Renormalization group-theoretic approach to electron localization in disordered systems

International Nuclear Information System (INIS)

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

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

NARCIS (Netherlands)

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

Theoretical Approaches to Political Communication.

Science.gov (United States)

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…

UNCERTAINTY IN NEOCLASSICAL AND KEYNESIAN THEORETICAL APPROACHES: A BEHAVIOURAL PERSPECTIVE

Directory of Open Access Journals (Sweden)

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.

A Set Theoretical Approach to Maturity Models

DEFF Research Database (Denmark)

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...

Nursing leadership in a chronic pain management group approach.

Science.gov (United States)

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.

Theoretical Approaches to Coping

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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.

One-dimensional barcode reading: an information theoretic approach

Science.gov (United States)

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.

The dynamics of alliances. A game theoretical approach

NARCIS (Netherlands)

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

Theoretical approaches to social innovation – A critical literature review

NARCIS (Netherlands)

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

Radiotherapy problem under fuzzy theoretic approach

International Nuclear Information System (INIS)

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

31st International Colloquium in Group Theoretical Methods in Physics

CERN Document Server

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 ...

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

International Nuclear Information System (INIS)

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.)

Group-Theoretical Revision of the Unruh Effect

International Nuclear Information System (INIS)

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.

Group-Theoretical Revision of the Unruh Effect

Energy Technology Data Exchange (ETDEWEB)

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.

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

NARCIS (Netherlands)

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

Theoretical Issues in Clinical Social Group Work.

Science.gov (United States)

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…

A gauge-theoretic approach to gravity.

Science.gov (United States)

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.

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

Directory of Open Access Journals (Sweden)

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.

Computational and Game-Theoretic Approaches for Modeling Bounded Rationality

NARCIS (Netherlands)

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

SOCIOLOGICAL UNDERSTANDING OF INTERNET: THEORETICAL APPROACHES TO THE NETWORK ANALYSIS

Directory of Open Access Journals (Sweden)

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. 

Preservation of Newspapers: Theoretical Approaches and Practical Achievements

Science.gov (United States)

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,…

Dramaturgical and Music-Theoretical Approaches to Improvisation Pedagogy

Science.gov (United States)

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,…

Choice Shifts in Groups: A Decision-Theoretic Basis

OpenAIRE

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...

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

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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

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

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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

New Theoretical Approach Integrated Education and Technology

Science.gov (United States)

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…

BEHAVIORAL INPUTS TO THE THEORETICAL APPROACH OF THE ECONOMIC CRISIS

Directory of Open Access Journals (Sweden)

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.

Partial discharge transients: The field theoretical approach

DEFF Research Database (Denmark)

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....

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

Science.gov (United States)

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.

A Game Theoretic Approach to Nuclear Security Analysis against Insider Threat

Energy Technology Data Exchange (ETDEWEB)

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

A Game Theoretic Approach to Nuclear Security Analysis against Insider Threat

International Nuclear Information System (INIS)

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

Twistor-theoretic approach to topological field theories

International Nuclear Information System (INIS)

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)

Child education and management: theoretical approaches on legislation

Directory of Open Access Journals (Sweden)

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.

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

OpenAIRE

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...

A queer-theoretical approach to community health psychology.

Science.gov (United States)

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.

Non-commutative cryptography and complexity of group-theoretic problems

CERN Document Server

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...

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

Science.gov (United States)

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.

A relevance theoretic approach to intertextuality in print advertising

African Journals Online (AJOL)

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.

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

Science.gov (United States)

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.

Group-theoretical aspects of the discrete sine-Gordon equation

International Nuclear Information System (INIS)

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

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

Energy Technology Data Exchange (ETDEWEB)

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.

Theoretical and methodological approaches in discourse analysis.

Science.gov (United States)

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.

Theoretical and methodological approaches in discourse analysis.

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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

Multiple stakeholders in road pricing: A game theoretic approach

NARCIS (Netherlands)

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

Theoretical Approaches to Nuclear Proliferation

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

A sign-theoretic approach to biotechnology

DEFF Research Database (Denmark)

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...

A System Theoretical Inspired Approach to Knowledge Construction

DEFF Research Database (Denmark)

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...

The Theoretical and Empirical Approaches to the Definition of Audit Risk

Directory of Open Access Journals (Sweden)

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.

Model selection and inference a practical information-theoretic approach

CERN Document Server

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 ...

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

Energy Technology Data Exchange (ETDEWEB)

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)

A theoretical approach to artificial intelligence systems in medicine.

Science.gov (United States)

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.

Group theoretical symmetries and generalized Bäcklund transformations for integrable systems

Science.gov (United States)

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.

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

NARCIS (Netherlands)

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

Monoenergetic approximation of a polyenergetic beam: a theoretical approach

International Nuclear Information System (INIS)

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)

Blogging in Higher Education: Theoretical and Practical Approach

OpenAIRE

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...

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

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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

Theoretical and expert system approach to photoionization theories

Directory of Open Access Journals (Sweden)

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.

Group theoretical analysis of octahedral tilting in perovskites

International Nuclear Information System (INIS)

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

A game-theoretic approach to real-time system testing

DEFF Research Database (Denmark)

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....

Special functions group theoretical aspects and applications

CERN Document Server

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 ...

Introduction to superfluidity field-theoretical approach and applications

CERN Document Server

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.

Nuclear Fermi Dynamics: physical content versus theoretical approach

International Nuclear Information System (INIS)

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.''

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

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

Group theoretical methods and wavelet theory: coorbit theory and applications

Science.gov (United States)

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

SOCIOLOGICAL UNDERSTANDING OF INTERNET: THEORETICAL APPROACHES TO THE NETWORK ANALYSIS

Directory of Open Access Journals (Sweden)

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. 

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

International Nuclear Information System (INIS)

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)

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

Science.gov (United States)

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.

Group theoretical quantization of isotropic loop cosmology

Science.gov (United States)

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.

An Activity Theoretical Approach to Social Interaction during Study Abroad

Science.gov (United States)

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,…

Relativistic kinematics and dynamics: a new group theoretical approach

International Nuclear Information System (INIS)

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.)

Towards a Set Theoretical Approach to Big Data Analytics

DEFF Research Database (Denmark)

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...

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

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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

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

Energy Technology Data Exchange (ETDEWEB)

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.

Analytic game—theoretic approach to ground-water extraction

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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

Different Approaches to Cross-Lingual Focus Groups

Directory of Open Access Journals (Sweden)

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.

Theoretical approaches to determining the financial provision of public transportation

Directory of Open Access Journals (Sweden)

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.

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

CERN Document Server

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.

Vanadium supersaturated silicon system: a theoretical and experimental approach

Science.gov (United States)

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.

How cells engulf: a review of theoretical approaches to phagocytosis

Science.gov (United States)

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.

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

International Nuclear Information System (INIS)

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.

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

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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. �

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

Energy Technology Data Exchange (ETDEWEB)

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

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

International Nuclear Information System (INIS)

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.)

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

Research in theoretical nuclear physics

International Nuclear Information System (INIS)

Udagawa, T.

1993-11-01

This report describes the accomplishments in basic research in nuclear physics carried out by the theoretical nuclear physics group in the Department of Physics at the University of Texas at Austin, during the period of November 1, 1992 to October 31, 1993. The work done covers three separate areas, low-energy nuclear reactions, intermediate energy physics, and nuclear structure studies. Although the subjects are thus spread among different areas, they are based on two techniques developed in previous years. These techniques are a powerful method for continuum-random-phase-approximation (CRPA) calculations of nuclear response and the breakup-fusion (BF) approach to incomplete fusion reactions, which calculation on a single footing of various incomplete fusion reaction cross sections within the framework of direct reaction theories. The approach was developed as a part of a more general program for establishing an approach to describing all different types of nuclear reactions, i.e., complete fusion, incomplete fusion and direct reactions, in a systematic way based on single theoretical framework

Theoretical orientations in environmental planning: An inquiry into alternative approaches

Science.gov (United States)

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.

Group theoretic reduction of Laplacian dynamical problems on fractal lattices

International Nuclear Information System (INIS)

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

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

Science.gov (United States)

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

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

Science.gov (United States)

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.

Information Ergonomics A theoretical approach and practical experience in transportation

CERN Document Server

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...

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

International Nuclear Information System (INIS)

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

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

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

Success Determination by Innovation: A Theoretical Approach in Marketing

Directory of Open Access Journals (Sweden)

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.

Success Determination by Innovation: A Theoretical Approach in Marketing

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

Directory of Open Access Journals (Sweden)

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 approaches – theoretical and functional.

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

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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.

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

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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.

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

DEFF Research Database (Denmark)

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...

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

International Nuclear Information System (INIS)

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.

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

International Nuclear Information System (INIS)

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.)

Factors determining early internationalization of entrepreneurial SMEs: Theoretical approach

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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.

Theoretical Approaches to Lignin Chemistry

OpenAIRE

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.

Recent Theoretical Approaches to Minimal Artificial Cells

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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.

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

International Nuclear Information System (INIS)

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

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

KAUST Repository

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.

The Group Treatment of Bulimia.

Science.gov (United States)

Weinstein, Harvey M.; Richman, Ann

1984-01-01

Bulimia has become an increasing problem in the college population. This article describes a group psychotherapeutic treatment approach to the problem. A theoretical formulation of the psychodynamics that may underlie the development of bulimia is offered. (Author/DF)

HIGH: A Hexagon-based Intelligent Grouping Approach in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

FAN, C.-S.

2016-02-01

Full Text Available In a random deployment or uniform deployment strategy, sensor nodes are scattered randomly or uniformly in the sensing field, respectively. Hence, the coverage ratio cannot be guaranteed. The coverage ratio of uniform deployment, in general, is larger than that of the random deployment strategy. However, a random deployment or uniform deployment strategy may cause unbalanced traffic pattern in wireless sensor networks (WSNs. Therefore, cluster heads (CHs around the sink have larger loads than those farther away from the sink. That is, CHs close to the sink exhaust their energy earlier. In order to overcome the above problem, we propose a Hexagon-based Intelligent Grouping approacH in WSNs (called HIGH. The coverage, energy consumption and data routing issues are well investigated and taken into consideration in the proposed HIGH scheme. The simulation results validate our theoretical analysis and show that the proposed HIGH scheme achieves a satisfactory coverage ratio, balances the energy consumption among sensor nodes, and extends network lifetime significantly.

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

International Nuclear Information System (INIS)

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

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

Science.gov (United States)

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.

Information-Theoretic Approaches for Evaluating Complex Adaptive Social Simulation Systems

Energy Technology Data Exchange (ETDEWEB)

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.

Investigations on Actuator Dynamics through Theoretical and Finite Element Approach

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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)

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

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

International Nuclear Information System (INIS)

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.

Group theoretical methods in Physics

International Nuclear Information System (INIS)

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

ORGANIZATIONAL WORK GROUPS AND WORK TEAMS – APPROACHES AND DIFFERENCES

Directory of Open Access Journals (Sweden)

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.

How do small groups make decisions?

OpenAIRE

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

2017-01-01

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 e...

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

Science.gov (United States)

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.

An integrated theoretical and practical approach for teaching hydrogeology

Science.gov (United States)

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

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

CERN Document Server

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...

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

Directory of Open Access Journals (Sweden)

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

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

Science.gov (United States)

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

Child Language Acquisition: Contrasting Theoretical Approaches

Science.gov (United States)

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…

Optimization of rootkit revealing system resources – A game theoretic approach

Directory of Open Access Journals (Sweden)

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.

A theoretical approach to photosynthetically active radiation silicon sensor

International Nuclear Information System (INIS)

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

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

Directory of Open Access Journals (Sweden)

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.

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.

Science.gov (United States)

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.

Machine learning a theoretical approach

CERN Document Server

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

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

International Nuclear Information System (INIS)

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

Group Theoretical Approach for Controlled Quantum Mechanical Systems

National Research Council Canada - National Science Library

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...

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

Science.gov (United States)

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…

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

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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.

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

International Nuclear Information System (INIS)

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

Molecular approach of uranyl/mineral surfaces: theoretical approach

International Nuclear Information System (INIS)

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

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

OpenAIRE

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.

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

Science.gov (United States)

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.

Emotional collectives: How groups shape emotions and emotions shape groups.

Science.gov (United States)

van Kleef, Gerben A; Fischer, Agneta H

2016-01-01

Group settings are epicentres of emotional activity. Yet, the role of emotions in groups is poorly understood. How do group-level phenomena shape group members' emotional experience and expression? How are emotional expressions recognised, interpreted and shared in group settings? And how do such expressions influence the emotions, cognitions and behaviours of fellow group members and outside observers? To answer these and other questions, we draw on relevant theoretical perspectives (e.g., intergroup emotions theory, social appraisal theory and emotions as social information theory) and recent empirical findings regarding the role of emotions in groups. We organise our review according to two overarching themes: how groups shape emotions and how emotions shape groups. We show how novel empirical approaches break important new ground in uncovering the role of emotions in groups. Research on emotional collectives is thriving and constitutes a key to understanding the social nature of emotions.

An effectiveness analysis of healthcare systems using a systems theoretic approach

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

Renormalization group in modern physics

International Nuclear Information System (INIS)

Shirkov, D.V.

1988-01-01

Renormalization groups used in diverse fields of theoretical physics are considered. The discussion is based upon functional formulation of group transformations. This attitude enables development of a general method by using the notion of functional self-similarity which generalizes the usual self-similarity connected with power similarity laws. From this point of view the authors present a simple derivation of the renorm-group (RG) in QFT liberated from ultra-violet divergences philosophy, discuss the RG approach in other fields of physics and compare different RG's

Theoretical nuclear physics

CERN Document Server

Blatt, John M

1979-01-01

A classic work by two leading physicists and scientific educators endures as an uncommonly clear and cogent investigation and correlation of key aspects of theoretical nuclear physics. It is probably the most widely adopted book on the subject. The authors approach the subject as ""the theoretical concepts, methods, and considerations which have been devised in order to interpret the experimental material and to advance our ability to predict and control nuclear phenomena.""The present volume does not pretend to cover all aspects of theoretical nuclear physics. Its coverage is restricted to

Group manifold approach to gravity and supergravity theories

International Nuclear Information System (INIS)

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

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

Science.gov (United States)

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.

Algebraic and group treatments to nonlinear displaced number states and their nonclassicality features: A new approach

International Nuclear Information System (INIS)

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)

Determination of 54 pesticides in waters of the Iberian Douro River estuary and risk assessment of environmentally relevant mixtures using theoretical approaches and Artemia salina and Daphnia magna bioassays.

Science.gov (United States)

Cruzeiro, Catarina; Amaral, Sofia; Rocha, Eduardo; Rocha, Maria João

2017-11-01

As a case study, the estuary of the international Douro River (Iberian Peninsula) was sampled over a year (2010) at six sampling sites to determine the presence of 56 pesticides of different categories (insecticides, herbicides, and fungicides). 96% of measured pesticides were detected in 79% of the quantified samples. Individual average pesticide concentrations ranged from 39 to 1 265ng/L, indicating a ubiquitous presence of the selected compounds; moreover, twelve pesticides were above the 2013/39/EU Directive limits. Due to its highly impacted profile, a theoretical hazard assessment was done considering the average and maximum environmental mixtures of all measured pesticides to identify the most sensitive trophic level. For both environmental mixtures, the theoretical approach suggested that invertebrates were the most sensitive group. Therefore, short-time exposure assays using both invertebrates Artemia salina and Daphnia magna, were done using the referred mixtures. Data demonstrated significant toxic effects ─ high mortality rate and abnormal swimming behaviour ─ of the exposed animals. Both approaches (theoretical and experimental) support the analytical results, alerting for an intervention on this estuarine environment and of other comparable. Copyright © 2017 Elsevier Inc. All rights reserved.

Optimization of Investment Planning Based on Game-Theoretic Approach

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

International Nuclear Information System (INIS)

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.

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

Science.gov (United States)

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…

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

Science.gov (United States)

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)

New approach to the adjustment of group cross sections fitting integral measurements

International Nuclear Information System (INIS)

Chao, Y.A.

1979-01-01

The adjustment of group cross sections fitting integral measurements is viewed as a process of estimating theoretical and/or experimental negligence errors to bring statistical consistency to the integral and differential data so that they can be combined to form an enlarged ensemble, based on which an improved estimation of the physical constants can be made. A three-step approach is suggested, and its formalism of general validity is developed. In step one, the data of negligence error are extracted from the given integral and differential data. The method of extraction is based on the concepts of prior probability and information entropy. It automatically leads to vanishing negligence error as the two sets of data are statistically consistent. The second step is to identify the sources of negligence error and adjust the data by an amount compensating for the extracted negligence discrepancy. In the last step, the two data sets, already adjusted to mutual consistency are combined as a single unified ensemble. Standard methods of statistics can then be applied to reestimate the physical constants. 1 figure

A Theoretical Explanation of Marital Conflicts by Paradigmatic Approach

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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.

An approach to grouping species for ecological risk assessment

International Nuclear Information System (INIS)

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

Feminist Principles in Survivor's Groups: Out-of-Group Contact.

Science.gov (United States)

Rittenhouse, JoAn

1997-01-01

Illustrates the value of theoretical concepts from Feminist Therapy in the group treatment of women survivors. Theoretical underpinnings are supported using data taken from clinical experience and by examining group themes and out-of-group contact developed from the case sample. Principles regarding feminist groups are proposed. (RJM)

A game theoretic approach to assignment problems

NARCIS (Netherlands)

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

The group-as-a-whole-object relations model of group psychotherapy.

Science.gov (United States)

Rosen, D; Stukenberg, K W; Saeks, S

2001-01-01

The authors review the theoretical basis of group psychotherapy performed at The Menninger Clinic and demonstrate how the theory has been put into practice on two different types of inpatient units. The fundamental elements of the theory and practice used can be traced to object relations theory as originally proposed by Melanie Klein. Her work with individuals was directly applied to working with groups by Ezriel and Bion, who focused on interpreting group tension. More modern approaches have reintegrated working with individual concerns while also attending to the group-as-a-whole. Historically, these principles have been applied to long-term group treatment. The authors apply the concepts from the group-as-a-whole literature to short- and medium-length inpatient groups with open membership. They offer clinical examples of the application of these principles in short-term inpatient settings in groups with open membership.

A cultural psychological approach to evangelical faith healing groups

NARCIS (Netherlands)

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

Theoretical chemistry in Belgium a topical collection from theoretical chemistry accounts

CERN Document Server

Champagne, Benoît; De Proft, Frank; Leyssens, Tom

2014-01-01

Readers of this volume can take a tour around the research locations in Belgium which are active in theoretical and computational chemistry. Selected researchers from Belgium present research highlights of their work. Originally published in the journal Theoretical Chemistry Accounts, these outstanding contributions are now available in a hardcover print format. This volume will be of benefit in particular to those research groups and libraries that have chosen to have only electronic access to the journal. It also provides valuable content for all researchers in theoretical chemistry.

Functional renormalization group approach to the two dimensional Bose gas

Energy Technology Data Exchange (ETDEWEB)

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.

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

Directory of Open Access Journals (Sweden)

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.

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

DEFF Research Database (Denmark)

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....

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

Directory of Open Access Journals (Sweden)

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.

Set-theoretic methods in control

CERN Document Server

Blanchini, Franco

2015-01-01

The second edition of this monograph describes the set-theoretic approach for the control and analysis of dynamic systems, both from a theoretical and practical standpoint.  This approach is linked to fundamental control problems, such as Lyapunov stability analysis and stabilization, optimal control, control under constraints, persistent disturbance rejection, and uncertain systems analysis and synthesis.  Completely self-contained, this book provides a solid foundation of mathematical techniques and applications, extensive references to the relevant literature, and numerous avenues for further theoretical study. All the material from the first edition has been updated to reflect the most recent developments in the field, and a new chapter on switching systems has been added.  Each chapter contains examples, case studies, and exercises to allow for a better understanding of theoretical concepts by practical application. The mathematical language is kept to the minimum level necessary for the adequate for...

A Semiparametric Bayesian Approach for Analyzing Longitudinal Data from Multiple Related Groups.

Science.gov (United States)

Das, Kiranmoy; Afriyie, Prince; Spirko, Lauren

2015-11-01

Often the biological and/or clinical experiments result in longitudinal data from multiple related groups. The analysis of such data is quite challenging due to the fact that groups might have shared information on the mean and/or covariance functions. In this article, we consider a Bayesian semiparametric approach of modeling the mean trajectories for longitudinal response coming from multiple related groups. We consider matrix stick-breaking process priors on the group mean parameters which allows information sharing on the mean trajectories across the groups. Simulation studies are performed to demonstrate the effectiveness of the proposed approach compared to the more traditional approaches. We analyze data from a one-year follow-up of nutrition education for hypercholesterolemic children with three different treatments where the children are from different age-groups. Our analysis provides more clinically useful information than the previous analysis of the same dataset. The proposed approach will be a very powerful tool for analyzing data from clinical trials and other medical experiments.

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

Science.gov (United States)

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.

Theoretical Physics Division

International Nuclear Information System (INIS)

This report is a survey of the studies done in the Theoretical Physics Division of the Nuclear Physics Institute; the subjects studied in theoretical nuclear physics were the few-nucleon problem, nuclear structure, nuclear reactions, weak interactions, intermediate energy and high energy physics. In this last field, the subjects studied were field theory, group theory, symmetry and strong interactions [fr

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

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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.

A Methodological Demonstration of Set-theoretical Approach to Social Media Maturity Models Using Necessary Condition Analysis

DEFF Research Database (Denmark)

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...

An Informal Overview of the Unitary Group Approach

International Nuclear Information System (INIS)

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.

Intelligent cognitive radio jamming - a game-theoretical approach

Science.gov (United States)

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.

THEORETICAL AND METHODOLOGICAL APPROACHES TO THE STUDY OF THE IMPACT OF INFORMATION TECHNOLOGY ON SOCIAL CONNECTIONS AMONG YOUTH

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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.

Developing TheoreticalMethodological Approaches to Assessment of Export Potential of Ukrainian Enterprises

Directory of Open Access Journals (Sweden)

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.

Group theoretical classification of chemical elements

International Nuclear Information System (INIS)

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

A Century of Gestalt Psychology in Visual Perception: II. Conceptual and Theoretical Foundations

Science.gov (United States)

Wagemans, Johan; Feldman, Jacob; Gepshtein, Sergei; Kimchi, Ruth; Pomerantz, James R.; van der Helm, Peter A.; van Leeuwen, Cees

2012-01-01

Our first review article (Wagemans et al., 2012) on the occasion of the centennial anniversary of Gestalt psychology focused on perceptual grouping and figure-ground organization. It concluded that further progress requires a reconsideration of the conceptual and theoretical foundations of the Gestalt approach, which is provided here. In…

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

OpenAIRE

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,...

Group differences in the aesthetic evaluation of nature development plans : A multilevel approach

NARCIS (Netherlands)

van den Berg, A.E.; Vlek, CAJ; Coeterier, JF

The study presented here addresses theoretical, methodological and practical aspects of the issue of group differences in the aesthetic evaluation of natural landscapes. Beauty ratings of an agrarian landscape and five computer simulations of nature development plans in this landscape were collected

Wetting transitions: A functional renormalization-group approach

International Nuclear Information System (INIS)

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

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

KAUST Repository

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

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

KAUST Repository

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

A Theoretical Approach to Understanding Population Dynamics with Seasonal Developmental Durations

Science.gov (United States)

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.

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

Science.gov (United States)

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.

New approach to the adjustment of group cross-sections fitting integral measurements

International Nuclear Information System (INIS)

Chao, Y.A.

1979-01-01

The adjustment of group cross-sections fitting integral measurements is viewed as a process of uncovering theoretical and/or experimental negligence errors to bring statistical consistency to the integral and differential data so that they can be combined to form an enlarged ensemble, on which an improved estimation of the physical constants can be based. An approach with three steps is suggested, and its formalism of general validity is developed. In step one, the data of negligence error are extracted from the given integral and differential data. The method of extraction is based on the concepts of prior probability and information entropy. It automatically leads to vanishing negligence error as the two sets of data are statistically consistent. The second step is to identify the sources of negligence error and adjust the data by an amount compensating the extracted negligence discrepancy. In the last step the two data sets, already adjusted to mutual consistency, are combined as a single unified ensemble. Standard methods of statistics can then be applied to re-estimate the physical constants. A simple example is shown as a demonstration of the method. 1 figure

Parents' experiences of being in the Solihull Approach parenting group, 'Understanding Your Child's Behaviour': an interpretative phenomenological analysis.

Science.gov (United States)

Vella, L R; Butterworth, R E; Johnson, R; Law, G Urquhart

2015-11-01

Empirical evidence suggests that the Solihull Approach parenting group, 'Understanding Your Child's Behaviour' (UYCB), can improve child behaviour and parental well-being. However, little is known about parents' in-depth experience of participating in the UYCB programme. This study provides an in-depth qualitative evaluation of UYCB, focussing on possible moderating factors and mechanisms of change that may inform programme development. Ten parents (eight mothers and two fathers), recruited from seven UYCB groups across two locations, were interviewed within 7 weeks of completing the group and again 10 months later. Data were analysed using interpretative phenomenological analysis. Four themes were identified: 'Two Tiers of Satisfaction', 'Development as a Parent', 'Improved Self-belief' and 'The "Matthew Effect"'. In summary, the majority of parents were immensely satisfied at both completion and follow-up: they valued an experience of containment and social support and perceived improvement in specific child difficulties, their experience of parenting, their confidence and their coping. Most parents appeared to have developed more reflective and empathic parenting styles, with self-reported improved behaviour management. Theoretical material was well received, although some struggled with technical language. Positive outcomes appeared to be maintained, even reinforced, at follow-up, and were associated with having few initial child difficulties, perceiving improvement at completion and persevering with the recommendations. Two participants, whose children had the most severe difficulties, perceived deterioration and felt that the group was insufficient for their level of difficulties. Through in-depth analysis of parental experiences, UYCB appears to achieve its aims and communicate well its theoretical principles, although change may also occur through processes common to other group programmes (e.g. social support). Recommendations, stemming from the

Age groups related glioblastoma study based on radiomics approach.

Science.gov (United States)

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.

Game-theoretic interference coordination approaches for dynamic spectrum access

CERN Document Server

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.

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

Science.gov (United States)

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.

Group investigation with scientific approach in mathematics learning

Science.gov (United States)

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.

Linear mixed-effects modeling approach to FMRI group analysis.

Science.gov (United States)

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

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

Directory of Open Access Journals (Sweden)

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.

Theoretical Computer Science

DEFF Research Database (Denmark)

2002-01-01

The proceedings contains 8 papers from the Conference on Theoretical Computer Science. Topics discussed include: query by committee, linear separation and random walks; hardness results for neural network approximation problems; a geometric approach to leveraging weak learners; mind change...

The power of theoretical knowledge.

Science.gov (United States)

Alligood, Martha Raile

2011-10-01

Nursing theoretical knowledge has demonstrated powerful contributions to education, research, administration and professional practice for guiding nursing thought and action. That knowledge has shifted the primary focus of the nurse from nursing functions to the person. Theoretical views of the person raise new questions, create new approaches and instruments for nursing research, and expand nursing scholarship throughout the world.

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

International Nuclear Information System (INIS)

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.

Game Theoretical Approach to Supply Chain Microfinance

OpenAIRE

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...

Developing theoretically based and culturally appropriate interventions to promote hepatitis B testing in 4 Asian American populations, 2006-2011.

Science.gov (United States)

Maxwell, Annette E; Bastani, Roshan; Glenn, Beth A; Taylor, Victoria M; Nguyen, Tung T; Stewart, Susan L; Burke, Nancy J; Chen, Moon S

2014-05-01

Hepatitis B infection is 5 to 12 times more common among Asian Americans than in the general US population and is the leading cause of liver disease and liver cancer among Asians. The purpose of this article is to describe the step-by-step approach that we followed in community-based participatory research projects in 4 Asian American groups, conducted from 2006 through 2011 in California and Washington state to develop theoretically based and culturally appropriate interventions to promote hepatitis B testing. We provide examples to illustrate how intervention messages addressing identical theoretical constructs of the Health Behavior Framework were modified to be culturally appropriate for each community. Intervention approaches included mass media in the Vietnamese community, small-group educational sessions at churches in the Korean community, and home visits by lay health workers in the Hmong and Cambodian communities. Use of the Health Behavior Framework allowed a systematic approach to intervention development across populations, resulting in 4 different culturally appropriate interventions that addressed the same set of theoretical constructs. The development of theory-based health promotion interventions for different populations will advance our understanding of which constructs are critical to modify specific health behaviors.

Data Collection for Mobile Group Consumption: An Asynchronous Distributed Approach

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

[Memorandum IV: Theoretical and Normative Grounding of Health Services Research].

Science.gov (United States)

Baumann, W; Farin, E; Menzel-Begemann, A; Meyer, T

2016-05-01

With Memoranda and other initiatives, the German Network for Health Service Research [Deutsches Netzwerk Versorgungsforschung e.V. (DNVF)] is fostering the methodological quality of care research studies for years. Compared to the standards of empirical research, questions concerning the role and function of theories, theoretical approaches and scientific principles have not been taken up on its own. Therefore, the DNVF e.V. has set up a working group in 2013, which was commissioned to prepare a memorandum on "theories in health care research". This now presented memorandum will primarily challenge scholars in health care services research to pay more attention to questions concerning the theoretical arsenal and the background assumptions in the research process. The foundation in the philosophy of science, the reference to normative principles and the theory-bases of the research process are addressed. Moreover, the memorandum will call on to advance the theorizing in health services research and to strengthen not empirical approaches, research on basic principles or studies with regard to normative sciences and to incorporate these relevant disciplines in health services research. Research structures and funding of health services research needs more open space for theoretical reflection and for self-observation of their own, multidisciplinary research processes. © Georg Thieme Verlag KG Stuttgart · New York.

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

Science.gov (United States)

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…

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

Science.gov (United States)

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.

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

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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.

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

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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

Mechanisms of Enzyme-Catalyzed Reduction of Two Carcinogenic Nitro-Aromatics, 3-Nitrobenzanthrone and Aristolochic Acid I: Experimental and Theoretical Approaches

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Marie Stiborová

2014-06-01

Full Text Available This review summarizes the results found in studies investigating the enzymatic activation of two genotoxic nitro-aromatics, an environmental pollutant and carcinogen 3-nitrobenzanthrone (3-NBA and a natural plant nephrotoxin and carcinogen aristolochic acid I (AAI, to reactive species forming covalent DNA adducts. Experimental and theoretical approaches determined the reasons why human NAD(PH:quinone oxidoreductase (NQO1 and cytochromes P450 (CYP 1A1 and 1A2 have the potential to reductively activate both nitro-aromatics. The results also contributed to the elucidation of the molecular mechanisms of these reactions. The contribution of conjugation enzymes such as N,O-acetyltransferases (NATs and sulfotransferases (SULTs to the activation of 3-NBA and AAI was also examined. The results indicated differences in the abilities of 3-NBA and AAI metabolites to be further activated by these conjugation enzymes. The formation of DNA adducts generated by both carcinogens during their reductive activation by the NOQ1 and CYP1A1/2 enzymes was investigated with pure enzymes, enzymes present in subcellular cytosolic and microsomal fractions, selective inhibitors, and animal models (including knock-out and humanized animals. For the theoretical approaches, flexible in silico docking methods as well as ab initio calculations were employed. The results summarized in this review demonstrate that a combination of experimental and theoretical approaches is a useful tool to study the enzyme-mediated reaction mechanisms of 3-NBA and AAI reduction.

Mechanisms of Enzyme-Catalyzed Reduction of Two Carcinogenic Nitro-Aromatics, 3-Nitrobenzanthrone and Aristolochic Acid I: Experimental and Theoretical Approaches

Science.gov (United States)

Stiborová, Marie; Frei, Eva; Schmeiser, Heinz H.; Arlt, Volker M.; Martínek, Václav

2014-01-01

This review summarizes the results found in studies investigating the enzymatic activation of two genotoxic nitro-aromatics, an environmental pollutant and carcinogen 3-nitrobenzanthrone (3-NBA) and a natural plant nephrotoxin and carcinogen aristolochic acid I (AAI), to reactive species forming covalent DNA adducts. Experimental and theoretical approaches determined the reasons why human NAD(P)H:quinone oxidoreductase (NQO1) and cytochromes P450 (CYP) 1A1 and 1A2 have the potential to reductively activate both nitro-aromatics. The results also contributed to the elucidation of the molecular mechanisms of these reactions. The contribution of conjugation enzymes such as N,O-acetyltransferases (NATs) and sulfotransferases (SULTs) to the activation of 3-NBA and AAI was also examined. The results indicated differences in the abilities of 3-NBA and AAI metabolites to be further activated by these conjugation enzymes. The formation of DNA adducts generated by both carcinogens during their reductive activation by the NOQ1 and CYP1A1/2 enzymes was investigated with pure enzymes, enzymes present in subcellular cytosolic and microsomal fractions, selective inhibitors, and animal models (including knock-out and humanized animals). For the theoretical approaches, flexible in silico docking methods as well as ab initio calculations were employed. The results summarized in this review demonstrate that a combination of experimental and theoretical approaches is a useful tool to study the enzyme-mediated reaction mechanisms of 3-NBA and AAI reduction. PMID:24918288

Resilience or Flexibility– A Theoretical Approach on Romanian Development Regions

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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.

Group processes in medical education: learning from social identity theory.

Science.gov (United States)

Burford, Bryan

2012-02-01

The clinical workplace in which doctors learn involves many social groups, including representatives of different professions, clinical specialties and workplace teams. This paper suggests that medical education research does not currently take full account of the effects of group membership, and describes a theoretical approach from social psychology, the social identity approach, which allows those effects to be explored. The social identity approach has a long history in social psychology and provides an integrated account of group processes, from the adoption of group identity through a process of self-categorisation, to the biases and conflicts between groups. This paper outlines key elements of this theoretical approach and illustrates their relevance to medical education. The relevance of the social identity approach is illustrated with reference to a number of areas of medical education. The paper shows how research questions in medical education may be usefully reframed in terms of social identity in ways that allow a deeper exploration of the psychological processes involved. Professional identity and professionalism may be viewed in terms of self-categorisation rather than simply attainment; the salience of different identities may be considered as influences on teamwork and interprofessional learning, and issues in communication and assessment may be considered in terms of intergroup biases. Social identity theory provides a powerful framework with which to consider many areas of medical education. It allows disparate influences on, and consequences of, group membership to be considered as part of an integrated system, and allows assumptions, such as about the nature of professional identity and interprofessional tensions, to be made explicit in the design of research studies. This power to question assumptions and develop deeper and more meaningful research questions may be increasingly relevant as the nature and role of the medical profession change

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

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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.

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

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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

Theoretical progress at CNDC theory group

International Nuclear Information System (INIS)

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

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

Science.gov (United States)

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.

Hybrid rocket engine, theoretical model and experiment

Science.gov (United States)

Chelaru, Teodor-Viorel; Mingireanu, Florin

2011-06-01

The purpose of this paper is to build a theoretical model for the hybrid rocket engine/motor and to validate it using experimental results. The work approaches the main problems of the hybrid motor: the scalability, the stability/controllability of the operating parameters and the increasing of the solid fuel regression rate. At first, we focus on theoretical models for hybrid rocket motor and compare the results with already available experimental data from various research groups. A primary computation model is presented together with results from a numerical algorithm based on a computational model. We present theoretical predictions for several commercial hybrid rocket motors, having different scales and compare them with experimental measurements of those hybrid rocket motors. Next the paper focuses on tribrid rocket motor concept, which by supplementary liquid fuel injection can improve the thrust controllability. A complementary computation model is also presented to estimate regression rate increase of solid fuel doped with oxidizer. Finally, the stability of the hybrid rocket motor is investigated using Liapunov theory. Stability coefficients obtained are dependent on burning parameters while the stability and command matrixes are identified. The paper presents thoroughly the input data of the model, which ensures the reproducibility of the numerical results by independent researchers.

The Economic Security of Bank: Theoretical Basis and Systemic Approach

Directory of Open Access Journals (Sweden)

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.

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

Science.gov (United States)

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.

Family Group Conferencing: A Theoretical Underpinning

NARCIS (Netherlands)

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

Comparative regulatory approaches for groups of new plant breeding techniques.

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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 )

Innovation value chain capability in Malaysian-owned company: A theoretical framework

Science.gov (United States)

Abidin, Norkisme Zainal; Suradi, Nur Riza Mohd

2014-09-01

Good quality products or services are no longer adequate to guarantee the sustainability of a company in the present competitive business. Prior research has developed various innovation models with the hope to better understand the innovativeness of the company. Due to countless definitions, indicators, factors, parameter and approaches in the study of innovation, it is difficult to ensure which one will best suit the Malaysian-owned company innovativeness. This paper aims to provide a theoretical background to support the framework of the innovation value chain capability in Malaysian-owned Company. The theoretical framework was based on the literature reviews, expert interviews and focus group study. The framework will be used to predict and assess the innovation value chain capability in Malaysian-owned company.

A Markov game theoretic data fusion approach for cyber situational awareness

Science.gov (United States)

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.

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

Science.gov (United States)

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.

Induced representations of the affine group and intertwining operators: I. Analytical approach

International Nuclear Information System (INIS)

Elmabrok, Abdelhamid S; Hutník, Ondrej

2012-01-01

We analyze the construction and origin of unitary operators describing the structure of the space of continuous wavelet transforms inside the space L 2 (G,dν L ) of all square-integrable functions on the affine group G with respect to the left-invariant Haar measure from the viewpoint of induced representations of G. We show that these operators are, in fact, intertwining operators among pairs of induced representations of the affine group G. A characterization of the space of wavelet transforms using the Cauchy–Riemann-type equations is given. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’. (paper)

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

Directory of Open Access Journals (Sweden)

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.

Theoretical study of molecular vibrations in electron momentum spectroscopy experiments on furan: An analytical versus a molecular dynamical approach

International Nuclear Information System (INIS)

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

Group Approach to the Quantization of Non-Abelian Stueckelberg Models

International Nuclear Information System (INIS)

Aldaya, V; Lopez-Ruiz, F F; Calixto, M

2011-01-01

The quantum field theory of Non-Linear Sigma Models on coadjoint orbits of a semi-simple group G are formulated in the framework of a Group Approach to Quantization. In this scheme, partial-trace Lagrangians are recovered from two-cocycles defined on the infinite-dimensional group of sections of the jet-gauge group J 1 (G). This construction is extended to the entire physical system coupled to Yang-Mills fields, thus constituting an algebraic formulation of the Non-Abelian Stueckelgerg formalism devoid of the unitarity/renormalizability obstruction that this theory finds in the standard Lagrangian formalism under canonical quantization.

Group Approach to the Quantization of Non-Abelian Stueckelberg Models

Energy Technology Data Exchange (ETDEWEB)

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

2011-03-01

The quantum field theory of Non-Linear Sigma Models on coadjoint orbits of a semi-simple group G are formulated in the framework of a Group Approach to Quantization. In this scheme, partial-trace Lagrangians are recovered from two-cocycles defined on the infinite-dimensional group of sections of the jet-gauge group J{sup 1} (G). This construction is extended to the entire physical system coupled to Yang-Mills fields, thus constituting an algebraic formulation of the Non-Abelian Stueckelgerg formalism devoid of the unitarity/renormalizability obstruction that this theory finds in the standard Lagrangian formalism under canonical quantization.

Group Evidential Reasoning Approach for MADA under Fuzziness and Uncertainties

Directory of Open Access Journals (Sweden)

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.

A Century of Gestalt Psychology in Visual Perception II. Conceptual and Theoretical Foundations

OpenAIRE

Wagemans, Johan; Feldman, Jacob; Gepshtein, Sergei; Kimchi, Ruth; Pomerantz, James R.; van der Helm, Peter A.; van Leeuwen, Cees

2012-01-01

Our first review paper on the occasion of the centennial anniversary of Gestalt psychology focused on perceptual grouping and figure-ground organization. It concluded that further progress requires a reconsideration of the conceptual and theoretical foundations of the Gestalt approach, which is provided here. In particular, we review contemporary formulations of holism within an information-processing framework, allowing for operational definitions (e.g., integral dimensions, emergent feature...

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

Science.gov (United States)

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.

THEORETICAL AND METHODOLOGICAL APPROACHES TO REGIONAL COMPETITION INVESTIGATION

Directory of Open Access Journals (Sweden)

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.

The Emergence of Individual and Collective Leadership in Task Groups

DEFF Research Database (Denmark)

Paunova, Minna

2015-01-01

leader emergence in task groups as influenced by individual traits, states, and behaviors. However, current approaches to leadership in groups rely on functional achievement explanations of how collective leadership emerges, influenced by positive states and behaviors. Attention to ascription......This review synthesizes conceptual and empirical research on the emergence of individual and collective leadership in task groups, and proposes avenues for leadership research. To advance multilevel study of leadership emergence, including emergence of distributed and shared leadership, the paper...... reviews research on individual leader emergence, structured around two identified theoretical mechanisms—one of leadership achievement (i.e., based on functional behaviors) and another of leadership ascription (i.e., based on nominal characteristics). These approaches compete to elucidate individual...

Data Collection for Mobile Group Consumption: An Asynchronous Distributed Approach †

Science.gov (United States)

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

2016-01-01

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. PMID:27058544

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

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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)

Funding intensive care - approaches in systems using diagnosis-related groups.

OpenAIRE

Ettelt, S; Nolte, E

2010-01-01

This report reviews approaches to funding intensive care in health systems that use activitybased payment mechanisms based on diagnosis-related groups (DRGs) to reimburse hospital care. The report aims to inform the current debate about options for funding intensive care services for adults, children and newborns in England. Funding mechanisms reviewed here include those in Australia (Victoria), Denmark, France, Germany, Italy, Spain, Sweden and the United States (Medicare). Approaches to org...

Group attributional training as an effective approach to human resource development under team work systems.

Science.gov (United States)

Wang, Z M

1994-07-01

An experimental programme of group attributional training under team work system was conducted as part of human resource development in Chinese industrial enterprises. One hundred and ten shopfloor employees participated in the study. Among them, 58 employees took part in the factorial-designed experiment to find out the effects of attributions on performance, and 52 employees of ten work groups participated in the group attributional training programme twice a week for two months. The results showed that the group attributional training was effective in modifying employees' attributional patterns and enhancing group performance and satisfaction. On the basis of the results, an attributional model of work motivation is proposed, and its theoretical and practical implications for human resource management discussed.

Fuzzy Group Decision Making Approach for Ranking Work Stations Based on Physical Pressure

Directory of Open Access Journals (Sweden)

Hamed Salmanzadeh

2014-06-01

Full Text Available This paper proposes a Fuzzy Group Decision Making approach for ranking work stations based on physical pressure. Fuzzy group decision making approach allows experts to evaluate different ergonomic factors using linguistic terms such as very high, high, medium, low, very low, rather than precise numerical values. In this way, there is no need to measure parameters and evaluation can be easily made in a group. According to ergonomics much work contents and situations, accompanied with multiple parameters and uncertainties, fuzzy group decision making is the best way to evaluate such a chameleon of concept. A case study was down to utilize the approach and illustrate its application in ergonomic assessment and ranking the work stations based on work pressure and found that this approach provides flexibility, practicality, efficiency in making decision around ergonomics areas. The normalized defuzzification numbers which are resulted from this method are compared with result of quantitative assessment of Automotive Assembly Work Sheet auto, it’s demonstrated that the proposed method result is 10% less than Automotive Assembly Work Sheet, approximately.

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

Science.gov (United States)

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.

Tobacco Cessation for Adolescents: Developing a Group Therapy Approach.

Science.gov (United States)

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…

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

International Nuclear Information System (INIS)

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.

Non commutative geometry methods for group C*-algebras

International Nuclear Information System (INIS)

Do Ngoc Diep.

1996-09-01

This book is intended to provide a quick introduction to the subject. The exposition is scheduled in the sequence, as possible for more understanding for beginners. The author exposed a K-theoretic approach to study group C * -algebras: started in the elementary part, with one example of description of the structure of C * -algebra of the group of affine transformations of the real straight line, continued then for some special classes of solvable and nilpotent Lie groups. In the second advanced part, he introduced the main tools of the theory. In particular, the conception of multidimensional geometric quantization and the index of group C * -algebras were created and developed. (author). Refs

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

Science.gov (United States)

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).

Concept maps and nursing theory: a pedagogical approach.

Science.gov (United States)

Hunter Revell, Susan M

2012-01-01

Faculty seek to teach nursing students how to link clinical and theoretical knowledge with the intent of improving patient outcomes. The author discusses an innovative 9-week concept mapping activity as a pedagogical approach to teach nursing theory in a graduate theory course. Weekly concept map building increased student engagement and fostered theoretical thinking. Unexpectedly, this activity also benefited students through group work and its ability to enhance theory-practice knowledge.

Space-group approach to two-electron states in unconventional superconductors

International Nuclear Information System (INIS)

Yarzhemsky, V. G.

2008-01-01

The direct application of the space-group representation theory, makes possible to obtain limitations for the symmetry of SOP on lines and planes of symmetry in one-electron Brillouin zone. In the case of highly symmetric UPt 3 only theoretical nodal structure of IR E 2u is in agreement with all the experimental results. On the other hand, in the case of high-T c superconductors the two electron description of Cooper pairs in D 2h symmetry is not sufficient to describe experimental nodal structure. It was shown that in this case, the nodal structure is the result of underlying interactions between two-electron states and hidden symmetry D-4 h . (author)

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

International Nuclear Information System (INIS)

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

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

International Nuclear Information System (INIS)

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.)

The group-theoretical approach to the description of nuclear states

International Nuclear Information System (INIS)

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

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

International Nuclear Information System (INIS)

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

Aperture Array Photonic Metamaterials: Theoretical approaches, numerical techniques and a novel application

Science.gov (United States)

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.

External Validity in the Study of Human Development: Theoretical and Methodological Issues

Science.gov (United States)

Hultsch, David F.; Hickey, Tom

1978-01-01

An examination of the concept of external validity from two theoretical perspectives: a traditional mechanistic approach and a dialectical organismic approach. Examines the theoretical and methodological implications of these perspectives. (BD)

ANALYSIS OF THEORETICAL AND METHODOLOGICAL APPROACHES TO DESIGN OF ELECTRONIC TEXTBOOKS FOR STUDENTS OF HIGHER AGRICULTURAL EDUCATIONAL INSTITUTIONS

Directory of Open Access Journals (Sweden)

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.

A combined experimental and theoretical approach to establish the relationship between shear force and clay platelet delamination in melt-processed polypropylene nanocomposites

CSIR Research Space (South Africa)

Bandyopadhyay, J

2014-04-01

Full Text Available In this article, a combined experimental and theoretical approach has been proposed to establish a relationship between the required shear force and the degree of delamination of clay tactoids during the melt-processing of polymer nanocomposites...

Theoretical and methodological approaches to economic competitiveness (Part I

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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.

Theoretical and methodological approaches to economic competitiveness (part II

Directory of Open Access Journals (Sweden)

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.

THEORETICAL AND METHODOLOGICAL APPROACHES TO ECONOMIC COMPETITIVENESS (Part II

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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.

THEORETICAL AND METHODOLOGICAL APPROACHES TO ECONOMIC COMPETITIVENESS (Part I

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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.)

Representing electrons a biographical approach to theoretical entities

CERN Document Server

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

Theoretical clarity is not “Manicheanism”

DEFF Research Database (Denmark)

Hjørland, Birger

2011-01-01

It is argued that in order to establish a new theoretical approach to information science it is necessary to express disagreement with some established views. The “social turn” in information science is not just exemplified in relation to the works of Marcia Bates but in relation to many different...... researchers in the field. Therefore it should not be taken personally, and the debate should focus on the substance. Marcia Bates has contributed considerably to information science. In spite of this some of her theoretical points of departure may be challenged. It is important to seek theoretical clarity...... and this may involve a degree of schematic confrontation that should not be confused with theoretical one-sidedness, “Manicheanism” or lack of respect....

The production of scientific videos: a theoretical approach

Directory of Open Access Journals (Sweden)

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. 

A Theoretical and Methodological Evaluation of Leadership Research.

Science.gov (United States)

Lashbrook, Velma J.; Lashbrook, William B.

This paper isolates some of the strengths and weaknesses of leadership research by evaluating it from both a theoretical and methodological perspective. The seven theories or approaches examined are: great man, trait, situational, style, functional, social influence, and interaction positions. General theoretical, conceptual, and measurement…

Achieving behaviour change for detection of Lynch syndrome using the Theoretical Domains Framework Implementation (TDFI) approach: a study protocol.

Science.gov (United States)

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

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

Science.gov (United States)

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.

Singing as Language Learning Activity in Multilingual Toddler Groups in Preschool

Science.gov (United States)

Kultti, Anne

2013-01-01

This research focused on learning conditions in preschool that support multilingual children's linguistic development. The aim of this paper was to study singing activities through the experiences of ten multilingual children in toddler groups (one to three years of age) in eight Swedish preschools. A sociocultural theoretical approach is used to…

A Comparison of Jungian, Person-Centered, and Gestalt Approaches to Personal Growth Groups.

Science.gov (United States)

Day, Bryon; Matthes, William

1992-01-01

Compares Jungian approach to personal growth groups to Person-centered and Gestalt approaches. Notes similarities, though Jungian approach adds dimension of "cognitive map" not found in other two. Notes that cognitive map uses constructs from Jung's theory of individuation process, hypothesizing that integration of these constructs into…

Grouping and Read-Across Approaches for Risk Assessment of Nanomaterials.

Science.gov (United States)

Oomen, Agnes G; Bleeker, Eric A J; Bos, Peter M J; van Broekhuizen, Fleur; Gottardo, Stefania; Groenewold, Monique; Hristozov, Danail; Hund-Rinke, Kerstin; Irfan, Muhammad-Adeel; Marcomini, Antonio; Peijnenburg, Willie J G M; Rasmussen, Kirsten; Jiménez, Araceli Sánchez; Scott-Fordsmand, Janeck J; van Tongeren, Martie; Wiench, Karin; Wohlleben, Wendel; Landsiedel, Robert

2015-10-26

Physicochemical properties of chemicals affect their exposure, toxicokinetics/fate and hazard, and for nanomaterials, the variation of these properties results in a wide variety of materials with potentially different risks. To limit the amount of testing for risk assessment, the information gathering process for nanomaterials needs to be efficient. At the same time, sufficient information to assess the safety of human health and the environment should be available for each nanomaterial. Grouping and read-across approaches can be utilised to meet these goals. This article presents different possible applications of grouping and read-across for nanomaterials within the broader perspective of the MARINA Risk Assessment Strategy (RAS), as developed in the EU FP7 project MARINA. Firstly, nanomaterials can be grouped based on limited variation in physicochemical properties to subsequently design an efficient testing strategy that covers the entire group. Secondly, knowledge about exposure, toxicokinetics/fate or hazard, for example via properties such as dissolution rate, aspect ratio, chemical (non-)activity, can be used to organise similar materials in generic groups to frame issues that need further attention, or potentially to read-across. Thirdly, when data related to specific endpoints is required, read-across can be considered, using data from a source material for the target nanomaterial. Read-across could be based on a scientifically sound justification that exposure, distribution to the target (fate/toxicokinetics) and hazard of the target material are similar to, or less than, the source material. These grouping and read-across approaches pave the way for better use of available information on nanomaterials and are flexible enough to allow future adaptations related to scientific developments.

Grouping and Read-Across Approaches for Risk Assessment of Nanomaterials

Directory of Open Access Journals (Sweden)

Agnes G. Oomen

2015-10-01

Full Text Available Physicochemical properties of chemicals affect their exposure, toxicokinetics/fate and hazard, and for nanomaterials, the variation of these properties results in a wide variety of materials with potentially different risks. To limit the amount of testing for risk assessment, the information gathering process for nanomaterials needs to be efficient. At the same time, sufficient information to assess the safety of human health and the environment should be available for each nanomaterial. Grouping and read-across approaches can be utilised to meet these goals. This article presents different possible applications of grouping and read-across for nanomaterials within the broader perspective of the MARINA Risk Assessment Strategy (RAS, as developed in the EU FP7 project MARINA. Firstly, nanomaterials can be grouped based on limited variation in physicochemical properties to subsequently design an efficient testing strategy that covers the entire group. Secondly, knowledge about exposure, toxicokinetics/fate or hazard, for example via properties such as dissolution rate, aspect ratio, chemical (non-activity, can be used to organise similar materials in generic groups to frame issues that need further attention, or potentially to read-across. Thirdly, when data related to specific endpoints is required, read-across can be considered, using data from a source material for the target nanomaterial. Read-across could be based on a scientifically sound justification that exposure, distribution to the target (fate/toxicokinetics and hazard of the target material are similar to, or less than, the source material. These grouping and read-across approaches pave the way for better use of available information on nanomaterials and are flexible enough to allow future adaptations related to scientific developments.

Domino effects within a chemical cluster: a game-theoretical modeling approach by using Nash-equilibrium.

Science.gov (United States)

Reniers, Genserik; Dullaert, Wout; Karel, Soudan

2009-08-15

Every company situated within a chemical cluster faces domino effect risks, whose magnitude depends on every company's own risk management strategies and on those of all others. Preventing domino effects is therefore very important to avoid catastrophes in the chemical process industry. Given that chemical companies are interlinked by domino effect accident links, there is some likelihood that even if certain companies fully invest in domino effects prevention measures, they can nonetheless experience an external domino effect caused by an accident which occurred in another chemical enterprise of the cluster. In this article a game-theoretic approach to interpret and model behaviour of chemical plants within chemical clusters while negotiating and deciding on domino effects prevention investments is employed.

The current status of theoretically based approaches to the prediction of the critical heat flux in flow boiling

International Nuclear Information System (INIS)

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

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

Directory of Open Access Journals (Sweden)

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.

Strategy for a numerical Rock Mechanics Site Descriptive Model. Further development of the theoretical/numerical approach

International Nuclear Information System (INIS)

Olofsson, Isabelle; Fredriksson, Anders

2005-05-01

The Swedish Nuclear and Fuel Management Company (SKB) is conducting Preliminary Site Investigations at two different locations in Sweden in order to study the possibility of a Deep Repository for spent fuel. In the frame of these Site Investigations, Site Descriptive Models are achieved. These products are the result of an interaction of several disciplines such as geology, hydrogeology, and meteorology. The Rock Mechanics Site Descriptive Model constitutes one of these models. Before the start of the Site Investigations a numerical method using Discrete Fracture Network (DFN) models and the 2D numerical software UDEC was developed. Numerical simulations were the tool chosen for applying the theoretical approach for characterising the mechanical rock mass properties. Some shortcomings were identified when developing the methodology. Their impacts on the modelling (in term of time and quality assurance of results) were estimated to be so important that the improvement of the methodology with another numerical tool was investigated. The theoretical approach is still based on DFN models but the numerical software used is 3DEC. The main assets of the programme compared to UDEC are an optimised algorithm for the generation of fractures in the model and for the assignment of mechanical fracture properties. Due to some numerical constraints the test conditions were set-up in order to simulate 2D plane strain tests. Numerical simulations were conducted on the same data set as used previously for the UDEC modelling in order to estimate and validate the results from the new methodology. A real 3D simulation was also conducted in order to assess the effect of the '2D' conditions in the 3DEC model. Based on the quality of the results it was decided to update the theoretical model and introduce the new methodology based on DFN models and 3DEC simulations for the establishment of the Rock Mechanics Site Descriptive Model. By separating the spatial variability into two parts, one

User and Document Group Approach of Clustering in Tagging Systems

DEFF Research Database (Denmark)

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....

Applications of the renormalization group approach to problems in quantum field theory

International Nuclear Information System (INIS)

Renken, R.L.

1985-01-01

The presence of fluctuations at many scales of length complicates theories of quantum fields. However, interest is often focused on the low-energy consequences of a theory rather than the short distance fluctuations. In the renormalization-group approach, one takes advantage of this by constructing an effective theory with identical low-energy behavior, but without short distance fluctuations. Three problems of this type are studied here. In chapter 1, an effective lagrangian is used to compute the low-energy consequences of theories of technicolor. Corrections to weak-interaction parameters are found to be small, but conceivably measurable. In chapter 2, the renormalization group approach is applied to second order phase transitions in lattice gauge theories such as the deconfining transition in the U(1) theory. A practical procedure for studying the critical behavior based on Monte Carlo renormalization group methods is described in detail; no numerical results are presented. Chapter 3 addresses the problem of computing the low-energy behavior of atoms directly from Schrodinger's equation. A straightforward approach is described, but is found to be impractical

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

Energy Technology Data Exchange (ETDEWEB)

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

Theoretical Division annual report, FY 1975

International Nuclear Information System (INIS)

Carruthers, P.A.

1976-02-01

This report presents an overview of the activities in the Theoretical Division and a summary of research highlights during FY 1975. It is intended to inform a wide audience about the theoretical work of the LASL and, therefore, contains introductory material which places recent advances in a broader context. The report is organized into two special interest reports: reactor safety research and the Advanced Research Committee, and 11 reports from the T-Division group leaders on the work of their respective groups. Main interests and responsibilities are outlined including the relationship of the group's work to the work of other T-Division groups and other divisions at the Laboratory. The description of research highlights for FY 1975 explains in a fairly simple, straightforward manner the major recent advances and their significance. Each group report is followed by a publication list for FY 1975 (330 references) and a list of talks given outside the Laboratory (140 references). 29 figures

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

Directory of Open Access Journals (Sweden)

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.

What is the optimal value of the g-ratio for myelinated fibers in the rat CNS? A theoretical approach.

Directory of Open Access Journals (Sweden)

Taylor Chomiak

2009-11-01

Full Text Available The biological process underlying axonal myelination is complex and often prone to injury and disease. The ratio of the inner axonal diameter to the total outer diameter or g-ratio is widely utilized as a functional and structural index of optimal axonal myelination. Based on the speed of fiber conduction, Rushton was the first to derive a theoretical estimate of the optimal g-ratio of 0.6 [1]. This theoretical limit nicely explains the experimental data for myelinated axons obtained for some peripheral fibers but appears significantly lower than that found for CNS fibers. This is, however, hardly surprising given that in the CNS, axonal myelination must achieve multiple goals including reducing conduction delays, promoting conduction fidelity, lowering energy costs, and saving space.In this study we explore the notion that a balanced set-point can be achieved at a functional level as the micro-structure of individual axons becomes optimized, particularly for the central system where axons tend to be smaller and their myelin sheath thinner. We used an intuitive yet novel theoretical approach based on the fundamental biophysical properties describing axonal structure and function to show that an optimal g-ratio can be defined for the central nervous system (approximately 0.77. Furthermore, by reducing the influence of volume constraints on structural design by about 40%, this approach can also predict the g-ratio observed in some peripheral fibers (approximately 0.6.These results support the notion of optimization theory in nervous system design and construction and may also help explain why the central and peripheral systems have evolved different g-ratios as a result of volume constraints.

What is the optimal value of the g-ratio for myelinated fibers in the rat CNS? A theoretical approach.

Science.gov (United States)

Chomiak, Taylor; Hu, Bin

2009-11-13

The biological process underlying axonal myelination is complex and often prone to injury and disease. The ratio of the inner axonal diameter to the total outer diameter or g-ratio is widely utilized as a functional and structural index of optimal axonal myelination. Based on the speed of fiber conduction, Rushton was the first to derive a theoretical estimate of the optimal g-ratio of 0.6 [1]. This theoretical limit nicely explains the experimental data for myelinated axons obtained for some peripheral fibers but appears significantly lower than that found for CNS fibers. This is, however, hardly surprising given that in the CNS, axonal myelination must achieve multiple goals including reducing conduction delays, promoting conduction fidelity, lowering energy costs, and saving space. In this study we explore the notion that a balanced set-point can be achieved at a functional level as the micro-structure of individual axons becomes optimized, particularly for the central system where axons tend to be smaller and their myelin sheath thinner. We used an intuitive yet novel theoretical approach based on the fundamental biophysical properties describing axonal structure and function to show that an optimal g-ratio can be defined for the central nervous system (approximately 0.77). Furthermore, by reducing the influence of volume constraints on structural design by about 40%, this approach can also predict the g-ratio observed in some peripheral fibers (approximately 0.6). These results support the notion of optimization theory in nervous system design and construction and may also help explain why the central and peripheral systems have evolved different g-ratios as a result of volume constraints.

Trophic interaction modifications: an empirical and theoretical framework.

Science.gov (United States)

Terry, J Christopher D; Morris, Rebecca J; Bonsall, Michael B

2017-10-01

Consumer-resource interactions are often influenced by other species in the community. At present these 'trophic interaction modifications' are rarely included in ecological models despite demonstrations that they can drive system dynamics. Here, we advocate and extend an approach that has the potential to unite and represent this key group of non-trophic interactions by emphasising the change to trophic interactions induced by modifying species. We highlight the opportunities this approach brings in comparison to frameworks that coerce trophic interaction modifications into pairwise relationships. To establish common frames of reference and explore the value of the approach, we set out a range of metrics for the 'strength' of an interaction modification which incorporate increasing levels of contextual information about the system. Through demonstrations in three-species model systems, we establish that these metrics capture complimentary aspects of interaction modifications. We show how the approach can be used in a range of empirical contexts; we identify as specific gaps in current understanding experiments with multiple levels of modifier species and the distributions of modifications in networks. The trophic interaction modification approach we propose can motivate and unite empirical and theoretical studies of system dynamics, providing a route to confront ecological complexity. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Distinguishing prognostic and predictive biomarkers: An information theoretic approach.

Science.gov (United States)

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.

SUSTAINABLE TOURISM AND ITS FORMS - A THEORETICAL APPROACH

Directory of Open Access Journals (Sweden)

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

Renormalization group approach to superfluid neutron matter

Energy Technology Data Exchange (ETDEWEB)

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.)

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

Directory of Open Access Journals (Sweden)

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.

Theoretical approaches to digital services and digital democracy

DEFF Research Database (Denmark)

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...

Broadening the Study of Participation in the Life Sciences: How Critical Theoretical and Mixed-Methodological Approaches Can Enhance Efforts to Broaden Participation

Science.gov (United States)

Metcalf, Heather

2016-01-01

This research methods Essay details the usefulness of critical theoretical frameworks and critical mixed-methodological approaches for life sciences education research on broadening participation in the life sciences. First, I draw on multidisciplinary research to discuss critical theory and methodologies. Then, I demonstrate the benefits of these…

Game theoretic analysis of physical protection system design

International Nuclear Information System (INIS)

Canion, B.; Schneider, E.; Bickel, E.; Hadlock, C.; Morton, D.

2013-01-01

The physical protection system (PPS) of a fictional small modular reactor (SMR) facility have been modeled as a platform for a game theoretic approach to security decision analysis. To demonstrate the game theoretic approach, a rational adversary with complete knowledge of the facility has been modeled attempting a sabotage attack. The adversary adjusts his decisions in response to investments made by the defender to enhance the security measures. This can lead to a conservative physical protection system design. Since defender upgrades were limited by a budget, cost benefit analysis may be conducted upon security upgrades. One approach to cost benefit analysis is the efficient frontier, which depicts the reduction in expected consequence per incremental increase in the security budget

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

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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)

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

Energy Technology Data Exchange (ETDEWEB)

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)

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

Science.gov (United States)

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.

Understanding small biomolecule-biomaterial interactions: a review of fundamental theoretical and experimental approaches for biomolecule interactions with inorganic surfaces.

Science.gov (United States)

Costa, Dominique; Garrain, Pierre-Alain; Baaden, Marc

2013-04-01

Interactions between biomolecules and inorganic surfaces play an important role in natural environments and in industry, including a wide variety of conditions: marine environment, ship hulls (fouling), water treatment, heat exchange, membrane separation, soils, mineral particles at the earth's surface, hospitals (hygiene), art and buildings (degradation and biocorrosion), paper industry (fouling) and more. To better control the first steps leading to adsorption of a biomolecule on an inorganic surface, it is mandatory to understand the adsorption mechanisms of biomolecules of several sizes at the atomic scale, that is, the nature of the chemical interaction between the biomolecule and the surface and the resulting biomolecule conformations once adsorbed at the surface. This remains a challenging and unsolved problem. Here, we review the state of art in experimental and theoretical approaches. We focus on metallic biomaterial surfaces such as TiO(2) and stainless steel, mentioning some remarkable results on hydroxyapatite. Experimental techniques include atomic force microscopy, surface plasmon resonance, quartz crystal microbalance, X-ray photoelectron spectroscopy, fluorescence microscopy, polarization modulation infrared reflection absorption spectroscopy, sum frequency generation and time of flight secondary ion mass spectroscopy. Theoretical models range from detailed quantum mechanical representations to classical forcefield-based approaches. Copyright © 2012 Wiley Periodicals, Inc.

A Hybrid Chaotic and Number Theoretic Approach for Securing DICOM Images

Directory of Open Access Journals (Sweden)

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.

Group theoretical construction of planar noncommutative phase spaces

Energy Technology Data Exchange (ETDEWEB)

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.

Group theoretical construction of planar noncommutative phase spaces

International Nuclear Information System (INIS)

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

Improved Membership Probability for Moving Groups: Bayesian and Machine Learning Approaches

Science.gov (United States)

Lee, Jinhee; Song, Inseok

2018-01-01

Gravitationally unbound loose stellar associations (i.e., young nearby moving groups: moving groups hereafter) have been intensively explored because they are important in planet and disk formation studies, exoplanet imaging, and age calibration. Among the many efforts devoted to the search for moving group members, a Bayesian approach (e.g.,using the code BANYAN) has become popular recently because of the many advantages it offers. However, the resultant membership probability needs to be carefully adopted because of its sensitive dependence on input models. In this study, we have developed an improved membership calculation tool focusing on the beta-Pic moving group. We made three improvements for building models used in BANYAN II: (1) updating a list of accepted members by re-assessing memberships in terms of position, motion, and age, (2) investigating member distribution functions in XYZ, and (3) exploring field star distribution functions in XYZUVW. Our improved tool can change membership probability up to 70%. Membership probability is critical and must be better defined. For example, our code identifies only one third of the candidate members in SIMBAD that are believed to be kinematically associated with beta-Pic moving group.Additionally, we performed cluster analysis of young nearby stars using an unsupervised machine learning approach. As more moving groups and their members are identified, the complexity and ambiguity in moving group configuration has been increased. To clarify this issue, we analyzed ~4,000 X-ray bright young stellar candidates. Here, we present the preliminary results. By re-identifying moving groups with the least human intervention, we expect to understand the composition of the solar neighborhood. Moreover better defined moving group membership will help us understand star formation and evolution in relatively low density environments; especially for the low-mass stars which will be identified in the coming Gaia release.

Theoretical Physics. Lectures presented at the Seminar on Theoretical Physics

Energy Technology Data Exchange (ETDEWEB)

NONE

1963-01-15

The seminar on Theoretical Physics was held in Trieste, Italy, from 16 July to 25 of August 1962 and was organized by the International Atomic Energy Agency. The published proceedings of the lectures consist of five books. Book I is concerned with quantum field theory in its axiomatic as well as lagrangian formulations. Part 1 is a survey by Wightman of the recent achievements of the axiomatic approach followed by an account from Wigner of some of the less known representations of the Lorentz Group (continuous spin and imaginary mass representations) which may possibly acquire relevance in connection with theories of Regge poles. Part two of Book I consists of Schwinger’s lectures on the structure of Gauge Theories of Vector Particles and an account of his recent ideas about gauge invariance and its connection with mass. Book II is devoted to the symmetry properties of elementary particles with an experimental review by Capps and a survey of the formalism of Lie groups by Salam. A number of contributions by Gatto, Sakurai and others specialize to particular Lie groups, exploring the possibility of testing which, if any, of the higher symmetries are in fact realized in nature. Book III is concerned with complex angular momenta and Mandelstam representation, with major lecture courses from Regge, Fubini, Mandelstam and Froissart. A shorter Book IV surveys some recent dynamical investigations of πN and NN Systems as well as compound models of elementary particles (Thirring). The concluding part of this volume (Book V) is different in spirit from the rest. Its concern is with the emerging topic of very high energies, with a survey of strong interactions from Hayakawa, of electromagnetic interactions from Ericsson and others and of weak interactions at very high energies from Pais.

Theoretical Physics. Lectures presented at the Seminar on Theoretical Physics

International Nuclear Information System (INIS)

1963-01-01

The seminar on Theoretical Physics was held in Trieste, Italy, from 16 July to 25 of August 1962 and was organized by the International Atomic Energy Agency. The published proceedings of the lectures consist of five books. Book I is concerned with quantum field theory in its axiomatic as well as lagrangian formulations. Part 1 is a survey by Wightman of the recent achievements of the axiomatic approach followed by an account from Wigner of some of the less known representations of the Lorentz Group (continuous spin and imaginary mass representations) which may possibly acquire relevance in connection with theories of Regge poles. Part two of Book I consists of Schwinger’s lectures on the structure of Gauge Theories of Vector Particles and an account of his recent ideas about gauge invariance and its connection with mass. Book II is devoted to the symmetry properties of elementary particles with an experimental review by Capps and a survey of the formalism of Lie groups by Salam. A number of contributions by Gatto, Sakurai and others specialize to particular Lie groups, exploring the possibility of testing which, if any, of the higher symmetries are in fact realized in nature. Book III is concerned with complex angular momenta and Mandelstam representation, with major lecture courses from Regge, Fubini, Mandelstam and Froissart. A shorter Book IV surveys some recent dynamical investigations of πN and NN Systems as well as compound models of elementary particles (Thirring). The concluding part of this volume (Book V) is different in spirit from the rest. Its concern is with the emerging topic of very high energies, with a survey of strong interactions from Hayakawa, of electromagnetic interactions from Ericsson and others and of weak interactions at very high energies from Pais.

Renormalization group approach in the turbulence theory

International Nuclear Information System (INIS)

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

The Role of Perceived In-group Moral Superiority in Reparative Intentions and Approach Motivation.

Science.gov (United States)

Szabó, Zsolt P; Mészáros, Noémi Z; Csertő, István

2017-01-01

Three studies examined how members of a national group react to in-group wrongdoings. We expected that perceived in-group moral superiority would lead to unwillingness to repair the aggression. We also expected that internal-focused emotions such as group-based guilt and group-based shame would predict specific, misdeed-related reparative intentions but not general approach motivation toward the victim groups. In Study 1, facing the in-group's recent aggression, participants who believed that the Hungarians have been more moral throughout their history than members of other nations, used more exonerating cognitions, experienced less in-group critical emotions and showed less willingness to provide reparations for the members of the victim group. Study 2 and Study 3 confirmed most findings of Study 1. Perceived in-group moral superiority directly or indirectly reduced willingness to provide either general or specific reparations, while internally focused in-group critical emotions predicted specific misdeed-related reparative intentions but not general approach motivation. The role of emotional attachment to the in-group is considered.

On the information-theoretic approach to G\\"odel's incompleteness theorem

OpenAIRE

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.

Renormalization group approach to Sudakov resummation in prompt photon production

International Nuclear Information System (INIS)

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

Functionalization of glassy carbon surface by means of aliphatic and aromatic amino acids. An experimental and theoretical integrated approach

International Nuclear Information System (INIS)

Vanossi, Davide; Benassi, Rois; Parenti, Francesca; Tassinari, Francesco; Giovanardi, Roberto; Florini, Nicola; De Renzi, Valentina; Arnaud, Gaelle; Fontanesi, Claudio

2012-01-01

Highlights: ► Glassy carbon is functionalized via electrochemical assisted grafting of amino acids. ► The grafting mechanism is suggested to involve the “zwitterionic” species. ► DFT calculations allowed to determine the electroactive species. ► An original grafting mechanism is proposed. - Abstract: Glassy carbon (GC) electrode surfaces are functionalized through electrochemical assisted grafting, in oxidation regime, of six amino acids (AA): β-alanine (β-Ala), L-aspartic acid (Asp), 11-aminoundecanoic acid (UA), 4-aminobenzoic acid (PABA), 4-(4-amino-phenyl)-butyric acid (PFB), 3-(4-amino-phenyl)-propionic acid (PFP). Thus, a GC/AA interface is produced featuring carboxylic groups facing the solution. Electrochemical (cyclic voltammetry and electrochemical impedance spectroscopy) and XPS techniques are used to experimentally characterize the grafting process and the surface state. The theoretical results are compared with the experimental evidence to determine, at a molecular level, the overall grafting mechanism. Ionization potentials, standard oxidation potentials, HOMO and electron spin distributions are calculated at the CCD/6-31G* level of the theory. The comparison of experimental and theoretical data suggests that the main electroactive species is the “zwitterionic” form for the three aliphatic amino acids, while the amino acids featuring the amino group bound to the phenyl aromatic moiety show a different behaviour. The comparison between experimental and theoretical results suggests that both the neutral and the zwitterionic forms are present in the acetonitrile solution in the case of 4-(4-amino-phenyl)-butyric acid (PFB) and 3-(4-amino-phenyl)-propionic acid.

THE THEORETICAL AND METHODICAL APPROACH TO AN ASSESSMENT OF A LEVEL OF DEVELOPMENT OF THE ENTERPRISE IN CONDITIONS OF GLOBALIZATION

Directory of Open Access Journals (Sweden)

Tatiana Shved

2016-11-01

Full Text Available The subject of this article is theoretical, methodical and practical aspects of enterprise development in conditions of globalization. The purpose of this research is to provide theoretical and methodical approach to an assessment of a level of development of the enterprise, which is based on the relationship between the factors and influence, illustrating the effect of the internal and external environment of enterprises functioning, and indicates the level of development of the enterprise. Methodology. Theoretical basis of the study was the examination and rethinking of the main achievements of world and domestic science on the development of enterprises. To achieve the objectives of the research following methods were used: systemic and structural analysis for the formation of methodical approaches to the selection of the factors, influencing the development of enterprises; abstract and logical – for the formulation of conclusions and proposals; the method of valuation and expert assessments to the implementation of the proposed theoretical and methodical approach to an assessment of a level of development of the enterprise in conditions of globalization. Results of the research is the proposed theoretical and methodical to an assessment of a level of development of the enterprise in conditions of globalization, which is associated with the idea of development of the enterprise as a system with inputs–factors, influencing on the development , and outputs – indicators of the level of enterprise development within these factors. So, the chosen factors – resources, financial-economic activity, innovation and investment activities, competition, government influence, and foreign trade. Indicators that express these factors, are capital productivity, labour productivity, material efficiency within the first factor; the profitability of the activity, the coefficient of current assets, the total liquidity coefficient, financial stability

Progress report for a research program in theoretical high-energy physics

International Nuclear Information System (INIS)

Feldman, D.; Fried, H.M.; Jevicki, A.; Kang, K.; Tan, C.I.

1983-01-01

This year research has dealt with a wide range of topics in High-Energy Theoretical Physics. New results have been reached in: geometric structures of symmetry breaking, contracted symmetry groups; continuum strong-coupling methods, fermions in the quenched approximation, treatment of isotopic (color) degrees of freedom, field-theoretic methods for turbulence; axioms and the naturalness of the U(1) symmetry, automatic and color anomalous U(1) symmetries, monopoles and constraints on grand unified model; numerical methods for large N theories, loop-space dynamics, quantum gravity, duality transformations in -models and supergravity; the physical basis of the Adler-Bell-Jackiw anomaly, continuum limit of quantum lattice gravity; electron localization in external magnetic fields; large N phase diagrams and universality, variational methods for studying phase transitions in lattice gauge theories, large-N QCD with matter fields present; valence approximation to lattice QCD, Monte-Carlo evaluation of hadron masses. Much effort has been expended by the members of our group in numerical, computer-augmented calculations, and large-N gauge theories, lattice QCD, fermions and chiral-symmetry breaking. New areas such as quantum gravity, supergravity, and supersymmetry have also geen approached

The Role of Perceived In-group Moral Superiority in Reparative Intentions and Approach Motivation

Directory of Open Access Journals (Sweden)

Zsolt P. Szabó

2017-05-01

Full Text Available Three studies examined how members of a national group react to in-group wrongdoings. We expected that perceived in-group moral superiority would lead to unwillingness to repair the aggression. We also expected that internal-focused emotions such as group-based guilt and group-based shame would predict specific, misdeed-related reparative intentions but not general approach motivation toward the victim groups. In Study 1, facing the in-group’s recent aggression, participants who believed that the Hungarians have been more moral throughout their history than members of other nations, used more exonerating cognitions, experienced less in-group critical emotions and showed less willingness to provide reparations for the members of the victim group. Study 2 and Study 3 confirmed most findings of Study 1. Perceived in-group moral superiority directly or indirectly reduced willingness to provide either general or specific reparations, while internally focused in-group critical emotions predicted specific misdeed-related reparative intentions but not general approach motivation. The role of emotional attachment to the in-group is considered.

Description of group-theoretical model of developed turbulence

International Nuclear Information System (INIS)

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.

Exploring the Impact of Students' Learning Approach on Collaborative Group Modeling of Blood Circulation

Science.gov (United States)

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…

δ-Cut Decision-Theoretic Rough Set Approach: Model and Attribute Reductions

Directory of Open Access Journals (Sweden)

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.

A 3-Component Approach Incorporating Focus Groups in Strategic Planning for Sexual Violence Prevention.

Science.gov (United States)

Cruz, Theresa H; Hess, Julia Meredith; Woelk, Leona; Bear, Samantha

2016-01-01

Sexual violence is of special concern in New Mexico because of the presence of large priority populations in which its prevalence is high. This article describes a 3-component approach to developing a strategic plan to prevent sexual violence in the state that consisted of an advisory group, subject matter experts, and focus groups from geographically and demographically diverse communities. Both common and community-specific themes emerged from the focus groups and were included in the strategic plan. By incorporating community needs and experiences, this approach fosters increased investment in plan implementation.

An Approach to Supervision for Doctoral and Entry-Level Group Counseling Students

Science.gov (United States)

Walsh, Robyn; Bambacus, Elizabeth; Gibson, Donna

2017-01-01

The purpose of this article is to provide a supervision approach to experiential groups that replaces professors with doctoral students in the chain of supervision, enlists a faculty member to provide supervision of supervision to the doctoral students, and translates supervision theory to meet the unique needs of group counseling supervision.…

New approach to the adjustment of group cross sections fitting integral measurements - 2

International Nuclear Information System (INIS)

Chao, Y.A.

1980-01-01

The method developed in the first paper concerning group cross sections fitting integral measurements is generalized to cover the case when the source of the extracted negligence discrepancy cannot be identified and the theoretical relation between the integral and differential measurements is also subject to uncertainty. The question of how to divide in such a case the negligence discrepancy between the integral and differential data is resolved. Application to a specific problem with real experimental data is shown as a demonstration of the method. 4 refs

Non commutative geometry methods for group C{sup *}-algebras

Energy Technology Data Exchange (ETDEWEB)

Diep, Do Ngoc

1996-09-01

This book is intended to provide a quick introduction to the subject. The exposition is scheduled in the sequence, as possible for more understanding for beginners. The author exposed a K-theoretic approach to study group C{sup *}-algebras: started in the elementary part, with one example of description of the structure of C{sup *}-algebra of the group of affine transformations of the real straight line, continued then for some special classes of solvable and nilpotent Lie groups. In the second advanced part, he introduced the main tools of the theory. In particular, the conception of multidimensional geometric quantization and the index of group C{sup *}-algebras were created and developed. (author). Refs.

Basic echocardiography for undergraduate students: a comparison of different peer-teaching approaches.

Science.gov (United States)

Gradl-Dietsch, G; Menon, A K; Gürsel, A; Götzenich, A; Hatam, N; Aljalloud, A; Schrading, S; Hölzl, F; Knobe, M

2018-02-01

The aim of this study was to assess the impact of different teaching interventions in a peer-teaching environment on basic echocardiography skills and to examine the influence of gender on learning outcomes. We randomly assigned 79 s year medical students (55 women, 24 men) to one of four groups: peer teaching (PT), peer teaching using Peyton's four-step approach (PPT), team based learning (TBL) and video-based learning (VBL). All groups received theoretical and practical hands-on training according to the different approaches. Using a pre-post-design we assessed differences in theoretical knowledge [multiple choice (MC) exam], practical skills (Objective Structured Practical Examination, OSPE) and evaluation results with respect to gender. There was a significant gain in theoretical knowledge for all students. There were no relevant differences between the four groups regarding the MC exam and OSPE results. The majority of students achieved good or very good results. Acceptance of the peer-teaching concept was moderate and all students preferred medical experts to peer tutors even though the overall rating of the instructors was fairly good. Students in the Video group would have preferred a different training method. There was no significant effect of gender on evaluation results. Using different peer-teaching concepts proved to be effective in teaching basic echocardiography. Gender does not seem to have an impact on effectiveness of the instructional approach. Qualitative analysis revealed limited acceptance of peer teaching and especially of video-based instruction.

Nonperturbative Renormalization Group Approach to Polymerized Membranes

Science.gov (United States)

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.

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

African Journals Online (AJOL)

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 ...

Group Dynamics and Individual Roles: A Differentiated Approach to Social-Emotional Learning

Science.gov (United States)

Dugas, Daryl

2017-01-01

Differentiated instruction is a set of strategies to help teachers meet each child where he or she is in order to improve students' engagement, lead them to do their best work, and maximize their success. This article describes a differentiated classroom management approach based in group dynamics which focuses on the development of group norms…

A dual approach to IS strategy

DEFF Research Database (Denmark)

Ivang, Reimer

2014-01-01

This paper discusses IS strategising and how the combination of the planning and the incremental approaches can enable successful IS strategising. IS strategising is conceptualised as a dual organisational process in which the network and the hierarchy positively coexist through group-learning pr......This paper discusses IS strategising and how the combination of the planning and the incremental approaches can enable successful IS strategising. IS strategising is conceptualised as a dual organisational process in which the network and the hierarchy positively coexist through group......-learning processes. The findings from two case studies illustrate the theoretical framework. An analysis of 28 interviews reveal the complexity of IS strategising and show that IS strategising is best understood as a dual dynamic-interactive processing which the choice of strategic approach is not a dichotomy...

Theoretical Fundamentals of Human Factor

OpenAIRE

Nicoleta Maria Ienciu

2012-01-01

The purpose of this paper is to identify the theoretical approaches presented by the literature on the human factor. In order to achieve such objective we have performed a qualitative research by analyzing the content of several papers published in internationally renowned journals, classified according to the list of journals' ranking provided by the Association of Business Schools (UK), in relation to the theories that have been approached within it. Our findings suggest that from all ident...

Toward a qualitative understanding of binge-watching behaviors: A focus group approach.

Science.gov (United States)

Flayelle, Maèva; Maurage, Pierre; Billieux, Joël

2017-12-01

Background and aims Binge-watching (i.e., seeing multiple episodes of the same TV series in a row) now constitutes a widespread phenomenon. However, little is known about the psychological factors underlying this behavior, as reflected by the paucity of available studies, most merely focusing on its potential harmfulness by applying the classic criteria used for other addictive disorders without exploring the uniqueness of binge-watching. This study thus aimed to take the opposite approach as a first step toward a genuine understanding of binge-watching behaviors through a qualitative analysis of the phenomenological characteristics of TV series watching. Methods A focus group of regular TV series viewers (N = 7) was established to explore a wide range of aspects related to TV series watching (e.g., motives, viewing practices, and related behaviors). Results A content analysis identified binge-watching features across three dimensions: TV series watching motivations, TV series watching engagement, and structural characteristics of TV shows. Most participants acknowledged that TV series watching can become addictive, but they all agreed having trouble recognizing themselves as truly being an "addict." Although obvious connections could be established with substance addiction criteria and symptoms, such parallelism appeared to be insufficient, as several distinctive facets emerged (e.g., positive view, transient overinvolvement, context dependency, and low everyday life impact). Discussion and conclusion The research should go beyond the classic biomedical and psychological models of addictive behaviors to account for binge-watching in order to explore its specificities and generate the first steps toward an adequate theoretical rationale for these emerging problematic behaviors.

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

Directory of Open Access Journals (Sweden)

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.

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

International Nuclear Information System (INIS)

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

A theoretical approach to dual practice regulations in the health sector.

Science.gov (United States)

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.

Rock mechanics site descriptive model-theoretical approach. Preliminary site description Forsmark area - version 1.2

Energy Technology Data Exchange (ETDEWEB)

Fredriksson, Anders; Olofsson, Isabelle [Golder Associates AB, Uppsala (Sweden)

2005-12-15

The present report summarises the theoretical approach to estimate the mechanical properties of the rock mass in relation to the Preliminary Site Descriptive Modelling, version 1.2 Forsmark. The theoretical approach is based on a discrete fracture network (DFN) description of the fracture system in the rock mass and on the results of mechanical testing of intact rock and on rock fractures. To estimate the mechanical properties of the rock mass a load test on a rock block with fractures is simulated with the numerical code 3DEC. The location and size of the fractures are given by DFN-realisations. The rock block was loaded in plain strain condition. From the calculated relationship between stresses and deformations the mechanical properties of the rock mass were determined. The influence of the geometrical properties of the fracture system on the mechanical properties of the rock mass was analysed by loading 20 blocks based on different DFN-realisations. The material properties of the intact rock and the fractures were kept constant. The properties are set equal to the mean value of each measured material property. The influence of the variation of the properties of the intact rock and variation of the mechanical properties of the fractures are estimated by analysing numerical load tests on one specific block (one DFN-realisation) with combinations of properties for intact rock and fractures. Each parameter varies from its lowest values to its highest values while the rest of the parameters are held constant, equal to the mean value. The resulting distribution was expressed as a variation around the value determined with mean values on all parameters. To estimate the resulting distribution of the mechanical properties of the rock mass a Monte-Carlo simulation was performed by generating values from the two distributions independent of each other. The two values were added and the statistical properties of the resulting distribution were determined.

Rock mechanics site descriptive model-theoretical approach. Preliminary site description Forsmark area - version 1.2

International Nuclear Information System (INIS)

Fredriksson, Anders; Olofsson, Isabelle

2005-12-01

The present report summarises the theoretical approach to estimate the mechanical properties of the rock mass in relation to the Preliminary Site Descriptive Modelling, version 1.2 Forsmark. The theoretical approach is based on a discrete fracture network (DFN) description of the fracture system in the rock mass and on the results of mechanical testing of intact rock and on rock fractures. To estimate the mechanical properties of the rock mass a load test on a rock block with fractures is simulated with the numerical code 3DEC. The location and size of the fractures are given by DFN-realisations. The rock block was loaded in plain strain condition. From the calculated relationship between stresses and deformations the mechanical properties of the rock mass were determined. The influence of the geometrical properties of the fracture system on the mechanical properties of the rock mass was analysed by loading 20 blocks based on different DFN-realisations. The material properties of the intact rock and the fractures were kept constant. The properties are set equal to the mean value of each measured material property. The influence of the variation of the properties of the intact rock and variation of the mechanical properties of the fractures are estimated by analysing numerical load tests on one specific block (one DFN-realisation) with combinations of properties for intact rock and fractures. Each parameter varies from its lowest values to its highest values while the rest of the parameters are held constant, equal to the mean value. The resulting distribution was expressed as a variation around the value determined with mean values on all parameters. To estimate the resulting distribution of the mechanical properties of the rock mass a Monte-Carlo simulation was performed by generating values from the two distributions independent of each other. The two values were added and the statistical properties of the resulting distribution were determined

Field theoretical approach to proton-nucleus reactions. I - One step inelastic scattering

International Nuclear Information System (INIS)

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

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

Science.gov (United States)

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.

Theoretical foundations of electron spin resonance

CERN Document Server

Harriman, John E

2013-01-01

Theoretical Foundations of Electron Spin Resonance deals with the theoretical approach to electron paramagnetic resonance. The book discusses electron spin resonance in applications related to polyatomic, probably organic, free radicals in condensed phases. The book also focuses on essentially static phenomena, that is, the description and determination of stationary-state energy levels. The author reviews the Dirac theory of the electron in which a four-component wave function is responsible for the behavior of the electron. The author then connects this theory with the nonrelativistic wave f

Theoretical Mathematics

Science.gov (United States)

Stöltzner, Michael

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

Certain number-theoretic episodes in algebra

CERN Document Server

Sivaramakrishnan, R

2006-01-01

Many basic ideas of algebra and number theory intertwine, making it ideal to explore both at the same time. Certain Number-Theoretic Episodes in Algebra focuses on some important aspects of interconnections between number theory and commutative algebra. Using a pedagogical approach, the author presents the conceptual foundations of commutative algebra arising from number theory. Self-contained, the book examines situations where explicit algebraic analogues of theorems of number theory are available. Coverage is divided into four parts, beginning with elements of number theory and algebra such as theorems of Euler, Fermat, and Lagrange, Euclidean domains, and finite groups. In the second part, the book details ordered fields, fields with valuation, and other algebraic structures. This is followed by a review of fundamentals of algebraic number theory in the third part. The final part explores links with ring theory, finite dimensional algebras, and the Goldbach problem.

The value chain of a commune as an attempt to integrate various theoretical concepts

OpenAIRE

Dziemianowicz Wojciech

2016-01-01

This article deals with the topic of the local development factors within the value chain of the commune (gmina). The concept of the value chain examines development factors in three groups: the leader, the internal environment and the external environment; it also takes into account the time factor. This article also presents the usefulness of three theoretical and conceptual approaches in reference to the idea of the value chain: the theory of development path dependency, the network theory...

Using a Systematic Approach and Theoretical Framework to Design a Curriculum for the Shaping Healthy Choices Program.

Science.gov (United States)

Linnell, Jessica D; Zidenberg-Cherr, Sheri; Briggs, Marilyn; Scherr, Rachel E; Brian, Kelley M; Hillhouse, Carol; Smith, Martin H

2016-01-01

To examine the use of a systematic approach and theoretical framework to develop an inquiry-based, garden-enhanced nutrition curriculum for the Shaping Healthy Choices Program. Curriculum development occurred in 3 steps: identification of learning objectives, determination of evidence of learning, and activity development. Curriculum activities were further refined through pilot-testing, which was conducted in 2 phases. Formative data collected during pilot-testing resulted in improvements to activities. Using a systematic, iterative process resulted in a curriculum called Discovering Healthy Choices, which has a strong foundation in Social Cognitive Theory and constructivist learning theory. Furthermore, the Backward Design method provided the design team with a systematic approach to ensure activities addressed targeted learning objectives and overall Shaping Healthy Choices Program goals. The process by which a nutrition curriculum is developed may have a direct effect on student outcomes. Processes by which nutrition curricula are designed and learning objectives are selected, and how theory and pedagogy are applied should be further investigated so that effective approaches to developing garden-enhanced nutrition interventions can be determined and replicated. Copyright © 2016 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Theoretical Division annual report, FY 1975. [LASL

Energy Technology Data Exchange (ETDEWEB)

Carruthers, P.A.

1976-02-01

This report presents an overview of the activities in the Theoretical Division and a summary of research highlights during FY 1975. It is intended to inform a wide audience about the theoretical work of the LASL and, therefore, contains introductory material which places recent advances in a broader context. The report is organized into two special interest reports: reactor safety research and the Advanced Research Committee, and 11 reports from the T-Division group leaders on the work of their respective groups. Main interests and responsibilities are outlined including the relationship of the group's work to the work of other T-Division groups and other divisions at the Laboratory. The description of research highlights for FY 1975 explains in a fairly simple, straightforward manner the major recent advances and their significance. Each group report is followed by a publication list for FY 1975 (330 references) and a list of talks given outside the Laboratory (140 references). 29 figures. (auth)

Task group of international union of radioecology 'ecosystem approach to environment protection'

International Nuclear Information System (INIS)

Fuma, Shoichi

2011-01-01

An ecosystem approach is a holistic (i.e., top-down) strategy for protection of ecosystem structures and functions from perturbations. A task group of International Union of Radioecology 'Ecosystem Approach to Environment Protection' was launched in April, 2010. This task group is preparing a report on the following topics: (1) goals of environmental protection; (2) legislation about environmental protection; (3) assessment of the Reference Animals and Plants (RAP) concept in the general context of environmental protection; (4) limitations and uncertainties of the RAPs concept; (5) justification and merits of the ecosystem approach; (6) assessing the feasibility of the ecosystem approach; (7) research and development required for the ecosystem approach; and (8) recommendations with respect to radiation protection. The topics 1, 3, 4 and 5 have been almost completely prepared, and demonstrate that the ecosystem approach is required for radiation protection of the environment. On the other hand, methods of the ecosystem approach which should be adopted for radiation protection of the environment are not clear in the current draft report. They should be specified by reviewing the Convention on Biological Diversity, fish stock management and other activities where the ecosystem approach is already adopted. (author)

[Family groups in nursing graduation teaching practice].

Science.gov (United States)

de Assis, Aisllan Diego; da Silva, Priscila Patrícia; Claudino, Talita Xavier; de Oliveira, Alice Guimarães Bottaro

2010-09-01

The centers of psychosocial care (CAPS, acronym in Portuguese) are strategic devices for mental health care currently available in Brazil. Nurses are professionals required to compose the minimum staff of this device, which values the group activities involving users. This study presents a report of the experience of nursing undergraduates from Universidade Federal do Mato Grosso (UFMT) on their conducting waiting-room group sessions with relatives of users of a CAPS from Cuiabá, Mato Grosso state. This experience is justified by the fact that nursing students have few opportunities to develop group approach abilities during their graduation course, which focuses mainly on clinical individual care. The aim of the experience was to provide theoretical-practical learning of all the work stages of group work: recognizing the need and possibility of conducting the activity, planning, coordination and group evaluation. The results confirm the need and possibility of performing group experiences in mental health care and in nursing education.

Demystifying Theoretical Sampling in Grounded Theory Research

Directory of Open Access Journals (Sweden)

Jenna Breckenridge BSc(Hons,Ph.D.Candidate

2009-06-01

Full Text Available Theoretical sampling is a central tenet of classic grounded theory and is essential to the development and refinement of a theory that is ‘grounded’ in data. While many authors appear to share concurrent definitions of theoretical sampling, the ways in which the process is actually executed remain largely elusive and inconsistent. As such, employing and describing the theoretical sampling process can present a particular challenge to novice researchers embarking upon their first grounded theory study. This article has been written in response to the challenges faced by the first author whilst writing a grounded theory proposal. It is intended to clarify theoretical sampling for new grounded theory researchers, offering some insight into the practicalities of selecting and employing a theoretical sampling strategy. It demonstrates that the credibility of a theory cannot be dissociated from the process by which it has been generated and seeks to encourage and challenge researchers to approach theoretical sampling in a way that is apposite to the core principles of the classic grounded theory methodology.

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

International Nuclear Information System (INIS)

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

Do pseudo-absence selection strategies influence species distribution models and their predictions? An information-theoretic approach based on simulated data

Directory of Open Access Journals (Sweden)

Guisan Antoine

2009-04-01

Full Text Available Abstract Background Multiple logistic regression is precluded from many practical applications in ecology that aim to predict the geographic distributions of species because it requires absence data, which are rarely available or are unreliable. In order to use multiple logistic regression, many studies have simulated "pseudo-absences" through a number of strategies, but it is unknown how the choice of strategy influences models and their geographic predictions of species. In this paper we evaluate the effect of several prevailing pseudo-absence strategies on the predictions of the geographic distribution of a virtual species whose "true" distribution and relationship to three environmental predictors was predefined. We evaluated the effect of using a real absences b pseudo-absences selected randomly from the background and c two-step approaches: pseudo-absences selected from low suitability areas predicted by either Ecological Niche Factor Analysis: (ENFA or BIOCLIM. We compared how the choice of pseudo-absence strategy affected model fit, predictive power, and information-theoretic model selection results. Results Models built with true absences had the best predictive power, best discriminatory power, and the "true" model (the one that contained the correct predictors was supported by the data according to AIC, as expected. Models based on random pseudo-absences had among the lowest fit, but yielded the second highest AUC value (0.97, and the "true" model was also supported by the data. Models based on two-step approaches had intermediate fit, the lowest predictive power, and the "true" model was not supported by the data. Conclusion If ecologists wish to build parsimonious GLM models that will allow them to make robust predictions, a reasonable approach is to use a large number of randomly selected pseudo-absences, and perform model selection based on an information theoretic approach. However, the resulting models can be expected to have

Responsible Practices are Culturally Embedded: Theoretical Considerations on Industry-Specific Corporate Social Responsibility

OpenAIRE

Beschorner, Thomas; Hajduk, Thomas

2017-01-01

In this paper, we develop our argument in three steps: Firstly, we elaborate on some theoretical perspectives for industry-specific CSR by referring to cultural business ethics, a theoretical approach which is located between purely business perspectives and purely normative perspectives on CSR. Secondly, we briefly introduce the papers of this special issue, which covers a wide range of theoretical approaches and empirical studies in the field of industry-specific CSR. Thirdly, we draw atten...

Partnership of power and business: european approaches and conceptions

OpenAIRE

Serhii Andriiovych Kvitka

2013-01-01

The article reviews the most common European scientific concept of interaction between government and business. On this basis, the analysis of the main achievements and shortcomings of theoretical and methodological approaches to the study of business as a political actor. Interest groups and pressure groups are a form of protective groups that influence the actions of the modern authorities, both in Europe and in Ukraine . In terms of pluralism, society is composed of a large num...

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

International Nuclear Information System (INIS)

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.)

Predicting maintenance of attendance at walking groups: testing constructs from three leading maintenance theories.

Science.gov (United States)

Kassavou, Aikaterini; Turner, Andrew; Hamborg, Thomas; French, David P

2014-07-01

Little is known about the processes and factors that account for maintenance, with several theories existing that have not been subject to many empirical tests. The aim of this study was to test how well theoretical constructs derived from the Health Action Process Approach, Rothman's theory of maintenance, and Verplanken's approach to habitual behavior predicted maintenance of attendance at walking groups. 114 participants, who had already attended walking groups in the community for at least 3 months, completed a questionnaire assessing theoretical constructs regarding maintenance. An objective assessment of attendance over the subsequent 3 months was gained. Multilevel modeling was used to predict maintenance, controlling for clustering within walking groups. Recovery self-efficacy predicted maintenance, even after accounting for clustering. Satisfaction with social outcomes, satisfaction with health outcomes, and overall satisfaction predicted maintenance, but only satisfaction with health outcomes significantly predicted maintenance after accounting for clustering. Self-reported habitual behavior did not predict maintenance despite mean previous attendance being 20.7 months. Recovery self-efficacy, and satisfaction with health outcomes of walking group attendance appeared to be important for objectively measured maintenance, whereas self-reported habit appeared not to be important for maintenance at walking groups. The findings suggest that there is a need for intervention studies to boost recovery self-efficacy and satisfaction with outcomes of walking group attendance, to assess impact on maintenance.

The unitary-group formulation of quantum chemistry

International Nuclear Information System (INIS)

Campbell, L.L.

1990-01-01

The major part of this dissertation establishes group theoretical techniques that are applicable to the quantum-mechanical many-body atomic and molecular problems. Several matrix element evaluation methods for many-body states are developed. The generator commutation method using generator states is presented for the first time as a complete algorithm, and a computer implementation of the method is developed. A major result of this work is the development of a new method of calculation called the freeon tensor product (FTP) method. This method is much simpler and for many purposes superior to the GUGA procedure (graphical unitary group approach), widely used in configuration interaction calculations. This dissertation is also concerned with the prediction of atomic spectra. In principle spectra can be computed by the methods of ab initio quantum chemistry. In practice these computations are difficult, expensive, time consuming, and not uniformly successful. In this dissertation, the author employs a semi-empirical group theoretical analysis of discrete spectra is the exact analog of the Fourier analysis of continuous functions. In particular, he focuses on the spectra of atoms with incomplete p, d, and f shells. The formulas and techniques are derived in a fashion that apply equally well for more complex systems, as well as the isofreeon model of spherical nuclei

Theoretical aspects of strategic adaptation management of enterprises

Directory of Open Access Journals (Sweden)

Khaustova Ksenya Mykhailivna

2016-09-01

Full Text Available In the article the theoretical foundations of strategic adaptation management as an actual approach to the management of enterprise under conditions that are constantly changing have been developed. The theoretical approaches to the definition of “adaptation enterprise” have been studied and systematized. The essence and principles of strategic management adaptation were expounded. The model of strategic management was improved through the introduction of continuous monitoring and evaluation of changes in the environment and the actual adjustments to the system and processes. The essence and features adaptive capacity of the enterprise as a key element of strategic management have been investigated.

Field-theoretic approach to fluctuation effects in neural networks

International Nuclear Information System (INIS)

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

Breaking the theoretical scaling limit for predicting quasiparticle energies: the stochastic GW approach.

Science.gov (United States)

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.

Managerial Leadership - A Theoretical Approach

Directory of Open Access Journals (Sweden)

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.

Identifying target groups for environmentally sustainable transport: assessment of different segmentation approaches

DEFF Research Database (Denmark)

Haustein, Sonja; Hunecke, Marcel

2013-01-01

Recently, the use of attitude-based market segmentation to promote environmentally sustainable transport has significantly increased. The segmentation of the population into meaningful groups sharing similar attitudes and preferences provides valuable information about how green measures should...... and behavioural segmentations are compared regarding marketing criteria. Although none of the different approaches can claim absolute superiority, attitudinal approaches show advantages in providing startingpoints for interventions to reduce car use....

Social Identity and Group Contests

OpenAIRE

Zaunbrecher, Henrik; Riedl, Arno

2016-01-01

Social identity has been shown to successfully enhance cooperation and effort in cooperation and coordination games. Little is known about the causal effect of social identity on the propensity to engage in group conflict. In this paper we explore theoretically and experimentally whether social identity increases investments in group contests. We show theoretically that increased social identity with the own group implies higher investments in Tullock contests. Empirically we find that induce...

Prospecting theoretical approaches to understand internationalization of creative economy firms

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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.

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

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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.

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

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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

Data, Methods, and Theoretical Implications

Science.gov (United States)

Hannagan, Rebecca J.; Schneider, Monica C.; Greenlee, Jill S.

2012-01-01

Within the subfields of political psychology and the study of gender, the introduction of new data collection efforts, methodologies, and theoretical approaches are transforming our understandings of these two fields and the places at which they intersect. In this article we present an overview of the research that was presented at a National…

Theoretical analysis of heat transfer in, and electrical performance of, a milliwatt radioisotopic powered thermoelectric generator

International Nuclear Information System (INIS)

Biver, C.J.

1975-01-01

A simplified, theoretical model has been made for a radioisotope-powered milliwatt thermoelectric generator (RTG). Calculations of unit heat transfer and electrical performance characteristics are made in two ways: (a) using discrete values of input physical parameters for an individual unit; and (b) using a statistical simulation (Monte Carlo) approach for estimating the variation in performance in a group of N-units. The statistical simulation approach is useful in: (a) estimating the allowable range of input parameters conducive to the production design meeting specifications in a group of N-units; and (b) determining particular parameters that must be significantly restricted in variation to achieve desired performance. The available experimental data, as compared with the discrete value calculations, are in quite good agreement (within 5 percent generally). (U.S.)

Theoretical analysis of two ACO approaches for the traveling salesman problem

DEFF Research Database (Denmark)

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...

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

Directory of Open Access Journals (Sweden)

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.

The Role of Perceived In-group Moral Superiority in Reparative Intentions and Approach Motivation

OpenAIRE

Szabó, Zsolt P.; Mészáros, Noémi Z.; Csertő, István

2017-01-01

Three studies examined how members of a national group react to in-group wrongdoings. We expected that perceived in-group moral superiority would lead to unwillingness to repair the aggression. We also expected that internal-focused emotions such as group-based guilt and group-based shame would predict specific, misdeed-related reparative intentions but not general approach motivation toward the victim groups. In Study 1, facing the in-group’s recent aggression, participants who believed that...

Dialogic feedforward in group coaching

DEFF Research Database (Denmark)

Alrø, Helle; Dahl, Poul Nørgård

2015-01-01

The overall purpose of the article is to describe a joint learning process where both practicable and theoretically anchored knowledge are in the foreground. The empirical data derives from an EU project. In focus is a group of course leaders and their experiences of carrying out a training...... programme targeted for a group of individuals with a weak position on the labour market. The author brings out what happens when individuals try to understand perspectives from one another. The results demonstrate the knowledge that is developed when members of a project team are included in the entire...... research process, from the definition of problems to the analysis, presentation of results and suggestions of change. Further the outcome illustrates how an interactive research approach can be conducted in close co-operation with those concerned. Active participation, a structured learning process...

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

International Nuclear Information System (INIS)

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

Photodynamic therapy: Theoretical and experimental approaches to dosimetry

Science.gov (United States)

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

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

Directory of Open Access Journals (Sweden)

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 �

Developing hybrid approaches to predict pKa values of ionizable groups

Science.gov (United States)

Witham, Shawn; Talley, Kemper; Wang, Lin; Zhang, Zhe; Sarkar, Subhra; Gao, Daquan; Yang, Wei

2011-01-01

Accurate predictions of pKa values of titratable groups require taking into account all relevant processes associated with the ionization/deionization. Frequently, however, the ionization does not involve significant structural changes and the dominating effects are purely electrostatic in origin allowing accurate predictions to be made based on the electrostatic energy difference between ionized and neutral forms alone using a static structure. On another hand, if the change of the charge state is accompanied by a structural reorganization of the target protein, then the relevant conformational changes have to be taken into account in the pKa calculations. Here we report a hybrid approach that first predicts the titratable groups, which ionization is expected to cause conformational changes, termed “problematic” residues, then applies a special protocol on them, while the rest of the pKa’s are predicted with rigid backbone approach as implemented in multi-conformation continuum electrostatics (MCCE) method. The backbone representative conformations for “problematic” groups are generated with either molecular dynamics simulations with charged and uncharged amino acid or with ab-initio local segment modeling. The corresponding ensembles are then used to calculate the pKa of the “problematic” residues and then the results are averaged. PMID:21744395

Advances in neural networks computational and theoretical issues

CERN Document Server

Esposito, Anna; Morabito, Francesco

2015-01-01

This book collects research works that exploit neural networks and machine learning techniques from a multidisciplinary perspective. Subjects covered include theoretical, methodological and computational topics which are grouped together into chapters devoted to the discussion of novelties and innovations related to the field of Artificial Neural Networks as well as the use of neural networks for applications, pattern recognition, signal processing, and special topics such as the detection and recognition of multimodal emotional expressions and daily cognitive functions, and  bio-inspired memristor-based networks.  Providing insights into the latest research interest from a pool of international experts coming from different research fields, the volume becomes valuable to all those with any interest in a holistic approach to implement believable, autonomous, adaptive, and context-aware Information Communication Technologies.

Group theoretical arguments on the Landau theory of second-order phase transitions applied to the phase transitions in some liquid crystals

International Nuclear Information System (INIS)

Rosciszewski, K.

1979-01-01

The phase transitions between liquids and several of the simplest liquid crystalline phases (nematic, cholesteric, and the simplest types of smectic A and smectic C) were studied from the point of view of the group-theoretical arguments of Landau theory. It was shown that the only possible candidates for second-order phase transitions are those between nematic and smectic A, between centrosymmetric nematic and smectic C and between centrosymmetric smectic A and smectic C. Simple types of density functions for liquid crystalline phases are proposed. (author)

Theoretical aspects of graphene-like group IV semiconductors

International Nuclear Information System (INIS)

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.

Theoretical aspects of graphene-like group IV semiconductors

Energy Technology Data Exchange (ETDEWEB)

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.

Economic growth factors system: theoretical and methodological aspect

OpenAIRE

H.Ya. Hlukha

2014-01-01

The aim of the article. The main objective of the article is to create theoretical grounds to build the system of economic growth factors, to modernize their classification, to define exogenous and endogenous factors, to analyze them within the state economic policy structure. The results of the analysis. The article focuses on economic growth factors theoretical studies: - economic growth factors classification characteristics have been highlighted; - various approaches to determine...

How to make friends: A logical approach to social group creation

NARCIS (Netherlands)

Smets, S.; Velázquez-Quesada, F.R.; Baltag, A.; Seligman, J.; Yamada, T.

2017-01-01

This paper studies the logical features of social group creation. We focus on the mechanisms which indicate when agents can form a team based on the correspondence in their set of features (behavior, opinions, etc.). Our basic approach uses a semi-metric on the set of agents, which is used to

The Effect of Integrated Learning-Teaching Approach on Reading Comprehension and Narration Skills

Directory of Open Access Journals (Sweden)

Ergün Hamzadayı

2010-12-01

Full Text Available This study investigated the effects of integrated learning-teaching approach on reading comprehension and narration skills. Considerations regarding how to overcome difficulties in the teaching of Turkish language through multi-theoretical perspectives have resulted in this approach to come into the existence. For the purpose of forming theoretical foundations of the research, behaviourist, cognitive and constructivist learning theories with their philosophical foundations were introduced, their principals and assumptions with regard to instructional design were compared, and their strengths and weakness were delineated. These considerations were then associated with the components of Turkish language program (content, objectives, teaching strategies and methods, assessment and that paved way for “integrative learning and teaching approach” to come into being. This study aimed to investigate whether there is a significant difference between the performance of the experimental group students who were exposed to integrative learning and teaching approach and that of control group students who were not exposed to integrative learning and teaching approach in terms of reading comprehension and written expression skills in Turkish language

Consensus clustering approach to group brain connectivity matrices

Directory of Open Access Journals (Sweden)

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.

[Health, environment and nursing. Philosophical and theoretical foundations for the development and validation of a nursing interface terminology. Part III].

Science.gov (United States)

Juvé-Udina, Maria-Eulàlia

2012-06-01

This manuscript is the third of a triad of papers introducing the philosophical and theoretical approaches that support the development and validation of a nursing interface terminology as a standard vocabulary designed to ease data entry into electronic health records, to produce information and to generate knowledge. To analyze the philosophical and theoretical approaches considered in the development of a new nursing interface terminology called ATIC. Review, analysis and discussion of the main philosophical orientations, high and mid-range theories and nursing scientific literature to develop an interpretative conceptualization of the metaparadigm concepts "Health", "Environment" and "Nursing". In the 2 previous papers the ATIC terminology, its foundation on pragmatism, holism, post-positivism and constructivism and the construction of the meaning for the concept elndividualh is discussed. In this third paper, Health is conceptualized as a multidimensional balance state and the concepts of Partial health status, Disease and Being ill are explored within. The analysis of the Environment theories drives its conceptualization as a group of variables that has the potential to affect health status. In this orientation, Nursing is understood as the scientific discipline focused on the study of health status in the particular environment and experience of the individuals, groups, communities or societies. ATIC terminology is rooted on an eclectic philosophical and theoretical foundation, allowing it to be used from different trends within the totality paradigm.

BLIG: A New Approach for Sensor Identification, Grouping,and Authorisation in Body Sensor Networks

DEFF Research Database (Denmark)

Andersen, Jacob; Bardram, Jakob Eyvind

2007-01-01

Using body sensor networks (BSN) in critical clinical settings like emergency units in hospitals or in accidents requires that such a network can be deployed, configured, and started in a fast and easy way, while maintaining trust in the network. In this paper we present a novel approach called...... BLIG (Blinking Led Indicated Grouping) for easy deployment of BSNs on patients in critical situations, including mechanisms for uniquely identifying and grouping sensor nodes belonging to a patient in a secure and trusted way. This approach has been designed in close cooperation with users, and easy...

A theoretical approach to the problem of dose-volume constraint estimation and their impact on the dose-volume histogram selection

International Nuclear Information System (INIS)

Schinkel, Colleen; Stavrev, Pavel; Stavreva, Nadia; Fallone, B. Gino

2006-01-01

This paper outlines a theoretical approach to the problem of estimating and choosing dose-volume constraints. Following this approach, a method of choosing dose-volume constraints based on biological criteria is proposed. This method is called ''reverse normal tissue complication probability (NTCP) mapping into dose-volume space'' and may be used as a general guidance to the problem of dose-volume constraint estimation. Dose-volume histograms (DVHs) are randomly simulated, and those resulting in clinically acceptable levels of complication, such as NTCP of 5±0.5%, are selected and averaged producing a mean DVH that is proven to result in the same level of NTCP. The points from the averaged DVH are proposed to serve as physical dose-volume constraints. The population-based critical volume and Lyman NTCP models with parameter sets taken from literature sources were used for the NTCP estimation. The impact of the prescribed value of the maximum dose to the organ, D max , on the averaged DVH and the dose-volume constraint points is investigated. Constraint points for 16 organs are calculated. The impact of the number of constraints to be fulfilled based on the likelihood that a DVH satisfying them will result in an acceptable NTCP is also investigated. It is theoretically proven that the radiation treatment optimization based on physical objective functions can sufficiently well restrict the dose to the organs at risk, resulting in sufficiently low NTCP values through the employment of several appropriate dose-volume constraints. At the same time, the pure physical approach to optimization is self-restrictive due to the preassignment of acceptable NTCP levels thus excluding possible better solutions to the problem

2nd International Conference on Proof-Theoretic Semantics

CERN Document Server

Schroeder-Heister, Peter

2016-01-01

This volume is the first ever collection devoted to the field of proof-theoretic semantics. Contributions address topics including the systematics of introduction and elimination rules and proofs of normalization, the categorial characterization of deductions, the relation between Heyting's and Gentzen's approaches to meaning, knowability paradoxes, proof-theoretic foundations of set theory, Dummett's justification of logical laws, Kreisel's theory of constructions, paradoxical reasoning, and the defence of model theory. The field of proof-theoretic semantics has existed for almost 50 years, but the term itself was proposed by Schroeder-Heister in the 1980s. Proof-theoretic semantics explains the meaning of linguistic expressions in general and of logical constants in particular in terms of the notion of proof. This volume emerges from presentations at the Second International Conference on Proof-Theoretic Semantics in Tübingen in 2013, where contributing authors were asked to provide a self-contained descri...

Group theory approach to scattering

International Nuclear Information System (INIS)

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

The value chain of a commune as an attempt to integrate various theoretical concepts

Directory of Open Access Journals (Sweden)

Dziemianowicz Wojciech

2016-06-01

Full Text Available This article deals with the topic of the local development factors within the value chain of the commune (gmina. The concept of the value chain examines development factors in three groups: the leader, the internal environment and the external environment; it also takes into account the time factor. This article also presents the usefulness of three theoretical and conceptual approaches in reference to the idea of the value chain: the theory of development path dependency, the network theory, and the concept of smart specializations.

The question of representation in the psychoanalytical and cognitive-behavioural approaches. Some theoretical aspects and therapy considerations

Directory of Open Access Journals (Sweden)

Philippe eDe Timary

2011-04-01

Full Text Available This paper compares the cognitive-behavioural and psychoanalytical approaches with respect to the way in which each of them conceives of representation and deals with the issues that this involves. In both of them conscious and latent (unconscious representations play a crucial role. Highlighting similarities and differences facilitate communication on a theoretical level but also prove helpful to the clinical practitioners involved. We try to put forward an attempt at comparison, with the idea of going beyond the -- obviously important -- differences in vocabulary. In this attempt at comparison, we have successively compared the definitions of representation and the respective therapeutic interventions proposed by each approach. There are no doubt many overlapping elements in the way in which the workings of the mind are conceived of in these approaches, particularly as regards their links with affects. We next developed the implications of representation deficits in pathology, suggesting the important role played by elements that are avoided, suppressed from memory or repressed, and with respect to the need to treat such material in a specific manner so as to ensure some progress as to the symptoms presented. We finally summarized common and distinct aspects of the two perspectives. The very fact that two approaches that follow very distinct methodologies reach the same conclusion concerning the importance of distortions and failures of representation in generating mental distress strengthens, in our view, the epistemological reliability of the role of representation in psychopathology.

Theoretical studies of chemical reaction dynamics

Energy Technology Data Exchange (ETDEWEB)

Schatz, G.C. [Argonne National Laboratory, IL (United States)

1993-12-01

This collaborative program with the Theoretical Chemistry Group at Argonne involves theoretical studies of gas phase chemical reactions and related energy transfer and photodissociation processes. Many of the reactions studied are of direct relevance to combustion; others are selected they provide important examples of special dynamical processes, or are of relevance to experimental measurements. Both classical trajectory and quantum reactive scattering methods are used for these studies, and the types of information determined range from thermal rate constants to state to state differential cross sections.

Theoretical information measurement in nonrelativistic time-dependent approach

Science.gov (United States)

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.

The Assessment Methodology RADAR – A Theoretical Approach of a Methodology for Coordinating the Efforts to Improve the Organizational Processes to Achieve Excellence

Directory of Open Access Journals (Sweden)

Cristina Raluca Popescu

2015-05-01

Full Text Available In the paper “The Assessment Methodology RADAR – A Theoretical Approach of a Methodology for Coordinating the Efforts to Improve the Organizational Processes to Achieve Excellence” the authors present the basic features of the assessment methodology RADAR that is designed to coordinate the efforts to improve the organizational processes in order to achieve excellence.

Compendium of theoretical physics

CERN Document Server

Wachter, Armin

2006-01-01

Mechanics, Electrodynamics, Quantum Mechanics, and Statistical Mechanics and Thermodynamics comprise the canonical undergraduate curriculum of theoretical physics. In Compendium of Theoretical Physics, Armin Wachter and Henning Hoeber offer a concise, rigorous and structured overview that will be invaluable for students preparing for their qualifying examinations, readers needing a supplement to standard textbooks, and research or industrial physicists seeking a bridge between extensive textbooks and formula books. The authors take an axiomatic-deductive approach to each topic, starting the discussion of each theory with its fundamental equations. By subsequently deriving the various physical relationships and laws in logical rather than chronological order, and by using a consistent presentation and notation throughout, they emphasize the connections between the individual theories. The reader’s understanding is then reinforced with exercises, solutions and topic summaries. Unique Features: Every topic is ...

Canonical group quantization and boundary conditions

International Nuclear Information System (INIS)

Jung, Florian

2012-01-01

In the present thesis, we study quantization of classical systems with non-trivial phase spaces using the group-theoretical quantization technique proposed by Isham. Our main goal is a better understanding of global and topological aspects of quantum theory. In practice, the group-theoretical approach enables direct quantization of systems subject to constraints and boundary conditions in a natural and physically transparent manner -- cases for which the canonical quantization method of Dirac fails. First, we provide a clarification of the quantization formalism. In contrast to prior treatments, we introduce a sharp distinction between the two group structures that are involved and explain their physical meaning. The benefit is a consistent and conceptually much clearer construction of the Canonical Group. In particular, we shed light upon the 'pathological' case for which the Canonical Group must be defined via a central Lie algebra extension and emphasise the role of the central extension in general. In addition, we study direct quantization of a particle restricted to a half-line with 'hard wall' boundary condition. Despite the apparent simplicity of this example, we show that a naive quantization attempt based on the cotangent bundle over the half-line as classical phase space leads to an incomplete quantum theory; the reflection which is a characteristic aspect of the 'hard wall' is not reproduced. Instead, we propose a different phase space that realises the necessary boundary condition as a topological feature and demonstrate that quantization yields a suitable quantum theory for the half-line model. The insights gained in the present special case improve our understanding of the relation between classical and quantum theory and illustrate how contact interactions may be incorporated.

Self, College Experiences, and Society: Rethinking the Theoretical Foundations of Student Development Theory

Science.gov (United States)

Winkle-Wagner, Rachelle

2012-01-01

This article examines the psychological theoretical foundations of college student development theory and the theoretical assumptions of this framework. A complimentary, sociological perspective and the theoretical assumptions of this approach are offered. The potential limitations of the overuse of each perspective are considered. The conclusion…

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

Science.gov (United States)

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.

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

International Nuclear Information System (INIS)

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)

Excitation and ionization of hydrogen and helium atoms by femtosecond laser pulses: theoretical approach by Coulomb-Volkov states

International Nuclear Information System (INIS)

Guichard, R.

2007-12-01

We present a theoretical approach using Coulomb-Volkov states that appears useful for the study of atomic multi-photonic processes induced by intense XUV femtosecond laser pulses. It predicts hydrogen ionization spectra when it is irradiated by laser pulses in perturbations conditions. Three ways have been investigated. Extension to strong fields when ℎω > I p : it requires to include the hydrogen ground state population, introducing it in standard Coulomb-Volkov amplitude leads to saturated multi-photonic ionization. Extension to multi-photonic transitions with ℎω p : new quantum paths are open by the possibility to excite the lower hydrogen bound states. Multiphoton excitation of these states is investigated using a Coulomb-Volkov approach. Extension to helium: two-photon double ionization study shows the influence of electronic correlations in both ground and final state. Huge quantity of information such as angular and energetic distributions as well as total cross sections is available. (author)

Thermalization and prethermalization in isolated quantum systems: a theoretical overview

Science.gov (United States)

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

2018-06-01

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

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

Czech Academy of Sciences Publication Activity Database

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

International workshop of the Confinement Database and Modelling Expert Group in collaboration with the Edge and Pedestal Physics Expert Group

International Nuclear Information System (INIS)

Cordey, J.; Kardaun, O.

2001-01-01

A Workshop of the Confinement Database and Modelling Expert Group (EG) was held on 2-6 April at the Plasma Physics Research Center of Lausanne (CRPP), Switzerland. Presentations were held on the present status of the plasma pedestal (temperature and energy) scalings from an empirical and theoretical perspective. An integrated approach to modelling tokamaks incorporating core transport, edge pedestal and SOL, together with a model for ELMs was presented by JCT. New experimental data on on global H-mode confinement were discussed and presentations on L-H threshold power were made

Sampling from a system-theoretic viewpoint

NARCIS (Netherlands)

Meinsma, Gjerrit; Mirkin, Leonid

2009-01-01

This paper studies a system-theoretic approach to the problem of reconstructing an analog signal from its samples. The idea, borrowed from earlier treatments in the control literature, is to address the problem as a hybrid model-matching problem in which performance is measured by system norms. The

Surface physics theoretical models and experimental methods

CERN Document Server

Mamonova, Marina V; Prudnikova, I A

2016-01-01

The demands of production, such as thin films in microelectronics, rely on consideration of factors influencing the interaction of dissimilar materials that make contact with their surfaces. Bond formation between surface layers of dissimilar condensed solids-termed adhesion-depends on the nature of the contacting bodies. Thus, it is necessary to determine the characteristics of adhesion interaction of different materials from both applied and fundamental perspectives of surface phenomena. Given the difficulty in obtaining reliable experimental values of the adhesion strength of coatings, the theoretical approach to determining adhesion characteristics becomes more important. Surface Physics: Theoretical Models and Experimental Methods presents straightforward and efficient approaches and methods developed by the authors that enable the calculation of surface and adhesion characteristics for a wide range of materials: metals, alloys, semiconductors, and complex compounds. The authors compare results from the ...

A Decision-Theoretic Basis for Choice Shifts in Groups

OpenAIRE

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...

A Dialectical Approach to Theoretical Integration in Developmental-Contextual Identity Research

Science.gov (United States)

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…

Group decision-making approach for flood vulnerability identification using the fuzzy VIKOR method

Science.gov (United States)

Lee, G.; Jun, K. S.; Chung, E.-S.

2015-04-01

This study proposes an improved group decision making (GDM) framework that combines the VIKOR method with data fuzzification to quantify the spatial flood vulnerability including multiple criteria. In general, GDM method is an effective tool for formulating a compromise solution that involves various decision makers since various stakeholders may have different perspectives on their flood risk/vulnerability management responses. The GDM approach is designed to achieve consensus building that reflects the viewpoints of each participant. The fuzzy VIKOR method was developed to solve multi-criteria decision making (MCDM) problems with conflicting and noncommensurable criteria. This comprising method can be used to obtain a nearly ideal solution according to all established criteria. This approach effectively can propose some compromising decisions by combining the GDM method and fuzzy VIKOR method. The spatial flood vulnerability of the southern Han River using the GDM approach combined with the fuzzy VIKOR method was compared with the spatial flood vulnerability using general MCDM methods, such as the fuzzy TOPSIS and classical GDM methods (i.e., Borda, Condorcet, and Copeland). As a result, the proposed fuzzy GDM approach can reduce the uncertainty in the data confidence and weight derivation techniques. Thus, the combination of the GDM approach with the fuzzy VIKOR method can provide robust prioritization because it actively reflects the opinions of various groups and considers uncertainty in the input data.

Gregory S. Ezra a festschrift from theoretical chemistry accounts

CERN Document Server

Keshavamurthy, Srihari

2015-01-01

In this Festschrift dedicated to the 60th birthday of Gregory S. Ezra, selected researchers in theoretical chemistry present research highlights on major developments in the field. Originally published in the journal Theoretical Chemistry Accounts, these outstanding contributions are now available in a hardcover print format, as well as a special electronic edition. This volume provides valuable content for all researchers in theoretical chemistry and will especially benefit those research groups and libraries with limited access to the journal.

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

International Nuclear Information System (INIS)

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

A Theoretical Framework for Ecological Interface Design

DEFF Research Database (Denmark)

Vicente, Kim J.; Rasmussen, Jens

1988-01-01

A theoretical framework for designing interfaces for complex systems is de-scribed. The framework, called ecological interface design (EID), suggests a set of principles for designing interfaces in a way that supports the funda-mental properties of human cognition. The basis of EID is the skills...... of the task require. The EID approach extends the concept of direct manipulation inter-faces by taking into account the added complications introduced by complex systems. In this paper, we describe the development of the framework, its theoretical foundations, and examples of its application to various work...

Nonlinear relativistic plasma resonance: Renormalization group approach

Energy Technology Data Exchange (ETDEWEB)

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.

Concluding theoretical remarks

International Nuclear Information System (INIS)

Ellis, J.

1986-01-01

My task in this talk is to review the happenings of this workshop from a theoretical perspective, and to emphasize lines for possible future research. My remarks are organized into a theoretical overview of the what, why, (mainly the hierarchy problem) how, (supersymmetry must be broken: softly or spontaneously, and if the latter, by means of a new U tilde(1) gauge group or through the chiral superfields) when (how heavy are supersymmetric partner particles in different types of theories) and where (can one find evidence for) supersymmetry. In the last part are discussed various ongoing and future searches for photinos γ tilde, gravitinos G tilde, the U vector boson, shiggses H tilde, squarks q tilde and sleptons l tilde, gluinos g tilde, winos W tilde and other gauginos, as well as hunts for indirect effects of supersymmetry, such as for example in baryon decay. Finally there is a little message of encouragement to our experimental colleagues, based on historical precedent. (orig.)

Comments on theoretical foundation of "EM Drive"

Science.gov (United States)

Wu, C.-W.

2018-03-01

The concept of EM Drive has attracted much attention and groups of work have been conducted to prove or verify it, of which the published experimental outcome is criticized in great details while the theoretical foundation has not been discussed. The present essay investigates on the theoretical derivations of the net thrust in the "EM drive" and reveals the self-contradiction arising at the very start, when the law of conservation of momentum was utilized and opposed simultaneously.

Competition between direct interaction and Kondo effect: Renormalization-group approach

International Nuclear Information System (INIS)

Allub, R.

1988-03-01

Via the Wilson renormalization-group approach, the effect of the competition between direct interaction (J L ) and Kondo coupling is studied, in the magnetic susceptibility of a model with two different magnetic impurities. For the ferromagnetic interaction (J L > 0) between the localized impurities, we find a magnetic ground state and a divergent susceptibility at low temperatures. For (J L < 0), two different Kondo temperatures and a non-magnetic ground state are distinguished. (author). 12 refs, 1 fig

The Effect of Group Therapy With Transactional Analysis Approach on Emotional Intelligence, Executive Functions and Drug Dependency.

Science.gov (United States)

Forghani, Masoomeh; Ghanbari Hashem Abadi, Bahram Ali

2016-06-01

The aim of the present study was to evaluate the effect of group psychotherapy with transactional analysis (TA) approach on emotional intelligence (EI), executive functions and substance dependency among drug-addicts at rehabilitation centers in Mashhad city, Iran, in 2013. In this quasi-experimental study with pretest, posttest, case- control stages, 30 patients were selected from a rehabilitation center and randomly divided into two groups. The case group received 12 sessions of group psychotherapy with transactional analysis approach. Then the effects of independent variable (group psychotherapy with TA approach) on EI, executive function and drug dependency were assessed. The Bar-on test was used for EI, Stroop test for measuring executive function and morphine test, meth-amphetamines and B2 test for evaluating drug dependency. Data were analyzed using multifactorial covariance analysis, Levenes' analysis, MANCOVA, t-student and Pearson correlation coefficient tests t with SPSS software. Our results showed that group psychotherapy with the TA approach was effective in improving EI, executive functions and decreasing drug dependency (P addicts and prevents addiction recurrence by improving the coping capabilities and some mental functions of the subjects. However, there are some limitations regarding this study including follow-up duration and sample size.

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

Science.gov (United States)

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.

Particle-beam driven inertial confinement fusion. A theoretical approach of the particle beam-matter interaction

International Nuclear Information System (INIS)

Duborgel, Bernard; Dufour, J.M.; Fedotoff, Michel; Gouard, Philippe.

1981-11-01

A major difficulty in the relativistic electron beam (REB) inertial confinement approach is the low REB-target coupling resulting from long electron range in the matter. The beam stagnation mechanism, induced in a thin target by macroscopic electric and magnetic fields, can appreciably enhance this coupling. The chapter 2 of the rapport contributes to the theoretical study of this effect. Models and numerical programs are described, which permit to establish the characteristics of this mechanism and evaluate the role of the various parameters. These models were used to interpret thin foils heating experiments performed on CHANTECLAIR generator at the Centre of Valduc. The orientation of particle research to the light ions beams (LIB) has to led to an intensive study of ions-matter interaction. DEPION model described in chapter 3 of the report provides an evaluation of energy deposition characteristics for any ion incident upon a target, taking into account their evolution during the plasma heating phase [fr

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

KAUST Repository

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.

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

KAUST Repository

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.

Free Boolean Topological Groups

Directory of Open Access Journals (Sweden)

Ol’ga Sipacheva

2015-11-01

Full Text Available Known and new results on free Boolean topological groups are collected. An account of the properties that these groups share with free or free Abelian topological groups and properties specific to free Boolean groups is given. Special emphasis is placed on the application of set-theoretic methods to the study of Boolean topological groups.

Intergovernmental approach of the new liberalism in the development of integration processes

Directory of Open Access Journals (Sweden)

O. P. Stadnyk

2013-12-01

Full Text Available Investigated intergovernmental theory approach to understanding the new liberalism integration processes. Determined the nature of the liberal intergovernmental approach that Andrew Moravchik developed within the new liberalism. Emphasized that the intergovernmental approach of the new liberalism theory considers national preferences in international relations as being primarily determined by domestic political processes. Liberal intergovernmental approach rejects the rhetoric of so­called national interests and instead focuses on interest groups that define a specific government policy regarding foreign partners. Specified on crucial economic lobbying pressure defined interest groups in the formation of national preferences. The features considering interest groups that determine foreign policy under the intergovernmental approach a theory of new liberalism. Singled out a number of critical approaches to the liberal intergovernmental approach given the nature explanation integration processes. Clarified the value of the intergovernmental approach within theories of political integration by taking into account the theoretical and conceptual foundations of his liberal variety ­ liberal intergovernmental approach as part of a new theory of liberalism, which involves the formation of national preferences in international relations through domestic contexts interaction of national interest groups and their lobbying pressure.

A Representation-Theoretic Approach to Reversible Computation with Applications

DEFF Research Database (Denmark)

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...

Heisenberg groups and noncommutative fluxes

International Nuclear Information System (INIS)

Freed, Daniel S.; Moore, Gregory W.; Segal, Graeme

2007-01-01

We develop a group-theoretical approach to the formulation of generalized abelian gauge theories, such as those appearing in string theory and M-theory. We explore several applications of this approach. First, we show that there is an uncertainty relation which obstructs simultaneous measurement of electric and magnetic flux when torsion fluxes are included. Next, we show how to define the Hilbert space of a self-dual field. The Hilbert space is Z 2 -graded and we show that, in general, self-dual theories (including the RR fields of string theory) have fermionic sectors. We indicate how rational conformal field theories associated to the two-dimensional Gaussian model generalize to (4k+2)-dimensional conformal field theories. When our ideas are applied to the RR fields of string theory we learn that it is impossible to measure the K-theory class of a RR field. Only the reduction modulo torsion can be measured

Hybrid quantum teleportation: A theoretical model

Energy Technology Data Exchange (ETDEWEB)

Takeda, Shuntaro; Mizuta, Takahiro; Fuwa, Maria; Yoshikawa, Jun-ichi; Yonezawa, Hidehiro; Furusawa, Akira [Department of Applied Physics, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

2014-12-04

Hybrid quantum teleportation – continuous-variable teleportation of qubits – is a promising approach for deterministically teleporting photonic qubits. We propose how to implement it with current technology. Our theoretical model shows that faithful qubit transfer can be achieved for this teleportation by choosing an optimal gain for the teleporter’s classical channel.

A game-theoretic approach to donor kidney sharing.

Science.gov (United States)

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.

THE NETWORKS IN TOURISM: A THEORETICAL APPROACH

Directory of Open Access Journals (Sweden)

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.

Theoretical elements for a historical approach to the family and its relations of violence during the transition between the XXth and XXIst centuries

Directory of Open Access Journals (Sweden)

Bárbara Yadira García Sánchez

2016-01-01

Full Text Available The objective of this article is to relect upon the history of the ield of contemporary family and its changes from the revolution of youth in 1960s until the irst decade of the XXIst century. This historical approach is linked to the study of relations of violence inside the family context. The implementation of certain theoretical and methodological concepts allowed us to establish a contrast between several time periods, starting from the present and going back to situations of the past, following the track of micro social conlicts expressed in violence toward parental igures, as well as in violence between siblings, all of which are analyzed as typologies of what has been called domestic violence. The theoretical relection is supported by some approaches of Pierre Bourdieu regarding the reproduction of symbolic violence, and more speciically, the strategies of its reproduction in the ield of family. We emphasize on the strategies of symbolic, ethicaland educational inversion. The data used to support this article is taken from the database of two research projects on school violence in Bogota between 2009 and 2015.

A GROUP INTERVENTION PROGRAMME FOR ADULT SURVIVORS OF CHILDHOOD SEXUAL ABUSE

Directory of Open Access Journals (Sweden)

Fouché, Ansie

2016-10-01

Full Text Available This study reports on the core components of the Survivor to Thriver strengths-based group intervention programme for women who experienced childhood sexual abuse. It advocates a balanced approach and draws on an eclectic mix of theories, and has been field tested with two groups of women. An exposition of the philosophical and theoretical underpinnings, a description of the context, the role of the expert companion, outcomes and activities of the programme, evaluation methods and standard of care is provided. Finally, critical reflections on the intervention are discussed as well as limitations and the way forward.

Design and feasibility testing of a novel group intervention for young women who binge drink in groups.

Science.gov (United States)

Irvine, Linda; Crombie, Iain K; Swanson, Vivien; Dimova, Elena D; Melson, Ambrose J; Fraser, Tracey M; Barbour, Rosaline; Rice, Peter M; Allan, Sheila

2018-01-01

Young women frequently drink alcohol in groups and binge drinking within these natural drinking groups is common. This study describes the design of a theoretically and empirically based group intervention to reduce binge drinking among young women. It also evaluates their engagement with the intervention and the acceptability of the study methods. Friendship groups of women aged 18-35 years, who had two or more episodes of binge drinking (>6 UK units on one occasion; 48g of alcohol) in the previous 30 days, were recruited from the community. A face-to-face group intervention, based on the Health Action Process Approach, was delivered over three sessions. Components of the intervention were woven around fun activities, such as making alcohol free cocktails. Women were followed up four months after the intervention was delivered. The target of 24 groups (comprising 97 women) was recruited. The common pattern of drinking was infrequent, heavy drinking (mean consumption on the heaviest drinking day was UK 18.1 units). Process evaluation revealed that the intervention was delivered with high fidelity and acceptability of the study methods was high. The women engaged positively with intervention components and made group decisions about cutting down. Twenty two groups set goals to reduce their drinking, and these were translated into action plans. Retention of individuals at follow up was 87%. This study successfully recruited groups of young women whose patterns of drinking place them at high risk of acute harm. This novel approach to delivering an alcohol intervention has potential to reduce binge drinking among young women. The high levels of engagement with key steps in the behavior change process suggests that the group intervention should be tested in a full randomised controlled trial.

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

International Nuclear Information System (INIS)

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

Something new: a new approach to correcting theoretical emitted intensities for absorption effects

International Nuclear Information System (INIS)

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

Definable Group Extensions and o-Minimal Group Cohomology via Spectral Sequences

OpenAIRE

BARRIGA, ELIANA

2013-01-01

We provide the theoretical foundation for the Lyndon-Hochschild-Serre spectral sequence as a tool to study the group cohomology and with this the group extensions in the category of definable groups. We also present various results on definable modules and actions, definable extensions and group cohomology of definable groups. These have applications to the study of non-definably compact groups definable in o-minimal theories (see [1]). Se presenta el fundamento teórico para las sucesiones...

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

Science.gov (United States)

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.

An information-theoretic approach to the modeling and analysis of whole-genome bisulfite sequencing data.

Science.gov (United States)

Jenkinson, Garrett; Abante, Jordi; Feinberg, Andrew P; Goutsias, John

2018-03-07

DNA methylation is a stable form of epigenetic memory used by cells to control gene expression. Whole genome bisulfite sequencing (WGBS) has emerged as a gold-standard experimental technique for studying DNA methylation by producing high resolution genome-wide methylation profiles. Statistical modeling and analysis is employed to computationally extract and quantify information from these profiles in an effort to identify regions of the genome that demonstrate crucial or aberrant epigenetic behavior. However, the performance of most currently available methods for methylation analysis is hampered by their inability to directly account for statistical dependencies between neighboring methylation sites, thus ignoring significant information available in WGBS reads. We present a powerful information-theoretic approach for genome-wide modeling and analysis of WGBS data based on the 1D Ising model of statistical physics. This approach takes into account correlations in methylation by utilizing a joint probability model that encapsulates all information available in WGBS methylation reads and produces accurate results even when applied on single WGBS samples with low coverage. Using the Shannon entropy, our approach provides a rigorous quantification of methylation stochasticity in individual WGBS samples genome-wide. Furthermore, it utilizes the Jensen-Shannon distance to evaluate differences in methylation distributions between a test and a reference sample. Differential performance assessment using simulated and real human lung normal/cancer data demonstrate a clear superiority of our approach over DSS, a recently proposed method for WGBS data analysis. Critically, these results demonstrate that marginal methods become statistically invalid when correlations are present in the data. This contribution demonstrates clear benefits and the necessity of modeling joint probability distributions of methylation using the 1D Ising model of statistical physics and of

Harmless survey of the theoretical situation in the high temperature superconductivity

International Nuclear Information System (INIS)

Gorkov, L.P.

1989-01-01

The theoretical understanding of the new superconductors progresses slowly despite the large amount of publications. The intention of this paper is to show that partially this is so because a number of key problems remain unresolved experimentally. Meanwhile, some of the recent findings point out in the direction which, if correct, may drastically change theoretical views. Before the authors discuss these new experimental results, a brief overview of the different theoretical approaches is given below

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

Energy Technology Data Exchange (ETDEWEB)

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

Theoretical study of γ-hexachlorocyclohexane and β-hexachlorocyclohexane isomers interaction with surface groups of activated carbon model.

Science.gov (United States)

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.

A renormalization group study of persistent current in a quasiperiodic ring

Energy Technology Data Exchange (ETDEWEB)

Dutta, Paramita [Theoretical Condensed Matter Physics Division, Saha Institute of Nuclear Physics, Sector-I, Block-AF, Bidhannagar, Kolkata-700 064 (India); Maiti, Santanu K., E-mail: santanu.maiti@isical.ac.in [Physics and Applied Mathematics Unit, Indian Statistical Institute, 203 Barrackpore Trunk Road, Kolkata-700 108 (India); Karmakar, S.N. [Theoretical Condensed Matter Physics Division, Saha Institute of Nuclear Physics, Sector-I, Block-AF, Bidhannagar, Kolkata-700 064 (India)

2014-04-01

We propose a real-space renormalization group approach for evaluating persistent current in a multi-channel quasiperiodic Fibonacci tight-binding ring based on a Green's function formalism. Unlike the traditional methods, the present scheme provides a powerful tool for the theoretical description of persistent current with a very high degree of accuracy in large periodic and quasiperiodic rings, even in the micron scale range, which emphasizes the merit of this work.

Quantum renormalization group approach to geometric phases in spin chains

International Nuclear Information System (INIS)

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

Bayesian analysis of systems with random chemical composition: renormalization-group approach to Dirichlet distributions and the statistical theory of dilution.

Science.gov (United States)

Vlad, Marcel Ovidiu; Tsuchiya, Masa; Oefner, Peter; Ross, John

2002-01-01

We investigate the statistical properties of systems with random chemical composition and try to obtain a theoretical derivation of the self-similar Dirichlet distribution, which is used empirically in molecular biology, environmental chemistry, and geochemistry. We consider a system made up of many chemical species and assume that the statistical distribution of the abundance of each chemical species in the system is the result of a succession of a variable number of random dilution events, which can be described by using the renormalization-group theory. A Bayesian approach is used for evaluating the probability density of the chemical composition of the system in terms of the probability densities of the abundances of the different chemical species. We show that for large cascades of dilution events, the probability density of the composition vector of the system is given by a self-similar probability density of the Dirichlet type. We also give an alternative formal derivation for the Dirichlet law based on the maximum entropy approach, by assuming that the average values of the chemical potentials of different species, expressed in terms of molar fractions, are constant. Although the maximum entropy approach leads formally to the Dirichlet distribution, it does not clarify the physical origin of the Dirichlet statistics and has serious limitations. The random theory of dilution provides a physical picture for the emergence of Dirichlet statistics and makes it possible to investigate its validity range. We discuss the implications of our theory in molecular biology, geochemistry, and environmental science.

Basis of integrated approach to sports and recreational activities of students of special medical groups

Directory of Open Access Journals (Sweden)

L.V. Zaharova

2014-02-01

Full Text Available Purpose : to prove the superiority of techniques integrated approach to sports and recreational activities of students of special medical groups in the educational institution. Material / methods : the annual pedagogical experiment conducted on three groups that have been formed based on the results of preliminary studies based on diagnosis. Learning process based on the principle of improving training. Results : the advantages of an integrated approach to sports and recreational activities of students with disorders of the musculoskeletal system. Recommended approaches to increase physical and functional training. Also - the formation of a stable demand of motor activity, leading healthy lifestyles, in the acquisition of social status in the educational activity. Conclusions : the integrated approach will meet the educational needs of students to form a cultural competence of the individual in the preservation and conservation of health, ability to adapt and successfully implement their professional activities.

Canonical group quantization and boundary conditions

Energy Technology Data Exchange (ETDEWEB)

Jung, Florian

2012-07-16

In the present thesis, we study quantization of classical systems with non-trivial phase spaces using the group-theoretical quantization technique proposed by Isham. Our main goal is a better understanding of global and topological aspects of quantum theory. In practice, the group-theoretical approach enables direct quantization of systems subject to constraints and boundary conditions in a natural and physically transparent manner -- cases for which the canonical quantization method of Dirac fails. First, we provide a clarification of the quantization formalism. In contrast to prior treatments, we introduce a sharp distinction between the two group structures that are involved and explain their physical meaning. The benefit is a consistent and conceptually much clearer construction of the Canonical Group. In particular, we shed light upon the 'pathological' case for which the Canonical Group must be defined via a central Lie algebra extension and emphasise the role of the central extension in general. In addition, we study direct quantization of a particle restricted to a half-line with 'hard wall' boundary condition. Despite the apparent simplicity of this example, we show that a naive quantization attempt based on the cotangent bundle over the half-line as classical phase space leads to an incomplete quantum theory; the reflection which is a characteristic aspect of the 'hard wall' is not reproduced. Instead, we propose a different phase space that realises the necessary boundary condition as a topological feature and demonstrate that quantization yields a suitable quantum theory for the half-line model. The insights gained in the present special case improve our understanding of the relation between classical and quantum theory and illustrate how contact interactions may be incorporated.

Game-theoretic approaches to optimal risk sharing

NARCIS (Netherlands)

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

Research in theoretical nuclear physics. Final report, April 1, 1993 - March 31, 1996

International Nuclear Information System (INIS)

Udagawa, Takeshi

1997-08-01

This report describes the accomplishments in basic research in nuclear physics carried out by the theoretical nuclear physics group in the Department of Physics at the University of Texas at Austin, during the period of April 1, 1993 to March 31, 1996. The work done covers three separate areas, low energy nuclear reactions, intermediate energy physics, and nuclear structure studies. Although the various subjects are spread among different areas, they are all based on two techniques that they have developed in previous years. These techniques are: (a) a powerful method for continuum-random-phase-approximation (CRPA) calculations of the nuclear response; and, (b) the direct reaction approach to complete and incomplete fusion reactions, which enables them to describe on a single footing all the different types of nuclear reactions, i.e., complete fusion, incomplete fusion and direct reactions, in a systematic way based on a single theoretical framework. In this report, the authors first summarize their achievements in these three areas, and then present final remarks

Analyses of the structure of group correlations in Korean financial markets

Science.gov (United States)

Ko, Jeung Su; Lim, Gyuchang; Kim, Kyungsik

2012-12-01

In this paper, we construct and analyze the structure of cross-correlations in two Korean stock markets, the Korea Composite Stock Price Index (KOSPI) and the Korea Securities Dealers Automated Quotation (KOSDAQ). We investigate a remarkable agreement between the theoretical prediction and the empirical data concerning the density of eigenvalues in the KOSPI and the KOSDAQ. We estimate daily cross-correlations with respect to price fluctuations of 629 KOSPI and 650 KOSDAQ stock entities for the period from 2006 to 2010. The research for the structure of group correlations undress the market-wide effect by using the Markowitz multi-factor model and network-based approach. We find stock entities that involve the same business sectors and verify the structure of group correlations by applying a network-based approach. In particular, the KOSPI has a dense correlation besides overall group correlations for stock entities, whereas both correlations are less for the KOSDAQ than for the KOSPI.