremity imaging being done using a differential imaging technique. The forward solver in the imaging algorithm employs the FDTD method of solving the time domain Maxwell's equations with the regularisation parameter computed using a stochastic approach. The algorithm is tested with 10% noise inclusion and successful image reconstruction has been shown implying its robustness.

  19. A Theoretical Framework for Media Law Courses (Approaches to Teaching Freedom of Expression).

    Helle, Steven

    1991-01-01

    Suggests that most students prefer teachers have a theme that provides coherence and cohesiveness to media law courses. Explains how libertarian and neoliberal themes can guide learning and enumerates some of the principles of the two theories. Identifies drawbacks of the case analysis approach to such courses. (SG)

  20. Free radical scavenging and COX-2 inhibition by simple colon metabolites of polyphenols: A theoretical approach.

    Amić, Ana; Marković, Zoran; Marković, Jasmina M Dimitrić; Jeremić, Svetlana; Lučić, Bono; Amić, Dragan

    2016-12-01

    Free radical scavenging and inhibitory potency against cyclooxygenase-2 (COX-2) by two abundant colon metabolites of polyphenols, i.e., 3-hydroxyphenylacetic acid (3-HPAA) and 4-hydroxyphenylpropionic acid (4-HPPA) were theoretically studied. Different free radical scavenging mechanisms are investigated in water and pentyl ethanoate as a solvent. By considering electronic properties of scavenged free radicals, hydrogen atom transfer (HAT) and sequential proton loss electron transfer (SPLET) mechanisms are found to be thermodynamically probable and competitive processes in both media. The Gibbs free energy change for reaction of inactivation of free radicals indicates 3-HPAA and 4-HPPA as potent scavengers. Their reactivity toward free radicals was predicted to decrease as follows: hydroxyl>alkoxyls>phenoxyl≈peroxyls>superoxide. Shown free radical scavenging potency of 3-HPAA and 4-HPPA along with their high μM concentration produced by microbial colon degradation of polyphenols could enable at least in situ inactivation of free radicals. Docking analysis with structural forms of 3-HPAA and 4-HPPA indicates dianionic ligands as potent inhibitors of COX-2, an inducible enzyme involved in colon carcinogenesis. Obtained results suggest that suppressing levels of free radicals and COX-2 could be achieved by 3-HPAA and 4-HPPA indicating that these compounds may contribute to reduced risk of colon cancer development. Copyright © 2016 Elsevier Ltd. All rights reserved.